It’s not often that a new research finding clinically reveals itself so quickly, but in this case it did. In the Cox Research Pearls (published monthly), a radiological finding called the nerve root sedimentation sign was discussed. This sign indicates severe lumbar spinal stenosis.(1)
What is this sign? “A positive sedimentation sign was defined as the absence of nerve root sedimentation in at least one axial MRI scan, at a level above or below, disregarding the location of the scan within the level and its proximity to the maximal stenosis. It is not the only case where a sign refers to the absence of a finding (i.e., the positive Thompson test in which the absence of plantar flexion helps to confirm the diagnosis of an Achilles tendon rupture). As a rule, nerve roots normally sediment, due to gravity, to the dorsal part of the dural sac, which is defined as negative sedimentation sign. The only exception is the two nerve roots leaving the dural sac one segmental level below the stenosis. If there are nerve roots in the ventral part of the dural sac except for the ones exiting the dural sac, the sedimentation sign is positive. By this method, no intermediate or indeterminate results of the sedimentation sign are to be expected. The sedimentation sign was measured at a level above or below the maximal stenosis because, at the level of the stenosis, nerve roots lie tightly packed in the dural sac and therefore cannot be identified and judged adequately.”(2) This patient came to the office just as this research pearl revealed itself and made an exciting clinical practice day, as well as a strong indicator of the correct diagnosis.
This 59-year-old white male came to the office with chief complaints of lumbar spine and bilateral leg pain, numbness and weakness to the feet. He had a long history of back and leg pain that began in his 30s. He stated that in his occupation he had to stand and walk on concrete for many hours. His symptoms progressed to severe back and sciatic pain. He had attempted many conservative treatments prior to surgery: physical therapy, chiropractic, back exercises, swimming, massage, acupuncture, traction, three epidurals and oral steroids. None offered substantial benefit. Because of worsening symptoms, in 2005 he had L4 spinal laminectomy. The surgery was a success and gave him relief of the low-back and leg pain. Unfortunately, the pain in the back and legs returned in 2009-2010, and he sought another neurosurgical consult. The neurosurgeon told him that the surgery “would not be a good idea.” He was told to live with the pain as well as he could. He did so until a severe bout of bilateral leg and spine pain lasting for one week caused him to follow his sons’ suggestion to consult with me.
The patient presented in pain with a 15-degree flexed antalgic posture while standing. Sitting and recumbent postures were generally the most comfortable. The deep tendon reflexes were 1/2 at the patella and Achilles tendons. Muscle strengths were globally +4/5 in the lower extremities. Dermatomal evaluation of the lower extremities showed patchy hypesthesia in the L3-S1 dermatomes with the L5 most affected. Valsalva sign was negative. Pain on palpation was evident from L3 through S1 bilaterally in the paraspinal musculature and caudally into the gluteals, sciatic notch and especially tender at the popliteal fossa and abductor muscles. Range of motion of the lumbar spine was as follows: extension 10° with pain and bilateral radicular symptoms to the feet. Flexion 60° with lumbosacral discomfort described as aching and stiff. Lateral flexion 20° bilaterally with the same symptoms. Rotation is limited to 15° bilaterally with no pain. Bilateral SLRs were positive for mild radicular pain at 40° with very tight hamstrings. Kemp’s sign was positive for radicular and low-back pain bilaterally. Sacroiliac testing was negative. The patient was unable to squat to stand without balance and arm assist for strength. This patient could perform Romberg’s test and heel/toe walk. However, balance was difficult.
Treatment and Outcome
The patient was given electrical muscle stimulation (EMS) with a hot pack to the lumbar spine and buttocks on Nov. 4, 2014. Due to the seriousness of his symptoms and the potential for iatrogenic response, no manipulation was given, and a referral for MRI was provided. The patient returned with the MRI results on Nov. 12, 2014. We reviewed the images together, and a full report of findings was given to include the potential for a worsening of the condition with care. I described the cauda equina syndrome symptoms and explained the pros and cons of several alternative therapies, both conservative and surgical. The patient was told that the goal of initial treatment was to achieve 50 percent overall improvement within four weeks of care. He stated he understood and felt he could afford twice-weekly visits and wished to begin care. He was treated with Cox® F/D Protocol 1 (3,4), bi-phasic EMS, a hot pack and was given complete home care instructions to include the Cox® exercises, a Discat Plus supplement, anti-inflammatory nutraceuticals, etc. He was treated for four weeks with twice-a-week visits.
A re-exam was done at the end of the four weeks with the following findings: The patient no longer had an antalgic posture while standing. The deep tendon reflexes were unchanged. Muscle strengths were unchanged at +4/5 in the lower extremities. Dermatomal evaluation of the lower extremities showed less profound hypesthesia, with the L5 still the most affected. Pain on palpation was reduced in the paraspinal musculature caudally into the gluteals, sciatic notch, popliteal fossa and abductor muscles. Range of motion of the lumbar spine was as follows: extension 30° with low-back pain only, flexion 80°, lateral flexion 20° and rotation 25° bilaterally with no pain. Bilateral SLRs were negative for radicular pain yet the tight hamstrings were painful when challenged muscularly. Kemp’s sign was positive for low-back pain bilaterally. The patient was asked to stretch the hamstrings more diligently.
On this first re-exam, he stated that he was 50 percent improved. In fact, he said he felt that much improved after the third treatment. He was then reduced in treatment frequency and treated with Cox® Protocol II (3,4) once per week for six weeks. This was followed by a re-exam with essentially the same findings as the first. The patient stated that he was then 85 percent overall improved. His legs were pain free most of the time, and the low back was more manageable. At this point he asked about inversion therapy at home. I suggested he use it at a limited 40° beyond horizontal plane for short durations (5 minutes) with caution. He continued to be seen for care and tapered down to maintenance treatment. He was laid off work for quite a while and received a call in January 2015 to return. He decided that he can return to work now that the pain is under control. I have suggested he be fitted for custom-made orthotics to reduce the irritation to the spine, especially as he works standing on concrete all day.
For interest’s sake I have included my finding of a positive sedimentation sign on MRI axial images (see Figures 10 and 11).
This case held several positive findings and results. First and foremost was the rapidity with which the patient responded to the Cox® treatment in spite of the severity of the patient history, clinical findings and diagnostic imaging. Fifty percent improvement in three visits was astounding. The sedimentation sign was a nice confirmation of severe stenosis. This case highlights the valuable tools we possess as doctors of chiropractic to alleviate even the most challenging stenosis cases and help our patients regain their quality of life.
The experience of reading new research and incorporating new research findings into clinical practice raises our confidence and our patients’ esteem. Applying research to clinical practice elevates us all.
Zhang L, Chen R, Xie P, Zhang W, Yang Y, Rong L: Diagnostic Value Of The Nerve Root Sedimentation Sign, A Radiological Sign Using Magnetic Resonance Imaging, For Detecting Lumbar Spinal Stenosis: A Meta-Analysis. Skeletal Radiol 2014 [Epub Ahead of Print].
Dawood OM, Hassan TA, Mohey N: The MRI Finding of the nerve root sedimentation sign: Its clinical validity and operative relativity for patients with lumbar spine stenosis. The Egyptian J of Radiology and Nuclear Med 2014; 45(1):203-209.
Cox JM: Low Back Pain: Mechanism, Diagnosis, Treatment, 7th edition. Baltimore. Lippincott Williams & Wilkins, 2011, Chapter 8, pgs. 364-365.
Julie Cox-Cid is coordinator for Cox® Technic and is available at 800-441-5571, firstname.lastname@example.org; www.coxtechnic.com. The featured case report is by Lee Hazen, DC, a Cox® Technic certified physician practicing in Temecula, Calif.
Dr. Kelli Pearson, DC, DABCO, FICC, ACA Governor District 1, completed a certification course on Cox Technic with Dr. Cox and gives it a HUGE thumbs up!