Is the femoral neck-shaft angle an independent risk factor for hip fractures? An observational study


  • Bernard O. Obande Department of Orthopaedic Surgery, Federal Medical Center, Makurdi, Benue State, Nigeria
  • Emmanuel C. Iyidobi Department of Orthopaedics and Trauma, National Orthopaedic Hospital, Enugu State, Nigeria
  • Gabriel O. Eyichukwu Department of Orthopaedics and Trauma, National Orthopaedic Hospital, Enugu State, Nigeria
  • Cajetan U. Nwadinigwe Department of Orthopaedics and Trauma, National Orthopaedic Hospital, Enugu State, Nigeria
  • Remigus T. Ekwunife Department of Orthopaedics and Trauma, National Orthopaedic Hospital, Enugu State, Nigeria
  • Osita Ede Department of Orthopaedics and Trauma, National Orthopaedic Hospital, Enugu State, Nigeria



Femur, Neck-shaft angle, Hip, Fractures


Background: The femoral neck-shaft angle (FNSA) has been implicated in the aetiology of hip fractures. The longer moment arm of a higher FNSA has been theorized to impart a greater deforming force to the greater trochanter, which may cause a hip fracture.

Methods: A prospective study that involves adults with hip fractures and a control group matched for age and sex. The FNSA of both groups were measured on an anteroposterior X-ray of the pelvis. The mean FNSA were compared with a paired samples t-test, and a binary logistic regression analysis was run with the FNSA as a predictor variable and the presence of hip fracture as an outcome variable.

Results: A total of 150 patients were recruited for the study, 75 per group. The mean age of patients with hip fractures was 71.30 years (S.D.=14.34), and that of the control group was 73.94 years (S.D.=12.55), p=0.264. The mean FNSA of the study group was 133.96o (S.D.=3.77) while that of the control group was 131.05o (S.D.=3.86), p<0.001. Increasing FNSA imparts a higher risk of having a hip fracture, O.R.=1.24 (95% C.I, 1.12-1.37).

Conclusions: Individuals with higher FNSA demonstrated a significantly increased risk of developing hip fractures. However, the exact cut-off point of the FNSA, which predisposes to the risk of these fractures, remains to be elucidated. 


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Original Research Articles