To evaluate the benefits of knee joint aspiration and injection in knee osteoarthritis (OA).
A retrospective, pilot study involved 110 patients with knee OA from a dedicated OA clinic in a Melbourne tertiary hospital from 2007 to 2009. Only those who had completed two Multiple Attribute Prioritization Tool (MAPT) questionnaires within 6 months of the initial review were included. The MAPT was designed to help prioritise patients on orthopedic waiting lists. Three groups were analyzed: patients who had no corticosteroid injection or aspiration, patients who received corticosteroid injections, and patients who received both joint aspiration with corticosteroid injections.
Patients who had both joint aspiration and injection reported an improvement in pain compared with those who had no injection (56.3%vs. 32.2%, P = 0.03). Those who had joint injections also did better than those without injection (62.7%vs. 32.2%, P = 0.001). Reduced analgesia use was noted in 12.5% of patients with aspiration and injection compared with 1.7% with no injection or aspiration (P = 0.03). Improved walking distance was noted in 22.4% of patients who had injections compared with 8.5% of patients with no injections (P = 0.03). No significant differences in MAPT scores among the different treatment groups were noted.
This pilot study appears to show a beneficial trend in giving corticosteroid injections and to aspirate the knee in OA patients. Further studies are needed to address the mechanical benefits, quadriceps strengthening and pain reduction with knee aspiration, as well as the effects that different volumes of fluid may have on knee mechanics and symptoms.