Restricted kinematic alignment may be associated with increa
A Study was conducted to compare clinical and radiological results between kinematic alignment (KA) and mechanical alignment (MA) with a posterior-stabilized (PS) total knee arthroplasty (TKA) with a post-cam mechanism at a minimum follow-up of 3 years. The researchers hypothesized a higher risk of aseptic loosening when performing KA using PS TKA.

A retrospective monocentric single surgeon case control study was performed comparing 100 matched patients who had TKA performed using a MA philosophy to 50 patients receiving TKA with a KA technique. All patients had the same knee prosthesis. Patient specific cutting blocks were used in both groups and a restricted KA (rKA) was aimed in the KA group. A hybrid cementation technique was performed. Comparisons between groups were done with the T test or Fisher exact test.

--Mean follow-up was 42.9 months and 53.3 months for rKA and MA groups.

--Postoperatively, no significant differences were found for clinical scores between both groups.

--Radiological assessment found similar postoperative Hip–Knee–Ankle angle for rKA and MA groups.

--At last follow-up, a significant higher survivorship was found for the MA group compared to the rKA group for aseptic loosening revision as the endpoint.

Conclusively, at short-term follow-up, rKA was observed to have a higher risk of tibial implant loosening than MA employing a posterior-stabilized TKA with a post-cam system. When executing rKA, care should be made when selecting the TKA design.