TY - JOUR
T1 - Improved total knee arthroplasty pain outcome when joint gap targets are achieved throughout flexion
AU - Wakelin, Edgar A.
AU - Shalhoub, Sami
AU - Lawrence, Jeffrey M.
AU - Keggi, John M.
AU - DeClaire, Jeffrey H.
AU - Randall, Amber L.
AU - Ponder, Corey E.
AU - Koenig, Jan A.
AU - Lyman, Stephen
AU - Plaskos, Christopher
N1 - Funding Information:
The authors would like to acknowledge the critical data collection and study administration performed by: Jayne Crofut, Katie Mabee, Sharon Stewart, Cindy Murphy, Kathryn Darley and Alex Friedl, and the data processing and analysis performed by Anna Geraghty. We dedicate this work to the memory of Dr. Leonid Dabuzhsky, 1952 –2019. Dr Dabuzhsky was extremely passionate and actively involved in this project from the start. His contribution was immense, and his unwavering dedication to his patients’ care will continue to inspire us.
Publisher Copyright:
© 2021, European Society of Sports Traumatology, Knee Surgery, Arthroscopy (ESSKA).
PY - 2022/3
Y1 - 2022/3
N2 - Purpose: Achieving a balanced knee is accepted as an important goal in total knee arthroplasty; however, the definition of ideal balance remains controversial. This study therefore endeavoured to determine: (1) whether medio-lateral gap balance in extension, midflexion, and flexion are associated with improved outcome scores at one-year post-operatively and (2) whether these relationships can be used to identify windows of optimal gap balance throughout flexion. Methods: 135 patients were enrolled in a multicenter, multi-surgeon, prospective investigation using a robot-assisted surgical platform and posterior cruciate ligament sacrificing gap balancing technique. Joint gaps were measured under a controlled tension of 70–90 N from 10°–90° flexion. Linear correlations between joint gaps and one-year KOOS outcomes were investigated. KOOS Pain and Activities of Daily Living sub-scores were used to define clinically relevant joint gap target thresholds in extension, midflexion, and flexion. Gap thresholds were then combined to investigate the synergistic effects of satisfying multiple targets. Results: Significant linear correlations were found throughout extension, midflexion, and flexion. Joint gap thresholds of an equally balanced or tighter medial compartment in extension, medial laxity ± 1 mm compared to the final insert thickness in midflexion, and a medio-lateral imbalance of less than 1.5 mm in flexion generated subgroups that reported significantly improved KOOS pain scores at one year (median ∆ = 8.3, 5.6 and 2.8 points, respectively). Combining any two targets resulted in further improved outcomes, with the greatest improvement observed when all three targets were satisfied (median ∆ = 11.2, p = 0.002). Conclusion: Gap thresholds identified in this study provide clinically relevant and achievable targets for optimising soft tissue balance in posterior cruciate ligament sacrificing gap balancing total knee arthroplasty. When all three balance windows were achieved, clinically meaningful pain improvement was observed. Level of Evidence: Level II.
AB - Purpose: Achieving a balanced knee is accepted as an important goal in total knee arthroplasty; however, the definition of ideal balance remains controversial. This study therefore endeavoured to determine: (1) whether medio-lateral gap balance in extension, midflexion, and flexion are associated with improved outcome scores at one-year post-operatively and (2) whether these relationships can be used to identify windows of optimal gap balance throughout flexion. Methods: 135 patients were enrolled in a multicenter, multi-surgeon, prospective investigation using a robot-assisted surgical platform and posterior cruciate ligament sacrificing gap balancing technique. Joint gaps were measured under a controlled tension of 70–90 N from 10°–90° flexion. Linear correlations between joint gaps and one-year KOOS outcomes were investigated. KOOS Pain and Activities of Daily Living sub-scores were used to define clinically relevant joint gap target thresholds in extension, midflexion, and flexion. Gap thresholds were then combined to investigate the synergistic effects of satisfying multiple targets. Results: Significant linear correlations were found throughout extension, midflexion, and flexion. Joint gap thresholds of an equally balanced or tighter medial compartment in extension, medial laxity ± 1 mm compared to the final insert thickness in midflexion, and a medio-lateral imbalance of less than 1.5 mm in flexion generated subgroups that reported significantly improved KOOS pain scores at one year (median ∆ = 8.3, 5.6 and 2.8 points, respectively). Combining any two targets resulted in further improved outcomes, with the greatest improvement observed when all three targets were satisfied (median ∆ = 11.2, p = 0.002). Conclusion: Gap thresholds identified in this study provide clinically relevant and achievable targets for optimising soft tissue balance in posterior cruciate ligament sacrificing gap balancing total knee arthroplasty. When all three balance windows were achieved, clinically meaningful pain improvement was observed. Level of Evidence: Level II.
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U2 - 10.1007/s00167-021-06482-2
DO - 10.1007/s00167-021-06482-2
M3 - Article
C2 - 33580346
AN - SCOPUS:85101428659
SN - 0942-2056
VL - 30
SP - 939
EP - 947
JO - Knee Surgery, Sports Traumatology, Arthroscopy
JF - Knee Surgery, Sports Traumatology, Arthroscopy
IS - 3
ER -