Original Research Isolated Adductor Magnus Injuries in Athletes A Case Series Sandra Mechó,*†‡§ MD, Ramon Balius,k MD, PhD, Mireia Bossy,{#** MD, Xavier Valle,‡§†† MD, Carles Pedret,# MD, PhD, Ángel Ruiz-Cotorro,‡‡§§ MD, PhD, and Gil Rodas,‡kk{{ MD, PhD Investigation performed at the Catalan Sports Council, Government of Catalonia, Barcelona, Spain Background: Little is known about injuries to the adductor magnus (AM) muscle and how to manage them. Purpose: To describe the injury mechanisms of the AM and its histoarchitecture, clinical characteristics, and imaging features in elite athletes. Study Design: Case series; Level of evidence, 4. Methods: A total of 11 competitive athletes with an AM injury were included in the study. Each case was clinically assessed, and the diagnosis and classification were made by magnetic resonance imaging (MRI) according to the British Athletics Muscle Injury Classification (BAMIC) and mechanism, location, grade, and reinjury (MLG-R) classification. A 1-year follow-up was performed, and return-to-play (RTP) time was recorded. Results: Different mechanisms of injury were found; most of the athletes (10/11) had flexion and internal rotation of the hip with extension or slight flexion of the knee. Symptoms consisted of pain in the posteromedial (7/11) or medial (4/11) thigh during adduction and flexion of the knee. Clinically, there was a suspicion of an injury to the AM in only 3 athletes. According to MRI, 5 lesions were located in the ischiocondylar portion (3 in the proximal and 2 in the distal myoconnective junction) and 6 in the pubofemoral portion (4 in the distal and 2 in the proximal myoconnective junction). Most of the ischiocondylar lesions were myotendinous (3/5), and most of the pubofemoral lesions were myofascial (5/6). The BAMIC and MLG-R classification coincided in distinguishing injuries of moderate and mild severity. The management was nonoperative in all cases. The mean RTP time was 14 days (range, 0-35 days) and was longer in the ischiocondylar cases than in the pubofemoral cases (21 vs 8 days, respectively). Only 1 recurrence, at <10 months, was recorded. Conclusion: Posteromedial thigh pain after an eccentric contraction during forced adduction of the thigh from hip internal rotation should raise a suspicion of AM lesions. The identification of the affected portion was possible on MRI. An injury in the ischiocondylar portion entailed a longer RTP time than an injury in the pubofemoral portion. Keywords: adductor magnus injury; BAMIC and MLG-R classification; hip; MRI; pelvis; thigh Adductor complex injuries account for 10% to 16% of other adductor muscles are practically anecdotal in the injuries in sports with frequent eccentric loads, particularly literature.1,26,37 Indeed, there are very few published soccer.7,18,24 This muscle group is the second group most studies that refer to isolated injuries of the adductor likely to be injured in these sports, accounting for 20% to magnus (AM) muscle.12,17,21,23,30 25% of all muscle injuries.7 After the Doha agreement,35 lesions to the adductor mus- ANATOMY AND FUNCTION OF THE AM cle group were included in the category of causes of groin pain, specifically adductor-related groin pain (ARGP).11 The AM is a complex muscle with a triangular appearance With ARGP, the most commonly injured muscle is the that is located in the medial and posterior compartments of adductor longus (AL) at the level of the proximal or distal the thigh and is part of the adductor muscles of the hip. It is musculotendinous junction (MTJ).30 However, the litera- located next to the adductor brevis in a plane deep to the ture focuses more frequently on lesions that affect the muscular wall formed by the pectineus, the AL, and the AL insertion because of their controversial and optional gracilis. After the gluteus maximus, it is the heaviest mus- surgical treatment. 4,6,28,29 References to injuries to cle with the largest cross-sectional area of the lower extremity.14,33 The Orthopaedic Journal of Sports Medicine, 11(1), 23259671221138806 The AM is divided into an adductor (pubofemoral) por- DOI: 10.1177/23259671221138806 tion and an ischiocondylar portion15,25 (Figure 1). The for- ª The Author(s) 2023 mer is innervated by the obturator nerve, whereas the This open-access article is published and distributed under the Creative Commons Attribution - NonCommercial - No Derivatives License (https://creativecommons.org/ licenses/by-nc-nd/4.0/), which permits the noncommercial use, distribution, and reproduction of the article in any medium, provided the original author and source are credited. You may not alter, transform, or build upon this article without the permission of the Author(s). For article reuse guidelines, please visit SAGE’s website at http://www.sagepub.com/journals-permissions. 1 2 Mechó et al The Orthopaedic Journal of Sports Medicine Figure 1. Diagrams of (A) anterior and (B) posterior views of the adductor magnus, showing the pubofemoral (a) and Figure 2. (A) Diagram of the insertions of the pubofemoral ischiocondylar (b) portions. portion (blue) and ischiocondylar portion (red) of the adductor magnus (AM) in the ischiopubic ramus and ischial tuberosity latter is innervated by the sciatic nerve. The pubofemoral as well as the hamstring (green) in the ischial tuberosity. portion originates proximally from the inferior pubic ramus (B) Diagram of the lateral view of the AM, demonstrating the and ischial ramus, while the ischiocondylar portion has its pubofemoral (a) and ischiocondylar (b) portions. origin lateral to the pubofemoral portion and inferior and medial to the conjoint and semimembranosus tendons of the hamstring25 (Figure 2). tuberosity to the adductor tubercle on the medial femoral The most proximal pubofemoral fibers follow a more hori- condyle and through fibrous attachments to the supracondy- zontal direction and can be defined as the smaller and ante- lar line of the femur. rior portion of the muscle called the adductor minimus.15 The This complex structure allows us to identify, in the AM, a distal attachment of the adductor portion reaches the linea proximal MTJ and a distal MTJ of the adductor portion as aspera and blends with the proximal attachment of the short well as a proximal MTJ and a distal MTJ of the ischiocondy- head of the biceps femoris muscle. This combination of the lar portion. Both portions of the AM are adductors of the adductor portion and the short head of the biceps femoris thigh; however, the pubofemoral portion is also a hip flexor allows the 2 muscles to work in a coordinated manner as (mainly at the expense of more proximal fibers), and the stabilizers of the femur and pelvis.15 ischiocondylar portion is also a hip extensor (when the hip The ischiocondylar or hamstring portion of the AM is so is in maximum flexion). These functions diminish as the hip named because of its similarity in structure, proximal inser- approaches neutral positions.19 These 2 portions of the mus- tion, and common innervation to the hamstring muscles.15,32 cle also work synergistically during the gait cycle and control It is nearly vertical in orientation, extending from the ischial the pelvis for postural stabilization. *Address correspondence to Sandra Mechó, MD, Department of Radiology, Hospital of Barcelona, Avinguda Diagonal 660, 08034 Barcelona, Spain (email: mechomeca@gmail.com) (Twitter: @mechomeca). † Department of Radiology, Hospital of Barcelona, Barcelona, Spain. ‡ Medical Department, Football Club Barcelona, Barcelona, Spain. § Department of Surgery and Orthopedics, Autonomous University of Barcelona, Barcelona, Spain. k Catalan Sports Council, Government of Catalonia, Barcelona, Spain. { Clı́nica Creu Blanca, Barcelona, Spain. # Sports Medicine and Imaging Department, Clı́nica Diagonal, Barcelona, Spain. **Quiron Hospital, Barcelona, Spain. †† Dexeus University Hospital, Barcelona, Spain. ‡‡ Royal Spanish Tennis Federation, Barcelona, Spain. §§ Clı́nica Mapfre de Medicina del Tenis, Barcelona, Spain. kk Barça Innovation Hub, Football Club Barcelona, Barcelona, Spain. {{ Sports Medicine Unit, Sant Joan de Déu Hospital, Barcelona, Spain. Final revision submitted September 10, 2022; accepted September 13, 2022. The authors declared that there are no conflicts of interest in the authorship and publication of this contribution. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto. Ethical approval for this study was obtained from the Catalan Sports Council (No. 042/CEICGC/2021). The Orthopaedic Journal of Sports Medicine Adductor Magnus Injuries in Athletes 3 According to Jeno and Schindler,15 the AM can be com- the adductors to allow the weight of gravity to release the pared with the deltoid muscle: although its function as a explored muscles in each stretch. whole is to adduct the thigh, a part flexes it and functions as Each assisted stretch was compared with that of the con- a medial rotator, while the other extends it and acts as a tralateral limb to assess the limitations of the injured limb’s side rotator. Thus, on one hand, the most superior segment range of motion. We also performed isometric, concentric, of the pubofemoral portion (along with the fibers from the and eccentric maneuvers of the main muscle groups, espe- short head of the biceps femoris) focuses its main activity on cially the hamstring and adductors (adductor squeeze test). pelvic stabilization15; on the other hand, the rest of the For the squeeze test, the hip joint was maintained at 45 of muscle, with longer fibers, performs thigh mobilization flexion, and the knee joint was at 90 of flexion. In this activities through its lever arm.32 position, assisted by a clinician, the patient performed an In this work, we wanted to examine our experience of isometric contraction and reported the area of pain.5 In all AM injuries and their different locations in a group of cases, a diagnosis of an AM injury was made and included athletes without ruling out causal relationships with other in our analysis. factors. Therefore, the purpose of our study was to present our series of isolated tears of the AM in high-level athletes. We hypothesized that an AM injury presents with pain not MRI Assessment only in the medial aspect of the thigh but also in the poster- MRI was performed after the injury. Except for the first 3 omedial aspect; by using magnetic resonance imaging (MRI), patients, MRI was conducted on a 3-T Vantage Titan (Canon we can define which portion of the AM (pubofemoral or ischio- Medical Systems) using various sequences: axial, sagittal, condylar) is injured and which injuries in the ischiocondylar and coronal T2-weighted fat-saturated images (repetition portion portend a longer return-to-play (RTP) time. time, 5200, 5000, and 3700 ms; echo time, 44-60 ms; slice thick- ness, 2.5-3.5 mm; field of view, 256  256, 192  272, and 288  320 mm) and axial and coronal T1-weighted turbo spin echo METHODS images (repetition time, 900-980 ms; echo time, 11 ms; slice thickness, 2.5-3.5 mm; field of view, 352  352 and 288  Participants 320 mm). For muscle MRI, it is recommended to perform Included were high-level athletes who were diagnosed with fluid-sensitive sequences (T2-weighted in our case) with an an AM injury between October 2011 and February 2021. intermediate TE (eg, <65 ms) to obtain adequate contrast and The protocol for this study was approved by the ethics com- spatial resolution of connective tissue.8,13 mittee for clinical research of the Catalan Sports Council, A radiologist with 12 years of experience in musculoskel- and written informed consent was obtained from all etal MRI (S.M.) and a physician with 6 years of experience included participants. in musculoskeletal MRI (M.B.) independently reviewed and The study athletes were aged 18 to 36 years and partici- evaluated the MRI scans and categorized the lesions in pated in competitive sports. We included athletes who pre- relation to their histoarchitecture and the affected MTJ.31 sented with pain in the medial or posteromedial aspect of the They also recorded the existence of previous scars in the thigh during their sports activity (training or matches) and AM, the loss of tension and loss of pennation angle, and the had MRI scans that confirmed an AM injury within 4 days of presence of a hematoma. Each lesion was classified accord- the injury. We excluded all injuries to the AM caused by ing to 2 systems: the British Athletics Muscle Injury Clas- direct trauma (eg, racket contusion, kick, hit by a pitch). sification (BAMIC)27 and the mechanism, location, grade, Characteristics recorded included athlete age, weight, and reinjury (MLG-R) classification developed by the Foot- height, sport, laterality, affected limb, limb dominance, ball Club Barcelona–Aspetar–Duke University34 (Figure 3). thigh aspect affected and mechanism of injury. Limb dom- In cases of a discrepancy between the 2 observers, the inance was indicated by the hand or foot body segment that images were reviewed by the observers and 2 physicians performs the function of support or impulse in movement in with more than 30 years of experience in muscle injury which force, dexterity, or precision is required.2 imaging (R.B., G.R.) until a consensus was reached. Clinical Examination Treatment, RTP Time, and Reinjury Evaluation A clinical examination was performed by 3 physicians Gradual RTP was instituted under the supervision of 3 (R.B., X.V., Á.R-C.), each with more than 20 years of expe- physicians (R.B., X.V., Á.R-C.). All injured athletes under- rience in sports medicine. The examination consisted of went a standardized rehabilitation program inspired by the palpation of the affected area to localize the pain and iden- rehabilitation protocol of hamstring injuries.9,20 The reha- tify its level (proximal, middle, or distal third of the thigh) bilitation program was divided into 4 phases: and the affected part of the thigh (medial, posterior, or posteromedial). In all cases, we performed assisted passive 1. Acute phase: gait normalization and rest-ice-compres- stretching of both the adductor and the hamstring muscles. sion-elevation. Stretching was led fully by the physician so that the patient 2. Range of motion and strength phase: painless recovery was able to relax his or her body in the position. We per- of range of motion, starting with concentric training formed hip flexion for the hamstring and hip adduction for and progressing to eccentric training. 4 Mechó et al The Orthopaedic Journal of Sports Medicine BAMIC Gradel 0 (a/b) Imaging normal/patchy edema Grade 1a (myofascial), 1b (myotendinous) <10% CSA; <5 cm of length Grade 2a (myofascial), 2b (myotendinous) 10%-50% CSA; 5-15 cm of length; fiber disruption 1-5 cm Grade 2c (tendinous) <50% tendinous CSA; <5 cm of length Grade 3a (myofascial), 3b (myotendinous) >50% CSA; >15 cm of length; fiber disruption >5 cm Grade 3c (tendinous) >50% tendinous CSA; <5 cm of length Grade 4c Complete tear MLG-R Classification Mechanism of injury (M) I = indirect; T = direct Location (L) Muscle portion: First letter: muscle portion P = proximal; M = middle; D = distal Subscript: MTJ injured MTJ injured: P = proximal; D = distal Example: Injury at the proximal portion of the AM and affecting the proximal MTJ = PP Grading of severity (G) 0 = negative MRI Superscript r indicates tendon tissue affected 1 = interstitial edema 2 =¼interstitial edema or peritendinous edema with minor muscle fiber architectural distortion ± minor intermuscular hemorrhage, no gap 3 = any quantifiable gap between fibers Example: MRI shows a distal myotendinous injury of the ischiocondylar portion with tendinous quantifiable tear =¼3r Number of muscle reinjuries (R) 0 = first episode; 1 = first reinjury; 2 = second reinjury a AM, adductor magnus; BAMIC, British Athletics Muscle Injury Classification; CSA, cross-sectional area; MLG-R, mechanism, location, grade, Figureand reinjury;27MRI, 3. BAMIC and magnetic MLG-R34resonance imaging; MTJ, Injury Classification myotendinous Systems. a junction. 3. Functional phase: controlled lower extremity loading ensuring good hydration and nutrition of the athlete. The and return to running activities, sport-specific training RTP time was recorded, and an update on reinjuries was and agility exercises (service games for tennis players performed through a telephone interview (November to and explosive runs and jumps for the rest of the ath- December 2021). letes), and plyometric training. 4. RTP phase: When the patient completed the rehabil- itation process, he or she began training on RESULTS the playing surface (individual sports) or with the team. The decision of RTP was made when there Participants was little chance of a reinjury. Objective criteria A total of 11 athletes with a diagnosed AM injury were were used such as a clinical and physical examina- included in the study. Patient data are provided in Table 1. tion without any limitations and functional criteria Overall, 6 athletes were high-level tennis players (all such as an isokinetic strength test. ranked within the top 100 players of the Association of Tennis Professionals or the Women’s Tennis Association), Athletes needed to be pain-free before they could progress 3 were professional soccer players, 1 was a professional shot to the next phase. Treatment with nonsteroidal anti- putter, and 1 was a professional fencer. Most athletes were inflammatory drugs was not performed in any patient, and right-handed (82%); however, the more affected limb was treatment with local injections was not necessary in any the left (73%). The nondominant leg was involved in 6 of the patient. The duration of each phase varied according to the 11 patients. severity of the injury and the response of the athlete. Fur- Various mechanisms of injury were recorded. In most thermore, care was taken to avoid detraining during the patients, the injury occurred acutely during an opening of rehabilitation period by engaging in cardiovascular fitness, the limbs, either under loading (patients 1, 2, and 10) or maintaining motor control skills when possible, and during a slide on the playing surface (patients 6, 7, 9, and The Orthopaedic Journal of Sports Medicine Adductor Magnus Injuries in Athletes 5 TABLE 1 in the ischiocondylar portion, of which 3 affected the prox- Characteristics of Study Athletes (N ¼ 11)a imal myoconnective junction (Figure 4) and 2 affected the distal myoconnective junction (Figures 5 and 6), and 6 were Value located in the pubofemoral portion, of which 2 affected the Age, y 24 ± 5 (18-31) proximal myoconnective junction (Figure 7) and 4 affected Height, cm 1.8 ± 0.1 (162-194) the distal myoconnective junction (Figure 8). The ischiocon- Weight, kg 74.0 ± 7.8 (58-85) dylar lesions had greater involvement of the myotendinous Body mass index 22.7 ± 0.8 (21.6-24.7) connective structure, while the pubofemoral lesions mainly Sex had myofascial involvement. In 3 patients with ischiocon- Female 4 (36.4) dylar lesions, there was an alteration in tendon tension, Male 7 (63.6) which never occurred with pubofemoral injuries. In all Sport except patient 3, there was an alteration in the pennation Tennis 6 (54.5) angle. Of the 5 instances in which a clear hematoma was Soccer 3 (27.3) Shot put 1 (9.1) observed, 3 injuries were localized in the ischiocondylar Fencing 1 (9.1) portion and 2 in the pubofemoral portion. Limb dominance The MRI reviewers only presented a discrepancy in 1 Right 9 (81.8) patient (patient 5; see Figure 6). The large hematoma made Left 2 (18.2) it difficult to rule out the loss of tension in the distal tendon Affected limb of the ischiocondylar portion. After a discussion with the Right 3 (27.3) most experienced physicians, it was ruled out. Left 8 (72.7) Affected aspect of thigh Medial 4 (36.4) Treatment, RTP Time, and Reinjury Evaluation Posteromedial 7 (63.6) Injury mechanism In all athletes, the management was nonsurgical. Except Slide on playing surface 4 (36.4) in 2 patients (patients 3 and 10), an initial rest from Loading 3 (27.3) sports of 48 hours and the application of ice were pre- Tennis serve 3 (27.3) Progressive pain 1 (9.1) scribed. All the athletes passed the rehabilitation phases without difficulty. In patient 5, during the acute phase, a Data are reported as mean ± SD (range) or n (%). crutches were used. The mean RTP time was 14 days (range, 0-35 days), as shown in Table 3. Specifically, a 11). In 3 tennis players (patients 4, 5, and 8), the mecha- mean RTP time of 21 days (range, 6-35 days) was reported nism of injury was the end of the service motion, just at the for ischiocondylar injuries, whereas pubofemoral injuries moment of placing the ipsilateral limb on the ground. In the had a mean RTP time of 8 days (range, 0-19 days). case of sliding, it was affected the contralateral limb. Through a telephone survey of the athletes, we identified Finally, patient 3 had progressive tenderness of the medial a single case of recurrence in a year (patient 8). This rein- aspect of the thigh during training sessions and soccer jury required an RTP time of 3 weeks . matches for 1 week. DISCUSSION Clinical Examination The major finding of this series of 11 AM lesions was that In 7 patients, pain was located at the posteromedial there are 2 types of strain injuries of the AM: in the ischio- aspect of the thigh, while in 4 patients, it was located at condylar portion or the pubofemoral portion. The mecha- the medial aspect. In 5 patients, pain was located in the nism of injury was flexion and internal rotation of the hip middle third; in 4 patients, it was proximal; and in 2 with extension of the knee. Symptoms consisted of pain in patients, the location was broader, affecting the proximal the posteromedial or medial aspect of the thigh. The ath- and middle areas. Most athletes presented with pain in letes returned to sports at 2 to 3 weeks after the injury, but both adduction and flexion of the knee. The squeeze test an ischiocondylar injury had a longer RTP time than a pub- findings at full knee extension (180 ) and at 90 of knee ofemoral one. flexion were positive for the entire sample. With this explo- The AM has an important role in stabilizing the hip and ration, the clinician guided the diagnosis toward a ham- pelvis in hip flexion positions.19 This occurs during sports- string strain in 5 patients, an AL injury in 3 patients, and specific actions such as lateral sliding on the playing an AM rupture in the remaining 3 patients. With these surface with the extremities open in flexion and internal suspected diagnoses, MRI was requested. rotation of the hip or opening of the thigh under loading. In all but 1 patient (patient 3), injuries occurred when the hip MRI Assessment was in flexion and the knee was in internal rotation with extension or slight flexion. These situations occurred at the The main MRI findings are presented in Table 2. AM inju- end of a tennis serve (3 patients), during a lateral slide on ries were diagnosed via MRI in all athletes: 5 were located the playing surface (3 in tennis and 1 in fencing), or while 6 Mechó et al The Orthopaedic Journal of Sports Medicine TABLE 2 MRI Findings and RTP Timesa Anatomic and Histoarchitecture Findings Injury Classification Anatomic MTJ Loss of Loss of RTP Patient Sport Portion Affected Involved Tension Pennation Angle Hematoma Fibrosis/Scar BAMIC MLG-R Time, d 1 Soccer Pubofemoral Distal No Yes No No 1a I Pd 3 0 8 2 Shot put Ischiocondylar Distal Yes Yes No No 2b I Dd 3r 0 6 3 Soccer Pubofemoral Proximal No No No No 1a I Pp 2 0 0 4 Tennis Ischiocondylar Proximal Yes Yes No Yes 2c I Pp 3r 0 17 5 Tennis Ischiocondylar Distal No Yes Yes No 3a I Md 3 0 25 6 Tennis Pubofemoral Distal No Yes Yes No 2a I Pd 3 0 19 7 Tennis Pubofemoral Distal No Yes Yes No 2b I Pd 3 0 10 8 Tennis Ischiocondylar Proximal Yes Yes Yes No 2c I Pp 3r 0 35 9 Tennis Pubofemoral Proximal No Yes No No 2a I Mp 3 0 10 10 Soccer Pubofemoral Distal No Yes No No 1a I Pd 3 0 3 11 Fencing Ischiocondylar Proximal No Yes Yes No 2b I Pp 3 0 21 a BAMIC, British Athletics Muscle Injury Classification; MLG-R, mechanism, location, grade, and reinjury; MRI, magnetic resonance imaging; MTJ, myotendinous junction; RTP, return to play. Figure 5. Shot putter (patient 2) with a distal myotendinous injury of the ischiocondylar portion. (A) Sagittal and (B) axial Figure 4. Tennis player (patient 4) with a proximal tendinous T2-weighted fat-saturated magnetic resonance imaging of tear- injury of the ischiocondylar portion. (A) Coronal and (B) axial ing of the distal musculotendinous junction (arrowhead), with the T2-weighted fat-saturated magnetic resonance imaging of loss of pennation angle and interstitial and intermuscular edema. scarring on the proximal tendon of the ischiocondylar portion Injury rating: I Dd 3r 0 (according to MLG-R classification) and 2b (arrowheads). Injury rating: I Pp 3r 0 (according to MLG-R (according to British Athletics Muscle Injury Classification). classification) and 2c (according to British Athletics Muscle Injury Classification). gluteus maximus,19 and most likely, this is the specific posi- tion responsible for isolated AM injuries during the tennis service motion. load bearing with the thighs open (2 in soccer and 1 in AM lesions should not be considered solely in the case of shot put). groin pain, but they may have more distal involvement, Of the 11 patients, 6 were tennis players of a very high with pain in the posteromedial or medial aspect of the level who were injured during the service motion or while thigh. In a study of 111 adductor injuries, Serner et al30 sliding on the playing surface. In the case of serving, the identified the following distribution: 62 were in the AL, affected limb was ipsilateral, whereas in the case of sliding, 18 in the adductor brevis, 17 in the pectineus, 9 in the it was contralateral. The sliding injuries mainly occurred obturator externus, 4 in the gracilis, and only 1 in the on a clay tennis court, where this type of movement is com- AM. The study by Serner et al only counted adductor inju- mon. Injuries that occurred during serves were ischiocon- ries with groin pain; therefore, they only found 1 patient dylar, while the ones that occurred while sliding were with an AM injury. pubofemoral. The injuries during serves occurred in the In 5 patients, the injury affected the ischiocondylar por- ipsilateral extremity at the end of the gesture, when the tion; in 4 of them, the initial diagnosis (after a clinical eval- hip was flexed and internally rotated and the player initi- uation) was a hamstring strain. Because the AM shares ated extension. In this position, the hip extensor moment of common innervation and actions with the major hamstring the AM is more effective than that of the hamstring or tendons, this structure is considered to be part of the The Orthopaedic Journal of Sports Medicine Adductor Magnus Injuries in Athletes 7 Figure 6. Tennis player (patient 5) with a distal myofascial injury of the ischiocondylar portion. (A) Coronal and (B) axial T2-weighted fat-saturated magnetic resonance imaging (MRI) of an extensive hematoma (arrowheads), with the surrounding fibers displaced and interstitial edema (arrows). (C) Short-axis view of ultrasound with the corresponding MRI section and (D) panoramic view of ultra- sound. Injury rating: I Md 3 0 (according to MLG-R classification) and 3a (according to British Athletics Muscle Injury Classification). Figure 7. Soccer player (patient 3) with a proximal myofascial injury of the pubofemoral portion. (A) Coronal and (B) axial Figure 8. Soccer player (patient 1) with a distal myofascial injury T2-weighted fat-saturated magnetic resonance imaging of of the pubofemoral portion. (A) Sagittal and (B) axial T2-weighted blurred muscle fibers and mild intermuscular edema. Injury fat-saturated magnetic resonance imaging of tearing of the distal rating: I Pp 2 0 (according to MLG-R classification) and 1a musculotendinous junction (arrowhead), with the loss of penna- (according to British Athletics Muscle Injury Classification). tion angle and interstitial and intermuscular edema. Injury rating: I Pd 3 0 (according to MLG-R classification) and 1a (according to British Athletics Muscle Injury Classification). hamstring muscle complex16,22,25; therefore, Broski et al3 called it the “mini-hamstring.” Moreover, it has been described that in 6% of the cases of complete avulsion of the recreational athletes. In recreational athletes, this injury is hamstring, there is an associated detachment of the ischio- probably underdiagnosed. In our opinion, ultrasound has condylar portion of the AM.3 Probably because of this, it is become an essential tool in sports medicine care. In most relatively easy to confuse an AM injury with a hamstring consultations for muscle injuries, ultrasound is performed injury. In addition, as AM lesions do not generally present as the first diagnostic method. In the future, better knowl- with severe symptoms, MRI is not performed, and they are edge of the anatomy may lead to the better utilization of erroneously classified as hamstring injuries. In the series ultrasound and, with it, a better diagnosis of this injury, presented, as athletes were professional, MRI was quickly even in recreational athletes. performed. A diagnosis of this type of injury is more fre- As was mentioned previously, AM injuries could be quently made initially by MRI, which is an imaging tech- observed and localized in the pubofemoral or ischiocondylar nique that is not usually the first diagnostic step in cases of portion. In 6 patients, the lesion was located in the 8 Mechó et al The Orthopaedic Journal of Sports Medicine pubofemoral portion. In previous literature, only Kuhlmann an eccentric contraction during forced adduction of the et al17 described an AM rupture with involvement of the thigh from hip internal rotation should raise a suspicion pubofemoral portion. Once the injury was identified by loca- of AM lesions. Using MRI, we can identify properly the tion in the correct muscle and portion, it was assessed with portion affected. An injury in the ischiocondylar portion the BAMIC27: 7 of 11 patients had grade 2 (moderate) inju- entailed a longer RTP time than an injury in the pubofe- ries, and 3 of 11 had grade 1 (small) injuries. Regarding the moral portion. location (site), 3 of 11 were myotendinous (“b”), and 6 of 11 were myofascial (“a”). Similar observations were made by using the MLG-R classification.34 In this case, most injuries REFERENCES (8/11) were located in the proximal third of the muscle, being easily confused for injuries that affect the proximal third of 1. Attarian DE. Isolated acute hip adductor brevis strain. J South Orthop the hamstring. Although they were located in the proximal Assoc. 2000;9(3):213-215. third, the subscript “d,” corresponding to the distal MTJ, was 2. Ballestero E, Duran C, Planas A, López Bedoya J, Vernetta M. Fuerza y dominancia lateral. Apunts Sports Med. 1997;1(47):74-80. recorded in 6 of 11 cases. In 4 of these cases, the subscript 3. Broski SM, Murthy NS, Krych AJ, Obey MR, Collins MS. The adductor “d” involved the pubofemoral portion. Anatomically, these magnus “mini-hamstring”: MRI appearance and potential pitfalls. injuries were located further away from the proximal origin Skeletal Radiol. 2016;45(2):213-219. of the muscle and in the thickness of the muscular body. In 4. Chopra A, Robinson P. Imaging athletic groin pain. Radiol Clin North 10 of 11 patients, injuries were classified as grade 3, which Am. 2016;54(5):865-873. suggests structural lesions with a distortion of the architec- 5. Delahunt E, Kennelly C, McEntee BL, Coughlan GF, Green BS. The ture of 11% to 25% of the cross-sectional area and thus con- thigh adductor squeeze test: 45 of hip flexion as the optimal test position for eliciting adductor muscle activity and maximum pressure sidered moderate or small lesions according to the BAMIC. values. Man Ther. 2011;16(5):476-480. Injuries that comprise ARGP have a mean RTP time of 6. Dimitrakopoulou A, Schilders EM, Talbot JC, Bismil Q. Acute avulsion about 14 days, which represents approximately half the of the fibrocartilage origin of the adductor longus in professional soc- recovery time of pubic-related groin pain or inguinal- cer players: a report of two cases. Clin J Sport Med. 2008;18:167-169. related groin pain.10,36 In our series, the mean RTP time 7. Ekstrand J, Hägglund M, Waldén M. Epidemiology of muscle injuries in was 14 days, similar to the RTP time of ARGP. Although professional football (soccer). Am J Sports Med. 2011;39(6):1226-1232. the number of patients was small and reliable statistical 8. Ekstrand J, Healy JC, Waldén M, Lee JC, English B, Hägglund M. Hamstring muscle injuries in professional football: the correlation of analysis could not be performed, the mean RTP time of MRI findings with return to play. Br J Sports Med. 2012;46:112-117. ischiocondylar injuries was clearly longer than the mean 9. Futbol Club Barcelona Medical Services. Clinical practice guide for RTP time of pubofemoral injuries: 21 versus 8 days, respec- muscle injuries: epidemiology, diagnosis, treatment and prevention. tively. One explanation for this difference is that injuries of Version 4.5. Apunts Sports Med. 2009;164:179-203. the ischiocondylar portion had more myotendinous connec- 10. Hallén A, Ekstrand J. Return to play following muscle injuries in pro- tive structures affected than those of the pubofemoral por- fessional footballers. J Sports Sci. 2014;32(13):1229-1236. tion, which affected myofascial structures. 11. Heijboer WMP, Weir A, Delahunt E, et al. A Delphi survey and inter- national e-survey evaluating the Doha agreement meeting classifica- Lesions involving the AM are usually well tolerated in our tion system in groin pain: where are we 5 years later? J Sci Med Sport. experience, and perhaps for this reason, they are underdiag- 2022;25(1):3-8. nosed. In our series, patient 4 showed a scar in the proximal 12. Iqbal A, Kalia S, Beale D, James SL, Botchu R. Isolated distal adduc- tendon of the ischiocondylar portion (Figure 4). This athlete tor magnus tendon avulsion as a rare cause of medial knee pain: a reported discomfort during the service motion a few weeks case report. Indian J Radiol Imaging. 2020;30(4):507-509. before the medical consultation, but the symptoms were well 13. Isern-Kebschull J, Mechó S, Pruna R, et al. Sports-related lower limb tolerated. We assumed that the scar was from an injury that muscle injuries: pattern recognition approach and MRI review. Insights Imaging. 2020;11:108. had occurred during the period of discomfort. Moreover, the 14. Ito J, Moriyama H, Inokuchi S, Goto N. Human lower limb muscles: an telephone interview only registered 1 case of a reinjury evaluation of weight and fiber size. Okajimas Folia Anat Jpn. 2003; (patient 8) that was resolved in 3 weeks and without any 80(2-3):47-55. sequelae. 15. Jeno SH, Schindler GS. Anatomy, bony pelvis and lower limb, thigh adductor magnus muscles. In: StatPearls. NCBI Bookshelf. Stat- Limitations Pearls Publishing; 2020:1-4. 16. Koulouris G, Connell D. Hamstring muscle complex: an imaging review. Radiographics. 2005;25(3):571-586. The main limitations of this study are the small number of 17. Kuhlmann JN, Kirsch JM, Mimoun M, Baux S. Traumatic rupture of patients and its retrospective design. Nevertheless, this is the great adductor (adductor magnus): apropos of a case. Article in the first study presenting a series of AM injuries in athletes French. Rev Chir Orthop Reparatrice Appar Mot. 1986;72:317-319. and describing 2 types of them—ischiocondylar and pubo- 18. Lynch SA, Renstrom PA. Groin injuries in sport: treatment strategies. femoral—on the basis of the complex anatomic structure of Sports Med. 1999;28:137-144. this muscle. 19. Mallac C. Adductor magnus: tales of tightness. Sports Injury Bulletin. Accessed February 20, 2021. https://www.sportsinjurybulletin.com/ anatomy/anatomy/adductor-magnus-tales-of-tightness 20. Malliaropoulos N, Papalexandris S, Papalada A, Papacostas E. The CONCLUSION role of stretching in rehabilitation of hamstring injuries: 80 athletes follow-up. Med Sci Sports Exerc. 2004;36(5):756-759. Sports medicine specialists and team physicians should be 21. Martin T, Louis R, Corinne B, Antoine L, Nathan D. Spontaneous hip more aware of AM injuries. Posteromedial thigh pain after adductor haematoma. J Pediatr Surg Case Rep. 2020;60:101568. The Orthopaedic Journal of Sports Medicine Adductor Magnus Injuries in Athletes 9 22. Martini F, Timmons MJ, Tallitsch RB. Human Anatomy. Pearson 31. Study Group of the Muscle and Tendon System from the Spanish Benjamin Cummings; 2012. Society of Sports Traumatology; Balius R, Blasi M, Pedret C, et al. 23. McNeilan RJ, Rose M, Mei-Dan O, Genuario J. Open repair of acute A histoarchitectural approach to skeletal muscle injury: searching for proximal adductor magnus avulsion. Arthrosc Tech. 2018;8(1):e75-e80. a common nomenclature. Orthop J Sports Med. 2020;8(3): 24. Nielsen AB, Yde J. Epidemiology and traumatology of injuries in soc- 2325967120909090. cer. Am J Sports Med. 1989;17:803-807. 32. Takizawa M, Suzuki D, Ito H, Fujimiya M, Uchiyama E. The adductor 25. Obey MR, Broski SM, Spinner RJ, Collins MS, Krych AJ. Anatomy of part of the adductor magnus is innervated by both obturator and the adductor magnus origin: implications for proximal hamstring sciatic nerves. Clin Anat. 2014;27:778-782. injuries. Orthop J Sports Med. 2016;4(1):2325967115625055. 33. Takizawa M, Suzuki D, Ito H, Fujimiya M, Uchiyama E. Why adductor 26. Pedret C, Balius R, Barceló P, et al. Isolated tears of the gracilis magnus muscle is large: the function based on muscle morphology in muscle. Am J Sports Med. 2011;39(5):1077-1080. cadavers. Scand J Med Sci Sports. 2012;24(1):197-203. 27. Pollock N, James SL, Lee JC, Chakraverty R. British Athletics Muscle 34. Valle X, Alentorn-Geli E, Tol JL, et al. Muscle injuries in sports: a new Injury Classification: a new grading system. Br J Sports Med. 2014; evidence-informed and expert consensus-based classification with 48(18):1347-1351. clinical application. Sports Med. 2017;47(7):1241-1253. 28. Schilders E, Bismil Q, Robinson P, O’Connor PJ, Gibbon WW, Talbot 35. Weir A, Brukner P, Delahunt E, et al. Doha agreement meeting on JC. Adductor-related groin pain in competitive athletes: role of terminology and definitions in groin pain in athletes. Br J Sports Med. adductor enthesis, magnetic resonance imaging, and entheseal pubic 2015;48:768-774. cleft injections. J Bone Joint Surg Am. 2007;89(10):2173-2178. 36. Werner J, Hägglund M, Ekstrand J, Waldén M. Hip and groin time-loss 29. Schlegel TF, Bushnell BD, Godfrey J, Boublik M. Success of nonop- injuries decreased slightly but injury burden remained constant in erative management of adductor longus tendon ruptures in National men’s professional football: the 15-year prospective UEFA Elite Club Football League athletes. Am J Sports Med. 2009;37:1394-1399. Injury Study. Br J Sports Med. 2019;53(9):539-546. 30. Serner A, Weir A, Tol JL, et al. Characteristics of acute groin injuries in 37. Wong-On M, Turmo-Garuz A, Arriaza R, et al. Injuries of the obturator the hip flexor muscles: a detailed MRI study in athletes. Scand J Med muscles in professional soccer players. Knee Surg Sports Traumatol Sci Sports. 2018;28(2):677-685. Arthrosc. 2018;26(7):1936-1942.