Poor Accuracy of Clinical Diagnosis in Pes Anserine Tendinitis Bursitis Syndrome.

Objectives: To investigate the characteristics of the patients who are clinically diagnosed with pes anserine tendinitis bursitis syndrome (PATBS), and to determine the sensitivity and specificity of clinical diagnose based on magnetic resonance imaging (MRI).

Methods: Included in this cross-sectional clinical study were 156 patients who were evaluated based on the clinical presence or absence of PATBS. All patients underwent Q-angle measurement, knee osteoarthritis (OA) grading according to the Kellgren-Lawrence classification, and medial joint space measurement, and their cartilage thickness, and any periarticular and intraarticular knee pathologies were recorded from an assessment of knee MRIs.

Results: Of the total, 64 cases (41%) were diagnosed clinically with PATBS and 92 (59%) were not. There was no difference in the Q angles of the two groups ( p  > 0.05), while the medial joint spaces were significantly lower in the PATBS patients ( p  < 0.05). There were no significant differences between the two groups in an MRI assessment of meniscus and ligament lesions, chondromalacia patella, cyst, bursitis, effusion and synovial pathologies ( p  > 0.05). The sensitivity and specificity of the PATBS clinical diagnoses relative to the MRI findings were determined as 41.2% and 59.5%, respectively.

Conclusion: The medial joint space was found to be significantly lower in patients with PATBS, while there was no difference in any other knee pathologies between the two groups. The sensitivity and specificity of a PATBS clinical diagnosis were found to be low, and so it was concluded that clinical PATBS diagnoses may be inaccurate, particularly in the presence of such invasive therapies as injection, and that diagnoses based on imaging methods would be more accurate.