ORIGINAL ARTICLE Poststroke Shoulder Pain: Its Relationship to Motor Impairment, Activity Limitation, and Quality of Life John Chae, MD, ME, Don Mascarenhas, MD, David T. Yu, MD, Andrew Kirsteins, MD, Elie P. Elovic, MD, Steven R. Flanagan, MD, Richard L. Harvey, MD, Richard D. Zorowitz, MD, Zi-Ping Fang, PhD ABSTRACT. Chae J, Mascarenhas D, Yu DT, Kirsteins A, Elovic EP, Flanagan SR, Harvey RL, Zorowitz RD, Fang Z-P. Poststroke shoulder pain: its relationship to motor impairment, activity limitation, and quality of life. Arch Phys Med Rehabil 2007;88:298-301. Objective: To assess the relationship between poststroke shoulder pain, upper-limb motor impairment, activity limita- tion, and pain-related quality of life (QOL). Design: Cross-sectional, secondary analysis of baseline data from a multisite clinical trial. Setting: Outpatient rehabilitation clinics of 7 academic med- ical centers. Participants: Volunteer sample of 61 chronic stroke survi- vors with poststroke shoulder pain and glenohumeral sublux- ation. Interventions: Not applicable. Main Outcome Measures: We measured poststroke shoul- der pain with the Brief Pain Inventory question 12 (BPI 12), a self-reported 11-point numeric rating scale (NRS) that assesses “worst pain” in the last 7 days. Motor impairment was mea- sured with the Fugl-Meyer Assessment (FMA). Activity limi- tation was measured with the Arm Motor Ability Test (AMAT) and the FIM instrument. Pain-related QOL was measured with BPI question 23, a self-reported 11-point NRS that assesses pain interference with general activity, mood, walking ability, normal work, interpersonal relationships, sleep, and enjoyment of life. Results: Stepwise regression analyses indicated that post- stroke shoulder pain is associated with the BPI 23, but not with the FMA, FIM, or AMAT scores. Conclusions: Poststroke shoulder pain is associated with reduced QOL, but not with motor impairment or activity limitation. Key Words: Pain; Quality of life; Rehabilitation; Shoulder; Stroke. © 2007 by the American Congress of Rehabilitation Medi- cine and the American Academy of Physical Medicine and Rehabilitation S HOULDER PAIN IS A COMMON complication of hemi- plegia; its reported prevalence ranges between 5% and 84%. 1,2 Numerous studies have reported a relationship between poststroke shoulder pain and limited shoulder external rotation range of motion (ROM), 3 sensory impairment, 4 adhesive cap- sulitis, 5 impingement, 6 subluxation, 7 spasticity, 8 and complex regional pain syndrome (CRPS). 9 Its relationship to motor impairment and activity limitation is less clear. Roy et al 10 showed that stroke survivors with shoulder pain have more severe motor impairment during recovery. Others, however, have reported no relationship between shoulder pain and motor impairment. 6,11 In a study of 108 stroke survivors discharged from a hospital, Wanklyn et al 12 reported that patients with shoulder pain had significantly greater activity limitation than patients without pain, based on their Barthel Index of disability scores. Another study, 4 however, showed no relationship be- tween shoulder pain and the Barthel Index scores. Finally, other authors 2,13 have indicated a relationship between shoul- der pain and pain-related quality of life (QOL). This relation- ship has not been quantitatively demonstrated, however. While the pain experience alone is a sufficient reason for treatment, the importance of treating poststroke shoulder pain is further emphasized if it can be shown that it has a relationship to motor impairment, activity limitation, and QOL. Our objective in this cross-sectional study was to test the hypothesis that poststroke shoulder pain, motor impairment, activity limitation, and pain-related QOL are statistically re- lated. METHODS Participants We analyzed the baseline data of stroke survivors enrolled in a multicenter randomized clinical trial of percutaneous electric stimulation for the treatment of poststroke shoulder pain. 14,15 The clinical trials protocol was approved by the institutional review boards at each participating center. Participants were more than 12 weeks poststroke (hemorrhagic or nonhemor- rhagic) and were at least 18 years old. Participants had (1) shoul- der pain graded as at least 2 on the 11-point numeric rating scale (NRS) of the Brief Pain Inventory 16 question 12 (BPI 12), (2) at least one-half fingerbreadth of inferior glenohumeral separation by palpation with the affected limb in a dependent position From the Cleveland Functional Electrical Stimulation Center, Cleveland, OH (Chae, Yu); Departments of Physical Medicine and Rehabilitation (Chae, Yu) and Biomedical Engineering (Chae), Case Western Reserve University, Cleveland, OH (Mascarenhas); Charlotte Institute for Rehabilitation, Charlotte, NC (Kirsteins); Kessler Medical Rehabilitation Research and Education Corp, West Orange, NJ (Elovic); Department of Rehabilitation Medicine, Mt. Sinai School of Medicine, New York, NY (Flanagan); Rehabilitation Institute of Chicago, Chicago, IL (Harvey); Department of Rehabilitation Medicine, University of Pennsylvania, Philadelphia, PA (Zorowitz); and NeuroControl Corp, North Ridgeville, OH (Fang). Yu is now affil- iated with Virginia Mason Medical Center, Seattle, WA, and Bioness Inc, Santa Clarita, CA; Kirsteins is now affiliated with Moses Cones Health System, Greensboro, NC; and Zorowitz is now affiliated with Johns Hopkins Bayview Medical Center, Baltimore, MD. Presented in part to the Association of Academic Physiatrists, March 2006, Day- tona, FL. Supported in part by the National Institute for Child Health and Human Develop- ment (grant nos. R44HD34996, K12HD01097), the National Center for Research Re- source (grant no. M01RR0080), and by the NeuroControl Corp, North Ridgeville, OH. A commercial party having a direct financial interest in the results of the research supporting this article has conferred or will confer a financial benefit upon the author or 1 or more of the authors. NeuroControl Corp has a direct interest in the content of this article with respect to a device NeuroControl intends to commercialize. Chae is a consultant to NeuroControl. Fang is an employee of NeuroControl. At the time of the study, Yu was a consultant to NeuroControl, but is no longer affiliated with NeuroControl. Reprint requests to John Chae, MD, ME, Dept of Physical Medicine and Rehabil- itation, Case Western Reserve University, MetroHealth Medical Center, 2500 Metro- Health Dr, Cleveland, OH, 44109, e-mail: jchae@metrohealth.org. 0003-9993/07/8803-11158$32.00/0 doi:10.1016/j.apmr.2006.12.007 298 Arch Phys Med Rehabil Vol 88, March 2007