The pain caused by the irritation of the sciatic nerve is quite common and has an annual incidence of 1-5 % annually and 10-40% in the lifetime (1). It is highly troublesome and its peak incidence is in the 4th decade(2).
The pain itself originates at the Lumbosacral plexus where any compressionthat may occur between the nerve roots of L4- S2 which bundles up in the pelvis to form the sciatic nerve. This nerve is probably the thickest nerve of the body and can be of up-to 2 cms thick. The nerve travels all the way from the upper gluteus muscle to the plantar aspect of the foot. The trajectory provides for motor activity to the hamstrings, adductors of the lower extremity, the calf muscles , anterior leg muscles and the intrinsic foot muscles. This nerve also provides sensory activity to the leg’s lower lateral, posterior regions and also the plantar aspect of the foot.
It is believed that generally the irritation may result from some types of inflammatory conditions but any of the more direct compression leads to a more severe motor debilitation.
The simpler risk factors involve mental stress, smoking, height and ages between 45 and 64. Occupational factors such as driving very vibration producing equipments such as trains, trams, trucks and auto buses along with other occupations that have repetitive bending and twisting or heavy lifting may be some of the causative factors. Other factors such as tumour, bipartite piriformis or inferior gluteal artery aneurysm may also compress the nerve (3).
The most salient of the causative etiology is the intervertebral disc prolapsed generally from trauma or from sciatic nerve entrapment at the anatomical region anterior to the piriformis muscle or posterior to the gemelli-obturator complex proximal to ischial tuberosity aka Piriformis syndrome(4).
The diagnosis is based on imaging such as MRI or CT Scans and coincidental disc hernias may be found in 20 – 36% without presentation of any signs or symptoms. Clinically the straight leg raise test or LASEGUE test along with Bragard’s sign or Neri’s sign being confirmatory for dural pathologies such IVD prolapse or tumours of the spine
Clinically the recovery is favourable with conservative therapies rather than intervention with injectables and currently the trends are to avoid surgical interventions which as per certain reviews may give instant gratification post operatively but studies show that there is not much difference between conservative therapy in the long run(5) .
Opioids, analgesics and NSAIDS have shown that there is an additional danger of addiction which has more severe long-term sequelae in the society.
While approaching the conservative treatment allowing the sleeping tiger sleep is the best attitude as any forceful manoeuvre and positioning may exacerbate the condition. As per new research the bed rest and analgesia has been reciprocated with more activity and stretching ; Yoga seems to be the most gentler of the exercise regimen and I have found an excellent article in www.healthline.com with demonstration written by David Heitz and Erica Cirino and reviewed by Amy Elizabeth Wolkin, PT,DPT, MBA. I recommend all who are interested to read the following article https://www.healthline.com/health/back-pain/sciatic-stretches#What-is-the-sciatic-nerve?
In my opinion the slow and gentle manipulations such as used in Osteopathy and Naprapathy is more recommendable rather than the heavier and abrupt procedures used by the proponents of HVLA thrusts .
Bibliography
1) Davis D, Maini K, Vasudevan A. Sciatica. [Updated 2022 May 6]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK507908/
2) Davis D, Maini K, Vasudevan A. Sciatica. [Updated 2022 May 6]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK507908/
3) Koes, B.W., van Tulder, M., Lin, CW.C. et al. An updated overview of clinical guidelines for the management of non-specific low back pain in primary care. Eur Spine J 19, 2075–2094 (2010). https://doi.org/10.1007/s00586-010-1502-y
4) Hicks BL, Lam JC, Varacallo M. Piriformis Syndrome. [Updated 2022 Apr 21]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK448172/
Koes BW, van Tulder MW, Peul WC. Diagnosis and treatment of sciatica. BMJ. 2007 Jun 23;334(7607):1313-7. doi: 10.1136/bmj.39223.428495.BE. PMID: 17585160; PMCID: PMC1895638.
pictures taken by Dr.Deepak Pal.
Comments