Deep Gluteal Syndrome
Surgical nerve decompression of the nerve has a place for some patients. There are grounds for believing that surgery has more than placebo effect. Corroboration is provided by preoperative findings, such as piriformis muscle hypertropy on MRI, confirmation at operation and improvement after operation. Patients who had not responded to conventional surgery have improved after decompression of the nerve. and in In one series of 60 patients, not only did pain improve after surgery but so did the specific tension tests suggesting that release of nerve compression had been achieved. Unfortunately, incomplete reporting by the authors means that the objectivity of the assessments cannot be guaranteed.
Conservative treatments parallel those recommended for musculoskeletal conditions in general: physiotherapy, local injections, and acupuncture. Physiotherapy takes the form of stretching muscles and mobilisation exercises. No controlled trial of physiotherapy could be found on searching several databases, including the specialist physiotherapy site, PEDro.
Local anaesthetic (LA) and steroid combinations (CS) have been used for many decades, in the same way that they have been used for other nerve compression and musculoskeletal disorders . More recently, injection of botulinum toxin into muscles has been investigated. Injections can be performed under ultra sound guidance. The evidence for injection therapies comes largely from case series, that is, unblinded studies without control subjects or poorly reported trials. Well designed and well reported RCTs were found but each had a small sample and a largely irrelevant comparison. They are described here. Each compared different techniques, e.g. LA against LA+CS, and found no difference whereas what clinicians and patients need to know is how does a treatment compare to placebo. Randomised controlled trials of injection therapy are described here
A major problem in research is the absence of opportunities for profit from pharmaceutical sales means that well designed RCTs are less likely to be funded.
What to do with the current level of knowledge?
Physiotherapy has the advantage of being the least invasive treatment. Furthermore, referral is concordant with current NICE guidance for persistent sciatica. Patients capable of accessing video can be directed to a demonstration of home exercises at nhs.uk