Anatomic study of the volar surface of the distal radius (915.3)

Purpose: Analyze the anatomy of the the volar surface of the distal radius.Methods: We have studied 54 radiuses with Contour Gauge (General®, nº 337, USA) the volar surface of the radius in three planes: a)longitudinal, medium point of the volar surface of the distal radius; b)transversal, medial surface, perpendicular to the radius’ long axis and c)parallel to the joint, distant 5 mm from it. We have measured the inclination of distal radius on the volar and lateral planes,the morphology of the volar surface through the angle between the diaphysis and the watershed line(a);distance between the beginning of the protuberance and the watershed line(A);distance between the watershed line and the joint(B);distance from the protuberance beginning to the joint(C) and the height of volar portion(D). We have classified the contours into four types: Type I‐plain, with sudden inclination in the radial half; Type II ‐concave; Type III‐convex and Type IV‐plain.Results: The inclination angle (a) varied from 12o to 26o, average 19.81o ± 3.40º. The A value varied from 11.53mm to 33.12mm, average 19.54mm ± 4.98mm; the B value varied from 3.02mm to 7.40mm, average 4.74mm ± 0.85mm; the C value varied from 16.29mm to 39.19mm, average 24.29mm ± 5.13mm; and the D value varied from 4.42mm to 9.21mm, average 6.75mm ± 1.05mm. The contours classification in the long radius axis perpendicular plane were: 11 Type I, 17 Type II, 14 Type III and 12 Type IV. Parallel to the joint, 19 were Type I, 12 Type II, 11 Type III and 12 Type IV.Conclusion: The morphology of the radius volar surface was variable, and the study helped in the comprehension of the anatomy.