Failed Fixation of Radial Head Fractures
摘要
Radial head fractures are prone to fixation failure in the setting of comminution combined with elbow or forearm instability. Detailed clinical, imaging, and laboratory assessment of the patient is necessary to determine the reasons for fixation failure and help devise a management plan, based on specific characteristics of the injury and the patient. Block to motion caused by intra-articular penetration of screws or plate malpositioning (without elbow or forearm instability) is treated by removal or revision of the implants if the fracture is healed. Block to motion caused by displacement of the radial head fracture after fixation failure (without elbow or forearm instability) is treated by radial head resection in most cases or by revised fixation in younger patients with a simple fracture and a radial head fragment of adequate size to allow for stable fixation. Revised fixation requires grafting of any defects and stable fixation with a plate placed in the safe zone to avoid impingement. In the setting of elbow or forearm instability, failed fixation of the radial head requires prosthetic replacement. In this setting, the radial head becomes critically important for stability of the elbow or forearm and after failed fixation, it would be extremely challenging to achieve stable fixation with revision osteosynthesis. The surgeon should be aware that the best course of action may only become apparent during surgery and should always be prepared to replace the radial head. Moreover, the surgeon should be ready to address any associated injuries and any residual elbow instability. Avoidance of excessive diameter and height of the radial head prosthesis is essential and is based on inspection and fluoroscopic evaluation of the elbow and the radial head prosthesis. In Essex-Lopresti injuries, fluoroscopic evaluation of the wrist is also required to verify restoration of ulnar variance.