Background: 

Thigh pain is relatively common after total knee arthroplasty (TKA) and has been attributed to compression of the thigh muscles by the tourniquet used during surgery. Thigh pain that occurs after a TKA that was performed without a tourniquet may be due to a strain of the quadriceps muscle or insertion of the intramedullary (IM) rod. The purpose of the present study was to determine the cause of thigh pain after TKA in a randomized controlled trial evaluating tourniquet use, IM rod use, and quadriceps strain.

Methods: 

This prospective randomized controlled trial enrolled 97 subjects undergoing primary knee arthroplasty into 4 groups according to tourniquet use (yes or no) and IM rod use (yes or no). Quadriceps strain was evaluated with magnetic resonance imaging (MRI) on postoperative day 1 (POD 1). Data collected preoperatively, intraoperatively, and postoperatively until the 6-week clinical visit included pain levels for the knee and thigh (recorded separately) and knee range of motion.

Results: 

Regardless of tourniquet or IM rod use, 73 (75%) of the 97 patients reported thigh pain on POD 1. Thigh pain at 2 weeks postoperatively was indicative of a quadriceps strain. Use of a tourniquet and patient-reported thigh pain at 2 weeks increased the odds of a quadriceps strain, whereas IM rod use did not significantly contribute to thigh pain.

Conclusions: 

The etiology of thigh pain after TKA may be multifactorial; however, an iatrogenic quadriceps strain is one source of thigh pain after TKA, especially if the pain persists 2 weeks after surgery.

Level of Evidence: 

Prognostic Level I. See Instructions for Authors for a complete description of levels of evidence.

中文翻译：

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股四头肌拉伤和 TKA：止血带和髓内棒对术后大腿疼痛的影响：一项随机对照试验

背景： 

大腿疼痛在全膝关节置换术 (TKA) 后相对常见，并且归因于手术期间使用的止血带对大腿肌肉的压迫。在没有止血带的情况下进行 TKA 后出现的大腿疼痛可能是由于股四头肌拉伤或插入髓内 (IM) 杆所致。本研究的目的是在评估止血带使用、肌内注射棒使用和股四头肌拉伤的随机对照试验中确定 TKA 后大腿疼痛的原因。

方法： 

这项前瞻性随机对照试验根据止血带使用情况（是或否）和肌内固定棒使用情况（是或否）将 97 名接受初次膝关节置换术的受试者分为 4 组。在术后第 1 天 (POD 1) 使用磁共振成像 (MRI) 评估股四头肌应变。术前、术中和术后直至 6 周临床访视收集的数据包括膝关节和大腿的疼痛程度（分别记录）和膝关节活动范围。

结果： 

无论使用止血带还是肌肉注射棒，97 名患者中有 73 名 (75%) 报告在 POD 1 时出现大腿疼痛。术后 2 周的大腿疼痛表明股四头肌拉伤。使用止血带和患者报告的大腿疼痛在 2 周时增加了股四头肌拉伤的几率，而使用 IM 棒对大腿疼痛没有显着影响。

结论： 

TKA 后大腿疼痛的病因可能是多方面的；然而，医源性股四头肌拉伤是 TKA 后大腿疼痛的来源之一，尤其是在手术后 2 周疼痛持续存在的情况下。

证据等级： 

预后一级。有关证据等级的完整描述，请参阅作者须知。