Volkmanns ischemic contracture

Volkmann's ischemic contracture was first described by Volkmann in 1881 [17]. The contracture follows a supracondylar fracture in which there has been circulatory embarrassment. This has led to a compartment syndrome that has progressed to the classic picture of Volkmann's ische-mic contracture. The end result is a pronated forearm, a flexed wrist, an adducted thumb, and the metacarpal phalangeal joints extended. The interphalangeal joints of the fingers and thumb are in a flexed position (Fig. 1). Most cases of Volkmann's ischemic contracture could have been prevented by appropriate management of the supracondylar fracture initially or by early recognition and treatment of any developing compartment syndrome. Once established, however, a full recovery is impossible. In severe cases, functioning free muscle transfers can be helpful in providing active finger flexion; however, normality can never be restored. Thus, prevention and avoidance of this devastating complication should be emphasized. Closed reduction of supracondy-lar fractures under fluoroscopic control and insertion of percutaneous Kirschner wires facilitate the reduction and allow the elbow to be placed into

Fig. 1. Classic picture of Volkmann's ischemic contracture.

extension. This minimizes the chance of reducing arterial flow in the brachial artery, which may go on to cause swelling and lead to a compartment syndrome with subsequent Volkmann's ischemia. This ischemic process then progresses to myonec-rosis, and, if unrelieved, irreversible muscle death occurs. If a fasciotomy is not undertaken at this point, the ischemic muscle dies, becomes tighter, and shortens, leading to Volkmann's ischemic contracture.

Most cases of Volkmann's ischemic contracture are severe, and there is virtually no muscle function and a significant nerve deficit as well. Volkmann's ischemic contracture has been classified by Lipscomb [18] into four categories according to its severity. Grade I is mild with good muscle function and no nerve involvement. Grade II is considered moderate; it has considerable loss of muscle function yet no nerve deficit. Grade III has severe muscle loss and often some nerve deficit. Finally, grade IV is severe with no residual muscle function and also significant nerve deficit. It is thought that many cases in the grade I category go unrecognized, and many cases in the grade II category do not require reconstruction because they function well. Most surgical interventions are performed in grade III or grade IV categories and optimally involve functioning free muscle transfer.

Management of established Volkmann's ischemic contracture

The goal in the management of an established Volkmann's ischemic contracture is to restore as much function to the extremity as possible. A detailed evaluation of the patient and the involved extremity is undertaken. A plan can then be formulated to reconstruct the injured tissues and rebuild the damaged extremity.

Clinical assessment

First, a detailed history is obtained, with a clear picture of any previous surgical procedures. Particular attention should be paid to any surgical debridement. Unfortunately, when the tissues are necrotic, it is difficult to distinguish the involved nerves, and these have sometimes been mistakenly debrided. A detailed history outlining the functional impairment as perceived by the patient and his or her family is then undertaken, followed by a detailed physical examination. The physical examination must include all structures in the forearm and hand, ranging from the circulatory system to the assessment of nerves, muscles, joints, and soft tissues. The arterial inflow should be assessed by brachial, radial, and ulnar pulses as well as by angiography. The arterial inflow into the forearm should be as powerful as possible. This may require vascular reconstruction before the muscle transfer. The angiogram can also provide valuable information about the anterior interosseous vessels. These are the key vessels involved in muscle transplantation and, importantly, lay beside the key nerve that is going to innervate the muscle, namely, the anterior inter-osseous nerve. Thus, the angiogram can not only assess the continuity of the brachial, ulnar, and radial arterial systems (Fig. 2) but provide valuable information about any damage that has been done to the anterior interosseous nerve. If the angiogram shows a healthy pristine anterior interosseous artery, one can assume that the anterior interosseous nerve, which lies adjacent to it, is

also uninjured. The vessels are used as the recipient vessels in a muscle transplant procedure, and the nerve is used as the motor nerve to innervate the transplant.

Assessment of the major nerves to the forearm should also be performed. Clinical examination of the median, ulnar, and radial nerves may be aided by electromyographic (EMG) and nerve conduction studies. Often, diminished nerve function is related to an ischemic process that has involved the nerves similar to the process of myoneural necrosis. When the nerve is heavily encased in scar, it is sometimes helpful to release that scar in the form of a neurolysis to provide additional motor and sensory function in the distal component of the extremity. When there is no median or ulnar nerve function, one must suspect a physical defect in the nerve and consider reconstruction. Motor nerve function can also be evaluated by electromyography of the pronator quadratus muscle. Because this muscle lies distal in the volar forearm, if its function can be confirmed, it is likely that the anterior interosseous nerve is functional as well. Some degree of active EMG activity is indicative of a functioning anterior interosseous nerve even in the face of extensive muscle damage from the ischemic process. When uncertainty still persists regarding the function of a needed motor nerve, it may be wise to perform a nerve biopsy to confirm the usability of the nerve. This becomes particularly important when there is high upper arm or axilla injury as well.

It is probably best to carry out nerve reconstruction before any motor reconstruction with the aim of obtaining a sensate hand. Often, nerve grafting is needed to correct any significant nerve gap in an attempt to provide sensibility to the hand.

Evaluation of all muscle groups should be carefully undertaken. Even a flicker of motion is important to document. This often indicates that even though most of the muscle has become necrotic, the motor nerve to the muscle is still functioning. This can be crucial information when planning a muscle transfer procedure.

It is important to have adequate mobility of the wrist and fingers. This may be limited by the tightness of the contracture, and attempts should be made to improve the range of motion through rehabilitation. With tight tendons, it may only be possible to achieve partial joint mobility, but attempts should be made to improve this as much as possible. There is no point in trying to provide a new motor to a joint if the joint is stiff.

Thus, it may be necessary to release tight immobile joints surgically before any muscle reconstruction is undertaken. Tenolyses and cap-sulotomies may be necessary.

Extensive tightness may also occur in the volar soft tissues, and this should be fully evaluated as well. Soft tissue tightness may not only limit passive joint mobility but impinge on muscle contraction and tendon gliding. Thus, it may be necessary to provide adequate soft tissue cover and release any soft tissue tightness. This can be accomplished with a distant pedicle flap (Fig. 3) or a free tissue transfer.

In addition to evaluating the upper extremity in terms of its symptomatology and clinical findings, one must evaluate the child from a psychosocial standpoint. The child and family should be given realistic expectations regarding reconstruction and a detailed outline as to what is required after surgery. It is important to have a well-motivated patient. A rather complex and time-consuming rehabilitation program is needed to achieve the most gain from any reconstruction. Considerable rehabilitation is necessary; thus, the patient must be compliant, and the family must be prepared to work with the child in the postoperative rehabilitative phase. Otherwise, one achieves only minimal gain.

Preoperative physiotherapy is often helpful to gain as much mobility in the forearm and hand as possible. Emphasis should be placed on pronation and supination of the forearm. This is often a difficult problem to address after the muscle transplant. If mobility is not possible, the forearm should be positioned so as to be in the most functional semipronated position. Attempts should be made to improve forearm pronation

Fig. 3. Pedicle flap in preparation for muscle transplantation.

and supination. To do this, a tight pronator teres muscle may require release. In addition, the pro-nator quadratus in the distal forearm is often tight and limits supination. The next structure that can be involved is the interosseous membrane. This may require an incision to provide passive supination. Finally, the tight capsule around the head of the radius may need to be released. Even with these four procedures, the amount of active supination and pronation gained is often disappointing. Even a small amount of movement is worthwhile, however, and provides a baseline on which to build.

When the circulation has been optimized, the sensory input optimized, and the joint and soft tissues fully mobilized, the stage is set for providing additional active muscle function. Free functioning muscle transplantation to the forearm has revolutionized the care of childhood Volk-mann's ischemic contracture [19]. Although far from providing normal function, it can upgrade the usefulness of an extremity enormously.

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