Abstract
Previous studies have suggested that three rather than two screws may give better results in the treatment of femoral neck fractures. In the present study, the strength of various screw/bone constructs in femoral neck osteotomy was analyzed. Transverse osteotomies on 65 cadaver femora were fixed with two or three screws of two types: one with a shank diameter of 6 mm and thread diameter of 8 mm, and a prototype screw with equal shank and thread diameter of 7 mm. The femoral heads were subjected to static and cyclic loads in the one-legged stance position. Single-energy quantitative computed tomography measurements were correlated to load. The two experimental models resulted in different patterns of failure of the bone/implant constructs, otherwise the results were similar. Three of the prototype screws gave the strongest construct, while two of the other screw type were stronger than three. The explanations for the diverging properties of the different bone/implant constructs may be that large threads destroy too much of the bone trabeculae, and that screw threads larger than the shank may destroy the drill canal and produce an unstable situation compared with screws with equal shank and thread diameter.
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References
Alho A, Husby T, Høiseth A (1988) Bone mineral content and mechanical strength. An ex vivo study on human femora at autopsy. Clin Orthop 227:292–297
Barnes R, Brown JT, Garden RS, Nicoll EA (1976) Subcapital fractures of the femur. A prospective review. J Bone Joint Surg [Br] 58:2–24
Esses SI, Lotz JC, Hayes WC (1989) Biomechanical properties of the proximal femur determined in-vitro by single-energy quantitative computed tomography. J Bone Miner Res 4:715–722
Hirsch C, Frankel VH (1960) Analysis of forces producing fractures of the proximal end of the femur. J Bone Joint Surg [Br] 42:633–639
Holmberg H, Mattson P, Dahlborn M, Ersmark H (1990) Fixation of 220 femoral neck fractures. A prospective comparison of the Rydell nail and the LIH hook pins. Acta Orthop Scand 61:154–157
Husby T, Alho A, Høiseth A, Fønstelien E (1987) Strength of femoral neck fracture fixation. Comparison of six techniques in cadavers. Acta Orthop Scand 58:634–637
Husby T, Alho A, Nordsletten L, Bugge W (1989) Early loss of fixation of femoral neck fractures. Comparison of three devices in 244 cases. Acta Orthop Scand 60:69–72
Husby T, Benterud J, Alho J, Høiseth A (1990) Screw fixation of femoral neck osteotomy — autopsy study. Acta Orthop Scand 61 [Suppl 237]:83
Larsson S, Elloy M, Hansson LI (1988) Fixation of trochanteric hip fractures. A cadaver study of static and dynamic loading. Thesis, University of Umeå, Sweden
Linde F, Andersen E, Hvass I, Madsen F, Pallesen R (1986) Avascular femoral head necrosis following fracture fixation. Injury 17:159–163
Lotz J, Hayes WC (1990) The use of quantitative computed tomography to estimate risk of fracture of the hip from falls. J Bone Joint Surg [Am] 72:689–700
Rehnberg L, Olerud C (1988) Subchondral screw fixation in the treatment of femoral neck fractures. Thesis, Uppsala University, Sweden
Stappaerts KH (1985) Early fixation failure in displaced femoral neck fractures. Arch Orthop Trauma Surg 104:314–318
Strömqvist B, Hansson LI, Palmer J, Ceder L, Thorngren KG (1983) Scintimetric evaluation of nailed femoral neck fractures with special reference to type of osteosynthesis. Acta Orthop Scand 54:340–347
Swiontkowski MF, Harrington RM, Keller TS, Van Patten PK (1987) Torsion and bending analysis of internal fixation. Techniques for femoral neck fractures: the role of implant design and bone density. J Orthop Res 5:433–444
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Benterud, J.G., Alho, A. & Höiseth, A. Implant/bone constructs in femoral neck osteotomy. Arch Orthop Trauma Surg 113, 97–100 (1994). https://doi.org/10.1007/BF00572914
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DOI: https://doi.org/10.1007/BF00572914