Measurement of the number of lumbar spinal movements in the sagittal plane in a 24-hour period.

PURPOSE: Little is known about the number of spinal movements in the sagittal plane in daily life, mainly due to the lack of adequate techniques to assess these movements. Our aim was to measure these movements in asymptomatic volunteers. METHODS: Two sensor strips based on strain gauge technology (Epionics SPINE system) were fixed on the skin surface of the back parallel to the spine on a total of 208 volunteers without back pain. First, the lordosis angle was determined during relaxed standing. The volunteers were then released to daily life. The increases and decreases in the back lumbar lordosis angle over a period of 24 h were determined and classified into 5° increments. Changes in the lordosis angle greater than 5° were considered. RESULTS: The median number of spinal movements performed within 24 h was approximately 4,400. Of these movements, 66 % were between 5° and 10°. The proportions of higher-magnitude lordosis angle changes were much lower (e.g., 3 % for the 20-25° movement bin). Surprisingly, the median total number of movements was significantly higher (29 %) in women than in men. Large inter-individual differences were observed in the number of movements performed. The volunteers spent a median of 4.9 h with the lumbar spine flexed between 20° and 30° and only 24 min with the spine extended relative to the reference standing position. A median of 50 movements reached or exceeded full-flexion angle and zero movements full-extension angle. CONCLUSIONS: These data illustrate the predominantly small range of movement of the spine during daily activities and the small amount of time spent in extension. These unique data strongly contribute to the understanding of patients' everyday behavior, which might affect the development and testing of spinal implants and the evaluation of surgical and nonsurgical treatments.

Comparative evaluation of a novel measurement tool to assess lumbar spine posture and range of motion.

PURPOSE: The diagnosis of low back pain pathology is generally based upon invasive image-based assessment of structural pathology, but is limited in methods to evaluate function. The accurate and robust measurement of dynamic function may assist in the diagnosis and monitoring of therapy success. Epionics SPINE is an advanced strain-gauge measurement technology, based on the two sensor strips SpineDMS system, which allows the non-invasive assessment of lumbar and thoraco-lumbar motion for periods of up to 24 h. The aim of this study was to examine the reliability of Epionics SPINE and to collect and compare normative data for the characterisation of spinal motion in healthy subjects. Furthermore, the identification of parameters that influence lumbar range of motion (RoM) was targeted. METHODS: Spinal shape was measured using Epionics SPINE in 30 asymptomatic volunteers during upright standing, as well as maximum flexion and extension, to check intra-rater reliability. Furthermore, back shape was assessed throughout repeated maximum flexion and extension movements in 429 asymptomatic volunteers in order to collect normative data of the lordosis angle and RoM in different gender and age classes. RESULTS: The lordosis angle during standing in the healthy collective measured with Epionics SPINE was 32.4° ± 9.7°. Relative to this standing position, the average maximum flexion angle was 50.8° ± 10.9° and the average extension angle 25.0° ± 11.5°. Comparisons with X-ray and Spinal Mouse data demonstrated good agreement in static positions. Age played a larger role than gender in influencing lumbar posture and RoM. CONCLUSIONS: The Epionics SPINE system allows the practical and reliable dynamic assessment of lumbar spine shape and RoM, and may therefore provide a clinical solution for the evaluation of lower back pain as well as therapy monitoring.

Measurement of Lumbar Spine Functional Movement in Low Back Pain.

OBJECTIVES: Individuals with low back pain (LBP) present with alterations or limitations of spinal mobility. The identification of simple clinical methods for evaluating functional movement of the spine is necessary to allow quantification of the degree of movement impairment and permit monitoring of patient improvement with rehabilitation. This study evaluated movement of the spine in 20 patients with chronic nonspecific LBP compared with 19 pain-free participants using a novel measurement device that permits the dynamic assessment of spinal movement in a rapid and subject-specific manner. METHODS: Two flexible sensor strips were fixed paravertebrally to the spine with each sensor strip measuring angles in 12 predetermined, adjacent, 25-mm-long segments. Maximum range of motion (ROM) and average angular velocity (AAV) of lumbar and pelvic movement were measured within identical angular and temporal frames during the descending and ascending phase of active lumbar flexion, extension, rotation, and lateral flexion following a standard choreography. Participants with LBP completed a number of questionnaires including the Tampa Scale of Kinesiophobia, Pain Catastrophizing Scale, and Spielberger State-Trait Anxiety Inventory. RESULTS: Across all movements, the individuals with LBP displayed 10% to 15% less ROM (P<0.05) and 15% to 30% less AAV (P<0.05) at both the pelvis and lumbar regions compared with controls. ROM as well as AAV, in most cases, were negatively correlated (R=-0.49 to -0.75) with the Tampa Scale of Kinesiophobia, Pain Catastrophizing Scale, and Spielberger State-Trait Anxiety Inventory in the LBP group (all P<0.05) especially during the initial descending phase of movement. DISCUSSION: This study provide support for the utility of this device for quantifying movement impairments in individuals with fairly low levels of LBP and general functional limitations. The results show that velocity measurements rather than ROM show the greatest differences in individuals with LBP compared with asymptomatic participants. Impaired lumbar and pelvis movement was correlated to the individuals with LBP's degree of anxiety, fear, and catastrophizing.

Automatic distinction of upper body motions in the main anatomical planes.

The assessment of spinal mobility and function is gaining clinical importance for the diagnosis and monitoring of low back pain, but its measurement and evaluation remains difficult. As a critical step towards non-supervised assessment of spinal functional, the aim of this study was to assess the efficacy of symmetrical sensors fixed to the sides of the spinal column to distinguish between different upper body movements in the main anatomical planes. 429 healthy volunteers underwent a defined choreography including repeated upper body flexion, extension, lateral bending and axial rotation exercises. The movements were assessed using the Epionics SPINE sensor system. Two pattern recognition models were developed and applied to distinguish between the different movements in a frame-by-frame manner, as well as for whole motion sequences. On average, it was possible to differentiate between different upper body movements with a sensitivity of over 96% for both modelling approaches. The largest type II error was the incorrect identification of extension, possibly due to deviations from the reference standing posture during measurements and small changes in the lordotic angle during extension. The use of two sagittal sensors attached symmetrically to the back therefore seems to allow the distinction of upper body movements in a robust manner, and therefore opens perspectives for the unsupervised recognition of movements and functional activity over extended periods.

Velocity of lordosis angle during spinal flexion and extension.

The importance of functional parameters for evaluating the severity of low back pain is gaining clinical recognition, with evidence suggesting that the angular velocity of lordosis is critical for identification of musculoskeletal deficits. However, there is a lack of data regarding the range of functional kinematics (RoKs), particularly which include the changing shape and curvature of the spine. We address this deficit by characterising the angular velocity of lordosis throughout the thoracolumbar spine according to age and gender. The velocity of lumbar back shape changes was measured using Epionics SPINE during maximum flexion and extension activities in 429 asymptomatic volunteers. The difference between maximum positive and negative velocities represented the RoKs. The mean RoKs for flexion decreased with age; 114°/s (20-35 years), 100°/s (36-50 years) and 83°/s (51-75 years). For extension, the corresponding mean RoKs were 73°/s, 57°/s and 47°/s. ANCOVA analyses revealed that age and gender had the largest influence on the RoKs (p<0.05). The Epionics SPINE system allows the rapid assessment of functional kinematics in the lumbar spine. The results of this study now serve as normative data for comparison to patients with spinal pathology or after surgical treatment.

A novel system for the dynamic assessment of back shape.

Low back pain can be exacerbated by poor posture, particularly over extended stationary periods such as when sitting or standing. The repetitive determination of back shape could allow an ongoing assessment of subject specific posture to better understand the mechanisms of back pain. The portable measurement system SpineDMS(©) allows the dynamic, extended assessment of back shape in six segments of the lumbar and lower thoracic spine. The objective of this study was to assess the accuracy and repeatability of the system to determine its applicability for assessing back shape in patients. To assess the accuracy and repeatability of angle measurements, six SpineDMS(©) sensor strips (three systems) were repeatedly bent taut over a range of defined arcs. Measurements of spinal curvature were additionally conducted in 10 volunteers who performed flexion and extension exercises, with all results compared against reference marker data. The measurement sensors had a high accuracy and excellent repeatability (mean intraclass correlation coefficient (ICC) >0.98), with test-retest reliability ICCs of >0.98. Measurements in volunteers showed that SpineDMS(©) was capable of detecting the shape and movement of the human back. This study showed that SpineDMS(©) could be deployed as a reliable diagnostic tool for back posture, as well as movements in the sagittal plane.