CLASSIFICATION OF LOW BACK PAIN Hazel Jenkins B.Med.Sci., M.Chiro. * INTRODUCTION differ between these classification systems there is an underlying distinction of four clinical patterns: simple Low back pain is one of the leading causes of health mechanical low back pain; low back pain with radiculopathy; problems in the developed world. The yearly prevalence serious pathological low back pain; and low back pain with of low back pain varies from 5% to as high as 65%1-5 the a psychological overlay. lifetime prevalence can range up to 84% 2,4,5 and the monthly prevalence has been placed between 35% and These 4 categories distinguish the level of treatment each 37%6. Low back pain has a high rate of disability patient needs. Simple mechanical low back pain can be associated with it, which has led to an escalation in the treated and is amenable to conservative care. Low back medical based costs as a result of low back pain2. Many pain with radiculopathy can be treated with conservative people have their first episode of low back pain in their care but increased ongoing assessment is required to late teens or early twenties and these episodes frequently ensure that the treatment is effective and symptoms are not reoccur throughout adult life leading to a chronic progressing. Serious pathological low back pain requires condition7. It is these chronic conditions, with their further investigation before any treatment is administered resultant psychosocial components, that lead to the and immediate referral for medical evaluation is necessary. greatest medical based costs2. Therefore, it becomes Finally, low back pain with a psychological overlay requires imperative that correct diagnosis of low back pain be made concurrent conservative chiropractic care and as early as possible, with the best treatment applied, to psychological assessment. prevent initial acute episodes from becoming a chronic reoccurrence. We will therefore consider an algorithmic approach to diagnosis between these categories to facilitate the DIAGNOSIS OF LOW BACK PAIN evaluation of low back pain. We will then look at specific disease entities within each category and how these may Low back pain is a complex symptom with many diverse be diagnosed. causes for its presentation. There is no other part in the body that contains so many potentially pain causing ALGORITHMIC CATEGORISATION OF LOW BACK structures8 in such a small area. This makes forming a PAIN precise diagnosis as to the tissue causing the low back pain very challenging. The formation of a medical diagnosis is Algorithms provide an excellent screening tool for general imperative to enable the clinician to arrive at a suitable categorisation. Although their use has been criticised as treatment for the pain8. In 90% of low back pain cases, too limited in a definitive diagnosis of low back pain13, however, there is an underlying mechanical cause to the they can be used effectively to screen a patient for their low back pain9 that will resolve itself within two to eight general category of low back pain presentation. weeks 4,10,11 with minimal treatment. From this it can be Furthermore, algorithms provide an easily reproducible concluded that in a majority of cases knowledge of a and time effective method of ensuring that no potentially definitive tissue in lesion will not dramatically effect a serious signs and symptoms are missed. The therapist patient’s long-term prognosis. The more important issue should be encouraged to implement an algorithmic in the diagnosis of low back pain is differentiating these approach to the categorisation of low back pain such as benign mechanical causes of low back pain from the more the one that will be presented here. This will provide serious and pathological causes that do require immediate primary care practitioners with a reliable method of treatment10,12. This particularly becomes an important ensuring that their patients receive the most appropriate consideration for manual therapists who specifically treat care. the mechanical causes of low back pain. The algorithm (see Figure 1) consists of several key A number of classification systems for low back pain have questions that can be screened in the history to categorise been postulated that focus more on the level of pathology each patient. Relevant physical examination findings are and less on the specific structures involved4,8,12. Although then used to confirm that categorisation. the precise categories and the methods of determination SIMPLE MECHANICAL LOW BACK PAIN * Printing Requests and Correspondence A condition that falls into the simple mechanical low back Hazel Jenkins pain category is particularly amenable to conservative 18 Manor Road care. This category contains many benign conditions of HORNSBY, NSW. 2077. Australia. the low back, which are self-resolving within 2-8 Email: [email protected] weeks4,10,11. The main goal of treatment is to decrease the ACO Volume 10 • Number 2 • November 2002 91 DIAGNOSTIC PROBLEM SOLVING OF LBP JENKINS Chief Unilateral / bilateral, poorly Complaint : localised dull pain above the 1 Low Back Pain knee Unillateral, shooting, w ell 2 localised pain below the knee Leg Pain Tw o or more nerve roots One dermatome 3 affected or bilateral, bizarre shooting pain Bow el and bladder Associated w ith pins and disturbances, 2 Associated needles, numbness, saddle anaesthesia Pain w eakness, clumsiness Multi-dermatomal 3 Loin, Abdomen or Pelvic Pain 3 Thoracic Pain 3 Stocking 4 Distribution Generalised or Non-anatomical 4 Pain Severe 3 Traumatic Minor 1 or 2 History of bone softening 3 Onset conditions Constant, progressive 3 Insidious First time or few recurrences 1 or 2 Long-term history w ith recurrence 4 Constant pain, no change w ith 3 movement, rest or time Increases w ith activity or tow ards the end of day, decreases w ith 1 or 2 Aggravating rest and Relieving Pain w orse w ith recumbancy, at 3 Factor s night Pain w orse at start of day 2 or 3 Writhing or cramping pain 3 Previous history of cancer or a 3 systemic condition Medical History Unexplained w eight loss 3 Key to Algorithm and Systems 1: Simple Mechanical Low Back Pain Systemically unw ell 3 Re vie w 2: Low Back Pain with Radiculopathy Associated organic or other joint 3 3: Serious Pathological Low Back Pain symptoms 4: Low Back Pain with Psychological Overlay Associated compensation claim 4 Psychosocial Excessive pain 4 His tor y Depression, anxiety, somatization 4 Positive nerve tension signs or 2 or 3 valsalva Widespread neurology 3 Structural deformity 3 Physical Persisting severe lumbar flexion 3 Exam in at io n Positive abdominal exam 3 Conflicting examination signs 4 Sensory or motor loss in one 2 dermatone Figure 1 : An algorithmic approach to the categorization of low back pain to direct chiropractic treatment ACO 92 Volume 10 • Number 2 • November 2002 DIAGNOSTIC PROBLEM SOLVING OF LBP JENKINS length of disability time and to prevent chronicity and and diffuse and there may be associated referral to the associated psychological overlay. There are many different posterior thigh and buttock13. The muscle often spasms causes of simple mechanical low back pain and it is not after injury, and hence, trigger point formation may occur, always possible to differentiate the exact tissue causing leading to a future myofascial pain syndrome. the pain. However, some of the more common low back pain syndromes are presented below. Spondylolysis and Spondylolisthesis Spondylolysis refers to a fatigue fracture of the pars Facet Syndrome interarticularis15 whereas spondylolisthesis refer to a Facet syndrome may be the primary cause of low back forward slippage of one vertebra upon the one below it16. 13 pain in as many as 15% to 20% of cases . The pain is Spondylolytic spondylolisthesis is most common at L5 in caused by pinching of the synovial folds within the joint adolescent athletes, particularly in those who in engage itself 4. This pain tends to be increased by extension and in repetitive extension type activities4,15. Non- homolateral lateral flexion or rotation movements4,13 where spondylolytic spondylolisthesis, on the other hand, is compression within the facet joint is increased. In more common at L4 in older people due to a degenerative particular the lumbar Kemp’s manoeuvre specifically elongation of the pars interarticularis8. The most common reproduces the pain4. The pain is usually described as a symptom is that of local low back pain aggravated by lateral sharp or catchy, localised low back pain4,13 possibly extension or activity, and relieved by rest4,13,15,16. However, with some deep, dull, ill-defined sclerotomal pain extending it is also possible to have radicular signs of nerve to the posterior buttocks and thigh4,8,13. The pain is usually entrapment, or signs of central stenosis due to the forward decreased by distraction of the spine13 and there is an slippage4,8 or for the patient to be asymptomatic4,16. absence of neurological deficits and nerve root tension Therefore, spondylolisthesis may form part of a more signs4,8. serious clinical picture and radiological evaluation is required to monitor the forward slippage of the vertebra4. Sacroiliac Joint Syndrome A sprain of the anterior or posterior sacroiliac joint LOW BACK PAIN WITH RADICULOPATHY ligaments is a frequently overlooked source of low back pain4,13. The pain itself presents similarly to that of facet Low back pain with radiculopathy is a potentially more syndrome. However, the sharp low back pain is localised serious form of mechanical low back pain. It can still be to the sacroiliac joint and the referred pain may extend effectively managed with conservative care but frequent posteriorly down the thigh or anteriorly to the groin reassessments are required to ensure that improvements region8,13. Once again no neurological deficits or nerve are occurring with treatment and that symptoms are not tension signs will be found on examination8.