Proximal radial drift following radial head resection.

BACKGROUND: Proximal radial migration is a well-documented phenomenon after radial head resection, but there have been no studies evaluating other planes of proximal radial stump drift after resection. The purpose of this study is to evaluate the anatomic position of the radial stump in relation to the capitellum after radial head resection, and determine the factors affecting this position and long-term functional outcomes.
METHODS: Thirteen patients who had undergone radial head resection for a variety of injury patterns were identified and evaluated at a mean of 72 months postoperative. Each patient underwent a physical exam and outcome questionnaire evaluation (Disabilities of the Arm, Shoulder, and Hand [DASH] questionnaire, Mayo Elbow Performance Score [MEPS], and pain Visual Analog Scales [VAS] questionnaire). Anterior-posterior (AP) and lateral radiographs of the elbow were also performed.
RESULTS: The proximal radius resection length was an average of 18 mm (range, 11.1-31.9) compared to the nonoperative side. The proximal radial stump was determined to have significant migration both medially (P = .01) and posteriorly (P = .002) as compared to the opposite side as determined on the AP and lateral radiographs, respectively. Greater than 2 cm of proximal radial resection was associated with greater posterior drift (P = .03). Poorer MEPS were only correlated with an initial dislocation injury pattern (P = .02).
CONCLUSION: Radial head resection for fracture often leads to posterior and medial drift of the proximal radial stump, resulting in nonanatomic alignment with the capitellum. Increased resection greater than 2 cm resulted in larger amounts of drifting. Only a dislocation injury pattern was associated with worse functional outcomes.