At mid- to long-term follow-up after proximal hamstring tendon avulsion; there was greater fatty infiltration, muscle atrophy and strength deficit in the hamstring muscles of the injured leg than in the uninjured leg.

BACKGROUND: Proximal hamstring tendon avulsions (PHAs) may be treated nonoperatively or operatively. Little is known about the result of the injury, and its treatment, on the quality and function of the hamstring muscle after healing and rehabilitation. We hypothesized that the injured leg would have greater fatty infiltration and atrophy than the uninjured leg at follow-up and that these findings would correlate to muscle weakness. METHODS: In a cross-sectional cohort study, 48 patients treated for PHA, either operatively or nonoperatively, were re-examined 2-11 years post-treatment. We measured muscle strength with isokinetic strength tests, and muscle volume and fatty infiltration with MRI. Primary outcomes were hamstring muscle quality, quantified by outlining the cross-sectional area slice-by-slice, and the degree of fatty infiltration estimated using the Goutallier grading method. Secondary outcome was concentric isokinetic hamstring muscle strength measured using BioDex at 60°/sec and tendon attachment assessed on MRI. Comparisons with the outcomes of the uninjured leg were made. RESULTS: The total hamstring muscle volume was on average reduced by 9% (SD ± 11%, p < 0.001) compared to that of the uninjured leg. Fatty infiltration was significantly more severe in the injured hamstrings than in the uninjured hamstrings (p < 0.001). This was also true when only analyzing operatively treated patients. The reduction in muscle volume and increase in fatty infiltration correlated significantly (r = 0.357, p = 0.013), and there was also a statistically significant correlation with muscle atrophy and reduction in isokinetic strength (r = 494, p < 0.001). CONCLUSION: PHA injuries result in fatty infiltration and muscle atrophy and the muscle quality impairment correlates with residual muscle weakness.

Proximal Hamstring Tendon Avulsions: A Survey of Orthopaedic Surgeons' Current Practices in the Nordic Countries.

BACKGROUND AND PURPOSE: Evidence guiding the decision on whether to treat proximal hamstring tendon avulsions (PHA) operatively or non-operatively is very limited. The aim of this study was to identify the current practices and the rationale behind PHA treatment decisions in the Nordic countries. METHODS: A survey was sent to orthopaedic surgeons in Sweden, Norway, Finland and Denmark. The study population consisted of responding surgeons with exposure to surgical treatment of PHA (n = 125). The questions covered surgeon and unit characteristics, and surgeons' understanding of the evidence for treatment, and they explored which patient and injury factors influence treatment allocation. RESULTS: Although some surgeons indicated a preference for one of the treatments, 84% stated that the treatment decision was based on patient and injury-related factors. Severe obesity, drug abuse, a sedentary lifestyle, age > 60 years and delayed diagnosis (> 6 weeks) were considered contraindications to surgical treatment. Also, there was agreement that patients expressing a preference for non-operative treatment should not be operated. Complete avulsions with tendon dislocation ≥ 2-3 cm on MRI were relative indications for surgical treatment. The majority of surgeons did not believe that operatively treated patients did better than non-operatively treated patients and experienced that patients, generally, were satisfied with the treatment result, regardless of the type of treatment. Most surgeons had experienced significant complications to operative treatment. CONCLUSION: Current practices varied among different units, and despite the lack of evidence for their prognostic value, several factors were inconsistently being used as decision modifiers when selecting patients for surgical treatment.

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.

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.

INTRODUCTION: The 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 ANALYSIS: PHACT 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 DISSEMINATION: Ethical 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 NUMBER: NCT03311997.

Patient-reported outcomes after surgical and non-surgical treatment of proximal hamstring avulsions in middle-aged patients.

OBJECTIVES: In the literature on proximal hamstring avulsions, only two studies report the outcomes of non-surgically treated patients. Our objective was to compare subjective recovery after surgical and non-surgical treatment of proximal hamstring avulsions in a middle-aged cohort. METHODS: We included 47 patients (33 surgically and 14 non-surgically treated) with a mean (SD) age of 51 (±9) years in a retrospective cohort study. Follow-up time mean (SD) of 3.9 (±1.4) years. The outcome variables were the Lower Extremity Functional Scale (LEFS) and questions from the Proximal Hamstring Injury Questionnaire. Outcome variables were adjusted in regression models for gender, age, American Society of Anestesiologits (ASA) classification and MRI findings at diagnosis. RESULTS: The baseline characteristics showed no differences except for the MRI result, in which the surgically treated group had a larger proportion of tendons retracted ≥ 2 cm. The mean LEFS score was 74 (SD±12) in the surgically treated cohort and 72 (SD±16) in the non-surgically treated cohort. This was also true after adjusting for confounders. The only difference in outcome at follow-up was the total hours performing physical activity per week, p=0.02; surgically treated patients reported 2.5 hours or more (5.2 vs 2.7). CONCLUSION: This study on middle-aged patients with proximal hamstring avulsions was unable to identify any difference in patient-reported outcome measures between surgically and non-surgically treated patients. The vast majority of patients treated surgically had complete proximal hamstring avulsions with ≥ 2 cm of retraction. We conclude that to obtain an evidence-based treatment algorithm for proximal hamstring avulsions studies of higher scientific level are needed.