Inferior Clinical Outcomes Following Endoscopic Proximal Hamstring Repair in Patients with Chronic Degenerative Tears Despite the use of Dermal Allograft Augmentation.

Purpose: To compare clinical outcomes in patients undergoing endoscopic proximal hamstring repair with and without dermal allograft augmentation.

Methods: A retrospective review of prospectively collected data was performed on patients undergoing endoscopic proximal hamstring repair (PHR) and proximal hamstring repair with dermal allograft augmentation (PHR-A) by a single surgeon between 2016 and 2023. Augmentation was utilized for cases of chronic degenerative tears (> 6 weeks from the time of initial injury) where hamstring tissue quality was deemed poor intraoperatively. A survey of patient-reported outcome measures (PROMs) was completed at a minimum of 1 year postoperatively. PROMs included a Visual Analogue Scale (VAS) for pain; University of California, Los Angeles (UCLA) Activity Scale; modified Harris Hip Score (mHHS); Hip Outcome Score-Sports-Specific Subscale (HOS-SSS); and a Single Assessment Numeric Evaluation (SANE). The proportion of patients achieving the minimal clinically important difference (MCID), patient acceptable symptom state (PASS), and substantial clinical benefit (SCB) for PROMs were compared between groups.

Results: Sixty-four patients were included (42 PHR, 22 PHR-A). No differences were seen between the PHR and PHR-A groups in terms of age at surgery (49 ± 12 vs. 54 ± 9, p=0.08), sex, or body-mass index (BMI). There was a significantly longer time to follow-up (41.5±23.4 vs. 20.1±10.2 months, p<0.001) in the PHR group. There were significantly greater postoperative mHHS (82.7±15.1 vs. 72.0±18.0, p=0.02) and SANE (89.6±9.9 vs. 73.6±22.5, p=0.002) scores in the PHR group. There were no significant differences in postoperative VAS, UCLA, or HOS-SSS between groups. A greater proportion of patients in the PHR group achieved a SCB for mHHS (71% vs. 36%, p=0.008).

Conclusions: Our study demonstrates inferior clinical outcomes in patients undergoing endoscopic proximal hamstring repair with dermal allograft augmentation compared to patients undergoing endoscopic proximal hamstring repair without augmentation.

Level of evidence: III, retrospective comparative case series.