Abstract
High tibial osteotomy is commonly performed for varus/ valgus misalignment of the knee. Altering the sagittal plane can affect the forces of the cruciate ligaments and influence stability. This retrospective study looked at the alteration of the tibial slope produced by closed wedge osteotomy, in which the importance of the sagittal plane is often overlooked.
We followed-up 67 of 80 patients admitted for high tibial osteotomy or removal of hardware between January and September 2001. The mean age of the 41 men was 36.6 years (17 to 67) and of the 26 women 39.4 years (19 to 62).
On preoperative radiographs the mean slope was 6.1( (0( to 12(). The frontal plane was changed by a mean of 7.93( (2( to 12(). A closed wedge osteotomy decreased the slope by a mean of 4.88( (0( to 10( posteriorly and 0( to 6( anteriorly). Alteration of the coronal plane by 6( decreased the slope by 4.29(, 8( by 7(, 10( by 4.75( and 12( degrees by 6.5(.
A closed wedge osteotomy decreases the tibial slope. This causes an anterior shift in the starting position of the tibia, potentially decreasing in situ forces acting on the anterior cruciate ligament. There was no correlation between the correction of the coronal plane and alteration of the sagittal plane.
The abstracts were edited by Prof. M.B.E. Sweet. Correspondence should be addressed to him at the Department of Orthopaedic Surgery, Medical School, University of the Witwatersrand, 7 York Road, Parktown, 2193 South Africa
