Although the literature is filled with information about the prevalence and incidence of back pain in general, there is less information about chronic back pain, partly because of a lack of agreement about definition.
Chronic back pain is sometimes defined as back pain that lasts for longer than 7-12 weeks. Others define it as pain that lasts beyond the expected period of healing, and acknowledge that chronic pain may not have well-defined underlying pathological causes. Others classify frequently recurring back pain as chronic pain since it intermittently affects an individual over a long period. Most national insurance and industrial sources of data include only those individuals in whom symptoms result in loss of days at work or other disability. Thus, even less is known about the epidemiology of chronic low-back pain with no associated work disability or compensation. Chronic low-back pain has also become a diagnosis of convenience for many people who are actually disabled for socioeconomic, work-related, or psychological reasons. In fact, some people argue that chronic disability in back pain is primarily related to a psychosocial dysfunction. Because the validity and reliability of some of the existing data are uncertain, caution is needed in an assessment of the information on this type of pain 1).
The socioeconomic toll of lumbar disc disorders is enormous, underscoring the critical importance of understanding the pathophysiology behind the degenerative process.
Pain catastrophizing, appraisals of pain control, styles of coping, and social support have been suggested to affect functioning in patients with low back pain.
Back pain characteristics, depressive mood, disability, and beliefs about personal control of pain are related to chronic LBP coping styles. Most of the variables related to advancement of degenerative changes were not associated with coping efforts 4).
The association between chronic low back pain and morphologic, structural changes of the lumbar paravertebral muscles has been widely acknowledged.
Mechanical alterations of the spine, which can cause chronic low back pain (LBP), are a frequent indication for spinal fusion.
Rarely can an anatomic diagnosis be made in patients with chronic LBP ≥ 3 months duration 5).
Patients with chronic pain syndromes (CPS) refer to their problems with affective or emotional terms with a higher frequency than those with acute pain. 6).
After 3 months, only ≈ 5% of patients with LBP will continue to have persistent symptoms. A structural diagnosis is possible in only ≈ 50% of these patients. These patients account for 85% of the cost in lost work and compensation 7).
The amount of time that a patient has been out of work due to low back problems is related to the chances of the patient getting back to work.
Differential diagnosis includes
1. degenerative conditions
a) degenerative spondylolisthesis
b) spinal stenosis(affecting the spinal canal)
c) lateral recess syndrome
a) ankylosing spondylitis:look for erosive changes adjacent to SI joint and positive test for HLA- B27 antigen
b) Paget’s disease of the spine: vertebral involvement is very common in a patients with Paget’s disease
3. osteitis condensans ilii: increased density in ilium, usually asymptomatic (incidental) finding. Occasionally may produce low back pain or tenderness. Usually found in women who have been pregnant
4. psychological overlay: including secondary gain (financial, emotional…)
28 patients with low back pain, with a duration > 6 months and a 50% pain reduction on the numeric analog scale (NAS) after a diagnostic block. All patients received endoscopic facet joint denervation of three facets on the left and right side using only one incision on each side with an exploration of the surrounding tissue. Telephone interviews were conducted with all patients. The outcome was determined with Odom's criteria, percentage reduction NAS, subjective assessment of the patient, and duration of the effect.
According to Odom's criteria, 68% of the patients showed “acceptable” to “excellent” results and confirmed that denervation helped them manage their daily lives better. The average pain reduction in the responder group was 47% with an average duration of 7.8 months.
In this retrospective study, Woiciechowsky and Richter from the Vivantes-Humboldt-Klinikum, Spine Clinic, Spine Center Berlin, Charité Medical Faculty Berlin, demonstrated the practicability and effectiveness of the endoscopic facet joint denervation procedure in the treatment of chronic low back pain using only one incision for three facets. Further studies should investigate if this procedure is more effective than percutaneous radiofrequency denervation 8).
Fourteen patients with CLBP, greater than 6 months, unresponsive to at least 4 months of conservative care were enrolled. All patients were treated successfully following screening using MRI findings of Modic type I or II changes and positive confirmatory provocative discography to determine the affected levels. All patients underwent ablation of the basivertebral nerve (BVN) using 1414 nm Nd:YAG laser-assisted energy guided in a transforaminal epiduroscopic approach. Macnab's criteria and visual analog scale (VAS) score were collected retrospectively at each follow-up interval.
The mean age was 46 ± 9.95 years. The mean symptoms duration was 21.21 ± 21.87 months. The mean follow-up was 15.3 ± 2.67 months. The preoperative VAS score of 7.79 ± 0.97 changed to 1.92 ± 1.38, postoperatively (P < 0.01). As per Macnab's criteria, seven patients (50%) had excellent, six patients (42.85%) had good, and one patient (7.14%) had fair outcomes.
The transforaminal epiduroscopic basivertebral nerve laser ablation (TEBLA) appears to be a promising option in carefully selected patients with CLBP associated with the Modic changes 9).