Related Experiment Video
Updated: Apr 11, 2026

In Vivo Quantification of Hip Arthrokinematics during Dynamic Weight-bearing Activities using Dual Fluoroscopy
Published on: July 2, 2021
Evaluating the Association Between Core Muscle Injury Symptom Pattern and Concomitant Femoroacetabular Impingement
Allison R Garden1,2, Andrea M E Palazzolo Ray1, Adam Alakhras1
1Indiana University School of Medicine, Department of Orthopaedic Surgery, Indianapolis, Indiana, USA.
Background:
Femoroacetabular impingement (FAI) morphology may contribute to abnormal loading of the adductor-rectus abdominis (RA) aponeurosis and development of core muscle injury (CMI) in cutting-pivoting athletes. It is unclear whether CMI with combined RA and adductor longus (RA-AL) symptoms has a higher prevalence of FAI morphology than CMI with AL symptoms alone.
Purpose/Hypothesis:
The purpose was to determine (1) whether athletes with CMI with RA-AL or isolated AL symptoms differ in prevalence of FAI syndrome (FAIS) and (2) whether prevalence or severity of FAI morphology differs between these groups. It was hypothesized that athletes with RA-AL symptoms will have a higher prevalence of FAIS and more severe FAI morphology than those with AL symptoms alone.
Study Design:
Case series; Level of evidence, 4.
Methods:
Athletes who underwent surgical treatment of a CMI between 2021 and 2025 at a single center were identified. Patients were categorized as RA-AL or AL based on symptoms and physical examination findings. FAIS status was determined by symptomatic impingement morphology and treated with hip arthroscopy and core muscle surgery. Impingement anatomy was assessed on radiographs via lateral center-edge angle, crossover ratio, ischial spine sign, head-neck offset ratio, anterior center-edge angle, and α angle.
Results:
A total of 65 athletes with CMI were included (median age 21 years; IQR 18-43; 97% male); 42 (65%) had RA-AL and 23 (35%) had AL symptoms. No baseline demographic differences were identified between groups. The prevalence of symptomatic FAIS was 38% (25/65) overall and was lower (29%; 12/42) in the RA-AL group than the AL group (57%; 13/23) (P = .03). Almost all athletes with CMIs (98%; 64/65) demonstrated FAI morphology, irrespective of symptoms; 95% (62/65) had cam-type, 40% (26/65) had pincer-type, and 38% (24/65) had mixed impingement morphology. No differences in radiographic measurements or impingement type were found between groups (P > .05).
Conclusion:
There is a very high prevalence of FAI morphology, particularly femoral cam morphology, in both RA-AL and AL symptomatic athletes with CMI, suggesting a likely role of FAI morphology in CMI development. Symptomatic FAI is more common in athletes with isolated AL symptoms versus RA-AL symptoms. Type and degree of radiographic FAI morphology were not associated with specific CMI symptom patterns.
More Related Videos
08:19Author Spotlight: Unraveling the Mechanobiology of Tendon Impingement – A Multiaxial Murine Hind Limb Explant Model
Published on: December 8, 2023
09:51The Transition to an Anterior-Based Muscle Sparing Approach Improves Early Postoperative Function but is Associated with a Learning Curve
Published on: September 7, 2022
Related Concept Videos
Bones of the Lower Limb: Femur and Patella
Appendicitis-I: Introduction
Etiology: Appendicitis can arise from various causes, primarily rooted in the obstruction of the appendix lumen. Factors contributing to this obstruction include fecal accumulation, lymphoid hyperplasia and, in...
Assessment of the Abdomen II: Percussion
Percussion
Percussion is an essential...
Muscles that Move the Thigh
Three other significant muscles are the gluteus maximus, gluteus medius, and gluteus minimus. The gluteus maximus originates from the posterior surface of the ilium, sacrum, and coccyx, and the thoracolumbar...
Muscles of the Pelvic Floor and Perineum
Perineal Layer
The perineum is a diamond-shaped area below the pelvic diaphragm, divided into an anterior urogenital triangle that contains the external genitals and a posterior anal triangle housing the anus. The urogenital...
Functional Classification of Joints
The functional classification of joints is determined by the amount of mobility between the adjacent bones. Joints are functionally classified as a synarthrosis or immobile joint, an amphiarthrosis or slightly moveable joint, or as a diarthrosis, a freely moveable joint. Fibrous and cartilaginous joints can be functionally classified as either synarthroses or amphiarthroses, whereas all synovial joints are classified as diarthroses.
Synarthrosis
An...