Fractures of the Capitellum and Trochlea

The authors performed a retrospective study to evaluate the functional and radiographic outcome of patients with capitellum and trochlea fractures after open reduction and internal fixation.  From a database of fractures, 30 patients (over a span of 28 years) were identified as having undergone ORIF for an AO type B fracture of the distal humerus.  Outcomes for 23 patients at early follow-up (minimum 12 months) were determined based on review of medical records.  Fourteen patients returned for long-term evaluation (median time 17 years). 

Comparison of early and late results show a small increase in the median arc of elbow flexion from 106° (range 70° to 140°) to 125° (range 70° to 160°).  There was no significant difference in forearm rotation or in functional score (Broberg and Morrey) between the late and early groups.  There was a significant difference in outcomes (both at early and late evaluation) between categories of fractures as patients with more complex fractures had worse outcomes.

This study and a review of the literature indicate that what may appear to be an isolated capitellar fracture is often more complex and may involve substantial portions of the trochlea and lateral column.  This complexity is being identified more frequently with the widespread use of CT scans preoperatively.  The study is hampered by the small numbers and the functional results may be skewed by the fact that the majority of the patients available for long term follow-up were young at the time of injury (median age 35 years).  The follow-up data suggests that the functional results of ORIF for distal humeral shear fractures are durable over time.