Differential Diagnosis for Hip Pain and Tendinopathy

• Single most likely diagnosis:
  • Greater Trochanteric Pain Syndrome (GTPS): This condition is characterized by pain over the greater trochanter due to tendinopathy of the gluteus medius and/or minimus, and sometimes bursitis. The presence of a full-thickness tear of the gluteus minimus tendon, severe tendinosis of the gluteus medius, and mild bursitis in the region makes GTPS the most likely diagnosis.
• Other Likely diagnoses:
  • Iliotibial (IT) Band Syndrome: Given the ITB tendinopathic changes, IT Band Syndrome is a plausible diagnosis, especially if the patient presents with lateral thigh pain and snapping or clicking sensations.
  • Hip Osteoarthritis: Although not directly mentioned, the presence of a hip joint effusion could suggest an underlying degenerative condition such as osteoarthritis, which might contribute to the patient's symptoms.
• Do Not Miss (ddxs that may not be likely, but would be deadly if missed.):
  • Septic Arthritis or Osteomyelitis: Infection within the hip joint or bone could present with similar symptoms, including pain and effusion. Although less likely, missing these diagnoses could have severe consequences, including joint destruction or systemic infection.
  • Avulsion Fracture: A fracture at the site of tendon attachment could mimic the symptoms of tendinopathy and should be considered, especially if there's a history of trauma.
• Rare diagnoses:
  • Gluteus Medius or Minimus Rupture due to Trauma: While the full-thickness tear of the gluteus minimus is noted, considering the context of severe tendinosis without a tear in the gluteus medius, a traumatic rupture, although less common, should be kept in mind, especially with appropriate history.
  • Tumor or Cystic Lesions: Rarely, soft tissue tumors or cysts could cause similar symptoms by compressing or infiltrating the tendons and bursae around the hip.