Objectives: In some total knee arthroplasty cases, the usual medial parapatellar approach does not allow the appropriate patellar eversion and the desired exposure of the knee joint. Partial disinsertion of the patellar tendon doesn't substantially improve the surgical exposure and can lead to extensor apparatus weakening and complete secondary ruptures, while the V-Y quadricipital plasty leads to post-op immobilization of the knee, which delays the functional rehabilitation, with negative impact on the range of motion. The tibial tubercle osteotomy, however, allows an extension of the approach in total knee arthroplasty, without endangering the quadricipital extensor apparatus.
Material and methods: In this study we analysed the post-operative results of 11 cases of primary total knee arthroplasty in which a frontal plane osteotomy of the tibial tubercle was performed in addition to the standard medial parapatellar approach, as a result of the patients associated conditions, like rheumatoid arthritis with an extension deficit higher than 150, previous knee synovectomy by arthrotomy, progressive genu varum with more than 150 deviation, varus deviation of the lower limb with previous closing wedge proximal tibial osteotomy or patellar fractures with vicious consolidation.
Outcomes: Overall, the results were more than satisfactory with a significant increase in the patients mean range of motion and Knee Society Score. There were some post-op issues in some of the patients, but they were adressed accordingly, having no long-term impact on the results.
Conclusions: . We could thus conclude that, in special cases, the frontal plane tibial tubercle osteotomy is an effective technique which can provide a wide approach with appropriate protection of the knee extensor apparatus.
Keywords: arthroplasty; knee joint exposure; knee range of motion; tibial tubercle osteotomy.