Predictive Factors Influencing Functional Results After Proximal Hamstring Tendon Avulsion Surgery: A Patient-Reported Outcome Study After 227 Operations From a Single Center

Abstract

Background: Although debilitating, proximal hamstring tendon avulsion injuries are rare and often overlooked or misdiagnosed. Consequently, delayed diagnosis and surgical treatment may result in poor outcomes. Studies investigating a correlation between postoperative functional outcomes and this delay in surgical treatment or other concomitant factors in large cohorts have not yet been performed to our knowledge. Purpose/Hypothesis: The purpose of this study was to conduct an investigation in a large patient group regarding factors that could influence a patient’s functional outcome after hamstring surgery. We hypothesized that this outcome would significantly correlate to the time between trauma and surgery. Study Design: Case series; Level of evidence, 4. Methods: Patients who received surgical treatment of proximal hamstring tendon avulsion injuries in our institution between the years 2010 and 2020 were asked to complete a validated, injury-specific outcome measurement, the Perth Hamstring Assessment Tool (PHAT; 0-100 points). In addition to calculating these outcomes, we evaluated the association of the obtained results with possible predictive factors such as age, sex, stump retraction shown on magnetic resonance imaging (MRI), and timing and duration of surgery. Results: A total of 226 patients (227 operations) were eligible for the study, and 204 cases of hamstring tendon avulsion injury met our inclusion criteria. The return rate for the PHAT questionnaire was 85.3%. The mean PHAT score revealed good results (79.8 ± 19.1). Irrespective of concomitant factors, the scores of male patients were significantly higher compared with those of female patients (83.8 ± 16.9 vs 75.8 ± 20.6 respectively; P = .004). The mean time to surgery was 5.7 weeks after trauma, and more delayed surgery correlated significantly with lower PHAT scores ( P = .003; r = –0.228). The mean degree of stump retraction on MRI (5 cm) did not significantly influence PHAT scores ( P = .525; r = –0.06). Conclusion: Delay of surgery and female sex were disadvantageous in terms of a good functional outcome measure (PHAT score) after hamstring tendon refixation surgery. By contrast, patient age as well as the retraction of the tendon stump on preoperative MRI did not influence PHAT scores in the present study.

Modified surgical anchor refixation in older patients with acute proximal hamstring rupture: clinical outcome, patient satisfaction and muscle strength

“…The subjective satisfaction rate in our patients was extremely high and comparable to non-modified hamstring refixation (98.8 vs. 97% [19]). Similarly, the PHAT score was comparable to what was reported for patients after other surgical refixation methods (78.8 vs. 74.1 [41], 79.8 [42] and 79.9 [43]). The questions with the lowest points in the PHAT were number of minutes without discomfort while driving a car, number of minutes without discomfort while running and description of the current level of activity.…”

Comparative Analysis of Patient-Reported Outcome Measures for Proximal Hamstring Injuries: A Systematic Review

“… 16 Additionally, the PHAT is the most frequently used of these proximal hamstring–specific PROMs in the literature (6/34 included studies) and has been gaining recognition as the preferred PROM for proximal hamstring injury studies. 2 , 3 , 7 , 8 , 26 , 27 , 33 In conjunction with these findings, the PHAT had the greatest proportion of unique questions compared with the other proximal hamstring–specific PROMs in this study. These unique questions incorporate a visual analog scale to evaluate pain “at rest” and “with stride-out stretch” as well as categorical scores for activity levels, such as the maximum time for “driving a car.” 8 Moreover, the PHAT contextualizes common symptoms and characterizes the potential sequelae of proximal hamstring injuries, such as gluteal pain and sitting intolerance, more comprehensively than the questions in the SHORE.…”

Association Between Proximal Hamstring Tear Characteristics and Achievement of Clinically Significant Outcomes After Endoscopic and Open Repair at Minimum 2-Year Follow-up

“…Bowman et al 8 reported a similar conclusion based on 45 patients at a minimum 1-year follow-up, as they were unable to detect any significant difference in outcome scores between tear grades. Likewise, in 204 full-thickness tears, Best et al 6 reported that the amount of stump retraction (>5 cm) did not significantly influence outcome scores at short-term follow-up. However, Barnett et al 5 reported after analyzing their cohort of 132 patients that those with complete tears and acute surgical treatment were more likely to have a good or excellent result than those with partial-thickness tears at a 2-year follow-up.…”

“…Furthermore, there are limited and inconsistent data on the effect of preoperative patient factors and tendon characteristics, such as tear size and tendon retraction, on postoperative outcomes to help guide the approach for the treatment of different tears. 5,6,8,21,35 Moreover, the relative indications for open and endoscopic repair have yet to be elucidated, and the literature does not clearly support one over the other in most outcomes. 2 The purposes of this study were to (1) report on achievement rates of clinically significant outcomes at a minimum 2-year follow-up for multiple patient-reported outcomes (PROs) after surgical treatment of proximal hamstring injuries, stratified according to severity of proximal hamstring injury, and (2) report on how tear characteristics are associated with PROs and the achievement of clinically significant outcomes after endoscopic and open surgical repair.…”

“…Furthermore, there are limited and inconsistent data on the effect of preoperative patient factors and tendon characteristics, such as tear size and tendon retraction, on postoperative outcomes to help guide the approach for the treatment of different tears. 5,6,8,21,35 Moreover, the relative indications for open and endoscopic repair have yet to be elucidated, and the literature does not clearly support one over the other in most outcomes. 2…”