Department of Orthopaedic Surgery, Innsbruck Medical University, Anichstrasse 35, 6020 Innsbruck, Austria.
Clin Orthop Relat Res. 2012 Nov;470(11):3233-9. doi: 10.1007/s11999-012-2545-7. Epub 2012 Aug 18.
Less invasive dissection of the extensor apparatus, one of the aspects of minimally invasive surgical (MIS) TKA, might result in less reduction of postoperative quadriceps strength. However, it is unclear whether MIS is associated with less strength reduction.
QUESTIONS/PURPOSES: We asked whether knee strength (extensor or flexor torque) would be greater in patients having a MIS TKA compared with patients having a standard TKA and whether knee scores, alignment, ROM, tourniquet and operating times, and hospital length of stay were improved.
We prospectively recruited 52 patients awaiting MIS or standard TKA, matched for age, weight, height, BMI, sex, and surgically treated side, but not randomized. Isokinetic tests were performed preoperatively and postoperatively to obtain peak values of extensor and flexor torque. Postoperative-to-preoperative ratios and the extensor-flexor torque ratio also were calculated.
Mean baseline extensor torques were 57 Nm and 53 Nm for MIS and standard TKAs, respectively. At 8 weeks postoperatively, absolute values of the mean postoperative knee extensor torque also were similar: 47 and 45 Nm for patients with MIS and standard TKAs, respectively. The postoperative-to-preoperative ratios were 0.8 for extensor and flexor torque in both groups. The extensor-flexor torque ratios were similar between groups.
Our data suggest a less invasive dissection of the extensor apparatus involved in MIS TKA does not enhance postoperative quadriceps strength.
Level III, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.
微创外科（MIS）全膝关节置换术（TKA）的一个方面是对伸肌装置进行微创解剖，这可能导致术后股四头肌力量的减少。然而，目前尚不清楚 MIS 是否与力量减少有关。
问题/目的：我们想知道与标准 TKA 相比，MIS TKA 是否会使患者的膝关节力量（伸肌或屈肌扭矩）更大，以及膝关节评分、对线、ROM、止血带和手术时间以及住院时间是否得到改善。
我们前瞻性地招募了 52 名接受 MIS 或标准 TKA 的患者，按年龄、体重、身高、BMI、性别和手术治疗侧进行匹配，但未进行随机分组。在术前和术后进行等速测试，以获得伸肌和屈肌扭矩的峰值。还计算了术后与术前的比值以及伸肌-屈肌扭矩比。
MIS 和标准 TKA 的基线伸肌扭矩均值分别为 57 Nm 和 53 Nm。术后 8 周，平均术后膝关节伸肌扭矩的绝对值也相似：MIS 和标准 TKA 患者分别为 47 Nm 和 45 Nm。两组伸肌和屈肌的术后与术前比值均为 0.8。两组的伸肌-屈肌扭矩比相似。
我们的数据表明，MIS TKA 中对伸肌装置进行微创解剖不会增强术后股四头肌力量。
III 级，治疗研究。欲了解完整的证据水平描述，请参见作者指南。
