Various research has investigated the preference for conservative care versus surgical decompression for sciatica from a herniated disc. Here we give a synopsis of the latest bout, and you don’t even need pay-per-view…
About 11% of patients visit their PCP for sciatica, and it has previously been proven that conservative measures really do work. About 80% of patients improve with conservative care over many months. However, one of the problems with lumbar disc herniation is that many afflicted are aged 40-45 years old, so there a loss of livelihood if not managed quickly. Time is money, and time is enjoyment.
Even with just observation (literally doing nothing), some disc herniations can resorb by themselves, like a bruise disappearing on your arm or leg. Most sequestered discs (a piece of the disc, free fragment, has completely broken off from the main disc) completely resolve after 9 months whereas extruded discs (piece of disc mostly out but the inner core still attached) completely resolve after 12 months. Disc herniations trigger an inflammatory response in which immune cells degrade the disc fragment. In fact, the larger the disc fragment, the more likely the body is able to eat it up like Pacman.
Therapy and yoga help ease the symptoms of a disc herniation, by strengthening core musculature. These modalities work, but simply by treating pain while the body disintegrates the disc.
Providers used to inject materials, like chymopapain, into disc herniations. This substance physically degrades the disc (chemonucleolysis) and patients improve for a while. However, they often developed worse disc disease later, likely secondary to the chymopapain’s effect on the normal disc too. This is why chemonucleolysis lost favor years ago.
Spinal injections, including epidural steroid injections, have been used for a while. The first was performed in Paris around 1900 with cocaine. While used to numb legs since the 1880s for various reasons, four patients were described in 1901 to treat their sciatica. Later, steroids were added around 1952.
Of interest, the FDA currently warns about the injection of corticosteroids into the epidural space of the spine due to risks, and they are NOT FDA approved. Let me repeat, lumbar epidural steroid injections are not FDA approved. However widespread practice for many decades has established utility. (And you may be surprised to know that there are other widespread spine procedures that aren’t FDA approved…
Some of the controversies with spinal injections are in the possible placebo aspect. A few studies have shown (including a large New England Journal of Medicine article in 2014) that lidocaine injections are no better than steroids alone, calling to question what an injection even does in the setting of disc herniation. It traditionally was thought that patients have symptoms primarily from inflammation induced by compression on the nerve. After all, the mere presence of a disc herniation means nothing… even completely asymptomatic people have disc herniations. However release of inflammatory factors, a cytokine-mediated immune response, causes the pain. Why some patients release inflammatory markers causing symptoms, and others do not, may not be fully understood. But if steroids are not integral to the effectiveness of spinal injections, then why do they work? Just like with the Tootsie Pop… the world may never know.
Surgery is very effective. Surgery and time are the only two legitimate options for physically separating a disc fragment from the nerve. A 2016 British Medical Journal article indicated that surgery has been shown to provide faster relief from lumbar disc herniation symptoms compared to conservative approaches. A 2020 NEJM study assessing 790 patients showed that when sciatica lasts more than 4 months, surgery was superior with respect to pain intensity at 6 months. Yet there are risks to surgery too.
A recent NERVES study in Lancet was published as a multicenter, phase 3, randomized controlled trial. Participants were randomly assigned to transforaminal epidural steroid injection (80) or surgical decompression (83). Leg and back pain, as well as disability scores, at 18 weeks was more improved in the surgery group, but to a non-statistical level. There were 4 serious adverse events in the surgery group and none in the steroid group. Surgery was more expensive.
Therefore it appears that surgery may be slightly more efficacious for symptoms, but slightly riskier and costlier. Transforaminal epidural steroid injection should at least be considered as a first invasive treatment option, prior to surgery. However, going straight to surgery may be reasonable in certain cases too.
This match of conservative options versus surgery goes to the judges… it may be a draw.