Case Report: Athletic Pubalgia and Core Injury. Tear/Detachment of the Right Common Adductor Longus-Rectus Abdominis Aponeurosis

Clinical Orthopedic Imaging

Coley C. Gatlin, M.D.; Charles P. Ho, Ph.D., M.D.

Steadman Philippon Research Institute, Vail, CO, USA

History of present illness left anterior hip impingement sign, patient’s right lower abdominal/groin and negative bilateral hip posterior pain, there is an acute injury superim- The patient is a 24-year-old male impingement testing. Negative bilat- posed upon chronic right groin skier who sustained a crash resulting eral hip log roll testing. Also, he symptoms. in acute injuries to his left knee and noted mild lower abdominal pain right groin/lower abdomen. The with sit-ups. patient complained of left knee pain, Differential diagnosis for swelling, and instability. After his groin pain (limited) Radiographs crash, he was unable to ski down due • Rectus abdominis muscle strain to a giving out sensation in his right AP pelvis and right hip radiographs hip/groin. He also noted right lower were obtained. No acute pelvic frac- • Adductor muscle strain, tear, and/or abdominal pain and groin pain and ture is identified. There was bilateral chronic tendinopathy described a pinching sensation along hip decreased offset at the head and • Rectus abdominis – adductor longus his right hip and groin. The patient neck junction. No evidence of hetero- aponeurosis tear had a chronic history of right lower topic ossification or avulsion fracture abdominal/groin pain dating back at the adductor origins. • Pelvic bone fracture / stress fracture approximately 1.5 years prior to the • Acute labral tear acute injury. Clinical assessment • Apophysitis Physical examination 24-year-old male skier who sustained • Inguinal Hernia (indirect and direct) acute injuries to the right lower He was noted on physical exam with abdomen/groin and left knee. Injuries • Femoral Acetabular Impingement tenderness to palpation along the to the left knee based on physical (FAI) origin of the adductors. He had pain exam and MRI include a complete • Iliopsoas tendinitis with resisted hip adduction and hip ACL tear, lateral meniscus tear, and flexion. He had a positive right ante- MCL sprain. In reference to the • Iliotibial band syndrome rior hip impingement sign, negative

1A 1B 1C

1 Sequential coronal STIR images (large FOV) from anterior to posterior (1A-C) demonstrating edema and hemorrhage in the right adductors (*), stripping/undermining of the common adductor longus-rectus abdominis aponeurosis (white arrow), and avulsion of the adductor longus from the pubic symphysis (blue arrow).

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Plan 2A 2B At the patient’s initial presentation, it was determined that the patient would require left knee surgery to repair his ACL and lateral meniscus. In reference to his right lower abdominal/groin pain, the treatment options included conservative treatment versus conservative therapy and obtaining additional diagnostic imaging studies. After discussion with the patient, additional MR imaging of the pubic symphysis and right hip was performed to further assess the degree of injury and narrow the treatment options.

MR imaging findings 2 Coronal proton density TSE FS images of the right hip (small FOV) showing adductor interstitial strain/edema (*), stripping/undermining of the common Sports Hernia Protocol: adductor longus-rectus abdominis aponeurosis, and avulsion of the adductor 1. Tearing and detachment of the com- longus from the pubic symphysis (arrow). mon right adductor longus – rectus abdominis (AL-RA) aponeurosis with moderate adductor longus and dis- 3A 3B tal rectus abdominis partial thickness tearing/muscle strains. 2. Moderate fluid and edema surrounding these areas along the anterior superficial soft tissues com- patible with edema and contusion.

Discussion Groin pain in athletes has long been a diagnostic and therapeutic challenge. Injuries to the groin region most commonly result from activities requiring 3C 3D rapid acceleration, deceleration, twist- ing, lateral motion, and abrupt changes in direction. Sports including soccer, American football, hockey, and baseball have been associated with particularly high rates of activity- induced groin pain, or athletic pubalgia. Up to 13% of soccer injuries involve the groin [1, 2]. Initially, sports related groin injuries were labeled ‘sports hernias’ secondary to the anatomic proximity to the superficial 3 Axial T2-weighted TSE FS. Sequential images from superior to inferior (3A-D) inguinal ring. However, the term showing stripping/undermining of the common adductor longus-rectus ‘sports hernia’ is a misnomer as MRI abdominis aponeurosis (denoted by the arrows) and avulsion of the adductor has shown true hernias to be infre- longus from the pubic symphysis (*). quent in this athletic population. The terms athletic pubalgia and core injury (more recently) have been used to and multiple tendon attachments. resisting shear forces. The arcuate describe this entity [6]. The arcuate (anterior inferior) and ligament lines the inferior margin of the superior, anterior, and posterior the pubic symphysis in close associa- The pubic symphysis is an amphiar- pubic ligaments encase the pubic tion with the articular disc and the throdial joint with an articular disc articulation. The arcuate ligament rectus abdominis/adductor longus interposed between 2 pubic bones. and the superior pubic ligament are aponeurosis. The pubic symphysis The joint is stabilized by 4 ligaments the strongest and most crucial for stabilizes the anterior pelvis while

MAGNETOM Flash | 5/2014 | www.siemens.com/magnetom-world 25 Clinical Orthopedic Imaging still allowing a small degree of cra- chanical forces on the opposing mus- aponeurosis and subjacent bone. niocaudal movement at the joint [3, cles and tendons leading to further These injuries are best seen on sagittal 5]. injury at the aponeurosis and its MR imaging and range from small attachments [7]. Continued athletic microtears to complete disruption/ The lower abdominal wall muscles activity in the setting of pelvic insta- detachment of the common attach to the pubic symphysis, bility may result in progressive/addi- aponeurosis. including the rectus abdominis, inter- tional injury to the surrounding nal and external obliques, and the The secondary cleft sign was originally structures. transversus abdominis. The adductor described as an arthrographic finding muscles in the medial thigh also following injection of the symphysis attach to the pubis and include the Imaging features pubis with abnormal inferior extension pectineus, adductor longus, adductor MR imaging: of contrast from the central symphy- brevis, adductor magnus, and graci- Small field-of-view high resolution seal fibrocartilaginous cleft. This was lis. Functionally, the rectus abdomi- MR image acquisition of the pubic felt to represent a microtear of the nis and the adductor longus are the symphysis is obtained in the axial, adductor longus and gracilis tendon most critical for stability at the ante- sagittal, and coronal planes using a origins. An MRI equivalent of the sec- rior pelvis [3, 6]. Along the lateral 3T MAGNETOM Verio system. Sagittal ondary cleft is visible on fluid-sensitive margin of the pubis, the adductor images are most helpful in depicting sequences as a curvilinear fluid-signal longus blends with the inferior rectus the adductor longus-rectus abdomi- interface that is continuous with the abdominis attachment. At the mid- nis aponeurosis. Water-sensitive symphysis pubis and undermines the line, the inferior rectus abdominis, sequences, such as Proton Density inserting structures at the pubis [10]. adductor fibers, arcuate ligament, TSE with fat saturation, are used to Although the exact etiology of the sec- and anterior pubic periosteum form detect abnormal bone marrow signal ondary cleft remains to be elucidated, the aponeurotic plate [6]. During within the pubis associated with this most likely represents a tear of the core rotation and extension, the rec- stress-related changes, avulsion inju- adductor longus origin and AL-RA apo- tus abdominis and the adductor lon- ries, bone contusion, fracture, and neurosis and because of the interre- gus are relative antagonists. While other inflammatory, infectious, or lated anatomy may extend bilaterally the rectus elevates the anterior pel- infiltrative processes. [11]. vis, the adductor longus depresses it. Osteitis pubis is believed to result from Injury of one of the these two com- Strains or small tears of the muscles instability of the pubic symphysis asso- ponents causes abnormal biome- and tendons are most common and demonstrate increased intramuscular ciated with repetitive shear and dis- and intra-tendinous signal on water- traction injuries and an imbalance of 4 sensitive sequences. Isolated tears of the forces applied by the inserting the adductor longus or rectus abdominal wall and adductor muscle abdominis tendons present as high groups. The earliest MR sign of osteitis MR fluid-signal filled defects in the pubis is diffuse subarticular marrow tendons. In the acute phase, sur- edema bordering the symphysis pubis. rounding hemorrhage and edema are The marrow edema is typically gener- present. Myotendinous injuries at the alized and bilateral. Additional find- pubis most commonly involve the ings representative of osteitis pubis adductor muscle group, with the include periostitis, bony resorption, adductor longus being the most com- subchondral cysts and osteophytes [8]. monly injured. Proximal adductor longus tendon tears at the pubis fre- Treatment and prognosis quently extend into the common Treatment strategies for patients with aponeurosis [8]. groin pain are evolving, guided by an In the distal rectus abdominis, the improved understanding of the biome- lateral attachment is most frequently chanics of the anterior pelvis and a injured [9]. Axial images best demon- more focused imaging approach. Con- strate interruption of the distal rectus servative treatment is often successful abdominis tendon just superior to its with isolated tendon or myotendinous attachment to the pubis. Chronic strains. In more severe injuries, steroid injuries of the rectus abdominis mus- injections in the region of the symphy- 4 Sagittal T2-weighted TSE FS. Left common adductor longus-rectus cle or tendon may result in muscle sis pubis or adductor tendon origin abdominis aponeurosis shows atrophy and asymmetry in muscle may be utilized. However, since steroid continuity with overlying soft bulk. injections do not address the underly- tissue swelling, edema, and con- ing injury, symptoms frequently recur tusion from the contralateral Avulsion injuries or tears of the com- with resumption of athletic activities. right common aponeurosis injury. mon AL-RA aponeurosis are seen as Surgery is considered if non-operative, fluid signal interposed between the

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5 Sagittal T2-weighted TSE FS. Right common adductor longus-rectus abdominis aponeurosis avulsion with surrounding muscle strain/hemorrhage (medial to lateral).

conservative treatment fails after 6-8 References 7 Omar IM, et al. Athletic Pubalgia and “Sports Hernia”: Optimal MR Imaging Technique and weeks. Hernia repair without a detect- 1 Ekstrand J, Gillquist J. The avoidability of Findings. RadioGraphics2008; able hernia has reported variable suc- soccer injuries. Int J Sports Med 28:1415-1438. cess rates with either a conventional 1983;4(2):124–8. 8 Stadnick ME. Athletic Pubalgia. MRI Web 2 Ekstrand J, Hilding J. The incidence and or laparoscopic approach, commonly Clinic. February 2010. differential diagnosis of acute groin using mesh to repair and reinforce the 9 Gamble JG, Simmons SC, Freedman M. The injuries in male soccer players. Scand J abdominal wall. Some authors suggest symphysis pubis: anatomic and pathologic Med Sci Sports 1999; 9:98–103. considerations. Clin orthop Relat Res 1983; that success in these patients may 3 Omar IM, Zoga AC, Kavanagh EC, et al. 203: 261-272. result from scarring of the inserting Athletic pubalgia and “sports hernia”: 10 Cunningham PM, et al. Patterns of bone and structures in the pubic region that sec- optimal MR imaging technique and soft-tissue injury at the symphysis pubis in ondarily stabilizes the unrecognized findings. Radiographics 2008; 28: soccer players: observations at MRI. AJR 1415–38. symptomatic anatomic defect [12]. 2007; 188:W291-W296. 4 Walheim GG, Selvik G. Mobility of the Current surgical treatment is focused 11 Zoga AC, et al. Athletic Pubalgia and the pubic symphysis: in vivo measurements on correcting the underlying anatomic “Sports Hernia”: MR Imaging Findings. with an electromechanic method and a Radiology, 2008, 247 (3):797-807. defect and stabilizing the anterior pel- roentgen stereophotogrammetric 12 Meyers WC, et al. Management of severe vis, and these targeted surgical repairs method. Clin Orthop Relat Res 1984; lower abdominal or inguinal pain in high have resulted in improved outcomes 191: 129–35. performance athletes. PAIN (Performing [12, 13]. Pelvic floor repair with reat- 5 Walheim G, Olerud S, Ribbe T. Mobility Athletes with Abdominal or Inguinal Neuro- of the pubic symphysis: measurements tachment of the lateral margin of the muscular Pin Study Group). Am J Sports by an electromechanical method. Acta rectus abdominis tendon at the pubis Med 2000; 28: 2-8. Orthop Scand 1984; 55(2):203–8. has been associated with some of the 13 Taylor DC, et al. Abdominal musculature 6 Khan W, et al. Magnetic Resonance abnormalities as a cause of groin pain in highest success rates. Depending on Imaging of Athletic Pubalgia and the athletes: inguinal hernias and pubalgia. Am associated injuries, adductor tendon Sports Hernia. Current Understanding J Sports Med 1991; 19: 239-242. release or tenotomy may also be per- and Practice. Magn. Reson Imaging Clin 14 Koulouris G. Imaging Review of Groin Pain formed. Isolated full-thickness adduc- N Am 21 (2013) 97-110. in Elite Athletes: An Anatomic Approach to tor tendon avulsions are typically sur- Imaging Findings. AJR 2008; 191:962-972. gically reattached. Osteitis pubis is initially managed by Contact non-steroid anti-inflammatory drugs (NSAID) therapy and physical rehabili- Charles P. Ho, Ph.D., M.D. tation. Steroid injections are consid- Steadman Philippon Research Institute ered as the next line of therapy. Sym- 181 W. Meadow Drive, Suite 1000 Vail, CO 81657 physeal arthrodesis is reserved for USA patients failing conservative measures [email protected] [7].

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