Glycosaminoglycan measured from synovial fluid serves as a useful indicator for progression of Osteoarthritis and complements Kellgren–Lawrence Score

摘要

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. General Significance: 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