Incidence of Symptomatic Venous Thromboembolism in Proximal Hamstring Repair: A Prospective Cohort Study

Background: Surgical repair of proximal hamstring avulsion injuries can enable the return to preinjury levels of sporting function and minimize the risk of recurrence in both professional and recreational athletes. While venous thromboembolism (VTE) is a recognized complication of surgical repair, the incidence thereof is poorly reported in the literature. Purpose/Hypothesis: To report the incidence of symptomatic VTE after proximal hamstring avulsion repair and assess the efficacy of our thromboprophylaxis protocol. It was hypothesized that the incidence of VTE after proximal hamstring avulsion repair is low and that aspirin is an adequate choice of chemical prophylaxis. Study Design: Cohort study; Level of evidence, 2. Methods: We performed a prospective cohort study of 2 groups of patients who underwent proximal hamstring avulsion (partial and complete) repair between 2000 to 2020 with different thromboprophylaxis protocols. No patients were routinely screened for VTEs, and VTE was investigated only if clinically indicated. Prospectively collected data included demographics, the mechanism and sport that caused injury, use of bracing, and clinical diagnosis of deep vein thrombosis (DVT) or pulmonary embolism (PE). The first cohort (n = 380) was given mechanical prophylaxis in the form of compression stockings for 6 weeks postoperatively. The second cohort (n = 600) was given compression stockings and aspirin 150 mg once daily routinely, or prophylactic low–molecular weight heparin in high-risk individuals, until the 6-week follow-up. Patients in both cohorts underwent early mobilization after surgery; a hinged knee brace locked at 60° to 120° was provided if the tendon repair was under significant tension. The surgical technique and rehabilitation protocol remained consistent throughout the study. Results: The overall incidence of symptomatic VTE was 0.51%. A total of 5 patients developed symptomatic VTEs (3 DVTs, 2 PEs) in the first cohort, and no patients developed symptomatic VTEs in the second cohort (1.32% vs 0%; P = .0048). Conclusion: The incidence of symptomatic VTE after proximal hamstring avulsion repairs was extremely low. A combination of aspirin, early mobilization despite bracing, compression stockings, and good hydration was an effective thromboprophylaxis strategy.

Exploring the Perth Hamstring Assessment Tool and Lower Extremity Functional Scale in a Proximal Hamstring Avulsion Cohort: A Cross-sectional Study

Background: The goal of treatment for a proximal hamstring avulsion (PHA) is an objectively restored muscle and a subjectively satisfied, pain-free patient at follow-up. Different self-reported and performance-based outcome measures have been used to evaluate recovery, but their validity is poorly investigated. Purpose: To investigate 1) the correlation between the commonly used self-reported outcome measurements, the Perth Hamstring Assessment Tool (PHAT) and the Lower Extremity Functional Scale (LEFS); 2) to what extent these scores can be explained by physical dysfunction as measured by performance-based tests; 3) whether performance-based tests can discriminate between the injured and uninjured extremity; and 4) which activity limitations are perceived by patients several years after the injury. Study design: Cohort study (Diagnosis); Level of evidence, 3. Methods: We included a consecutive series of patients treated for or diagnosed with PHA in our department between 2007 and 2016 having at least 2 tendons avulsed from the ischial tuberosity. Participants attended 2 study visits, answered questionnaires (PHAT, LEFS, and Patient-Specific Functional Scale [PSFS]), and performed physical performance–based tests (single-leg hop tests, single–step down test, and isometric and isokinetic strength tests). Results: A total of 50 patients were included (26 men [52%], 24 women [48%]; mean age, 50.9 years [SD, 9.8 years]). The mean follow-up time was 5.5 years (SD, 2.7 years), and 74% had been surgically treated. The correlation between PHAT and LEFS was strong ( r = 0.832) and statistically significant ( P < .001). Seven of the performance-based tests exhibited a statistically significant but weak correlation with LEFS (0.340-0.488) and 3 of the tests to PHAT (–0.304 to 0.406). However, only peak torque could significantly discriminate between the extremities. The activity limitation most commonly mentioned in PSFS was running (16 patients [32%]). Conclusion: Although PHAT and LEFS correlated strongly, the correlations between functional tests and the patient-reported outcome scores were weak, and most functional tests failed to discriminate between the injured and uninjured lower extremity in patients with PHA 5 years after injury. In general, patients alleged few activity limitations, but running difficulty was a common sequela after PHA.

Surgical Management of Chronic Incomplete Proximal Hamstring Avulsion Injuries

Background: Chronic incomplete proximal hamstring avulsion injuries are debilitating injuries associated with prolonged periods of convalescence and poor return to preinjury level of function. This study explores the efficacy of operative intervention for these injuries on patient satisfaction, muscle strength, range of motion, functional performance, return to preinjury level of sporting activity, and injury recurrence. Hypothesis: Surgical intervention of chronic incomplete proximal hamstring avulsion injuries enables return to preinjury level of sporting function with low risk of clinical recurrence. Study Design: Case series: Level of evidence, 4. Methods: This prospective single-surgeon study included 41 patients with incomplete proximal hamstring avulsion injuries refractory to 6 months of nonoperative treatment. All study patients underwent primary operative repair of the avulsed proximal hamstring tendon and received standardized postoperative rehabilitation. Predefined outcomes were recorded at regular intervals after surgery. Mean follow-up time was 28.2 months (range, 25.0-35.0 months) from date of surgery. Results: All patients returned to their preinjury level of sporting activity. Mean ± SD time from surgery to return to full sporting activity was 22.2 ± 6.7 weeks. There were no episodes of clinical recurrence. At 3 months after surgery, 39 patients (95.1%) were satisfied/very satisfied with the outcomes of their surgery, and as compared with preoperative values, improvements were recorded in isometric hamstring muscle strength at 0° (84.9% ± 10.9% vs 40.4% ± 8.8%; P < .001), 15° (89.6% ± 7.6% vs 44.2% ± 11.1%; P < .001), and 45° (94.1% ± 5.1% vs 66.4% ± 9.0%; P < .001); mean passive straight leg raise angle (71.2°± 13.5° vs 45.4°± 11.9°; P < .001); mean lower extremity functional score (70.9 ± 5.1 vs 48.4 ± 5.2; P < .001); and mean Marx activity rating score (5.6 ± 2.8 vs 2.7 ± 1.0; P < .001). High patient satisfaction and functional outcome scores were maintained at 1- and 2-year follow-up. Conclusion: Operative repair of chronic incomplete proximal hamstring avulsion injuries enabled return to preoperative level of sporting function with no episodes of clinical recurrence at short-term follow-up. Surgical intervention was associated with high patient satisfaction and improved isometric hamstring muscle strength, range of motion, and functional outcome scores as compared with preoperative values. High patient satisfaction and improved functional outcomes were sustained at 2-year follow-up.

Suture Bridge Repair of Proximal Hamstring Avulsion: A Case Report

Proximal hamstring avulsion injuries can represent a challenging problem and lead to severe patient morbidity if not treated appropriately. The most common method for acute surgical fixation involves the use of between two and five suture anchors in a variety of configurations. The five-anchor fixation has become the gold standard due to the increased biomechanical stability. However, the technique has also been criticized due to the need for greater exposure and technical difficulty. We report on an individual with a proximal hamstring avulsion injury who was managed with a modified approach, utilizing only three anchors in a suture bridge technique. The patient had good clinical outcomes at their 3-month follow-up visit, demonstrating this technique to be a viable option that is less technically demanding.

The proximal hamstring avulsion clinical trial (PHACT)—a randomised controlled non-inferiority trial of operative versus non-operative treatment of proximal hamstrings avulsions: study protocol

IntroductionThe treatment of proximal hamstring avulsions is controversial. While several trials have investigated the outcome for patients treated surgically, there is today no prospective trial comparing operative treatment with non-operative treatment. This protocol describes the design for the proximal hamstring avulsion clinical trial (PHACT)—the first randomised controlled trial of operative versus non-operative treatment for proximal hamstring avulsions.Methods and analysisPHACT is a multicentre randomised controlled trial conducted across Sweden, Norway and Finland. Eligible patients (60 participants/treatment arm) with a proximal hamstring avulsion of at least two of three tendons will be randomised to either operative or non-operative treatment. Participants allocated to surgery will undergo reinsertion of the tendons with suture anchors. The rehabilitation programme will be the same for both treatment groups. When patient or surgeon equipoise for treatment alternatives cannot be reached and randomisation therefore is not possible, patients will be invited to participate in a parallel observational non-randomised cohort. The primary outcome will be the patient-reported outcome measure Perth hamstring assessment tool at 24 months. Secondary outcomes include the Lower Extremity Functional Score, physical performance and muscle strength tests, patient satisfaction and MR imaging. Data analysis will be blinded and intention-to-treat analysis will be preformed.Ethics and disseminationEthical approval has been granted by the Ethical Committee of Uppsala University (DNR: 2017–170) and by the Norwegian ethical board (REC: 2017/1911). The study will be conducted in agreement with the Helsinki declaration. The findings will be disseminated in peer-reviewed publications.Trial registration numberNCT03311997

A combined endoscopic and open surgical approach for chronic retracted proximal hamstring avulsion

Proximal hamstring avulsion is an uncommon injury which usually requires surgical intervention. When possible, primary surgical fixation is recommended. In chronic hamstring avulsion with significant retraction of the tendon, hamstring reconstructions using an autograft or allograft are required in order to bridge the gap. This is mainly performed using an open surgical technique. We describe a combined endoscopic and open surgical approach to hamstring reconstruction surgery.