Interventional Approach To Low Back Pain Pradeep Chopra, MD  Th i s is t h e b r i e f t r e a t i s e o n t h e articular processes. These articulate with endplate. These are two layers of cartilage interventional approach to managing spi- the vertebrae above and below to form which from the upper and lower aspects nal pain with special reference to low back facet joints. As with joints elsewhere in of the disk. pain. This article discusses predominantly the body, the facet joints are lined with low back pain but the same principles ap- a cartilage and surrounded by a capsule. The Sacroiliac Joint ply to neck pain and thoracic pain, with The facet joints are prone to age-related The pelvic girdle is formed by the some variation. I also want to stress that arthritis, arthrosis (age-related degenera- iliac bones and the sacrum. The sacrum the treatment of spinal pain, as in most tive changes) and injury. forms a joint on each side with the iliac chronic pain conditions, must have a When the spine is viewed from the bones called the sacroiliac joints. It does multidisciplinary approach. There is no side, one can see the intervertebral foram- not exhibit active movement but does one single modality that is most effective ina, an oval opening through which the move passively. Its chief role is to act for treating spinal pain. In most cases, a spinal nerves exit the spinal canal. These as a stress relieving joint. As with joints few of these modalities have to be done are formed by the pedicles of the verte- elsewhere, the sacroiliac joint is also simultaneously. For example, physical brae above and below and are bordered prone to arthritic changes and injury. therapy in conjunction with interven- by the disc anteriorly and the facet joint The sacroiliac joint is a very common site tional pain management or weight loss, posteriorly. The height (size) of the fora- for low back pain, especially in women. smoking cessation in conjunction with men is thus determined by the height of Sacroilitis is recognized as part of the core strengthening exercises. the intervertebral disc but, may also be spectrum of ankylosing spondylitis and According to the American Soci- narrowed by hypertrophy or overgrowth other spondylarthropathies, psoriatic ety of Interventional Pain Physicians of the facet joint with arthritis. Narrow- arthritis and arthritis related to inflam- (ASIPP), interventional pain manage- ing of the intervertebral foramen is called matory bowel disease such as Ulcerative ment is “a discipline of medicine devoted foraminal stenosis and, when there is Colitis and Crohn’s disease. The more to the diagnosis and treatment of pain associated impingement of the nerves, it common condition is Sacroiliac Joint related disorders.” For patients with back may result in radiating pain down the leg Dysfunction often attributed to hyper- pain, interventional pain management or “radiculopathy.” mobility or hypomobility of the joint. It techniques are especially useful both from may also be seen in some patients who a diagnostic as well as a therapeutic point Inflammation of have a long-standing history of lumbar of view. Interventional pain physicians fusion. These patients usually present have a wide array of treatment modalities the nerves has with lower back pain, gluteal pain and that they can use to manage spinal pain. been proposed hip joint pain. The pain radiates into the In order to understand treatment of groin and lower extremities. The pain in- low back pain one has to understand the as a significant creases with sitting, weight-bearing as in anatomy. Briefly, the spine is composed of contributor towards standing, walking up the stairs, forward bones, nerves, ligaments, joints, muscles flexion, sexual intercourse and menstrual and a unique structure called the inter- low back pain. periods. Pain from the sacroiliac joint vertebral disc. is best diagnosed clinically. There is no Intervertebral disc value to a radiological examination. The Lumbar vertebrae The intervertebral disc is a layer of treatment is usually a fluoroscopically There are five lumbar vertebrae. The strong, soft tissue interposed between guided intra-articular steroid injection. anterior part of each vertebra is called the vertebral bodies. It is deformable. Radiofrequency rhizotomy of the sacro- the vertebral body. It is a box shaped The structure of the intervertebral disc iliac joint is also an option. structure. The top and bottom surfaces is unique. It is designed to transfer the are smooth and perforated by tiny holes. load from the upper vertebra to the lower Muscles of the lower back Projecting from the back of the vertebral vertebra without collapsing; deformable There are three major groups of body are two solid pillars of bone called enough to accommodate rocking move- muscles in the lower back: the Psoas major pedicles. There is a sheet of bone that ment of the spine; and sufficiently strong which lies on the anterolateral aspect of projects from each pedicle towards the to be not injured during movement. The the lumbar spine; the Quadratus Lum- midline called the lamina, thus forming intervertebral disc has a central soft core borum and the intertransversarii laterales a neural arch. The arch surrounds the known as the nucleus pulposus. It is connect the lateral aspect of the spine nerve elements that pass through the surrounded by collagen fibers arranged and the posterior lumbar paraspinous spine. Narrowing of this arch is known in a highly organized pattern called an- muscles, which cover the posterior aspect as central stenosis. Projecting from the nulus fibrosus. The third component of the spine. posterior aspect of the vertebra are four of the intervertebral disc is the vertebral 379 Volume 95 No. 12 De c e m b e r 2012 Piriformis muscle causes of lumbar facet joint pain are Sacroiliac joint pain The piriformis muscle lies anterior osteoarthritis, rheumatoid arthritis, Sacroiliac joint dysfunction or sacro- to the gluteal muscles. It originates from fracture of the facet joint and capsular iliitis presents as a pain in the lumbosacral the sacrum and attaches to the greater tear. It is exacerbated with extension of region, usually with radiation to the leg. trochanter of the femur. The sciatic nerve the spine or axial rotation of the spine. It may are may not be associated with usually passes below the piriformis mus- Radiofrequency rhizotomy is a long-term piriformis muscle spasm, in which case cle, but in approximately 15% of cases option for lumbar facet joint pain. It is the patient presents with radicular pain. it passes through the muscle. A spasm a procedure in which pain signals are Management of this pain is usually a of the piriformis muscle will irritate the “turned off” through the use of heated sacroiliac intra articular joint injection sciatic reproducing radicular symptoms electrodes applied to the sensory nerves under fluoroscopy, or trigger point injec- to the lower extremity. The piriformis from the facet joints. Once the pain from tions to the piriformis muscle followed muscle is closely related to the sacroiliac the lumbar facet joints is decreased, pa- by stretching. joint and the hip joint. Dysfunction of tients benefit from lumbar stabilization the sacroiliac joint may cause spasm of or core strengthening exercises. Hip joint pain the piriformis muscle inducing radicular This usually presents as pain in the symptoms in the lower extremity. It Hip joint lower back, gluteal region, groin, upper is diagnosed by stretching the muscle, Pain from the hip joint may radiate thigh or outer buttocks. The pain may which reproduces the pain. An EMG of into the lower back, gluteal region or the radiate down the leg. It may also be associ- the muscle may be helpful in detecting groin. It may also radiate down the leg. ated with piriformis syndrome. An intra- hyperactivity or spasms that may result Prolonged hip joint pain can result in articular steroid injection is diagnostic as in irritation or compression of the sciatic sacroiliac joint dysfunction and muscle well as therapeutic. It is performed under nerve. The treatment is to stretch the spasms in the lower back. fluoroscopy guidance. muscle with or without trigger point injections. In some of the more refractory A p a t i e n t p r e s e n t i n g w i t h l o w Trochanteric bursitis cases botulinum toxin injections have b a c k p a i n a n d l o w e r e x t r e m i t y The greater trochanteric bursa is been helpful. p a i n m a y b e s u f f e r i n g f r o m : situated between the femur and the inser- Discogenic pain tion of the gluteus medius and minimus Radiculopathy or radiculitis Injury to the disk can be painful muscles into the greater trochanter of the Radicular pain is a result of inflam- due to two mechanisms. The nerve end- femur. Inflammation of the trochanteric mation or irritation of the spinal nerve ings in the annulus fibrosus are exposed bursa presents as pain over the lateral or its roots. The characteristic radicular to enzymes and breakdown products as aspect of the thigh with radiation down pain (nerve root pain) is usually described a result of the deterioration process of the leg, usually as far as the knee. Pa- by patients as a well defined shooting or the disk. Inflammatory chemical media- tients with low back pain often have a stabbing pain in the lower back that ex- tors are released that trigger nociceptive compensated gait resulting in trochanteric tends into the leg. In most patients with pain at the nerve endings. This causes an bursitis. Very often lateral hip pain may be lumbar radiculopathy the pain radiates inflammation of the spinal nerve root caused by tendinitis of the gluteal muscles into the leg below the knee after the ankle resulting in radicular pain to the lower which in turn inflames the trochanteric level. The distal symptoms are usually extremity. Radicular pain caused by a bursa. It is very common in middle aged numbness and tingling. Radiculopathy herniated nucleus pulposus is aggravated women and is also associated with obesity and radiculitis are usually in a specific by activities such as lifting, bending, and arthritis. Diagnosis may be made by dermatomal distribution. This implies straightening, sneezing or coughing or any eliciting tenderness over the lateral hip that a nerve root has been affected. This activity that increases nerve root tension or asking the patient to stand on one is distinct from radiation which is not such as straight leg raising. Pain is often leg at a time which reproduces the pain. in any specific dermatomal distribution relieved by standing or sleeping with a pil- Treatment is to correct the etiology of the and is considered a referred pain For low under the knees. An epidural steroid bursitis, NSAID’s, or a steroid injection example, consider a patient presenting injection performed under fluoroscopy into the bursa. with pain in the lower back and leg: if it guidance at the correct level helps decrease is because of a nerve inflammation from inflammation. Knee and ankle joint pain the nucleus pulposus it would be in a Although pain from these joints does very specific sensory dermatome; if it is Facet joint pain not cause lower back pain patients have because of inflammation of the lumbar Inflammation of the facet joints an antalgic gait, resulting in exacerbation facet joint, then it is not along a sensory causes pain in the lower lumbar region of their lower back pain. distribution. with a referral pattern to the lower ex- Pain from lumbar facet joints is tremity. Management of this pain is usu- Muscular pain predominantly in the lower back, with ally lumbar facet intra articular steroid This is a very common cause of acute radiation into the leg usually above injection under fluoroscopy guidance, or lower back pain. Trigger point injections the knee. It is in a non-specific sensory radiofrequency rhizotomy. are injections of local anesthetic per- dermatomal distribution. Some of the formed into a muscle. On examination 380 Medicine & Health/Rhode Island they present as taut bands with hyper- Re f e r e n c e s Pradeep Chopra, MD, is Director, irritable spots. Stretching exercises in 1. Kurz, LT. The pathogenesis and natural Pain Management Center (SNAPA), and conjunction with trigger point injections history of lumbar disc disease: disc degen- an Assistant Professor (Clinical) at the eration and herniation. Semin. Spine Surg. helps relieve this myofascial pain. 1994;6(3):170–9. Warren Alpert Medical School of Brown 2. Saal JS, et al. High levels of inflammatory phos- University. Th e r o l e o f s t e r o i d s in s p i n a l pholipase A2 activity in lumbar disc herniations. Spine. 1990;15:674–8. p a i n Disclosure of Financial Interests 3. Berg A. Clinical and myelographic studies of Inflammation of the nerves has been conservatively treated cases of intervertebral disc The author and/or their spouse/sig- proposed as a significant contributor protrusion. Acta Chir Scand. 1953;104:12–9. nificant other have no financial interests towards low back pain. Nerve roots have 4. Klimiuk PS, et al. Serial measurements of to disclose. been shown to be swollen and inflamed fibrinolytic activity in acute low back pain and sciatica. Spine. 1987;19:925–8. on myelography and during surgery. 5. Dougherty C, Dougherty JJ. Evaluating hip Co r r e s p o n d e n c e The nucleus pulposus induces marked pathology in trochanteric pain syndrome, J Pradeep Chopra, MD inflammatory change in the nerve roots Musculoskeletal Med. Aug 2008;25(9). Southern New England Anesthesia 6. Williams BS, Cohen SP (2009). Greater tro- dura mater and the spinal cord. High chanteric pain syndrome: a review of anatomy, 102 Smithfield Ave levels of inflammatory phospholipase A2 diagnosis and treatment. Anesth Analg. 2009 Pawtucket, RI 02860 activity have been recorded in lumbar disc May;108(5):1662–70. herniations. 7. Johansson A, Hao J, Sjolund B. Local corti- costeroid application blocks transmission in Steroids decrease inflammation by normal nociceptive C fibers. Acta Anaesthesiol inhibiting the action of phospholipase A2. Scand. 1990;34:335–8. Phospholipase A is an enzyme responsible for the release of arachidonic fatty acids from cell membranes at the site of inflam- mation. This is the rate limiting step in the production of prostaglandins and leukotriens. They also block transmission of no- ciceptive C fiber. Blocking the transmis- sion of nociceptive input is attributed to a direct membrane action and not to an anti-inflammatory effect of the steroid.

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