Osteoarthritis of the knee: three small RCTs found that intra-articular corticosteroid injections were consistently more effective than placebo for a range of pain and function outcome measures.

Osteoarthritis of the hip: two small RCTs had mixed results that do not provide good evidence to support intra-articular corticosteroid injections of the hip.

Osteoarthritis of the thumb: one small RCT found no significant benefit for intra-articular corticosteroid injections.

Expert opinion is that there is a very small risk of serious adverse effects such as infection.

The National Institute for Health and Clinical Excellence (NICE) reviewed studies on the efficacy and safety of intra-articular injection of corticosteroids in adults with osteoarthritis and found one meta-analysis and three further RCTs [National Collaborating Centre for Chronic Conditions, 2008].

• Knee osteoarthritis: intra-articular corticosteroids compared with placebo:
• A meta-analysis of data from three RCTs with 156 participants found that intra-articular corticosteroid injections were more effective than placebo in terms of:
• Average number of knees improved at 2 weeks post injection (one RCT, n = 71): RR 1.81 (95% CI 1.09 to 3.00, p = 0.02).
• At least 30% decrease in baseline pain at 1 week post injection (one RCT, n = 53): RR 2.56 (95% CI 1.26 to 5.18, p = 0.009).
• At least 15% decrease in baseline pain at 3 weeks post injection (one RCT, n = 118): RR 3.11 (95% CI 1.61 to 6.01, p = 0.0006).
• Change in pain at 1 week post injection (three RCTs, n = 161): WMD –21.91 (95% CI –29.93 to –13.89, p = 0.00001).
• Change in pain at 12 weeks post injection (one RCT, n = 53): WMD –14.20 (95% CI –27.44 to –0.96, p = 0.04).
• Change in pain at 1 year post injection (one RCT, n = 66): WMD –13.80 (95% CI –26.79 to –0.81, p = 0.04).
• Number of people preferring intra-articular corticosteroids (three RCTs, n = 190): RR 2.22 (95% CI 1.57 to 3.15, p < 0.00001).
• Overall improvement (three RCTs, n = 156): RR 1.44 (95% CI 1.13 to 1.82, p = 0.003).
• Hip osteoarthritis: intra-articular corticosteroids compared with placebo:
• An RCT (n = 101 in three arms) found that compared with saline injections, intra-articular corticosteroid injections were:
• More effective in terms of pain on walking: effect size (ES) 0.6 (95% CI 0.1 to 1.1, p = 0.021).
• No significant difference in terms of patient's global assessment and OARSI (Osteoarthritis Research Society International) measures at 2, 4, and 12 weeks after injection.
• An RCT (n = 30) found no significant difference between intra-articular corticosteroid injections and placebo in terms of pain relief at 1, 3, and 12 months after injection.
• Thumb osteoarthritis: intra-articular corticosteroids compared with placebo:
• An RCT (n = 40) found no significant difference between intra-articular corticosteroid injections and placebo in terms of pain relief, joint stiffness, joint tenderness, or patient and physician global assessments at 12, and 24 weeks after injection.
• Safety:
• No serious adverse effects were reported in the included studies.
• The experts in the guideline development group agreed that:
• The risks associated with intra-articular corticosteroid injection are generally small.
• A small percentage of people may experience a transient increase in pain following injection.
• Subcutaneous deposition of steroid may lead to local fat atrophy and cosmetic defect.
• Care should always be taken when injecting small joints (such as finger joints) to avoid traumatizing local nerves.
• There is a very small risk of infection.
• The question of steroid-arthropathy (i.e. whether intra-articular steroids may increase cartilage loss) remains controversial; concern is currently based on animal models and retrospective human studies. Caution should be applied if injecting an individual joint on multiple occasions, and other osteoarthritis therapies should be optimized.