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
The first thing to know is that, according to patient interviews, most annular tears don't hurt. This was discovered by interviewing people with annular tears found on their MRI scans. Approximately 90% of annular tears seen on an MRI do not correlate well with back pain. This is probably the main reason that people seen in an office with an annular tear are ignored. When we realize that 90% of annular tears don't hurt, we also understand that 10% can cause pain. When you combine this information with the knowledge that about 50% of annular tears are missed on the MRI, there can be many missed diagnoses.
Annular tears can become problematic in terms of how they present pain, but the most common are pain with sitting, especially in the car. This pain is described as deep in the midline and sometimes with a burning sensation. Pain can also radiate to the tailbone when sitting. Of course there are many other areas that the pain can be referred to, including joints and genitals, but the most common area is deep in the midline.
Yes, an annular tear is likely to heal on its own and that is why it's best to give a painful back plenty of time to heal. If you look at the literature, the time necessary to heal can be 12-18 months. This is primarily because of a very poor blood supply to the annulus and the fact that there is no way to hold the back still, it's always moving.
I've also observed that if deep midline back pain, aggravated by sitting, persists for more than 6 months, the likelihood of an annular tear is significant. I might also mention that if physical therapy usually aggravates the deep midline back pain, the possibility of an annular tear has to be considered.
By definition, a herniated disc has to have an annular tear for the fragment to herniate out of the disc. On the other hand, a tear of the annulus (covering of the disc) can occur without having a herniation.
Yes, you can have an annular tear even if the MRI report is read as normal. In a research project conducted in my office, I reviewed the MRI reports of 28 patients from all over the country with back pain. Part of my evaluation process is to perform a CT discogram and compare the findings with the MRI. My comparison showed that symptomatic annular tears clearly seen with the CT discogram were not reported on the MRI 50% of the time. For this reason, I don't think MRI's, by themselves, are an ideal method to evaluate chronic low back pain.
An annular tear does not always require surgery. I think the minimum time to allow healing of an annular tear is 6 months. If a tear is becoming less symptomatic with time, additional time should be allowed for conservative treatment. There should be no impatience when considering surgery to treat an annular tear. The key words for treating a symptomatic annular tear is time (how long has the tear been present) and how much the pain or "giving way" is impacting one's life.
Yes, just because you've had previous spine surgery, it doesn't mean that your current pain is related in any way. I find it best to listen to the history, review the MRI and try to come up with a good working diagnosis to evaluate your options.
Epidural injections can give back or leg pain relief from a symptomatic annular tear, but the pain relief is usually short lived. I believe the reason for this is that the back and leg pain caused by an annular tear results from toxic chemicals leaking out of the disc and into the epidural space. The epidural steroid injection is also injected into the epidural space and can temporarily dilute or disinflame the toxic chemicals leaking out of the disc, but it doesn't work for very long because the toxic chemicals continue to leak out of the disc. In other words, the epidural injection is on the "wrong" side of the disc, the annular tear problem with the disc is on the inside of the disc, not the outside of the disc which is in contact with the epidural space where epidural injections are placed.
PRP or Platelet Rich Plasma injections use a centrifuge to separate red blood cells from plasma which has a higher concentration of platelets and growth factors to stimulate soft tissue healing. There is a lot of interesting research going on in the field of biologics for the treatment of painful conditions including low back pain, which is great, but I also like things to make sense too. I know that some research papers note improvement at 2 and 6 months post injection, but what about after that?
In my assessment of disc pain caused by annular tears, there are two things that must be taken into account. First, is the fact that a blood supply is necessary for healing to occur and the inside of a lumbar disc doesn't have a blood supply, so I'm not sure how a PRP injection into the disc is supposed to work without a blood supply. How is a platelet cell supposed to survive without a blood supply and minimal oxygen in a relatively hostile environment?
Secondly, I believe a lot of the problems that result from annular tears really start with the free floating fragments of cartilage that are dead and there is nothing good about a disc filled with dead tissue fragments with no blood supply, low oxygen, and a low pH (high acid). It is my opinion that these dead fragments need to be removed before any meaningful healing can occur, perhaps once the environment is improved PRP could be of great benefit.
I would say no, based on my experience and a paper I published in 2006.
There is a lot of interesting research going on in the field of biologics and stem cells for the treatment of painful conditions including low back pain. The paper I published in 2006 was the fastest paper that I ever had published because it reported a 100% failure to relieve back pain with stem cell injection. I realize that there are many different types of stem cells available now and things may have changed somewhat, but there are still 2 major problems associated with injecting any living tissue into a degenerative disc with annular tears with the goal of long term pain relief.
In my assessment of disc pain caused by annular tears, there are elements that must be taken into account. First, is the fact that a blood supply is necessary for cell growth and healing to occur, and the inside of a lumbar disc doesn't have a blood supply, so I'm not sure how a stem cell injection into the disc can overcome this fact. Perhaps the stem cells could follow the annular tears and tracts to the periphery of the disc where the annular tears are located and help with the repair and healing process with a marginal blood supply. So even if the annular tears could be healed, stem cell injection probably doesn't address the cause of the annular tears or the hostile environment inside of the disc.
Secondly, what is the cause of the annular tears and hostile environment inside of the disc? My work suggests that annular tears are created by small free floating fragments of cartilage (disc) that have broken away from their nutritional supply. These small fragments can't get out of the disc (larger fragments can herniate), and migrate to the periphery to the annulus under the weight of the body. The migration causes tearing. These small fragments cannot be seen by any current imaging techniques and were discovered with the endoscope during endoscopic spine surgery. These trapped fragments will continue to break down and release lactic acid and other inflammatory substances, unless removed. If the dead and decaying fragments are not removed, the environment just continues to deteriorate with low oxygen tension, and a low pH (high acid) environment.
It is my opinion that these decayed fragments need to be removed before any meaningful healing can occur, perhaps once the disc environment is improved, stem cells could be of significant benefit.
There is a chemical injection available for painful discs with annular tears that was published many years ago.
Biochemical injection treatment for discogenic low back pain: a pilot study☆
Author links open overlay panel
Robert G Klein MD a, Björn C.J Eek MD a, Conor W O'Neill MD b, Caren Elin DC c, Vert Mooney MD d, Richard R Derby MD b The Spine JournalVolume 3, Issue 3, May–June 2003, Pages 220-226
A Randomized Double-Blind Trial of Dextrose-Glycerine-Phenol Injections for Chronic, Low Back Pain
Robert G. Klein, Bjorn C. Eek, W. Bradford DeLong, Vert Mooney Journal of Spinal Disorders 6(1):p 23-33, February 1993.
This injection is a very interesting approach to discogenic back pain that is very safe with minimal complications, pretty effective and can last a long time. In the publication, the proliferant injection group achieved a 50% or greater diminution in pain or disability scores at 6 months from the injection. The injection's main component is a 50% Dextrose solution which is hypertonic and diluted to some extent. It's not clear why it works as well as it does, but I suspect that the hypertonic solution might render the small sensory (pain) nerves inoperative, so they can't conduct any pain signals.
I have used this injection hundreds of times and found that about 50% of people injected will have at least a 45-50% reduction of pain by 6 months and that the relief can last years. The main reason I use it is if people have a disc space that is too narrow to get an endoscope in the disc space or if they have had the endoscopic disc surgery and still experience back pain.
This is an interesting question because there is no simple "one size fits all" answer. The recovery can last from 8 weeks on the short side to 9 months on the long side and it is not possible to tell who will have a short or long recovery. The main problem is that it's common to have a significant reduction of pre-op back pain about 2 weeks after the surgery, and most people are tempted to "test the work" and get too active and the pain can return, so not a good idea.
I usually tell patients that the recovery will occur at one of three time frames: 2-3 months, 6 months, and sometimes the recovery will last to 9 months. Lifting restrictions are 10-15 pounds and walking is the main activity recommended. Changing positions (sitting, standing, laying down and walking) is recommended and if sitting is a big part of your work day, I suggest a standing desk.