Shoulder and Elbow Surgery: Shear fractures of the capitellum.

This case demonstrates a rare injury to the elbow. Shear fractures of the capitellum can be communicated like in this case. Comminution can make treatment difficult. This is a retired woman in her 50s who fell on the left elbow. She has as seen on plain radiographs and 3D reconstruction a comminuted fracture of the capitellum and anterior subluxation of the radial head. Operative fixation requires preservation of the LCL and a LCL sparing lateral approach.

Tips:

1. Kocher LCL sparing lateral approach to the elbow with the incision on the skin 2cm anteriorly compared to the classic approach

2. Preservation of the LCL. Develop interval between anconeus and ECRB/ECRL. Avoid excessive retraction anteriorly over common extensor mass that can damage the radial nerve.

3. Excision of bone fragments that are too small to be fixed. Visualization of the trochlear - capitellum area to avoid medial step-off at the articular surface

4. Anterior to posterior headless screws have better chances of healing of the fracture compared to posterior to anterior. Vascularity of distal humerus is rich and comes from the posterior aspect of the elbow

5. Disadvantage of AP screws is that in case of AVN or non union the screws can became prominent and lead to DJD of the radial head and elbow.

A similar case of a capitellum shear fracture with free fragments in the joint is demonstrated below. Removal of free fragments was performed and the largest fracture was fixed with "minimal drilling" using a threaded K wire to avoid pin migration and a headless compression screw. The patient had a preoperative QuickDASH score of 79 and postoperative QuickDASH score of 0 (0 means no limitation in function). The patient was pain free with full ROM to the elbow at 6 months postoperatively.