Center of pressure excursion as a measure of balance performance in patients with non-specific low back pain compared to healthy controls: a systematic review of the literature

Abstract

Over the past 20 years, the center of pressure (COP) has been commonly used as an index of postural stability in standing. While many studies investigated COP excursions in low back pain patients and healthy individuals, no comprehensive analysis of the reported differences in postural sway pattern exists. Six online databases were systematically searched followed by a manual search of the retrieved papers. The selection criteria comprised papers comparing COP measures derived from bipedal static task conditions on a force-plate of non-specific low back pain (NSLBP) sufferers to those of healthy controls. Sixteen papers met the inclusion criteria. Heterogeneity in study designs prevented pooling of the data so only a qualitative data analysis was conducted. The majority of the papers (14/16, 88%) concluded that NSLBP patients have increased COP mean velocity and overall excursion as compared to healthy individuals. This was statistically significant in the majority of studies (11/14, 79%). An increased sway in anteroposterior direction was also observed in NSLBP patients. Patients with NSLBP exhibit greater postural instability than healthy controls, signified by greater COP excursions and a higher mean velocity. While the decreased postural stability in NSLBP sufferers further appears to be associated with the presence of pain, it seems unrelated to the exact location and pain duration. No correlation between the pain intensity and the magnitude of COP excursions could be identified.

Balance Confidence Is Related to Features of Balance and Gait in Individuals with Chronic Stroke

“…COP excursion measures provide an indirect quantification of activity levels in the motor system [25] during quiet standing. Changes in the position of the COP contribute to the control of the position of the body's centre of mass [26].…”

Postural balance in low back pain patients: criterion-related validity of centre of pressure assessed on a portable force platform

“…The mVel is recommended as outcome parameter for postural stability [7,12], the APdispl is used in a recent study [4], and the RRvel is used in order to quantify the visual contribution to posture. The RRvel is usually greater than one, and an RRvel of 1.3 indicates that mVel is increased by 30% in EC tests compared to EO.…”

“…The term ''persistent low back pain'' is often used to describe subacute, chronic, and recurrent pain. Several studies indicate that LBP patients have poorer postural stability than healthy controls [6,7]. It is not known whether poorer postural stability is a consequence or a predictor of LBP, but some evidence suggests that people with poor postural stability have an increased risk of LBP [8].…”

“…The influence of LBP on postural balance is complex [10] and affected by co-existing factors: pain, fear of pain, positive neurologic findings, adoption of an alternate movement strategy, and low muscular conditioning [4,7,[9][10][11].…”

The Quantified Indices for Compensatory Patterns for Low Back Pain and Outcome Measures

“…Several other studies focusing on typical movement patterns in older adults with LBP identified increased postural sway and decreased lumbar spine motion [33,34]. It has been reported that individuals with LBP demonstrate significantly decreased postural stability during one-leg standing and other clinical balance tests [7,8,14].…”