Abstract | May 5, 2023
MRI Findings in Core Muscle Injury: A Systematic Review
Learning Objectives
- treat core muscle injury with increased accuracy based on MRI findings.
- assess return to play more accurately for athletes with a core muscle injury.
Abstract
Background: Core muscle injury (CMI) describes pathology affecting the musculoskeletal anatomy of the lower abdomen, pelvis, and proximal adductors without evidence of a true hernia. Magnetic resonance imaging (MRI) is required for diagnosis but limited by inconsistent pathologic findings and incongruent nomenclature. The purpose of this study is to summarize the literature regarding MRI evidence of CMI to allow for more accurate diagnosis and treatment. Methods: A systematic literature search of PUBMED, EMBASE, Cochrane CENTRAL, and Web of Science Core Collection was performed from the inception of the databases to April 2022 to identify studies focused on MRI findings in patients with suspected CMI. Studies examining pathological incidence, clinical correlation, and return to play were included. Studies focusing on treatment or other imaging modalities were excluded.
Results: A total of 1912 studies were identified, 23 of which met inclusion criteria. Of the included studies, 15 assessed the pubic symphysis, 17 assessed adductors, 12 assessed the abdominal wall, and 6 assessed hip flexors. There was no consistent definition of pathologic CMI among the included studies. The three most common MRI findings in CMI assessment were bone marrow edema at the pubic symphysis, adductor longus lesions, and rectus abdominis lesions. Evidence of CMI injury on MRI ranging from 4.7% – 23% was seen in asymptomatic patients across multiple studies. Evidence of adductor enthesopathy on MRI showed a significant increase in duration of symptoms (23.5 weeks) and increased groin pain recurrence compared to patients without adductor enthesopathy (6 weeks).
Conclusion: There is no consistent definition of pathologic CMI when evaluated with MRI, as evidenced by the various definitions, muscular groups, sequences, and grading. MRI is a useful tool in determining the presence or extent of CMI, but findings should be considered alongside the clinical presentation of the patient. Aside from diagnosis, MRI is useful in assessing the extent of injury, which can give a more accurate timeframe for athletes returning to their previous level of activity. Understanding the variable MRI findings associated with CMI allows expedited and specific diagnosis of this increasingly recognized pathology, assisting with accurate estimated times for return to play.
