title: Prevalence of knee abnormalities in patients with osteoarthritis and anterior cruciate ligament injury identified with peripheral magnetic resonance imaging: a pilot study.
abstract: OBJECTIVE
  1) To assess, with a peripheral magnetic resonance imaging system (pMRI), the prevalence of bony and soft tissue abnormalities in the knee joints of normal subjects, osteoarthritis (OA) patients, and individuals who have suffered an anterior cruciate ligament (ACL) rupture; and 2) to compare the prevalence among groups.
  
  
  METHODS
  Magnetic resonance (MR) images of 28 healthy, 32 OA, and 26 ACL damaged knees were acquired with a 1.0-T pMRI system. Two radiologists graded the presence and severity of 9 MR image features: cartilage degeneration, osteophytes, subchondral cyst, bone marrow edema, meniscal abnormality, ligament integrity, loose bodies, popliteal cysts, and joint effusion.
  
  
  RESULTS
  Ten of 28 healthy (35.7%), 24 of 26 ACL (92.3%), and all OA knees (100%) showed prevalent cartilage defects; 5 healthy (17.9%), 20 ACL (76.9%), and all OA knees (100%) had osteophytes; and 9 normal (32.1%), 21 ACL (80.8%), and 29 OA knees (90.6%) had meniscal abnormalities. One-half of the knees in the OA group (16 of 32, 50%) had subchondral cysts, and almost one-half had bone marrow edema (15 of 32, 46.9%). These features were not common in the ACL group (7.7%, and 11.5%, respectively) and were not observed in healthy knees. The OA group had the most severe cartilage defects, osteophytes, bone marrow edema, subchondral cysts, and meniscal abnormalities; the ACL group showed more severe cartilage defects, osteophytes, and meniscal abnormalities than did normal subjects.
  
  
  CONCLUSIONS
  The results suggest that knees that have sustained ACL damage have OA-like reatures; most subjects (19 of 26, 73.1%) could be identified as in the early stage of OA. The prominent abnormalities present in ACL-damaged knees are cartilage defects, osteophytes, and meniscal abnormalities.
authors: Department of Medical Sciences, McMaster University, Hamilton, ON. wuh5@mcmaster.ca
authors: Hao
authors: H
authors: Wu
authors: Colin
authors: C
authors: Webber
authors: Carmen Otero
authors: CO
authors: Fuentes
authors: Robert
authors: R
authors: Bensen
authors: Karen
authors: K
authors: Beattie
authors: Jonathan D
authors: JD
authors: Adachi
authors: Xiaoming
authors: X
authors: Xie
authors: Farhang
authors: F
authors: Jabbari
authors: David R
authors: DR
authors: Levy
mesh_terms: D000328:Adult; D000070598:Anterior Cruciate Ligament Injuries; D002358:Cartilage, Articular / Q000473:pathology; D005260:Female; D006801:Humans; D007719:Knee Joint / Q000473:pathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008592:Menisci, Tibial / Q000473:pathology; D010003:Osteoarthritis / Q000473:pathology*; D020370:Osteoarthritis, Knee / Q000473:pathology; D010865:Pilot Projects; D015995:Prevalence