Presence of Latent Myofascial Trigger Points and Determination of Pressure Pain Thresholds of the Shoulder Girdle in Healthy Children and Young Adults: A Cross-sectional Study.

OBJECTIVE: The primary objective of this study was to compare the number of myofascial trigger points (MTPs) and the pressure pain thresholds (PPTs) in the shoulder girdle, on the dominant and nondominant sides, between healthy children and adults. The secondary aim was to assess the correlations between the number of MTPs and the PPTs in these populations. METHODS: A cross-sectional study was performed. Thirty-five children (aged 9.1 ± 1.7 years) and 35 adults (aged 23.4 ± 3.4 years) with no history of shoulder or cervical pathology were included. All participants were examined for MTPs in the shoulder muscles and assessed for PPTs in the neck, shoulder, and tibialis anterior. Parametric and nonparametric tests, effect sizes, and odds ratios were used to determine the differences between groups and sides. Spearman's σ test was used to assess correlations between latent MTPs (LTPs) and PPTs in each group. RESULTS: Children had fewer LTPs than adults did (P = .03). The upper trapezius was the muscle with the largest number of LTPs, affecting 13 adults on the dominant side. Children had lower PPTs compared with adults (P < .05). Correlations between the number of LTPs (on both sides and in total) and PPTs were observed only in adults. CONCLUSIONS: Healthy children have fewer LTPs and lower PPTs in the shoulder girdle than healthy adults. A relationship was observed between sensitivity to pressure and the presence of LTPs in adults, in whom lower PPT was associated with more LTPs. This relationship was not detected in children.

Scapular kinematics pre- and post-thoracic thrust manipulation in individuals with and without shoulder impingement symptoms: a randomized controlled study.

STUDY DESIGN: Randomized controlled trial with immediate follow-up. OBJECTIVES: To evaluate the immediate effects of a low-amplitude, high-velocity thrust thoracic spine manipulation (TSM) on pain and scapular kinematics during elevation and lowering of the arm in individuals with shoulder impingement syndrome (SIS). The secondary objective was to evaluate the immediate effects of TSM on scapular kinematics during elevation and lowering of the arm in individuals without symptoms. BACKGROUND: Considering the regional interdependence among the shoulder and the thoracic and cervical spines, TSM may improve pain and function in individuals with SIS. Comparing individuals with SIS to those without shoulder pathology may provide information on the effects of TSM specifically in those with SIS. METHODS: Fifty subjects (mean ± SD age, 31.8 ± 10.9 years) with SIS and 47 subjects (age, 25.8 ± 5.0 years) asymptomatic for shoulder dysfunction were randomly assigned to 1 of 2 interventions: TSM or a sham intervention. Scapular kinematics were analyzed during elevation and lowering of the arm in the sagittal plane, and a numeric pain rating scale was used to assess shoulder pain during arm movement at preintervention and postintervention. RESULTS: For those in the SIS group, shoulder pain was reduced immediately after TSM and the sham intervention (mean ± SD preintervention, 2.9 ± 2.5; postintervention, 2.3 ± 2.5; P<.01; moderate effect size [Cohen d = 0.2]). Scapular internal rotation increased 0.5° ± 0.02° (P = .04; small effect size [Cohen d<0.1]) during elevation of the arm after TSM and sham intervention in the SIS group only. Subjects with and without SIS who received TSM and asymptomatic subjects who received the sham intervention had a significant increase (1.6° ± 2.7°) in scapular upward rotation postintervention (P<.05; small effect size [Cohen d<0.2]), which was not considered clinically significant. Scapular anterior tilt increased 1.0° ± 4.8° during elevation and lowering of the arm postmanipulation (P<.05; small effect size [Cohen d<0.2]) in the asymptomatic subjects who received TSM. CONCLUSION: Shoulder pain in individuals with SIS immediately decreased after a TSM. The observed changes in scapular kinematics following TSM were not considered clinically important. LEVEL OF EVIDENCE: Therapy, level 4. J Orthop Sports Phys Ther 2014;44(7):475-487. Epub 22 May 2014. doi:10.2519/jospt.2014.4760.