Mechanical comparison of the Youngswick, sagittal V, and modified Weil osteotomies for hallux rigidus in a sawbone model.
The purpose of this study was to compare the mechanical properties of 3 osteotomies often used for hallux rigidus. Maximum load, failure energy, stiffness, and fracture pattern were determined for 3 different test models as well as a control group. Twenty-eight first metatarsal polyurethane sawbone models were equally divided into 4 groups. The osteotomy groups tested consisted of a Youngswick, sagittal V, and modified Weil-type osteotomy of the first metatarsal. Each osteotomy was fixated with a 2.7-mm cortical screw, all 16 mm in length, and a small diameter smooth wire, both placed perpendicular to the osteotomy. Each model was then loaded to failure in a servo-hydraulic material testing machine. Results for maximum load to failure for all 4 constructs showed a mean range of 15.1 to 33.7 N, a mean energy to failure ranging from 0.04 to 0.8 J, and stiffness from 1.5 to 3.4 N/mm. Significant differences in peak load and stiffness (P = .015 for peak load, P = .025 for stiffness) were found between the sagittal V group versus the control and between the modified Weil and sagittal V group (P = .037 for peak load, P = .017 for stiffness). There were no significant differences in the energy to failure between the 4 groups (P > .083). These findings suggest that the sagittal V osteotomy construct was significantly weaker and less stiff than the modified Weil.
LaMar
Laura
L
St. John North Shores Hospital, 26755 Ballard Road, Harrison Township, MI 48045, USA. lamarlau@hotmail.com
Deroy
Alan R
AR
Sinnot
Michael T
MT
Haut
Roger
R
Squire
Mark
M
Wertheimer
Stuart
S
D001863:Bone Screws; D050723:Fractures, Bone; D020859:Hallux Rigidus / Q000601:surgery*; D006801:Humans; D008682:Metatarsal Bones / Q000601:surgery; D008953:Models, Anatomic; D010027:Osteotomy / Q000379:methods*; D011140:Polyurethanes; D016474:Weight-Bearing
D011140:Polyurethanes