Exploring the Intervertebral Disc
Sitting between the vertebrae, intervertebral discs serve as shock absorbers, helping enhance fluidity and strength of spinal motion, and dispersion of axial and torsional forces. These discs can also play a role in back pain in the setting of an acute herniation. In this case, compression of an exiting nerve root or the collection of nerve roots contained within the dura from bulging disc material will result in lower extremity radicular pain—the classic sciatica. A large central disc herniation can present with predominantly low back pain in the setting of minimal or no lower extremity symptoms. On the other hand, a more lateral disc herniation will produce more leg pain or radicular pain.
Examining the Impact of LBP
There are approximately 19 million office visits each year for LBP (for a total cost of billion in office visits alone). This represents 2% of all office visits, exceeded only in quantity by routine examinations, hypertension and diabetes.
The results from The National Health Care Survey published by the U.S. Department of Health and Human Services show that spinal problems are among the top primary diagnoses during ambulatory care visits. The prevalence has been increasing over time, which correlates with an increase in opioid use, and escalating utilization of interventional pain management techniques and surgical procedures. Low back pain is also a common cause of lost productivity and workdays. Five percent of American workers miss at least one day annually due to LBP, and the most common occupational injury, in most states, is to the spine.
Most physicians examine individuals with intervertebral disc herniation because they are experiencing either leg or low back pain, with or without a variable degree of motor or sensory loss. Pain, in this case, is caused by not only the mechanical effect of the herniated material on the nerve root, but also from chemical and autoimmune reactions causing the root inflammation.
Evaluating LBP or LBP-related leg pain
There is an urgent need to develop and rigorously evaluate the current screening approaches for individuals with LBP or LBP-related leg pain from intervertebral disc disease. Approximately 54–80% of the adult population will experience LBP at least once in their lifetime. The majority of patients will experience relief of their symptoms; however, a subset of the population may advance to a diagnosis of chronic low back pain. The prevalence of chronic LBP is 2–40% and varies between etiologies and age groups.
Evolving from Excessive Diagnostic Delays to Effective Screening
Wait times for patients with LBP and LBP–related leg pain referred for assessment are excessive, and many of these referred individuals may not be appropriate surgical candidates.
Dr. Julian Naranjo, a pain specialist, says, “The current protocols for diagnosis and treatment of low back pain and lumbar radicular pain are not designed for early diagnosis and treatment. So far, the focus has been on cost containment at the expense of early diagnosis and treatment. This could be due to the expensive nature of current therapies and the associated risk for chronic pain and disability.”
One promising approach to address the excessive wait times is utilizing primary care physicians and non-physician clinicians (NPCs) to effectively screen waiting list patients to improve the timeliness and relevant acquisition of individual history and to perform initial clinical screening examinations. Researchers have already explored the role of NPCs, such as physiotherapists, chiropractors, and nurse practitioners, as screeners of these spinal “waiting list” patients.
“Intervertebral disc disease is a serious issue because left uncorrected it may lead to degenerative disc disease, which, in and of itself, leads to many secondary conditions,” said Mary Rodda, D.C., of Chiropractic Works in New York. “Chiropractors are specialized in the structure of the human frame and structural alignment of the spine—we are often making the correct diagnosis and formulate an appropriate therapeutic plan with these patients.”
When assessing an individual with low back and/or leg symptoms in a primary care setting, four simple questions must be answered by the primary care physician or the NPC:
If ‘yes’ is the answer to any of the above, referral to either the emergency department or a specialist clinic is the obvious next step.
If ‘no’ is the answer, then the only issue to be dealt with is pain.
While medical history and clinical examination remain the cornerstones of spinal assessment in any setting, a full neurological examination will generally detect all serious deficits.
It is important for the NPC to screen and identify the pain mechanism in patients with leg pain to have a better understanding of the patient’s individual disorder and inform management strategies. Consensus among national and international guidelines for the management of LBP recommends that diagnostic triage should be performed. Patients with LBP should be classified into 1 of 3 diagnostic groups—nonspecific LBP, serious pathology (e.g., tumor, infection, fracture), or radicular syndrome. Radicular syndrome (i.e., sciatica, radiculopathy, or nerve root pain) is characterized by radiating leg pain and paresthesia as well as clinical signs of neurologic impairment, and in approximately 90% of cases it is caused by a herniated disk with nerve root compression.
People who are obese or those having jobs requiring prolonged sitting, repetitive heavy lifting, and twisting or vibration exposure will be more prone to disc degeneration and herniation. All these factors, along with cigarette smoking and intense physical activity, can accelerate disc degeneration beyond what occurs with normal aging and maturation.
Leg pain remains a reliable prognostic factor concerning the eventuality of lower back surgery, but there are conflicting results regarding the association between self-reported leg pain severity in the initial stage of sciatica and the patients’ final outcome.
Dramatic and rapid change in leg pain severity may be one reason for the conflicting results found in similar studies regarding the association between baseline (initial) sciatic pain severity and sciatic pain chronicity. Recent reviews of other prognostic factors conclude that psychological, social, and economic factors are also important predictors for chronic LBP.
“Low back pain and associated leg/radicular pain has been one of the unresolved puzzles of modern medicine, as some therapeutic techniques fail to produce significant improvement of pain and function. This paradigm is one of the reasons new therapies are being sought,” says Dr. Naranjo. “The first basic principle in medicine is not to harm. Therefore, the ideal therapy for back pain and radicular pain should be noninvasive or as minimally invasive as possible, keeping the body homeostasis and or helping to recover it, facilitating functional improvement and reintegration of the patient to a normal productive life.”
Comprehensive multidisciplinary assessment for intervertebral disc disease followed by multiple methods of treatment yields the best results.
References
Abd-Elsayed A, ed. Pain: A Review Guide. Springer International Publishing: Imprint: Springer, 2019.
Ashworth J, Konstantinou K, Dunn KM. Prognostic factors in nonsurgically treated sciatica: a systematic review. BMC Musculoskelet Disord. 2011;12:208.
Bishop P, Brunarski D, Fisher C. The multidisciplinary interexaminer reliability of patient screening assessments in a hospital based spine program: A Pilot Study. Abstract presented at: 10th Annual Scientific Conference of the Canadian Spine Society; March 10–13, 2010; Lake Louise, Alberta, Canada.
DePalma MJ, Ketchum JM, Saullo T. What is the source of chronic low back pain and does age play a role? Pain Med. 2011;12:224–33.
Dunlop B, McLaughlin L, Goldsmith C. Non-Physician Triage in Patients with Back Pain, Sciatica and Spinal Stenosis. Abstract presented at: 10th Annual Scientific Conference of the Canadian Spine Society; March 10-13, 2010; Lake Louise, Alberta, Canada.
Kalichman L, Cole R, Kim DH, Li L, Suri P, Guermazi A, et al. Spinal stenosis prevalence and association with symptoms: the Framingham study. Spine J. 2009;9:545–50.
Koes BW, van Tulder M, Lin CW, Macedo LG, McAuley J, Maher C. An updated overview of clinical guidelines for the management of non-specific low back pain in primary care. Eur Spine J. 2010;9:2075–94.
Larochelle MR, Zhang F, Ross-Degnan D, Wharam JF. Trends in opioid prescribing and co-prescribing of sedative hypnotics for acute and chronic musculoskeletal pain: 2001–2010. Pharmacoepidemiol Drug Saf. 2015;24:885–92.
Manchikanti L, Benyamin RM, Helm S, Hirsch JA. Evidence-based medicine, systematic reviews, and guidelines in interventional pain management: part 3: systematic reviews and meta-analyses of randomized trials. Pain Physician. 2009;12:35–72.
Martin BI, Deyo RA, Mirza SK, Turner HA, Comstock BA, Hollingworth W, et al. Expenditures and health status among adults with back and neck problems. Journal of the American Medical Association. 2008;299:656–664.
Peul WC, Brand R, Thomeer RT, et al. Improving prediction of ‘‘inevitable’’ surgery during non-surgical treatment of sciatica. Pain. 2008;138:571–6.
Poynton, Ashley. “Low Back Pain and Sciatica – a Surgeon's Perspective.” Irish Medical Times, vol. 51, no. 26, 2017, p. 40.
Sarro A, Rampersaud YR, Lewis S. Nurse practitioner-led surgical spine consultation clinic. J Adv Nurs. 2010; 66: 2671–6.
Schappert SM, Burt CW. Ambulatory care visits to physician offices, hospital outpatient departments, and emergency departments: United States, 2001–02. Vital Health Stat 13. 2006;159:1–66.
Valat JP, Genevay S, Marty M, Rozenberg S, Koes B. Sciatica. Best Pract Res Clin Rheumatol 2010;24:241–52.
Verwoerd AJH, Luijsterburg PAJ, Lin C-WC, et al. Systematic review of prognostic factors predicting outcome in non-surgically treated patients with sciatica. Eur J Pain2013;17:1126–37.
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