DOI: http://dx.doi.org/10.18203/issn.2455-4510.IntJResOrthop20194811

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

Bernard O. Obande, Emmanuel C. Iyidobi, Gabriel O. Eyichukwu, Cajetan U. Nwadinigwe, Remigus T. Ekwunife, Osita Ede

Abstract


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. 


Keywords


Femur, Neck-shaft angle, Hip, Fractures

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References


Kanis JA, Odén A, McCloskey AV, Johansson H, Wahl DA, Cooper C. A systematic review of hip fracture incidence and probability of fracture worldwide, International Osteoporosis Foundation and National Osteoporosis Foundation. Osteoporosis Int. 2012;23(9):2399-400.

Lareau C, Sawyer G. Hip Fracture Surgical Treatment and Rehabilitation. 2010. Available at: rimed.org/medhealthri/2010-04/2010-04-108.pdf. Accessed 25th June 2019.

Butler M, Forte M, Kane RL, Joglekar S, Duval SJ, Swiontkowski M, et al. Treatment of Common Hip Fractures. Evid Rep Technol Assess (Full Rep). 2009;184:1-85.

Johnell O, Kanis JA, Oden A, Johansson H, De Laet C, Delmas P, et al. Predictive value of BMD for Hip and other fractures. J Bone Miner Res. 2005;20(7):1185-94.

Patron MS, Duthie RA, Sutherland AG. Proximal femoral geometry and hip fractures, Acta Orthop Belg. 2006;72:51-4.

Jing G, Yia-Wei S, Xiao S. Mechanical analysis and computer simulation of the structure of femoral neck 2006. Available at: http://asbweb.org/ conferences/2006/pdfs/269.pdf. Accessed 25th June 2019.

Harva TC, Meriheryavuz MC. Comparison of femoral geometry among cases with and without hip fractures, Yonsei Med J. 2004;45(5):901-7.

Wang Q, Teo JW, Ghasem-Zadeh A, Seeman E. Women and men with hip fractures have a longer femoral neck moment arm and a greater impact load in a sideways fall. Osteoporos Int. 2009;20(7):1151-6.

Alonso CG, Curiel MD, Carranza FH, Cano RP, P´erez AD. Femoral bone mineral density, neck-shaft angle and mean femoral neck width as predictors of hip fracture in men and women. Multicenter Project for Research in Osteoporosis. Osteoporosis Int. 2000;11(8):714–20.

Ulusoy H, Bilqici A, Kuru O, Sarica N, Arslan S, Erkorkmaz U. A new value of proximal femoral geometry to evaluate hip fracture risk; true moment arm. Hip inter. 2008;18(2);101-7.

Ripamonti C, Lisi L, Aveila M. Femoral neck shaft angle width is associated with hip fracture risk in males but not independent of femoral neck bone density. Br J Radiol. 2014;87:1037.

Chummy SS. Last’s Anatomy: Regional and Applied. 12th Edition. UK, Elsevier Ltd; 2011: 170.

Solomon L, Warwick D, Nayagam S. Apley’s Systems of Orthopaedics and Fractures. 9th edition. United Kingdom, Hodder Arnold: Hachette UK company; 2010: 843-859.

Adekoya-Cole TO, Akinmokun OI, Soyebi KO, Oguche OE. Femoral neck shaft angles: A radiological anthropometry study. Niger Postgrad Med J. 2016;23:17-20.

Gilligan I, Chandraphak S, Mahakkanukrauh P. Femoral Neck-Shaft Angle in Humans: Variation Relating to Climate, Clothing, Lifestyle, Sex, Age and Side. J Anat. 2013;223(2):133-51.

Kaptoge S, Beck JT, Reeve J, Stone LK, Hillier AT, Cauley JA, et al. Prediction of Incident Hip Fracture Risk by Femur Geometry Variables Measured by Hip Structural Analysis in the Study of Osteoporotic Fractures. J Bone Miner Res. 2008;23:1892–904.

Filipov O. Femoral Neck Fractures – Biological Aspects and Risk Factors. J of IMAB. 2014;20(4):513-5.

Gnudi S, Sitta S, Pignotti E. Prediction of incidence of hip fracture by femoral neck bone mineral density and neck shaft angle- a 5-year longitudinal study in postmenopausal females. Br J Radiol. 2012;85:1016.

Tuck SP, Rawling DJ, Scane AC, Pande J, Summer P, Wolf N, et al. Femoral neck shaft angle in men with fragility fracture. J Osteoporosis. 2011;2011:903726.