LBP is one of the most common pa in complaint and usually one of the hardest syndromes to treat. Interventional pain management offers an opportunity to assist in the diagnosis and management of back pain.
Low back pain (LBP) is one of the most common pain complaints. It is the second most common pain disorder after headache. At least 60-90 per cent of adults will have LBP at some time during their lifetime. Acute low back pain is the fifth most common reason for all physician visits. Although symptoms are usually acute and self-limited, low back pain often recurs. It becomes more difficult to control and treat when it becomes a chronic disease. Low back pain is one of the most commonly cited problems for lost work time in industry and disability in patients of age less than 45 years.
Studies have generally shown the following factors to be associated with the development of back pain: jobs requiring heavy lifting, use of jackhammers and machine tools, operation of motor vehicles, cigarette smoking, anxiety, depression, stressful occupations, and women with multiple pregnancies, scoliosis and obesity.
Identifying a clear etiology of LBP can be very complicated and challenging. Knowing the complexity of the structure of the spine and biomechanics of the spinal segments is very important in understanding the pain generator in the low back. Multiple studies have shown that causes of LBP correlate with <15 per cent with underlying nerve root compromise, 85 per cent have non-neurogenic back pain and the remainder assumed to have musculoligamental injury or degenerative changes. Some of these pathologies include but not limited to: muscle strain, ligamental injury, facet disease, synovial disease or cyst, compression fracture, pars defect, sacroiliac joint dysfunction, internal disc disruption as well as primary neoplasm or metastatic disease.
History and Physical Examination remain the most important initial work up in evaluating LBP. The history should include the patient’s age, past medical and surgical history and any history of trauma. The presence of constitutional symptoms, night pain, bone pain or morning stiffness, claudication, numbness, tingling, weakness, radiculopathy, and bowel or bladder dysfunction should be noted. The onset of pain, its location, radiation, characteristics, and severity should be assessed. A detailed neurologic evaluation should be performed. Patients with low back pain should be screened for the possibility of potentially serious conditions including possible fracture, tumor, infection, or cauda equina syndrome. Frequently, there are well described “red flags” which distinguish these serious conditions from the much more frequent “benign” causes (degenerative disc disease, disc herniation, and spondylolisthesis) of low back pain.
Psychosocial Evaluation and Screening for non-physical factors is critical in the management of back pain like any other pain syndrome. Psychological, occupational and socioeconomic factors can complicate both assessment and treatment.
Imaging studies: MRI today has become the modality of choice in the evaluation of spinal degenerative disease. MRI is superior even to CT with contrast in the distinction of bone, disc, ligaments, nerves, thecal sac, and spinal cord. It is the test of choice for the diagnostic imaging of neurologic structures related to low back pain. However, MRI can identify abnormalities in asymptomatic persons. Therefore, the correlation between patient symptoms, history and exam findings and the imaging results is very important in targeting the pain generator in the low back and reaching a comprehensive diagnosis and treatment plan.
Short period of rest, analgesics, retuning to function and normal activity as soon as possible and then an exercise program and physical therapy to minimize reoccurrence. In chronic LBP, the multidisciplinary biopsychosocial rehabilitation treatments with functional restoration have been shown to improve pain and function. Nonsteroidal anti-inflammatory drugs (NSAIDs) are moderately effective for the short-term symptomatic relief of patients with low back pain. There does not seem to be a specific type of nonsteroidal antiinflammatory drug that is clearly more effective than others.
If no medical contraindications are present, a two- to four-week course of an anti-inflammatory agent is suggested. Gastrointestinal prophylaxis might be necessary with the older types of NSAIDs for patients who are at risk for peptic ulcer disease. The selective cyclo-oxygenase¬2 inhibitors have fewer gastrointestinal side effects, but they still should be used with caution in patients who are at risk for peptic ulcer or kidney disease. The short-term use of a narcotic may be considered for the relief of acute pain. The need for prolonged narcotic therapy should prompt a reevaluation of the etiology of a patient's back pain. The use of muscle relaxants has been shown to have a significant effect in reducing back pain, muscle tension and increased mobility after one and two weeks. All these medication can have significant adverse effects even after a short course and should be used cautiously.
Interventional pain management is defined as the discipline of medicine devoted to the diagnosis and treatment of pain related disorders principally with the application of interventional techniques in managing sub acute, chronic, persistent, and intractable pain, independently or in conjunction with other modalities of treatment. Interventional pain management techniques are defined as minimally invasive procedures including, percutaneous precision needle placement, with placement of drugs in targeted areas as well as nerve block or ablation of targeted nerves; for the diagnosis and management of chronic pain.
One of the most common injections used for LBP is Epidural Steroid Injection (ESI). This injection can be performed via an interlaminar or transforaminal approach. The typical patient has degenerative disc disease with or without radiculopathy symptoms. Risks associated with the procedure are minimal if the physician performs adequate screening and follows appropriate selection criteria. Complications include but not limited to bleeding, infection, and possible post dural puncture headache. Multiple studies have shown that the needle can be positioned inappropriately when the procedure is performed without image guidance” blindly”. In 30 to 52% of the cases, the needle misses the epidural space. Using fluoroscopy confirms the accurate placement of the needle, the distribution of medication within the epidural space, and minimizes any risk of possible complications.
Using epidural steroid injections in appropriate patients is recommended. If they fail to improve after a single injection, a trial of three injections (old practice) is probably not indicated. Reevaluating the LBP etiology, considering different injections approach or a diagnostic nerve block would be more suitable in those cases. Multiple studies have shown that predictors of good result with epidural steroid injection usually correlate with: advanced educational background, primary diagnosis of radiculopathy and pain duration of < 6 months. Poor results often correlate with: constant pain, sleep disruption and unemployed due to pain.
Other injections which are considered diagnostic as well as therapeutic include but not limited to intra-articulr injection of the facet joins or sacroiliac joints as well as selective median branch blocks to those joints. Discography which is intradiscal injection of contrast material is considered when discogenic pain is suspected. This procedure is a diagnostic injection.
Recent advanced techniques in interventional approach to LBP introduced minimally invasive intradiscal procedures like Neucleoplasty and Intradiscal Electrothermal Annuloplasty (IDET). Those intervention offer percutaneous procedures to treat disc pathologies and avoid invasive surgical options to treat chronic LBP.
LBP is one of the most common pain complaint and usually one of the hardest syndromes to treat. Interventional pain management offers an opportunity to assist in the diagnosis and management of back pain. By offering a thorough assessment of the various possible causes of pain, treatment planning can be tailored to patients’ pathophysiology. These procedures also offer the opportunity to manage patients with minimally invasive procedures. Interventional pain treatments are generally better tolerated than surgery, as they are less invasive, less painful and can usually be performed outpatient.
Oftenspecialist in the field use different terminology to describe disc diseases. This can be very confusing to the patients and to some healthcare providers. The North American Spine Society (NASS) recommended detailed definitions of lumbar disc pathology to standardize terminology among experts in the field. Some of the common descriptions of disc diseases are:
Degenerated disc: Changes in a disc characterized by dessication, fibrosis and cleft formation in the nucleus, fissuring and mucinous degeneration of the annulus, defects and sclerosis of the endplates, and/or osteophytes at the vertebral apophysis.
Displaced disc: A disc in which disc material is beyond the outer edges of the vertebral body ring apophysis (exclusive of osteophytes) of the craniad and caudad vertebrae, or as in case of intravertebral herniation, penetrated through the vertebral body endplate. The term includes, but is not limited to, disc herniation and disc migration.
Herniated disc: Localised displacement of disc material beyond the normal margins of the intervertebral disc space. Non-standard definition: any displacement of disc tissue beyond the disc space. Disc material may include nucleus, cartilage, fragmented apophyseal bone, or fragmented anular tissue.
Schmorl’s Node: Intravertebral herniation: A disc in which a portion of the disc is displaced through the endplate into the centrum of the vertebral body.
Spondylitis: inflammatory disease of the spine, other than degenerative disease. Spondylitis usually refers to noninfectious inflammatory spondyloarthropathies.
Spondylosis: Spondylosis deformans, for which spondylosis is a shortened form. Non-
Standard definition: any degenerative changes of the spine that include osteophytic enlargement of apophyseal bone.
Spondylolisthesis: anterior displacement of one vertebra, typically L5, over the one beneath it.