title: Glycosaminoglycan measured from synovial fluid serves as a useful indicator for progression of Osteoarthritis and complements Kellgren-Lawrence Score.
abstract: BACKGROUND
  Plain radiography is the first choice for diagnosis and monitoring of knee-osteoarthritis (OA) while, Kellgren-Lawrence score (KL) is most widely used to grade OA severity. However, incompetency for reproducibility of joint space measurement in longitudinal assessment and non-linearity of KL-score system, limits radiography-based early diagnosis of the disease. Glycosaminoglycan (GAG) is direct cartilage-degradation product, which can be measured biochemically. We strived to correlate KL-score and GAG from OA patients to compliment KL-system.
  
  
  METHODS
  We obtained 34 synovial-fluid (SF) samples from 28 OA patients (few bilateral) with different disease severity using arthrocetesis. All patients were categorised using radiographic KL-score-system. SFs were further analysed for GAG estimation using 1,2-dimethylmethylene blue (DMMB) assay.
  
  
  RESULTS
  A substantial increase in GAG was noted in KL-grade-II and III, comparing grade-I patients, indicating amplified cartilage-degradation. KL-grade-IV patients revealed further rise in GAG reflecting more cartilage-loss. Another category of grade-IV patients with lower GAG were also detected, indicating close to total cartilage-loss.
  
  
  CONCLUSIONS
  Accurate diagnosis of cartilage-loss remains a challenge with OA due to limitations of KL-system; thus no target intervention is available to arrest active cartilage-loss. We propose, GAG-estimation in OA patients, characterizes accurate biochemical depiction of cartilage degeneration.
  
  
  CONCLUSIONS
  Radiology often fails to reveal an accurate cartilage loss, associated with OA. GAG levels from the SFs of OA patients' serve as a useful marker, which parallels cartilage degeneration and strengthen radiographic grading system, ultimately.
authors.affiliation: Interactive Research School for Health Affairs (IRSHA), Bharati Vidyapeeth University, Pune-Satara Road, Pune 411043, India.
authors.forename: Priya
authors.initials: P
authors.lastname: Kulkarni
authors.affiliation: Department of Orthopaedics, Bharati Hospital, Pune-Satara Road, Pune 411043, India.
authors.forename: Shantanu
authors.initials: S
authors.lastname: Deshpande
authors.affiliation: Interactive Research School for Health Affairs (IRSHA), Bharati Vidyapeeth University, Pune-Satara Road, Pune 411043, India.
authors.forename: Soumya
authors.initials: S
authors.lastname: Koppikar
authors.affiliation: Department of Orthopaedics, Bharati Hospital, Pune-Satara Road, Pune 411043, India.
authors.forename: Sanjay
authors.initials: S
authors.lastname: Patil
authors.affiliation: Interactive Research School for Health Affairs (IRSHA), Bharati Vidyapeeth University, Pune-Satara Road, Pune 411043, India.
authors.forename: Dhanashri
authors.initials: D
authors.lastname: Ingale
authors.affiliation: Interactive Research School for Health Affairs (IRSHA), Bharati Vidyapeeth University, Pune-Satara Road, Pune 411043, India.
authors.forename: Abhay
authors.initials: A
authors.lastname: Harsulkar
keywords: Glycosaminoglycan; Joint-space-narrowing; Kellgren–Lawrence score; Knee-osteoarthritis; Radiography; Synovial-fluid