MRI characteristics of adductor longus lesions in professional football players and prognostic factors for return to play

Outcomes of Activity-Related Lower Extremity Muscle Tears After Application of the British Athletics Muscle Injury Classification: A Systematic Review

CONTEXT

Muscle injury classification and grading systems have been reported for >100 years; yet it offer limited evidence relating the clinical or radiological qualities of a muscle injury to the pathology or clinical outcome. The British Athletics Muscle Injury Classification (BAMIC) incorporates recent predictive features of muscle injuries and provides a precise radiographic framework for clinical prediction and management.

OBJECTIVE

To investigate clinical outcomes, particularly time to return to play (RTP), reinjury rate (RIR), and prognostic value of specific magnetic resonance imaging (MRI) findings, of activity-related muscle injuries (tears) in athletes after application of the BAMIC.

DATA SOURCES

A search of PubMed (NLM), EMBASE (Ovid), Web of Science (Clarivate), Cochrane Library (Wiley), and ClinicalTrials.gov from the inception date of each database through August 31, 2022, was conducted. Keywords included the BAMIC.

STUDY SELECTION

All English language studies evaluating clinical outcomes of RTP and RIR after activity-related muscle injuries and where BAMIC was applied were included. A total of 136 articles were identified, and 11 studies met inclusion criteria.

STUDY DESIGN

Systematic review (PROSPERO: CRD42022353801).

LEVEL OF EVIDENCE

Level 2.

DATA EXTRACTION

Two reviewers independently screened studies for eligibility and extracted data. Methodological quality of included study was assessed independently by 2 reviewers with the Newcastle-Ottawa Quality Scale (NOS); 11 good quality studies (4 prospective cohort studies, 7 retrospective cohort studies) with 468 athletes (57 female) and 574 muscle injuries were included.

RESULTS

All studies reported a statistically significant relationship between BAMIC grade, BAMIC injury site, and/or combined BAMIC grade and injury site with RTP. A statistically significant increased RIR was reported by BAMIC grade and BAMIC injury site in 2 of 4 and 3 of 4 studies, respectively. The prognostic value of individual MRI criteria was limited.

CONCLUSION

Consistent evidence suggests that BAMIC offers prognostic and therapeutic guidance for clinical outcomes, particularly RTP and RIR, after activity-related muscle injuries in athletes that may be superior to previous muscle injury classification and grading systems.

Muscle Healing in Sports Injuries: MRI Findings and Proposed Classification Based on a Single Institutional Experience and Clinical Observation

MRI plays a crucial role in assessment of patients with muscle injuries. The healing process of these injuries has been studied in depth from the pathophysiologic and histologic points of view and divided into destruction, repair, and remodeling phases, but the MRI findings of these phases have not been fully described, to our knowledge. On the basis of results from 310 MRI studies, including both basal and follow-up studies, in 128 athletes with muscle tears including their clinical evolution, the authors review MRI findings in muscle healing and propose a practical imaging classification based on morphology and signal intensity that correlates with histologic changes. The proposed phases, which can overlap, are destruction (phase 1), showing myoconnective tissue discontinuity and featherlike edema; repair (phase 2), showing filling in of the connective tissue gaps by a hypertrophic immature scar; and remodeling (phase 3), showing scar maturation and regression of the edema. A final healed stage can be identified with MRI, which is characterized by persistence of a slight fusiform thickening of the connective tissue. This information can be obtained from a truncated MRI protocol with three acquisitions, preferably performed with a 3-T magnet. During MRI follow-up of muscle injuries, other important features to be assessed are changes in muscle edema and specific warning signs, such as persistent intermuscular edema, new connective tear, and scar rupture. An understanding of the MRI appearance of normal and abnormal muscle healing and warning signs, along with cooperation with a multidisciplinary team, enable optimization of return to play for the injured athlete. ©RSNA, 2024 See the invited commentary by Flores in this issue.

Adductor longus and brevis lesion in an amateur soccer player: platelet rich plasma and multifractioned hyaluronic acid injections to enhance clinical recovery

Groin pain is a common issue in athletes, with a particularly high incidence in male soccer players. Adductor muscles are the most involved site of the groin, accounting for up to one-fourth of muscle injuries of that region. Physical therapy and rehabilitation programs for adductor-related groin pain using active exercises are effective in getting athletes back to sport. However, the return-to-play time varies according to the injury severity. Minor lesions can recover in 1-2 weeks, while severer injuries require 8-12 weeks. To enhance tendon healing and shorten the return to play time, intrandentinous injections of Platelet Rich Plasma (PRP) have been proposed. An increasing body of evidence in literature have shown efficacy of platelet rich plasma in aiding the healing process in tendinopathies. Similarly, more recent evidences have proven hyaluronic (HA) acid to have anti-inflammatory, proliferative, repairing, and analgesic effects. This case report presents the clinical application of combined PRP and a multifractioned (a mixture of different molecular weights) HA in a 24-year-old athlete suffering from a hip adductor rupture.

Acute Adductor Muscle Injury: A Systematic Review on Diagnostic Imaging, Treatment, and Prevention

BACKGROUND

Controversies remain regarding the diagnosis, imaging, and treatment of acute adductor injuries in athletes.

PURPOSE

To investigate the diagnostic imaging, treatment, and prevention of acute adductor injuries based on the most recent and relevant scientific evidence.

STUDY DESIGN

Systematic review; Level of evidence, 4.

METHODS

The PubMed and Web of Science databases were searched according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines to identify articles studying acute adductor injury in athletes. Inclusion criteria were original publication on acute adductor injury in amateur or professional athletes, level 1 to 4 evidence, mean patient age >15 years, and results presented as return-to-sport, pain, or functional outcomes. Quality assessment was performed with the CONSORT (Consolidated Standards of Reporting Trials) statement or the methodological index for non-randomized studies criteria. Articles were grouped as imaging, treatment, prevention focused, or mixed.

RESULTS

A total of 30 studies published between 2001 and 2021 were selected, involving 594 male patients with a mean age 26.2 years (range, 16-68 years). The most frequent sports were soccer (62%), basketball (14%), futsal (6%), American football (3%), and ice hockey and handball (2%). Risk factors for acute adductor injury were previous acute groin injury, adductor weakness compared with the uninjured side, any injury in the previous season, and reduced rotational hip range of motion. The frequency of complete adductor muscle tears on magnetic resonance imaging was 21% to 25%. For complete adductor tears, the average time to return to play was 8.9 weeks in patients treated nonoperatively and 14.2 weeks for patients treated surgically. Greater stump retraction was observed in individuals treated surgically. Partial acute adductor tears were treated nonoperatively with physical therapy in all studies in the present systematic review. The average time to return to play was 1 to 6.9 weeks depending on the injury grade. The efficacy of adductor strengthening on preventing acute adductor tears has controversial results in the literature.

CONCLUSION

Athletes with partial adductor injuries returned to play 1 to 7 weeks after injury with physical therapy treatment. Nonoperative or surgical treatment is an acceptable option for complete adductor longus tendon tear.

Isolated adductor longus avulsion in a young semi-professional football player: Imaging contribution and therapeutic considerations

Adductor longus injuries are usually observed at the proximal musculo-tendinous junction, but isolated tendinous ruptures (i.e., avulsion) at the origin on the pubic bone are uncommon. In this article, we report a new case of isolated adductor longus avulsion that occurred in a young athlete and was treated with conservative therapy. An 18 years old semi-professional football player, in the attempt to reach the ball with his right leg, reported acute pain and functional limitation in his left adductor area. Clinical examination showed tenderness on palpation associated with mild swelling. Manual strength testing of adductor muscles showed weakness and elicited moderate pain in the proximal groin region near the pubic bone. The diagnostic evaluations (ultrasound [3-14 MHz linear probe] and magnetic resonance imaging [1.5 Tesla magnetic field]), performed a few days after the event, showed a complete isolated avulsion of the proximal adductor longus tendon associated with a fluid collection, with a gap of about 9.5 mm from its insertion on the pubic bone. Degenerative alterations (sub-chondral sclerosis, bone edema, erosions, cortical irregularities, calcifications) were found. These findings were crucial in the treatment choice because conservative management is suggested when the gap is below 1 cm and when no important displacement of proximal torn tendon's end at dynamic ultrasound is appreciated. A structured rehabilitation protocol was implemented, allowing the player to come back to his full athletic activity after 146 days. Return to play was allowed when several subjective and objective parameters were fully satisfied (full hip range of motion, pain-free football-specific activities, less than a 5%-10% difference in hip adduction strength between the injured and uninjured legs, advanced anatomical healing of the adductor longus tendon seen on diagnostic exams, and Hip And Groin Outcome Score [HAGOS] scores similar to baseline data). This case report emphasizes the importance of diagnostic imaging and clinical assessments in the management of an adductor longus avulsion with short retraction (about 1 cm). Both imaging techniques are non-invasive and without risks, allow contra-lateral examination and may guide in the treatment choice; moreover, they significantly influence the post-care approach by enabling to fine-tune a safe return to full athletic activity with minor re-injury rate. While US can be used as primary imaging modality, MRI offers a higher level of accuracy.

The Assessment, Management and Prevention of Calf Muscle Strain Injuries: A Qualitative Study of the Practices and Perspectives of 20 Expert Sports Clinicians

Background

Despite calf muscle strain injuries (CMSI) being problematic in many sports, there is a dearth of research to guide clinicians dealing with these injuries. The aim of this study was to evaluate the current practices and perspectives of a select group of international experts regarding the assessment, management and prevention of CMSI using in-depth semi-structured interviews.

Results

Twenty expert clinicians working in elite sport and/or clinician-researchers specialising in the field completed interviews. A number of key points emerged from the interviews. Characteristics of CMSI were considered unique compared to other muscle strains. Rigor in the clinical approach clarifies the diagnosis, whereas ongoing monitoring of calf capacity and responses to loading exposure provides the most accurate estimate of prognosis. Athlete intrinsic characteristics, injury factors and sport demands shaped rehabilitation across six management phases, which were guided by key principles to optimise performance at return to play (RTP) while avoiding subsequent injury or recurrence. To prevent CMSI, periodic monitoring is common, but practices vary and data are collected to inform load-management and exercise selection rather than predict future CMSI. A universal injury prevention program for CMSI may not exist. Instead, individualised strategies should reflect athlete intrinsic characteristics and sport demands.

Conclusions

Information provided by experts enabled a recommended approach to clinically evaluate CMSI to be outlined, highlighting the injury characteristics considered most important for diagnosis and prognosis. Principles for optimal management after CMSI were also identified, which involved a systematic approach to rehabilitation and the RTP decision. Although CMSI were reportedly difficult to prevent, on- and off-field strategies were implemented by experts to mitigate risk, particularly in susceptible athletes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40798-021-00364-0.

Time to return to full training and recurrence of rectus femoris injuries in elite track and field athletes 2010-2019; a 9-year study using the British Athletics Muscle Injury Classification

Rectus femoris (RF) injuries are common in sports requiring maximal acceleration and sprinting. The British Athletics Muscle Injury Classification (BAMIC) describes acute muscle injury based on the anatomical site of injury and has been associated with return to play in hamstring and calf muscle injury. The aim of this study was to describe and compare the time to return to full training (TRFT) and injury recurrence for BAMIC-classified RF injuries sustained by elite track and field (T&F) athletes over a 9-year period. All rectus femoris injuries sustained by elite T&F athletes on the British Athletics World Class Program between September 2010 and September 2019 that were investigated with an MRI within 7 days of acute onset anterior thigh pain were included. Injuries were graded from the MRI by a specialist musculoskeletal radiologist using the BAMIC, and TRFT and injury recurrence were determined by evaluation of the Electronic Medical Record. Athlete demographics and World Athletics event discipline were recorded. Specific injury details including mechanism, location of injury, and whether surgical or rehabilitation management was undertaken were recorded. There were 38 RF injuries in 27 athletes (24.7 ± 2.3 years; 10 male, 17 female). Average TRFT for rehabilitation managed cases was 20.4 ± 14.8 days. Grade 1 injuries had significantly shorter TRFT compared with grades 2 (p = 0.04) and 3 (p = 0.01). Intratendinous (c) and surgically managed RF injuries each had significantly longer TRFT compared with other injury classes (p < 0.001). Myofascial (a) injuries had reduced repeat injury rates compared with b or c classes (p = 0.048). Grade 3 injuries had an increased repeat injury rate compared with other grades (p = 0.02). There were 4 complete (4c) proximal free tendon injuries sustained during sprinting and all in female athletes. The average TRFT for RF injuries in elite T&F is similar to that previously identified in elite football and Australian Rules. Similar to previous research in hamstring and calf injury, RF injuries extending into the tendon (BAMIC class c) had delayed TRFT which may reflect the longer duration required for tendon healing and adaptation. Grade 3 injuries had in increased repeat injury rate compared with grades 1 and 2. The BAMIC diagnostic framework may provide useful information for clinicians managing rectus femoris injuries in T&F.

A 4-year study of hamstring injury outcomes in elite track and field using the British Athletics rehabilitation approach

OBJECTIVES

The British Athletics Muscle Injury Classification (BAMIC) correlates with return to play in muscle injury. The aim of this study was to examine hamstring injury diagnoses and outcomes within elite track and field athletes following implementation of the British Athletics hamstring rehabilitation approach.

METHODS

All hamstring injuries sustained by elite track and field athletes on the British Athletics World Class Programme between December 2015 and November 2019 that underwent an MRI and had British Athletics medical team prescribed rehabilitation were included. Athlete demographics and specific injury details, including mechanism of injury, self-reported gait phase, MRI characteristics and time to return to full training (TRFT) were contemporaneously recorded.

RESULTS

70 hamstring injuries in 46 athletes (24 women and 22 men, 24.6±3.7 years) were included. BAMIC grade and the intratendon c classification correlated with increased TRFT. Mean TRFT was 18.6 days for the entire cohort. Mean TRFT for intratendon classifications was 34±7 days (2c) and 48±17 days (3c). The overall reinjury rate was 2.9% and no reinjuries were sustained in the intratendon classifications. MRI variables of length and cross-sectional (CSA) area of muscle oedema, CSA of tendon injury and loss of tendon tension were associated with TRFT. Longitudinal length of tendon injury, in the intratendon classes, was not associated with TRFT.

CONCLUSION

The application of BAMIC to inform hamstring rehabilitation in British Athletics results in low reinjury rates and favourable TRFT following hamstring injury. The key MRI variables associated with longer recovery are length and CSA of muscle oedema, CSA of tendon injury and loss of tendon tension.

Surgical versus conservative management of traumatic proximal adductor longus avulsion injuries: A systematic review

BACKGROUND

Proximal avulsion injuries of the adductor longus have been managed both conservatively and operatively with good clinical outcomes, but there is no consensus on which option yields the best results. Thus, the present study aimed to review the available literature, comparing the outcomes and the time to return to sports with different management options.

MATERIAL AND METHODS

This study was conducted according to the PRISMA statement. The literature search was conducted in September 2020. All the clinical trials investigating the management of traumatic proximal adductor longus avulsion injuries were considered for inclusion. Only studies reporting data from athletes were considered. The outcomes of interest were the time to return to sport and return to preinjury activity level.

RESULTS

Data from 46 patients were retrieved. The mean follow-up was 24.6 ± 23.8 months. The study population was represented by male athletes with a mean age of 30.0 ± 4.8. Mean stump retraction was 3.3 ± 0.6 cm in the surgical and 1.7 ± 0.6 in the conservative cohort (P = 0.07). The rate of patients returning to prior activity level was similar in the two groups, but surgically treated patients required a longer time to return to sport (3.9 ± 1.5 months vs. 2.2 ± 1.0 months, P = 0.0001).

CONCLUSION

Conservative management for traumatic avulsion of the proximal adductor longus insertion may produce shorter time to return to sport. Both conservative and operative strategies allowed to achieve similar pre-injury activity level.

LEVEL OF EVIDENCE

IV, systematic review.

Return to Play and Recurrence After Calf Muscle Strain Injuries in Elite Australian Football Players

BACKGROUND

Calf muscle strain injuries (CMSI) are prevalent in sport, but information about factors associated with time to return to play (RTP) and recurrence is limited.

PURPOSE

To determine whether clinical and magnetic resonance imaging (MRI) data are associated with RTP and recurrence after CMSI.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

Data of 149 CMSI reported to the Soft Tissue injury Registry of the Australian Football League were explored to evaluate the impact of clinical data and index injury MRI findings on RTP and recurrence. Clinical data included age, previous injury history, ethnicity, and the mechanism of injury.

RESULTS

Irrespective of the anatomical location, players with CMSI with severe aponeurotic disruption (AD) took longer to RTP than players with CMSI with no AD: 31.3 ± 12.6 days vs 19.4 ± 10.8 days (mean ± SD; P = .003). A running-related mechanism of injury was associated with a longer RTP period for CMSI overall (adjusted hazard ratio [AHR], 0.59; P = .02). The presence of AD was associated with a longer RTP period for soleus injuries (AHR, 0.6; P = .025). Early recurrence (ie, ≤2 months of the index injury) was associated with older age (AHR, 1.3; P = .001) and a history of ankle injury (AHR, 3.9; P = .032). Older age (AHR, 1.1; P = .013) and a history of CMSI (AHR, 6.7; P = .002) increased the risk of recurrence within 2 seasons. The index injury MRI findings were not associated with risk of recurrence.

CONCLUSION

A running-related mechanism of injury and the presence of AD on MRI were associated with a longer RTP period. Clinical rather than MRI data best indicate the risk of recurrent CMSI.

Adductor injuries in the National Basketball Association: an analysis of return to play and player performance from 2010 to 2019

Objectives: 1) To evaluate return to play (RTP) timing in National Basketball Association (NBA) athletes following adductor injuries, and 2) to evaluate the effect of adductor injuries on player performance, game availability, and career longevity following RTP. Methods: Adductor injuries in NBA athletes from the 2009-2010 to 2018-2019 seasons were identified utilizing publicly available records via previously validated methodology. RTP time was calculated, and player performance and game availability were compared pre- vs. post-injury. Additionally, an injury-free control group matched for age, BMI, position, and experience was assembled to allow for comparisons in performance, availability, and career length. Results: In total, 79 adductor injuries across 65 NBA athletes were identified. The average injured player was 28.3 ± 4.0 years of age, and had 6.5 ± 4.2 seasons of NBA experience. Guards were injured more frequently than forwards or centers (49% vs 25% vs 25%, respectively). All players were able to RTP following first-time adductor injury after missing an average of 7.7 ± 9.8 games (median [IQR]: 4 [1-9]) and 16.9 ± 20.4 days (median [IQR]: 9 [3.5-20]). Twelve players (18.5%) suffered an adductor re-injury at a mean latency of 509.5 ± 503.9 days. Adductor injuries did not result in significant changes in any major statistical category (points, assists, rebounds, steals, blocks, turnovers, field goal percentage), player efficiency rating (PER), minutes/game, games/season, or a number of all-star selections (all P > 0.05) following RTP. Additionally, when compared to matched controls, no difference was found in pre- to post-injury change of PER, games/season, or minutes/game (all P > 0.05). Career longevity was not significantly different between groups (P = 0.44). Conclusion: Following adductor injury, NBA players returned to gameplay after missing an average of 16 to 17 days, or 7 to 8 games. Adductor injury did not affect player performance, nor game availability or career longevity.

Return to Sport After Criteria-Based Rehabilitation of Acute Adductor Injuries in Male Athletes: A Prospective Cohort Study

Background:

Despite being one of the most common sports injuries, there are no criteria-based rehabilitation programs published for acute adductor injuries.

Purpose:

To evaluate return-to-sport (RTS) outcomes and reinjuries after criteria-based rehabilitation for athletes with acute adductor injuries.

Study Design:

Cohort study; Level of evidence, 2.

Methods:

Male adult athletes with an acute adductor injury underwent a supervised, standardized criteria-based exercise rehabilitation program. Magnetic resonance imaging (MRI) was used to grade the injury extent from 0 (negative finding) to 3 (complete tear/avulsion). There were 3 milestones used to evaluate the RTS continuum: (1) clinically pain-free, (2) completion of controlled sports training, and (3) return to full team training. Subsequent injuries were registered within the first year.

Results:

We included 81 athletes with an acute adductor injury (MRI grade 0: n = 14; grade 1: n = 20; grade 2: n = 30; grade 3: n = 17). Of these, 61 (75%) athletes achieved RTS milestone 1, 50 (62%) achieved RTS milestone 2, and 75 (93%) achieved RTS milestone 3. There were no statistical differences in the RTS duration between MRI grade 0, 1, and 2 at any RTS milestone; thus, these were grouped together as grade 0-2. The median time (interquartile range [IQR]) for athletes with grade 0-2 injuries to become clinically pain-free was 13 days (IQR, 11-21 days), to complete controlled sports training was 17 days (IQR, 15-27 days), and to return to full team training was 18 days (IQR, 14-27 days). For athletes with a grade 3 injury, median times were 55 days (IQR, 31-75 days), 68 days (IQR, 51-84 days), and 78 days (IQR, 68-98 days), respectively. The overall 1-year reinjury rate was 8%. Athletes who achieved RTS milestone 1 had a statistically significantly lower reinjury rate than athletes who did not (5% vs 21%, respectively; ϕ = –0.233; P = .048). Athletes who achieved RTS milestone 2 had a nonstatistically significantly lower reinjury rate than athletes who did not (6% vs 13%, respectively; ϕ = –0.107; P = .366).

Conclusion:

We analyzed the results of a criteria-based rehabilitation protocol for athletes with acute adductor injuries. Athletes with an MRI grade 0-2 adductor injury were clinically pain-free after approximately 2 weeks and returned to full team training after approximately 3 weeks. Most athletes with an MRI grade 3 adductor injury were pain-free and returned to full team training within 3 months. Meeting the clinically pain-free criteria resulted in fewer reinjuries compared with not meeting the criteria.