Avulsion of the proximal hamstring origin

Conservative management of proximal hamstring avulsion: A clinical study

Introduction

The management of proximal hamstring tear (PHT) is debated and consensus regarding recommended measures and individual treatment regimens is lacking. The present investigation evaluated the efficacy of a conservative management of partial and complete PHT.

Methods

The present observational study was conducted following the STROBE statement. In June 2018 the medical databases of the BG Klinikum Bergmannstrost Halle, Germany were accessed. All the patients with PHT were retrieved. The outcomes of interest were to evaluate the clinical examination, PROMs, imaging, and isokinetic muscle strength at the baseline and last follow-up.

Results

31 patients were enrolled in the present study. Nine patients (29 % (9 of 31) described local pain at the ischial tuberosity in sitting situations and also in manual palpation. A persistent gap in the tendon string beneath the tuberosity in manual palpation was reported in 25.8 % (8 of 31). The mean VAS at the last follow-up was 2.3 ± 2.3. The mean LEFS score was 50.9 ± 18.8.Control MRI at follow-up showed scarring restitution in the proximal tendon in all patients in the partial tear group. In the complete tear group, a persisting defect state of the proximal tendon course was found in 45 % (9 of 20). The injured side achieved 81.5 ± 22.2 % of the force of the uninjured side, measured in the flexion movement at 60°/s. At an angular velocity of 240°/s, 83.2 ± 26.3 % of the force of the uninjured side was achieved.

Conclusion

According to the main findings of the present study, conservative therapy of PTH tears is associated with good clinical outcomes. High-quality investigations are required to establish the proper therapeutic algorithm and advantages of conservative management compared to a surgical approach.

Level of evidence

Level III.

Management of Proximal Hamstring Injuries: Non-operative and Operative Treatment

PURPOSE OF REVIEW

To evaluate the current evidence and literature on treatment options for proximal hamstring injuries.

RECENT FINDINGS

Patients with 3-tendon complete tears with greater than 2 cm of retraction have worse outcomes and higher complication rates compared to those with less severe injuries. Endoscopic and open proximal hamstring repair both have favorable patient reported outcomes at 5-year follow up. Proximal hamstring repair in patients who are male, with isolated semimembranosus injury, and have proximal hamstring free tendon rupture are more likely to have earlier return to sports. The Parisian Hamstring Avulsion Score (PHAS) is a validated patient-reported outcome measure to predict return to sports. Proximal hamstring injuries may occur in both elite and recreational athletes and may present with varying degrees of chronicity and severity. Injuries occur most commonly during forceful eccentric contraction of the hamstrings and often present with ischial tuberosity tenderness, ecchymosis, and hamstring weakness. Treatment decision-making is dictated by the tendons involved and chronicity. Many proximal hamstring injuries can be successfully treated with non-surgical measures. However, operative treatment of appropriately indicated proximal hamstring tendon injuries can result in significantly better functional outcomes and faster and more reliable return to sports compared to nonoperative treatment. Both endoscopic and open surgical repair techniques show high satisfaction levels and excellent patient-reported outcomes at short- and mid-term follow-up. Postoperative rehabilitation protocols vary across the literature and ongoing study is needed to clarify the optimal program, though emphasis on eccentric hamstring strengthening may be beneficial.

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.

Operative Repair of Hamstring Injuries From the Jackling Position in Rugby

Background

The jackling position within rugby has not been previously described as a mechanism for proximal hamstring injuries.

Hypothesis

Acute surgical repair of proximal hamstring avulsion injuries sustained from the jackling contact position enables a return to a previous level of sporting activity with low risk of recurrence.

Study Design

Case series; Level of evidence, 4.

Methods

This study included 54 professional rugby players (mean age, 26 ± 4.8 years) who underwent acute primary surgical repair of complete, proximal hamstring avulsion injuries. The mean follow-up time was 17 months (range, 12-24 months). Mean isometric hamstring strength and function testing was performed at 3 months and 1 year after repair.

Results

Of the 54 players, 51 (94.4%) returned to their preinjury level of sporting activity. The mean time from surgical repair to full sporting activity was 7 months (range, 4-12 months). No patients had recurrence of the primary injury. At 1 year postoperatively, patients had significantly restored mean isometric hamstring muscle strength when compared with the uninjured leg at 0° (98.4% ± 2.8%), 15° (95.9% ± 2.9%), and 45° (92.9% ± 4.1%); improved Lower Extremity Functional Score (78.0 ± 2.0); and improved Marx activity rating score (14.3 ± 1.5) (P < .001 for all).

Conclusion

Acute surgical repair of proximal hamstring avulsion injuries caused by the contact jackling position produced a high return to preinjury level of sporting activity, increased muscle strength, and improved functional outcome scores, with a low risk of recurrence at short-term follow-up.

The direct muscular origin of the semitendinosus: a pitfall in categorization of proximal hamstring tendon tears

The ischial origin of the hamstring musculature is complex. While the conjoint tendon and semimembranosus are commonly discussed and understood by radiologists, there is a lesser-known origin of the semitendinosus along the inferior and medial surface of the ischium in the form of a broad direct muscular connection. This secondary origin is infrequently described in the radiology literature and is a potential pitfall during grading of semitendinosus injuries if the interpreting physician is unaware of its presence. In a proximal hamstring tendon tear, the direct muscular origin of the semitendinosus can be spared, torn along with the conjoint tendon, or remain intact and contribute to a vertical shearing injury of the semitendinosus myotendinous junction. Detailed knowledge of this anatomy and its imaging appearance in the setting of injury enables the reader to correctly diagnose these unique hamstring injuries.

MRI findings correlate with difficult dissection during proximal hamstring repair and with postoperative sciatica

OBJECTIVE

This study examines the correlation between MRI findings and difficult dissection during proximal primary hamstring repair and postoperative sciatica.

MATERIALS AND METHODS

A total of 32 cases of surgically repaired hamstring tendon tears that underwent preoperative and postoperative MRI were divided into sciatica (n = 12) and control (n = 20) groups based on the presence or absence of postoperative sciatica. Cases were scored by two blinded musculoskeletal radiologists for imaging features associated with difficult surgical dissection and the development of subsequent sciatica. Intra- and interrater agreements, as well as correlation of MRI findings with symptoms (odds ratio, OR), were calculated.

RESULTS

On preoperative MRI, diffuse hamstring muscle edema pattern suggestive of active denervation (OR 9.4-13.6), and greater sciatic perineural scar circumference (OR 1.9-2) and length (OR 1.2-1.3) were significantly correlated with both difficult dissection and postoperative sciatica. Preoperatively, a greater number of tendons torn (OR 3.3), greater tear cross-sectional area (CSA, OR 1.03), and increased nerve T2-weighted signal (OR 3.2) and greater perineural scar thickness (OR 1.7) were also associated with difficult dissection, but not postoperative sciatica. On postoperative MRI, hamstring denervation, sciatic nerve tethering to the hamstring tendon, and development of perineural scar and greater perineural scar extent were all significantly correlated with postoperative sciatica.

CONCLUSION

Preoperative hamstring MRI demonstrates findings predictive of difficult sciatic nerve dissection; careful MRI evaluation of the nerve and for the presence and extent of perineural scar is important for preoperative planning. Preoperative and postoperative MRI both depict findings that correlate with postoperative sciatica.

Risk Factors for Rerupture After Proximal Hamstring Avulsion Injury Including the Optimal Timing for Surgery

BACKGROUND

Despite the prevalence of proximal hamstring avulsion injuries (PHAIs), the understanding of rerupture risk factors and the influence of injury chronicity on these rates remain limited.

PURPOSE

To investigate the rerupture rate after PHAI repair and identify its associated risk factors and the optimal time to primary surgery.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHOD

This is a retrospective analysis of prospectively collected data from the French Proximal Hamstring Avulsion Surgery Cohort Study targeting patients surgically treated for PHAI between 2002 and 2022. The primary outcome measure of this study was the rerupture rate of PHAI repair. The secondary outcome measures included the assessment of the potential risk factors for rerupture as well as the investigation of the incidence rate of rerupture for 100 person-years depending on various injury-surgery delay definitions.

RESULTS

This study analyzed 740 patients with a mean age of 45.9 years (SD, 13.6 years) and followed up for a mean of 4.9 years (SD, 3.9 years). The rerupture rate was 4.59% (34/740). Most reruptures (75%) occurred within the first 6 months after surgery (median, 88.5 days; interquartile range, 39.5-182 days), and 74% were atraumatic. Univariate analysis identified potential risk factors: longer initial surgery delay (hazard ratio [HR], 1.03; 95% CI, 1.01-1.04; P = .04) and initial complete ruptures (HR, 4.47; 95% CI, 1.07-18.7; P = .04). Receiver operating characteristic curve analysis found the optimal injury-surgery delay cutoff predicting rerupture to be 32 days (area under the curve, 0.62; 95% CI, 0.53-0.71). The relative Youden index was calculated at 0.24, corresponding to a sensitivity of 65% and a specificity of 59%. Surpassing this cutoff showed the highest HR (2.56), narrowest 95% CI (1.27-5.17), and highest incidence of rerupture (1.42 per 100 person-years) (P = .01). In the multivariate analysis, an injury-surgery delay of >32 days (HR, 2.5; 95% CI, 1.24-5.06; P = .01) and initial complete ruptures (HR, 4.33; 95% CI, 1.04-18.08; P = .04) emerged as significant risk factors for rerupture.

CONCLUSION

This study found a 4.59% rerupture risk after PHAI repair. Most reruptures (75%) occurred within the first 6 months after surgery. Risk factors for rerupture included chronicity and initial complete injury. The optimal threshold for chronicity of PHAI lesions, based on rerupture rate, was marked by an injury-surgery delay of >32 days.

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.

Hamstring Injuries: A Current Concepts Review: Evaluation, Nonoperative Treatment, and Surgical Decision Making

The purpose of this current concepts review is to highlight the evaluation and workup of hamstring injuries, nonoperative treatment options, and surgical decision-making based on patient presentation and injury patterns. Hamstring injuries, which are becoming increasingly recognized, affect professional and recreational athletes alike, commonly occurring after forceful eccentric contraction mechanisms. Injuries occur in the proximal tendon at the ischial tuberosity, in the muscle belly substance, or in the distal tendon insertion on the tibia or fibula. Patients may present with ecchymoses, pain, and weakness. Magnetic resonance imaging remains the gold standard for diagnosis and may help guide treatment. Treatment is dictated by the specific tendon(s) injured, tear location, severity, and chronicity. Many hamstring injuries can be successfully managed with nonoperative measures such as activity modification and physical therapy; adjuncts such as platelet-rich plasma injections are currently being investigated. Operative treatment of proximal hamstring injuries, including endoscopic or open approaches, is traditionally reserved for 2-tendon injuries with >2 cm of retraction, 3-tendon injuries, or injuries that do not improve with 6 months of nonoperative management. Acute surgical treatment of proximal hamstring injuries tends to be favorable. Distal hamstring injuries may initially be managed nonoperatively, although biceps femoris injuries are frequently managed surgically, and return to sport may be faster for semitendinosus injuries treated acutely with excision or tendon stripping in high-level athletes.

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).

A Comprehensive Review of Muscle-Tendon Junction: Structure, Function, Injury and Repair

The muscle-tendon junction (MTJ) is a highly specific tissue interface where the muscle's fascia intersects with the extracellular matrix of the tendon. The MTJ functions as the particular structure facilitating the transmission of force from contractive muscle fibers to the skeletal system, enabling movement. Considering that the MTJ is continuously exposed to constant mechanical forces during physical activity, it is susceptible to injuries. Ruptures at the MTJ often accompany damage to both tendon and muscle tissues. In this review, we attempt to provide a precise definition of the MTJ, describe its subtle structure in detail, and introduce therapeutic approaches related to MTJ tissue engineering. We hope that our detailed illustration of the MTJ and summary of the representative research achievements will help researchers gain a deeper understanding of the MTJ and inspire fresh insights and breakthroughs for future research.

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.

Surgical treatment of an old avulsion fracture of the ischial tuberosity and ischial ramus: A case report

BACKGROUND

Avulsion fracture of the ischial tuberosity is a relatively clinically rare type of trauma that is mainly incurred by adolescents during competitive sports activities. According to previous literature, the most commonly involved sports are soccer, sprinting, and gymnastics, in descending order. Dance-induced avulsion fracture of the ischial tuberosity and ischial ramus is extremely clinically rare.

CASE SUMMARY

A case of a neglected avulsion fracture of the ischial tuberosity and ischial ramus was diagnosed in a young female dancer who complained of pain and restricted movement of her right hip. She stated that she had suffered the injury while performing a split leap during a dance performance 9 mo prior. Eventually, she underwent surgery and obtained satisfactory treatment results.

CONCLUSION

Early diagnosis of these fractures is important to ensuring early proper treatment towards a quicker recovery. For old fractures with nonunion and chronic buttock pain, surgery is a preferred therapeutic choice with good treatment outcomes.

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.

Sciatic Nerve Compression after a Chronic Proximal Hamstring Tear: A Report of Two Cases and a Narrative Review of the Literature

Proximal hamstring tears are among the most common injuries afflicting athletes and middle-aged individuals. Sciatic nerve compression after a proximal hamstring injury, which can occur due to scar formation and subsequent irritation or compression of the nerve, is an infrequent but severe complication with few cases documented in the literature. No evidence is available about the optimal treatment for sciatic nerve symptoms after proximal hamstring injuries. In this case report, we present two cases involving patients primarily treated conservatively at another institution after suffering from a proximal hamstring injury and developing sciatic nerve symptoms over the course of a few months. Both were treated with open neurolysis at our institution without reattachment of the ruptured muscles to the ischial tuberosity due to the chronicity of the injuries. Both patients exhibited neurological symptoms over two years, which recovered after surgery. These two cases show that neurolysis of the sciatic nerve without reattachment of the proximal hamstring muscles is an applicable option for the treatment of chronic proximal hamstring tears with sciatic nerve compression. Further studies will be needed to validate this hypothesis.

Endoscopic Partial Proximal Hamstring Repair

The contemporary treatment of hamstring avulsions has been evolving, as more patients are being identified as having persistently symptomatic partial hamstring tears recalcitrant to nonoperative treatment. The endoscopic hamstring repair allows surgeons improved visualization of the footprint, as well as safe dissection of the sciatic nerve. The present technique article provides a step-by-step technical note to allow for safe and effective surgical treatment of partial hamstring tears.

Outcomes following adolescent athlete proximal hamstring apophyseal avulsion bone fragment excision and direct tendon-ischial tuberosity reattachment

Apophyseal proximal hamstring bone avulsion is uncommon, occurring in adolescents following sudden forceful contraction of the musculotendinous unit. It can be severely disabling, preventing return to sport. This study assessed outcome following avulsed bone excision and direct hamstring tendon-ischial tuberosity reattachment using bone anchors. Validated hamstring-specific Sydney hamstring orthopaedic research evaluation PROMs were prospectively collected from consecutively treated athletes (7 elite and 11 recreational) by a single surgeon over 13 years. Outcomes at 1-year and final follow-up for primary acute surgery at less than 3 months after injury (group 1), primary chronic surgery at more than 3 months after established nonunion (group 2) and revision following failed screw fixation (group 3) were analyzed with sport participation and level at 1 year. Sixteen primary and two revision procedures were analyzed. Mean injury age was 14.6 years (SD, 1.8). Combined primary mean injury scores improved from 11.89 (SD, 7.32) to 33.31 (SD, 2.30) and showed mean 1 year and final follow-up scores within 0.3-6.1% of preinjury values. Pronounced improvement occurred from injured scores for groups 1 versus 2, respectively at 1 year by 247.7% versus 59.0% and at final follow-up by 251.0% versus 64.1%, for groups 1 versus 2, respectively. Final outcome scores of group 3 were high. All cases returned to preinjury sport level by 1 year and indicated satisfaction to repeat treatment. No significant complications occurred. As the largest series to assess outcomes following this surgical technique, success is highlighted by high score improvements close to preinjury values and return to preinjury sport level.

Degree of Tendon Retraction and Younger Age Are Associated With Functional Decline Following Nonoperative Management of Complete Proximal Hamstring Ruptures

Purpose

To characterize functional outcomes of patients with complete proximal hamstring tendon ruptures who were treated nonoperatively and determine whether there are patient characteristics associated with unfavorable outcomes.

Methods

We retrospectively identified patients aged 18-80 (treated 1/2000-12/2019) who received nonoperative management of complete rupture of the hamstring tendon origin. Participants completed the Lower Extremity Functional Scale (LEFS), as well as Tegner Activity Scale (TAS), and a chart review was conducted to obtain demographic and medical information. Preinjury and postinjury TAS scores were compared, and additional models quantified associations between LEFS scores or changes in TAS scores (ΔTAS) and patient characteristics.

Results

Twenty-eight subjects (mean age: 61.5 ± 1.5 years; 10 male) were included. The mean follow-up time was 5.8 ± 0.8 years (range: 2-22 years). Mean preinjury and postinjury TAS scores were 5.3 ± 0.4 and 3.7 ± 0.4, respectively, with a change of 1.5 ± 0.3 (P = .0002). Degree of tendon retraction showed a negative correlation with LEFS score (P = .003) and ΔTAS (P = .005). Increased follow-up time (P = .015) and body mass index (P = .018) were associated with lower LEFS scores. Moreover, increased follow-up time (P = .002) and younger age at injury (P = .035) were associated with more negative ΔTAS. Patients classified with an American Society of Anesthesiologists (ASA) score of 2 had a median LEFS score that was 20 points (95% CI: 6.9-33.6) lower than those classified as ASA 1 (P = .015).

Conclusions

In this study, we found that increased degree of tendon retraction, increased follow-up time, and younger age at initial injury were associated with significantly worse self-reported functional outcomes.

Level of Evidence

Level IV, prognostic case series.

London International Consensus and Delphi study on hamstring injuries part 1: classification

Muscle injury classification systems for hamstring injuries have evolved to use anatomy and imaging information to aid management and prognosis. However, classification systems lack reliability and validity data and are not specific to individual hamstring muscles, potentially missing parameters vital for sport-specific and activity-specific decision making. A narrative evidence review was conducted followed by a modified Delphi study to build an international consensus on best-practice decision-making for the classification of hamstring injuries. This comprised a digital information gathering survey to a cohort of 46 international hamstring experts (sports medicine physicians, physiotherapists, surgeons, trainers and sports scientists) who were also invited to a face-to-face consensus group meeting in London . Fifteen of these expert clinicians attended to synthesise and refine statements around the management of hamstring injury. A second digital survey was sent to a wider group of 112 international experts. Acceptance was set at 70% agreement. Rounds 1 and 2 survey response rates were 35/46 (76%) and 99/112 (88.4%) of experts responding. Most commonly, experts used the British Athletics Muscle Injury Classification (BAMIC) (58%), Munich (12%) and Barcelona (6%) classification systems for hamstring injury. Issues identified to advance imaging classifications systems include: detailing individual hamstring muscles, establishing optimal use of imaging in diagnosis and classification, and testing the validity and reliability of classification systems. The most used hamstring injury classification system is the BAMIC. This consensus panel recommends hamstring injury classification systems evolve to integrate imaging and clinical parameters around: individual muscles, injury mechanism, sporting demand, functional criteria and patient-reported outcome measures. More research is needed on surgical referral and effectiveness criteria, and validity and reliability of classification systems to guide management.

London International Consensus and Delphi study on hamstring injuries part 2: operative management

The key indications for surgical repair of hamstring injuries (HSIs) remain unclear in the literature due to a lack of high-level evidence and expert knowledge. The 2020 London International Hamstring Consensus meeting aimed to highlight clear surgical indications and to create a foundation for future research. A literature review was conducted followed by a modified Delphi process, with an international expert panel. Purposive sampling was used with two rounds of online questionnaires and an intermediate round involving a consensus meeting. The initial information gathering (round 1) questionnaire was sent to 46 international experts, which comprised open-ended questions covering decision-making domains in HSI. Thematic analysis of responses outlined key domains, which were evaluated by a smaller international subgroup (n=15) comprising clinical academic sports medicine physicians, physiotherapists and orthopaedic surgeons in a consensus meeting. After group discussion of each domain, a series of consensus statements were prepared, debated and refined. A round 2 questionnaire was sent to 112 international hamstring experts to vote on these statements and determine level of agreement. The consensus threshold was set a priori at 70% agreement. Rounds 1 and 2 survey respondents were 35/46 (76%) and 99/112 (88.4%), respectively. The consensus group agreed that the indications for operative intervention included: gapping at the zone of tendinous injury (87.2% agreement) and loss of tension (70.7%); symptomatic displaced bony avulsions (72.8%); and proximal free tendon injuries with functional compromise refractory to non-operative treatment (72.2%). Other important considerations for operative intervention included: the demands of the athlete/patient and the expected functional outcome (87.1%) based on the anatomy of the injury; the risk of functional loss/performance deficit with non-operative management (72.2%); and the capacity to restore anatomy and function (87.1%). Further research is needed to determine whether surgery can reduce the risk of reinjury as consensus was not reached within the whole group (48.2%) but was agreed by surgeons (70%) in the cohort. The consensus group did not support the use of corticosteroids or endoscopic surgery without further evidence. These guidelines will help standardise treatment of HSIs, specifically the indications and decision-making for surgical intervention.

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.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40798-022-00439-6.

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.

Reconstruction of Chronic Proximal Hamstring Tear: A Novel Surgical Technique with Semitendinosus Tendon Allograft Assisted with Autologous Plasma Rich in Growth Factors (PRGF)

The reconstruction of a chronic proximal hamstring tear is a challenging pathology that posits difficulties to surgeons due to the distal retraction of the hamstring tendon stumps and the entrapment of the sciatic nerve within the scar formed around the torn hamstring tendon. We describe a novel surgical technique using a semitendinosus tendon allograft sutured in a “V inversion” manner, thereby avoiding an excess of tension and length of the new reconstructed hamstring tendons. In addition, and in order to speed up the healing process and avoid new sciatic entrapment, we assisted the surgery with liquid plasma rich in growth factors (PRGF) injected intraosseously, intratendinously and within the suture areas, as well as wrapping the sciatic nerve with a PRGF membrane. In conclusion, this novel approach offers mechanical and biological advantages to tackle the large retraction of hamstring stumps and the entrapment of the sciatic nerve within the scar.

Posttraumatic cicatricial sciatic nerve entrapment: dynamic imaging and percutaneous neurolysis

We describe a case of late-onset sciatic neuralgia due to cicatricial tethering of the sciatic nerve by a retracted torn hamstring muscle that was successfully treated with percutaneous neurolysis. Ultrasound and MRI showed a chronic complete avulsion of the proximal hamstring complex with fatty atrophy of the retracted hamstring muscles. Dynamic ultrasound and magnetic resonance imaging displayed tethering of the retracted hamstring complex to the sciatic nerve caused by cicatricial adhesions. Whereas hamstring injuries are highly prevalent sports injuries, there are only a small number of reported cases in the literature of late-onset sciatic nerve involvement. We highlight the benefits of dynamic ultrasound and magnetic resonance imaging and propose ultrasound-guided percutaneous neurolysis as a viable minimally invasive treatment option.

US and MRI of Pelvic Tendon Anatomy and Pathologic Conditions

The bony pelvis serves as the attachment site for a large number of powerful muscles and tendons that drive lower extremity movement. Organizing the pelvic tendons into groups that share a common function and anatomic location helps the radiologist systematically evaluate these structures for injury, which can be caused by repetitive stress, acute trauma, or failure of degenerated tissues. Tears of the anteromedial adductors around the pubic symphysis and anterior flexors traversing anterior to the hip principally affect younger male athletes. Tears of the lateral abductors and posterior extensors are more common in older individuals with senescent tendinosis. The deep external rotators are protected and rarely injured, although they can be impinged. Imaging of the pelvic tendons relies primarily on US and MRI; both provide high spatial and contrast resolution for soft tissues. US offers affordable point-of-care service and dynamic assessment, while MRI allows simultaneous osseous and articular evaluation and is less operator dependent. While the imaging findings of pelvic tendon injury mirror those at appendicular body sites, radiologists may be less familiar with tendon anatomy and pathologic conditions at the pelvis. The authors review pertinent anatomy and imaging considerations and illustrate common injuries affecting the pelvic tendons. Online supplemental material is available for this article. ^©RSNA, 2022.

Comparative Analysis of Patient-Reported Outcome Measures for Proximal Hamstring Injuries: A Systematic Review

Background

There is controversy regarding which patient-reported outcome measures (PROMs) should be used for proximal hamstring tendon injuries.

Hypothesis

It was hypothesized that (1) most (>50%) of the questions on the 13 most common PROMs for proximal hamstring injuries would demonstrate extensive overlap in the health domains and question categories and (2) each of the PROMs would contain a variable distribution of questions within each health domain.

Study Design

Systematic review.

Methods

We conducted a literature review through PubMed, Scopus, and CINAHL and identified the 13 most common PROMs for proximal hamstring injuries: Lower Extremity Functional Scale (LEFS), Marx activity rating scale (MARS), 12-item Short Form Survey (SF-12), Tegner activity scale (TAS), Single Assessment Numeric Evaluation (SANE), Perth Hamstring Assessment Tool (PHAT), Proximal Hamstring Injury Questionnaire (PHIQ), modified Harris Hip Score (mHHS), University of California, Los Angeles activity score (UCLA), International Hip Outcome Tool (iHOT-12), Hip Outcome Score (HOS), Sydney Hamstring Origin Rupture Evaluation (SHORE), and Non-Arthritic Hip Score (NAHS). All PROM questions were sorted into 5 health domains (pain, symptoms, activities of daily living, sports, and mindset) and further divided into question categories if they referred to similar tasks or aspects of health. Questions in the same health domain and question category were considered overlapping, and those within a health domain that did not fit into a question category were considered unique. For each PROM, we analyzed the distribution of questions within particular health domains and question categories as well as the amount of overlapping and unique questions.

Results

Of the 165 questions evaluated, 116 (70.3%) were overlapping, and 49 (29.7%) were unique. The SF-12 contained the most unique questions (9/12 [75.0%]). The MARS, TAS, SANE, and UCLA had 0 unique questions. The PHIQ and iHOT-12 contained questions in all 5 health domains. The PHAT, SHORE, and NAHS contained questions in every health domain except mindset. The LEFS, MARS, SF-12, TAS, mHHS, SANE, UCLA, and HOS contained questions in ≤3 health domains.

Conclusion

The evaluated PROMs had a high degree of overlapping questions (≥50%) and demonstrated a statistically significant variance in the distribution of questions within each health domain.

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.

Acute Proximal Hamstring Tears Can be Defined Using an Imaged-Based Classification

Purpose

To develop a clinically meaningful proximal hamstring tear classification system and to present outcome data for defined subtypes.

Methods

Retrospective review was undertaken of patients diagnosed with proximal hamstring tears at a single institution from 2012 to 2019. Images were reviewed by an orthopedic surgeon and musculoskeletal radiologist. Tears were classified as Type 1: partial with subtypes (1A, 1 cm or mild complete tear; 1B, 1-2 cm or full tear with <2 cm retraction), Type 2: complete single-tendon tears with subtypes (2c conjoint tendon only; 2s semimembranosus tendon only); or Type 3: complete tears with >2 cm retraction. Demographics, patient-reported outcome measures including Hip Outcome Score, Activities of Daily Living Subscore (HOS-ADL) and patient satisfaction were evaluated. A poor outcome was defined as HOS-ADL < 80%, and the patient acceptable symptom state (PASS) was defined as HOS-ADL 89.7%.

Results

At a mean follow-up of 38.6 (range: 12-94) months for 114 patients, distributions were as follows: 18.4% Type 1A, 19.2% Type 1B, 7.8% Type 2c, 3.5% Type 2s, and 50.9% Type 3. Intra-observer and inter-observer reliability had a mean Kappa of 0.985 (95% CI: .956, 1.01) and .905 (95% CI: .895 .915). 66 patients underwent surgery, with 68.97% of them being Type 3. The mean HOS-ADL and PASS rate were higher for operatively treated patients (95%, 93.4%) than for nonoperatively treated patients (81.86%, 44.7%). There were significantly more patients satisfied in the surgery group in both Type 1 and Type 3 tears (P = .046 and P = .049). Body mass index was a significant predictor of a poor outcome in Type 3 tears (P = .039). History of corticosteroid or PRP injection, smoking, and diabetes were not significant predictors of a poor outcome.

Conclusion

We present an MRI-based classification system for proximal hamstring injuries with both excellent intra-observer and inter-observer reliability. Outcome measures were improved in patients who underwent surgery.

Level of Evidence

IV, cohort study: diagnostic case series.

Predictive Factors Influencing Functional Results After Proximal Hamstring Tendon Avulsion Surgery: A Patient-Reported Outcome Study After 227 Operations From a Single Center

Background

Although debilitating, proximal hamstring tendon avulsion injuries are rare and often overlooked or misdiagnosed. Consequently, delayed diagnosis and surgical treatment may result in poor outcomes. Studies investigating a correlation between postoperative functional outcomes and this delay in surgical treatment or other concomitant factors in large cohorts have not yet been performed to our knowledge.

Purpose/Hypothesis

The purpose of this study was to conduct an investigation in a large patient group regarding factors that could influence a patient's functional outcome after hamstring surgery. We hypothesized that this outcome would significantly correlate to the time between trauma and surgery.

Study Design

Case series; Level of evidence, 4.

Methods

Patients who received surgical treatment of proximal hamstring tendon avulsion injuries in our institution between the years 2010 and 2020 were asked to complete a validated, injury-specific outcome measurement, the Perth Hamstring Assessment Tool (PHAT; 0-100 points). In addition to calculating these outcomes, we evaluated the association of the obtained results with possible predictive factors such as age, sex, stump retraction shown on magnetic resonance imaging (MRI), and timing and duration of surgery.

Results

A total of 226 patients (227 operations) were eligible for the study, and 204 cases of hamstring tendon avulsion injury met our inclusion criteria. The return rate for the PHAT questionnaire was 85.3%. The mean PHAT score revealed good results (79.8 ± 19.1). Irrespective of concomitant factors, the scores of male patients were significantly higher compared with those of female patients (83.8 ± 16.9 vs 75.8 ± 20.6 respectively; P = .004). The mean time to surgery was 5.7 weeks after trauma, and more delayed surgery correlated significantly with lower PHAT scores (P = .003; r = -0.228). The mean degree of stump retraction on MRI (5 cm) did not significantly influence PHAT scores (P = .525; r = -0.06).

Conclusion

Delay of surgery and female sex were disadvantageous in terms of a good functional outcome measure (PHAT score) after hamstring tendon refixation surgery. By contrast, patient age as well as the retraction of the tendon stump on preoperative MRI did not influence PHAT scores in the present study.

Avulsion injuries: an update on radiologic findings

Avulsion injuries result from the application of a tensile force to a musculoskeletal unit or ligament. Although injuries tend to occur more commonly in skeletally immature populations due to the weakness of their apophysis, adults may also be subject to avulsion fractures, particularly those with osteoporotic bones. The most common sites of avulsion injuries in adolescents and children are apophyses of the pelvis and knee. In adults, avulsion injuries commonly occur within the tendon due to underlying degeneration or tendinosis. However, any location can be involved in avulsion injuries. Radiography is the first imaging modality to diagnose avulsion injury, although advanced imaging modalities are occasionally required to identify subtle lesions or to fully delineate the extent of the injury. Ultrasonography has a high spatial resolution with a dynamic assessment potential and allows the comparison of a bone avulsion with the opposite side. Computed tomography is more sensitive for depicting a tiny osseous fragment located adjacent to the expected attachment site of a ligament, tendon, or capsule. Moreover, magnetic resonance imaging is the best imaging modality for the evaluation of soft tissue abnormalities, especially the affected muscles, tendons, and ligaments. Acute avulsion injuries usually manifest as avulsed bone fragments. In contrast, chronic injuries can easily mimic other disease processes, such as infections or neoplasms. Therefore, recognizing the vulnerable sites and characteristic imaging features of avulsion fractures would be helpful in ensuring accurate diagnosis and appropriate patient management. To this end, familiarity with musculoskeletal anatomy and mechanism of injury is necessary.

Prognosis of Incomplete Avulsion of the Proximal Hamstring Tendon Is Determined by the Avulsion Location of the Proximal Hamstring Tendon Footprint

OBJECTIVE

To test the hypothesis that prognosis of incomplete avulsion of the proximal hamstring tendon would be worse whether avulsion location reached the proximal part of the conjoined tendon (CJ) footprint or not.

DESIGN

Retrospective chart review.

SETTING

Outpatient specialty clinic.

PATIENTS

We reviewed 345 consecutive athletes with hamstring injury.

INTERVENTIONS

Based on magnetic resonance imaging, incomplete avulsion of the proximal hamstring tendon was divided into 2 cases according to avulsion location without (cases A) or with (cases B) avulsion of the proximal part of the CJ footprint.

OUTCOME MEASURES

We compared the time until return to play, subjective outcomes, and success rate of avoiding surgery between cases.

RESULTS

Incomplete avulsion of the proximal hamstring tendon was detected in 47 athletes (13.6%). Thirty-four athletes were classified as cases A, and 13 as cases B. Forty-two athletes (89.4%) were followed up until return to play. The median time from pain onset to return to play was significantly longer in cases B than in cases A (B, 39.3 weeks; A, 8.0 weeks; P = 0.00015). Subjective outcomes at return to play were significantly poorer in cases B than in cases A (P = 0.00054). Success rate of avoiding surgery were significantly poorer in cases B (55%) than in cases A (100%) (P = 0.00062).

CONCLUSIONS

Incomplete avulsion of the proximal hamstring tendon was observed in 13.6% of hamstring injuries. Return to play, subjective outcomes, and success rate of avoiding surgery were significantly poorer with avulsion of the proximal part of the CJ footprint.

Achievement of the minimal clinically important difference following open proximal hamstring repair

There is a paucity of literature on patient-reported outcome measures (PROMs) following proximal hamstring repair beyond return to play, patient satisfaction and pain improvement. The minimal clinically important difference (MCID) defines the minimum degree of quantifiable improvement that a patient can perceive, but the MCID and predictors of this measure have not been defined for this patient population. This study aimed to define the MCID and determine the efficacy of open proximal hamstring repair through achievement of MCID and identify characteristics predictive of achieving MCID. A retrospective cohort review of an institutional hip registry was conducted, analyzing the modified Harris Hip Score (mHHS) and International Hip Outcome Tool (iHOT-33). MCID was calculated using a distribution-based method. Demographic and clinical variables predictive of achieving MCID were analyzed using univariable and multivariate logistic regression analyses. Thirty-nine patients who underwent open proximal hamstring repair were included. The mean patient age was 48.5 ± 12.4 years, with a mean follow-up of 37.1 ± 28 months. The MCID was determined for each PROM (mHHS—11.8; iHOT-33—12.6). A high percentage of patients achieved MCID for both PROMs (mHHS—85.7%; iHOT-33—91.4%). Univariate logistical regression demonstrated increased age (P = 0.163), increased body mass index (BMI; P = 0.072), requirement for inpatient admission (P = 0.088) and pre-operative iHOT-33 (P = 0.104) trended towards clinically significant predictors of not achieving MCID. A high percentage of patients achieved MCID while age, BMI, inpatient admission and pre-operative iHOT-33 appear to influence the achievement of clinically significant outcome in patients undergoing open proximal hamstring repair.

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.

Delayed proximal hamstring tendon repair after ischial tuberosity apophyseal fracture in a professional volleyball athlete: a case report

Background

Ischial tuberosity apophyseal fractures are avulsion fractures of the anatomic footprint of the proximal hamstring tendons. Generally, these injuries are rare and frequently occur in skeletally immature, active patients due to incomplete ossification. Depending on the fragment displacement, non-operative or operative treatment approaches are used.

Case presentation

We report a case of a 29-year-old professional volleyball athlete who has suffered from a nonunion avulsion fracture for 14 years. Isolated suture anchor fixation was performed after open excision of a large bony fragment followed by excellent clinical and functional outcome at 1 year postoperatively.

Conclusion

In conclusion, avulsion fractures of the ischial tuberosity with large fragments and restrictions to activities of daily living due to pain can, in individualized cases, be treated with an open excision of the fragment followed by repair of the proximal hamstring tendons using suture anchors.

[Avulsion of the hamstring muscles]

BACKGROUND

Avulsion injuries of the proximal hamstring muscles are rare but very severe injuries to the dorsal thigh musculature.

OBJECTIVE

Due to improved diagnostics and experience in treatment, the decision for surgical treatment is becoming more and more frequent. Presentation of the surgical method, follow-up treatment and outcome.

MATERIAL AND METHODS

Description of the anatomy, origin, diagnostics and treatment of avulsions of the hamstring musculature.

RESULTS

Due to improvement of knowledge and diagnostics, avulsion injuries of the hamstring muscles are identified more frequently. The rapid expansion of the diagnostics, including magnetic resonance imaging (MRI) is decisive for a better identification of the extent and severity of the injury. Even if the differences in long-term results between surgical and conservative treatment are not significant in the literature, there is a clear improvement in function and resilience after surgical treatment of avulsion injuries of the hamstring muscles.

CONCLUSION

In view of the poor results of nonsurgical treatment and the clearly positive reports of surgical success, open refixation is recommended for recent proximal hamstring ruptures.

[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.

Distal avulsion of reconstituted hamstring tendons

PURPOSE

Hamstring tendon autograft (semitendinosus and gracilis) is the most commonly used graft in anterior cruciate ligament (ACL) reconstruction. Distal hamstring tendons avulsion is a rare condition, and this paper describes a previously unreported injury, local management of this rare injury pattern, and the existing literature regarding treatment options.

METHODS

Two cases are presented of distal hamstring avulsion from the tibia of reconstituted tendons, together with additional 12 cases of distal hamstrings tendon avulsion. Functional outcomes following treatment of this injury are presented, together with a literature review of management options.

RESULTS

Early surgical reattachment using suture anchor fixation was performed and excellent results were achieved in 93% of cases (13 out of 14 patients). Patient-reported outcome measures demonstrated a median Marx score 14.5 (IQR 4) and median SHORE score 34.5 (IQR 4). The mean time to surgery was 22 days (range 5-60), with mean time to return to sport at pre-injury level 5.5 months (range 2.5-12).

CONCLUSIONS

Distal hamstring tendon avulsion is a rare condition, with no consensus regarding optimal management options. Acute surgical repair leads to excellent results, with a return to pre-injury level of sporting activity.

LEVEL OF EVIDENCE

IV.

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.

Reconstruction of Chronic Proximal Hamstring Tear: Description of a Surgical Technique

While proximal hamstring tears at the myotendinous junction are common sports-related injuries that are often successfully treated nonoperatively, complete avulsions from the origin on the ischial tuberosity are less common and better treated with surgical repair to prevent significant functional limitations and ongoing weakness. The diagnosis can be easily missed, leading patients to present several months after the initial injury. In addition, some patients decide on nonoperative management initially but later present requesting surgical intervention. The delayed cases are challenging due to often significant tendon retraction, making direct repair difficult if not impossible. Techniques using allograft and autograft reconstruction have been described for this clinical situation. This Technical Note describes the use of 2 Achilles tendon allografts fixed via 5 suture anchors to reconstruct a chronic complete avulsion injury of the proximal hamstring with >5-cm retraction.

Surgical Repair of Distal Biceps Femoris Avulsion Injuries in Professional Athletes

Background

Understanding the optimal management of distal biceps femoris avulsion injuries is critical for restoring preinjury function, restoring hamstring muscle strength, increasing range of motion, and minimizing risk of complications and recurrence. Due to the rarity of these injuries, prognosis and outcomes within the literature are limited to case reports and small case series.

Purpose

To assess the effect of surgical repair for acute distal avulsion injuries of the biceps femoris tendon on (1) return to preinjury level of sporting function and (2) time to return to preinjury level of sporting function, patient satisfaction, and complications.

Study Design

Case series; Level of evidence, 4.

Methods

This prospective single-surgeon study included 22 elite athletes (18 men [82%], 4 women [18%]; mean age, 26 years; age range, 17-35 years; mean body mass index, 25.3 ± 4.1 kg/m²) undergoing primary suture anchor repair of avulsion injuries of the distal biceps femoris confirmed on preoperative magnetic resonance imaging. Predefined outcomes relating to time for return to sporting activity, patient satisfaction, complications, and injury recurrence were recorded at regular intervals after surgery. Minimum follow-up time was 12 months (range, 12.0-26.0 months) from the date of surgery.

Results

The mean time from injury to surgical intervention was 12 days (range, 2-28 days). All study patients returned to their preinjury level of sporting activity, predominately professional soccer or rugby. Mean time from surgical intervention to return to full sporting activity was 16.7 ± 8.7 weeks. At 1- and 2-year follow-up, all study patients were still participating at their preinjury level of sporting activity. There was no incidence of primary injury recurrence, and no patients required further operation to the biceps origin.

Conclusion

Surgical repair of acute avulsion injuries of the distal biceps femoris facilitated early return to preinjury level of function with low risk of recurrence, low complication rate, and high patient satisfaction in elite athletes. Suture anchor repair of these injuries should be considered a reliable treatment option in athletes with high functional demands to permit an early return to sport with restoration of hamstring strength.

Pickleball: Review and Clinical Recommendations for this Fast-growing Sport

Pickleball is a single or doubles volley sport played with paddles and ball on a hardcourt. Growing in popularity in recent years, injuries can occur similar to racquet sports; however, there is a scarcity of references in the literature for sports medicine providers encountering these athletes and injuries. This review provides clinicians treating pickleball athletes with an overview of the sport, a case study demonstrating the significant injuries that can occur in pickleball, and a review of the available literature. We provide a discussion on common pickleball injuries, injury prevention strategies, and event coverage recommendations to better equip sports medicine providers with a base of knowledge and a clinical approach to treat these athletes, or "picklers," who enjoy this fast-growing sport.

Tears of Biceps Femoris, Semimembranosus, And Semitendinosus are Not Equal-A New Individual Muscle-Tendon Concept in Athletes

Objectives:

Hamstring injuries are common and can now be accurately diagnosed. In addition, novel surgical indications have been introduced. However, evidence-based guidelines on the hamstring injuries in management of top-level athletes are missing.

Methods:

The management methods and outcomes of treatment are classically based on relatively small case series. We discuss a novel concept based on the fact that each tendon of the hamstrings muscle should be managed in an individual fashion. Furthermore, suitable indications for hamstring surgery in athletes are introduced.

Results:

The present study introduces modern treatment principles for hamstring injury management. Typical clinical and imagining findings as well as surgical treatment are presented based on a critical review of the available literature and personal experience.

Conclusions:

Hamstring injuries should not be considered to be all equal given the complexity of this anatomical region: The three separate tendons are different, and this impacts greatly on the decision-making process and outcomes in athletes.

Endoscopic Implantation of Bioinductive Patch for Chronic Partial Retearing After Hamstring Repair

Proximal hamstring tendon avulsions are a relatively rare type of hamstring injury associated with persistent morbidity, including pain, weakness, and functional limitations. Open or endoscopic surgical repair is the standard treatment for complete tendon avulsions or partial tears that remain symptomatic despite conservative management in relatively young, healthy, and active patients. However, complications known to occur include retearing of the hamstring, infection, nerve injury, inability to return to work or sport, subjective persistent weakness, and subjective persistent pain. In the case of persistent pain where the repair is partially retorn, a careful history, physical examination, and scrutiny of radiologic studies can help guide management. We describe a technique for using revision endoscopy and augmentation with a bovine bioinductive patch in a case of chronic persistently painful partial retear after a proximal hamstring repair.

Endoscopic Approach to Proximal Hamstring Avulsion Repair

Background

Endoscopic repair of a proximal hamstring avulsion promotes precise anatomical repair and lowers the risk of neurovascular injury.

Description

Indications for proximal endoscopic repair of the proximal part of the hamstrings include acute tears of 2 tendons with >2 cm of retraction in young active patients, acute complete tears of 3 tendons with >2 cm of retraction, or failed conservative treatment of tears of ≥2 tendons with ≤2 cm of retraction. Repair of a proximal hamstring avulsion is performed using 2 portals. The medial portal is developed percutaneously under fluoroscopic guidance. The lateral portal is developed under direct visualization. The footprint of the hamstrings is identified from medial to lateral. The sciatic and posterior femoral cutaneous nerves must be carefully identified and protected. The avulsed tendons are fixed with suture anchors with the knee in flexion.

Alternatives

Conservative treatment is commonly used to treat injuries of the musculotendinous junction (type 2), incomplete or complete avulsion with minimal retraction (≤2 cm) (type 3 or 4, respectively), and patients with limited mobility or severe comorbidities¹. The initial treatments consist of RICE (rest, ice, compression, and elevation), protective ambulation, and then physical therapy. Open repair is used for incomplete or complete avulsion with >2 cm of retraction, or when conservative treatments have failed^1-3. Open reconstruction is used for chronic avulsion with tendon retraction of >5 cm^4-6.

Rationale

Endoscopic surgery is a minimally invasive procedure that offers excellent visualization of the subgluteal space without gluteus maximus muscle retraction. In open repair, the inferior border of the gluteus maximus muscle is mobilized to access the ischial tuberosity. The mean distance (and standard deviation) from the inferior border of the gluteus maximus muscle to the hamstring origin has been reported to be 6.3 ± 1.3 cm, which is close to the mean distance from the inferior border of the gluteus maximus to the inferior gluteal nerve and artery, which has been reported to be 5.0 ± 0.8 cm⁷. Open repair, which requires gluteus maximus retraction, poses an injury risk to the inferior gluteal nerve and artery. Open repair increases the risk of wound infection because the incision involves the perineum⁸. The feasibility of the endoscopic repair depends on the chronicity and amount of tendon retraction. It is feasible for a symptomatic tear of ≥2 tendons with a retraction of ≤2 cm. Mobilization of the retracted tendon is challenging in endoscopic repair. In acute injuries, the degree of retraction is not critical because the tendon is easily mobilized. Chronic injuries (>2 months) and those with far tendon retraction (>5 cm) are not suitable for endoscopy⁹. In chronic injuries with incomplete or complete avulsion with minimal retraction (≤2 cm) (types 3 and 4) that have failed conservative treatment, endoscopy is suitable since the tendon is not retracted¹. Endoscopic repair can be converted to an open procedure in difficult endoscopic conditions.

Proximal hamstring tendon avulsion: state of the art

Complete proximal hamstring tendon avulsions from the ischial tuberosity, though infrequent, are the most severe type of hamstring muscle injury in the field of sport medicine. These serious injuries are commonly associated with a delayed or even misdiagnosis, despite obvious clinical findings. The published literature favours surgical repair even though the studies represent lower levels of evidence. Non-surgical treatment is a viable option for lower physical demand patients. This state-of-the-art article reviews the relevant anatomy, the clinical assessment including specific physical examination signs and diagnostic testing in patients suspected of a proximal hamstring avulsion. Up-to-date evidence is reviewed to address surgical and non-surgical treatment options and outcome assessment. The authors provide a detailed description of what would be considered the current worldwide standard of care; an open, suture-anchor-based repair of the avulsed tendon complex (semitendinosus, long head of biceps femoris and semimembranosus) securely to the ischial tuberosity. Also included are surgical tips and tricks, with advice on postsurgical management and rehabilitation. Future perspectives should involve higher quality, prospective research to better define the indications for surgery, evaluate the emerging role of endoscopic repair and disclose complications along with measuring patient-reported outcomes.

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.

Management of hamstring injuries: current concepts review

Injuries to the hamstring muscle complex are common in athletes, accounting for between 12% and 26% of all injuries sustained during sporting activities. Acute hamstring injuries often occur during sports that involve repetitive kicking or high-speed sprinting, such as American football, soccer, rugby, and athletics. They are also common in watersports, including waterskiing and surfing. Hamstring injuries can be career-threatening in elite athletes and are associated with an estimated risk of recurrence in between 14% and 63% of patients. The variability in prognosis and treatment of the different injury patterns highlights the importance of prompt diagnosis with magnetic resonance imaging (MRI) in order to classify injuries accurately and plan the appropriate management. Low-grade hamstring injuries may be treated with nonoperative measures including pain relief, eccentric lengthening exercises, and a graduated return to sport-specific activities. Nonoperative management is associated with highly variable times for convalescence and return to a pre-injury level of sporting function. Nonoperative management of high-grade hamstring injuries is associated with poor return to baseline function, residual muscle weakness and a high-risk of recurrence. Proximal hamstring avulsion injuries, high-grade musculotendinous tears, and chronic injuries with persistent weakness or functional compromise require surgical repair to enable return to a pre-injury level of sporting function and minimize the risk of recurrent injury. This article reviews the optimal diagnostic imaging methods and common classification systems used to guide the treatment of hamstring injuries. In addition, the indications and outcomes for both nonoperative and operative treatment are analyzed to provide an evidence-based management framework for these patients. Cite this article: Bone Joint J 2020;102-B(10):1281-1288.

The surgical repair of proximal hamstring avulsions

Aims

Despite the increase in the surgical repair of proximal hamstring tears, there exists a lack of consensus in the optimal timing for surgery. There is also disagreement on how partial tears managed surgically compare with complete tears repaired surgically. This study aims to compare the mid-term functional outcomes in, and operating time required for, complete and partial proximal hamstring avulsions, that are repaired both acutely and chronically.

Methods

This is a prospective series of 156 proximal hamstring surgical repairs, with a mean age of 48.9 years (21.5 to 78). Functional outcomes were assessed preinjury, preoperatively, and postoperatively (six months and minimum three years) using the Sydney Hamstring Origin Rupture Evaluation (SHORE) score. Operating time was recorded for every patient.

Results

Overall, significant improvements in SHORE scores were seen at both six months and mid-term follow-up. Preoperatively, acute patients (median score 27.1 (interquartile range (IQR) 22.9)) reported significantly poorer SHORE scores than chronic patients (median score 42.9 (IQR 22.1); p < 0.001). However, this difference was not maintained postoperatively. For partial tears, acutely repaired patients reported significantly lower preoperative SHORE scores compared to chronically reapired partial tears (median score 24.3 (IQR 15.7) vs median score 40.0 (IQR 25.0); p < 0.001) but also significantly higher SHORE scores at six-month follow-up compared to chronically repaired partial tears (median score 92.9 (IQR 10.7) vs. median score 82.9 (IQR 14.3); p < 0.001). For complete tears, there was only a difference in preoperative SHORE scores between acute and chronic groups. Overall, acute repairs had a significantly shorter operating time (mean 64.67 minutes (standard deviation (SD) 12.99)) compared to chronic repairs (mean 74.71 minutes (SD = 12.0); t = 5.12, p < 0.001).

Conclusion

Surgical repair of proximal hamstring avulsions successfully improves patient reported functional outcomes in the majority of patients, irrespective of the timing of their surgery or injury classification. However, reducing the time from injury to surgery is associated with greater improvement in patient outcomes and an increased likelihood of returning to preinjury functional status. Acute repair appears to be a technically less complex procedure, as indicated by reduced operating times, postoperative neurological symptoms and number of patients requiring bracing. Acute repair is therefore a preference among many surgeons. Cite this article: Bone Joint J 2020;102-B(10):1419–1427.

Does Time From Injury to Surgery Affect Outcomes After Surgical Repair of Partial and Complete Proximal Hamstring Ruptures?

Background

No previous study has compared the outcomes of repair for partial and complete proximal hamstring ruptures at various intervals after the injury.

Purpose

The primary aim was to determine whether time from injury to surgery affected outcomes after primary repair of partial and complete proximal hamstring ruptures. The secondary aim was to assess patients' experiences from initial evaluation to finding a treating surgeon.

Study Design

Cohort study; Level of evidence, 3.

Methods

Records from 2007 to 2016 from a single surgeon's practice were reviewed. A total of 124 proximal hamstring repair procedures in 121 patients were identified. There were 92 patients who completed questionnaires: a custom survey, the standard Lower Extremity Functional Scale (LEFS), a custom LEFS, the standard Marx activity scale, a custom Marx activity scale, and the University of California Los Angeles (UCLA) activity score. Results were analyzed for partial and complete repair procedures performed at ≤3 weeks, ≤6 weeks, and >6 weeks after the injury.

Results

The mean follow-up was 43 months (median, 38 months). Of 93 repair procedures reviewed, 51% (9/28 partial; 38/65 complete), 79% (16/28 partial; 57/65 complete), and 22% (12/28 partial; 8/65 complete) were performed at ≤3 weeks, ≤6 weeks, and >6 weeks, respectively. At those various intervals, no statistical difference was found in standard LEFS, custom LEFS, standard Marx, custom Marx, or UCLA scores. Female sex, older age, and body mass index >30 kg/m² were negative predictors of outcome measures. When repaired >6 weeks after the injury, a greater percentage of patients reported weakness of the operative leg compared with the contralateral side (partial tears: 6.3% vs 25%, respectively; complete tears: 24.6% vs 50%, respectively) in addition to greater sitting intolerance (partial tears: 0% vs 25%, respectively; complete tears: 7.1% vs 12.5%, respectively). Patients repaired >6 weeks after the injury visited, on average, 2.6 practitioners before an evaluation by the treating surgeon compared with 1.6 treated surgically at ≤6 weeks (P = .008).

Conclusion

Patients with proximal hamstring repair performed in the acute and chronic settings can expect successful outcomes but may experience more subjective weakness and difficulty with prolonged sitting when the repair is performed >6 weeks after the injury. Patients faced challenges in receiving the correct diagnosis and referral to an appropriate treating surgeon, emphasizing the need for an increased awareness of the injury.