Abstract
Aims: Fixed valgus requires lateral releases for stable patellar tracking and gap balancing. Adequate extension space must be achieved without weakening the lateral sleeve. This complication can occur with sub-periosteal femoral LCL/popliteus releases. Distal LCL lengthening and/or lateral epicondylectomy with advancement maintaining soft tissue strength/stability. Methods: 174 valgus TKAs with 5- to 15-year follow-up were reviewed. Demographics included 93% females, 13% rheumatoid, mean age 69. Prostheses utilized were LCS meniscal (30%) and rotating (70%). Fixation was cementless in 86%. The direct lateral approach was used in all cases. Results: Good/excellent results were 91% (HSS scores 54 to 84). Deformity correction mean > 15° to < 5° valgus. Of the failures, 5 were meniscal PCL-retaining (1 malposition, 2 subluxations, 2 wear). Four meniscal and one rotating bearing spin-out were related to inadequate (over/under) concave side balancing, all in early cases with standard femoral sub-periosteal releases. Conclusion: Release of contracted concave side soft tissues, without compromising strength/integrity of the LCL/popliteus complex, is required to achieve stable flexion-extension gap balance and correction of the biomechanical axis in fixed valgus TKA. Improved techniques of lateral side releases that maintain ligament attachments and allow more precise lateral extension gap adjustment have eliminated failures related to soft-tissue imbalance with non-constrained implants. Key technique points of the lateral approach, with emphasis on the deep releases, will be illustrated.
Theses abstracts were prepared by Professor Dr. Frantz Langlais. Correspondence should be addressed to him at EFORT Central Office, Freihofstrasse 22, CH-8700 Küsnacht, Switzerland.
