Differential Diagnosis for Superior and Posterosuperior Partial-Thickness Acetabular Labrochondral Junction Separation

• Single most likely diagnosis
  • Femoroacetabular impingement (FAI): This condition is the most likely diagnosis due to the location and nature of the injury. FAI can cause labral tears and cartilage damage, especially in the superior and posterosuperior regions of the acetabulum, due to abnormal contact between the femoral head and the acetabulum.
• Other Likely diagnoses
  • Labral tear: A tear in the labrum, which is the cartilage that surrounds the socket of the hip joint, can cause symptoms similar to those of a labrochondral junction separation. The location of the tear can vary but often corresponds to areas of high stress, such as the superior and posterosuperior regions.
  • Chondral injury: An injury to the cartilage of the acetabulum or the femoral head can occur in conjunction with or independently of a labral tear, leading to pain and dysfunction in the hip.
  • Hip subluxation or dislocation: Traumatic events can cause the hip to partially or completely dislocate, leading to injuries at the labrochondral junction among other potential damage.
• Do Not Miss diagnoses
  • Osteonecrosis: Although less likely, osteonecrosis (avascular necrosis) of the femoral head can present with hip pain and must be considered to avoid missing a potentially devastating condition that requires prompt treatment.
  • Infection (septic arthritis): Infection within the hip joint is a medical emergency that requires immediate attention. While less common, it can present with pain and must be ruled out, especially in the presence of systemic symptoms like fever.
• Rare diagnoses
  • Synovial chondromatosis: A rare condition characterized by the growth of cartilage in the synovium of the joint, which can cause mechanical symptoms and joint damage.
  • Pigmented villonodular synovitis (PVNS): A rare disease that causes the synovium to thicken and overgrow, leading to joint damage and pain.