Differential Diagnosis for Pelvic Radiograph Findings
Single Most Likely Diagnosis
- Osteoarthritis (OA): The presence of moderate to marked hip joint narrowing, advanced arthritic changes, subchondral sclerosis, and juxta-articular cysts around the left hip joint, along with similar but less severe changes on the right, strongly suggests OA as the primary diagnosis. The bilateral cam-type morphology further supports this, as it is a known risk factor for the development of hip OA.
Other Likely Diagnoses
- Femoroacetabular Impingement (FAI): The suspected cam-type morphology bilaterally is a hallmark of FAI, which can lead to or exacerbate OA. The presence of arthritic changes and hip joint narrowing supports the consideration of FAI as a contributing factor.
- Enthesopathy: Minor enthesopathic changes throughout the pelvic bones' attachments, including over the greater trochanters bilaterally, suggest an enthesopathic process, possibly related to a seronegative spondyloarthropathy or another condition affecting tendon and ligament insertions.
Do Not Miss Diagnoses
- Infection or Septic Arthritis: Although less likely given the chronic appearance of the changes, infection or septic arthritis could present with joint narrowing and sclerosis. It is crucial to consider this diagnosis due to its potential for severe consequences if missed.
- Malignancy: The presence of juxta-articular cysts and sclerosis could, in rare cases, be associated with a malignant process. While unlikely, the potential severity of missing a diagnosis of malignancy warrants its inclusion in the differential.
Rare Diagnoses
- Rheumatoid Arthritis (RA): Although RA can cause hip joint narrowing and arthritic changes, the pattern described, with a focus on subchondral sclerosis and cam-type morphology, is less typical for RA. However, it remains a consideration, especially if systemic symptoms are present.
- Seronegative Spondyloarthropathies (e.g., Ankylosing Spondylitis, Psoriatic Arthritis): These conditions can cause enthesopathy, hip joint involvement, and sclerosis. The relatively normal appearance of the SI joints makes this less likely, but it should be considered, especially if there are systemic symptoms or a suggestive clinical history.