Background: Whether the use of platelet-rich plasma (PRP) as an adjuvant to extensor carpi radialis brevis (ECRB) repair in recalcitrant lateral epicondylitis (RLE) promotes tendon healing and improves clinical outcomes remains unclear.

Purpose: To evaluate the tendon healing and clinical outcomes of arthroscopic ECRB repair combined with PRP injection and compared with arthroscopic ECRB repair alone at early-term follow-up in patients with RLE.

Study design: Randomized controlled trial; Level of evidence, 1.

Methods: A consecutive series of 80 patients with RLE were enrolled and randomized to the PRP group (arthroscopic ECRB repair followed by 1 PRP injection; n = 40) and the control group (arthroscopic ECRB repair alone; n = 40). Magnetic resonance imaging was performed to assess tendon healing at 3, 6, and 12 months. The visual analog scale (VAS) for pain, the Mayo Elbow Performance Score (MEPS), the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire, the Patient-Rated Tennis Elbow Evaluation (PRTEE) scale, range of motion, and muscle strength were evaluated at preoperative and follow-up points. The time to return to work was also compared between the 2 groups. Patients and assessors were blinded to the intervention.

Results: A total of 80 patients who met the inclusion criteria were enrolled between July 2020 and July 2023, and 73 patients completed follow-up. The PRP group contained 35 patients, 11 men and 24 women, with a mean age of 47.8 ± 8.8 years. The control group contained 38 patients, 13 men and 25 women, with a mean age of 44.5 ± 5.8 years. No significant differences were found in magnetic resonance imaging classification and functional scores between groups at preoperative and follow-up periods. VAS, MEPS, DASH, and PRTEE scores and muscle strength showed significant improvement at 12 months in both groups (P < .001). However, the PRP group showed a significant improvement in grip and wrist extension muscle strength at 6 weeks postoperatively (P = .008 and P < .001, respectively), whereas the control group did not (P = .583 and .056). No complications were associated with PRP injection.

Conclusion: PRP used as an adjuvant to ECRB repair did not show a difference in tendon healing and functional outcomes compared with ECRB repair alone for RLE at 12-month follow-up. However, PRP treatment showed a difference in muscle strength at 6-week follow-up compared with ECRB repair alone.

Registration: NCT04556825 (ClinicalTrials.gov).

Keywords: ECRB; arthroscopic; platelet-rich plasma (PRP); recalcitrant lateral epicondylitis; tendon repair.

背景： 尚不清楚在顽固性肘外侧炎（RLE）的伸肌总腱尺侧头（ECRB）修复中使用富含血小板的血浆（PRP）作为辅助治疗是否能促进肌腱愈合并改善临床结果。

目的： 评估关节镜下ECRB修复联合PRP注射与单独进行关节镜下ECRB修复在RLE患者短期随访中的肌腱愈合和临床效果的比较。

研究设计： 随机对照试验；证据级别1级。

方法： 入组连续80名患有顽固性肘外侧炎（RLE）的患者，并随机分为PRP组（关节镜下ECRB修复后进行一次PRP注射；n=40）和对照组（单独行关节镜下ECRB修复；n=40）。磁共振成像分别在术后3个月、6个月和12个月时评估肌腱愈合。术前及随访期间对疼痛视觉模拟量表（VAS）、Mayo肘部功能评分（MEPS）、肩肘腕残疾问卷（DASH）、网球肘患者自评量表（PRTEE）得分、关节活动范围以及肌肉力量进行评价。还比较了两组患者的返工时间。研究者和评估人员均对干预措施进行了盲法处理。

结果： 共有80名符合纳入标准的患者于2020年7月至2023年7月期间入组，其中73名完成随访。PRP组包括35例患者（11名男性和24名女性），平均年龄为47.8±8.8岁；对照组包括38例患者（13名男性和25名女性），平均年龄为44.5±5.8岁。术前及随访期间，两组在磁共振成像分类和功能评分方面没有显著差异。两个研究组均显示出VAS、MEPS、DASH和PRTEE得分以及肌肉力量在术后12个月有显著改善（P

结论： 在12个月的随访中，作为ECRB修复辅助治疗使用的PRP在肌腱愈合及功能结果上并未表现出比单独进行ECRB修复更优的效果。然而，在术后6周时，PRP治疗组与单独进行ECRB修复相比显示了肌肉力量方面的差异。

注册： NCT04556825（ClinicalTrials.gov）。

关键词： ECRB；关节镜；富含血小板的血浆（PRP）；顽固性肘外侧炎；肌腱修复。