Radiographic Anatomy of the Neck-Shaft Angle of Femur in Nepalese People: Correlation with its Clinical Implication

Background Neck-shaft angle (NSA) is one of the prominent features in the proximal femur which is an important determinant of fracture of femoral neck. Present study evaluating the value of neck-shaft angle has relied heavily on radiographs. As knowledge of neck-shaft angle is important to orthopaedic surgeons, there is need to elucidate whether there is significant variation of this angle among the two different genders and various age groups of both right and left femora of Nepalese population. Objective To ascertain the value of neck-shaft angle in the Nepalese population by means of a radiographic study and to correlate the values with regard to right neck-shaft angle/ left neck-shaft angle side (RNSA/LNSA), gender and three different age group. Method Normal pelvic radiographs of 148 patients seen at department of orthopedic and radiology, College of Medical Sciences- Teaching Hospital (COMS-TH), Bharatpur, Chitwan from the month of February 2017 to June 2017 were divided into two different gender and three different age groups (21-40 years, 41-60 years and Above 60 years) and their neck-shaft angle of both right and left sides were recorded. Result The average of RNSA and LNSA were found to be 132.96±6.05° and 131.54±13.66° respectively for male and 134±6.57° and 132.98±6.23° respectively for female. In total the average RNSA and LNSA were 133.51±6.32° and 132.26±10.61° respectively. Similarly, the average RNSA and LNSA for three different age groups (21-40 years, 41-60 years and Above 60 years) were found to be 133.76±6.44°, 133.69±6.36° and 132.50±6.06° and the 133.35±6.29°, 132.47±5.85° and 128.84±21.98° respectively. Conclusion The average neck-shaft angle recorded here shows no significant difference in both RNSA and LNSA in males except for a small and significant difference in LNSA in female of three different age groups.