Surgery

Upper extremity surgery can improve hand function in a few selected cases. The ideal surgical candidate must be a motivated, intelligent child who has good sensation in the handand uses the extremity. Those children with satisfactory handeye coordination can benefit from surgery even when hand sensation is poor.

The surgeon must be careful in patient selection because some children develop adaptive mechanisms to compensate for lost hand movements as they grow. Functional loss occurs after surgery in such patients because surgery prevents the adaptive movements they developed over the years. Consider surgery between 6- 12 years of age when the child will cooperate with postoperative rehabilitation. Set goals that fit with the expectations of the child and the parents.

Before surgery should be considered the followings

• Voluntary hand use
• Sensation
• Intelligence
• Athetosis

The shoulder Adduction – internal rotation contracture is the most common problem. Provide a program of stretching exercises. Consider surgical lengthening of the muscles if the deformity is severe.

The elbow Flexion contractures of more than 45 are functionally disabling. Try botulinum toxin injection to elbow flexors and stretching exercises in dynamic deformities and even for cosmetic reasons. Consider surgery for elbow only if the hand is functional, if there is skin breakdown at the elbow or if hygiene in the antecubital fossa is poor. Deformities greater than 60o require surgical lengthening of the biceps tendon, be aware of the fact that this procedure worsens the forearm pronation deformity. Maximum range of motion is gained 3 months postoperatively.

Forearm The main problem is a pronation contracture because of spasticity in the pronator teres and pronator quadratus muscles [B]. Activities that require supination like grasping a walker or a cane, balancing objects in the palm, washing the face are impossible. Severe pronation causes radial head dislocation but it is generally painless and does not cause functional problems. Consider pronator teres transfer to the supinator if the child can voluntarily pronate the forearm. Pronator release gives satisfactory results if the child has active supination. Longstanding pronation contracture of the forearm leads to relative shortening of the biceps aponeurosis. Release this structure to allow the biceps to be a more effective supinator.

Wrist The wrist usually is held in a position of flexion and ulnar deviation because of flexor carpi radialis and flexor carpi ulnaris spasticity [D, E]. The digital flexors also contribute to wrist flexion. Finger flexors are inefficient and the grasp is weak when the wrist is flexed [F]. Grasping is essential for function. Correct flexion contractures of wrist and fingers and adduction of thumb if they interfere with grasp. Macerations and mycotic infections are common in severe flexion contractures of the hand. Surgery becomes necessary for hygienic purposes. Options for surgery [G] include wrist flexor lengthening, flexor origin slide, tendon transfer to improve wrist extension, proximal row carpectomy, and wrist fusion with or without carpal shortening [H]. Avoid wrist arthrodesis because the patient loses the tenodesis effect of wrist extension that results in finger flexion and facilitates grasp and release. Consider wrist arthrodesis only to relieve the pain and improve the cosmesis of the hand when there is no or limited hand function. Wrist and digital flexor muscles can be selectively lengtheneddistally. Do not release or transfer both flexor carpi ulnaris and radialis as this eliminates active wrist flexion.Consider tendon transfers to augment wrist extension when it is weak or absent. Transfer the flexor carpi ulnaris to extensor digitorum communis when both finger and wrist extension is weak. This transfer improves wrist extension and does not impair finger extension and release.

Fingers Finger flexion deformity is a result of spasticity and contracture in the flexor digitorum superficialis and profundus muscles [1]. It becomes more obvious when the wrist and metacarpophalangeal joints are held in neutral position. Consider surgical intervention when flexion deformity is severe [2]. The flexor-pronator origin release effectively lengthens the flexor digitorum superficialis, pronator teres and flexor carpi radialis. Correct finger flexion deformity by direct Z-lengthening of involved tendons. If there is spasticity of intrinsic hand muscles, releasing the finger flexors will increase the deformity. Excessive lengthening weakens flexor power, impairs grasp, and can produce swan neck deformities. In this case, transfer the flexor digitorum superficialis tendon to augment wrist, finger or thumb extension instead of lengthening. Swan-neck deformity [3] is hyperextension deformity of the proximal interphalangeal joints. It is because of over-activity of the intrinsic muscles, and increases with the pull of the extensor digitorum communis when the wrist is in flexion. Consider surgical intervention if there is severe hyperextension, or when the proximal interphalangeal joints lock in extension. The thumb The thumb-in-palm deformity [4] is characterized by metacarpal flexion and adduction, metacarpophalangeal joint flexion or hyperextension and usually interphalangeal joint flexion. The causes are spasticity and contracture of the adductor pollicis, first dorsal interosseous, flexor pollicis brevis, and flexor pollicis longus . The extensor pollicis longus, extensor pollicis brevis, and/or abductor pollicis longus are often weak or ineffective. The thumb-in-palm deformity impairs the ability of the hand to accept, grasp, and release objects. The goals of surgery  are to release the spastic muscles to position the thumb, to create a balance in the muscles around the thumb, and to provide articular stability for grasp and pinch.