2026 · Journal of Arthroplasty
로봇 보조 rKA TKA에서 정렬 변화와 수술 중 내·외측 gap이 1–2년 환자보고결과와 어떤 관계를 보일까?
HKA와 LDFA 변화가 작을수록 2년 Knee Society Knee Score가 높았습니다(P = 0.001, 0.013).
연구 구조
- 01대상
rKA 프로토콜로 시행한 로봇 보조 cruciate-retaining TKA 69례.
- 02방법
후향적 코호트 연구입니다. 로봇이 기록한 신전·굴곡의 내·외측 gap과 딥러닝으로 측정한 수술 전후 HKA·LDFA·MPTA를 분석했습니다. 다변량 ANCOVA와 ROC 분석으로 1–2년 PROMs와의 연관성을 평가했습니다.
- 03보고 결과
HKA와 LDFA 변화가 작을수록 2년 Knee Society Knee Score가 높았습니다(P = 0.001, 0.013).
논문의 대상·방법·결과를 구분한 설명용 모식도입니다. 원문 figure가 아닙니다.
초록 해설
대상과 방법
주요 결과
진료·수술에서 읽을 지점
해석의 제한
짧게 정리하면
이 연구가 확인한 것은 무엇인가요?
HKA와 LDFA 변화가 작을수록 2년 Knee Society Knee Score가 높았습니다(P = 0.001, 0.013).
개별 환자의 치료 결정에 바로 적용할 수 있나요?
69례의 후향적 연구이며 결과는 초기 추적에 국한됩니다. ROC 분별력도 제한적이어서 제시된 cut-off를 보편적인 수술 목표로 확정할 수 없습니다. 저자 역시 더 큰 코호트와 장기 검증을 요구했습니다.
Keywords · 주제어
- intraoperative gap balance
- joint line preservation
- restricted kinematic alignment
- robotic-assisted surgery
- total knee arthroplasty
- TKA
- robotics
- joint line
Abstract · 원문 초록
Do Weon Lee, Du Hyun Ro, Hyuk-Soo Han. Limited Femoral Joint-Line Alteration and Preserved Extension Lateral Laxity Enhanced Early Outcomes in Restricted Kinematic Alignment Total Knee Arthroplasty. The Journal of arthroplasty. 2026:S0883-5403(26)00519-X. doi:10.1016/j.arth.2026.05.029.
BACKGROUND
Restricted kinematic alignment (rKA) total knee arthroplasty (TKA) seeks to restore native alignment while limiting excessive correction. The influence of alignment change magnitude and intraoperative gap characteristics on early patient-reported outcome measures (PROMs) after robotic rKA TKA remains unclear.
METHODS
This retrospective cohort study included 69 robotic-arm-assisted cruciate-retaining TKAs performed using an rKA protocol. Intraoperative medial and lateral extension and flexion gaps-extension medial gap, extension lateral gap, flexion medial gap (FMG), and flexion lateral gap-were recorded automatically. Preoperative and postoperative hip-knee-ankle (HKA) angle, lateral distal femoral angle (LDFA), and medial proximal tibial angle were measured using a validated deep learning model. Multivariable analyses of covariance evaluated associations between demographics, baseline alignment, alignment changes, gap characteristics, and PROMs at one and two years.
RESULTS
All PROMs improved postoperatively. Smaller changes in HKA and LDFA were independently associated with higher two-year Knee Society Knee Scores (P = 0.001 and P = 0.013). Greater ELG was associated with a higher two-year Forgotten Joint Score (P = 0.001), whereas greater FMG was associated with lower two-year Western Ontario and McMaster Universities Osteoarthritis Index pain and stiffness scores (P = 0.011 and P = 0.002). Receiver operating characteristic analyses identified changes in LDFA less than 2.3° (area under the curve [AUC] 0.622) and changes in HKA less than 8.4° (AUC 0.541) as thresholds associated with higher Knee Society Knee Score. An ELG ≥ 3.0 mm predicted higher Forgotten Joint Score (AUC 0.658), and FMG ≥ 1.5 mm predicted lower Western Ontario and McMaster Universities Osteoarthritis Index stiffness (AUC 0.716). No revisions occurred.
CONCLUSIONS
In robotic cruciate-retaining rKA TKA, minimizing femoral joint-line alteration and preserving controlled lateral extension laxity, along with mild medial flexion laxity, were associated with modestly improved early outcomes. These findings are exploratory and require validation in larger cohorts with longer follow-up.
원래 논문
Limited Femoral Joint-Line Alteration and Preserved Extension Lateral Laxity Enhanced Early Outcomes in Restricted Kinematic Alignment Total Knee Arthroplasty
Do Weon Lee, Du Hyun Ro, Hyuk-Soo Han
Journal of Arthroplasty · 2026