Variations in Laxity After Total Knee Arthroplasty Do Not Affect Prosthesis-generated Noise
Nicholas F Cozzarelli1, Alexandra L Hohmann2, Irfan A Khan3
1Hackensack University Medical Center, Department of Orthopaedic Surgery, Hackensack, New Jersey.
Background:
Prosthesis-generated noise following total knee arthroplasty (TKA) may affect patient satisfaction and function. The advent of robotic-assisted TKA (RA-TKA) allows for objective knee laxity measurements. The purpose of this study was to compare knee laxity measurements in RATKA patients with and without reported noise generation.
Materials And Methods:
This was a single-institution, retrospective study of 133 patients who underwent primary unilateral RA-TKA from 2018 to 2021. Patients completed a survey consisting of four Likert scale questions related to prosthesis noise, the Forgotten Joint Score (FJS), and the Knee Injury and Osteoarthritis Outcome Score-Joint Replacement (KOOS, JR). Intraoperative laxity measures were obtained from the robotic system and compared between patients who did and did not report noise generation.
Results:
Of the patients, 57.9% did not report noise and 42.1% did report noise. There were no significant differences in medial extension laxity (1.7 mm vs 1.8 mm; P = .454), lateral extension laxity (1.9 mm vs 2.0 mm; P = .567), medial flexion laxity (2.2 mm vs 2.0 mm; P = .419), and lateral flexion laxity (2.7 mm vs 2.9 mm; P = .307). Compared to patients who reported noise, those who did not had significantly higher satisfaction (94.8% vs 37.5%; P < .001), postoperative KOOS, JR scores (79.2% vs 69.7%; P = .005), and FJSs (60.3 vs 44.2; P = .002). Patients who felt noise also had higher satisfaction (90.0% vs 41.5%, P < .001).
Conclusion:
While prosthesis-generated noise symptoms affect satisfaction following TKA, variability in knee laxities does not seem to significantly affect whether a patient will experience noise following TKA.
