Holding Power of Orthopaedic Screws in Femora of Young Calves

Summary

The holding power and holding power per mm bone width of 4.5 mm and 5.5 mm cortical and 6.5 mm cancellous orthopaedic screws were obtained by load-to-failure studies in excised femora of young female Holstein calves. Mean ( ± SD) holding power (HP), holding power per mm bone width (HPBW), and holding power per cortical bone width (HPCW) of 4.5 mm (179.67 ± 59.74 kg), 5.5 mm (171.46 ± 76.52 kg), and 6.5 mm orthopaedic screws (191.10 ± 56.67 kg) were not significantly different. The HP, HPBW, HPCW, bone width (BW), and cortical width (CW) were not different between left and right femora. The greatest HP was obtained in the proximal femoral diaphysis, while the smallest HP was observed in the proximal and distal metaphysis. The increase in HP was related to the increase in CW, but was not related to the BW. The CW at the insertion sites of orthopaedic screws in femora was significantly less than in metacarpi and metatarsi. The limiting factor of holding power in all tests was the shear strength of the bone.

This study compares the holding power, holding power per mm bone width, and holding power per mm cortical width of 4.5 mm and 5.5 mm cortical and 6.5 mm cancellous orthopaedic screws in excised femora of young female Holstein calves. The holding power, holding power per mm bone width, and holding power per mm cortical width of different screws were not significantly different.

Keywords

Holding power - orthopaedic screw - calf - femur

• REFERENCES

• 1 Ferguson JG, Dehghani S, Petrali EH. Fractures of the femur in newborn calves. Can Vet J 1990; 31: 289-91.
• 2 Ferguson JG. Management and repair of bovine fractures. Comp Cont Educ Pract Vet 1982; 4: 128-35.
• 3 Crawford WH, Fretz PB. Long bone fractures in large animals. A retrospective study. Vet Surg 1985; 14: 295-302.
• 4 Tulleners EP. Management of bovine orthopaedic problems. Part I. Fractures. Comp Cont Educ Pract Vet 1986; 8: 69-80.
• 5 St-Jean G, DeBowes RM, Hull BL, Constable PD. Intramedullary pinning of diaphyseal femoral fractures in neonatal calves: 12 cases (1980-1990). J Am Vet Med Assoc 1992; 23050: 1372-6.
• 6 Ferguson JG. Investigation of bone strength, density, and fracture biomechanics of the newborn calf femur. Proc World Congress on Diseases of Cattle 1988; 15: 1167-70 (Abstract).
• 7 Ferguson JG. Principles and application of internal fixation in cattle. Vet Clin North Am [Food Animal Practice] 1985; 1: 139-50.
• 8 Ferguson JG. Special considerations in bovine orthopaedics and lameness. Vet Clin North Am [Food Animal Practice] 1985; 1: 131-8.
• 9 Ames NK. Comparison of methods for femoral fracture repair in young calves. J Am Vet Med Assoc 1981; 179: 458-9.
• 10 Nemeth F. Treatment of supracondylar fractures of the femur in large animals. Proc World Congress on Diseases of Cattle 1982; 2: 791-4 (Abstract).
• 11 Kirker-Head CA, Fackclman GE. Use of the cobra head bone plate for distal long bone fractures in large animals. A report of four cases. Vet Surg 1989; 18: 227-34.
• 12 Johnston SA, Lancaster RL, Hubbard RP, Probst CW. A biomechanical comparison of 7-hole 3.5 mm broad and 5-hole 4.5 mm narrow dynamic compression plates. Vet Surg 1991; 20: 235-9.
• 13 Hughes AN, Jorden BA. The mechanical properties of surgical bone screws and some aspects of insertion practice. Injury 1972; 4: 25-38.
• 14 Yovich JV, Turner AS, Smith FW. Holding power of orthopaedic screws in equine third metacarpal and metatarsal bones. Part I. Foal Bone. Vet Surg 1985; 14: 221-9.
• 15 Yovich JV, Turner AS, Smith FW. Holding power of orthopaedic screws in equine third metacarpal and metatarsal bones. Part II. Adult horse bone. Vet Surg 1985; 14: 230-4.
• 16 Vangsness CT, Carter DR, Frankcl VH. In vitro evaluation of the loosening characteristics of self-tapped and non-self-tapped cortical bone screws. Clin Orthop 1981; 157: 279-86.
• 17 Ansell RH, Scales JT. A study of some factors which affect the strength of screws and their insertion and holding power in bone. J Biomech 1968; 1: 279-302.
• 18 Nunamaker DM, Perren SM. Force measurements in screw fixation. J Biomech 1976; 9: 669-75.
• 19 Koranyi E, Bowman CE, Knccht CD, Janssen M. Holding power of orthopaedic screws in bone. Clin Orthop 1970; 72: 283-6.
• 20 Kirpenstcijn J, St-Jcan G, Roush JK. et al. Holding power of orthopaedic screws in metacarpal and metatarsal bones of young calves. V.C.O.T. 1992; 3: 13050-3.
• 21 Getty R. Equine osteology. In: Sisson and Grossman’s The anatomy of the domestic animals. Getty R. (ed). Philadelphia: Saunders; 1975: 255-348.