Department of Orthopedic surgery, Barun Hospital, 145, Yeouidaebang-ro, Yeongdeungpo-gu, Seoul, Korea.
Department of Orthopedic Surgery, Asan Medical Center, University of Ulsan College of Medicine, 88, Olympic-ro 43-gil, Songpa-gu, 05505 Seoul, Korea.
Orthop Traumatol Surg Res. 2024 Apr;110(2):103787. doi: 10.1016/j.otsr.2023.103787. Epub 2023 Dec 7.
The limb length change (LLC) after total knee arthroplasty (TKA) is especially significant in valgus deformity. The higher LLC could cause higher incidences of lower limb length discrepancy (LLD) and low clinical score. However, studies about LLC after TKA for valgus deformity are limited, and there are none on the relationship between LLC and fixed flexion deformity (FFD) in valgus deformity.
(1) The amount of LLC would affect the postoperative LLD, (2) the improvement of fixed flexion deformity (FFD) would affect the amount of LLC, (3) The amount of LLC would affect the improvement in the clinical score after TKA for valgus deformity.
Fifty knees of 50 patients who underwent primary unilateral TKA for valgus-type osteoarthritis between January 2000 and October 2021 were included. A radiological and clinical assessment were performed the day before the operation and at 12 months post-operatively. Full-length standing anteroposterior radiographs were used to measure HKA and LLC. FFD and Hospital for Special Surgery (HSS) score were measured in the outpatient department.
The incidence of lengthening was 92.0% and the mean LLC was 18.85mm (SD, 19.60mm). Postoperative LLD over 10mm occurred in 26% and the mean of postoperative LLD was 4.21mm (SD, 7.96mm). The LLC was correlated with postoperative LLD (rs=0.357, p=0.011) and the HKA change (rs=0.375, p=0.007), but not with the FFD improvement (rs=0.164, p=0.255) and HSS improvement (rs=0.076, p=0.613) or postoperative HSS (rs=0.094, p=0.528).
LLC was affected by HKA improvement but not by FFD improvement after TKA for patients with valgus deformity. Additionally, LLC did not affect the clinical score.
III; retrospective cohort study.
全膝关节置换术（TKA）后肢体长度变化（LLC）在膝关节外翻畸形中尤为重要。较高的 LLC 可能会导致更高的下肢长度差异（LLD）和较低的临床评分。然而，关于膝关节外翻畸形 TKA 后 LLC 的研究有限，且膝关节外翻畸形中 LLC 与固定屈曲畸形（FFD）之间的关系尚无研究。
（1）LLC 的量会影响术后 LLD；（2）固定屈曲畸形（FFD）的改善会影响 LLC 的量；（3）LLC 会影响膝关节外翻畸形 TKA 后的临床评分改善。
纳入 2000 年 1 月至 2021 年 10 月间因膝关节外翻型骨关节炎行初次单侧 TKA 的 50 例 50 膝。术前及术后 12 个月进行放射学和临床评估。全长站立前后位 X 线片用于测量 HKA 和 LLC。FFD 和特种外科医院（HSS）评分在门诊进行测量。
伸长发生率为 92.0%，平均 LLC 为 18.85mm（标准差 19.60mm）。术后 LLD 超过 10mm 的发生率为 26%，平均术后 LLD 为 4.21mm（标准差 7.96mm）。LLC 与术后 LLD 相关（rs=0.357，p=0.011）和 HKA 变化相关（rs=0.375，p=0.007），但与 FFD 改善无关（rs=0.164，p=0.255）和 HSS 改善无关（rs=0.076，p=0.613）或术后 HSS 无关（rs=0.094，p=0.528）。
膝关节外翻畸形 TKA 后，LLC 受 HKA 改善的影响，而不受 FFD 改善的影响。此外，LLC 不影响临床评分。
III；回顾性队列研究。
