«Orientación de la ranura bicipital: Consideraciones para la retroversión de la prótesis en fracturas del húmero proximal.»
Frédéric Balg MD, FRCSC, Martin Boulianne MD, FRCSC and Pascal Boileau MD,
Department of Orthopaedic Surgery, Hôpital de lArchetUniversity of Nice, Nice, France
The bicipital groove anatomy is well documented, and this groove is used as a landmark to guide retroversion during implantation of a shoulder prosthesis. Whereas the proximal part of the groove is used in osteoarthritis, the distal part is used in fractures. If used in 4-part fracture cases, we must assume that the bicipital groove orientation is constant from proximal to distal. We measured the groove orientation in 40 cadaveric humeri using 3 superimposed computed tomography sections. The reference axis was the transepicondylar axis at the elbow level. The measured angle of the bicipital groove was 55.8° ± 4.5° at the anatomic neck and 65.1° ± 3.5° at the surgical neck. This difference (mean of 9.3°, with extremes of −3° and 22.5°) was statistically significant. We confirmed a wide range of variation from 22° to 89° in the orientation of the groove. Because the values listed in the literature for lateral fin placement of a prosthesis have not been measured at the surgical neck level and because of the great variation in groove orientation, we caution surgeons about the use of the bicipital groove as a reliable landmark in shoulder replacement for fractures. Considering the risk of over- or under-retroversion of the prosthesis, we recommend the use of a fracture jig with retroversion set to 20°.
Journal of Shoulder and Elbow Surgery Volume 15, Issue 2 , March-April 2006, Pages 195-198.