 |
| R subacromial bursa |
A bursa is small sac (or bag) filled with fluid. They act like thin shock absorbers between the bones and other moving parts of the body like muscles and tendons to reduce friction. When a bursa gets irritated (or inflamed) it fills up with more fluid resulting in a condition called bursitis. We have many bursae (plura for bursa) in our hip, elbow and knee joints.
Researchers reviewed video images of ultrasound guided corticosteroid injections to rate the accuracy of injection into 3 groups. Group 1: Definitely/ probably not in the subacromial bursa. Group 2: Probably in the subacromial bursa and Group 3: Definitely in the subacromial bursa.
There were a total of 114 subjects. 22 were categorised in Group 1, 21 into Group 2 and 71 in Group 3. I definitely expected the subjects in Group 3 to have the best result, but I was wrong.
Results showed that there were no significant differences between the 3 groups at 6 weeks. So, no clear evidence that accurately injecting the subacromial bursa under ultrasound guidance is better than missing it. Even if the injections were done *blind versus guidance by ultrasound!
*Blind means the injection is done at the point where the patient says the pain is versus using ultrasound to guide the injection into the correct inflamed area.
The authors concluded that the accuracy of injection placement in shoulder impingement did not influence pain and function suggesting that improvements in patients' outcome did not require ultrasound guidance.
Perhaps there is no difference in outcomes possibly because neither 'blind' nor ultrasound guided corticosteroid injections work in the medium to long term. The sample size is small and follow-up period is too short. Plus y'all know how I feel about steroid injections.
Another systematic review also investigated ultrasound guided versus landmark injections for rotator cuff related pain (Adamson et al, 2022) and came to the same conclusions.
Will these findings affect the doctors/ surgeons who charge more using ultrasound guided injections compared to doing the injections 'blind'?
And another paper (Marshall et al (2023) showed that the subacromial bursa promoted an early inflammatory response in an injured tendon to help healing. Using a rat to model rotator cuff injury and repair, the bursa protected the tendon adjacent to the injured tendon and maintained the structure of the underlying bone.
I do not normally consider results from obtained from animal studies usually (rats in this case), but am persuaded in this case as every time a 'diseased' or damaged body part is deemed worthy of removal or function suppressed, we find out later it is a bad idea. Like our tonsils and meniscus.
Inflammation and healing are definitely misunderstood. Our busae release essential inflammatory fluid/ cells for help our injured tendons recover. Injecting them with cortisone/ steroids means hindering the body's own healing process and harming your own tendons. Think of it as the human body is being programmed to sort out its own injuries.
References
Adamson N, Tsuro M and Adams N (2022). Ultrasound-Guided Versus Landmark-Guided Subacromial Corticosteroid Injections For Rotator Cuff Related Shoulder Pain: A Systematic Review Of Randomised Controlled Trials. Musc Care. 20(4): 784-795. DOI: 10.1002/msc.1643
Chean CS, Raval P, Ogollah RO et al (2022). Accuracy Of Placement Of Ultrasound-Guided Corticosteroid Injection For Subacromial Pain (Impingement) Syndrome Does Not Influence Pain And Function: Secondary Analysis Of A Randomised Controlled Trial. Musc Care. 20(4): 831-838. DOI: 10.1002/msc.1634
Marshall BP, Ferrer XE, Kunes JA et al (2023). The Subacromial Bursa Is A Key Regulator Of The Rotator Cuff And A New Therapeutic Target For Improving Repair. bioRxiv (Preprint). July 2. DOI: 10.1101/2023.07.01.547347
No comments:
Post a Comment