Tibial tubercule osteotomy during the revision of total knee arthroplasty: The technique of a referral center with 10 years of experience.

Introduction: The Tibial Tubercle Osteotomy (TTO) technique, by lifting the distal bony attachment of the extensor mechanism, allows efficient knee exposure while preserving soft tissues and tendinous attachments. The surgical technique seems essential to obtain satisfying outcomes with a low rate of specific complications. Several tip sand tricks can be used to improve this procedure during the revision of total knee arthroplasty (RTKA).

Technique: The osteotomy should be at least: 60 mm in length and 20 mm in width to allow fixation with 2 screws; and 10-15 mm thick to resist to screw compression. The proximal cut of the osteotomy must keep a proximal buttress spur of 10 mm to get primary stability and avoid the tubercle ascension. A smooth end of the TTO distally reduces the risk of a tibial shaft fracture. The strongest fixation is obtained using two bicortical 4.5 mm screws slightly ascendant.

Results: From January 2010 to September 2020, 135 patients received an RTKA with concomitant TTO and a mean follow-up of 51 ± 26 months [24-121]. The osteotomy was healed in 95% of patients (n = 128) with a mean delay of 3.4 ± 2.7 months [1.5-24]. However, there are some specific and significant complications related to the TTO. Twenty complications (15%) related to the TTO were recorded, with 8 (6%) requiring surgery.

Conclusion: Tibial tubercle osteotomy in RTKA is an efficient procedure to improve knee exposure. To avoid tibial tubercle fracture or non-union, a rigorous surgical technique is primordial with a sufficient length and thickness of the tibial tubercle, a smooth end, a proximal step, a final good bone contact, and a strong fixation.