Knee pain continues to be one of the top five reasons for revision knee replacement. Adverse knee pain has been reported in 10 to 34% of all total knee arthroplasty (TKA). Up to 20% of those patients complain of more pain post-operatively than preoperatively.1
Tibial component malrotation and overhang, and femoral component over-sizing can cause pain and limited flexion leading to early revision surgery after TKA. Gaining the correct rotational position with a symmetrical tibial component remains challenging and relies on a compromise between optimal bony coverage and optimal rotation. Traditional femoral sizing schemes have large increments between sizes and offer only a standard width per femoral size. This can cause implant oversizing leading to pain.2
The authors hypothesised that using a more personalized prosthesis with an anatomically shaped tibial component, and femoral components with fine sizing increments and both standard and narrow widths, would improve the prosthetic fit to patients. This would reduce the potential for soft tissue impingement and pain, and so reduce the number of associated revisions.2
The study reported on 235 patients (237 knees) undergoing a primary cemented TKA between May 2012 and June 2015. All surgeries were performed by two senior surgeons who used the same posterior stabilized knee. The mean follow-up was 75 months (range 60-96 months). 54 patients (23%) required the use of a narrow femoral component. A short cemented tibial stem was used in any patients with a body mass index > 35. 45 patients (19%) required a short cemented tibial stem.2
At the final follow-up, 3 knees required reoperation. One of which required an implant revision. Two of the reoperations were for infection and were treated by debridement lavage, polyethylene insert exchange, and antibiotic therapy. The implant revision was performed at 4 years for tibial loosening and migration in a patient with severe osteopenia. This means that at 5-year follow-up survival without reoperation was 98.72%, while survival without revision for aseptic failure was 99.57%.2
