Humerus Fracture with Radial Nerve Palsy and Wrist Drop – Diagnosis and Treatment скачать в хорошем качестве

Humerus Fracture with Radial Nerve Palsy and Wrist Drop – Diagnosis and Treatment

Join this channel to support the channel:    / @nabilebraheim  . Fracture of the humerus with associated radial nerve palsy. The radial nerve can be identified as it courses through the spiral groove between the heads of the triceps. The nerve lies posterior to the deltoid tuberosity. It crosses the posterior aspect of the humerus, approximately 20 centimeters proximal to the medial epicondyle and about 15 centimeters proximal to the lateral epicondyle. When a fracture occurs, the anatomy becomes distorted, making these landmarks less reliable. In such cases, the radial nerve can be located approximately 4 centimeters, or two finger breadths, proximal to the point of confluence of the triceps aponeurosis with the long and lateral heads of the triceps. The radial nerve enters the anterior compartment of the arm approximately 10 centimeters proximal to the elbow joint. Radial nerve palsy occurs in about 8% to 15% of patients with humeral shaft fractures, most commonly in the form of neuropraxia. Radial nerve function should always be examined. In the Holstein–Lewis fracture, a spiral fracture of the distal third of the humerus, the incidence of radial nerve neuropraxia increases to approximately 22%. Radial nerve function must be assessed before and after fracture reduction, with particular attention to wrist and finger extension. Primary radial nerve palsy usually results directly from the injury, with increased frequency in distal third Holstein–Lewis fractures and in mid-shaft transverse fractures. In closed fractures, radial nerve injury is most often neuropraxia and tends to improve with time. In contrast, open fractures raise concern for radial nerve laceration or neurotmesis. Open fractures have a higher incidence of partial or complete laceration of the radial nerve, and therefore surgical exploration should be considered. For closed fractures with complete radial nerve palsy, treatment generally consists of immobilization with a coaptation splint followed by a functional brace and observation for return of function. Approximately 85% of patients demonstrate improvement within three to four months, with complete recovery at around six months. In open fractures, there is an absolute indication for radial nerve exploration, with nerve repair, delayed nerve grafting, or tendon transfer considered as needed. If an open fracture is associated with radial nerve palsy, incision and debridement of the wound should be performed, the radial nerve explored, and the fracture stabilized. Patients with radial nerve palsy typically present with weakness of wrist and finger extension. It is essential to confirm that the patient is extending the metacarpophalangeal joints rather than the interphalangeal joints, as interphalangeal extension is a function of the intrinsic hand muscles supplied by the ulnar nerve and not by the radial nerve. If there is uncertainty, asking the patient to perform the hitchhiking sign (thumb extension) provides a more reliable test. When assessing recovery of wrist extension, the test should first be performed with gravity eliminated, which corresponds to a grade of 2 out of 5. Recovery against gravity represents 3 out of 5 strength. This is the appropriate method to evaluate wrist extension recovery. Monitoring for nerve recovery includes fracture immobilization, wrist splinting, and electrodiagnostic studies performed at around six weeks. Fibrillation potentials are a poor prognostic sign, while polyphasic potentials indicate recovery. The brachioradialis is the first muscle to demonstrate re-innervation, while the extensor indicis is the last. Measuring the distance from the fracture site to the brachioradialis may help estimate the expected time to recovery, as axonal regeneration occurs at a rate of approximately one millimeter per day. Wrist extension with radial deviation returns first because the extensor carpi radialis longus and brevis are innervated earlier than the extensor carpi ulnaris. If there is no clinical or electromyographic evidence of recovery within four to six months, tendon transfer may be indicated. For restoration of wrist extension, the pronator teres can be transferred to the extensor carpi radialis brevis. For finger extension, the flexor digitorum superficialis, flexor carpi ulnaris, or flexor carpi radialis may be transferred to the extensor digitorum communis. For thumb extension, either the palmaris longus or the flexor digitorum superficialis may be transferred to the extensor pollicis longus. In low-velocity gunshot fractures of the humerus, treatment typically involves a coaptation splint, even in the presence of radial nerve palsy. Iatrogenic radial nerve palsy may occur with surgical approaches. The incidence is approximately 20% with the lateral approach, 10% with the posterior approach, and 5% with the anterolateral approach, where the nerve lies between the brachialis and brachioradialis muscles. .