Influence of navigation system updates on total knee arthroplasty

Area of Science:

• Orthopedic Surgery
• Medical Device Technology
• Biomechanical Engineering

Background:

• Total knee arthroplasty (TKA) outcomes can be influenced by surgical technique and technology.
• Image-free computer-assisted navigation systems are utilized to improve precision in TKA.

Purpose of the Study:

• To evaluate the impact of an updated image-free computer-assisted navigation system (Stryker 4.0 vs. 3.1) on total knee arthroplasty outcomes.

Main Methods:

• A comparative study involving 33 knees implanted with Stryker 3.1 and 49 knees with Stryker 4.0 navigation systems.
• Component positioning accuracy was assessed via radiographs and CT scans.
• Operating time and clinical outcomes at one year post-surgery were compared.

Main Results:

• The Stryker 4.0 group demonstrated improved accuracy in frontal femoral and tibial component angles (92% and 94% ideal placement, respectively) compared to the 3.1 group (88% for both).
• Operating time was significantly reduced with the Stryker 4.0 system (125 min) versus the 3.1 system (137 min).
• No statistically significant differences were found in component positioning or one-year postoperative clinical outcomes between the two navigation system versions.

Conclusions:

• The update from Stryker 3.1 to 4.0 navigation system in TKA resulted in a significant reduction in operative time.
• Despite a trend towards improved component alignment with the newer system, no significant differences in component positioning accuracy or clinical outcomes were observed.