Radiology, Vol 198, 845-849, Copyright © 1996 by Radiological Society of North America
Enlargement of the third intercondylar tubercle of Parsons as a sign of osteoarthritis of the knee: a paleopathologic and radiographic study
J Brossmann, LM White, A Stabler, KW Preidler, R Andresen, P Haghighi and D Resnick
Department of Radiology, Veterans Administration Medical Center, San Diego, California 92161, USA.
PURPOSE: To correlate presence and size of the third intercondylar tubercle
of Parsons (TITP) with occurrence and severity of osteoarthritis of the
knee. MATERIALS AND METHODS: In 100 paleopathologic tibial specimens and on
160 clinical knee radiographs, size of the TITP was correlated with
osteoarthritis of medical and lateral femorotibial joints (FTJ) and with
prominence of tibial spines. RESULTS: TITP size correlated significantly
with osteoarthritis of the tibial plateau in the paleopathologic specimens
(P<.0001). TITP size correlated significantly with osteoarthritis of
medial FTJ and tibial spines on radiographs (P<.0001). Of 85 patients
without osteoarthritis of the medial FTJ, 49 (58%) had no TITP, 33 (39%)
had small TITPs, and three (4%) had medium or large TITPs. TITPs were found
in 15 (88%) of 17 patients with pronounced osteoarthritis. CONCLUSION:
Frequency and prominence of TITPs are increased in patients with
osteoarthritis of the medial FTJ and prominent tibial spines. Prominent
TITP is a secondary sign of osteoarthritis. At histologic examination,
increasing size of TITPs represents osteophytosis or enthesopathy of the
TITP.
