Musculoskeletal pain is caused by risk factors for acquiring pain and prognostic factors for the persistence of prolonged pain and is the number one causal reason for restricted participation at work. Many studies have been performed on the reasons for acquiring and the continuance of musculoskeletal pain, however, a comprehensive overview does not exist. Musculoskeletal pain may result in a reduction of the ability to perform physical work.To determine whether a person’s functional capacity is high enough to performwork, standardized functional capacity tests can be executed. One example offunctional capacity tests is to measure lifting capacity. These tests are defined as an evaluation of the capacity of activities that is used to make recommendations for participation in work while considering the person’s body functions and structures, environmental factors, personal factors and health status. How many of the latter components that should be taken into account are unclear. The results of this study can support health care professionals providing care to patients in the field of work participation by making informed decisions during diagnostic procedures.
Objective: Psychophysical lift capacity tests are lifting tests in which the performance, expressed in Newtons, is divided by the perceived exertion, expressed on a Borg scale. The aim of this study was to analyse test-retest reliability of psychophysical lift capacity tests.Subjects: Patients with non-specific chronic low back pain (n=20) and healthy subjects (n=20).Methods: Psychophysical lift capacity tests were assessed during a back school intake at the Centre for Rehabilitation of the University Medical Centre Groningen. Patients on the waiting list and healthy subjects were assessed twice, with a 2-week interval between assessments. Intra-class correlation (ICC) was calculated as a measure of reliability. An ICC ≥0.75 was considered as an acceptable reliability. Limits of agreement as a measure for natural variation were calculated.Results: The psychophysical static and dynamic lift capacity tests showed good reliability (ICC ≥0.75). The limits of agreement are substantial, indicating a considerable natural variation between test-sessions for all psychophysical tests.Conclusion: The psychophysical static lift capacity and dynamic lifting capacity are reliable instruments for patients with non-specific chronic low back pain and healthy subjects. However, a substantial amount of natural variation should be taken into account between 2 test sessions when interpreting the test results clinically.
BACKGROUND: Physical therapists' recommendations to patients to avoid daily physical activity can be influenced by the therapists' kinesiophobic beliefs. Little is known about the amount of influence of a physical therapist's kinesiophobic beliefs on a patient's actual lifting capacity during a lifting test.OBJECTIVE: The objective of this study was to determine the influence of physical therapists' kinesiophobic beliefs on lifting capacity in healthy people.DESIGN: A blinded, cluster-randomized cross-sectional study was performed.METHODS: The participants (n=256; 105 male, 151 female) were physical therapist students who performed a lifting capacity test. Examiners (n=24) were selected from second-year physical therapist students. Participants in group A (n=124) were tested in the presence of an examiner with high scores on the Tampa Scale of Kinesiophobia for health care providers (TSK-HC), and those in group B (n=132) were tested in the presence of an examiner with low scores on the TSK-HC. Mixed-model analyses were performed on lifting capacity to test for possible (interacting) effects.RESULTS: Mean lifting capacity was 32.1 kg (SD=13.6) in group A and 39.6 kg (SD=16.4) in group B. Mixed-model analyses revealed that after controlling for sex, body weight, self-efficacy, and the interaction between the examiners' and participants' kinesiophobic beliefs, the influence of examiners' kinesiophobic beliefs significantly reduced lifting capacity by 14.4 kg in participants with kinesiophobic beliefs and 8.0 kg in those without kinesiophobic beliefs.LIMITATIONS: Generalizability to physical therapists and patients with pain should be studied.CONCLUSIONS: Physical therapists' kinesiophobic beliefs negatively influence lifting capacity of healthy adults. During everyday clinical practice, physical therapists should be aware of the influence of their kinesiophobic beliefs on patients' functional ability.
