Physical strain

“The challenge is Healthy Ageing: growing older in a healthy and active way. Maintaining good health well beyond pension age would greatly enhance quality

of life and well-being, as well as labour participation, informal care capacity and other significant contributions to society. However, new knowledge is required

about the influence of these factors, and how they interact with one another.”

Subject of this thesis was one of the dominant health issues in persons with a spinal cord injury, namely shoulder pain and limitations in shoulder range of motion and its consequences on performance of activities and participation.

A spinal cord injury results in muscle weakness or paralysis, loss of sensation and loss of autonomic function below the level of the lesion. After a spinal cord injury, approximately 80% of the persons remain wheelchair-dependent and rely on their upper extremities for mobility and daily tasks. As such, it is not surprising that shoulder pain and limitations in shoulder range of motion are common among persons with spinal cord injury. The mean prevalence of shoulder was found to be approximately 50% during both the acute and chronic phase after spinal cord injury. The mean prevalence of range of motion limitations was approximately 30% and 40%, respectively. Although it has been suggested that shoulder pain might negatively affect activities and participation, as well as quality of life, the association of passive shoulder range of motion limitations and shoulder pain with activities and participation is only scarcely studied and the literature shows conflicting results.

Therefore the (mechanism of the) development of shoulder problems and their course over time in persons with spinal cord injury were unclear at the start of the study. To improve goal setting and to optimize intervention programs in in- and outpatient rehabilitation and follow-up care, the aim of the present thesis was: 1) to gain understanding in structural changes, prevalence and the course of shoulder problems (pain and range of motion) over time and, 2) to study the complex association between aspects of shoulder structure, shoulder function and activities and participation using the International Classification of Functioning, Disability and Health as a framework.

In chapter 1 an overview of the context of the thesis was given. A short description of the health condition ‘spinal cord injury’, its epidemiology has been presented. Afterwards, an overview of the most important secondary health conditions in persons with spinal cord injury was presented. Third, the consequences of a spinal cord injury on functioning were explained, introducing the bio-psychosocial model of the International Classification of Functioning, Disability and Health. Following was a description of the functional anatomy of the shoulder complex, the current understanding of shoulder impairment in persons with a spinal cord injury and the association of shoulder pain and shoulder range of motion with activities and participation in spinal cord injury are described. After a short description of medical and rehabilitation care in the Netherlands and Switzerland, the research context of this thesis was described, namely the Dutch prospective cohort study ‘Restoration of mobility in spinal cord injury rehabilitation’, also called ‘the Umbrella project’, and its follow-up study the ‘Spinal cord injury QUality of life Evaluation (SPIQUE)’ project, the Swiss Paraplegic Research and the Swiss Paraplegic Centre. Finally, a detailed outline with aim, research objectives and research questions of this thesis was presented.

In chapter 2 we have presented a study performed at the Swiss Paraplegic Research and Swiss Paraplegic Centre, in which we have compared prevalence, severity and risk of acromioclavicular joint arthrosis in persons presenting with shoulder pain with and without a spinal cord injury. We performed a retrospective analysis of medical records of 68 persons with spinal cord injury and 105 able-bodied persons with shoulder pain and evaluated magnetic resonance images collected in the outpatient orthopaedics clinic. We found that the overall prevalence of acromioclavicular joint arthrosis was 98% for persons with spinal cord injury and 92% for able-bodied persons. In both groups, acromioclavicular joint arthrosis was frequently accompanied by diagnosis of rotator cuff tears and biceps tendon ruptures. Sensitivity of clinical testing was found to be low in spinal cord injury (0.31) as well as in able-bodied persons (0.23) with shoulder pain. The odds of increasingly severe arthrosis was nearly 4 times higher in persons with spinal cord injury compared to able-bodied persons (p=0.0001). The analysis of arthrosis severity in the spinal cord injury-group revealed, after controlling for the effects of sex and age, a weak association with time since injury and no association with level or completeness of the lesion.

We concluded that persons with spinal cord injury and shoulder pain showed similar prevalence, yet more advanced acromioclavicular joint arthrosis than able-bodied persons with shoulder pain. This is likely caused by the high burden on the shoulder from manual wheelchair propulsion and other wheelchair-related activities such as transfers and weight relief maneuvers. Since early diagnosis of arthrosis is a prerequisite for the initiation of successful conservative interventions of shoulder deterioration, we recommend routine assessment of shoulder status including diagnostic imaging during check-ups.

Although shoulder pain is a problem in the majority of persons with spinal cord injury, so far no studies have empirically identified longitudinal patterns (trajectories) of musculoskeletal shoulder pain after spinal cord injury. Therefore the aim of chapter 3 was: 1) to identify distinct trajectories of musculoskeletal shoulder pain in persons with spinal cord injury, and 2) to determine possible predictors of these trajectories.

We studied a multicenter prospective cohort of 225 newly injured persons with spinal cord injury in the Netherlands (participants of the Umbrella and SPIQUE studies). Shoulder pain was assessed on five occasions: at start of active rehabilitation, three months later, at discharge, at one year and five years after discharge. Latent class growth mixture modeling was used to identify the distinct shoulder pain trajectories.

We identified three distinct shoulder pain trajectories: a ‘No or Low pain’ trajectory (64%), a ‘High pain’ (30%) trajectory, and a trajectory with a ‘Decrease of pain’ (6%). Compared with the ‘No or Low pain’ pain trajectory, the ‘High pain’ trajectory consisted of more persons with tetraplegia, shoulder pain before injury, limited shoulder range of motion, lower manual muscle test scores, or more spasticity at start of active rehabilitation. Multivariate logistic regression analysis showed two significant predictors for the ‘High pain’ trajectory (as compared with the ‘No or Low pain’ trajectory): having a tetraplegia (odds ratio (OR) = 3.2; p=0.002) and having limited shoulder range of motion (OR=2.8; p=0.007). Surprisingly, we did not find an ‘Increase of pain’ trajectory. One of the reasons might be that an increase of pain due to degenerative causes may present at later age and after longer time since injury. Therefore, a study with longer follow-up is needed.

Since literature regarding prevalence and course over time of shoulder range of motion is scarce, we have investigated the prevalence and course of passive shoulder range of motion in people with spinal cord injury and analysed the relationships between shoulder range of motion limitations and personal and lesion characteristics. The results of this study were presented in chapter 4.

A total of 199 participants with a new spinal cord injury were included in the Dutch multicenter Umbrella study. We assessed shoulder range of motion at the start of active rehabilitation, three months later, at discharge and one year after discharge. We found a limited shoulder range of motion (≥10°) in up to 70% (95% CI: 57–81) of the subjects with tetraplegia and in 29% (95% CI: 20–38) of those with paraplegia during or in the first year after inpatient rehabilitation. Shoulder flexion was mostly affected. Up to 26% (95% CI: 20–37) of the participants had bilateral shoulder range of motion limitation. We found that a limited shoulder range of motion is common following spinal cord injury and that tetraplegia, increased age, spasticity of elbow extensors, longer duration between injury and start of active rehabilitation and presence of shoulder pain increased the risk of limited shoulder range of motion.

Activities and participation: associations with shoulder range of motionand shoulder pain

In chapter 5 we have described the results of the study on the relation between limited shoulder range of motion at discharge in 146 participants with spinal cord injury on the performance of activities, wheeling performance, transfers and participation one year later. We assessed shoulder range of motion at discharge from first rehabilitation and assessed the Functional Independence Measure (FIM)-Motor Score, the ability to transfer, the Wheelchair Skills Test (WST) and the Physical Activity Scale for Individuals with Physical Disabilities (PASIPD) one year later. Possible confounding factors were age, gender, level and completeness of injury, time since injury and shoulder pain. Data were analysed for the total group (both paraplegia and tetraplegia) and for the subgroup of persons with tetraplegia. We found that participants with limited shoulder range of motion at discharge had a worse independence on FIM-Motor Score and were less likely (total group 5 times, participants with tetraplegia 10 times less likely) to perform an independent transfer one year later. In the total group, participants with limited shoulder range of motion needed more time to complete a 15 meter sprint and figure-of-eight in the wheelchair. In both groups no significant associations with the level of physical activity (PASIPD) were found.

In chapter 6 we have presented the results of the study analyzing the association of musculoskeletal shoulder pain and limitations in shoulder range of motion at discharge from first rehabilitation and activities and participation five years later in 138 participants of the Umbrella and SPIQUE studies. The main outcome measures used in this study were Peak exercise performance, WST, FIM-Motor Score, ability to transfer, PASIPD, Mobility Range and Social Behavior scales of the Sickness Impact Profile 68 (SIPSOC) and employment status.

We found that shoulder range of motion limitations, but not shoulder pain, was bivariately associated with all but one outcomes at 5 years. After correcting for confounders (personal and lesion characteristics) shoulder range of motion limitation at discharge showed to be negatively associated with the ability to transfer independently FIM-Motor Score, and return to work 5 years later. No significant associations were found with Peak exercise performance, performance of time of the WST, the PASIPD and SIPSOC.

Finally, in chapter 7 the main findings of the thesis were summarized and discussed in the context of the scientific literature. Subsequently, we have discussed some of the methodological considerations related to the study design and its implications for the interpretation and generalizability of the study results. We have given, based on our results, available literature and clinical experience, recommendations for future research, like performing studies with a comprehensive approach, including kinematics and diagnostic imaging, the use of uniform outcome measures and discussed the role and content of intervention studies.

Finally, based on our results, available literature and clinical experience, we have given recommendations for clinical practice. In the acute phase optimal shoulder positioning and early (passive and active) mobilization of the shoulder joint should be warranted. The training of the upper extremities and how to use the shoulder during tasks should be focus during rehabilitation. Patients should be (made) aware that training of the upper extremities is a lifelong challenge and should be educated how to best train and use their shoulders in daily life and prevent overuse injuries. Optimizing wheelchair design, adjusted to the individual needs of the patient, with optimizing the ergonomics and mechanics, tire type and tire pressure should be warranted in each patient with SCI. Choosing an alternative mode for mobility that is less straining for the shoulder, like hand-cycling, should be considered for all patients. Applying assistive devices for transfers and adaptations to the car for carrying the wheelchair in the car should be applied where needed. We have recommended to establish a life-long comprehensive follow-up of shoulder problems in persons with spinal cord injury, including medical anamneses and clinical examination and diagnostic imaging, but also including observation and kinematic analysis of wheelchair skills and performance and the assessment of current use of and need for adaptive devices like the wheelchair. This comprehensive assessment of shoulder function starting shortly after SCI and across the life-span is needed to diagnose shoulder problems at an early stage in order to intervene successfully and try to maintain healthy ageing in persons with spinal cord injury.

Contact address

Sonja de Groot / Lucas van der Woude

Center for Human Movement Sciences

University Medical Center Groningen

University of Groningen

Antonius Deusinglaan 1

9713AV Groningen,

The Netherlands