title: Enlargement of the third intercondylar tubercle of Parsons as a sign of osteoarthritis of the knee: a paleopathologic and radiographic study.
abstract: OBJECTIVE
  To correlate presence and size of the third intercondylar tubercle of Parsons (TITP) with occurrence and severity of osteoarthritis of the knee.
  
  
  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.
  
  
  CONCLUSIONS
  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.
authors.affiliation: Department of Radiology, Veterans Administration Medical Center, San Diego, California 92161, USA.
authors.forename: J
authors.initials: J
authors.lastname: Brossmann
authors.forename: L M
authors.initials: LM
authors.lastname: White
authors.forename: A
authors.initials: A
authors.lastname: Stäbler
authors.forename: K W
authors.initials: KW
authors.lastname: Preidler
authors.forename: R
authors.initials: R
authors.lastname: Andresen
authors.forename: P
authors.initials: P
authors.lastname: Haghighi
authors.forename: D
authors.initials: D
authors.lastname: Resnick
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D005260:Female; D049673:History, 20th Century; D006801:Humans; D007719:Knee Joint / Q000000981:diagnostic imaging* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D010003:Osteoarthritis / Q000000981:diagnostic imaging* / Q000266:history / Q000473:pathology; D010164:Paleopathology; D011859:Radiography; D013977:Tibia / Q000000981:diagnostic imaging* / Q000473:pathology