Core muscle injuries

Anatomical pathophysiology

• Core muscle weakness (usually from fraying associated with hyperextension or hyperabduction) results in an imbalance of forces on the pelvis
• This imbalance causes disruption of the attachments to firbocartilaginous plate of the pubic bone, causing pain, weakness and instability
• Loss of stability leads to compensation from the other structures that cross the pubic bone (iliopsoas, rectus femoris, sartorius) which can then become additional sources of pain and injury
• Anatomic variants predisposing to certain injuries:
  • Symptomatic femoroacetabular impingement results in spasms of the adductors (primarily adductor longus) and hip flexors (primarily rectus femoris)

Differential diagnosis of groin pain in athletes

• Hip
  • Acetabular labral tear and femoroacetabular impingement
  • OA
  • Snapping hip syndrome and iliopsoas tendonitis
  • Avascular necrosis
  • Iliotibial band syndrome
• Visceral
  • Inguinal hernia
  • Other abdo hernias
  • Testicular torsion
• Infectious
  • Septic arthritis
  • Osteomyelitis
  • PID
  • Prostatitis
  • Epididymitis and orchitis
  • Herpes
• Inflammatory
  • Endometriosis
  • IBD
  • PID
  • Primary osteitis pubis
• Traumatic
  • Stress fracture
  • Tendon avulsion
  • Muscle contusion
  • Baseball pitcher-hockey goalie syndrome
• Developmental
  • Apophysitis
  • Growth plate stress injury or fracture
  • Legg-Calve-Perthes syndrome
  • Developmental dysplasia
  • Slipped capital femoral epiphysis
• Neurologic
  • Nerve entrapment syndromes
  • Referred pain
  • Sacroileitis
  • Sciatis entrapment (piriformis syndrome)
  • Hamstring strain
  • Knee pain
• Neoplastic
  • Testicular cancer
  • Osteoid osteoma

Diagnostic approach

• Basic history aligned to above categories
• Classically, these injuries improve with rest, but pain returns upon resuming activities
• FABER/FADIR test
• Localised tenderness
• Imaging
  • Plain films
  • MRI - 'athletic pubalgia protocol'

Management

• Principles
  • Injuries involving central pubic bone attachments generally leave an athlete with instability that cannot be corrected until normal anatomy is restored
• Non-operative
  • PT to strengthen lateral and posterior core muscles to offload the injury and stabilise the pubic joint
  • Corticosteroid injections to the affected area can temporise the issue in about 80% of patients, and do not seem to result in subsequent worse operative outcomes