title: Identification of infrared absorption spectral characteristics of synovial fluid of horses with osteochondrosis of the tarsocrural joint.
abstract: OBJECTIVE
  To determine the feasibility of the use of Fourier-transform infrared (FTIR) spectroscopy within the midinfrared range to differentiate synovial fluid samples of joints with osteochondrosis from those of control samples.
  
  
  METHODS
  33 horses with osteochondrosis of the tarsocrural joint and 31 horses free of tarsocrural joint disease.
  
  
  METHODS
  FTIR spectroscopy of synovial fluid was used. Sixty-four synovial fluid samples from the tarsocrural joint were collected. Of these, 33 samples were from horses with radiographic evidence of osteochondrosis of the tarsocrural joint and 31 from control joints. Disease-associated features within infrared spectra of synovial fluid were statistically selected for spectral classification, and the variables identified were used in a classification model. Linear discriminant analysis and leave-one-out cross-validation were used to develop a classifier to identify joints with osteochondrosis.
  
  
  RESULTS
  12 significant subregions were identified that met the selection criteria. The stepwise discriminant procedure resulted in the final selection of 6 optimal regions that most contributed to the discriminatory power of the classification algorithm. Infrared spectra derived from synovial fluid of joints with osteochondrosis were differentiated from the control samples with accuracy of 77% (81% specificity and 73% sensitivity).
  
  
  CONCLUSIONS
  The disease-associated characteristics of infrared spectra of synovial fluid from joints with osteochondrosis may be exploited via appropriate feature selection and classification algorithms to differentiate joints with osteochondrosis from those of control joints. Further study with larger sample size including age-, breed-, and sex-matched control horses would further validate the clinical value of infrared spectroscopy for the diagnosis of osteochondrosis in horses.
authors.affiliation: Department of Health Management, Atlantic Veterinary College, University of Prince Edward Island, PE, Canada.
authors.forename: Monchanok
authors.initials: M
authors.lastname: Vijarnsorn
authors.forename: Christopher B
authors.initials: CB
authors.lastname: Riley
authors.forename: Daniel A J
authors.initials: DA
authors.lastname: Ryan
authors.forename: Patricia L
authors.initials: PL
authors.lastname: Rose
authors.forename: R Anthony
authors.initials: RA
authors.lastname: Shaw
mesh_terms: D000818:Animals; D005260:Female; D006734:Horse Diseases / Q000175:diagnosis*; D006736:Horses; D007592:Joint Diseases / Q000175:diagnosis / Q000662:veterinary*; D008297:Male; D010007:Osteochondritis / Q000175:diagnosis / Q000662:veterinary*; D013582:Synovial Fluid / Q000737:chemistry*