Ward’s triangle (Singh et al. 1970, 1972, 1973) is an area with loose and thin trabeculae. This triangle be-comes prominent in osteoporosis. As osteoporosis worsens, the triangle opens up laterally. Based on this se-quence, Singh and coworkers (Singh et al. 1970, 1972) proposed an index which can be used as a scale for assessing the severity of osteoporosis (Fig. 7). The classification ranges from grade VI (normal with visualiza-tion of all the trabeculae) to grade I (loss of even the primary compressive trabeculae). Singh et al. later added grade VII in people with dense bones. However, recent studies have indicated poor correlation between Singh’s index and bone density assessed by bone mineral densitometry techniques (Hübsch et al. 1992; Koot et al. 1996; Salamat et al. 2010).
Singh's index: Categorization of femoral neck bone mineral density upon the visual scale of the trabecular bone existence on x-ray.
The Singh's categories include:
Grade 1: Thin principle compression trabeculae
Grade 2: Principle compression trabeculae
Grade 3: Thin principle tensile trabeculae, with discontinuity
Grade 4: Thin principle tensile trabeculae, with continuity
Grade 5: Thin principle tensile and compression trabeculae
Grade 6: Normal appearance
Reduced density of trabecular bone in the area, which is described by means of Singh's index (grades 3, 2, and 1), could reflect the diagnosis of osteoporosis
