Returning to sports after surgical repair of acute proximal hamstring ruptures

Magnetic resonance imaging should be the first-line imaging modality for investigating suspected proximal hamstring avulsion injuries

PURPOSE

The purpose of the study was to evaluate how the initial diagnostic tool used-specifically ultrasound (US) or magnetic resonance imaging (MRI)-for diagnosing proximal hamstring avulsion injury affects the delay before surgery and, secondarily, the outcomes of these injuries.

METHODS

This was a retrospective analysis of prospectively collected data (2012-2020). It targeted patients primarily treated for proximal hamstring avulsion injury. It included all patients with a preoperative US and/or MRI. Patients were divided into two groups based on the initial diagnostic tool used (US-first vs. MRI-first groups). The primary outcomes measure was the time from initial injury to surgical intervention (surgical delay). The secondary outcomes were the Parisien Hamstring Avulsion Score, as well as the activity level as measured by the University of California, Los Angeles (UCLA) Activity Scale and Tegner Activity Scale.

RESULTS

The analysis included 392 patients with a mean age of 43.8 ± 13.6 years for the MRI-first group and 47.6 ± 12.0 years for US-first group. Patients in the MRI-first group had a significantly shorter median time from injury to surgery of 20.0 days (interquartile range [IQR]: 11.0-61.0) compared to 30 days (IQR: 18-74) in the US-first group. At the final follow-up (4.2 ± 2.2 years for the MRI-first group and 5.1 ± 1.9 years for the US-first group), the MRI-first group had significantly higher mean Tegner Activity Scale and UCLA scores than the US-first group: The Tegner Activity Scale was median 5 (IQR: 3-7) for the MRI-first group versus median 4 (IQR: 2-6) for the US-first group (p < 0.05). The UCLA scores were 7.9 ± 2.4 for the MRI-first group compared to 7.3 ± 2.4 for the US-first group (p < 0.05). This difference was more pronounced when comparing the MRI-first group with the patient-false negative initial ultrasound. No difference was found regarding the Parisien Hamstring Avulsion Score.

CONCLUSION

MRI as the initial diagnostic tool for proximal hamstring avulsion injury is associated with a shorter time to surgery and better postoperative outcomes in Tegner Activity Scale and UCLA scores, compared to US.

LEVEL OF EVIDENCE

Level III.

Validation of the Parisian Hamstring Avulsion Score (PHAS) in the Evaluation and Follow-up of Patients Operated for Proximal Hamstring Avulsion

BACKGROUND

No validated score is available for the prediction of return to sport (RTS) after proximal hamstring avulsion (PHA) surgery.

PURPOSE

To validate a new assessment tool for patients after PHA surgery: the Parisian Hamstring Avulsion Score (PHAS).

STUDY DESIGN

Cohort study (Diagnosis); Level of evidence, 3.

METHODS

All patients at our clinic who had surgery for PHA between January 2015 and March 2018 were included in this study. A suspected clinical diagnosis of PHA was confirmed by magnetic resonance imaging. PHA was repaired by surgical reinsertion with suture anchors. Minimum postoperative follow-up was 2 years, and the PHAS, University of California, Los Angeles (UCLA), score, and Tegner score were used. The PHAS is a patient-reported outcome measure, evaluating the effect of PHA injury with 9 items. It was validated by calculating its psychometric properties, and then correlation analysis was performed to determine the relationship between the PHAS, UCLA score, and Tegner score. Cutoff values for the prediction of RTS were determined.

RESULTS

A prospective case series study was performed. A total of 156 patients were included. Median age (first quartile; third quartile) was 54.2 years (44.7 years; 61.3 years), and the mean ± SD time of the final follow-up was 69 ± 11.6 months. Two years after surgery, 66.7% (n = 104) of patients were able to RTS. A strong correlation was noted between all 3 scores at 1 year postoperatively. Overall internal consistency was high, with a Cronbach alpha coefficient of 0.86. The intraclass correlation coefficient was 0.96, showing excellent reliability. The minimal detectable change was 12.9. No patients reached the maximum score at 2 years. Analysis of the receiver operating characteristic curves of the 3 scores at postoperative 9 months in relation to the RTS at 1 and 2 years showed area under the curve values of >0.7, indicating significant discriminant capacity for the RTS. A PHAS cutoff value of 86 at 9 months for the prediction of RTS at postoperative 1 year had a sensitivity of 65.6% (95% CI, 53.7%-77.5%) and a specificity of 81.4% (95% CI, 69.8%-93%).

CONCLUSION

PHAS is a valid and reliable tool for follow-up after PHA surgery. It also offers a simple way to predict RTS.

Predictors of Early Return to Sport After Surgical Repair of Proximal Hamstring Complex Injuries in Professional Athletes: A Prospective Study

BACKGROUND

Proximal hamstring complex injury (PHCI) is a common injury among professional athletes, particularly those participating in pivot contact sports. Previous studies have suggested that surgery can be effective in restoring function and allowing athletes to return to sport (RTS), but the factors influencing successful RTS have been less clear.

PURPOSE

To assess RTS capabilities after surgical treatment of PHCI in professional athletes and to identify favorable predictors of RTS.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

This study (2002-2022) was conducted on professional athletes who underwent surgical treatment for PHCI at a sports surgery center. The primary outcome of the study was the RTS capability, evaluated based on the rate of athletes' return to their preinjury level of competition, time delay to RTS, and quality of RTS as measured using their level of performance and progression of scores on activity scales such as the Tegner Activity Scale (TAS) and University of California, Los Angeles (UCLA), scale. "Maintained performance" was defined as athletes returning to the same preinjury activity level (per the TAS and UCLA scale) and perceiving themselves to have maintained their performance. Secondary outcomes covered the potential RTS predictors and complication rate. The study distinguished 2 types of PHCI: proximal hamstring tendon avulsion injury (proximal rupture with empty footprint, or having a "positive dropped ice cream sign") and complete proximal hamstring free tendon rupture (PHTR; proximal rupture without empty footprint, or having a "negative dropped ice cream sign").

RESULTS

The study examined 64 professional athletes (mean age, 27.3 years; 82.8% male) undergoing surgery for PHCI. The RTS rate was 98.4%, with 78.1% of the athletes returning to their preinjury level of competition at 6.2 months (SD, 2.5 months). Twelve (19%) patients had returned to sport at an inferior level of competition, and 2 (3.1%) were unable to continue in their preinjury sport. Subgroup analysis revealed variation in RTS based on sport type, with the highest rate of return to preinjury performance found in athletes in handball and sports with splits (fencing, squash, and escalade; 100%) and soccer (95.2%). In the univariate analysis, male sex (hazard ratio [HR], 4.05; 95% CI, 1.45-11.3; P = .008), higher preinjury TAS score (HR, 1.27; 95% CI, 1.06-1.52; P = .011), injury involving the semimembranosus (HR, 4.84; 95% CI, 2.31-10.2; P < .001) or conjoint tendon (HR, 3.12; 95% CI, 1.55-6.25; P = .001), and PHTR (HR, 7.77; 95% CI, 3.54-17.0; P < .001) were significantly associated with a better postoperative level of competition. Multivariate analysis identified 3 favorable predictors of RTS with HRs of 2.91 (95% CI, 1.01-8.35; P = .047) for male sex, 3.86 (95% CI, 1.78-8.37; P < .001) for isolated semimembranosus injury, and 5.18 (95% CI, 2.24-12.0; P < .001) for PHTR. The complication rate was 4.7%.

CONCLUSION

Favorable predictors of early RTS were male sex, isolated semimembranosus injury, and PHTR injuries.

REGISTRATION

NCT02906865 (ClinicalTrials.gov identifier).

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

BACKGROUND

The effect of preoperative tear characteristics and the relative efficacy of open versus endoscopic surgical techniques have not been elucidated for the surgical treatment of proximal hamstring tendon injuries.

PURPOSE

(1) To 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) to compare clinical outcomes associated with endoscopic versus open surgical repair for a subset of similarly classified tears.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

A single-surgeon clinical registry was queried for patients who underwent surgical repair for proximal hamstring ruptures between January 2012 and March 2021. Injuries were classified by magnetic resonance imaging as follows: grade 1, incomplete tear with the involvement of 1 or 2 tendons; grade 2, complete tear with the involvement of 3 tendons and ≤2-cm retraction; and grade 3, complete tear with the involvement of 3 tendons and >2-cm retraction. The Patient Acceptable Symptom State (PASS) for multiple PROs was calculated and compared among injury grades and between surgical techniques.

RESULTS

Among 75 patients with a mean follow-up of 30.5 ± 5.1 months, 20 had grade 1 tears, 24 had grade 2 tears, and 31 had grade 3 tears. Favorable 2-year postoperative PROs were demonstrated by each grade for all measured PROs. Patients with grade 3 tears were noted to have significantly lower rates of 2-year PASS achievement for the Hip Outcome Score-Activities of Daily Living (HOS-ADL) and Hip Outcome Score-Sports Specific (HOS-SS) scales (P≤ .032). Among grade 2 tears, patients treated endoscopically demonstrated significantly greater HOS-SS (endoscopic, 91.7%; open, 58.3%; P = .045) and Patient-Reported Outcomes Measurement Information System for Physical Function (endoscopic, 80.0%; open, 50.0%; P = .033) PASS achievement rates compared with those treated with the open technique. Complication rates were highest in patients with grade 3 tears (45.2%, P = .043).

CONCLUSION

Surgical repair of proximal hamstring tendon tears with varying extents of tendon retraction resulted in high rates of achieving PASS at the 2-year follow-up. Among complete tears with <2 cm of retraction, endoscopic repairs exhibited equal or higher rates of achieving PASS compared with open repairs across multiple PROs at 2 years postoperatively. However, patients with complete tears and retraction >2 cm achieved lower rates of PASS on the HOS-ADL and HOS-SS scales and had a higher rate of complications.

Development and application of a proximal hamstring MRI-based scoring tool in patients undergoing proximal hamstring tendon surgical repair

Purpose

An MRI-based scoring tool assessing surgical repair after proximal hamstring avulsions may provide benefit in the context of research, while serial post-operative MRI will provide insight of what to expect in the clinical context of early re-injury requiring imaging. This study developed and assessed the reliability of a Proximal Hamstring Objective Magnetic Resonance Imaging Score (PHOMRIS), further assessing MRI-based repair status and its correlation with patient-reported outcome.

Methods

15 patients that underwent proximal hamstring surgical repair underwent MRI and clinical review pre-operatively and at 3-, 6- and 12-months. Clinical scores included the Lower Extremity Functional Scale (LEFS), the Perth Hamstring Assessment Tool (PHAT) and Tegner Activity Scale (TAS). The MRI-based tool assessed the conjoint (semitendinosus & biceps femoris) and semimembranosus insertion components based on bone-tendon healing, signal and retraction. Inter- and intra-observer reliability of the tool was assessed.

Results

Inter-observer reliability indicated a strong correlation for the semimembranosus (rho = 0.827, p < 0.0001) and conjoint (rho = 0.851, p < 0.0001) components. Intra-observer reliability indicated a strong correlation for the semimembranosus (rho = 0.852, p < 0.0001) and conjoint (rho = 0.996, p < 0.0001) components. All clinical scores and the semimembranosus hamstrings component MRI score significantly improved (p < 0.05) over time, though the conjoint component did not (p = 0.219). At 12 months, a higher LEFS was significantly associated with a better semimembranosus MRI score (r = -0.57, p = 0.042), though no other significant correlations (p > 0.05) were observed between clinical and MRI measures.

Conclusions

Excellent reliability was observed for the MRI-based scoring tool, which may prove useful in both a research and clinical setting.

Clinical Outcomes After Open and Endoscopic Repair of Proximal Hamstring Tendon Tears at a Minimum Follow-up of 5 Years

Background

Current evidence supports favorable short-term clinical outcomes with few complications after surgical management of proximal hamstring injuries; however, the durability of clinical benefits beyond approximately 2 years after surgery is unknown.

Purpose

To evaluate patient-reported clinical outcomes and complication rates associated with open and endoscopic repair of proximal hamstring tears at minimum 5-year follow-up.

Study Design

Case series; Level of evidence, 4.

Methods

A single-surgeon registry of patients was queried between October 1, 2014, and December 31, 2017, to identify patients who underwent open or endoscopic repair of a proximal hamstring tear. Patients who reported minimum 5-year follow-up data were included. Multiple patient-reported outcome measures, including the Hip Outcome Score Activities of Daily Living (HOS-ADL) and Sports-Specific (HOS-SS) subscales, 12-Item International Hip Outcome Tool (iHOT-12), and Patient-Reported Outcomes Measurement Information System (PROMIS) Physical Function (PF) and Pain domains, along with surgical complications, were analyzed.

Results

Among 35 eligible patients (65.7% female; mean age, 52.3 ± 8.4 years), 24 had full-thickness tears and 11 had partial-thickness tears. There were 23 open repairs and 12 endoscopic repairs. Mean duration from symptom onset to surgical intervention was 37.9 weeks (range, 1.3-306.9 weeks). At a mean follow-up of 69.0 months (range, 60.0-95.0 months), mean postoperative outcome scores were as follows: HOS-ADL, 86.8 ± 12.7; HOS-SS, 83.1 ± 19.5; iHOT-12, 86.3 ± 14.9; PROMIS-PF, 50.0 ± 11.8; and PROMIS-Pain, 50.2 ± 7.9. Regarding complications, 28.6% of patients had a complication including persistent peri-incisional numbness (11.4%), wound infection (11.4%), postoperative neuropathy (8.6%), and revision surgery (2.9%).

Conclusion

Both open and endoscopic surgical techniques for repair of proximal hamstring injuries produced favorable patient-reported clinical outcomes at a minimum 5-year follow-up.

Systematic Review of Complications Associated With Proximal Hamstring Tendon Repair

Background

Although several complications of proximal hamstring tendon ruptures have been reported in the literature, few studies have comprehensively analyzed the complication profile of proximal hamstring tendon repair.

Purpose

To identify the overall rate of complications following proximal hamstring tendon repair and to differentiate these complications into categories.

Study Design

Systematic review; Level of evidence, 4.

Methods

Included in this review were studies that examined surgical repair of proximal hamstring tendon ruptures; all studies were in English and had an evidence level of 4 or higher. No restrictions were made regarding publication date or methodological quality. Data regarding complications were extracted to calculate the overall complication rate as well as the rate of major and minor complications. A quantitative data synthesis was conducted using the chi-square test to compare the proportion of patients who experienced complications with the endoscopic versus open approach.

Results

A total of 43 articles including 2833 proximal hamstring tendon repairs were identified. The overall postoperative complication rate was 15.3% (n = 433). The rate of major complications was 4.6%, including a 1.7% rate of sciatic nerve injury, 0.8% rate of venous thromboembolism, 0.8% reoperation rate, 0.8% rerupture rate, and 0.4% rate of deep infection. Minor complications included a 2.4% rate of posterior femoral cutaneous nerve injury, 2.3% rate of persistent hamstring myopathy, 2.2% rate of persistent sitting pain, 1.8% rate of peri-incisional numbness, 1.1% rate of superficial infection, and 0.8% rate of hematoma/seroma.

Conclusion

Proximal hamstring tendon repair is associated with an overall complication rate of 15.3%, including a 4.6% rate of major complications.

A systematic review of surgical intervention in the treatment of hamstring tendon ruptures: current evidence on the impact on patient outcomes

Hamstring injuries are among the most common muscle injuries. They have been reported in many different sports, such as running, soccer, track and field, rugby, and waterskiing. However, they are also present among the general population. Most hamstring injuries are mild strains, but also moderate and severe injuries occur. Hamstring injuries usually occur in rapid movements involving eccentric demands of the posterior thigh. Sprinting has been found to mainly affect the isolated proximal biceps femoris, whereas stretching-type injuries most often involve an isolated proximal injury of the semimembranosus muscle. The main cause of severe 2- or 3-tendon avulsion is a rapid forceful hip flexion with the ipsilateral knee extended. Most hamstring injuries are treated non-surgically with good results. However, there are also clear indications for surgical treatment, such as severe 2- or 3-tendon avulsions. In athletes, more aggressive recommendations concerning surgical treatment can be found. For a professional athlete, a proximal isolated tendon avulsion with clear retraction should be treated operatively regardless of the injured tendon. Surgical treatment has been found to have good results in severe injuries, especially if the avulsion injury is repaired in acute phase. In chronic hamstring injuries and recurring ruptures, the anatomical apposition of the retracted muscles is more difficult to be achieved. This review article analyses the outcomes of surgical treatment of hamstring ruptures. The present study confirms the previous knowledge that surgical treatment of hamstring tendon injuries causes good results with high satisfaction rates, both in complete and partial avulsions. Early surgical repair leads to better functional results with lower complication rates, especially in complete avulsions.KEY MESSAGEsSurgical treatment of hamstring tendon ruptures leads to high satisfaction and return to sport rates.Both complete and partial hamstring tendon ruptures have better results after acute surgical repair, when compared to cases treated surgically later.Athletes with hamstring tendon ruptures should be treated more aggressively with operative methods.

Outcomes following surgical management of proximal hamstring tendon avulsions

Aims

Avulsion of the proximal hamstring tendon origin can result in significant functional impairment, with surgical re-attachment of the tendons becoming an increasingly recognized treatment. The aim of this study was to assess the outcomes of surgical management of proximal hamstring tendon avulsions, and to compare the results between acute and chronic repairs, as well as between partial and complete injuries.

Methods

PubMed, CINAHL, SPORTdiscuss, Cochrane Library, EMBASE, and Web of Science were searched. Studies were screened and quality assessed.

Results

In all, 35 studies (1,530 surgically-repaired hamstrings) were included. Mean age at time of repair was 44.7 years (12 to 78). A total of 846 tears were acute, and 684 were chronic, with 520 tears being defined as partial, and 916 as complete. Overall, 92.6% of patients were satisfied with the outcome of their surgery. Mean Lower Extremity Functional Score was 74.7, and was significantly higher in the partial injury group. Mean postoperative hamstring strength was 87.0% of the uninjured limb, and was higher in the partial group. The return to sport (RTS) rate was 84.5%, averaging at a return of 6.5 months. RTS was quicker in the acute group. Re-rupture rate was 1.2% overall, and was lower in the acute group. Sciatic nerve dysfunction rate was 3.5% overall, and lower in the acute group (p < 0.05 in all cases).

Conclusion

Surgical treatment results in high satisfaction rates, with good functional outcomes, restoration of muscle strength, and RTS. Partial injuries could expect a higher functional outcome and muscle strength return. Acute repairs result in a quicker RTS with a reduced rate of re-rupture and sciatic nerve dysfunction. Cite this article: Bone Jt Open 2022;3(5):415–422.

Proximal hamstring tendon avulsions: comparable clinical outcomes of operative and non-operative treatment at 1-year follow-up using a shared decision-making model

OBJECTIVE

To prospectively evaluate 1-year clinical and radiological outcomes after operative and non-operative treatment of proximal hamstring tendon avulsions.

METHODS

Patients with an MRI-confirmed proximal hamstring tendon avulsion were included. Operative or non-operative treatment was selected by a shared decision-making process. The primary outcome was the Perth Hamstring Assessment Tool (PHAT) score. Secondary outcome scores were Proximal Hamstring Injury Questionnaire, EQ-5D-3L, Tegner Activity Scale, return to sports, hamstring flexibility, isometric hamstring strength and MRI findings including proximal continuity.

RESULTS

Twenty-six operative and 33 non-operative patients with a median age of 51 (IQR: 37-57) and 49 (IQR: 45-56) years were included. Median time between injury and initial visit was 12 (IQR 6-19) days for operative and 21 (IQR 12-48) days for non-operative patients (p=0.004). Baseline PHAT scores were significantly lower in the operative group (32±16 vs 45±17, p=0.003). There was no difference in mean PHAT score between groups at 1 year follow-up (80±19 vs 80±17, p=0.97). Mean PHAT score improved by 47 (95% CI 39 to 55, p<0.001) after operative and 34 (95% CI 27 to 41, p<0.001) after non-operative treatment. There were no relevant differences in secondary clinical outcome measures. Proximal continuity on MRI was present in 20 (95%, 1 recurrence) operative and 14 (52%, no recurrences) non-operative patients (p=0.008).

CONCLUSION

In a shared decision-making model of care, both operative and non-operative treatment of proximal hamstring tendon avulsions resulted in comparable clinical outcome at 1-year follow-up. Operative patients had lower pretreatment PHAT scores but improved substantially to reach comparable PHAT scores as non-operative patients. We recommend using this shared decision model of care until evidence-based indications in favour of either treatment option are available from high-level clinical trials.

Evidence-Based Management and Factors Associated With Return to Play After Acute Hamstring Injury in Athletes: A Systematic Review

Background:

Considering the lengthy recovery and high recurrence risk after a hamstring injury, effective rehabilitation and accurate prognosis are fundamental to timely and safe return to play (RTP) for athletes.

Purpose:

To analyze methods of rehabilitation for acute proximal and muscular hamstring injuries and summarize prognostic factors associated with RTP.

Study Design:

Systematic review; Level of evidence, 4.

Methods:

In August 2020, MEDLINE, CINAHL, Cochrane Central Register of Controlled Trials, and SPORTDiscus were queried for studies examining management and factors affecting RTP after acute hamstring injury. Included were randomized controlled trials, cohort studies, case-control studies, and case series appraising treatment effects on RTP, reinjury rate, strength, flexibility, hamstrings-to-quadriceps ratio, or functional assessment, as well as studies associating clinical and magnetic resonance imaging factors with RTP. Risk of bias was assessed using the Cochrane Risk-of-Bias Tool for Randomized Trials or the Methodological Index for Non-Randomized Studies (MINORS).

Results:

Of 1289 identified articles, 75 were included. The comparative and noncomparative studies earned MINORS scores of 18.8 ± 1.3 and 11.4 ± 3.4, respectively, and 12 of the 17 randomized controlled trials exhibited low risk of bias. Collectively, studies of muscular injury included younger patients and a greater proportion of male athletes compared with studies of proximal injury. Surgery for proximal hamstring ruptures achieved superior outcomes to nonoperative treatment, whereas physiotherapy incorporating eccentric training, progressive agility, and trunk stabilization restored function and hastened RTP after muscular injuries. Platelet-rich plasma injection for muscular injury yielded inconsistent results. The following initial clinical findings were associated with delayed RTP: greater passive knee extension of the uninjured leg, greater knee extension peak torque angle, biceps femoris injury, greater pain at injury and initial examination, “popping” sound, bruising, and pain on resisted knee flexion. Imaging factors associated with delayed RTP included magnetic resonance imaging-positive injury, longer lesion relative to patient height, greater muscle/tendon involvement, complete central tendon or myotendinous junction rupture, and greater number of muscles injured.

Conclusion:

Surgery enabled earlier RTP and improved strength and flexibility for proximal hamstring injuries, while muscular injuries were effectively managed nonoperatively. Rehabilitation and athlete expectations may be managed by considering several suitable prognostic factors derived from initial clinical and imaging examination.

[Clinical results after refixation of proximal hamstring tendon ruptures comparing different anchor systems]

BACKGROUND

Injuries to the hamstring muscles and tendon complex are among the most frequent muscular injuries with proximal hamstring tendon avulsion being a particularly severe form. The surgical treatment of these injuries is superior to conservative management with respect to patient satisfaction, recovery of muscle strength and function as well as return to sport rates. It is therefore the method of choice.

OBJECTIVE

Presentation and comparison of the surgical results after treatment with titanium, polyether ether ketone (PEEK) and all suture anchors.

MATERIAL AND METHODS

A systematic search was carried out in the PubMed medical database and the results are summarized.

RESULTS

All systems exhibit comparable biomechanical properties regarding elongation and ultimate failure load. Tendon repair with these anchors results in good to excellent clinical outcomes and shows high return to sport and low complication rates. Patient satisfaction after hamstring tendon repair is reported to be over 90% and return to sport rate is 80-100%. The muscle strength recovers to 80-90% in comparison to the contralateral side.

CONCLUSION

All available anchors systems provide good to excellent clinical outcomes and an explicit advantage for one anchor system could so far not be shown.

Systematic Review of Outcome Measures Used After Proximal Hamstring Repair

Background:

Patient-reported outcome measures are important to determine outcomes after orthopaedic procedures. There is currently no standard for outcome measures in the evaluation of patient outcomes after proximal hamstring repair.

Purpose:

To identify and evaluate outcome measures used after proximal hamstring repair.

Study Design:

Systematic review; Level of evidence, 4.

Methods:

A systematic review was performed to identify all English-language articles assessing outcomes after proximal hamstring repair in PubMed, Embase, CINAHL via EBSCOhost, MEDLINE via OvidSP, and Web of Science between 2000 and 2019. After duplicates were removed, studies were selected using eligibility criteria established by the authors. Image reviews, anatomic/histology studies, literature reviews, surgical technique reports, systematic reviews, narrative reviews, case studies, and studies with <5 patients were excluded. Extraction, synthesis, and analysis of outcome measure data were performed using Microsoft Excel. Quality assessment of included studies was performed using Methodological Index for Non-Randomized Studies criteria.

Results:

After duplicate articles were removed, a total of 304 unique articles were identified and 27 met the inclusion criteria. The mean number of patients with proximal hamstring repairs per study was 40. The most frequently reported outcome measures were return to sport (14/27; 51.9%), custom survey/questionnaire (13/27; 48.1%), and isokinetic hamstring strength testing (13/27; 48.1%). Six of the 10 most commonly used outcome measures were validated and included Lower Extremity Functional Scale, 12-Item Short Form Health Survey, visual analog scale for pain, Perth Hamstring Assessment Tool (PHAT), Single Assessment Numeric Evaluation, and Tegner Activity Scale. Of those, PHAT was the only validated outcome measure designed for proximal hamstring repair.

Conclusion:

There is currently no consensus on the best outcome measurements for the evaluation of patients after proximal hamstring repair. We recommend an increased commitment to the use of return to sport, isokinetic strength testing, Lower Extremity Functional Scale, and PHAT when assessing such injuries. Future studies should aim to define the most reliable methods of outcome measurement in this patient population through consistent use of tools that are clinically relevant and important to patients and can easily be employed in a variety of clinical scenarios.

Outcomes of Open and Endoscopic Repairs of Chronic Partial- and Full-Thickness Proximal Hamstring Tendon Tears: A Multicenter Study With Minimum 2-Year Follow-up

BACKGROUND

The preponderance of literature on the repair of proximal hamstring tendon tears focuses on the acute phase (<4 weeks). As such, there is a paucity of data reporting on the outcomes of chronic proximal hamstring tears.

PURPOSE

To report minimum 2-year postoperative patient-reported outcome (PRO) scores, visual analog scale (VAS) for pain, and patient satisfaction from patients who underwent open or endoscopic repair of partial- and full-thickness chronic proximal hamstring tendon tears.

STUDY DESIGN

Case series study; Level of evidence, 4.

METHODS

Between April 2002 and May 2017, prospectively collected data from 3 tertiary care institutions were retrospectively reviewed for patients who underwent open and endoscopic repair of partial- and full-thickness chronic proximal hamstring tendon tears. Patients were included only if they had a chronic proximal hamstring tear (defined as ≥4 weeks from symptom onset to surgery). Patients were excluded if they had a tear treated <4 weeks after injury, underwent hamstring reconstruction, or claimed workers' compensation. Patients who reported minimum 2-year follow-up for VAS, patient satisfaction, and the following PROs had their outcomes analyzed: the modified Hip Harris Score, Non-arthritic Hip Score, iHOT-12 (International Hip Outcome Tool), and Hip Outcome Score-Sports Specific Subscale.

RESULTS

Fifty patients (34 females and 16 males) were included in this study. There were 19 endoscopic repairs and 31 open repairs. Within the cohort, 52.0% had a full-thickness tendon tear on magnetic resonance imaging, and 48.0% had a partial tear. Average follow-up time was 58.07 ± 37.27 months (mean ± SD; range, 24-220 months). The mean age and body mass index of the group were 46.13 ± 13 years and 25.43 ± 5.14. The average time from injury to surgery was 66.73 weeks (range, 5.14-215.14 weeks). Average postoperative PROs were as follows: modified Hip Harris Score, 91.94 ± 9.96; Non-arthritic Hip Score, 91.33 ± 9.99; iHOT-12, 87.17 ± 17.54; Hip Outcome Score-Sports Specific Subscale, 87.15 ± 18.10; and VAS, 1.16 ± 1.92. Patient satisfaction was 8.22 ± 1.20.

CONCLUSION

Patients who underwent open and endoscopic repairs for chronic partial- and full-thickness proximal hamstring tendon tears reported high PROs and satisfaction at a minimum 2-year follow-up with low rates of complications.

Chemoprotection with botulinum toxin following proximal hamstring-Ischial tuberosity avulsion fracture repair: Running title: Chemoprotection for hamstring avulsion fractures

INTRODUCTION

Surgical treatment for avulsion injuries of the proximal hamstrings has gained increasing popularity over the past decade. Despite good outcomes, early failures have been noted and have been attributed to slipping and falling, postoperative muscle spasm, or early mobilization. In a recent review of hamstring repair rehabilitation protocols, it was shown that there is marked variability in post-operative management. Post-operative bracing with limiting knee extension and hip flexion is the standard of care in most early rehabilitation protocols. Braces with limitation of hip flexion and knee locked in 90⁰ flexion can be awkward, cumbersome and create fall risk.Chemoprotection has more recently been proposed to be an alternative approach to prevent tendon repair failure and controlled mobilization which has been shown to be superior to complete immobilization. We present the first case series of the use of botulinum toxin for chemo-protection of the proximal hamstring ischial avulsion repair, demonstrating its safety and efficacy.

METHODS

Retrospective case series at a tertiary children's hospital which included patients <18 years of age who underwent interventional treatment for proximal hamstring avulsion injuries of the ischium utilizing botulinum toxin as a chemoprotective agent. Data collected included demographic data, injury and treatment details, imaging, post-operative rehabilitation and return to activity. Descriptive statistical analysis was conducted.

RESULTS

Five male patients with mean age 14 years (12-17) were included in the study. All were sports related non-contact injuries. Radiographs showed displaced avulsion fractures in all 5 patients. All patients had failed conservative management initially; mean time to surgery from initial injury was 34.4 weeks. 4 patients underwent open reduction and internal fixation (ORIF), 1 patient with less displacement had bone marrow aspirate (BMA) injection; all had chemoprotection using botulinum toxin injected in the hamstrings. No patient required hip immobilization or knee immobilization locked to 90°. We elected to use a brace locked at 20° knee flexion in 2/5 patients. All patients underwent supervised physical therapy and achieved symmetric knee range of motion (ROM). Post-operative radiographs confirmed healing of the avulsion fracture in all 5 patients and they all returned to previous level of activity at mean 32 weeks (21-43) from surgery. None of the patients had a hamstring re-injury at mean follow up of 27 months (11-42).

CONCLUSION

Our case series is the first in literature that shows the safety and efficacy of chemoprotection with botulinum toxin for the post-operative management of avulsion injuries of proximal hamstrings, by minimizing the need for cumbersome bracing and allowing controlled motion during physical therapy.

Return to Sport After Surgical Management of Proximal Hamstring Avulsions: A Systematic Review and Meta-analysis

OBJECTIVE

To assess the rates and timing of return to sport for the surgical management of proximal hamstring avulsions (PHAs).

METHODS

Three databases, PubMed, MEDLINE, and EMBASE, were searched from database inception until October 7, 2017, by 2 reviewers independently and in duplicate. The inclusion criteria were studies reporting return to sport outcomes for surgical management of acute, chronic, complete, and partial PHA. The rate of return to sports was combined in a meta-analysis of proportions using a random-effects model.

RESULTS

Overall, 21 studies with a total of 846 patients met the inclusion criteria, with a mean age of 41.4 years (range, 14-71 years) and a mean follow-up of 37.8 months (range, 6-76 months). Two studies were of prospective comparative design (level II), 2 were retrospective comparative (level III), 8 were prospective case series (level IV), and 9 were retrospective case series (level IV). The overall mean time to return to sport was 5.8 months (range, 1-36 months). The pooled rate of return to any sport participation was 87% [95% confidence interval (CI), 77%-95%]. The pooled rate of return to preinjury level of sport was 77% (95% CI, 66%-86%).

CONCLUSIONS

Pooled results suggest a high rate of return to sport after surgical management of PHA; however, this was associated with a lower preinjury level of sport. No major differences in return to sport were found between partial versus complete and acute versus chronic PHA.

Strength assessment after proximal hamstring rupture: A critical review and analysis

BACKGROUND

Muscular strength should be one of the main parameters to assess the interest or not of surgery after proximal hamstring rupture. Yet, this parameter is difficult to compare between the different studies because of the heterogeneous assessment methods.

METHODS

We realized a critical review of strength assessment methods used to evaluate treatments performed after proximal hamstring rupture. The studies were selected from several medical databases with the keywords: "proximal hamstring rupture" OR "proximal hamstring avulsion" AND "strength" OR "isokinetic".

FINDINGS

24 articles evaluated muscular strength after proximal hamstring rupture. 7 have been excluded because the method was not described. 6 types of dynamometric evaluation were used: 2 with an isometric method, 3 with a pneumatic isotonic method and 13 with an isokinetic method. Muscular strengths after non-surgical treatment could not be compared because of the low number of studies and different methods of assessment. After surgery, only isokinetic results measured at the angular speed of 60°/s could have been weighted. A 15% strength deficit was shown at >12 months after surgery.

INTERPRETATION

Muscular strength assessment methods currently used to evaluate the strength after proximal hamstring rupture are too disparate to clearly define the strength deficit after rupture and surgery. Strength evaluation should be more rigorous in order to prove the real interest of the surgical management.

Proximal hamstring tendon avulsion treatment choice depends on a combination of clinical and imaging-related factors: a worldwide survey on current clinical practice and decision-making

Objectives

To evaluate current practice in the treatment of proximal hamstring tendon avulsions and identify decision-making preferences.

Methods

An invitation to an anonymous e-survey containing 32 questions was sent to 3475 members of the International Society of Arthroscopy, Knee Surgery and Orthopaedic Sports Medicine (ISAKOS) and the European College of Sports and Exercise Physicians (ECOSEP).

Results

We received 403 (12%) unique responses with a completion rate of 79%. Participants were orthopaedic/trauma surgeons (90%), sports medicine physicians (7%) or physical therapists (2%). For 83% of the participants, the preferred treatment (ie, surgical or non-operative) depends on the individual case. Participants base their decision-making process on patient- and injury-related factors (decision modifiers). The five most frequently selected decision modifiers that support the choice for surgical treatment were diminished function (84%), neurological symptoms (74%), involved tendons (82%), tendon retraction on MRI (84%) and patient preference for surgery (78%). The majority prefer early surgical repair (<2 weeks after injury) to achieve highest functional outcome (63%) and ensure a low complication risk (61%). Suture anchors are used by 93% of the participants for tendon reattachment. Estimated recovery duration (ie, time to return to sports) was a median 12 weeks (IQR: 12–20) for non-operative treatment and 17 weeks (IQR: 12–24) for surgical treatment. Estimated reinjury risk was a median 25% (IQR: 10–31.5) and 10% (IQR: 5–20), respectively.

Conclusion

This survey among experienced medical professionals has summarised current practice and identified treatment decision-making preferences. The typical surgical patient has a retracted (>2 cm) two-tendon avulsion (ie, common tendon and semimembranosus tendon), is unable to engage in sports or activities of daily life, reports sciatic symptoms and prefers surgical treatment. Surgery is thought to prolong recovery and decrease reinjury risk compared with non-operative treatment and is preferably performed early.

Level of evidence

Level V.

Return to Sport After Proximal Hamstring Tendon Repair: A Systematic Review

Background:

Previous studies have evaluated functional outcomes and return-to-sport rates after proximal hamstring tendon (HT) repair.

Purpose:

To systematically review the literature in an effort to evaluate return-to-sport rates after proximal HT repair.

Study Design:

Systematic review; Level of evidence, 4.

Methods:

A systematic review was performed by searching PubMed, the Cochrane Library, and Embase to identify studies that evaluated postoperative lower extremity function and return-to-sport rates in patients after proximal HT repair. Search terms used were “hamstring,” “repair,” “return to sport,” and “return to play.” Patients were assessed based on return to sport, return to preinjury activity level, type of HT tear (complete or partial), and interval from injury to surgery. Patients were also divided into subgroups depending on timing of the surgical intervention: early, <1 month; delayed, 1 to 6 months; and late, >6 months from the time of injury.

Results:

Sixteen studies (one level 2, five level 3, ten level 4) met the inclusion criteria, including 374 patients with a complete proximal HT tear (CT group) and 93 patients with a partial proximal HT tear (PT group), with a mean follow-up of 2.9 years. Overall, 93.8% of patients (438/467) returned to sport, including 93.0% (348/374) in the CT group and 96.8% (90/93) in the PT group (P = .18). The mean time to return to sport was 5.7 months, and 83.5% of patients (330/395) returned to their preinjury activity level. The early group demonstrated the greatest rate of return to sport at 94.4% (186/197) as well as the quickest time to return at a mean of 4.8 months, although this was not found to be statistically significant.

Conclusion:

Over 90% of patients undergoing repair of a complete or partial proximal HT tear can be expected to return to sport regardless of the tear type. Early surgical interventions of these injuries may be associated with a quicker return to sport, although the rate of return to sport does not differ based on timing of the surgical intervention.

Variability of United States Online Rehabilitation Protocols for Proximal Hamstring Tendon Repair

Background

The optimal postoperative rehabilitation protocol following repair of complete proximal hamstring tendon ruptures is the subject of ongoing investigation, with a need for more standardized regimens and evidence-based modalities.

Purpose

To assess the variability across proximal hamstring tendon repair rehabilitation protocols published online by United States (US) orthopaedic teaching programs.

Study Design

Cross-sectional study.

Methods

Online proximal hamstring physical therapy protocols from US academic orthopaedic programs were reviewed. A web-based search using the search term complete proximal hamstring repair rehabilitation protocol provided an additional 14 protocols. A comprehensive scoring rubric was developed after review of all protocols and was used to assess each protocol for both the presence of various rehabilitation components and the point at which those components were introduced.

Results

Of 50 rehabilitation protocols identified, 35 satisfied inclusion criteria and were analyzed. Twenty-five protocols (71%) recommended immediate postoperative bracing: 12 (34%) prescribed knee bracing, 8 (23%) prescribed hip bracing, and 5 (14%) did not specify the type of brace recommended. Fourteen protocols (40%) advised immediate nonweightbearing with crutches, while 16 protocols (46%) permitted immediate toe-touch weightbearing. Advancement to full weightbearing was allowed at a mean of 7.1 weeks (range, 4-12 weeks). Most protocols (80%) recommended gentle knee and hip passive range of motion and active range of motion, starting at a mean 1.4 weeks (range, 0-3 weeks) and 4.0 weeks (range, 0-6 weeks), respectively. However, only 6 protocols (17%) provided specific time points to initiate full hip and knee range of motion: a mean 8.0 weeks (range, 4-12 weeks) and 7.8 weeks (range, 0-12 weeks), respectively. Considerable variability was noted in the inclusion and timing of strengthening, stretching, proprioception, and cardiovascular exercises. Fifteen protocols (43%) required completion of specific return-to-sport criteria before resuming training.

Conclusion

Marked variability is found in both the composition and timing of rehabilitation components across the various complete proximal hamstring repair rehabilitation protocols published online. This finding mirrors the variability of proposed rehabilitation protocols in the professional literature and represents an opportunity to improve patient care.

A Comparison of Nonoperative and Operative Treatment of Complete Proximal Hamstring Ruptures

Background:

The early repair of acute proximal hamstring ruptures provides better clinical results than delayed repair. However, it is unclear how nonoperative treatment compares with the operative treatment of these injuries.

Purpose:

To compare the clinical results of the nonoperative and operative treatment of acute proximal hamstring ruptures.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

A total of 25 patients with complete, retracted proximal hamstring ruptures presenting to 1 institution were retrospectively reviewed. All patients were given the option of proximal hamstring repair at the time of the initial evaluation. Patients with at least 12 months of follow-up from the time of surgery or injury were included in the evaluation. Both nonoperative and operative treatment groups were evaluated using the same outcome measures. The primary outcome measure was the Lower Extremity Functional Scale (LEFS). Secondary outcome measures included the Short Form–12 (SF-12) physical and mental component summaries, strength testing, a single-leg hop test, the patient’s perception of strength, and the ability to return to activity.

Results:

There were 11 patients treated nonoperatively, with a mean follow-up of 2.48 ± 3.66 years, and 14 patients treated operatively, with a mean follow-up of 3.56 ± 2.11 years. The mean LEFS scores for the nonoperative and operative groups were 68.50 ± 7.92 and 74.71 ± 5.38, respectively (P = .07). No statistical differences were found between the groups regarding SF-12 scores and mean single-leg hop distance compared with the uninjured leg. Isometric testing of the injured hamstring in the nonoperative group demonstrated significant clinical weakness compared with the uninjured side at both 45° and 90° of flexion (57.54% ± 7.8% and 67.73% ± 18.8%, respectively). Isokinetic testing of the injured leg in the operative group demonstrated 90.87% ± 16.3% strength of the uninjured leg. All patients in the operative group were able to return to preinjury activities, whereas 3 patients in the nonoperative group were unable to return (chi-square = 4.33, P = .07).

Conclusion:

Patients with acute proximal hamstring ruptures treated surgically regained approximately 90% strength of the uninjured extremity and tended to have a greater likelihood of returning to preinjury activities than patients treated nonoperatively.

Nerve Wrapping of the Sciatic Nerve With Acellular Dermal Matrix in Chronic Complete Proximal Hamstring Ruptures and Ischial Apophyseal Avulsion Fractures

BACKGROUND

Patients with chronic injuries of the proximal hamstring can develop significant impairment because of weakness of the hamstring muscles, sciatic nerve compression from scar formation, or myositis ossificans.

PURPOSE

To describe the surgical outcomes of patients with chronic injury of the proximal hamstrings who were treated with hamstring repair and sciatic neurolysis supplemented with nerve wrapping with acellular dermal matrix.

STUDY DESIGN

Retrospective case series; Level of evidence, 4.

METHODS

Fifteen consecutive patients with a diagnosis of chronic complete proximal hamstring rupture or chronic ischial tuberosity apophyseal avulsion fracture (mean age, 39.67 years; range, 14-69 years) were treated with proximal hamstring repair and sciatic neurolysis supplemented with nerve wrapping with acellular dermal matrix. Nine patients had preoperative sciatica, and 6 did not. Retrospective chart review recorded clinical outcomes measured by the degree of pain relief, the rate of return to activities, and associated postoperative complications.

RESULTS

All 15 patients were followed in the postoperative period for an average of 16.6 months. Postoperatively, there were 4 cases of transient sciatic nerve neurapraxia. Four patients (26%) required postoperative betamethasone sodium phosphate (Celestone Soluspan) injectable suspension USP 6 mg/mL. Among the 9 patients with preoperative sciatica, 6 (66%) had a good or excellent outcome and were able to return to their respective activities/sports; 3 (33%) had persistent chronic pain. One of these had persistent sciatic neuropathy that required 2 surgical reexplorations and scar excision after development of recurrent extraneural scar formation. Among the 6 without preoperative sciatica, 100% had a good or excellent outcomes and 83% returned to their respective activities/sports. Better outcomes were observed in younger patients, as the 3 cases of persistent chronic sciatic pain were in patients older than 45 years.

CONCLUSION

This study suggests that when used as an adjunct to sciatic neurolysis, nerve wrapping with acellular dermal matrix can be a safe and effective method of treating younger patients with and preventing the development of sciatic neuropathic pain after chronic injury of the proximal hamstrings.

The adductor magnus "mini-hamstring": MRI appearance and potential pitfalls

OBJECTIVE

To examine the anatomic MRI characteristics of the adductor magnus mini hamstring (AMMH) and explore its involvement in cases of hamstring avulsion.

MATERIALS AND METHODS

An IRB-approved retrospective review of patients undergoing "hamstring protocol" MRI between March 2009 and June 2014 was performed. Two musculoskeletal radiologists recorded multiple AMMH anatomic characteristics and involvement in cases of hamstring avulsion.

RESULTS

Seventy-six AMMHs were analyzed in 66 patients [35 females and 31 males, mean age 49.3 ± 15.2 years (range 17-81)]. Eleven percent of AMMHs were poorly visualized, 51 % visualized, and 37 % well visualized. Seven percent demonstrated round, 73 % ovoid, and 21 % flat/lenticular tendon morphologies. Most (88 %) demonstrated typical origins. Average cross-sectional area (CSA) was 22.4 ± 10.6 mm² (range 6-56), diameter was 7.2 ± 2.5 mm (range 2.9-15), medial distance from the semimembranosus tendon was 7.5 ± 2.5 mm (range 3-14), and tendon length was 6.8 ± 3.3 cm (range 1.2-14.1). There was no gender difference in AMMH anatomic measurements or correlation between age and CSA or diameter. Of 17 complete hamstring avulsion cases, the AMMH was intact in 13, partially torn in 3, and completely torn in 1.

CONCLUSION

The AMMH is a constant finding with variable anatomic characteristics. It is visualized or well visualized by MRI in 88 % of cases and is a sizable tendon located in close proximity to the semimembranosus tendon. Because it is uncommonly completely torn (6 %) in cases of complete hamstring avulsion, radiologists should be aware of its presence and appearance to avoid diagnostic confusion.

Outcome After Surgical Repair of Proximal Hamstring Avulsions: A Systematic Review

BACKGROUND

At the present time, no systematic review, including a quality assessment, has been published about the outcome after proximal hamstring avulsion repair.

PURPOSE

To determine the outcome after surgical repair of proximal hamstring avulsions, to compare the outcome after acute (≤4 weeks) and delayed repairs (>4 weeks), and to compare the outcome after different surgical techniques.

STUDY DESIGN

Systematic review and best-evidence synthesis.

METHODS

PubMed, CINAHL, SPORTdiscus, Cochrane library, EMBASE, and Web of Science were searched (up to December 2013) for eligible studies. Two authors screened the search results separately, while quality assessment was performed by 2 authors independently using the Physiotherapy Evidence Database (PEDro) scale. A best-evidence synthesis was subsequently used.

RESULTS

Thirteen studies (387 participants) were included in this review. There were no studies with control groups of nonoperatively treated proximal hamstring avulsions. All studies had a low methodological quality. After surgical repair of proximal hamstring avulsion, 76% to 100% returned to sports, 55% to 100% returned to preinjury activity level, and 88% to 100% were satisfied with surgery. Mean hamstring strength varied between reporting studies (78%-101%), and hamstring endurance and flexibility were fully restored compared with the unaffected side. Symptoms of residual pain were reported by 8% to 61%, and reported risk of major complications was low (3% rerupture rate). No to minimal difference in outcome was found between acute and delayed repair in terms of return to sports, patient satisfaction, hamstring strength, and pain. Achilles allograft reconstruction and primary repair with suture anchors led to comparable results.

CONCLUSION

The quality of studies included is low. Surgical repair of proximal hamstring avulsions appears to result in a subjective highly satisfying outcome. However, decreased strength, residual pain, and decreased activity level were reported by a relevant number of patients. Minimal to no differences in outcome of acute and delayed repairs were found. Limited evidence suggests that an Achilles allograft reconstruction yields results comparable with primary repair in delayed cases where primary repair is not possible. High-level studies are required to confirm these findings.

Surgical Management of Recurrent Musculotendinous Hamstring Injury in Professional Athletes

BACKGROUND

Hamstring injury is the most common muscular lesion in athletes. The conservative treatment is well described, and surgical management is often indicated for proximal tendinous avulsions. To our knowledge, no surgical treatment has been proposed for failure of conservative treatment in musculotendinous hamstring lesions.

PURPOSE

To describe the surgical management of proximal and distal hamstring musculotendinous junction lesions in professional athletes after failure of conservative treatment.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

A consecutive series of 10 professional athletes, including 4 soccer players, 4 rugby players, and 2 handball players, underwent surgical intervention between October 2010 and June 2014 for the treatment of recurrent musculotendinous hamstring injuries. All athletes had failed at least 3 months of conservative treatment for a recurrent musculotendinous hamstring injury. Surgical resection of the musculotendinous scar tissue was performed using a longitudinal muscular suture. Lower Extremity Functional Scale (LEFS) and Marx scores were obtained at the 3-month follow-up, and a final phone interview was completed to determine recurrence of hamstring injury and return to previous level of play.

RESULTS

The mean age at surgery was 25.2 years (range, 19-35 years). The musculotendinous hamstring lesions involved 8 semitendinosus and 2 biceps femoris, with 6 injuries located proximally and 4 distally. Conservative treatment lasted a mean 5.1 months (range, 3-9 months) after last recurrence, and the patients had an average of 2.7 (range, 2-5) separate incidents of injury recurrence before surgical intervention was decided upon. At the 3-month follow-up, all patients had Marx activity scores of 16 and LEFS scores of 80. All 10 patients returned to the same level of play at a mean 3.4 months (range, 2-5 months). At a mean follow-up of 28.7 months, none of the athletes had suffered a recurrence. No surgical complication was encountered.

CONCLUSION

In cases of failed conservative treatment of musculotendinous hamstring lesions, surgical intervention may be a viable treatment option in professional athletes and allows the patient to return to the same level of play.

Gross anatomical and dimensional characteristics of the proximal hamstring origin

PURPOSE

The current study was undertaken to better define the gross anatomical and dimensional characteristics of the proximal hamstring origin.

METHODS

Twelve paired whole-lower extremities from six embalmed cadavers were dissected. The gross anatomy of the proximal hamstrings was studied. With the tendons attached to the ischial tuberosity, the width and thickness of each tendon was measured 1 cm distally to their origin, and the distance from the most proximal border of the common origin of the semitendinosus (ST) and long head of the biceps (LB) to their distal junction was assessed. After removal of the hamstring group, the shape, orientation, and dimension of the tendon footprints were determined.

RESULTS

One cadaver demonstrated unique anatomy, which was considered as an anatomic variant and was therefore excluded from the study group. The ST and LB had a common origin on the posterolateral aspect of the ischial tuberosity (ST/LB), whereas the semimembranosus (SM) had a separated origin at the anterolateral aspect. The mean distance from the most proximal border of the ST/LB origin to the distal junction was 10.0 ± 1.3 cm. The shape of both footprints was longitudinal-oval, with the longitudinal axes of the SM and ST/LB footprints parallel aligned. Mean tendon width was 3.4 ± 0.5 cm for the common ST/LB complex and 4.2 ± 0.9 cm for the SM (p = 0.009). The corresponding values for tendon thickness were 1.0 ± 0.3 cm (ST/LB) and 0.8 ± 0.2 cm (SM), respectively (n.s.). Mean footprint length was 3.9 ± 0.4 cm for ST/LB and 4.5 ± 0.5 cm for SM (p = 0.002). The corresponding values for footprint height were 1.4 ± 0.5 cm (ST/LB) and 1.2 ± 0.3 cm (SM), respectively (n.s.).

CONCLUSION

The ST and LB had a common origin, whereas the SM originated separately. The site of origin of both tendons was the lateral aspect of the ischial tuberosity, with the SM footprint lying directly anterior to the footprint of the ST/LB complex. The footprint of the SM was significantly wider than the footprint of the ST/LB. The reported gross anatomic findings and dimensions may aid surgeons in anchor placement at the anatomical attachment site, thereby facilitating anatomic hamstring repair. In addition, the provided data may improve diagnosis and conservative treatment of proximal hamstring tendinopathy, since detailed knowledge about the normal anatomy is crucial for recognizing tendon abnormalities and for several conservative treatment modalities such as shockwave application or ultrasound-guided injections.

Proximal Hamstring Repair Strength: A Biomechanical Analysis at 3 Hip Flexion Angles

Background:

Proximal hamstring repair for complete ruptures has become a common treatment. There is no consensus in the literature about postoperative rehabilitation protocols following proximal hamstring repair. Some protocols describe bracing to prevent hip flexion or knee extension while others describe no immobilization. There are currently no biomechanical studies evaluating proximal hamstring repairs; nor are there any studies evaluating the effect of different hip flexion angles on these repairs.

Hypothesis:

As hip flexion increases from 0° to 90°, there will be a greater gap with cyclical loading.

Study Design:

Controlled laboratory study.

Methods:

Proximal hamstring insertions were detached from the ischial tuberosity in 24 cadavers and were repaired with 3 single-loaded suture anchors in the hamstring footprint with a Krakow suture technique. Cyclic loading from 10 to 125 N at 1 Hz was then performed for 0°, 45°, and 90° of hip flexion for 1500 cycles. Gap formation, stiffness, yield load, ultimate load, and energy to ultimate load were compared between groups using paired t tests.

Results:

Cyclic loading demonstrated the least amount of gap formation (P < .05) at 0° of hip flexion (2.39 mm) and most at 90° of hip flexion (4.19 mm). There was no significant difference in ultimate load between hip flexion angles (326, 309, and 338 N at 0°, 45°, and 90°, respectively). The most common mode of failure occurred with knot/suture failure (n = 17).

Conclusion:

Increasing hip flexion from 0° to 90° increases the displacement across proximal hamstring repairs. Postoperative bracing that limits hip flexion should be considered.

Clinical Relevance:

Repetitive motion involving hip flexion after a proximal hamstring repair may cause compromise of the repair.

Structural properties of the intact proximal hamstring origin and evaluation of varying avulsion repair techniques: an in vitro biomechanical analysis

BACKGROUND

Although surgical repair has been reported to provide improved outcomes compared with nonoperative treatment in the management of complete proximal hamstring origin avulsions, no intact or avulsion repair biomechanical data exist to support various repair strategies or guide postoperative rehabilitation.

PURPOSE

To compare failure load among 4 proximal hamstring tendon conditions: (1) intact, (2) repair with 2 small anchors (2S), (3) repair with 2 large anchors (2L), and (4) repair with 5 small anchors (5S).

STUDY DESIGN

Controlled laboratory study.

METHODS

Twenty-four human cadaveric hemipelvises were randomly allocated to 1 of the 4 testing groups. Intact and repaired specimens were subjected to cyclic loading at 1 Hz between 25 N and a progressively increasing maximum load that was incremented by 200 N every 50 cycles, beginning at 200 N and increasing to 1600 N. Displacement, maximum load, stiffness, number of cycles to failure, and mode of failure during cyclic loading were recorded and analyzed.

RESULTS

The intact proximal hamstring tendons failed at the highest cyclic force of all tested groups, yet no significant differences existed between the intact (1405 ± 157 N) and 5S repair (1164 ± 294 N) conditions. Both the 2S and the 2L repair groups failed at a level significantly lower than the intact hamstring (474 ± 145 N [P < .001] and 543 ± 245 N [P < .001], respectively). The maximum load attained by the 5S repairs was significantly greater than the loads attained by the 2S (P = .005) and 2L (P = .013) repairs.

CONCLUSION

Repairs using 5 small anchors were similar to the intact tendon and were significantly stronger than repairs using only 2 large or 2 small anchors in the repair of complete avulsions of the proximal hamstring tendons. Additionally, no significant differences in strength were observed when only anchor size differed.

CLINICAL RELEVANCE

This finding supports the clinical investigation of postoperative range of motion rehabilitation protocols that permit full flexion and extension of the hip and knee when a 5-anchor repair construct is used.

Functional Outcomes and Return to Sports After Acute Repair, Chronic Repair, and Allograft Reconstruction for Proximal Hamstring Ruptures

BACKGROUND

There are limited data regarding outcomes and return to sports after surgery for acute versus chronic proximal hamstring ruptures.

HYPOTHESIS

Surgery for chronic proximal hamstring ruptures leads to improved outcomes and return to sports but at a lower level than with acute repair. Proximal hamstring reconstruction with an Achilles allograft for chronic ruptures is successful when direct repair is not possible.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Between 2002 and 2012, a total of 72 patients with a traumatic proximal hamstring rupture (51 acute, 21 chronic) underwent either direct tendon repair with suture anchors (n = 58) or Achilles allograft tendon reconstruction (n = 14). Results from the Single Assessment Numeric Evaluation (SANE) for activities of daily living (ADL) and sports-related activities, Short Form-12 (SF-12), visual analog scale (VAS), and a patient satisfaction questionnaire were obtained.

RESULTS

The mean time to surgery in the chronic group was 441.4 days versus 17.8 days in the acute group. At a mean follow-up of 45 months, patients with chronic tears had inferior sports activity scores (70.2% vs 80.3%, respectively; P = .026) and a trend for decreased ADL scores (86.5% vs 93.3%, respectively; P = .085) compared with those with acute tears. Patients with chronic tears, however, reported significant improvements postoperatively for both sports activity scores (30.3% to 70.2%; P < .01) and ADL scores (56.1% to 86.5%; P < .01). Greater than 5 to 6 cm of retraction in the chronic group was predictive of the need for allograft reconstruction (P = .015) and resulted in ADL and sports activity scores equal to those of chronic repair (P = .507 and P = .904, respectively). There were no significant differences between groups in SF-12, VAS, or patient satisfaction outcomes (mean, 85.2% satisfaction overall).

CONCLUSION

Acute repair was superior to chronic surgery with regard to return to sports. Acute and chronic proximal hamstring repair and allograft reconstruction had favorable results for ADL. For low-demand patients or those with medical comorbidities, delayed repair or reconstruction might be considered with an expected 87% return to normal ADL. For patients who desire to return to sports, acute repair is recommended.

Self-reported and performance-based functional outcomes after surgical repair of proximal hamstring avulsions

BACKGROUND

Because a proximal hamstring avulsion results in residual loss of function, surgical repair is recommended. Few studies have investigated postoperative function with validated outcomes.

PURPOSE

To examine lower extremity function after surgical repair of proximal hamstring avulsions using validated self-reported and performance-based functional outcomes.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Operative records from 2006 to 2010 were retrospectively reviewed in 3 hospitals. A total of 39 patients who had undergone surgical repair of a proximal hamstring avulsion were identified, and 36 met the inclusion criteria. Thirty-one patients completed questionnaires with demographic background data and quality of life-related questions: the Lower Extremity Functional Scale (LEFS) and the Proximal Hamstring Injury Questionnaire (PHIQ). Thirty patients were evaluated using a Biodex dynamometer for isokinetic quadriceps and hamstring strength measurements at a velocity of 60 deg/s, and 27 patients performed 4 single-legged hop tests.

RESULTS

Twenty-eight repairs were acute (<4 weeks), and 3 were chronic. There were complete ruptures of all 3 tendons in 17 (55%) cases. The mean follow-up was 30 months. Most patients experienced little or no pain or limitations during activities of daily living. The mean LEFS score was 89%, and 29 (94%) of the 31 patients were satisfied with the result after surgery. Eighteen (58%) of the 31 patients had returned to their preinjury activity level. Significant differences in the mean hamstring strength (peak torque) (P < .001) and single-legged hop test (P = .01) between the uninvolved and involved leg were found. Twenty-two (71%) of the 31 patients did not fully trust their operated leg during physical activities and feared sustaining a hamstring injury. Return to activity significantly correlated with the single-legged hop test, the LEFS score, and the questions regarding trust and fear.

CONCLUSION

In this study, using both validated self-reported and performance-based outcome measures after surgical repair of proximal hamstring avulsions, minor pain and limitations to activities of daily living were seen. Isokinetic hamstring strength in the operated leg was significantly lower compared with the nonoperated leg, and a majority of the patients did not trust the operated leg completely during physical activity.