Sciatica Back Epidural or Caudal – 40 mg Steroid as Good as 80 mg.

In two separate studies, there seemed to be no advantage to using 80 mg steroid over 40 mg. If one stuck to 40 mg, then one could have a shot every 6 weeks, rather than having to wait 3 months for another shot.

First study:
Singapore Med J. 2007 Mar;48(3):241-5.
Comparison of two doses of corticosteroid in epidural steroid injection for lumbar radicular pain.
Owlia MB, Salimzadeh A, Alishiri G, Haghighi A.  free article here

• 84 cases of sciatica
• 80 mg and 40 mg Depo-Medrol
• Epiduralography proved the access of the drug
• Results (assuming start VAS of 7)

•  Given that epiduralography shows side locked perfusion of meds in 20% of cases and side dominant in 50%, satisfactory epiduralography would have increased results by ?maybe 25% = VAS 1.75
• Maybe 80 mg would work better if injected on the wrong side of epidural septum?

Caudal Block Experience:

Anaesthesia. 2011 Jul;66(7):595-603.
A pilot study of the dose-response of caudal methylprednisolone with levobupivacaine in chronic lower back pain.
McCahon RA, Ravenscroft A, Hodgkinson V, Evley R, Hardman J.  abstract here

• small – 33 cases
• almost all cases had leg pains as well but poorly defined as true sciaticas
• No mention of Pain VAS response just Oswestry results
• Hard cases – mean duration 18.9 years
• added 10 ml levobupivacaine 0.25% and 10 mls saline to bring volume to 20 mls
• “loss-of-resistance technique was used to identify the epidural space via a caudal approach.” – that would mean sticking with an 18 gauge touhy – ouch!
• No mention of whether they were kept on bad side for 20 min after (which can double response rate).
• Results were on basis of an Ostwestry disability scale of questions – Must admit I am leery of multiquestion scales – a little bit better on several question amounts to a whole lot better on a scale when it might not be…

Results by disability:

Another interesting possibility is the use of just soluble steroid;

Clin J Pain. 2011 Jul-Aug;27(6):518-22.

Efficacy and safety of lumbar epidural dexamethasone versus methylprednisolone in the treatment of lumbar radiculopathy: a comparison of soluble versus particulate steroids.
Kim D, Brown J.  abstract here

• 30 cases each group; pain for at least 6 months
• followup 41-51 days
• Depo-medrol 80 mg or Dexamethasone phosphate 16 mg
• 2 mL of 0.25% preservative free marcaine and preservative free saline up to a total volume of 10 mL.
• Confirmatory epidurogram.

• I’m afraid there is no local by self placebo group so cannot know for sure…

What one needs as some way to insure epidural gets to the correct side of the epidural septum – I believe what is needed is the use of  paramedian approach – out more lateral and aim to epidural space. – goes in 1 cm deeper – instead of about 40 mm – more like 50 mm depth – but needle would be facing the right side if went in from opposite to pain side. Comment –  Winners include a paramedian approach with 40 mg depo steroid (I like to use kenalog that has settled and the preservative pre-sucked off). Or caudal with 40 mg in 10-20 mls total volume. Using epidural/caudal  or intrathecal ph-neutralized midazolam 2-5 mg could be used in between to sustain effect.

In the end I am still left with the question “Didn’t anybody bother turning out the lights? – There is going to be tremendous amount of muscle knot issues just left up in the air – Quadratus lumborum/Psoas, Thoracolumbar Quadratus Lumborum/Lumbar plexus and gluteus medius, and piriformi – working those out when central contributors are relatively inactive could multiple the results… which is why results of epidurals are controversial – no one bothers to turn out the lights.  These knots will remain – one study found thoracolumbar paraspinous triggers remained there for years after having passed a kidney stone on that side – still knotted, waiting for muscle work or injections to de-knot them…

Any comments?