Yet further evidence against the joint injection scam!
The effect of intra-articular autologous protein solution on knee osteoarthritis symptoms
Ross et al.
The Bone and Joint Journal. 2024; 106-B 9; 907-915. https://pubmed.ncbi.nlm.nih.gov/39216848/
There is a plethora of ‘stuff’ that some people seem happy to inject into patient’s knees. This is partly driven, no doubt, by clinicians’ desire to try and help patients, even in situations where ‘no specific intervention’ (or just activity modification / rest) might actually be the best option. The more cynical (awake!) amongst you might question the potential influence of The Pharmaceutical Industry (‘Big Pharma’!) and the undue influence they exert through marketing, through financial incentives and through the adverse influence that they so often seem to exert on the published research (much of which they fund!). Very sadly, on top of all this, there are undoubtedly some clinicians out there who simply see joint injections as a very lucrative business, and who seem more than happy to inject ‘any old stuff’ into anyone’s knee, just to make an easy fast buck!).
Of the long list of potions and ‘magic pixie dust’ that some people seem prepared to tout to the unsuspecting public (and, in particular, to uninformed, desperate and hence vulnerable patients), one type of product is PRP (platelet-rich plasma). There are several different versions of PRP in clinical use, but fundamentally, they are all similar, in that they involve taking blood from a patient’s arm, spinning the blood to remove various things, such as the red blood cells +/- the white cells, and then injecting the solution back into the knee, on the premise that the couple of millilitres of fluid that is produced somehow contains ‘magic growth factors’ that supposedly somehow ‘slow down the arthritis and reduce patients’ pain’.
Importantly, there is very poor evidence to support the use of PRP injections into knees for the treatment of early arthritis. Undoubtedly, injecting anything into a knee can have a positive effect simply due to the placebo effect (if you simply inject just saline into people’s knees, about 40% of people report a (temporary) improvement in their knee symptoms!). However, there is no decent evidence that PRP injections make any significant difference to the long-term prognosis of an arthritic knee, either in terms of symptoms or the likelihood of the patient ending up needing a knee replacement.
This is why PRP injections are not recommended by NICE for the treatment of knee arthritis (not without ‘special arrangements’ being place).
(And this is also why some people believe that the true meaning of ‘PRP’ is actually ‘Pointless Rich Physicians’!!?!)
One ‘special version’ of PRP is something called nSTRIDE – which is referred to as an ‘APS’: an ‘Autologous Protein Solution’. With this, 60ml of venous blood is taken from the patient’s arm. The blood is then spun in a centrifuge. This is then said to leave 3ml of ‘protein-rich fluid’ (quite how this leaves behind the ‘good proteins’ I have genuinely no idea!!?! – and I’ve scoured the internet for a decent logical scientific explanation of just how this might actually work… but so far, have found none!)… and the 3ml of fluid (AKA blood, but without the cells) is then injected into the knee.
The company that sell nSTRIDE state that it is:
“a cell concentration system that is designed to concentrate anti-inflammatory cytokines and anabolic growth factors… to significantly decrease pain and promote cartilage health”.
Some clinicians market these injections with statements such as:
“The nSTRIDE APS injection treatment is designed to alleviate pain and bring balance back to your inflamed knee joint by introducing high levels of “good” proteins concentrated from your own blood. These good proteins can block the “bad” proteins responsible for the inflammatory condition in your joint. At the same time, nSTRIDE APS also concentrates growth factors which are beneficial for cartilage health.”
with claims that:
“nSTRIDE is the only single-injection therapy where the benefits are sustained for up to 3 years.”
So, what does this latest study from Ross et al actually show?….
Well, in this high-quality prospective randomised study, the authors took 40 patients with unilateral moderate osteoarthritis on the knee. They randomised 21 to having an nSTRIDE injection in their knee versus 19 whose knees were simply injected with saline (placebo). The patients were followed up for 12 months, and the authors found the following:
- no significant differences were found between nSTRIDE and placebo for any of the standard knee scores used (the WOMAC knee score and the KOOS knee score), but
- The pain scores were actually lower in the placebo group!
So, this high-quality study shows that not only does nSTRIDE not work… but that simply injecting saline as placebo gave better pain reduction than nSTRIDE!!!
In conclusion
There are an awful lot of companies and clinicians making a lot of bold and unsubstantiated claims when it comes to joint injections, and it is clear that ‘the joint injection market’ is a highly-lucrative money earner for some less-scrupulous individuals.
If you want to STAY SAFE…. then STAY SCEPTICAL! … Do your reading and do your own research… and if a suave medical salesman tries to sell you a magic cure that sounds too good to be true… then guess what: it’s not true!
I just hope that one day the medical profession will drain the swamp of some of the individuals out there who are clearly doing things for their own benefit (for the benefit of their bank accounts) rather than acting in the best interests of their patients!