Effects of Partial Medial Meniscectomy on Load Distribution and Anterior Displacement of the Proximal Tibia. - A Biomechanical Study in Dogs

Abstract

In this experimental study, 12 knees of mongrel dogs were used to investigate the effects of partial medial meniscectomy on the load distribution and postero-anterior displacement of the proximal tibia. Two pairs of strain gauges, one vertically and the other horizontally oriented, were placed on the lateral and medial sides of the proximal tibia. The specimens were cut at 300 mm from the joint line proximally and distally. Forces of 50 and 100 Newtons were applied on the models and axial and sliding tensions were measured before and after partial medial meniscectomy with a special test instrument in which axial compression was applied by means of a rotary moment. Anterior displacement of the proximal tibia after a 10 N load in the postero-anterior direction was also measured with a comperator. Statistical analysis was done using a student t test. After partial medial meniscectomy , axial tensions resulting from axial loads of 5O N increased by 25% and sliding tension increased by 19.5%. The same values were increased by 44% and 65% respectively when the axial load was increased to 100 N. Anterior displacement of the proximal tibia after a load of 10 N increased by 95% after partial medial meniscectomy. All the differences were statistically significant.