COMPLICATIONS IN HAND SURGERY

INTRODUCTION

Normally, the hand is a transparent interface, performing voluntary tasks without bringing attention to itself. Following hand injury, recovery of anything less than this level of performance is a complication. By this measure, complications of hand injuries are very common, and the primary goal of the treatment of hand trauma is simply that of avoiding complications.

Complications in this chapter are grouped according to whether they are considered to be complications of missed diagnoses, complications of treatment, or complications of injuries. Although there is overlap in these categories, they form a framework for the treating physician to organize a personal approach to reduce the risk of complications in hand surgery.

MISSED DIAGNOSES

Missed Hand Injuries. The best insurance against missed diagnosis of hand injuries is an adequate history and physical examination.

History. Severe upper extremity injuries are frequently dramatic and attended by emotional factors. Because of this, it is usually best to obtain a history in a deliberate, orderly way. If possible, after hearing the story, the examiner should physically demonstrate the scenario of injury back to the patient to confirm the examiner's understanding of the details, including the position of the extremity at the time of injury. If an injury involves machinery, it should be described well enough to be visualized, in simple mechanical terms: was the mechanism sharp or dull? Did the mechanism involve rotating blades, belts, or chains? Was there exposure to heat, cold, or chemicals? Much of the nature of damage and extent of injury can be predicted before the examination. For example: Did the patient land on their palm with their wrist extended or on the dorsum of their wrist? Was the patient able to pull their hand out, or was it trapped, requiring extrication? Was the bleeding pulsatile? Even in what seems to be an obvious situation, clarification is important, and one should not assume that all problems with the hand developed as a consequence of a single reported injury: Did the pain start immediately after the event, or later? Did the numbness begin at the time of injury or later? Has the hand been injured previously? Recently? A long time ago? Before the injury, were there any problem with numbness, weakness or pain? Shoulder problems? Night time hand numbness? Attention to such details from the onset can avoid misguided treatment and false expectations. Additionally, hand injuries are a common starting point for personal injury litigation, and clear initial documentation of these points will prevent needless later aggravation at the hands of lawyers.

Examination. A working knowledge of anatomy usually allows much of the examination for an acute injury to be performed without touching the obvious site of injury. Sensory, motor and vascular examination distal to the injury can provide clues as to the status of more proximal wounds. This gentle approach is clearly preferable to attempting to define the injury by probing or instrumenting a wound in the emergency room.

Rapid survey of the hand. A focused, informative survey of the injured hand can be performed in about a minute. It is best to proceed with examination of the injured hand using a systems check list technique:

Objective findings

Subjective findings Tips for examining the hand of an unconscious patient. Objective examination is obviously limited when with the patient is not fully cooperative, but much can still be assessed in the absence of subjective findings using these four categories of assessment:

Vascular: Color of the skin and nail beds compared to the opposite side can indicate arterial (pale) or venous (dark or purple) insufficiency. Allen's test can be performed without patient participation by gently squeezing the palm while occluding radial and ulnar arteries at the wrist, then releasing one artery to assess patency of the two main arteries as well as the palmar arch. Digital Allen's test is performed in similar fashion, using the examiner's fingertips to exsanguinate a finger from distal to proximal, and then releasing one or the other side at the base of the finger (digitalallen.htm). Forearm compartment pressures can be measured with commercial kits or with materials available in any emergency room.

Muscle and Tendon: Posture of the fingers can indicate specific tendon injuries. Even if the patient is unconscious or under anesthesia, if the tendons and phalanges are intact, the fingers should assume a cascade position of progressively more flexion of both proximal and distal interphalangeal joints proceeding from the index to the small finger (survey.htm, cuttend.htm). Tenodesis motion of the fingers can be used to check relative finger posture during passive wrist flexion and extension (tenodesis2.htm, tenodesis4.htm). Squeezing the mid forearm will tighten the finger flexor tendons and mimic their active action.

Bone and Joint: Rotation of the fingers may be suspected if the tips overlap, but if the fingertips are not adjacent during flexion, it is normal for them all to converge toward a common target - the distal pole of the scaphoid, where the flexor carpi radialis tendon intersects the wrist flexion crease (point2.htm, 1432000s.htm). Contour abnormalities at joints or along long bones may indicate fractures or dislocations. Common contour changes due to displaced fractures include those due to distal radius fractures (1493502sx.htm), metacarpal neck fractures, and proximal phalanx fractures. Metacarpophalangeal or proximal interphalangeal joint dislocations alter flexor / extensor tendon tension balance and may present as unusual posture or positioning of joints distal to the injury (1437308x.htm). Bruising at a site away from an area of impact, such as dorsal wrist bruising after a fall on the outstretched palm, strongly suggests an underlying skeletal injury even with normal x-rays. Passive range of motion of the elbow, wrist and fingers can be used to assess crepitation (joint surface injury), resistance (swelling, subluxation, dislocation) and instability (ligament injury).

Nerve: Because the digital nerves are superficial to the digital arteries, an abnormal digital Allen test (digitalallen.htm) in the context of any palmar finger laceration strongly suggests an associated digital nerve injury, because the zone of external injury must pass through the nerve before reaching the artery . Tactile adherence is assessed by sliding an object with a smooth surface across the palmar skin. Compared to normal skin, a smooth surface such as a glass slide or the barrel of a shiny smooth plastic pen will slide with much less resistance ("adherence") over skin affected by nerve injury because recently denervated skin does not sweat. Normally, microscopic sweat droplets on the palmar skin confer some palpable resistance to this motion. The wrinkle test makes use of the finding that  recently denervated skin does not wrinkle with prolonged water contact. In this this test, fingers are immersed in water (not saline or other salt solution) for five minutes, the inspected for wrinkling, which indicates denervation if absent (1491801s.htm). The mechanism of this test is unknown.

Missed problems elsewhere. A dramatic hand injury can divert the attention of both the surgeon and the patient from a standard trauma systems evaluation. Complications from missed injuries are most likely when a patient has sustained a traumatic amputation in a blunt trauma scenario, such as a traffic accident or a fall. Life threatening central nervous system or thoracoabdominal injuries may be missed, as well as proximal skeletal and brachial plexus injuries. A common occult medical condition accompanying hand injury is substance abuse: in one report, nearly half of patients requiring emergency room treatment for hand trauma tested positive for alcohol or other substance abuse (AA).

COMPLICATIONS OF TREATMENT

Common complications of the treatment of hand injuries

The most common complication of any hand injury is stiffness, due to the collaborative effects of inflammation, swelling and immobility. Attempts at prevention of stiffness are much more effective and worthwhile than later attempts to correct established stiffness. This and other complications are less likely when the treatment follows priority based guidelines.

Priorities: Management priorities are the same for severe and minor injuries: establish the extent of injury; remove the bad; reconstruct the good; involve the patient and tailor the surgery to the patient (CO). Severe upper extremity injuries with soft tissue loss have shorter hospitalization and more rapid recovery with primary reconstruction, even if this requires primary microvascular free flap surgery (DC). One conceptual approach to organizing the initial management of severe head injuries is to break down priorities as they relate to either healing or function:

Healing priorities: circulation, skeleton, closure: Inadequate blood supply is the single most likely explanation for complications of delayed healing, fibrosis and infection. Adequate blood supply is achieved by aggressive debridement, revascularization, and use of vascularized flaps. Edema represents inadequate lymphatic circulation, and has the same ultimate effects as inadequate blood supply. Edema is best treated with elevation and active range of motion, when permitted. Optimum bone and joint reconstruction goals are prompt, anatomic reduction of injury and stable skeletal fixation with the least amount of additional soft tissue disruption. Wound closure with mobile, well vascularized soft tissue cover should be achieved as quickly as possible. In the hand, stiffness, difficulty with use and ultimate disability is directly related to the length of time required for wound healing.

Function priorities: nerve, joint, muscle: Nerve injuries should be approached aggressively, as there is never a better time to evaluate and to perform repairs, and the only satisfactory time to repair partial nerve lacerations is in the acute setting (prtnerve2.htm, foreign.htm). Passive range of motion has two components: The first is preservation of the gliding function of the surfaces of the joints and tendons. This is achieved by early protected motion: all moving parts in which are safe to move are moved frequently, against no resistance and at the earliest opportunity. The second is maintenance of physiological length of capsuloligamentous and muscular tissues. This is achieved by splinting the hand in between exercises in the "protective position": interphalangeal joint extension, metacarpophalangeal joint flexion, and preservation of the thumb-index web space span (safepose.htm). Active range of motion additionally reduces edema, builds strength, promotes bone healing, prevents dysfunctional patterns of disuse, and probably reduces the incidence of complex regional pain syndrome.

Complications of bandaging

Tight dressings: Finger dressings made from tubular gauze may produce ischemic pressure complications.  Technical errors in application predisposing to tubular gauze pressure complications include excessive longitudinal traction during application, using more than a 90 degree twist during application, and rolled proximal dressing edges (AX). Even minimally tight elastic dressings applied as part of a circumferential bandage may lead to progressive swelling, aggravating all of the ill effects of swelling on the injured hand, as described above.  Swelling may hinder assessment and may delay surgery until reduced by elevation and change to a noncompressive dressing. Complications of elastic dressings are less when applied with care, and when applied over a bulky soft non circumferential bandage. The technical trick is to place a multiple linear circumferential gauze bandage as the deepest portion of the bandage, then split it longitudinally before completing the bandage.  This ensures that at least the deepest layer of bandage cannot provide circumferential pressure. Tight casts may result in local pressure sores, discomfort, and in the worst scenario, vascular compromise and compartment syndrome. The situation at greatest risk is circumferential casts applied after closed reduction of an elbow or forearm fracture on the day of injury.  In this situation, the risk may be reduced by primarily splitting the cast immediately after application.

Inadequate positioning: Splints and other supportive dressings maintain a posture which may be helpful or detrimental.  Often, splints fabricated in the emergency room for comfort maintain joints in positions which promote  stiffness.  Even splints intended to maintain the generic "protective position" may actually do just the opposite, a problem which may only be confirmed by x-ray (safepose2.htm).

Complications of wound care: The goal of wound care is to maintain an environment which discourages excessive bacterial growth and encourages normal healing.  Excessive bacterial growth occurs on moist undisturbed services, and is a common problem in the interdigital web spaces of the immobilized hand, and beneath occlusive bandages. Eventually, unchecked surface growth produces such high concentrations of organisms that the skin is invaded directly, producing maceration dermatitis.  This may progress to cellulitis, but in the early stages can be stopped by increasing frequency addressing changes, and when possible, allowing be affected skin to dry. Allergic contact dermatitis   may develop over the course of treatment using topical antibiotics or skin preparation formulas such as Mastisol (dermatitis.htm). This can produce a confusing picture, for inflammation associated with the reaction may be confused with infection. The early hallmarks of contact dermatitis are itching and blistering accompanying the reaction.

Complications of hand procedures

Tourniquet palsy after surgery occurs in an average of one in 5000 cases, more commonly associated with microsurgical than other procedures (AY). All nerves are usually affected to some degree, the radial nerve usually worst affected. Tourniquet palsy is more likely in patients with coagulation disorders, pre-existing neuropathy, thin malnourished patients, those with systemic lupus erythematosus (AY) and in instances of unintentionally high tourniquet pressures due to gauge failure (BM).

Toxic shock syndrome is a rare complication, but has been reported after elective reconstructive hand surgery (BI).

Needle stick / vascular cannulation injuries

Radial artery catheterization may result in acute hand ischemia if there is inadequate perfusion through the ulnar artery (BS). This problem is more likely when ulnar artery perfusion is not confirmed by Allen's test before catheterization, when relatively large diameter cannulas (18 gauge versus 20 gauge) are used (BV), during prolonged periods of cannulation, and in hypercoagulable states (BS). In the presence of ulnar artery occlusion, even a single radial artery needle stick for arterial blood gas determination can precipitate acute hand ischemia (vascular.htm). Although uncommon, ischemia resulting in finger amputation has been reported after arterial monitoring in infants (CL).

Cutaneous nerve injury. The cephalic vein is frequently cannulated for intravenous access.  It is closely related to the antebrachial cutaneous nerve in the proximal forearm and branches of the superficial radial nerve in the distal forearm.  Although uncommon, needle stick injuries of either of these nerves can occur (BJ) and lead to prolonged morbidity. Patients report feeling a strong electrical paresthesia at the time of injury, which should be taken as a sign of possible injury. Numbness or tingling lasting more than a day may represent partial nerve injury, and should lead to consideration of early exploration. Treatment options for chronic cases are the same as for any cutaneous neuroma, although more likely to be compounded by the effects of litigation.

Suppurative thrombophlebitis (see below).

Extravasation injuries (DY, DZ, EA, EB, EC, ED, EE) of the hand are common, because of the common use of the hand for intravenous access. Local tissue necrosis has been reported following subcutaneous extravasation of chemotherapy, osmotically active substances, and tissue toxic preparations such as injectable phenytoin. These injuries often have delayed presentation, delayed healing, and prolonged morbidity, requiring reconstructive surgery if treated late. Major limb growth disturbances may occur following extravasation or thrombosis in the neonatal period. Although not well described in the literature, tense hematomas associated with intravenous access of the wrist or dorsal hand may also result in tissue loss (hematoma.htm). Extravasation injuries have the best potential outcome when recognized and treated early.  Unfortunately, delayed presentation is still common because of the typically slow development of visible signs of injury.  Treatment recommendations have varied over the years, but early treatment with soft tissue infiltration/irrigation has the most consistent history of effectiveness. Local injection with hyaluronidase is helpful, but this drug is no longer available for use. Prevention appears to be the best approach, by avoiding of the dorsal hand, anterior wrist, and antecubital fossa, as these locations are most prone to complications from extravasation.

Prior axillary lymphadenectomy: Although it is common practice to instruct patients who have undergone mastectomy and axillary dissection to avoid manipulation or instrumentation of the hand, there is not a documented increased risk of complications in this context (DP). Hand surgery on the side of previous axillary dissection is probably safe.

Complications of anesthesia

Epinephrine in digital block: Although it is traditional teaching that epinephrine used in digital nerve blocks may result in digital gangrene, there are no actual reported cases of finger gangrene resulting specifically from the use of epinephrine with lidocaine for digital block, and its safe use has been reported (AN).

Postoperative ulnar nerve palsy due to ulnar neuropathy at the level of the elbow is a recognized but poorly understood complication of surgery involving general anesthesia (AR). The exact mechanism of this process remains unknown.  Preventative measures, including protective positioning on the operative table, use of elbow pads, avoidance of arm abduction, pronation and elbow flexion may reduce that has not been shown to prevent the development of this problem.  Final outcome is unpredictable, and both conservative and operative treatments have yielded mixed results.

Brachial plexus block anesthesia has been reported to have an incidence of postoperative dysesthesias ranging from less than two per cent (DT, DU) to as high as a twelve per cent (AT, DQ). Although rare, perineural fibrosis (DS) and permanent neurologic injury (AU) following axillary block anesthesia has also been reported. Complex regional pain syndrome has been reported to be both more common and less common after axillary brachial plexus block.

COMPLICATIONS OF INJURY

General complications of hand injury

Severe hand injuries are most often due to crush or rotating blade mechanism, and are best treated by a hand surgery specialist (CO).  Such injuries usually involve all organ systems of the hand and are always associated with complications.  Treatment principles and initial management which may be adequate for lesser injuries may be inadequate in the management of a mangled hand (DI). Intervention by a specialist reduces the duration and extent of disability as well as reducing the overall care requirements and cost for care in severe extremity trauma.

Scar contracture: Contractures due to skin scarring are more likely to be a problem if scars extend longitudinally across the flexor surface of a joint. Scar contractures in severe cases may develop over the first few weeks after injury, but in many cases progress over the course of months.  In the growing child, scar contractures may lead to progressive growth disturbances. Stiffness and contractures due to mechanical changes in joints and tendons, as discussed above, may develop independently.

Cosmetic deformity: The immature scar may be hypertrophic: thick, red, and raised.  These changes usually resolve gradually over the course of a year, although the process may take longer in young children.  Permanent visible deformity from hyperpigmentation, thin stretched scars over extensor surfaces, and tight scar bands across flexor surfaces may all be troublesome. Fingernail deformities are common after lacerations and crush injuries in the area of the nailbed. The most common problems are split nail from nailbed injury and hook nail deformity from loss of the tuft of the distal phalanx in a fingertip amputation. Such problems are sometimes unavoidable, but the best prevention is meticulous anatomic repair of nailbed lacerations.  Once established, fingernail deformities may be difficult or impossible to correct.

Complex regional pain syndrome: (rsd.htm, tipsrsd.htm) Complex regional pain syndrome, previously known as reflex sympathetic dystrophy, algodystrophy, sympathetic maintained pain, Sudeck's atrophy and other names may develop after any hand injury, particularly when associated with nerve injury or irritation. This problem may occur spontaneously, after major or minor injury. It variably involves spontaneous burning pain, hyperalgesia, swelling, vasomotor disturbances, disuse, and exacerbations by movement. Although there may be spontaneous resolution, the majority of patients develop some degree of chronic symptoms such as pain, stiffness, and difficulty with normal use of the hand despite all available treatment (EF). Best results of treatment require early recognition, aggressive medical therapy, and elimination of triggering phenomena. Medical therapy may involve sympathetic nerve blocks, gabapentin or other medications, and biofeedback. Triggers known to aggravate the condition include peripheral nerve irritation from neuroma or compressive neuropathy, aggressive passive range of motion in therapy, and dynamic hand splinting. The effects of complex regional pain syndrome may be far more disabling than the initial injury.

Dysfunctional use: Patients may develop maladaptive patterns of use after injury, ranging from awkward positioning to complete disuse of the hand. This is often due to unconscious reflex protective mechanisms, and may be difficult to correct. Extensor habitus refers to the tendency for the injured index finger or small finger to be held in extension. This unconscious posturing is powered by the independent extensor of the finger, and is best treated by early recognition and buddy taping. Alien hand syndrome refers to a complete disuse of the hand accompanied by a perception by the patient that the hand is "not theirs". Such problems may also be factitious, but labeling them as such does not improve the overall outcome.

Compartment syndrome of the hand may develop after crush injury, reperfusion following fracture related ischemia, intravenous injections, crush or blast injury (BB), bleeding following fracture, arterial cannulation or regional surgery, or due to prolonged pressure on the hand or arm. The forearm is the most common site for compartment syndrome in the upper extremity. Compartment syndrome of the upper extremity is more likely to develop in patients who are obtunded. Seriously ill children who receive multiple venous and arterial injections are also at particular risk. Treatment requires prompt recognition and decompression of intrinsic muscle compartments as well as carpal tunnel released in selected cases (AS). The late consequence of compartment syndrome of the upper extremity is Volkmann's contracture (BB, CS) which involves both muscle contracture and local ischemic neuropathy. Ischemic muscle contractures respond poorly to nonoperative measures such as splinting, and requires an aggressive surgical approach using muscle slides, tendon lengthening and tendon transfers similar to those used in the treatment of upper extremity spasticity. Neurolysis is indicated for persistent nerve symptoms, but outcome is unpredictable.

Complications of specific injuries

Complications of complex wounds Complex wounds are wounds which require additional procedures, such as radical debridement, to achieve wound closure.

Complications of missed complex wounds

Severe contamination is a common theme in missed complex wounds of the hand because the hand is so often physically exposed to contaminated mechanisms of injury.

Bite injuries

Human bite injuries of the hand most often take the form of clenched fist bite injuries, sustained when the hand strikes the mouth of another person in an altercation. The most common constellation of injuries is a skin laceration at the metacarpal head level, accompanied by extensor tendon injury and metacarpal head injury.  The pitfall in managing this injury is the fact that the injury is usually sustained when the hand is in a clenched fist position, but the patient frequently does not present until the hand is swollen and the metacarpophalangeal joint is held in extension.  This change of position places the soft tissue and bone injuries at an offset, giving the appearance that the injury is more superficial than it is (1071401S.htm, boxer4.htm). Treatment requires a high level of suspicion and aggressive debridement and intravenous antibiotics appropriate for a bite injury.

Animal bite injuries of the hand are most often from dog and cat bites. They can lead to prolonged morbidity, particularly when there is a delay between injury and initial treatment (CR). Dog bites are associated with soft tissue crush injury and fractures. Cat bites are particularly dangerous in hand because the needle like teeth of the cat can easily penetrate into joint spaces, tendon sheaths and other deep compartments of the hand through a relatively innocuous appearing skin wound.

Insect bites of the hand such as brown recluse spider bites may cause painful, slow healing wounds with chronic functional deficits. The initial bite injury may be painless. When surgical excision is indicated, results appear to be better when surgery is delayed until after the acute inflammatory process has subsided (EF).

Rattlesnake bite injuries of the upper extremity have serious complications and at least one third of cases, including local soft tissue necrosis (most common complication), coagulopathy, stiffness, loss of sensibility, and Volkmann's contracture (BT). Antivenin and steroids reduce the degree of swelling and hemorrhage, but do not affect or prevent tissue necrosis (snakebite.htm), which may require operative treatment.

Chemical Burns

Industrial acid burns of the hand occur when the inexperienced or careless worker splashes even small amounts of acid on their fingers or hand.  This type of injury can go undetected on initial evaluation unless a careful history is obtained because visible signs of injury are often delayed (hfl.htm). Hydrochloric and hydrofluoric acids are used in industrial processing, and may cause severe burns which are not manifest for a day after exposure. Early recognition and treatment with topical, intravenous or intraarterial calcium gluconate reduce pain and extent of tissue loss.

White phosphorus burns are sustained in the handling of military munitions, fireworks, and other industrial and agricultural products. Deep progressive burns and systemic effects of multiple organ system failure may result. Although copper sulfate has been recommended as a specific antidote, the most safe and effective treatment is copious water irrigation (EH). Again, immediate recognition and treatment of the nature of injury is essential to reduce long term complications.

Injection injuries

High pressure injection injuries of paint, sand, lubricating fluid and other materials are uncommon, but important because they are also on the list of injuries missed in the accident ward. Typically, the patient has briefly placed their hand or fingertip over a pressure spray nozzle, sustaining an injection of material into the soft tissues. Under pressure, this material tracks up tissue planes next to flexor tendons, nerves, arteries and through the named bursae and compartments of the hand and arm. Debris may be driven from the fingertip to the chest wall. The examiner may be misled by a small visible wound and (depending on the material injected) relatively few physical findings, and the patient may be discharged only to return within 24 hours because of worsening symptoms. X-rays may show soft tissue air, particulate debris, or pigment in certain types of paint. Treatment is emergency radical debridement (CN). The pressure injected material tends to track through the loose areolar tissue along longitudinal structures, and only careful debridement may allow preservation of all vital structures (1491601x.htm). In contrast, late surgical treatment may require en bloc tumor like excision of contaminated zones or amputation. Late results are worst when the injected material is either a petroleum based solvent or particulate (sandblasting) material, when the tendon sheath is involved, and when there is wide proximal spread of the injected material (DH). The injected material is not sterile, and prophylactic antibiotic treatment is indicated. Pressure injection injuries presenting with poor perfusion should be treated with primary amputation (DH). Injection of pressurized aerosol flurocarbon liquids such as used in refrigerants may additionally result in deep frostbite injury.

Intentional injection injuries of household cleaners, solvents, mercury or illicit drugs may be difficult to sort out because of either delusional or drug seeking nature of the patient. X-rays may show particulate or metallic debris or evidence of gas forming infection (ivdagas.htm).

Factitious or intentional wounds of the hand are uncommon, but very difficult to treat successfully because of recurrence. Swelling, ulceration, and recurrent wound breakdown are common themes. Such wounds are most typical on the dorsum of the nondominant hand. Narcotic seeking behavior may be part of the overall picture. The most important aspect of treatment is recognition, so that unnecessary, unsuccessful, or mutilating procedures may be avoided.  Although the problem is psychiatric, psychiatric intervention may or may not be helpful, and confrontation is generally ineffective intervention.  Such patients may jump from doctor to doctor in a community, and it is wise to notify local colleagues when such a patient is identified.

Complications of obvious complex wounds: Complex wounds are, by definition, prone to complications even with ideal management.  Common complex injuries of the hand have predictable types of complications, which are listed below.
Traumatic amputations of the hand most often involve the fingers. The associated nerve injury always forms a neuroma, and the treating surgeon should trim the digital nerve ends away from the distal wound to lessen the chance of disabling scar tenderness. Dysesthesia is common and all patients should be provided with an early desensitization program that they can do at home. Complex regional pain syndrome may be triggered and then maintained by tender finger amputation stumps (tipsrsd.htm) and early on may be difficult to distinguish from swelling, stiffness, tenderness and avoidance always associated with the injury.  Cold sensitivity or intolerance is a problem for the majority of patients, but usually improves after the first year. When there is loss of more than the distal third of the distal phalanx, a hook nail deformity will result, with the fingernail curving toward the palm, covering the distal fingertip. This and other variations of retained nail remnant may be avoided by careful total excision of the entire germinal matrix of the time of amputation closure. Fingertip amputations are no less problematic than more proximal amputations, particularly when the critical contact areas used in pinching and fine manipulation are involved (1114301s.htm). Amputations through the proximal phalanx often result in extensor habitus, described above. Metacarpophalangeal joint disarticulation of the index or small finger results in an easily traumatized and visibly prominent metacarpal head. Metacarpophalangeal joint disarticulation of the middle or ring finger results in a "hole in the hand", through which small objects held in the cupped palm can fall. Treatment of either of these scenarios with removal of a metacarpal replaces the original problem with a narrowed palm and reduced  torque grip strength.

Fingertip injuries other than amputations still carry all of the painful and otherwise disabling complications of finger amputations. Nail deformities, tender scars and nonunion (1121100s.htm) are all difficult treatment issues. Pediatric fingertip crush injuries are common, and severe injuries involving a sterile matrix laceration with a tuft fracture are frequently missed in children (DF). These injuries require meticulous nailbed repair to avoid deformity.

Foreign bodies in the hand are most often symptomatic when they involve the distal phalanx (BK). Removal of foreign bodies which are lodged entirely beneath the surface should be performed with tourniquet control and surgical anesthesia.  Otherwise, a common result is that the area of a foreign body is incised, attempts at retrieval unsuccessful, and the problem is compounded by the inflammation and scarring from instrumentation. Foreign bodies are most likely to give rise to problems when they are composed either of organic (wood, plant thorn, etc.) or highly contaminated materials. Phoenix date palm thorns frequently produce a chronic sterile inflammatory reaction and require radical debridement and extensive synovectomy as the primary treatment (DV). Foreign body entry points at the dorsal surfaces of the metacarpophalangeal or interphalangeal joints, or at the palmar flexion increases of the fingers are at particular risk for contamination of tendons and deep space infections. Chronic symptomatic foreign body problems require tumor like excision and synovectomy, not incision and removal (foreign.htm).

Thermal burn injuries of the upper extremity result in stiffness of the hand, and the best prevention for this is early active motion within two weeks of injury (CQ). This goal is difficult to achieve reliably, because depth of burn may be difficult to assess, and areas which require skin grafting must be immobilized for at least one week after surgery.  When possible, the goal is early definitive wound closure with full thickness or tangential excision and skin grafts or flaps, followed by motion at the earliest possible opportunity. The ultimate disability in hand function is thought to relate to the time required to achieve wound closure, although this point is controversial (CY). Burn injuries can cause lifetime problems which can not be cured with any amount of surgery and therapy, and the surgeon must strive to promote realistic, achievable goals (CW). Compartment syndrome (AS, BB), contractures (CT) of web spaces, extensor and flexor services, hypertrophic scars and heterotopic ossification are common complications. Although rare, surface contact burns over the course of the brachial artery may lead to ischemic limb loss (AD). Pediatric burns of the hand more commonly involve an isolated contact burn of the palm, particularly in infants, sustained when a child grabs a hot object such as a curling iron, and then grips even more tightly in response to pain. As for burns in other areas, excision and grafting is indicated if the injury is expected to take longer than three weeks to heal, but in this instance, contractures requiring additional reconstructive procedures are common (CT). Pediatric hand burns have the most favorable outcome when managed in a specialty treatment program (DE).

Frostbite (EI) injuries of the hand have a wide variety early treatment recommendations, but rapid rewarming is standard. Traditional management is observation and delayed amputation (frost.htm). Bone scan may help distinguish between unsalvageable and potentially salvageable regions. Early operation may provide marginal tissue with a new blood supply and preserve both function and length in the upper extremity.

Electrical injuries of the the upper extremity may produce extensive deep tissue injury, compartment syndrome,  as well as delayed tissue necrosis and delayed vascular thrombosis (EM) . Early exploration and decompression of deep compartments, vascular graft reconstruction of segmental defects and early free microvascular flap reconstruction reduce amputation rate and shorten recovery (EK, EL, DM, EO) . Even with optimum treatment, long term sensory loss is common and remains and unsolved problem (EJ).

Degloving injuries of the hand most often result from the hand being caught in moving machinery.  When possible, microvascular replantation of the degloved tissues probably gives the best final result, although sensory recovery is difficult to achieve even with this technique (CB).  If replantation is not possible, efforts to salvage a crushed avulsed flap are usually unrewarding, and primary excision and resurfacing with a graft or flap (crush.htm) is indicated to avoid a prolonged course of progressive flap loss, delayed healing, infection and stiffness.

Mangling hand injuries result in a wide zone of mechanical injury, usually involving all tissue components of the hand. Mechanisms include crush, blast, ballistic, traction and avulsion injuries. All complications are possible, and these are at particular risk for delayed healing, marginal wound necrosis (15050.htm), infection (1434502x.htm), delayed thrombosis, prolonged swelling, compartment syndrome (AS, BB), intrinsic muscle contractures (1505201.htm), nonunion (gsw.htm, percmeta.htm), stiffness, and lack of sensory recovery (CB). The initial management plan is critical, as outlined in the next section.

Complications of treatment of severe hand wounds add additional trouble to an already difficult situation.
Failure to proceed with primary amputation:  It is a difficult decision to decide when to attempt replantation of amputated digit or hand.  It is even more difficult and emotionally stressful to decide when to amputate a severely injured hand or digit, particularly when the part in question has at least the appearance of an existing blood supply.  "Saving" a mangled hand may simply burden the patient with a painful useless extremity, a triumph of technique over judgment.  One guide to making this decision is to ask the question "If this extremity looked like this, but was a complete amputation, would replantation be indicated?". If the answer is clearly "no", primary amputation should be strongly considered  (grisly.htm).  The best time to proceed with primary amputation for a mangled extremity is the very first operation. If the surgeon realizes at the time of the first operation that the hand is unsalvageable, but does not amputate, it sets a precedent for false expectations and even greater disappointment than would otherwise be endured. The patient in the family see the bandage, conclude that the hand has been "saved", and will find it much more difficult to accept the fact later that it has not. Although some patients with a saved mangled extremity may decide later to have an elective hand amputation (CK), most will be unable to make this decision even if the hand is a burden and clearly inferior to a prosthesis.

Inadequate debridement: The single common denominator of wound healing complications such as infection, delayed healing, marginal necrosis, and wound breakdown is inadequate debridement.  If the zone of injury can be determined with reasonable certainty, severe wounds should be radically debrided, anticipating the possible need for complex flap closure.  Debridement should remove severely contaminated tissues and all ischemic tissues which cannot be vascularized. This includes crushed flaps, distally based flaps with a length to width ratio greater than one to two, and flaps which are obviously ischemic. Initial debridement should be performed under tourniquet control, and proper initial debridement of severe wounds involves en bloc tumor like excision using scalpel and saw, not curette or irrigation, although these may be used later. The skin of the palm has a primarily perpendicular rather than tangential vascular pattern, and traumatic palmar flaps should be considered for primary excision and alternate resurfacing, as their vascularity is quite unreliable (crush.htm).

Poor timing of wound closure: Traditionally, the timing of closure of severe hand wounds has been classified as primary (immediate), delayed primary (within two weeks), and secondary (after two weeks).  Historically, delayed primary closure was recommended for military and other severe hand injuries. This recommendation is still appropriate when the only available wound closure technique is direct closure or closure with local flaps.  However, the timing of wound closure using distant or microvascular free flaps follows different guidelines. The status of severe open wounds which are candidates for flap closure is classified as acute (prior to the appearance of granulation tissue - usually less than one week), subacute (after the appearance of granulation tissue, before dense scarring - usually one to four weeks), and chronic (usually after one month). Wounds which require flap closure have the lowest complication rate (fewer flap failures, fewer post-operative infections, shorter hospitalization, least number of operations, shorter overall period of disability) when closure is performed in the acute phase and the highest complication rate when performed during the subacute phase (DC, BD, DK, DL, DN, DO). Free flap reconstruction of burn injuries has the lowest complication rate when employed for the reexploration and reconstruction of healed, closed burn injuries (DM).

Technical failure of complex wound closure: Even with adequate debridement, avoidance of using local flaps from potential zone of injury, and careful planning, wound closure may fail.  Skin grafts in the hand may be lost because of inability to provide adequate immobilization, and flaps may be lost when the complex wound dimensions exceed the capability of the flap. Although free flaps tend to be successful or loss on an "all or none" basis, partial free flap loss may occur.  Pedicled flap loss usually occurs at the exact point of critical need for flap coverage (flaploss.htm). However, even a perfectly designed and executed flap cannot obviate the effects of inadequate debridement or poor timing of wound closure.

Complications of replantation: All complications of complex hand wounds can occur following replantation, including tendon adhesions, tendon rupture, neuroma, and delayed healing.  Replantation has additional risk for a number of other problems. Early vascular failure (replant2.htm) of replantation is influenced by mechanism of injury and patient selection. Early failure is more common in smokers (CU), more distal replantation level and in crush and avulsion injuries (DG). Following successful revascularization, venous problems are more likely to result in loss of replantation than arterial thrombosis (AQ, AW). The critical time for failure and for successful salvage is the first four postoperative days (AW). Marginal necrosis or interval gangrene (15050.htm), as with other wounds is due to inadequate debridement or inability to distinguish viable from nonviable tissues in a wide zone of injury. The most common complication of a successful replant is stiffness due to tendon adhesions (AQ). Cold intolerance is uncommon following pediatric replantation, but occurs in most adult replantations (AQ). Aesthetically disturbing fingertip atrophy occurs in nearly half of replanted digits (AQ), due to the effects of incomplete reinnervation and in some cases, late effects of prolonged ischemia (replant2.htm). Lack of sensory recovery is more common in adults than children, when both arteries have not been repaired (CB), and in avulsion injuries (DG). Local vascular complications such as pseudoaneurysm (AE),  arteriovenous fistula (BN), stricture, and late thrombosis may occur as with any vascular repair. Delayed union, nonunion, or avascular necrosis may occur, particularly when the replantation is performed at the phalangeal neck level (BU), because the phalangeal head is covered with cartilage, and has a primarily intramedullary blood supply. Fractures or osteotomies through this level are prone to this complication even out of the setting of replantation (CM). Prolonged incapacitation and multiple operations are typical, with the average patient requiring two or more additional procedures after replantation (CC).  Judgment regarding indications for replantation must include consideration that the poor results after replantation may be much disabling than primary amputation. Functional outcome is significantly worse when replantation involves prolonged ischemia (replant2.htm) or injury in flexor tendon zone II (CU).

Complications of vascular injuries

Missed vascular hand injuries

Ring avulsion injuries range from trivial skin lacerations to arterial or venous disruption to combined injuries in continuity to complete amputation.  The zone of injury is usually greater than would be suspected from casual inspection, and combined vascular and skeletal disruption injuries are often not salvageable despite the external appearance of a simple laceration (ringavul.htm).  When the ring is completely pulled off the finger in association with a circumferential finger wound, the distal soft tissue envelope is usually severely injured, effectively turning the soft tissue sleeve inside out and irreparably damaging the distal part.  For all but the most minor injuries, successful salvage with vein grafts and flaps is unlikely, and even when successful, often results in a stiff, insensate digit.

Partial vascular laceration is the most likely mechanism for persistent uncontrolled hemorrhage, and substantial bleeding may follow a partial venous laceration. As elsewhere, persistent bleeding is better controlled by local pressure than blind clamping, which may result in iatrogenic nerve injuries  (clamp.htm). Late effects include pseudoaneurysm, delayed hemorrhage and delayed thrombosis.

Iatrogenic vascular surgery related hand complications
Graft harvest: Radial artery harvest for coronary artery bypass may result in hand ischemia or superficial radial nerve injury (AG, BR). The incidence of hand ischemia following radial artery harvest may be reduced by the use of preoperative color duplex scanning in addition to care for physical examination.

Dialysis access: Severe hand ischemia occurs in nearly 2 percent of patients undergoing new angio access surgery (AK). This problem is more common in diabetic patients who have had multiple angio access procedures (AI) or who have diabetic neuropathy (BA) . Prompt recognition and treatment is critical to avoid tissue loss and permanent nerve injury. This problem should be suspected when finger pain, numbness or nerve symptoms arise immediately after angio access surgery.  Optimum treatment options include ligation of the fistula, intraoperative duplex scanning guided banding (AJ), or distal revascularization-interval ligation. Neurologic symptoms may arise even if critical ischemia cannot be demonstrated, and recovery of nerve function is unpredictable (BA). Direct nerve compression may result from adjacent access materials (vascular.htm) or hematoma around the side of a vascular suture line (BL).

Bypass surgery: Upper extremity ischemia has been reported as a steal phenomena following axillofemoral bypass graft, and due to emboli after thrombosis of an axillofemoral bypass graft (BF, BQ).

General complications of upper extremity vascular injuries: Ischemic gangrene, chronic ischemia, intrinsic contractures, traumatic aneurysms, arteriovenous fistula, thrombosis and embolism may occur in the hand as elsewhere following vascular injury. Supracondylar fractures of the humerus may result in brachial artery compression or disruption, and post ischemic reperfusion compartment syndrome of the forearm can follow restoration of arterial flow following either closed reduction or vascular repair. Fasciotomy should be considered if ischemic time exceeds two hours, and should be performed if compartment pressures are elevated.

Complications of treatment of vascular injuries

Inappropriate use of techniques to control bleeding in the emergency room can add significant injury. Nearly all bleeding in the upper extremity can be controlled by elevation and direct pressure. Tourniquet use in the emergency room should be limited to a few minutes at most, and ideally only by the surgeon who is going to provide the definitive surgical care. Inflating a tourniquet and then waiting for the hand surgeon to arrive in the emergency room is inappropriate, dangerous and limits future treatment options. Similarly, use of local destructive intervention with clamps, ligature or cautery (clamp.htm) by anyone other than the surgical specialist assuming final care of the patient should be strongly discouraged.

Inappropriate primary call to the vascular surgeon for upper extremity hemorrhage is a common problem. Upper extremity hemorrhage is usually best managed by an upper extremity surgeon. Time permitting, the ideal order of repair of the severely injured upper extremity is debridement, skeletal stabilization, musculotendinous repairs, nerve repairs, and then vascular repairs (flow.htm), all under tourniquet control.  Such an approach minimizes hemorrhage and allows the most precise primary repairs. Unfortunately, a common scenario is that the bleeding arm is first managed by a vascular surgeon who does not provide definitive care of adjacent nerve and musculoskeletal injuries.  In this situation, the vascular injury is repaired, often with a graft, and then the extremity surgeon called in to complete the work.  When the adjacent nerve and muscles are then repaired, the vascular "gap" requiring a graft disappears, and the graft may need to be removed to avoid kinking from redundancy. Similarly, performing only vascular repair, closing the wound and referring to patient for secondary repair of adjacent structure may sacrifice the best opportunity to do a precise primary repair of all structures in the most safe and efficient manner.

Complications of tendon injuries

Missed tendon injuries can occur when either the patient or the initial examining physician fails to appreciate subtle findings.

Partial tendon lacerations (partend.htm) should be suspected when the patient has apparent full motion, but has pain when attempting to use the tendon against resistance.  Consequences of partial tendon lacerations include delayed rupture, scarring with tendon adhesions, triggering and weakness.

Missed finger extensor mechanism injuries may occur because the broad expanse of the extensor mechanism can initially maintain posture until softening from the healing process allows the remnants of support to give way.  Terminal tendon injuries at the distal interphalangeal joint, and central slip injuries at the proximal interphalangeal joint should be suspected when there is a regional injury and pain with attempted extension against resistance, even if the patient has a full active unresisted motion.

Missed finger flexor tendon injuries are less common than missed extensor tendon injuries because of change in the resting posture of the hand  (cuttend.htm). Isolated superficialis tendon injury with an intact profundus tendon produces a subtle change in finger posture, and is easily missed.  Profundus tendon avulsion injuries (profavul.htm) are often unappreciated by the patient, who believes that the finger is simply "jammed", and delays medical evaluation until the best window of opportunity for treatment has passed. If there is significant proximal retraction after profundus avulsion, the flexor tendon sheath fills with blood, and within a matter of days shrinks enough that reinsertion is either impossible or does not result in functional movement.

Missed dorsal hand extensor tendon injuries may occur with little initial functional deficit, either through action of adjacent tendinous junctures, or in the index or small fingers if only one of two (proprius and communis) tendons has been cut. Extensor pollicis longus tendon injuries may be missed because of trick motion through the action of the thumb intrinsic muscles on the thumb extensor mechanism, which may allow interphalangeal joint extension to neutral despite a divided extensor pollicis longus tendon.

Common complications of tendon injuries of the hand include stiffness, contractures, tendon rupture, recurrent adhesions and weakness, and depend on the exact level of injury.
The worst results of flexor tendon injuries occur in injuries located in the flexor tendon sheath extending from the metacarpal head to the middle portion of the middle phalanx - referred to as "zone II" or "no man's land". Even under ideal management, only about half of injuries at this level recover good to excellent function, and fewer have a satisfactory outcome following staged flexor tendon reconstruction with a tendon graft (CJ). Quadrigia syndrome refers to limited excursion of the middle, ring, and small fingers due to tethering connections between the profundus tendons of these fingers.  This may follow a simple flexor tendon injury or be due to adhesions following amputation.

The worst results of extensor tendon injuries occur when injuries are located over the dorsum of the proximal phalanx  or the proximal interphalangeal joint. Loss of proximal interphalangeal joint motion may take the form of a fixed contracture, swan neck deformity, or boutonniere finger. Thin soft tissue cover and poor tolerance of any length change both contribute to poor results at this level.

Complications of the treatment of tendon injuries
Tendon adhesions and are the most common problem following tendon repair. Rupture of a flexor tendon repair occurs in at least four percent of patients following primary flexor tendon repair in zone II with postoperative controlled passive motion (CJ). Stiffness may be due to either or both problems, and it may be impossible to determine the nature of loss of motion, even with MRI.

Mallet finger: Nearly half of patients treated for mallet finger develop some type of complication of treatment.  Complications following surgery are more common, more serious (e.g. deep infection), and more frequently permanent than those arising from splinting alone (BG).

Bowstringing due to incompetence of the flexor tendon pulley system may follow injury or iatrogenic injury during efforts to expose, retrieve, and repair the tendon.  External ring splints to support the tendon pulley system are commonly used, but have not shown to be mechanically effective in preventing bowstringing.

Staged flexor tendon reconstruction using temporary silastic tendon spacers followed by tendon grafts carry all the risks of primary tendon repair.  In addition, staged reconstruction is more likely to result in flexion contractures, and greatly extend the necessary length of incapacitation.

Complications of nerve injuries

Missed nerve injuries

Partial nerve lacerations may be missed because their presentation is not a full blown picture of anesthesia or paralysis.  Such injuries are best treated by a primary repair (prtnerve2.htm).  Delayed or secondary exploration may result in additional nerve injury, because it may be impossible to distinguish between healing tissue, scar tissue, and nerve tissue which either functioning or has the capacity to heal. Late exploration of a healed partial nerve injury usually reveals an amorphous neuroma in continuity, and the only practical option may be to completely divide the nerve, excise the entire neuroma and reconstruct the entire nerve with nerve grafts. This may be difficult to justify when the patient has either retained or recovered partial nerve function

Motor branch injuries are most often missed following small entry deeply penetrating wounds.  The ulnar motor branch in the palm, the median motor branch in the palm, and the posterior interosseous nerve in the forearm may be injured without producing sensory loss and may be missed by casual survey.

Common complications of nerve injuries in the hand as elsewhere include tender neuroma, paralysis, and incomplete sensory recovery.  In addition, upper extremity nerve injuries usually produce some degree of cold intolerance, and are a common trigger for complex regional pain syndrome. Dysesthesia and disuse of the hand may occur, and are best treated with an aggressive desensitization and sensory reeducation program under the supervision of a hand therapist. Median nerve injuries result in a greater loss of hand function than ulnar nerve injuries because the critical contact areas of the hand are affected.

Complications of the treatment of nerve injuries include failure due to repair under tension, repair within a poorly vascularized soft tissue bed, and contractures due to splinting to relieve tension on a tight repair. Patients who have a wide zone of anesthesia must be instructed on self protection from cuts and burns. Contractures from paralysis are avoidable, but must be anticipated and prevented with splinting: untreated, median nerve palsy will result in a first web space contracture, and ulnar nerve palsy will  result in proximal interphalangeal joint contractures of the ring and small fingers.

Complications of fractures and joint injuries

Missed fractures and joint injuries

Scaphoid and hook of hamate fractures are commonly missed, and are discussed below.

Reversed Bennett's fracture is an intra-articular fracture of the base of the small finger metacarpal, usually associated with dorsal and proximal subluxation of the metacarpal shaft due to the unresisted action of the extensor carpi ulnaris tendon. In contrast to intra-articular fractures of the thumb metacarpal base (Bennett's and Rolando's fractures) which have a similar pathologic anatomy (bennett.htm) and good outcome with a variety of treatment techniques (CP), reversed Bennett's fractures are prone to chronic symptoms from posttraumatic arthritis. These fractures are easily missed on plain anteroposterior and lateral x-rays, and presentation is frequently delayed when they are sustained in a boxing injury mechanism.

Phalangeal neck fractures may go unrecognized despite rotation or dorsal translation of the distal fracture fragments, because alignment may look deceptively normal with routine posteroanterior x-rays. The rotated phalangeal neck fracture is unstable, prone to nonunion (CM), and is sometimes referred to as "hangman's fracture" (hangman.htm) because it is easy to miss in children and difficult to treat late.

Missed ligament injuries are usually missed because the patient downplays the extent of injury, only to seek evaluation later because of persistent symptoms.  The most common missed ligament injuries are gamekeeper's thumb and scapholunate ligament injuries, both discussed below.

Complications of common fractures and joint injuries
Intraarticular fractures of the fingers frequently result and stiffness and functional impairment, particularly when sustained during childhood (BZ). Displaced articular fractures should have anatomic reduction and fixation whenever possible.  Even minor degrees of malalignment are usually unacceptable.  Long term problems including degenerative arthritis are common even with optimum initial care.

Pathologic fractures in the hand are most commonly due to enchondroma involving one of the tubular bones. Complications of treatment are more likely with immediate compared to the delayed treatment of the tumor (AB), and the preferred management of pathologic fracture through a benign and tumor is to let the the fracture heal, then return for definitive treatment of the tumor.

Phalangeal  fracture complications: Distal phalanx fractures carry all of the complications previously discussed for fingertip injuries. Displaced distal phalanx fractures (1121100s.htm) may give rise to nonunion if not reduced and provided adequate internal fixation. Phalangeal neck fractures are discussed above. Phalangeal shaft fractures are affected to a much greater degree by associated soft tissue damage and have an overall worse outcome than metacarpal fractures of similar magnitude.  Poor functional outcome is common with phalangeal fractures which are open, comminuted, or associated with either significant soft tissue injury or periosteal stripping - including periosteal stripping performed during open reduction (DX, CG), when there is associated nerve or tendon injury. Only about one in six displaced phalangeal fractures are stable after closed reduction (CG), and redisplacement may occur following temporary Kirschner wire fixation. Angulation results in a zig zag posture due to tendon in balance, resulting in joint contractors to a degree similar to the degree of proximal angulation (0063106S.htm). Outcome is not improved with the use of plate and screw fixation compared to Kirschner wire fixation (CE). Based on outcome studies, a strong argument can be made to refer all finger fractures to a surgeon with specialty training in hand surgery (CF).

Phalangeal joint injuries prone to complications include essentially all interphalangeal joint injuries, because the precision nature of the interphalangeal joints.  It is common for the sprained proximal interphalangeal joint to be stiff, tender, painful and swollen for six to twelve months after injury.  Permanent joint enlargement and flexion contractures are common consequences of even a minor sprain or "jammed finger". Mallet fracture dislocations (mallet.htm) of the distal interphalangeal joint should be distinguished from simple stable displaced mallet fractures, because outcome following conservative management is poor due to joint incongruity. Pure dislocations of the proximal interphalangeal joint (PIPDIS.htm) are most commonly dorsal, usually stable after reduction, and carry about the same outlook has a bad sprain of this joint.  In contrast, palmar dislocations or dislocations with a lateral component are frequently unstable after reduction and are more prone to progressive contractures, angulation, and degenerative joint changes. Fracture dislocations of the proximal interphalangeal joint are usually dorsal with a small volar plate avulsion fracture. These are usually stable if the volar fracture fragment comprises less than one third of the articular surface.  In contrast, dorsal fracture dislocations in which the palmar fragment involves more than one third of the joint surface, palmar fracture dislocations,  and combined dorsal and palmar fractures ("pilon fractures") are intrinsically unstable, and have persistent subluxation (PIPFD.htm).  These extremely difficult injuries may require internal and external fixation, cancellous or osteochondral grafting, and may be unsalvageable.

Metacarpal fractures prone to complications: Metacarpal fractures have fairly predictable healing, but nonunion is more likely in injuries sustained with a crush or blast mechanism. Gunshot injuries of the fingers frequently result in amputation, but similar injuries in the metacarpal area may produce surprisingly little nerve and tendon damage despite severe skeletal injury and risk of nonunion (gsw.htm). Multiple metacarpal fractures are often sustained in crush injury, and the decision must be made between the need for compartment decompression, wide exposure for open reduction and internal fixation versus the use of percutaneous fixation to minimize additional injury (percmeta.htm).

Metacarpal joint injuries prone to complications: Complex dislocations are dislocations in which intraarticular soft tissue interposition provides a block to reduction, also referred to as irreducible dislocations. These most often involve the metacarpophalangeal joints, the home most often involved, and are usually associated with sesamoid interposition (1437308x.htm).  These must be recognized to avoid additional injury from overzealous attempts at closed reduction, and usually require open reduction. Rupture of the thumb metacarpophalangeal joint ulnar collateral ligament, also known as ski pole thumb or gamekeeper's thumb occurs when the thumb is forced into radial deviation.  The extent of injury is frequently not appreciated by the patient and delayed presentation is common.  Results of acute ligament repairs are better than those of late reconstruction (CD), and arthrodesis may be indicated.

Carpal injuries prone to complications

Scaphoid fractures  (scaphfx.htm) Scaphoid fractures are prone to healing problems because of the combination of poor perfusion of the proximal fracture fragment and strong forces across the fracture site from normal wrist mechanics.  Scaphoid fractures may heal in malunion ("humpback deformity"), but delayed union and nonunion are much more common and difficult problems. Left untreated, scaphoid nonunions have a natural progression to a characteristic pattern of wrist arthritis, initially involving the radioscaphoid and capitolunate joints, referred to as scaphoid nonunion advanced collapse, or "SNAC wrist" Unstable, displaced, or proximal fractures are prone to nonunion even with prolonged casting, and should be considered for early open reduction, because the outcome of surgery is more likely to be satisfactory for acute unstable or displaced fractures than for unstable or displaced nonunions. Open reduction, bone graft and screw fixation has as high as a forty percent failure for unstable or displaced nonunions (BW).

Scapholunate ligament injuries occur from the same mechanism of injury as scaphoid fractures. Like scaphoid fractures, these injuries may not be apparent on initial x-rays. Dynamic scapholunate dissociation may be obvious only on kinematic or stress deviation radiographs. Conversely, bilateral benign congenital scapholunate diastasis may be confused with an acute injury if both sides are not compared (0049102s.htm).  Left untreated, scapholunate dissociation has a natural progression to a characteristic pattern of wrist arthritis, initially involving the radioscaphoid and capitolunate joints, referred to as scapholunate advanced collapse, or "SLAC wrist" (sldis.htm) (DW). Treatment options include partial wrist fusion, proximal row carpectomy, and a variety of soft tissue ligament reconstruction procedures. Capsulodesis procedures appear to be more successful than tendon graft procedures, although no current soft tissue procedure reliably corrects scapholunate diastasis visible on x-ray (BY). Injuries associated with scapholunate dissociation or in partial ligament disruption have a better outcome following surgery than those resulting in complete disruption with a static instability pattern (BY).

Perilunate dislocations and fracture dislocations (lunatedis.htm, plfd.htm)are severe wrist injuries which usually result in some degree of permanent wrist stiffness even with ideal management.  These injuries may not be appreciated on casual inspection, the most common report of inadequate evaluation being "something just isn't right".  These injuries require open reduction and internal fixation and frequently require carpal tunnel release for acute traumatic neuritis.

Hook of hamate fractures are often difficult to demonstrate with plain Xrays, and additional evaluation and management may be indicated based on clinical suspicion (1113201xs.htm, hook.htm). Fractures of the hook of the hamate rarely heal with conservative treatment. The problem may mimic a variety of other problems, including carpometacarpal or capitohamate joint disorders. Problems with this fracture include flexor tendon rupture from abrasion against the fractured hook area. Tendon rupture is a significant complication, often resulting in permanent disability despite multiple operations and extensive therapy. Surgery to remove the fractured hook and inspect the tendons and nerves is indicated to minimize these risks.

Forearm fractures prone to complications:

Distal radius fractures account for about one out of every six of fractures seen in the emergency room and three out of four forearm fractures. They are most common in both sexes between 6 and 10 years and in women between 60 and 69 years old. They may be classified by a number of schemes, but no existing scheme correlates well with final functional outcome (CZ). A large number of operative and nonoperative treatment options have been recommended, many of which appear to give comparable results. Operative treatments include external fixation, percutaneous pinning, open reduction, and any combination of these. Poor final outcome is more likely when the fracture is initially very displaced, when the distal radioulnar joint is involved, when the radiocarpal joint is comminuted, when there is residual shortening greater than 2 mm or dorsal angulation greater than 15 degrees. Closed reduction of intra-articular distal radius fractures has a satisfactory outcome in about four out of five cases (BX). However, about one out of three closed reductions redisplace, and only one out of three of fractures which redisplace and require repeated closed manipulation have a good or excellent final outcome (BX). There are conflicting reports regarding the importance of final fracture alignment on function, but one can make the argument to avoid malunion (radmalun.htm) because secondary surgery for distal radius malunion is successful in only three out of four patients (CX). Nonunion (rnonunion.htm, 1441107x.htm) is uncommon, but is more likely following severely displaced fractures because of the possibility of pronator quadratus or other soft tissue interposition. Complex regional pain syndrome (rsd.htm) and finger stiffness occur to some degree in as many as one out of three patients. Loss of motion is also common, but unpredictable. Tendon rupture (AV), early or late, open or closed, relating to fracture displacement, hardware irritation (1441107x.htm) (AP) or ulnar head prominence. Median or ulnar nerve compression may develop early or late following this fracture.  Posttraumatic arthritis is most common in young adults, seen in radiographs of two out of three young patients evaluated years after injury. Fortunately, radiographs do not correlate well with the degree of symptoms, and many of these patients are asymptomatic. Compartment syndrome of the forearm may develop in association with emergency reduction and stabilization of a distal radius fracture with a circumferential cast.  However, compartment syndrome of the forearm may develop after high energy injury distal radius fracture even in the absence of circumferential cast or bandages (BC), and may develop up to 48 hours after the initial injury (AZ). Distal radius fractures in males under 50 years old are at particular risk (BH), probably because these represent a subset of high energy injuries. If clinical examination is unreliable, as in patients who are obtunded or whose symptoms may be masked by narcotics, in hospital observation and or repeated measurement of compartment pressures may be indicated during the first two days after injury. Carpal instability may develop, either as a discrete ligament injury or as a result of changes in the radiocarpal joint angle. Nonunion of associated ulnar styloid fractures is common and usually painless. Prolonged recovery (six to twelve months) is typical, as are long term subjective symptoms, such as pain, fatigue, and loss of grip strength. Such symptoms are reported by about half of patients with a non-compensation related injury; in about four out of five adult patients under the age of 45, and in essentially all patients with compensation related injury. Despite this, three out of four patients on the average have a satisfactory functional result following distal radius fracture.

Both bone forearm fractures in an adult may result in a variety of problems. Complications are more common and prognosis is worse for displaced fractures and for open fractures. On the average, nondisplaced fractures take six to eight weeks to heal, and displaced fractures take three to five months. Satisfactory functional end results may be expected in about eight out of ten patients with nondisplaced fractures and about one half of those with displaced fractures. As many as one half of patients will have obvious loss of forearm pronation, which may or may not be functionally significant. Loss of forearm rotation is most likely when fractures occur in the middle third of the forearm. Synostosis may lock the forearm in a fixed position of rotation. Nonunion occurs in as many as one out of ten patients (1360603x.htm). Nonunion related to technique is more likely when semitubular plates are used, or when less than six cortices are engaged on each side of the fracture. Early protected motion appears to improve the odds of satisfactory final motion. Internal or external fixation is usually indicated for open or very unstable fractures, accepting the risk that postsurgical infection may occur in as many as one out of twenty patients. Proximal forearm fractures are associated with a variety of problems, including nonunion, nerve and tendon injuries and synostosis. One fifth to one half of patients can be expected to have significant permanent loss of forearm rotation. Open treatment of acute fracture or nonunion may be complicated by additional nerve injury or synostosis, more likely when injuries are open or classified as high energy. Synostosis, or cross union between the radius and ulna is much more common in proximal than in distal forearm fractures, occurring in about one out of fifteen patients with proximal fractures. Synostosis is more likely in children, with open fractures, with single incision access to both forearm bones, and following high energy injuries. Results of surgery for correction of synostosis are poor when surgery is performed less than one year or more than three years after injury, and even under ideal conditions, only one in five patients can be expected to regain as much as 50 degrees of forearm rotation.

Longitudinal forearm fracture dislocations (1185902.htm) include three special combinations of injury: Galeazzi fracture-dislocation, Monteggia fracture-dislocation, and the Essex-Lopresti lesion (CC). Galeazzi fracture-dislocation refers to a fracture of the shaft of the radius associated with dislocation of the distal radioulnar joint. Monteggia fracture-dislocation refers to fracture of the ulna with dislocation of the radial head. Each of these fracture-dislocation patterns is best treated with open fracture reduction and closed treatment of the dislocation. Essex-Lopresti lesion refers to longitudinal disruption of the radioulnar interosseous membrane and proximal migration of the radius associated with fractures involving the proximal radioulnar joint, the distal radioulnar joint, or both sites. The most common presentation of Essex-Lopresti is associated with radial head excision for fracture, resulting in ulnocarpal impingement syndrome. Treatment is controversial. When diagnosed acutely in the context of an unreconstructable radial head fracture, Essex-Lopresti justifies use of a temporary radial head implant. Late surgical options include ulnar shortening osteotomy or the developing technique of ligament reconstruction with a tendon graft.

Radial head fractures often appear to be an isolated injury, but are associated with distal radial ulnar joint pathology due to proximal migration of the radius as well as elbow arthritis and loss of elbow motion. Early excision of radial head fractures has a significant complication rate, including proximal migration of the radius, which occurs to some degree in the majority of patients (AC). Efforts should be made to reconstruct rather than excise a fractured radial head.

Skeletally immature forearm fractures and dislocations: "Isolated" radial head fractures in children are often associated with some degree of plastic deformation of the ulna, or "plastic" Monteggia fracture. Chronic pediatric radial head dislocation associated with plastic deformation of the ulna is frequently unrecognized, and requires open reduction and ulna osteotomy in late cases (DA).

Complications of the treatment of fractures and joint injuries have been covered in the previous sections.  The most common of these are nonunion (1360603x.htm, gsw.htm, exfixx.htm), external fixation related infection or fracture (exfixx.htm), arthrofibrosis and capsuloligamentous contractures, osteomyelitis (osteo.htm), tendon adhesions or rupture (1441107x.htm), hardware prominence, exposure, or related fracture (1484602s.htm, stressr.htm), and complex regional pain syndrome (rsd.htm)

Complications of infection: Infections are always considered a complication, and have common presentations in the hand.

Missed diagnosis of infection: Herpetic whitlow, a viral skin infection of the finger pulp, is commonly misdiagnosed as an abscess, felon or paronychia.  Diagnosis is suggested by a prodrome of pain, and early signs of tiny vesicles and itching.  Incision and drainage only prolongs recovery and should be avoided if possible. Missed deep infections (ctpus.htm) of the hand are possible because the dense fibrous compartments within the hand mask swelling and contour changes from deep abscess.  Diagnosis is made based on suspicion, with the caveat that throbbing hand pain which keeps the patient awake at night associated with any other signs of infection indicating deep hand abscess until proven otherwise. Missed severe contamination has been discussed in the previous section on complications of missed complex wounds.

Complications of infections and infections prone to complications: Unsatisfactory results are more likely when hand infections involve anaerobes, Eikenella corrodens or human bites (CH). Quantitative cultures are the single most sensitive and specific predictor of infection following microvascular free flap reconstruction of complex extremity injuries, and should be a routine part of this form of treatment. Complex wounds which are found to have greater than 1000 organisms per cubic centimeter at the time of free flap closure should be treated with return to the operating room, flap elevation, repeated debridement and closure (DJ). Atypical infections (CH) may involve subcutaneous tissues or more commonly tendon sheath spaces. Mycobacteria species, most commonly mycobacterium marinum produce slowly progressive hand infections. Deep space infections from either typical or atypical infection usually follow puncture wounds contaminating tendon sheath compartments or joint spaces. The most vulnerable areas where apparently trivial wounds can contaminate deep spaces are the flexion greases of the fingers and the extension creases on the dorsum of the fingers. Diabetic hand infections, particularly in patients with diabetic chronic renal failure, are common, frequently severe and often result in tissue loss. Hand infections in such patients are frequently more severe than they appear by clinical examination, and the surgeon must have a low threshold for early extensile surgical debridement of the entire zone of inflammation (CA).  Gram negative infections are common, and amputation is a common consequence. Pyarthrosis and septic arthritis of the small joints of the hand is more likely to achieve a poor results if presenting after ten days from injury, or when associated with severe trauma (DB).  The most common scenario for small joint infection of the hand involves clenched fist bite injury (boxer4.htm). Hematogenous seeding resulting in implant infection (1400001S.htm, 1351400s.htm) is an uncommon but catastrophic problem justifying prophylactic antibiotics during high risk procedures for patients who have implants such as silastic joint spacers which maintain a permanent open space around the implants. Tetanus may develop following hand injuries (BO), and is most common in the context of parenteral drug abuse. More commonly, deep soft tissue infections from parenteral drug abuse are polymicrobial, and may present as gas forming infection (ivdagas.htm), necrotizing infection, or suppurative thrombophlebitis (BP). Treatment requires excision of the involved area, wide drainage, repeated debridement, and appropriate parenteral antibiotics.