Injectable Gel May Be Long Term Solution to Chronic Low Back Pain

By Pat Anson

An experimental hydrogel continues to show promise as a long-term treatment for chronic low back pain caused by degenerative disc disease.

Findings from a feasibility study, recently published in the the journal Pain Physician, show that 60 patients with low back pain had significant improvements in physical function, low back pain, and low leg pain a year after Hydrafil gel was injected into their damaged discs.

The gel is heated to liquify it before being injected into cracks and tears in discs. It hardens as it cools, restoring the discs’ structural integrity. The procedure takes about 30 minutes and can be performed as an outpatient procedure under local anesthesia. 

Unlike other cement-like material injected into damaged discs to restore stability, the gel remains flexible and mimics the biomechanical properties of the natural disc, preserving spinal motion. 

Most patients showed significant improvement in their pain and disability scores within one month, and the results were maintained 12 months later. 

“These peer-reviewed results represent an important milestone in the development of the first nucleus augmentation technology for degenerative disc disease,” said Douglas Beall, MD, Chief of Radiology Services at Clinical Radiology of Oklahoma and a medical advisor to ReGelTec, which developed the Hydrafil system. 

“The improvements in pain and function observed at one year, along with an acceptable safety profile, support the continued evaluation of the HYDRAFIL System in the ongoing pivotal study designed to support FDA approval of the device for patients who currently have limited minimally invasive treatment options.”

Five of the 60 patients had increased back and leg pain or numbness, due to the gel partially migrating beyond the injection site. The migrated gel was later removed.

This promotional video by ReGelTec demonstrates how the Hydrafil system works:

ReGelTec is currently recruiting 225 patients in the U.S. and Canada for a new study to assess the Hydrafil system, an important step towards getting FDA approval. 

Hydrafil received the FDA’s breakthrough device designation in 2020, which allows for an expedited review of an experimental product when there is evidence it is more effective than current options.  

Degenerative disc disease is one of the leading causes of chronic low back pain. Healthy discs cushion the spine’s vertebrae, supporting movement and flexibility. But with aging and activity, discs can wear out and cause the bones of the spine to rub together and pinch nerves, causing pain and numbness. By age 60, most people have at least some disc degeneration in their spines.

Current treatments for degenerative discs include physical therapy, anti-inflammatory medication, and analgesics. When those are insufficient, epidural steroid injections and surgical options such as a disc removal or spinal fusion may be considered.

Why Oral Opioids Can Give Poor Pain Relief

By Forest Tennant, PNN Columnist

Every day, our Research and Education Projects hear from persons with a serious pain problem who can’t obtain enough relief. There are multiple reasons, but a major one is that they are trying to relieve their pain with oral opioids. It appears to us that there is a gross misunderstanding and ignorance about the inability of oral opioids to ever provide good pain relief in many persons who have Intractable Pain Syndrome (IPS).

A person who has constant pain from adhesive arachnoiditis, Ehlers-Danlos Syndrome (EDS), Reflex Sympathetic Dystrophy (CRPS/RSD), cervical neck neuropathy, or another disease that causes constant pain with cardiovascular and endocrine abnormalities will often have impairment of the stomach and intestine. This affects their ability to properly dissolve, digest and place enough opioid into the bloodstream to get pain relief. This occurrence is technically called “opioid malabsorption” or “opioid maldigestion.”

All the conditions listed above cause dysfunction of the many nerves that go from the spinal cord to the stomach and intestine. The nerves carry the bioelectricity that activates the stomach and intestines so that the acids and enzymes from them will fully dissolve and digest tablets, capsules and liquids. EDS, diabetes and autoimmune diseases may also erode or degenerate the collagen matrix of the small intestine, so it won’t properly function, which impedes digestion.

Stomach and intestinal malfunction due to many severe painful diseases may manifest differently at different times. For example, on some days function will be good, and on others, almost non-existent. Another example is “maximal ability.” In this case, the impaired stomach and intestine will allow only a maximal amount of opioid to be digested. For example, 4 tablets will provide some relief, but 6 or 8 won’t do any better.

Review your situation. Do you have some days when you got relief, but not others? Does increasing your oral dose give you no more relief?

If you have IPS, don’t always count on oral opioids to give you the pain relief you need. Start looking into opioid injections, suppositories, patches, topicals, sublingual (under-the-tongue), or buccal (inside the mouth-upper cheek). Also, start probiotics and/or intestinal enzyme preparations, as they sometimes help oral opioids do their job.

Injectable and Suppository Opioids

Why aren’t injectable and opioid suppositories the standard care for severe pain flares? They used to be. For example, the 1956 Merck Manual (9th Edition) states “more severe pain requires the oral or subcutaneous use of narcotics.”

Today, most doctors somehow have the irrational and false idea that injectable opioids always cause overdoses and/or will be diverted into illegal channels. Most doctors are hardly aware that opioid suppositories are available from the local pharmacy and that they are far more effective for flares or breakthrough pain than oral opioids.

At best, an oral opioid will need 30 to 60 minutes to provide pain relief. Opioids administered by injection or suppository work much faster, bypassing the stomach, intestines and liver, and going right to the blood brain barrier.  Pain relief will usually occur within 5 to 10 minutes. Pain relief is also much better, even at a fraction of the oral dose, because the entire dosage reaches the endorphin receptors without being filtered by the stomach, intestines and liver.

Opioid injections and suppositories help patients remain below the CDC guideline’s recommended daily limit of 90 morphine milligram equivalent (MME).

Injectable opioids are used subcutaneously or intramuscularly, not intravenously, for at home use. Injectable
opioids should only be used for flares.

Our enthusiasm for injectable opioids has been enhanced by the development of compounded hydromorphone. This innovation allows a micro dose of only .1cc (5mg), which can be taken subcutaneously with a small needle.

Opioid injections have traditionally been prescribed by local primary care practitioners who know the patient is responsible, and not a street person or substance abuser. Patients and their families should also be trained and warned to keep the injectable away from children, pets and guests. We are not aware of a single case of injectable opioid reaching the street or causing an overdose death in a bona fide IPS patient who was trained with their family.

IPS patients and families can inquire at their local pharmacy as to which injections and suppositories are available. Then approach your personal MD, DO, or NP about starting an opioid injection or suppository for pain flares. 

Every IPS patient needs to achieve some pain free hours so they can walk, physically exercise their arms and
legs, do activities of daily living, and be able to mentally concentrate enough to be able to read and write. These hours of zero or very little pain help strengthen the cardiovascular and endocrine systems so some tissue regeneration can occur and permanently reduce their constant pain. Injectable opioids provide the best opportunity at achieving some pain free hours.

Forest Tennant, MD, DrPH, is retired from clinical practice but continues his research on intractable pain and arachnoiditis. This column is adapted from newsletters recently issued by the IPS Research and Education Project of the Tennant Foundation. Readers interested in subscribing to the newsletter can sign up by clicking here. The Tennant Foundation gives financial support to Pain News Network and sponsors PNN’s Patient Resources section.