Abstract. Introduction. The effectiveness of single intra-articular injections of polyacrylamide hydrogel (iPAAG) and hyaluronic acid (HA) was compared in subgroups of participants from an RCT based on baseline age, BMI or Kellgren-Lawrence (KL) grade. Methodology. 239 participants were randomised to 6 mL iPAAG (Arthrosamid; n=119) or 6 mL HA (Synvisc-One; n=120). Participants continued analgesics (except 48 hours prior to visits) and non-pharmacological therapy. Topical therapies and intra-articular corticosteroids were not allowed. Pre-specified subgroup analyses (age: <70 years, ≥70 years; BMI: normal, overweight, obese; KL grade: 2, 3, 4, 2–3) of change from baseline in WOMAC pain subscale at 52 weeks were based on the least squares means for the treatment-by-week interaction effect using a mixed model for repeated measurement with a restricted maximum likelihood-based approach. Results. Across all patients, change from baseline in WOMAC pain subscale in the iPAAG group was non-inferior to HA at 26 weeks and approached superiority (p=0.0572) at 52 weeks. Treatment differences for change from baseline in WOMAC pain subscale in favour of iPAAG over HA were statistically significant for the age <70 years (p=0.019), BMI normal (p=0.011) and KL grade 2–3 (p=0.033) subgroups. Treatment differences for all other subgroups favoured iPAAG, except for KL grade 4 which favoured HA, without reaching statistical significance. Conclusion. iPAAG approached superiority to HA across all participants at 52weeks, but demonstrated statistical superiority in participants with normal BMI, participants <70 years old or participants with KL score 2–3. iPAAG represents a useful alternative to HA for the treatment of knee OA

The aim of this study was to compare the efficacy of a hyaluronic acid (HA) supplement and a local anaesthetic (Bupivacaine) at providing early and short-term post-operative anagesic control following knee arthroscopy. Patients were randomised to receive either 10mls of 0.5% Bupivacaine or 10mls of HA into the joint immediately after completion of surgery. WOMAC and Tegner-Lysholm scores were obtained at baseline then at 1, 2, and 6-weeks post surgery. VAS pain scores were obtained at baseline; 1 and 24-hours; and 1, 2 and 6 weeks following surgery. 49 patients received intra-articular Bupivacaine and 49 HA. There was no statistical difference in any of the outcome measures (WOMAC, Tegner-Lysholm, VAS pain scores) at any time point between the groups overall. Patients with grade III-IV chondral defects that received HA reported significantly lower VAS pain scores at rest and movement at all time points. Use of Bupivacaine and HA intra-articular injection results in equivalent analgesic control in the immediate post-operative period and first six-weeks following surgery when administered immediately at the end of knee arthroscopy. Utilizing HA following knee arthroscopy does not sacrifice analgesic control and minimises exposure to chondrotoxic agents. Selective use of HA may improve pain-control in those with advanced chondral defects

Aims

Knee osteoarthritis (OA) is characterized by a chronic inflammatory process involving multiple cytokine pathways, leading to articular cartilage degeneration. Intra-articular therapies using pharmaceutical or autologous anti-inflammatory factors offer potential non-surgical treatment options. Autologous protein solution (APS) is one such product that uses the patient’s blood to produce a concentrate of cells and anti-inflammatory cytokines. This study evaluated the effect of a specific APS intra-articular injection (nSTRIDE) on patient-reported outcome measures compared to saline in moderate knee OA.