Background: The aim of this study was to compare the complete visible surface area of the radial head, neck, and coronoid in the Kaplan and Kocher approaches to the lateral elbow. The hypothesis was that the Kaplan approach would afford greater visibility due to the differential anatomy of the intermuscular planes.
Methods: Ten cadavers were dissected with the Kaplan and Kocher approaches, and the visible surface area was measured in situ using a 3-dimensional digitizer. Six measurements were taken for each approach by 2 surgeons, and the mean of these measurements were analyzed.
Results: The mean surface area visible with the lateral collateral ligament (LCL) preserved in the Kaplan approach was 616.6 mm2 in comparison with the surface area of 136.2 mm2 visible in the Kocher approach when the LCL was preserved. Using a 2-way analysis of variance, the difference between these 2 approaches was statistically significant. When the LCL complex was incised in the Kocher approach, the average visible surface area of the Kocher approach was 456.1 mm2 and was statistically less than the Kaplan approach. The average surface area of the coronoid visible using a proximally extended Kaplan approach was 197.8 mm2.
Conclusions: The Kaplan approach affords significantly greater visible surface area of the proximal radius than the Kocher approach.
Keywords: Kaplan approach; Kocher approach; coronoid; elbow; posterior interosseous nerve; radial head.