In vitro biomechanical comparison of various implants in Pauwels type 3 fracture neck femur


  • Birju Manjhi Department of Orthopaedics (Trauma Centre), Institute of Medical Sciences, BHU, Varanasi, U. P., India
  • S. C. Goel Department of Orthopaedics, Heritage Institute of Medical Sciences, Varanasi, U. P., India
  • Abhijeet Kunwar Department of Orthopaedics (Trauma Centre), Institute of Medical Sciences, BHU, Varanasi, U. P., India
  • Vakil Singh Department of Metallurgical Engineering, IIT, BHU, Varanasi, U. P., India



Proximal femoral nail, Femoral neck fracture, Cadaveric model, Pauwels


Background: The objective of this study was to find out the correlation among type of implant, type of fracture and quality of bone in a cadaveric model of unstable fracture neck of femur (Pauwels type 3) fixed with either; proximal femoral nail (PFN), dynamic hip screw (DHS), dynamic hip screw with an anti-rotation screw (DHS and ARS) or cannulated cancellous screws (CCS).

Methods: This study was conducted on 24 cadaveric bones (6 in each group) in which unstable fracture neck of femur (Pauwels type 3) were created and fractures in each group were fixed with different implants after creating a comparable group using DEXA scan. These were tested on a cyclic physiological loading machine at 2 cycles per second with a load of 200kg. The test was observed for 10,000 loading cycles or till failure whichever occurred earlier. Subsidence was measured and analyzed.

Results: Five specimens in the PFN group, 3 specimens in the DHS and ARS and DHS group completed 10,000 cycles while all the specimens in CCS group failed before 10000 cycles. Mean subsidence of the PFN group was significantly lower than the other groups.

Conclusions: PFN constructs were stronger than the other constructs. However, these data must be interpreted as strictly biomechanical, representing only part of the scenario at work in vivo. Nonetheless, the significant findings of increased strength of fixation over the DHS, DHS with ARS and CCS certainly appear to support the use of PFN clinically.


Author Biographies

Birju Manjhi, Department of Orthopaedics (Trauma Centre), Institute of Medical Sciences, BHU, Varanasi, U. P., India

Assistant Professor, orthopaedics(trauma centre)

Abhijeet Kunwar, Department of Orthopaedics (Trauma Centre), Institute of Medical Sciences, BHU, Varanasi, U. P., India

Assistant Professor, orthopaedics(trauma centre)


Koval KJ, Zuckerman JD. Hip fractures I: Overview and evaluation and treatment of femoral neck fractures. J Am Acad Orthop Surg. 1994;2:141-9.

Askin SR, Bryan R. Femoral neck fractures in young adults. Clin Orthop Relat Res. 1976;114:259-64.

Dedrick DK, Mackenzie JR, Burney RE. Complications of femoral neck fracture in young adults. J Trauma. 1986;26:932-7.

Bayliss AP, Davison JK. Traumatic osteonecrosis of the femoral head following intracapsular fracture: incidence and earliest radiological features. Clin Radiol. 1977;28:407-14.

Gautam VK, Anand S, Dhaon BK. Management of displaced femoral neck fractures in young adults (a group at risk). Injury. 1998;29:215-8.

Banks HH. Nonunion in fractures of the femoral neck. Orthop Clin North Am. 1974;5:865-85.

Stankewich CJ, Chapman J, Muthusamy R, Quaid G, Schemitsch E. Relationship of mechanical factors to the strength of proximal femur fractures fixed with cancellous screws. J Orthop Trauma. 1996;10:248-57.

Bhandari M, Devereaux PJ, Tornetta P. Operative management of displaced femoral neck fractures in elderly patients: an international survey. J Bone Joint Surg Am. 2005;87:2122-30.

Bhandari M, Tornetta P, Hanson B, Swiontkowski MF. Optimal internal fixation for femoral neck fractures: multiple screws or sliding hip screws. J Orthop Trauma. 2009;23(6):403-7.

Parker MJ, Blundell BR. Choice of implants for internal fixation of femoral neck fractures: meta-analysis of 25 randomized trials including 4,925 patients. Acta Orthop Scand. 1998;69:138-43.

Parker MJ. Evidence-based results depending on the implant used for stabilizing femoral neck fractures. Injury. 2002;33(3):15-8.

Rydell N. Biomechanics of the hip-joint. Clin Orthop. 1973;92:6-15.

Madsen F, Linde F, Andersen E. Fixation of displaced femoral neck fractures. A comparison between sliding screw plate and four cancellous bone screws. Acta Orthop Scand. 1987;58:212-6.

Kreder HJ. Arthroplasty led to fewer failures and more complications than did internal fixation for displaced fractures of the femoral neck. J Bone Joint Surg Am. 2002;84:2108.

Khan M, Aleem IS, Poolman RW. Fixation versus primary replacement of displaced femoral neck fractures in the elderly. Indian J Orthop. 2011;45:23-6.

Rehnberg L, Olerud C. Fixation of femoral neck fractures: Comparison of the Uppsala and Von Bahr screws. Acta Orthop Scand. 1989;60:579-84.

Aminian A, Gao F, Fedoriw WW, Zhang LQ, Kalainov DM, Merk BR. Vertically oriented femoral neck fractures: mechanical analysis of four fixation techniques. J Orthop Trauma. 2007;21:544-8.

Swiontkowski MF, Harrington RM, Keller TS, Patten VPK. Torsion and bending analysis of internal fixation techniques for femoral neck fractures: the role of implant design and bone density. J Orthop Res. 1987;5:433-44.

Upadhyay A, Jain P, Mishra P, Maini L, Gautum VK, Dhaon BK. Delayed internal fixation of fractures of the neck of the femur in young adults. J Bone Joint Surg Br. 2004;86:1035-40.

Baumgaertner MR, Curtin SL, Lindskog DM, Keggi JM. The value of the tip-apex distance in predicting failure of fixation of peri trochanteric fractures of the hip. J Bone Joint Surg Am. 1995;77:1058-64.

Bonnaire FA, Weber AT. Analysis of fracture gap changes, dynamic and static stability of different osteo-synthetic procedures in the femoral neck. Injury. 2002;33(3):24-32.

Simmermacher RK, Bosch AM, Werken VDC. The AO/ASIF-proximal femoral nail (PFN): a new device for the treatment of unstable proximal femoral fractures. Injury. 1999;30:327-32.

Rehnberg L, Olerud C. The stability of femoral neck fractures and its influence on healing. J Bone Joint Surg Br. 1989;71:173-7.

Aitken JM. Relevance of osteoporosis in women with fracture of the femoral neck. Br Med J Clin Res. 1984;288:597-601.

Visna P, Beitl E, Smidl Z, Kalvach J, Pilny J. Treatment of intracapsular femoral neck fractures with the use of a proximal femoral nail. Acta Chir Orthop Traumatol Cech. 2007;74(1):37-46.

Huang H, Su Y, Chen C, Chiu F, Liu C. Displaced femoral neck fractures in young adults treated with closed reduction and internal fixation. Orthopedics. 2010;33(12):873.

Haidukewych GJ, Rothwell WS, Jacofsky DJ, Torchia ME, Berry DJ. Operative treatment of femoral neck fractures in patients between the ages of fifteen and fifty years. J Bone Joint Surg Am. 2004;86:1711-6.

Scheck M. The significance of posterior comminution in femoral neck fractures. Clin Orthop Relat Res. 1980;152:138-42.






Original Research Articles