[Internal screwed plate for recent fractures of the humeral diaphysis in adults].

PURPOSE OF THE STUDY: Can medial plating of the humerus, through an antero lateral approach, diminish incidence of iatrogenic radial palsies?

MATERIAL AND METHODS: We carried out a prospective study of medial plating of humeral shaft fractures through an antero lateral approach between 1988 and 1997. 41 fractures were fixed, 36 were followed up for a mean period of 5.8 years. The indications were multiple injuries (10), displaced fractures (23), and failure of conservative treatment (3). Road traffic accidents and sports injuries were the cause in 68 per cent of cases. Two fractures were open and in 9 cases there was a radial palsy. Bone graft was never used. The approach to the medial aspect of the humerus an antero lateral incision was the essential feature of the technique. After a slightly curved incision on the antero lateral aspect of the arm, the space between biceps and brachialis anterior was bluntly dissected. The assistant holded the elbow flexed in order to relax the biceps and rotated il laterally to expose the medial aspect of the bone. Splitting brachialis fibres longitudinally exposed the fracture site. It was easy to check if the radial nerve was trapped and, if not, the nerve seen during the operation. Postoperatively patients were given a simple sling and mobilised freely, including rotation.

RESULTS: We had no intra-operative complications, no infections, no fixation failure, no post operative radial palsies and no non-unions. Results were excellent in 89 per cent of cases (full recovery of pain free range of movement). Four patient had a restriction of elbow movements of 10 degrees but without any discomfort. The mean time to union was 80 days. All radial nerve palsies recovered between 24 hours and 1 year. The plate was removed in 11 cases. Iatrogenic complications of humeral plating have led to the increased popularity of intramedullary nailing. Even if secondary radial palsies and non-unions have decreased, union of the humeral shafts is often difficult. Placing the plate into the medial surface allowed to preserve the radial nerve, but still permitted to check its continuity when it was trapped in the fracture site.

CONCLUSION: Restoration of the length and rotational alignment of the humerus puts the radial nerve in the best condition for its recovery. An antero lateral approach and a medially placed plate allowed to avoid secondary radial plasies and non-unions, which can complicate internal fixation of the humeral shaft.