A cadaveric study of radial and ulnar bowing in the sagittal and coronal planes

J Shoulder Elbow Surg. 2020 May;29(5):1010-1018. doi: 10.1016/j.jse.2019.10.016. Epub 2020 Mar 4.


Background: This study provides a comprehensive, full-length assessment of radial and ulnar bowing in anteroposterior (AP) and sagittal planes.

Methods: Radial and ulnar AP and lateral bowing were assessed using orthogonal digital photographs of 211 randomly selected cadaveric bilateral forearms (422 radius, 422 ulna bones) from a well-preserved osteologic collection.

Results: In the radial AP plane, an apex-radial bow was present at a mean of 58% of bone length (slightly distal to midpoint), with a mean depth of 1.3 cm. In the radial lateral plane, an apex-dorsal bow occurred at a mean of 45% of bone length, with a mean depth of 0.8 cm. In the ulnar AP plane, apex-radial bow occurred at a mean of 32% of bone length with a mean depth of 1.0 cm. In the ulnar lateral plane, the majority of specimens (81%) had an apex-dorsal bow, whereas 19% had a reverse (apex-volar) bow. Lateral ulnar bow was located at a mean of 33% of bone length with a mean depth of 2.0 cm, with 36% of specimens possessing a lateral bow located at 35% or more distal along the ulna. Side-to-side differences for bow location and depth were less than 2% of bone length.

Conclusions: Ulnar lateral bow was found to be more distal than in previously published works, which analyzed only the proximal ulna, and this study describes a reverse ulnar bow in 19% of specimens. This demonstrates lateral ulnar morphology to be more variable than previously defined with minimal side-to-side variability, which are important considerations for fracture fixation and elbow arthroplasty.

Keywords: Bowing; PUDA; angulation; forearm; osteology; radius; ulna.

MeSH terms

  • Adult
  • Anatomic Variation
  • Cadaver
  • Female
  • Humans
  • Male
  • Middle Aged
  • Radiography
  • Radius / anatomy & histology*
  • Radius / diagnostic imaging
  • Ulna / anatomy & histology*
  • Ulna / diagnostic imaging