Proximal Hamstring Tendon Avulsions: A Retrospective Study

Proximal hamstring tendon avulsions are a relatively common injury, occurring in both high level and recreational athletes. These injuries occur due to an eccentric load while the knee is extended, and hip is flexed. Management of proximal hamstring injuries is a current area of controversy. The literature has shown improved strength and return to pre-injury level of activity with surgical repair of these injuries, unfortunately this has been shown to be associated with complication rates of up to 23%. The aim of this study was to explore the clinical results following operative management of proximal hamstring tendon avulsions, in addition to assessing patient outcomes after surgical repair of these injuries. This was a single-site retrospective study of patients with surgically repaired proximal hamstring tendon avulsions between 2017 and 2022, with at least one year follow up. Patient demographics, mechanism of injury, surgical data and complications were collected. Patient strength was assessed by prone knee flexion compared to the contralateral normal side. Patient reported outcomes were also performed which included the Lower Extremity Function (LEF) score and International Hip Outcome Tool (iHOT) score at final follow up. The collected data was analyzed and P values of < 0 .05 were considered statistically significant. A total of 41 patients were included in the study with a mean age of 49.5±11.7 years. Of the cohort 58.5% were males with the most common mechanism of injury being skating/skiing (31.7%). A three-tendon injury was the most common entity (82.9%) and the majority were retracted at least 6cm (51.2%). A significant association was found between number of tendons injured and patient age, as single tendon injury mean age (30.7±13.4) was significantly younger than two and three tendon injuries (49±18.5 and 51.2±9.4, respectively, p < 0 .05). Concerning operative data, median time from injury to surgery was 22 days (IQR 16.5 to 35, range 7-153 days). Nearly all cases were fixed with suture anchors (95.1%) and three anchors was the most common number applied (46.2%). Of the cohort 12.2% had a complication (two of which were nerve injuries (neuropathic pain from posterior femoral cutaneous nerve), two were failure of repair and one was intractable pain requiring admission for pain control). The majority of patients regained full hamstring strength (87.8%) and returned to pre-injury activity levels (70.7%). Patient reported outcomes post-repair were excellent at final follow up, as mean LEFS was 93.6±15.9 and mean iHOT was 92.2±17.4. Patient reported outcomes were significantly associated with complications, return of full hamstring strength, return to baseline level of activity and patient satisfaction. Patients who have their proximal hamstring tendon avulsions repaired surgically can expect to regain pre-injury strength and level of activity with good patient reported outcomes and low rates of complications.