Eu Wei Cheong, Yuik Ho Jade Pei, Kunalan G
Department of Orthopaedic Surgery, Joint Replacement Unit, Kuala Lumpur Hospital, Ministry of Health Malaysia, Jalan Pahang, 50586 Kuala Lumpur, Malaysia.
SICOT J. 2025;11:2. doi: 10.1051/sicotj/2024059. Epub 2025 Jan 13.
Extraarticular deformity (EAD) with knee arthritis is a complex condition involving tri-planar bone deformity with pathological malalignment and chronic soft tissue contracture or laxity in the knee joint. Intraarticular correction by TKA, which was previously performed with conventional manual jig by mechanical alignment technique, had its limits and difficulties especially extensive soft tissue release and risk of jeopardizing the collateral ligaments. Robotic technology allows for reproducible and precise execution of surgical plan and allows adjustment to various new personalised alignment philosophy including functional alignment (FA). FA technique involves the adjustment of components positioning that least compromise the soft tissue envelope while restoring the limb alignment and joint obliquity to create a balanced knee. The aim is to study the outcome of intra-articular correction by robotic assisted TKA using Functional Alignment (FA) technique.
This is a single surgeon series of 8 patients with extraarticular deformity who underwent robotic assisted total knee arthroplasty (TKA) with FA technique. Soft tissue release was gradually released and followed by adjustments of implant positioning in order to achieve a balanced medio-lateral gap.
Postoperatively, the lower limb alignment of all patients were restored within 6° (mean 4.54°) based on functional alignment boundaries. Knee phenotype and joint line obliquity (JLO) were restored in comparison to contralateral lower limb. There were 6 varus and 2 valgus malalignment. 7 patients were implanted with posterior stabilized implants while 1 was implanted with cruciate retaining implant. Arc of knee flexion and extension improved (P = 0.002). There was a large postoperative improvement in the Knee Society Score (KSS) (P < 0.001).
Intraarticular correction by TKA for EAD with knee arthritis is technically reliable with robotic technology. It allows intraoperative adjustment following functional alignment philosophy, thereby, restoring pre-arthritic alignment, knee phenotype and joint line obliquity.
膝关节关节炎合并关节外畸形（EAD）是一种复杂的病症，涉及三平面骨畸形、病理性排列不齐以及膝关节慢性软组织挛缩或松弛。以往通过机械对线技术使用传统手动夹具进行全膝关节置换术（TKA）的关节内矫正存在局限性和困难，尤其是广泛的软组织松解以及损伤侧副韧带的风险。机器人技术能够可重复且精确地执行手术计划，并允许根据包括功能对线（FA）在内的各种新的个性化对线理念进行调整。FA技术涉及调整组件位置，在恢复肢体对线和关节倾斜度以创建平衡膝关节的同时，对软组织包膜的影响最小。目的是研究采用功能对线（FA）技术的机器人辅助TKA进行关节内矫正的效果。
这是一组由单一外科医生完成的系列研究，纳入8例接受机器人辅助全膝关节置换术（TKA）并采用FA技术治疗关节外畸形的患者。逐渐松解软组织，随后调整植入物位置以实现内外侧间隙平衡。
术后，根据功能对线边界，所有患者的下肢对线恢复至6°以内（平均4.54°）。与对侧下肢相比，膝关节形态和关节线倾斜度（JLO）得以恢复。存在6例内翻和2例外翻畸形。7例患者植入后稳定型植入物，1例植入保留交叉韧带的植入物。膝关节屈伸弧度改善（P = 0.002）。膝关节协会评分（KSS）术后有显著改善（P < 0.001）。
对于膝关节关节炎合并EAD的患者，采用机器人技术进行TKA的关节内矫正在技术上是可靠的。它允许根据功能对线理念进行术中调整，从而恢复关节炎前的对线、膝关节形态和关节线倾斜度。
