Pinless Navigation in Unicompartmental Knee Arthroplasty.

Area of Science:

• Orthopedic Surgery
• Biomedical Engineering

Background:

• Unicompartmental knee arthroplasty (UKA) aims to preserve native knee biomechanics through resurfacing.
• Accurate tibial component alignment is critical for UKA success and longevity.
• Pinless navigation, successful in total knee arthroplasty (TKA), has not been evaluated for UKA.

Purpose of the Study:

• To investigate the feasibility of using pinless optical navigation for tibial component implantation in UKA.
• To assess if a 3° varus alignment, closer to the anatomical axis, can be achieved with this technique.

Main Methods:

• A prospective study involving 60 patients undergoing UKA.
• Two groups were compared: one using pinless navigation and another using conventional extramedullary guides for tibial component alignment.
• Clinical and radiographic follow-up was conducted within one year.

Main Results:

• 57 patients were analyzed, with no clinical incidents reported.
• Pinless navigation accurately achieved the target 3° varus tibial component alignment, similar to the conventional method.
• Surgical times were comparable, with mean suture times of 43.2 minutes for pinless navigation and 42.7 minutes for the conventional technique.

Conclusions:

• Pinless navigation is an effective method for achieving accurate tibial component alignment in UKA.
• This technique allows for alignment comparable to high-volume surgeons without the need for pins.
• The method presents an irrelevant increase in surgical time, making it a practical alternative.