Acute Proximal Hamstring Ruptures
The hamstring muscles are the most commonly strained muscles in the body and account for 25% to 30% of all muscle strains. While the majority of hamstring injuries occur at the myotendinous junction and respond well to nonoperative treatment modalities, as many as 12% of injuries may involve a tear or avulsion of the proximal hamstring’s origin, and 9% may be complete avulsions. The frequency of acute hamstring ruptures appears to be increasing as middle-aged patients continue to be physically active and as the recognition and potential for treatment have become better established.
Our understanding of the natural history of complete proximal hamstring ruptures has been informed by a limited number of case series with small numbers of patients under-going nonoperative management. Albeit limited, the available evidence suggests that a complete rupture of all 3 tendons has been associated with persistent pain, decreased function, prolonged time away from sports, and appreciable weakness. Sallay demonstrated that of 12 patients who underwent initial nonoperative treatment, 7 patients returned to most of their preinjury sports at a lower level. Of these 7 patients, 6 had a partial tear of the proximal hamstring complex. Of the 5 patients who had complete disruption of the hamstring tendons, all 5 patients were unable to run or participate in sports requiring agility.
Surgical Repair of Proximal Hamstring Rupture
There is some evidence in the form of retrospective case series that suggests that surgical repair of proximal hamstring avulsions results in good pain relief, return to sports, and high patient satisfaction. A systematic review of 18 studies and 298 patients with proximal hamstring avulsions demonstrated that 82% of patients (236/298) were able to return to sports at pre-injury levels after surgical treatment. Data pertaining to the 14 patients who had under- gone nonoperative treatment were abstracted from 3 of the 18 included studies. Of these 14 patients, 2 patients (14%) were able to return to sports at pre-injury levels at final follow-up. With respect to surgical management, repair within 4 weeks of injury resulted in significantly better patient satisfaction and a higher rate of return to a pre-injury level of sport compared with after 4 weeks of injury.
The majority of studies that have looked at outcomes after operative and nonoperative treatments of proximal hamstring injuries have reported nonvalidated, subjective clinical variables such as pain relief, return to sport, patient satisfaction, responses to study-specific subjective questionnaires (excellent, good, fair, poor), as well as isokinetic strength testing.11 Although no instruments have been tested for reliability, validity, or responsiveness in patients with proximal hamstring avulsions, the use of joint-specific or global lower extremity functional scales to assess outcomes has also been limited. The use of magnetic resonance imaging (MRI) to assess healing, as well as hamstring muscle and attachment characteristics, has been reported in one previous series with 6 patients.
Outcomes of Proximal Hamstring Surgical Repair
The objective of this study was to comprehensively evaluate clinical, functional, and radiological outcomes in a cohort of consecutive patients treated with surgical repair for complete proximal hamstring avulsion injuries. We hypothesized that patients undergoing surgical repair of complete proximal hamstring avulsions would have excellent functional outcomes, high patient satisfaction, and a high proportion of healed repairs as per postoperative MRI.