Lower thoracic spine extension mobility is associated with higher intensity of thoracic spine pain

To evaluate the association of thoracic spine (TS) posture and mobility with TS pain.

Participants with TS pain reported maximum, average, and night pain in TS area, and pain summary score was calculated. Upright and sitting TS postures were evaluated by inspection. TS posture and mobility (flexion and extension) were recorded using an inclinometer and a tape measure, respectively. Correlations between posture and mobility assessments were calculated using Spearman rank correlation, the association of TS posture and mobility with TS pain by logistic regression analysis.

The participants' (n = 73, 52 females, age range 22-56) TS pain duration was 12 weeks on average. The correlations for measurements of TS posture and flexion mobility were higher than correlations of other TS measurements being between 0.53 and 0.82. Decreased extension mobility of the upper (from 1^st to 6^th TS segments; Th1-Th6) TS was associated with higher worst pain (OR 1.04, 95% CI 1.00-1.07) and whole TS with pain sum score (OR 1.05, 95% CI 1.01-1.08). Less kyphotic whole TS was associated with lower pain sum score (OR 0.96, 95% CI 0.92-1.00). Greater flexion mobility of upper and lower (Th6-Th12) TS were associated with lower pain sum score (OR 0.96, 95% CI 0.91-1.00, and OR 0.96, 95% CI 0.91-1.00, respectively).

Reduced thoracic extension mobility was associated with higher pain scores and the greater flexion mobility with lower pain scores. Future research is warranted to evaluate if treatments geared toward TS extension mobility improvements would result in lower TS pain.