Abstract
Introduction The purpose of this study was to detect the effect of tibial slope on maximal flexion after TKA.
Methods Twenty-one cadaver implantations of a standard PCL-retaining TKA were performed with increasing tibial slope of zero degrees, four degrees and seven degrees. For every specimen all variables except slope were kept constant, including tibio-femoral contact locations in deep flexion, which were determined upon in vivo contact patterns that were obtained during maximal squatting activities in patients that had undergone TKR with the same design. Maximal flexion was determined by direct impingement of the tibial component on the posterior femoral bone fluoroscopy.
Results Maximal flexion correlated positively with increasing slope (p< 0.001, R2 = 0.8). When aimed slope was considered, flexion increased on average 2.2° for every degree of downslope. When obtained slope was considered, flexion increased on average 1.7° for every degree of downslope.
Conclusions In PCL-retaining TKA, maximal obtainable flexion icnreases on average two degrees per degree extra tibial slope.
In relation to the conduct of this study, one or more of the authors has received, or is likely to receive direct material benefits.
The abstracts were prepared by Mr Jerzy Sikorski. Correspondence should be addressed to him at the Australian Orthopaedic Association, Ground Floor, William Bland Centre, 229 Macquarie Street, Sydney NSW 2000, Australia.
