Medial elbow exposure for coronoid fractures: FCU-split versus over-the-top

The optimal exposure interval for anteromedial coronoid fractures is unknown. The purpose of this study was to quantitatively compare the osseous and ligamentous exposure of the medial elbow using the flexor carpi ulnaris (FCU)-Splitting and Hotchkiss Over-the-Top approaches.

Forty surgical approaches were performed on 20 fresh-frozen cadaveric elbows using a randomized crossover design. Access to key anatomic landmarks [anteromedial facet, coronoid tip, sublime tubercle/anterior bundle of the medial collateral ligament (MCL), posterior bundle of the MCL, and radial head] was assessed. A calibrated digital image was taken from the surgeon's perspective of each approach, and these images were analyzed using a software program, ImageJ (NIH), to calculate the surface area of osseous structures exposed.

The average surface area exposed was 3 times greater with the FCU-Splitting approach (13.3 cm) compared with the Hotchkiss Over-the-Top approach (4.4 cm) (P < 0.0001). All key anatomic landmarks were directly visualized with the FCU-Splitting approach in each specimen. Visualization of the sublime tubercle/anterior bundle of the MCL and posterior bundle of the MCL was unobtainable with the Hotchkiss approach in 17 (85%) and 20 (100%) specimens, respectively. There were no statistically significant correlations between exposure and sequence of dissection, specimen age, gender, or laterality.

The FCU-Splitting approach provides more extensive exposure of the anteromedial coronoid and proximal ulna and the medial ligamentous structures than the Hotchkiss Over-the-Top approach.