Mega Prosthetic Replacement of Elbow for Resistant Nonunion of Distal Humerus.

INTRODUCTION: Fractures of the distal humerus are a rare entity accounting for approximately 2% of the humeral fractures. Non union of the distal humerus is further rare and poses a major challenge. These fractures usually respond to open reduction and bone grafting but some may fail multiple surgical attempts at union and hence are labelled as "resistant" non union. We report a case of resistant non union of the distal humerus which was managed by total elbow arthroplasty.

CASE PRESENTATION: A 49-year-old male presented to the out patient department with history of a compound comminuted fracture of the distal end of the humerus approximately 25 years back. The fracture was treated with multiple debridements and plaster cast application. There was involvement of the radial and the ulnar nerves as well. The patient continued to use the disabled upper limb with severe difficulties in activities of daily living (ADL). The patient finally presented to us for regaining some range of motion and improvement in his ADL. In view of the grossly distorted anatomy, bone loss and chronic nature of the problem, patient was offered total elbow arthroplasty. The Wadsworth extensile posterior approach was used for exposure of the non union site. The fragments were found to be small, osteoporotic and deformed. In view of the distorted anatomy, the elbow was finally salvaged with mega-prosthetic replacement of the elbow. Posterior elbow splint was used for 2 weeks and active as well as passive range of motion was started after that. The post-operative Mayo elbow score improved from 50 to 80 and the patient was able to achieve a range of motion from 10 degrees to 110 degrees.

CONCLUSION: Total elbow arthroplasty can be used as a salvage procedure for resistant non union of the elbow with failed multiple failed attempts at union. It can also be used as a definitive procedure for severely distorted non union with massive bone loss with satisfactory functional results.