In over 25 years of spine surgery, I don’t think I’ve seen a diagnosis missed more consistently than chronic low back pain caused by annular tears. The MRI misses annular tears about 50% of the time or more, and with a negative MRI, most physicians stop looking for a cause of back pain at that point.
Annular tears refer to an injury to the disc that acts as a cushion between the vertebrae of the spine. The disc acts as a cushion with a soft center and a thick covering that attaches to the bone of the vertebrae.
The soft center of the disc can be likened to an Oreo cookie with a tendency of the filling to displace outward with any pressure applied; and as long as the annulus remains intact, there is no escape of the filling of the cookie. However, a combination of forces exists in the discs of the lumbar spine which in combination can result in significant deterioration and pain. These factors include continuous motion forces being applied to the lumbar spine without ever a chance to completely stop moving and heal. The second is a very poor blood supply to the disc and annulus. The blood supply to the disc comes through the endplates of the vertebrae, which is limited in its ability to repair any injury quickly; and there are significant forces continuously being applied to the discs of the lumbar spine with just general movement, positioning, and any type of trauma.
From Dr. Mork’s research: In patients with confirmed annular tears on CT discogram, the tear was not reported on MRI in 50% of cases. A normal MRI does not rule out an annular tear.
What Are the Symptoms of an Annular Tear?
The most common complaint is deep midline back pain — usually worst with sitting, especially driving. People can have pain radiating to the buttock, sacroiliac joint area, coccyx, and groin area as well as the thigh and/or leg; but this is not a consistent finding. The radiating pain in the lower extremities is often accompanied by burning. The other consistent finding is back pain that waxes and wanes; in other words, it can be fine for weeks or even months and then just go out for no apparent reason, usually with some rest. That cycle will continue to repeat itself often for years and oftentimes gets more frequent with time.
What is the typical history given by a patient with an annular tear?
There are seven typical complaints:
1
The back pain is usually deep in the middle and gets worse with exercise or physical therapy. Chiropractic adjustments can help for a short time, but the pain usually returns within days. Decompression devices do not seem to help. They may help temporarily but not for long term.
2
“My back goes out” — My back can be fine for months and then it will go out for no reason. When it goes out, I’m really disabled for a few days or a couple of weeks. I’ve had this problem for years.
3
Sitting for any length of time is very painful, especially when driving.
4
“I’ve seen 3 or more doctors and they all say my MRI looks normal” — and they recommend I just live with the pain, do more therapy, or go to pain management.
5
Groin or testicular pain, but my doctor tells me my hips are normal and I don’t have a hernia.
6
Pain pills might take the edge off for a short period of time, but don’t really help.
7
Intermittent pain, numbness, or burning in one or both of my legs, buttocks, or feet — but I don’t have a herniated disc.
+
Failed a course of physical therapy or pain management with persistent deep midline pain in spite of physical therapy or pain management.
If you see enough doctors who don’t understand what the problem is, they will begin to question your sanity.
Do These Sound Familiar?
Check the ones that apply. This isn’t a diagnosis — but it can help clarify what to discuss with Dr. Mork.
In my experience with annular tears, I get more information from a history that includes the proper questions about symptoms than an MRI usually reveals.
Why Annular Tears Cause Pain
There are four main reasons that annular tears hurt:
1
Not enough blood supply to allow healing.
This is further aggravated by the fact that the disc is almost always moving.
2
Disc material interference.
The tear may not be able to heal itself because some disc material is wedged in the tear so that the edges cannot approximate.
3
Inflammatory chemicals.
A high-grade tear may allow passage of inflammatory chemical mediators from inside the disc (nucleus) to the outer ⅓ of the annulus where there are nerves that are very sensitive to these chemicals.
4
Healing of an annular tear brings in new nerve fibers.
This occurs from the outside and carries sensitive nerve tissue in addition to new blood vessels.
The presence of these chemical mediators inside the disc can even cause big pain if the chemicals leak out of the disc and come in contact with the nerve — even with a normal appearing disc on MRI. On the other hand, around 30% of people who have never had back or neck pain have documented annular tears.
What Is the Real Problem with Annular Tears That Cause Back Pain and Don’t Heal?
Fragments of disc and cartilage that have broken off from their nutritional supply cannot get out of the disc, and they remain a chemical and mechanical reason for pain. The area when recognized is a large piece of disc being separated from its nutritional supply, creating a herniation, but no one seems to account for the fact that if the fragments are very small, they cannot escape or herniate out of the disc like larger fragments do. The blood supply to the disc is relatively poor as it comes to the endplates to supply nutrients to the disc, which is not anything comparable to a blood vessel, which would normally supply nutrients and oxygen to other soft-tissue areas and other parts of the body.
Why does the back pain remain so chronic?
1
The fragments trapped inside the disc have nowhere to go and continue to act as a mechanical issue — like a pebble in your shoe.
2
As well as causing tears of the annulus as they migrate to the periphery.
3
As they get stuck in the peripheral and annular tissues, they can actually start to degrade with chemical consequences.
The key question: What is actually causing the pain — annular tears or the free-floating fragments inside the disc? In many cases, it is both.
Why Don’t More Medical Professionals Know About Annular Tears?
Based on my many years of practicing orthopedic surgery, including more than 25 years of spine procedures, I don’t think there is a diagnosis more commonly missed than chronic low back pain caused by annular tears. Unfortunately, the correct diagnosis is needed to get the correct treatment.
This misdiagnosis has resulted in insufficient treatment, overtreatment, and incorrect treatment that isn’t effective — leaving patients to manage not just chronic pain, but the financial strain, loss of work, family responsibilities, and the mental burden of a problem that nobody can identify.
The Typical Annular Tear Patient
After hearing the same story so many times, I can often make the diagnosis over the phone. There is a very consistent history — most people just don’t understand what they are listening to.
AgeMost likely between 30–60, male or female
Primary complaintDeep midline back pain, usually aggravated by sitting — sometimes with buttock or leg pain
HistoryA minor injury where the pain never fully went away — or returns repeatedly for years
MRI resultOften read as normal, which confuses most physicians
5 Reasons the Diagnosis Gets Missed
The history is very important — and after hearing the same story so many times, I can often make the diagnosis over the phone. There is a very consistent history that these patients tell, but most physicians don’t understand what they are listening to. I would rather hear a good history than look at an MRI to diagnose an annular tear.
Most doctors look at the MRI as the definitive test for diagnosing any spine problem. However, in my research of annular tear patients, annular tears were not reported in the MRI report in 50% of cases when compared with a CT discogram of the same discs that clearly showed a tear.
This part of the physical exam is often overlooked and is a significant and consistent finding for annular tears. Pressing directly on the spinous process of the affected level will usually reproduce the deep midline low back pain — but most examiners never do this.
The literature states that the majority — perhaps around 90% — of annular tears do not cause symptomatic low back pain, so it is often dismissed as a significant cause for back pain. But the patients who do have symptomatic tears are in your office. I can’t count how many times I have seen the incorrect diagnosis of “sprain” made for an unseen annular tear.
The discogram has been labeled a potential cause of disc damage in approximately 10% of patients based on one well-written paper. However, several physicians — including myself, with thousands of discograms performed — have never observed this phenomenon. More recently there have been questions about the needle size and injection pressure used in that study. The result: the best diagnostic tool available is underused, and patients go undiagnosed.
TM
Dr. Tony Mork, MD
“I would rather hear a good history than look at an MRI to diagnose an annular tear.”
What Are the Typical MRI Findings Consistent with an Annular Tear?
1
Annular tears can be reported by the radiologist reviewing the MRI.
2
Modic changes can be associated with annular tears.
3
High-intensity zones (HIZ) can be seen on the MRI which reflect a small area of edema with water content showing up as a bright dot, which can be associated with an annular tear.
4
The most common finding on an MRI scan that correlates with an annular tear is a disc bulge, which is a very common finding in people who do not have any back pain issues whatsoever.
What Is the Gold Standard Test for the Diagnosis of an Annular Tear?
The answer is a discogram followed by a CT.
Why don’t more physicians order a discogram followed by a CT?
Are discograms dangerous?
Why does the discogram show annular tears so much better than the MRI scan?
Who can do a discogram?
Can you have a normal MRI and abnormal discogram?
What does the discogram actually show?
What is a provocative discogram?
What reporting system is used to classify discograms?
Is There Something That the MRI Scan and Discogram Don’t Show That Could Be a Problem?
My endoscopic research shows that fragments are a significant cause of annular tears.
Where did these fragments come from?
Could free-floating fragments inside the disc represent a mechanical cause of back pain?
Could free-floating fragments breaking down inside the disc represent a chemical cause of back pain?
How Do You Know If You Have an Annular Tear?
Most patients find out they have an annular tear because they have persistent back pain and get an MRI scan that reads “annular tear or high intensity zone (HIZ).” The most accurate way to see an annular tear is to get a discogram followed by a CT scan that shows the size and extent of the tear by the dye seen. A provocative discogram with sedation can also tell if a tear is painful. Remember that annular tears are asymptomatic about 90% of the time.
Treatment Options for Annular Tear of the Disc
Time is on your side, but if your back pain hasn’t resolved after six months or keeps recurring, in my experience it will not go away with conservative care alone and deserves further evaluation.
Conservative Care: How Long Should I Give an Annular Tear to Heal?
1
Conservative care
The typical conservative care measures are physical therapy, exercise, stretching, and axial decompression — all considered conservative “non-operative” and worth pursuing at first. Although if the therapy aggravates the underlying condition or it won’t go away, there is a strong possibility you are dealing with an annular tear that is not going to heal with conservative therapy.
2
Pain management
Pain management may suggest injection of several things; however, a common treatment is an epidural, which may give relief for a few days up to a week, but then the pain will quickly return. This is also an indication that there is an annular tear that is not responding to pain management options, simply because the problem is on the inside of the disc, whereas the epidural injection is on the outside of the disc. Can PRP injections inside the disc be helpful? Can stem cell injections inside the disc be helpful for treating symptomatic annular tears?
3
Endoscopic discectomy Dr. Mork’s specialty
Endoscopic discectomy makes it possible to remove loose fragments from inside the disc and reduce the pressure and irritation that they are causing, as well as the chemical and mechanical issues. My research — in anticipation of a published paper — shows an average improvement of better than 60% (including all patients with a minimum of one year follow-up), which is a very reasonable way to approach this problem with a small surgical procedure and minimal complications.
4
Disc replacement or fusion
May be contemplated as a last resort.
Time is on your side. Proceed slowly, stage your treatment — annular tears can test your fortitude. But if conservative care has failed, don’t accept fusion as the only option.
Frequently Asked Questions About Annular Tears
Deep midline back pain, worst with sitting. Not sharp or radiating — a dull ache that waxes and wanes. It can be fine for weeks or even months and then just go out for no apparent reason, usually with some rest. That cycle will continue to repeat itself often for years and oftentimes gets more frequent with time.
Sometimes. Conservative care is always worth trying first. But in my experience, if the pain hasn’t resolved after six months — or keeps recurring — it will not go away with conservative care alone and deserves further evaluation.
After an annular tear forms, additional stress on the disc can cause the soft nuclear material to leak out from the interior — forming what is known as a herniated disc. An annular tear is the earlier injury. The pain mechanisms are different, which is why standard treatments for herniated discs often don’t resolve annular tear pain.
Yes. In my own research, annular tears were not reported on MRI in 50% of cases where a CT discogram clearly confirmed a tear. If your MRI is normal but you have persistent deep midline back pain, ask specifically about a discogram.
No. Conservative care first, always. When surgery is indicated, I perform an endoscopic discectomy — removing loose fragments from inside the disc to reduce pressure and irritation. My research shows an average improvement of better than 60%, with minimal complications.
Yes. Many patients come to me having already had procedures that didn’t resolve the pain — often because the annular tear was never identified as the source. Start with a phone consultation. I’ll review your history and imaging and tell you directly whether endoscopic surgery is an option.
Epidural injections may give relief for a few days up to a week, but then the pain will quickly return. This is because the problem is on the inside of the disc, whereas the epidural injection is on the outside of the disc. Temporary relief from an epidural that doesn’t last is itself an indication that there is an annular tear not responding to pain management.
PRP (platelet-rich plasma) injections into the disc are being explored as a treatment option for symptomatic annular tears. This is an evolving area and worth discussing during a consultation.
Stem cell injections into the disc are also being explored for treating symptomatic annular tears. This is an evolving area and worth discussing during a consultation.
Facet syndrome is commonly confused with annular tears. Both can cause deep midline back pain with a similar pattern — which is why a thorough history, physical exam, and appropriate imaging are all important in arriving at the correct diagnosis.
Intradiscal injections — including those described by Drs. Klein, Eek, and Mooney — place treatment directly inside the disc where the problem originates. PRP and stem cell injections inside the disc are also being evaluated as options for symptomatic annular tears.
The recovery is usually 2 months or more. The procedure is performed outpatient, and the average improvement across my patients — with a minimum of one year follow-up — is better than 60%.