Biopsychosocial Influence on Shoulder Pain

Chronic shoulder pain is a common, costly, and disabling problem for society. The identification of factors predictive of the development of chronic shoulder pain is necessary to develop innovative and effective treatments to reduce the societal impact of shoulder disorders. In previous work the investigators identified a genetic and psychological subgroup that robustly predicted heightened shoulder pain responses in a pre-clinical cohort and poor 12 month shoulder pain recovery rates in a clinical surgical cohort. In this follow-up study the investigator proposes to test how interventions tailored to the high risk subgroup affect pain responses in a pre-clinical cohort.

The optimal theorized match for the identified high-risk subgroup is a combination of personalized pharmaceutical and education interventions. This combined personalized intervention versus a placebo pharmaceutical and general education intervention group is the primary comparison of interest. Also, an evaluation of the individual effect of personalized pharmaceutical and educational interventions will be part of the study. Such comparisons will provide important information on what the active portion of the combined personalized intervention may be.

Potential subjects will be screened and those meeting the high-risk criteria based on COMT genotype for high pain sensitivity and pain catastrophizing questionnaire score will be eligible for randomization into intervention groups (stratified by sex). Exercise induced shoulder injury will serve as the pain generating mechanism on Day 1 and participants will receive pharmaceutical and education interventions over Days 1-4, and Days 2-4 respectively. Statistical analysis will determine whether the combined personalized intervention group experienced shorter shoulder pain duration, lower peak pain intensity, or decreased upper-extremity disability and determine which molecular, psychological, and pain sensitivity regulation mechanisms are associated with pain relief. A preliminary analysis is planned after the first 300 subjects are equally randomized to the 4 intervention groups. The comparison of interest for the preliminary analysis is the combined personalized intervention group with the placebo and general education group for the primary outcome. Depending on the results of this preliminary analysis the randomization pattern may change, with details of these changes available in the protocol paper.

Inclusion Criteria:

• English speaking

Exclusion Criteria:

• chronic pain (> 3 months) in any area,

• currently experiencing neck or shoulder pain,

• previous history of neck or shoulder pain (operationally defined as experiencing neck or shoulder pain for longer than 48 hours or seeking medical treatment for neck or shoulder pain),

• neurological impairment of the in the upper-extremity (determined by loss of sensation, muscle weakness, and reflex changes),

• regular participation in upper-extremity weight training,

• currently or regular use of pain medication, and

• previous history of upper-extremity surgery.

Additional exclusion criteria for propranolol administration are reported history of or

Presence of any of the following cardiovascular conditions:

• clinically significant abnormal 12-lead ECG,

• sinus bradycardia (resting heart rate below 55 beats per minute),

• greater than first degree heart block,

• cardiac failure,

• coronary artery disease,

• uncontrolled hypertension (resting systolic blood pressure above 140 mm Hg), or hypotension (resting systolic blood pressure below 90 mm Hg),

• Wolff-Parkinson-White syndrome.

Non-cardiovascular reasons for study exclusion include:

• bronchial asthma,

• nonallergic bronchospasm,

• history of recent major surgery requiring general anesthesia,

• diabetes,

• pregnancy,

• major depression.