Getting REAL balance: a simple and reproducible method for imageless robotic TKA.

Q1 Medicine

MUSCULOSKELETAL SURGERY Pub Date : 2026-10-27 DOI:10.1007/s12306-026-00991-4

Stefano Marco Paolo Rossi, Rudy Sangaletti, Chiara Muci, Paolo Capitani, Francesco Benazzo, Luca Andriollo

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引用次数: 0

Abstract

Background: In imageless robotic-assisted total knee arthroplasty (RA-TKA), intraoperative assessment of ligament balance may be influenced by asymmetric cartilage wear, potentially misrepresenting true soft-tissue behavior. Functional alignment (FA) aims to restore constitutional alignment while respecting the native ligament envelope. Using the unworn compartment as the primary reference for intraoperative balancing may reduce the effect of asymmetric wear and improve mediolateral symmetry.

Methods: A retrospective analysis was performed on 180 knees (176 patients) undergoing femur-first imageless RA-TKA with a functional alignment strategy at a single-volume center. All procedures were performed using the ROSA Knee System with a medial congruent implant. Intraoperative balancing prioritized the unworn or less affected compartment, targeting a 19-mm implant space with near-symmetric medial-lateral laxity in extension and flexion. Medial and lateral laxities were recorded robotically before implantation and after final component placement and classified using the Robotic Evaluation of Articular Laxity (REAL).

Results: Preoperatively, lateral laxity exceeded medial laxity in both extension and flexion. Following implantation, mediolateral symmetry was restored with a significant reduction in medial-lateral laxity differences (p < 0.001). At final assessment, 178 knees (98.9%) were classified as REAL 1A. Soft-tissue releases were required in 14 knees (7.8%), with no intraoperative instability, additional bone recuts, or device-related complications.

Conclusions: In femur-first imageless RA-TKA performed according to functional alignment principles, unworn-compartment-based balancing enables reliable restoration of mediolateral ligament symmetry with balanced REAL phenotypes and a limited need for soft-tissue releases, representing a refinement of robotic ligament assessment in knees with asymmetric osteoarthritis during contemporary robotic surgery.

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获得真实平衡：一种简单且可重复的无图像机器人TKA方法。

背景：在无图像机器人辅助全膝关节置换术（RA-TKA）中，术中对韧带平衡的评估可能会受到不对称软骨磨损的影响，这可能会歪曲软组织的真实行为。功能对准（FA）的目的是在尊重原有韧带包膜的同时恢复结构对准。术中使用未磨损的椎间室作为平衡的主要参考，可以减少不对称磨损的影响，改善中外侧对称性。方法：对180个膝关节（176例患者）进行回顾性分析，并在单容积中心采用功能对齐策略进行股骨优先无图像RA-TKA。所有手术均采用ROSA膝关节系统和内侧全等假体进行。术中平衡优先考虑未磨损或受影响较小的隔室，目标是19毫米的种植体空间，其伸展和屈曲接近对称的内外侧松弛。在植入前和最终植入组件后，机器人记录内侧和外侧松弛度，并使用机器人关节松弛度评估（REAL）进行分类。结果：术前，伸展和屈曲时，外侧松弛超过内侧松弛。植入后，内外侧对称性得到恢复，内外侧松弛度差异显著降低（p < 0.001）。在最终评估时，178例膝关节（98.9%）被分类为REAL 1A。14例膝关节（7.8%）需要软组织松解，无术中不稳定、额外的骨切开或器械相关并发症。结论：在根据功能对齐原则进行的股骨优先无图像RA-TKA中，基于非磨损腔室的平衡能够可靠地恢复具有平衡REAL表型的中外侧韧带对称性，并且对软组织释放的需求有限，代表了在当代机器人手术中对不对称骨关节炎膝关节的机器人韧带评估的改进。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

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来源期刊

MUSCULOSKELETAL SURGERY Medicine-Surgery

CiteScore

4.50

自引率

0.00%

发文量

期刊介绍： Musculoskeletal Surgery – Formerly La Chirurgia degli Organi di Movimento, founded in 1917 at the Istituto Ortopedico Rizzoli, is a peer-reviewed journal published three times a year. The journal provides up-to-date information to clinicians and scientists through the publication of original papers, reviews, case reports, and brief communications dealing with the pathogenesis and treatment of orthopaedic conditions.An electronic version is also available at http://www.springerlink.com.The journal is open for publication of supplements and for publishing abstracts of scientific meetings; conditions can be obtained from the Editors-in-Chief or the Publisher.