This classification occasionally used in patients with intracapsular hip fractures is the Singh index.
- based on the degree of osteoporosis by fitting the pattern of proximal femoral trabecular lines into six separate categories.
- It shows poor interobserver and intraobserver levels of agreement.
-It does not correlate with bone mineral density as measured by DEXA scans.
- It is of little practical value in modern orthopaedic clinical practice.
FIGURE : Singh Index grades osteopenia from normal
(grade 6; all trabecular groups are visible) to definite (grade 3; thinned trabeculae with a break in the principal tensile group) to severe (grade 1; only the primary compressive trabeculae are visible, and they are reduced) based on the ordered reduction in trochanteric, tensile, and ultimately primary compressive trabeculae. The grade is determined from a true AP projection of an intact proximal femur. (Adapted from Singh M, Nagrath AR, Maini PS. Changes in trabecular pattern of the upper end of the femur as an index of osteoporosis. J Bone Joint Surg 1970;52A:457-467.)
ref: Rockwood & Green Adult Fractures.