Study finds no advantage of specialised knee injections over saline

New research published in The Bone and Joint Journal challenges claims about specialised knee injection treatments for arthritis. The study found that a blood-based treatment showed no benefits over simple saline injections, and in some measures performed worse.

The research in detail

Scientists conducted a rigorous clinical trial comparing two treatments for knee osteoarthritis. In the trial, one group received nSTRIDE (an Autologous Protein Solution or APS) whilst another group received saline solution injections. A total of 40 patients with moderate knee arthritis participated in the research, which followed patients for 12 months. To ensure the most reliable results, neither the doctors nor patients knew which treatment they received, making this what researchers call a 'double-blind study'.

Key findings

The research revealed several important outcomes. There was no significant difference in overall knee function between the two groups. More notably, pain scores were actually better in patients who received saline. At 12 months, patients who received the specialised treatment reported worse pain both during rest and during their most painful moments. However, the study found no safety concerns with either treatment.

What is APS treatment?

Autologous Protein Solution (APS) treatment is a procedure that involves taking blood from a patient's arm, processing it to concentrate anti-inflammatory factors, and then injecting the resulting solution into the knee. The treatment is marketed as potentially reducing inflammation and improving cartilage health.

Current guidelines

The National Institute for Health and Care Excellence (NICE) does not recommend these types of injections for routine treatment of knee arthritis. This research supports this position by demonstrating that the specialised treatment offered no advantages over saline, and that simpler treatments may be equally or more effective. The claims of superior benefits were not supported by the evidence.

What this means for patients

If you are considering treatment for knee arthritis, it is important to discuss evidence-based options with your healthcare provider. The research suggests that simpler treatments might be equally effective, and that even saline injections can provide temporary relief due to the placebo effect. It is worth noting that NICE guidelines do not support routine use of these specialised injections.

Reference: Ross M, Zhou Y, English M, Sharplin P, Hirner M. The effect of intra-articular autologous protein solution on knee osteoarthritis symptoms: a randomised clinical controlled trial. The Bone and Joint Journal. 2024; 106-B 9; 907-915.

This article was adapted from a blog post by Ian McDermott, Consultant Orthopaedic Surgeon specialising purely in knees.

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