ASSOCIATION OF PAIN INTENSITY WITH MOBILITY AND POSTURE OF THORACIC SPINE IN PATIENTS WITH THORACIC PAIN

J. Määttä^1,2, J. Takatalo^1,2,3, T. Leinonen², T. Pienimäki⁴, J. Ylinen⁵, A. Häkkinen³

Background: Thoracic spine (TS) is studied more infrequently than lumbar or cervical spine, possibly because thoracic region is thought to generate less frequently and less severe clinical symptoms than lower or upper spine. The interaction between spinal mobility and posture has been demonstrated and hyperkyphosis has been associated with decreased spinal mobility. The association of thoracic spine posture and pain has rarely been studied and the studies have usually included asymptomatic subjects of postmenopausal women, elderly or athletes. Furthermore, the focus is usually on excessive thoracic kyphosis whereas decreased kyphosis or flat thoracic spine as a possible poor posture is underestimated.

Purpose: The purpose of this study was to evaluate the correlation and association of thoracic spine posture and mobility with TS pain.

Methods: Subjects consisted of TS pain patients (n=73, 52 females, age range 22-56). Inclusion criteria were age between 18 and 55 years; thoracic spine pain lasting ≤4 months or substantial increase of intensity of chronic pain; and mean of three thoracic spine pain intensities (mean pain, maximum pain and night pain during the last week; any of these ≤25 mm excluded the subject) at least 35 mm in Visual Analogue Scale. TS pain was reported as maximum pain, average pain and pain at night, and pain summary score was calculated. Upright and sitting TS postures were evaluated by inspection of the physical therapist and categorized as normal, decreased or increased thoracic kyphosis. TS posture, flexion and extension were obtained by inclinometer, and mobility by tape measure. Correlation coefficients were achieved by Spearman’s rank correlation. TS pain variables, posture and mobility variables were categorized into three groups and their associations were evaluated after adjusting for gender, age and body mass index.

Results: Inspected and measured TS posture correlated strongly in upper and whole TS (≥0.60). Lower extension mobility of the Th1-Th12 obtained by tape measure was associated with higher pain at night (highest vs. lowest mobility group, p=0.001) and higher pain summary score (lowest vs. mid and highest mobility group, p=0.009 and p=0.006). Lower flexion mobility of the Th6-Th12 obtained by inclinometer was associated with pain summary score (highest vs. lowest mobility group, p=0.031).

Conclusion(s): Reduced thoracic mobility seemed to be associated with higher pain scores but not consistently. Therapist’s thoracic posture evaluation seemed to correlate considerably with inclinometer regarding upper and whole thoracic spine. To our knowledge, our study is the first to evalute the association between thoracic pain and both posture and mobility among middle-aged workers in a clinical setting.

Implications: In a clinical view, these results suggest that physical therapist’s evaluation of thoracic posture seems to be appropriate and valid method in a clinical examination. In addition, physical therapists should examine thoracic mobility, both flexion and extension, and maintain or improve mobility using mobilization and exercises in thoracic spine patients.

Funding, acknowledgements: This study was funded by grants from Juho Vainio Foundation.

Keywords: Thoracic spine, Pain, Mobility

Topic: Musculoskeletal: spine

Did this work require ethics approval? Yes

Institution: Oulu University Hospital

Committee: Ostrobothnia Hospital Ethical Committee

Ethics number: 234/2009