Treating Sciatica with Epidural Intervention

Lower back pain or sciatica is often treated with epidural injections that include corticosteroids. These injections provide fast relief for acute cases and can be an alternative to spinal surgery for patients who are unable or unwilling to undergo the procedure.

Some individuals with chronic pain regularly visit pain clinics to receive repeated injections for their condition.

History

Around 1900 in Paris, epidural injections were first administered using cocaine instead of corticosteroids. This research paper investigates the origins and development of these injections, specifically examining their transformation from a modest laboratory procedure to a widely embraced medical treatment worldwide.

The primary goal is not solely to delve into historical facts but to comprehend how this therapy has flourished despite ongoing discussions about its efficacy and safety concerns.

The question of who treated the first patient with an epidural pain injection in the lower back is a subject of debate, with two competing claims. Jean-Anasthase Sicard made the first public mention of these injections during his address to the Societé de Biologie in Paris on April 20, 1901.

However, prior to Sicard’s speech, Fernand Cathelin from Paris had already been administering epidural injections to patients for several months. Both Sicard and Cathelin did not invent these techniques outright but rather refined existing anesthetic methods that were previously described by James Corning from the United States and August Bier from Germany.

It’s worth noting that Figure 1 displays portraits of both individuals.

Corning is often acknowledged for performing the first direct spinal puncture in a living person in 1885. In an attempt to alleviate the effects of “spinal weakness and seminal incontinence” caused by habitual masturbation,

Corning injected a cocaine solution into the epidural space at the T11-T12 level. In 1895, Bier successfully induced lower body anesthesia by injecting a cocaine solution into the intrathecal space of one of his residents.

Unfortunately, this procedure resulted in complications, as the individual experienced a prolonged and severe headache lasting over a week due to low intracranial pressure.

Joining the laboratory of neurologists Fulgence Raymond and Edouard Brissaud at the renowned Hôpital de La Salpetrière in 1896, Sicard embarked on his spinal research.

His project had two primary aims: first, to approach the study of the spine from a clinical standpoint rather than focusing solely on anatomy or physiology, and second, to introduce the practice of injecting medicinal fluids into the spine instead of extracting cerebrospinal fluid through lumbar puncture.

Sicard’s work was influenced by the prior contributions of Corning and Bier in the field, shaping his approach to spinal research.

Utilizing animal experimentation as a starting point, Sicard ventured into his research. By injecting a small amount of cocaine, he achieved successful lower body anesthesia in dogs.

Unlike Bier’s approach, Sicard adopted the “caudal route,” bypassing lumbar vertebrae and instead accessing the sacral roots through the first dorsal sacral foramen. This method involved carefully preserving the outer layer of the meninges and specifically targeting the epidural space.

To refine his skills, Sicard replicated these injections on human cadavers. Eventually, he progressed to administering such injections to patients suffering from pain, applying his expertise in a practical setting.

Sicard shared the clinical outcomes of nine patients during a Societé de Biologie meeting in Paris on April 20, 1901. Among these cases, two individuals were afflicted with syphilitic myelopathy, two suffered from low back pain, and four presented with sciatica. Notably, the treatment administered by Sicard was not only devoid of pain and risk but also yielded significant success.

Famed as a prominent “pain doctor,” Sicard made significant contributions in the field. During World War I, he conducted alcoholizations to alleviate peripheral nerve injuries, specifically targeting causalgia.

Sicard’s pioneering work extended to contrast radiology, where he collaborated with Jacques Forestier to perform the first epidurogram. In contrast, Cathelin’s interests lay primarily in surgery and anesthesia, with less emphasis on pain management.

In 1925, Viner from Montreal adopted the caudal approach, substituting cocaine with novocain. He administered multiple injections to patients suffering from sciatica, leading to notable pain relief and favorable results.

Notably, the herniated disc, which is now widely recognized as a common cause of sciatica, was not widely acknowledged until 1934, when Mixter and Barr introduced this understanding.

In 1930, Evans employed the caudal injection technique with normal saline and procaine hydrochloride to treat 40 patients diagnosed with “idiopathic sciatica.” This treatment resulted in complete relief for 24 patients and notable improvement for 6 patients.

Evans’s innovative approach included the use of larger volumes, showcasing the diffusion of 100 ml of fluid throughout the spinal canal by injecting it at the base of the sacrum.

Cortisone, or “compound E,” was discovered in the early 1920s through Mayo Clinic research. Post-World War II, corticosteroid treatment yielded remarkable results for rheumatoid arthritis.

Italian rheumatologists Robecchi and Capra suggested that inflammation could also contribute to low back pain and sciatica. Successful cases involved hydrocortisone infiltration into the first sacral nerve root.

Further studies, such as Lievre et al.’s use of hydrocortisone for sciatica and Goebert et al.’s report on epidural corticosteroids in the United States, followed.

Uncontrolled trials between 1950 and 1990, summarized in Table 2 [21-29], focused on epidural corticosteroid administration for sciatica treatment. Intrathecal injections declined due to meningitis risk. Despite limitations, these studies influenced corticosteroid use for sciatica.

Conflicting results emerged from the first randomized controlled studies in the 1970s. A consistent positive response to epidural corticosteroids for sciatica remains elusive.

Present Status

The technique and applications of epidural injections have evolved over time, with variations in anesthetics and glucocorticoids used. The trend has shifted towards interlaminar and transforaminal injections guided by fluoroscopy.

While epidural corticosteroids are commonly administered for various spinal conditions, their effectiveness specifically for sciatica is supported by limited evidence. Safety studies have identified both common side effects and rare severe complications.

The FDA has issued warnings and implemented safety measures, prompting discussions among experts about the associated risks and necessary precautions. The ongoing debate surrounds the class warning for lumbar epidural injections.

The global spread of epidural injections was slow compared to other medical ideas. The introduction of corticosteroids and positive clinical trials in the 1960s and 1970s contributed to their popularity, despite limited scientific evidence.

More data and consideration of safety issues are needed. Severe complications from lumbar epidural injections for back pain and sciatica are rare.