title: Tendon involvement in the feet of patients with gout: a dual-energy CT study.
abstract: OBJECTIVE
  To examine the frequency and patterns of monosodium urate (MSU) crystal deposition in tendons and ligaments in patients with gout using dual-energy CT (DECT).
  
  
  METHODS
  Ninety-two patients with tophaceous gout had DECT scanning of both feet. Two readers scored the DECT scans for MSU crystal deposition at 20 tendon/ligament sites and 42 bone sites (total 1840 tendon/ligament sites and 3864 bone sites).
  
  
  RESULTS
  MSU crystal deposition was observed by both readers in 199/1840 (10.8%) tendon/ligament sites and in 399/3864 (10.3%) bone sites (p=0.60). The Achilles tendon was the most commonly involved tendon/ligament site (39.1% of all Achilles tendons), followed by the peroneal tendons (18.1%). Tibialis anterior and the extensor tendons were involved less commonly (7.6-10.3%), and the other flexor tendons, plantar fascia and deltoid ligaments were rarely involved (<5%) (p<0.0001 between sites). Involvement of the enthesis alone was more common in the Achilles tendon (OR (95% CI) 74.5 (4.4 to 1264), p<0.0001), as was any involvement of the enthesis (OR (95% CI) 6.8 (3.6 to 13.0), p<0.0001).
  
  
  CONCLUSIONS
  Tendons are commonly affected by MSU crystal deposition in patients with tophaceous gout. The patterns of MSU crystal deposition suggest that biomechanical strain or other local factors may contribute to deposition of MSU crystals.
authors: Bone and Joint Research Group, Department of Medicine, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand. n.dalbeth@auckland.ac.nz
authors: Nicola
authors: N
authors: Dalbeth
authors: Ramanamma
authors: R
authors: Kalluru
authors: Opetaia
authors: O
authors: Aati
authors: Anne
authors: A
authors: Horne
authors: Anthony J
authors: AJ
authors: Doyle
authors: Fiona M
authors: FM
authors: McQueen
mesh_terms: D015502:Absorptiometry, Photon; D000125:Achilles Tendon / Q000000981:diagnostic imaging / Q000378:metabolism / Q000473:pathology*; D003460:Crystallization; D005260:Female; D006073:Gout / Q000150:complications / Q000378:metabolism / Q000473:pathology*; D006801:Humans; D008022:Ligaments / Q000000981:diagnostic imaging / Q000378:metabolism / Q000473:pathology; D008297:Male; D008875:Middle Aged; D052256:Tendinopathy / Q000150:complications / Q000378:metabolism / Q000473:pathology*; D014057:Tomography, X-Ray Computed / Q000379:methods*; D014527:Uric Acid / Q000378:metabolism*
chemical_list: D014527:Uric Acid
keywords: Gout; Inflammation; Tendinitis