Surgical management of severe upper extremity injury

INTRODUCTION — Trauma to the extremities represents one of the most common injury patterns seen in emergency medical and surgical practice. Achieving an optimal outcome in patients with severe extremity injuries requires a multidisciplinary approach with oversight by the general or trauma surgeon and commitment from other specialists, including orthopedic, vascular, and plastic surgeons and rehabilitation specialists. In most instances, limb salvage can be attempted even if the patient has a mangled extremity; however, occasionally the patient's injuries are so severe that primary amputation is required and can be life-saving. Complications of surgical treatment for severe extremity injury are common; early recognition and treatment are important to minimize morbidity and mortality.

Surgical management of severe upper extremity injuries is reviewed. The clinical examination, which is structured around the four functional elements (nerves, vessels, bones, soft tissues), and radiographic evaluation of severe extremity injury are discussed separately. Reconstruction of the upper extremity is also reviewed separately. (See "Severe upper extremity injury in the adult patient" and "Surgical reconstruction of the upper extremity".)

The management of severe lower extremity injury is reviewed separately. (See "Severe lower extremity injury in the adult patient" and "Surgical management of severe lower extremity injury" and "Surgical reconstruction of the lower extremity".)

UPPER EXTREMITY ANATOMY

Upper extremity anatomy — The bones of the upper extremity include the humerus, radius, and ulna. The musculature is contained within defined anterior and posterior compartments (figure 1).

The brachial plexus is formed by the ventral rami of the lower cervical and upper thoracic nerve roots (figure 2A-B). It supplies cutaneous (figure 3) and muscular innervation to the upper extremity. The cords of the brachial plexus contribute to each of the five major nerves of the upper extremity (axillary, musculocutaneous, radial, median, and ulnar). The axillary nerve is purely sensory. The radial nerve is vulnerable to injury with humeral fracture since it winds around the humerus between the medial and lateral heads of the triceps.

The upper extremity is perfused by the axillary artery, which is a continuation of the subclavian artery. Near the head of the humerus, the axillary artery gives off the circumflex humeral artery and it continues as the brachial artery (figure 4 and figure 5). The brachial artery passes between the biceps and triceps muscles accompanied by the ulnar and median nerves adjacent to the humerus. The ulnar nerve deviates to pass around the lateral condyle while the brachial artery and median nerve pass to the antecubital fossa, where the artery divides into the radial, interosseus, and ulnar arteries (figure 6). Distally at the wrist, the ulnar artery and nerve and the radial nerve are closely apposed to the ulna and radius, respectively (figure 7).

LIMB SALVAGE VERSUS AMPUTATION — Limb salvage is more aggressively pursued in the upper extremities compared with the lower extremities. Limb salvage can be attempted in most patients even if the patient has a mangled extremity (ie, injury to three of the four functional elements [nerves, vessels, bones, soft tissues]); however, occasionally the injury to the extremity is so severe that primary amputation is required to save the patient's life. In addition, for some patients with multisystem injury, the severity of associated injuries may preclude prolonged procedures for attempted limb salvage. Trauma in the proximal parts of the wrist joint is also usually an indication for limb salvage, despite its multiple risk factors (picture 1). (See "Severe upper extremity injury in the adult patient", section on 'Injury severity scoring' and "Severe upper extremity injury in the adult patient", section on 'Predicting limb loss'.)

In spite of improvements in upper extremity prosthesis technology, overall satisfaction is higher in patients undergoing limb salvage compared with the use of a prosthetic after amputation [1,2]. Following every initial limb salvage attempt, the extremity should be reevaluated in the short term for signs of sensorimotor function and tissue viability. If the limb remains dysfunctional due to extensive nerve damage, revisional amputation may be necessary. However, even in severe cases in which the elbow, forearm, and fingers do not move actively, a degree of function can be achieved (eg, elbow flexion) that provides a reasonable degree of patient satisfaction [3]. When amputation is required, the length of the stump should be left as long as possible for a more successful attachment of a prosthesis. Techniques for upper extremity amputation are discussed elsewhere. (See "Upper extremity amputation".)

SURGICAL MANAGEMENT — The primary goal of surgical management is limb salvage, which is aggressively pursued in patients with severe upper extremity injury. Achieving an optimal outcome in patients with severe upper extremity injuries requires a multidisciplinary approach with oversight by the general or trauma surgeon and commitment from other specialist surgeons.

Patients with life-threatening injuries undergo a damage control approach; a small number of severely injured patients will require primary amputation. Damage control surgery includes splinting, or external fixation of fractures; shunting or ligation of vascular structures; identification and tagging of injured nerves as time permits; and irrigation and debridement of soft tissues to remove gross contamination, foreign material, and devitalized soft tissues. Definitive treatment includes internal fixation, arterial and/or venous reconstruction, decompression or repair of peripheral nerves, and immediate or interval coverage of soft tissues (figure 8). The principles of specific initial management are reviewed in the next sections; reconstruction of the upper extremity is discussed in detail elsewhere. (See "Surgical reconstruction of the upper extremity".)

Damage control surgery — When emergency surgery is indicated to control life-threatening bleeding in the abdomen or chest, extremity fractures should be quickly reduced and stabilized with splinting or in-line traction. Splints can be made in a relatively short amount of time with few complications. Damage control chest or abdominal exploration takes priority over extremity trauma as long as sites of extremity bleeding remain controlled. (See "Overview of damage control surgery and resuscitation in patients sustaining severe injury".)

Tourniquets and dressings placed in the field or emergency department may need to remain in place until life-threatening torso hemorrhage is controlled. Once life-threatening torso injuries have been addressed, the extremity injury can be reassessed. Priorities include definitive control of bleeding sites with vascular ligation or placement of a vascular shunt, debridement of devitalized or grossly contaminated tissue, and quick stabilization of any fractures, if possible [4,5]. Following these measures, the soft tissue wound can be managed with temporary gauze dressings or negative pressure wound dressings. Further plans are made for repeat evaluation once the patient has stabilized in the intensive care unit.

Vascular ligation — Vascular ligation is a reliable method for hemostasis and is used for small vessel injuries. Ligation can be performed for injury to the radial or ulnar artery (but not both) in the forearm in most cases without sequelae. For cases in which both the radial and ulnar artery are injured, reconstruction of at least one artery is required. However, for patients with peripheral artery disease, the surgeon should reconstruct both arteries. In such patients, ligation of either artery may cause intolerance to cold temperatures or a delay in wound healing of the affected upper extremity.

Ligation of major arteries (eg, brachial artery, subclavian artery) is likely to cause ischemia. There are no collateral arteries from the bifurcation of the axillary artery to the subscapular artery, or from the brachial artery to the deep brachial artery. Therefore, any injury or ligation to these regions will easily cause ischemia. Furthermore, ligation of major veins (eg, axillary vein) will exacerbate edema.

Vascular shunting — Temporary vascular shunts are used as a method for damage control for brachial artery injuries or major traumatic amputations of the upper extremity (partial or complete). Vascular shunts can reduce the time of ischemia and reduce the need for fasciotomy [6,7]. The shunt remains in place until revascularization can be accomplished with a permanent vascular graft.

Critical time for reperfusion — The critical time for reperfusion for the upper extremity (arm, forearm) is 8 to 10 hours, which is longer than the lower extremity, which is typically up to 6 hours [5]. However, in one review of 7908 upper extremity arterial injuries, the incidence of amputation was significantly decreased for patients who underwent revascularization within 90 minutes of the injury [8]. Thus, if it seems that the revascularization cannot be achieved expeditiously, the surgeon should use a temporary vascular shunt. Ideally, these temporary shunts are supplanted by a final revascularization within six hours. One retrospective review from a United States trauma center showed that 9 percent of patients with vascular injuries in the upper or lower extremities were treated with temporary vascular shunts [9]. In another review, 25 percent of patients with combined orthopedic and vascular extremity injury were shunted [10].

The critical time for reperfusion for certain hand injuries is much less. The volume of muscle in the hand is much less than in the arm/forearm. Because fingers do not have muscle tissue, reperfusion injury after the delayed revascularization does not occur [4]. In the treatment of an ischemic finger or complete finger amputation, surgeons need not rush to reperfuse the finger(s). Until the time of replantation, amputated fingers are cooled in ice. While the maximum time of cold ischemia is not known, successful replantation has occurred more than 24 hours after amputation [11]. A critical time of 6 to 12 hours for warm ischemia of the digits and 12 to 24 hours for cold ischemia have been proposed. The maximum interval for digit replantation is at most 94 hours after the injury [12]. With finger amputation, some surgeons administer aspirin rectally in the emergency department with the expectation that it will help prevent perioperative thrombosis [13]. However, there is no evidence supporting this practice.

Debridement and irrigation — Once vascular injuries have been controlled, necrotic tissues, contaminated substances adhering to the wound site, and foreign bodies are removed from the surgical wound.

Although ejected tissues are an essential component that can be used for the reconstruction of the upper extremity, such as large extruded bone fragment or cartilage, these tissues should not be returned to the wound if they are contaminated (picture 2).

Any previously placed tourniquets should be released during wound debridement, which aids in the identification and excision of necrotic tissue. Contaminated tissues that are not perfused have an increased risk for infection. Wounds are thoroughly washed with saline.

With severe upper extremity injuries, the wound is reevaluated every 24 to 48 hours. Serial debridement is sometimes needed.

Fracture management — Once a fracture is identified, it is reduced as much as possible and splinted. If an open fracture is suspected (algorithm 1), the patient should be taken to the operating room to debride and stabilize the fracture (usually with external fixation) either after life-threatening injuries have been managed or concurrently while less severe chest, abdominal, or head injuries are being addressed [14].

The timing of definitive stabilization of fractures depends upon the nature and severity of the fracture (table 1) and the presence of significant vascular or soft tissue injury. (See "Surgical reconstruction of the upper extremity", section on 'Fracture stabilization'.)

Primary fracture management — Splinting, external fixation, and internal fixation can all be used for primary fracture management.

External fixation, which stabilizes fractures or dislocations, is useful for damage control of upper extremity injuries (algorithm 1) [15]. External fixation of unstable fractures also reduces swelling. External fixation is also used when the soft tissues are in poor condition, such as in fractures accompanied by a vascular injury or an open fracture with a contaminated wound, until the wound is stable enough for definitive internal fixation [16].

Many external fixators stabilize the fracture by bridging several fracture fragments and sometimes even a joint. Fixators with a hinge structure provide patients with joint mobility, preventing joint contracture. Although most external fixators are used temporarily, some devices, such as the Ilizarov fixator (figure 9), are designed to be used for definitive fixation. (See "Surgical reconstruction of the upper extremity", section on 'Ilizarov technique'.)

Definitive fracture fixation — Definitive fixation is usually performed with an internal fixation. Rarely, an external fixation, such as osteosynthesis with Ilizarov fixator, is conducted as a definite fixation.

Early internal definitive fixation is often avoided (open or closed fracture) because of concern over possible development of infection and nonunion [17-19]. Because the rate of deep infection is low for the upper extremity, many upper extremity surgeons tend to perform definitive internal fixation and coverage, except for heavily contaminated wounds [20-23]. This concept is called the "fix and flap approach," which shortens the entire treatment period and enables the patient to undergo early rehabilitation [24]. This practice contrasts to the lower extremity, for which definitive fixation is often delayed.

A fracture reduction procedure, termed osteosynthesis, aligns the bone and fixes the fracture in position using implants, such as plates, screws, and intramedullary nails. When performed properly, internal fixation leaves no gaps between the bones. However, if necessary, bone shortening or grafting can be performed to eliminate gaps (picture 1). The humerus can be shortened up to 4 cm without seriously affecting function [25]. Bone grafting is performed simultaneously when gaps between fragments are caused by fracture comminution. Bone defects less than 6 cm are treated by nonvascularized autogenous bone grafting (algorithm 1), and those 6 cm or more are treated with bone transport or vascularized bone grafting [26,27]. These additional techniques and specialized bone reconstruction procedures are discussed separately. (See "Surgical reconstruction of the upper extremity".)

Specific procedures for definitive fixation

●Osteosynthesis of finger fractures – A distal phalangeal fracture is a common injury of the fingertip and sometimes occurs as an open fracture accompanied by dislocation of a nail and rupture of the nail bed. Most of these fractures are reduced anatomically by restoring the nail plate. The fracture is usually splinted for several weeks until the union of the fracture, but open fractures sometimes result in nonunion. Although distal phalanx nonunion does not seem to be clinically severe, it can cause an abnormal appearance, pain when pinching, and nail deformation [28]. Fractures proximal to the tuft are fixed with multiple Kirschner wires (K-wires) to prevent nonunion caused by rotational instability. Some authors prefer to fix these fractures with screws, which provide similar rigidity and clinical results to those that are fixed with K-wires [29]. When using K-wires for the fixation of distal phalanx fractures, two or more K-wires can shorten the time of union [30]. (See "Proximal phalanx fractures" and "Distal phalanx fractures" and "Middle phalanx fractures" and "Overview of finger, hand, and wrist fractures".)

In the middle and proximal phalanx, more than half of the bone is surrounded by tendons. Thus, any intervention can cause postoperative tendon adhesions. Fractures of the middle and proximal phalanx are usually fixed by K-wires. These are inserted so they do not impede joint motion and tendon excursions. As alternative procedures, screws and plate fixation are used to treat spiral or comminuted fractures. With any method, fixation enables early exercise to prevent postoperative tendon adhesions. After fixation, the surgeon verifies that the fracture was reduced without any remaining rotational deformity by having the patient gently flex his or her fingers.

●Osteosynthesis of metacarpal bone – Methods to treat metacarpal fractures differ depending on the fracture site. Metacarpal neck fractures, which are the most common, have a large angular range of bending deformation, which increases in the more ulnar fingers. Many fractures can be treated with closed reduction, followed by fixation with a splint. If the fracture is unstable because of comminution, or multiple fingers are affected, percutaneous pinning is performed.

Metacarpal neck fractures have a risk for extension contracture at the metacarpophalangeal joint. Thus, a splint is used postoperatively to keep the metacarpal joint in a flexed position, which stabilizes the fracture as well as prevents contracture. (See "Overview of metacarpal fractures" and "Metacarpal head fractures" and "Metacarpal base fractures" and "Metacarpal shaft fractures" and "First (thumb) metacarpal fractures".)

Many metacarpal shaft fractures are treated surgically. With the bending motion of the fingers, a tensile force acts on the dorsal side. This force can be relieved by fixation with a dorsal plate, which is also used in the treatment of spiral fractures. Many proximal metacarpal fractures are associated with dislocation of the carpometacarpal joint. As joint mobility contributes to the exertion of a strong grip, any remaining subluxation or deformity will cause a decrease in grip strength or pain; thus, the fracture-dislocation should be reduced precisely. Fracture-dislocation is usually fixed with K-wires because a splint alone cannot maintain the reduced position.

●Treatment of carpal bone fractures and dislocations – The biomechanics and unique anatomic features of carpal bones need to be taken into consideration when planning osteosynthesis. Scaphoid fracture is the most common carpal bone fracture and often results in nonunion due to a combination of biomechanical forces that will cause a distal scaphoid fragment to flex when loaded by the wrist, as well to disturb its distally inserted blood supply, which is disadvantageous for healing. To prevent nonunion of the scaphoid, many surgeons prefer fixation with a screw, which stabilizes the fragments, compared with cast fixation that often requires several months of immobility for healing. The screw must be embedded in the bone and should not protrude beyond the joint surface. The long axis of the screw should be perpendicular to the fracture line, and the direction of the screw should be determined based on the fracture type [31]. With high-energy trauma, the association of carpal ligament injury results in perilunate dislocation. Treatment of perilunate dislocation is performed with a combination of fixation of the scaphoid fracture and suturing of the ruptured ligaments. (See "Overview of carpal fractures" and "Triquetrum fractures" and "Lunate fractures and perilunate injuries" and "Scaphoid fractures" and "Trapezium and trapezoid fractures" and "Capitate fractures" and "Pisiform fractures".)

●Osteosynthesis of forearm fractures – The radius and the ulna are connected by the interosseous membrane and several ligaments. These anatomical structures enable rotation of the forearm [32]. If either structure develops a deformity, the range in forearm rotation will be considerably decreased. Therefore, anatomic reduction and rigid fixation are necessary for restoring forearm function. Thus, forearm shaft fracture is treated with a plate, which resists extrinsic rotational forces. (See "Radial head and neck fractures in adults" and "Midshaft ulna and radius fractures in adults" and "Distal radius fractures in adults" and "Proximal fractures of the forearm in children" and "Distal forearm fractures in children: Diagnosis and assessment" and "Distal forearm fractures in children: Initial management" and "Closed reduction and casting of distal forearm fractures in children".)

A distal forearm fracture is a common fracture that occurs mainly in older adults with an incidence that appears to be increasing because of the increase in the number of active older individuals [33]. The use of a variety of volar locking plates has contributed to improved outcomes for distal radius fractures [34]. However, the inappropriate use of these plates can cause complications such as postoperative flexor tendon ruptures, extensor tendon ruptures, and carpal tunnel syndrome [35,36]. Most distal radius fractures lie about 1 cm proximal to the radiocarpal joint and can be securely fixed with any volar locking plate [37]. However, treating fractures occurring near the radioulnar joint with a locking plate is difficult, and an external fixator or a bridging plate is a better option (image 1). While triangular fibrocartilage complex (TFCC) injuries, which are often associated with distal radius fractures, are usually initially treated with a cast, TFCC injuries with radioulnar joint instability are sometimes treated surgically.

●Elbow dislocation – The elbow joint consists of the humeroulnar and humeroradial joints, which aid in the flexion and extension of the elbow. The proximal radioulnar joint contributes to forearm rotation. Simple posterior dislocation is treated with manual reduction, followed by external fixation with a splint. However, unstable injuries, such as transolecranon dislocation and posterolateral rotatory instability, cannot be maintained with reduction and are treated surgically [38]. When an intra-articular fracture is concomitant with the dislocation, it is treated surgically to avoid the presence of gaps or step-offs in the articular surface.

●Osteosynthesis of humerus fractures – Treatment of humeral fractures differs depending on the affected site.

For distal humerus fractures, nonsurgical treatments sometimes result in nonunion because of the vulnerability of the metaphyseal fragments to a shearing force. However, this applies only to adults, because the speed of bone union is much higher in children. Therefore, in adults these fractures are often treated by fixation using two plates with a wide skin incision. Although this procedure is standard, there is still a high incidence of postoperative ulnar nerve palsy [39,40]. In comminuted fractures of the distal humerus in older patients, some surgeons prefer primary arthroplasty with a semiconstrained prosthesis, rather than osteosynthesis, because the plating system cannot ensure rigid fixation of the osteoporotic fragments [41]. The treatment of distal humeral fractures in children is discussed in more detail separately. (See "Epicondylar and transphyseal elbow fractures in children" and "Supracondylar humeral fractures in children" and "Elbow anatomy and radiographic diagnosis of elbow fracture in children".)

In humeral shaft fractures, there is a risk for radial nerve paralysis because the radial nerve passes just above the fracture site and deviated bone fragments will strain the nerve. Spiral fractures, which are often caused by the action of throwing, are usually managed nonoperatively. A comminuted or a transverse fracture should be fixed with a plate or an intramedullary nail. Some surgeons prefer not to use an intramedullary nail because it requires an incision of the rotator cuff, which is adherent to the proximal humerus. (See "Midshaft humerus fractures in adults".)

Many proximal humerus fractures can be managed nonoperatively, but fractures that include fragments that are not in contact with each other are fixed with a locking plate. If a gap remains on the medial side of the fracture after the reduction and correcting bone losses, nonunion may occur postoperatively. Therefore, osteosynthesis with a locking plate is performed to shorten the humerus at the fracture site [42]. If fixation with a locking plate is not feasible in fractures with comminuted humeral head or shoulder dislocation, reverse shoulder arthroplasty is an option [43]. (See "Proximal humeral fractures in adults".)

Revascularization — Prolonged ischemia (>8 hours) caused by vascular injuries is an indication for amputation. Revascularization within ideally six, but up to eight, hours of the injury prevents the nerve and muscle from further damage, improving the chance for limb salvage. Vascular reconstruction should be undertaken after external fixation to prevent disruption of the repair due to the unstable bony framework. If the stabilization process is predicted to take a prolonged time, use of a temporary arterial shunt will limit the duration of extremity ischemia. (See "Surgical and endovascular techniques for aortic arch branch and upper extremity revascularization".)

Vascular grafts are used when there is a defect between the stumps of the artery or when there is too much tension in the connected arteries. In some crush injuries, the artery near the wound includes severe intimal damage in which a graft must be used as a substitution for the injured vessel to prevent postoperative thrombosis. In regards to the graft, either a cephalic or saphenous vein is used for artery reconstruction of the forearm; veins in the dorsal hand or cutaneous veins harvested from the forearm are used for the hand and fingers (picture 3).

When performing revascularization proximal to the wrist joint, arterial repair is performed before venous repair to allow anaerobic metabolites and potassium that have accumulated in the periphery to be flushed out of the limb [44]. Vein injuries are usually repaired with ligation, but a vein with a large diameter would be better repaired with anastomosis to prevent congestion of the distal tissue and peripheral swelling. In degloving injuries, venous anastomosis is performed with returning the injured skin to its original site. Venous anastomosis restores the collapsed venous circulation in the degloved skin and prevents congestion and necrosis of the degloved skin.

A "flow-through flap" is an alternative form of revascularization that can be used to reperfuse the limb and simultaneously cover soft tissue defects [45]. With this free flap, both the proximal and distal ends of the vascular pedicle are anastomosed to provide blood flow to distal tissues and the flap.

Upper extremity fasciotomy — Patients with severe crush injury or edema caused by fractures or dislocation can develop compartment syndrome. A rise in the compartment pressure is an indication for fasciotomy to prevent muscle necrosis and nerve damage. The many etiologies for acute extremity compartment syndrome and its diagnosis are reviewed separately (table 2). (See "Pathophysiology, classification, and causes of acute extremity compartment syndrome", section on 'Traumatic injury' and "Acute compartment syndrome of the extremities".)

Prophylactic fasciotomy should be performed if ischemia has been present for more than three hours. The fasciotomy wounds are left open until swelling in the extremities is reduced and there is evidence for healing. The wounds are then closed. Further details of upper extremity fasciotomy are discussed elsewhere. (See "Upper extremity fasciotomy techniques".)

Nerve exploration and repair — Nerve injury occurs in about 3 percent of all upper extremity trauma. The energy of the trauma does not affect the occurrence of the nerve injury, but specific trauma mechanisms, such as motorcycles accidents, are more likely to cause nerve injury in the upper extremity [46]. In addition, humeral fractures, ulnar fractures, and arterial injuries are associated with nerve injuries. Therefore, in the presence of these findings, surgeons should search the nerve carefully [46].

Nerve injury is classified based on severity (table 3). Exploration and repair of acute nerve injury occurs mainly for neurotmesis (irreversible damage to the axon, myelin sheath, and surrounding stroma) but can be conducted for axonotmesis (local irreversible damage of axon and myelin sheath, but intact surrounding stroma) (algorithm 2). (See "Traumatic peripheral neuropathies", section on 'Classification and pathophysiology'.)

While axonotmesis can often heal without surgical repair, discriminating between neurotmesis and axonotmesis can be difficult immediately after injury, particularly with closed injuries. In addition, the recovery period from serious injuries can be prolonged, delaying evaluation. For these reasons, if there is the slightest indication that neurotmesis may have occurred, the nerve should be explored surgically. As an example, nerve exploration is likely indicated whenever radial nerve paralysis is accompanied by a humerus shaft fracture [47]. In a systematic review, more than one third of patients with a high-energy closed fracture who underwent surgical exploration of the nerve had complete nerve rupture [47]. With appropriate exploration, the surgeon is better equipped to determine an optimal course of action for nerve injury treatment.

The method of nerve repair depends upon the extent to which the nerve is affected. A nerve that is stuck between bone fragments or adherent to soft tissues is released via neurolysis. A divided nerve is repaired by suturing, with or without a graft (algorithm 2). Severed nerves are repaired with end-to-end 9-0 nylon. If there is a large defect between the disconnected stumps of the nerve, or the tension of the suture is too strong, nerve grafting is performed. Gaps less than 3 cm can be bridged using a conduit (eg, tubular collagen, autologous vein) or autograft. A defect of 3 cm or more is bridged using an autologous nerve graft, which is harvested from the sural nerve or medial forearm sensory nerve, depending on the diameter of the affected nerve. Some recommend vascularized nerve grafts for long span nerve defects (about 10 cm or more) as a more effective form of repair [48,49]. Unrepairable nerve injuries, such as preganglionic brachial plexus injuries, are reconstructed with free muscle transfer. The procedures for nerve reconstruction in the upper extremities are discussed elsewhere. (See "Surgical reconstruction of the upper extremity" and "Surgical treatment of brachial plexus injuries".)

Wound coverage and reconstruction — Wounds should be closed or covered as soon as possible for the best functional outcome because open wounds limit the patient's ability to participate in physical therapy. Interim wound care is discussed below. (See 'Wound care' below.)

The strategy for selecting the type of wound coverage is based on the concept of the reconstructive ladder or elevator [50]. This concept suggests that, according to the site and condition of the injury, the most imperative and sufficient skin coverage should be performed, not the simplest one. Wounds that cannot be closed primarily will require skin grafting or flap reconstruction. Different from skin grafting, flap coverage does not form a robust scar, minimizing contracture of the joint and adhesions in covered tendons. Flap coverage with vascularized subcutaneous soft tissue helps restore tissue with poor vascularity as is the case with exposed bone, which requires vascularized soft tissue to engraft itself. Flap coverage is also effective for covering of mobile structures, such as joints and tendons. Flaps are also useful for fingertip defects because they can reconstruct the soft pulp of the fingertip and still maintain touch sensation. Details of flap coverage for soft tissue defects in upper extremities are discussed elsewhere. (See "Overview of flaps for soft tissue reconstruction" and "Surgical reconstruction of the upper extremity", section on 'Soft tissue coverage'.)

Timing of coverage — The optimal timing for soft tissue coverage of open wounds following trauma has been a subject of debate among surgeons. In the past, the wound coverage was delayed after open injury management to avoid enclosing a source of infection. However, clinical experience has shown that infection rates depend on the level of contamination [51,52]. For noncontaminated wounds, early definitive fracture fixation concomitant with flap coverage ("fix and flap approach") has become established [24]. The benefits of early flap coverage are improved oxygenation and enhanced delivery of antibiotics and immune mediators to the injury site, which accelerates healing and reduces the risk of infection [53-55].

Although the concept of early skin coverage including the "fix and flap approach" may seem like a logical treatment, its application is limited depending on the clinical setting. Early coverage is not always able to be accomplished for a variety of reasons. In some situations, serial debridement and delayed coverage may be the more reasonable option because tissue damage can progress after the initial debridement. Types of trauma that often require serial debridement include burn injury, high-pressure injection injury, crush injury, electrical injury, and some penetrating injuries (picture 4) [56]. Free flap reconstruction is also avoided for patients who require postoperative anticoagulation therapy. In addition, a limited number of facilities have the technical capabilities to provide on-demand microsurgery following trauma.

POSTOPERATIVE CARE AND FOLLOW-UP — The postoperative course for patients with upper extremity injury is highly variable depending on the nature and severity of extremity injury, associated injuries, and the patient's comorbidities. Postoperative management of severe upper extremity trauma includes wound management, measures to prevent complications (eg, venous thromboembolism), and rehabilitation.

Rehabilitation is essential in the process of restoring function and has positive psychological effects. Ambulation may be challenging in patients with concomitant upper and lower extremity injuries and can be painful. Early ambulation can improve the patient's mental disposition in addition to reducing the risk of pneumonia and deep venous thrombosis.

Pain control is also an important objective for a trauma patient. Even when the surgery is performed appropriately, joint contracture can result if a patient avoids mobilization of his or her joints because of postoperative pain.

Activity and rehabilitation — The goal of physical and occupational therapy, which uses active and passive exercise, splinting, and patient education, is to maximize limb function and minimize post-traumatic contracture. (See 'Joint contracture' below.)

Trauma impairs venous and lymphatic outflow from the injured site leading to limb edema, which generally occurs in all cases. Edema can lead to scarring through fibrosis of the subcutaneous tissues, which diminishes the range of motion of joints and attenuates tendon excursion, contributing to contracture formation. Active and passive exercises from an early stage of rehabilitation, supported by rigid fixation of the fractures, help prevent contracture. Using a splint to fix the limb in proper position (figure 10), especially with fingers, also helps prevent contracture.

Muscle fibrosis and the sequelae of compartment syndrome in the intrinsic muscles and adductor muscle may cause the hands and fingers to assume an inappropriate position, referred to as the intrinsic minus position, wherein the metacarpophalangeal (MCP) joint is in hyperextension, the proximal interphalangeal (PIP) and distal interphalangeal (DIP) joints are in a flexed position, and the thumb is usually contracted in an adducted position. Without an appropriate intervention, the position gradually becomes irreversible and ultimately causes rigid contracture of the fingers.

Wound care — A closed wound is managed by gauze dressing. Open wounds are initially packed with wet gauze dressings. The surgeon may also use negative pressure wound therapy (NPWT).

NPWT is used as a temporary coverage for the open wound as a means for wound management in between serial debridement. NPWT promotes granulation, which serves as the base for skin grafts, and reduces the incidence of infection via elimination of exudates (picture 5). However, an extended duration NPWT can introduce scar tissue, and as such, the duration of treatment should be minimized to the extent that is possible [57,58]. (See "Negative pressure wound therapy".)

The presence of an increased volume of exudate, suppuration, redness, and swelling of surrounding tissues may be signs of infection indicating the need for additional debridement. (See "Surgical reconstruction of the upper extremity".)

Antithrombotic therapy

VTE prophylaxis — The incidence of venous thromboembolism (VTE) following upper extremity injury is overall low in contrast to that of pelvic or lower extremity injury [59]. In a review of state inpatient data from four states in the United States, the incidence of VTE in patients with upper extremity trauma was 2.6 percent [60]. Elbow dislocation and humerus fracture increased the risk of VTE as did associated trunk injuries.

The most commonly affected vessel in the upper extremity is the axillo-subclavian vein, mainly related to the placement of intravenous vascular devices [59,61-63].

Although there are no specific measures for preventing VTE following isolated upper extremity injury, early ambulation and exercise along with avoidance of venous access devices in the affected upper extremity can help prevent its occurrence. For multiply injured trauma patients, pharmacologic VTE prophylaxis in addition to these measures is indicated. (See "Venous thromboembolism risk and prevention in the severely injured trauma patient".)

Antiplatelet therapy — As discussed above, preoperative administration of rectal aspirin (Buncke protocol) has been proposed for digital revascularization [13], but there is no evidence that suggests preoperative rectal aspirin administration prevents postoperative thrombosis or necrosis. (See 'Critical time for reperfusion' above.)

Following revascularization of traumatic injury, we suggest antiplatelet therapy (eg, aspirin, 325 mg daily) for 6 to 12 weeks following revascularization until the intima heals at the anastomotic sites. Although there is no literature on the need for or effectiveness of antiplatelet therapy following extremity vascular injury and repair, the use of antiplatelet therapy following repair of vascular injury is based on known mechanisms of action of these medications and extrapolation from similar regimens in patients having undergone vascular procedures for age-related vascular disease.

Systemic anticoagulation has no proven role for maintaining vascular graft patency, but it may be used transiently in the postoperative period if there is concern for residual distal thrombus. Dextran has been used in the setting of venous reconstruction, although the benefits of this approach have not been rigorously studied [64].

Surveillance after vascular repair — As with any vascular reconstruction, surveillance of the vascular reconstruction, ideally with duplex ultrasonography, should be performed at 3, 6, and 12 months postoperatively, and then annually thereafter.

COMPLICATIONS — Complications from severe upper extremity injury are common and can be life- or limb-threatening, and, thus, early recognition and treatment are important to minimize morbidity and mortality. Complications associated with severe upper extremity injury include wound complications (wound breakdown), infection (surgical site infection, osteomyelitis), venous thromboembolism, rhabdomyolysis, myoglobinuria (crush injury, ischemia-reperfusion, extremity compartment syndrome), nonunion, and heterotopic ossification. The threshold for performing extremity fasciotomy is low in patients with severe extremity injury.

Infection — Although infection after trauma in the upper extremities is lower compared with that in the lower extremities, surgical site infection (SSI) contributes to prolonged hospitalization and additional medical expenses, which emphasizes the importance of prevention.

In a retrospective study of 1300 elbow fracture surgery cases, 4 percent of the patients had SSI, with Staphylococcus aureus being the most commonly detected organism (59 percent) [65]. Smoking was associated with high infection rates.

In spite of adequate preventive measures, infection can still occur [66,67]. If antibiotics cannot reach the injury site because of reduced blood flow, an abscess may form, which will require incision and drainage. Treatment can be further complicated if infection involves the bone marrow, termed pyogenic osteomyelitis. This requires thorough curettage of the bone and resection of the necrotic lesions, followed by reconstruction of the resected bone and soft tissue. If infection becomes uncontrollable, limb salvage may no longer be possible, necessitating amputation. (See "Surgical reconstruction of the upper extremity", section on 'Repair of nonunions' and "Osteomyelitis associated with open fractures in adults", section on 'Antibiotics after open fracture'.)

Rhabdomyolysis — Crush injury or compartment syndrome can lead to rhabdomyolysis. Long-term compression of the tissues and muscles in crush injuries causes muscle necrosis and rhabdomyolysis. This is less common with upper extremity injury than lower extremity injury due to less muscle mass, but it can occur especially with prolonged ischemia time involving the entire upper extremity. Release of myoglobin and potassium from necrotic muscle can lead to kidney and cardiac dysfunction. Adequate hydration is important to prevent sequelae. If compartment syndrome is concomitant with crush syndrome, the condition is treated with fasciotomy [68]. (See "Severe crush injury in adults" and "Crush-related acute kidney injury" and "Acute compartment syndrome of the extremities".)

Nonunion — Nonunion of a fracture is defined when a union cannot be verified by radiography after six months have passed from the occurrence of the fracture. The incidence of a nonunion in upper extremity fractures is estimated to be less than 10 percent [69]. The most common sites of nonunion in the upper extremity are the humerus shaft, the forearm shaft, the scaphoid, and the distal phalanx, but nonunion can occur at any fracture site.

Nonunion has several causes, which sometimes occur in combination. These include a reduced blood supply to the fracture site (ie, ischemia) and inappropriate fixation of the fracture fragments with the presence of a gap between bone fragments after reduction/fixation. Nonunion caused by ischemia is usually categorized as oligotrophic or atrophic nonunion, in which radiography results show either poor or absent callus formation at the fracture site, respectively. A lack of a fixation strength at the fracture site causes instability, with excessive formation of callus, causing a hypertrophic nonunion. Treatments are chosen based upon the type of nonunion (algorithm 3). (See "Surgical reconstruction of the upper extremity", section on 'Repair of nonunions'.)

Joint contracture — Joint contracture is one of the causes of functional impairment seen after treatment of an upper extremity trauma.

Early intervention to prevent joint contracture is important because the treatment of contracture is particularly challenging. Preventive methods include fasciotomy, early mobilization, and appropriate splinting. Early mobilization can relieve swelling by promoting venous and lymphatic return, by expanding the range of joint motion.

Appropriate splinting protects immobile joints and prevents contractures from occurring in inappropriate positions. Splinting is performed when early mobilization is not possible because of pain in the affected joint or an injury to it such as a comminuted fracture. Damaged and adjacent joints in fingers are usually fixed by splints, holding the fingers in the intrinsic plus and thumb in the abducted position. However, temporary fixation with Kirschner wires is sometimes used as an alternative to splinting during the initial surgery to prevent joint contracture.

Heterotopic ossification — Heterotopic ossification (HO) is a pathological condition that is characterized by the formation of bone in soft tissues or joints. It occurs in patients who had severe traumas such as musculoskeletal, spinal cord, or traumatic brain injury. In addition to inflammatory changes, genetic mutations in bone morphogenetic protein have also been considered as triggers of HO [70]. In the process of HO, mesenchymal osteogenic precursor cells are activated and deposit calcified bone in soft tissue.

In the upper extremity, the elbow is a common site for the development of HO. It reduces the range of movement of the elbow joint, which severely hinders the function of the affected upper extremity. In a systematic review, the incidence of postoperative HO at the elbow was 13 percent [71]. In another study from two level 1 trauma centers, 7 percent of patients who had surgery for elbow fractures experienced postoperative HO [72]. Patients in whom surgery was delayed a week after their injury had a higher risk of developing HO. In addition, long-term mobilization (more than two weeks) contributed to an increased risk of developing HO [72].

Although the administration of nonsteroidal anti-inflammatory drugs (NSAIDs) has been reported to be effective for prophylaxis of HO after hip arthroplasty, there is currently no definitive prophylactic method following elbow trauma. Resection is considered a treatment for elbow HO, and the elbow's range of motion is surprisingly improved, but elbow function is not restored to its initial state:

●In one retrospective review of 42 traumatic elbow joints with HO, the average improvement in range of motion was 49 degrees with a recurrence rate of 13 percent [73].

●In 46 cases of elbows with either ankyloses or restricted range of motion because of HO, the average improvement was 96 degrees in the ankyloses group and 59 degrees in the HO group [74].

●In a systematic review of 626 elbows from 33 studies, the arc of motion was improved by 67 degrees with a relapse rate of 20 percent [75].

●In a trial comparing indomethacin with placebo in 164 patients following elbow injury, there was no significant difference in the incidence of heterotopic ossification (49 versus 55 percent, respectively) [76]. There was also no difference in patient-reported outcomes or the incidence of complications.

As described above, NSAIDs have not been definitively shown to prevent elbow joint HO, but they are reported to be effective as a secondary method of prevention after resection [77]. Radiation is also used as a secondary method, effectively reducing the recurrence rate of HO after the initial resection [78]. Some surgeons consider etidronate disodium as a potent agent for prevention, but its effectiveness remains questionable, and routine administration of it is highly discouraged [79].

AMPUTATION AND FUNCTIONAL OUTCOMES — Outcome studies have reported recovery patterns and the social effects of traumatic upper extremity injuries. Functional outcomes for severe upper extremity injuries are not significantly different in patients who have undergone limb salvage compared with amputation, although most patients prefer limb salvage initially. Long-term function depends more on patient social factors than upon the severity of the injury. Mortality for civilian extremity injury ranges from 5 to 10 percent.

Minor upper extremity injuries tend to reinstate proper function [80], but more extensive injuries including damage to the nerve or major arteries, blunt injuries, and proximal injuries are associated with poor functional outcomes and higher incidence of major and minor amputations [81-85].

The overall cost of treatment caused by temporary disability is estimated to be higher for upper extremity traumas, making it a larger economic burden compared with traumas involving the lower extremity [81,86]. The reason for this may relate to the greater proportion of patients with upper extremity injuries coming from the working population. Receiving workers' compensation tends to contribute to an increased health care cost and a longer time spent out of work compared with cases without it [87,88]. Appropriate proactive interventions to promote early active mobilization for the purpose of shortening this convalescent period may reduce the economic impact associated with upper extremity trauma within the labor force [81].

SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Extremity compartment syndrome" and "Society guideline links: Acute extremity ischemia" and "Society guideline links: Severe blunt or penetrating extremity trauma".)

SUMMARY AND RECOMMENDATIONS

●Damage control surgery – Damage control techniques are used to manage upper extremity injury in patients with concomitant life-threatening torso or head injuries. Damage control torso surgery takes priority over the extremity injury as long as sites of extremity bleeding remain controlled. Upper extremity fractures are managed with splinting, or external fixation; vascular injuries are managed with shunting of larger injured vessels or ligation of smaller vessels; injured nerves are rapidly identified and tagged if time permits; and soft tissues are irrigated and debrided to remove gross contamination, foreign material, and devitalized soft tissues. (See 'Damage control surgery' above.)

●Management of upper extremity injury – Limb salvage is aggressively pursued in the upper extremities. Achieving an optimal outcome in patients with severe upper extremity injuries requires a multidisciplinary approach with oversight by the general or trauma surgeon and commitment from other specialist surgeons. Definitive treatment includes internal fixation, arterial and venous reconstruction with autologous vein interposition graft(s), decompression or repair of peripheral nerves, and immediate or interval coverage of soft tissues. (See 'Fracture management' above and 'Revascularization' above and 'Wound coverage and reconstruction' above.)

●Postoperative care – The postoperative course for patients with upper extremity injury is highly variable depending on the nature and severity of extremity injury, associated injuries, and the patient's comorbidities. Patients should receive prophylaxis for venous thromboembolism as soon as is feasible. (See 'Postoperative care and follow-up' above.)

●Complications – Complications from severe upper extremity injury are common and can be life- or limb-threatening, and, thus, early recognition and treatment are important to minimize morbidity and mortality. Complications include wound complications (wound breakdown, surgical site infection), venous thromboembolism, rhabdomyolysis and myoglobinuria (crush injury, ischemia-reperfusion, extremity compartment syndrome), and heterotopic ossification. The threshold for performing extremity fasciotomy is low in patients with severe extremity injury. (See 'Complications' above.)

●Functional outcomes – Functional outcomes for severe upper extremity injuries are not significantly different in patients who have undergone limb salvage compared with amputation, although most patients prefer limb salvage initially. Long-term functionality depends more on patient social factors than upon the severity of the injury. Mortality for civilian extremity injury ranges from 5 to 10 percent. (See 'Amputation and functional outcomes' above.)

ACKNOWLEDGMENT — The UpToDate editorial staff acknowledges You Jeong Kim, BS, who contributed to an earlier version of this topic review.