Hiroyuki Tsukiyama1, Shinichi Kuriyama2, Masahiko Kobayashi3, Shinichiro Nakamura4, Moritoshi Furu4, Hiromu Ito4, Shuichi Matsuda4. 1. Department of Orthopaedic Surgery, Hyogo Prefectural Amagasaki Hospital, Hyogo, Japan. 2. Department of Orthopaedic Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan. Electronic address: kuriyama@kuhp.kyoto-u.ac.jp. 3. Department of Orthopaedic Surgery, Kyoto Shimogamo Hospital, Kyoto, Japan. 4. Department of Orthopaedic Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
Abstract
BACKGROUND: It is commonly thought that balanced medial and lateral tibiofemoral joint gaps are essential, but the effect of joint laxity on clinical outcome after total knee arthroplasty (TKA) is unclear. It was hypothesised that medial joint laxity correlates with inferior patient satisfaction and knee function, although lateral joint laxity is allowed to a certain degree in TKA. METHODS: This study included 50 knees that underwent primary TKA. Knee laxity was measured with postoperative stress radiographs in flexion and extension, and patient satisfaction and knee function were evaluated by the 2011 Knee Society Knee Scoring System. RESULTS: In a comparison of medially tight and medially loose knees in flexion, the scores for satisfaction, symptoms, standard activity, and advanced activity were significantly better in medially tight than in medially loose knees (satisfaction: 29.8, 22.2; symptoms: 20.3, 15.9; standard activities: 24.2, 19.1; and advanced activities: 15.3, 8.7, in the tight and loose knees, respectively). Neither lateral joint laxity during knee flexion nor medial joint laxity during knee extension was associated with a poor postoperative clinical outcome, whereas lateral joint laxity and the standard activity score in extension had a moderate positive correlation. CONCLUSIONS: Knees with medial joint laxity during flexion resulted in an inferior postoperative outcome, and lateral joint laxity did not influence patient satisfaction or function. Care should be taken to maintain medial joint stability during the TKA procedure.
BACKGROUND: It is commonly thought that balanced medial and lateral tibiofemoral joint gaps are essential, but the effect of joint laxity on clinical outcome after total knee arthroplasty (TKA) is unclear. It was hypothesised that medial joint laxity correlates with inferior patient satisfaction and knee function, although lateral joint laxity is allowed to a certain degree in TKA. METHODS: This study included 50 knees that underwent primary TKA. Knee laxity was measured with postoperative stress radiographs in flexion and extension, and patient satisfaction and knee function were evaluated by the 2011 Knee Society Knee Scoring System. RESULTS: In a comparison of medially tight and medially loose knees in flexion, the scores for satisfaction, symptoms, standard activity, and advanced activity were significantly better in medially tight than in medially loose knees (satisfaction: 29.8, 22.2; symptoms: 20.3, 15.9; standard activities: 24.2, 19.1; and advanced activities: 15.3, 8.7, in the tight and loose knees, respectively). Neither lateral joint laxity during knee flexion nor medial joint laxity during knee extension was associated with a poor postoperative clinical outcome, whereas lateral joint laxity and the standard activity score in extension had a moderate positive correlation. CONCLUSIONS: Knees with medial joint laxity during flexion resulted in an inferior postoperative outcome, and lateral joint laxity did not influence patient satisfaction or function. Care should be taken to maintain medial joint stability during the TKA procedure.
Authors: John M Keggi; Edgar A Wakelin; Jan A Koenig; Jeffrey M Lawrence; Amber L Randall; Corey E Ponder; Jeffrey H DeClaire; Sami Shalhoub; Stephen Lyman; Christopher Plaskos Journal: Arch Orthop Trauma Surg Date: 2021-07-13 Impact factor: 3.067
Authors: Shady S Elmasry; Peter K Sculco; Mohammad Kia; Cynthia A Kahlenberg; Michael B Cross; Andrew D Pearle; David J Mayman; Timothy M Wright; Geoffrey H Westrich; Carl W Imhauser Journal: J Orthop Res Date: 2020-05-25 Impact factor: 3.494