SPINAL AND PELVIC POSTURAL ASSESSMENT IN SUBJECTS WITH AND WITHOUT MECHANICAL LOW BACK PAIN USING SURFACE TOPOGRAPHY

Low back pain (LBP) is a common musculoskeletal problemthat not only causes physical morbidity as well as socio-economic loss in thecommunity. The lifetime incidence rates of this clinical condition have beenestimated to be between 50-90%.1

Investigators have classified thedifferential diagnosis of low back pain mainly into mechanical causes (noprimary inflammatory or neoplastic cause – 97%), visceral causes (no primaryinvolvement of the spine – 2%), and non mechanical causes (Neoplasia,Infection, inflammatory arthritis etc – 1%). Many uncomplicated low back paincases are assumed to result as a result of muscle sprains and strains,ligamentous injuries, and spinal degenerative changes. Disc herniation withnerve root compression or irritation has been proposed to be the most commoncause of neurologic abnormalities.2

 The lumbo-sacral region, being the most important regionin the vertebral column in terms of mobility and weight bearing, mechanicaldisorders of this region cause LBP. Various studies have examined therelationship between changes in the angles of the lumbar spine and LBP and haveshown significant differences in saggital profile of the lumbar spine betweenasymptomatic subjects and patients with LBP.3

 Loss or flattening of the normal lumbar lordosis is animportant clinical sign of back problems as the patient is thought to keep thespine in a upright and straight position, to reduce pain. But some studies suggeststhat, patients with chronic LBP have either no difference or increased lumbarlordosis with respect to controls, which shows that, variations of the lumbar spine may / may not relate to reportedsymptoms.4 These lumbaranatomical changes would lead to an increased anterior tilt of the pelvis andan exaggerated lumbar lordosis during relaxed standing.5

There still exists acontroversy in the scientific literature regarding lumbo-sacral posture and lowback pain. Thoracic kyphosis, lumbar lordosis, pelvic tilt, and abdominalstrength are the most investigated parameters, with respect to low back pain.6

Conventionally, LBP assessment is based on clinicaldiagnosis and is best established with an abnormality, evident in a radiograph.For the detection of pathological changes of the spine shape, the gold standardremains to be, the clinical examination along with radiological techniques suchas X-ray, CT and MRI until today. The radiation from these diagnosticprocedures leads to a very critical deployment for follow-up examinations, particularlyin young patients. For this reason, simple, but inaccurate and poorly reliablemethods were developed for follow-up examinations of the spine like thekyphometer or the curve ruler. More advanced methods like VICON Video System orthe ultrasound-based Zebris- System were developed eventually, which were basedupon the placement of marker on the skin over bony landmarks of the patients. Thesetechniques were then found, to lead to measuring errors due to a possible shiftof the skin over the underlying bony structures.7

 This study uses surface topography to compare the spinaland pelvic patterns in patients with LBP with that of normal subjects. It is avalidated, reliable, precise, radiation-free and inexpensive method fordetecting the spinal posture, developed in early 1980’s, based on thetechnology of raster-stereography (RSG). This might help resolve some of thecontroversy and be useful in identifying patterns that may be associated withLBP. To our knowledge, no studies have been reported to be done, on spinal andpelvic postural deviations in LBP using surface topography. The paucity ofscientific information available to support the spinal and pelvic posturaldeviations in LBP may be tackled with this study. This may aid in the diagnosisand treatment of LBP patients and also affect the planning of a proper exerciseprogram for the back / abdominal muscle.

HYPOTHESIS:Subjects withmechanical LBP have spinal and pelvic postural deviations when compared withthe normal subjects.