Short summary

The study is a cross-sectional survey, performed in individuals with Spinal Cord Injury (SCI). The design is a mixed-mode analysis, including possibilities for filling out an internet/web or paper based questionnaire. The objective of this study is to survey the self-reported prevalence and severity of shoulder pain, function and quality of life in Danish manual wheelchair users with SCI, being either athlete or non-athlete, and to determine associations between these clinical characteristics adjusted for possible confounding factors like age, gender, and injury level/type.

Rationale

The number of individuals in Denmark with Spinal Cord Injury (SCI) has been estimated to be approximately 3000 persons, with an annual incidence of 10-15 cases per million inhabitants per year for traumatic and non-traumatic injuries, respectively. Individuals with SCI belong to diagnosis-related group with the largest proportion of manual wheelchair users and seem to present with the most pervasive upper extremity problem of shoulder pain, because of the impact from daily life, such as mobility and quality of life, in addition to health care costs. Among individuals with SCI estimates of the prevalence of musculoskeletal pain in the cervical and shoulder region are imprecise, varying from 30%-73%, but equals around three-fold higher prevalence than the general population. This may be due to the fact that the shoulders are their "legs", resulting in a load every time physical activities are performed. The extent and severity of shoulder pain in SCI are anticipated to be related with level and severity of SCI, and thus most severe in tetraplegics, implying the injury to be at a high level of the spinal cord. The most common cause of shoulder pain is overuse, resulting in subacromial impingement syndrome (SIS), Rotator cuff Tendinopathy (RT) and tears. The reason may be due to the partial innervation and imbalanced scapula-thoracic muscles.

Generally, participation in sports activities is recognized to be contributing to long-term health, personal and social wellbeing. However, sport activities for SCI wheelchair athletes is known to increase shoulder loading even more, on top of daily shoulder loads, especially in tetraplegic individuals, due to extensive repetitive shoulder motions with limited rest periods. However, only few studies have specifically compared manual wheelchair users with SCI being either athletes or non-athletes, with respect to frequency and severity of shoulder problems, in addition to quality of life. Despite the well-known positive correlation between repetitive manual wheelchair activity and shoulder pain, one study has reported wheelchair athletes to have lower risk of shoulder pain than non-athletes, which could indicate a healthy athlete effect into sport. However, a larger number of paraplegics placed in the athletic group make the two groups in-comparable and the results may therefore be questioned. Thus, no study has specifically addressed the frequency and severity of shoulder pain in tetraplegics performing wheelchair sports. In the general population, shoulder pain is associated with co-occurring pain at other body sites, primarily in the neck and elsewhere in the upper extremity, therefore addressing these additional body sites are also relevant.

Description of the cohort

Participants with acquired SCI following traumatic or non-traumatic lesions (as consequence of e.g., tumors, herniated disc, infection) with symptoms for at least 2 years of SCI - aged between 18-65 years, registered in the electronic databases/registries (n = 2500) including either 1) Clinic for Spinal Cord Injuries (CSCI), Rigshospitalet, or 2) Spinal Cord Injury Centre of Western Denmark (SCI-CWD), Viborg Regional Hospital. Participants will also be recruited from the outpatient clinic at the 3) Orthopedic Department, Odense University Hospital, and the 4) PTU Rehabilitation Center, Rødovre.

Data and biological material

Difference in presence and severity of shoulder pain, between athlete and non-athletes with SCI (tetraplegic and paraplegic manual wheelchair user), will be recorded by self-reported Wheelchair User´s Shoulder Pain Index (WUSPI)/Performance Corrected Wheelchair User's Shoulder Pain Index (PC-WUSPI)

Supplementary patient-reported outcomes (PRO's), such as 1) Standardized Nordic Questionnaire (shoulder/ neck discomfort), 2) McGill Pain Questionnaire 3) International Spinal Cord Injury Quality of Life Basic Data Set (Three Items), 4) Leisure Time Physical Activity Questionnaire for People with Spinal Cord Injury (LTPAQ-SCI) and as a supplement to this scale participants will be asked about which physical activities they are involved in, in relation to the intensity of physical activities (mild, moderate, and heavy intensity). Finally general demographics include medical history, socio-economic status and assistive devices. The section on participant characteristics and medical history includes questions on marital status, occupational and recreational activities, past and present shoulder pain, shoulder(s) involved, and treatment received/contacts to the health care system.

Collaborating researchers and departments

Department of Sports Science and Clinical Biomechanic, University of Southern Denmark and Health Sciences Research Centre, University College Lillebælt, Odense

• Postdoc Camilla Marie Larsen, PhD

Department of Sports Science and Clinical Biomechanic, University of Southern Denmark

• Associate professor Birgit Juul-Kristensen, PhD

Department of Spinal Cord Injuries, Copenhagen University

• Professor Fin Biering-Sørensen, MD, PhD

Spinal Cord Injury Centre of Western Denmark, Aarhus University

• Head of Research and Associate professor Helge Kasch, MD, PhD

Department of Orthopedic Surgery, Odense University Hospital

• Consultant orthopaedic surgeon Lars Henrik Frich, MD, PhD

The Nordic Institute of Chiropractic and Clinical Biomechanics, University of Southern Denmark

• Professor and Head of the Research Unit Jan Hartvigsen, PhD

Faculty of Medicine, University of Amsterdam, the Netherlands

• Professor Raoul Engelbert, PhD

Furthermore the project is supported by the PTU Rehabilitation Center, the Danish Sport Organization for Disabled and The Danish Spinal Cord Injuries Association.