S39.011A – Strain of muscle, fascia and tendon of abdomen, initial encounter
285348005 – Strain of abdominal muscle
Differential Diagnosis & Pitfalls
- Femoroacetabular impingement syndrome (FAI) – Flexion, adduction, and internal rotation test may reproduce symptoms. Plain radiographs may show cam, pincer, or mixed morphology for diagnosis.
- Acetabular labral tear – MRI may show tear.
- Osteochondral lesion – Plain radiographs may show lesion.
- Femoral neck stress fracture – Plain radiographs may show fracture.
- Osteoarthritis – Often seen in older adults. Radiographs can show characteristic joint space changes.
- Transitory synovitis – Most often seen in patients aged 3-8 years. Often bilateral.
- Osteonecrosis of the femoral head – Seen on MRI without contrast.
- Osteochondritis dissecans – Plain radiographs often show characteristic bony lesion.
- Epiphysiolysis of the femoral head – Most often seen in adolescents. Plain radiographs may show characteristic findings.
- Septic arthritis – Joint aspiration will show evidence of infection.
- Tumor – Multiple imaging modalities may show tumor.
- Tendon strain or tendinopathy of hip flexor or adductor origin or rectus abdominis insertion – Physical examination may show focal pain.
- Adductor muscle strain – Physical examination may show focal pain. MRI may help to confirm.
- Osteitis pubis – Pubic symphysis tenderness may be present.
- Pubic ramus stress fracture – Focal tenderness. Plain radiographs and MRI show bony changes.
- Apophyseal avulsion fracture
- Snapping hip syndrome – Characteristic "snap" heard by patient or observer.
- Sacroiliac joint disorder – Tests of pelvic symmetry may be helpful.
- Lumbar radiculopathy – Characteristic clinical diagnosis.
- Nerve entrapment (ilioinguinal, obturator)
- Adnexal torsion – Ultrasound may be helpful.
- Ovarian cyst – Ultrasound may be helpful.
- Pelvic inflammatory disease – Patient is sexually active. Characteristic findings on pelvic examination.
- Urinary tract infection – Evidenced by history and urinalysis.
- Endometriosis – Seen on ultrasound.
- Nephrolithiasis – Evidenced by history and abdominal CT to visualize ureters / kidneys.
- Prostatitis (acute, chronic) – Digital rectal examination shows tender, edematous prostate.
- Epididymitis – Localized testicular pain with tenderness and swelling of epididymis.
- Orchitis – Localized testicular pain.
- Testicular torsion – Acute onset, negative cremasteric reflex, severe testicular pain.
- Testicular cancer – Evidenced by scrotal ultrasound.
- Intra-abdominal pathologies
- Inguinal hernia – Physical examination shows bulge in groin, confirmed by ultrasound.
- Appendicitis – McBurney's point tenderness, CT / ultrasound of abdomen, CBC.
- Diverticulitis / diverticulosis – Seen on CT with contrast.
- Inflammatory bowel disease (see Crohn disease, ulcerative colitis) – Evidenced by history, including gastrointestinal (GI) symptoms.