PROMIS Physical Function short forms display item- and scale-level characteristics at least as good as the Roland Morris Disability Questionnaire in patients with chronic low back pain

OBJECTIVE: To compare dimensionality, item-level characteristics, scale-level reliability and construct validity of PROMIS® Physical Function short forms (PROMIS-PF) and 24-item Roland Morris Disability Questionnaire (RMDQ-24) in patients with chronic low back pain (LBP). DESIGN: Cross-sectional study. SETTING: Secondary care center for rehabilitation and rheumatology. PARTICIPANTS: Patients with non-specific LBP ≥ 3 months (n = 768). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Dutch versions of the 4-, 6-, 8-, 10- and 20-item PROMIS-PF, and of the RMDQ-24. RESULTS: Mean age was 49 years (±13), 77% female, 54% displayed pain for more than 5 years. PROMIS-PF-6, PROMIS-PF-8 and RMDQ-24 exhibited sufficient unidimensionality (confirmatory factor analysis: CFI >0.950, TLI >0.950 and RMSEA 0.001). Two-parameter item response theory models found two items with low discrimination for RMDQ-24. All other instruments had adequate fit statistics and item parameters. PROMIS-PF-20 displayed the best scale-level reliability. Construct validity was sufficient for all instruments as all hypotheses on expected correlations with other instruments, and differences between relevant subgroups, were met. CONCLUSIONS: PROMIS-PF-6, PROMIS-PF-8 and RMDQ-24 exhibited better unidimensionality, whereas PROMIS-PF-4, PROMIS-PF-6 PROMIS-PF-8 and PROMIS-PF-10 showed superior item-level characteristics. PROMIS-PF-20 was the instrument with the best scale-level reliability. This study warrants assessment of other measurement properties of PROMIS-PF short forms in comparison to disease-specific physical functioning instruments in LBP

Improving the Action Research Arm test: a unidimensional hierarchical scale

The Action Research Arm (ARA) test is a performance test of upper extremity motor function which consists of 19 items divided into four hierarchical subtests. This multidimensionality has not yet been tested empirically. To investigate the dimensionality of the ARA test. Cross-sectional study involving a sample of 63 chronic stroke patients. A Mokken scale analysis was performed. The Mokken scale analysis revealed one strong unidimensional scale containing all 19 items, of which the scalability coefficient H was 0.79, while H per item ranged from 0.69 to 0.86. The reliability coefficient rho equalled 0.98, indicating a very high internal consistency. A subset of 15 out of 19 items showed an invariant hierarchical item-ordering. The ARA test is a unidimensional scale. The use of subtests, as proposed in the original description of the instrument, is not supported by the present findings. The 15-item scale presented here can be used for adaptive testing, i.e. using only a selected subset of items based on prior knowledge about the patient's abilities, thus minimizing testing tim

Biomechanical factors and physical examination findings in osteoarthritis of the knee: associations with tissue abnormalities assessed by conventional radiography and high resolution 3.0 Tesla magnetic resonance imaging

INTRODUCTION: We aimed to explore the associations between knee osteoarthritis (OA)-related tissue abnormalities assessed by conventional radiography (CR) and by high-resolution 3.0 Tesla magnetic resonance imaging (MRI), as well as biomechanical factors and findings from physical examination in patients with knee OA. METHODS: This was an explorative cross-sectional study of 105 patients with knee OA. Index knees were imaged using CR and MRI. Multiple features from CR and MRI (cartilage, osteophytes, bone marrow lesions, effusion and synovitis) were related to biomechanical factors (quadriceps and hamstrings muscle strength, proprioceptive accuracy and varus-valgus laxity) and physical examination findings (bony tenderness, crepitus, bony enlargement and palpable warmth), using multivariable regression analyses. RESULTS: Quadriceps weakness was associated with cartilage integrity, effusion, synovitis (all detected by MRI) and CR-detected joint space narrowing. Knee joint laxity was associated with MRI-detected cartilage integrity, CR-detected joint space narrowing and osteophyte formation. Multiple tissue abnormalities including cartilage integrity, osteophytes and effusion, but only those detected by MRI, were found to be associated with physical examination findings such as crepitus. CONCLUSION: We observed clinically relevant findings, including a significant association between quadriceps weakness and both effusion and synovitis, detected by MRI. Inflammation was detected in over one-third of the participants, emphasizing the inflammatory component of OA and a possible important role for anti-inflammatory therapies in knee OA. In general, OA-related tissue abnormalities of the knee, even those detected by MRI, were found to be discordant with biomechanical and physical examination features

Perceived independence and limitations in rising and sitting down after rehabilitation for a lower-limb amputation

Objective: To study perceived independence in rising and perceived limitations in rising and sitting down in persons after a lower-limb amputation and the relationship of these perceptions with personal and clinical characteristics. Design: Cross-sectional study. Subjects/patients: Persons with a lower-limb amputation wearing a prosthesis (n=172). Methods: Perceived independence in rising was assessed with the Locomotor Capabilities Index. Limitations in rising and sitting down were assessed with the Questionnaire Rising and Sitting down. Multivariate logistic and linear regression analyses, respectively, were used to investigate the associations between independence and limitations in rising and sitting down, and personal and clinical characteristics. Results: Of the participants, 91% and 47% perceived independence in rising from a chair and rising from the floor, respectively. Older participants and women perceived less independence in rising. Participants perceived marked limitations in rising and sitting down, with those rehabilitated in a nursing home perceiving more limitations. Conclusion: After a lower-limb amputation, most persons wearing a prosthesis are able to rise independently from a chair, but many perceive decreased independence in other forms of rising, especially older participants and women. Participants, especially those rehabilitated in a nursing home, perceive considerable limitations in rising and sitting down. However, in those patients rehabilitated in a nursing home these limitations may be due to indication bias

Prevalence of comorbidity and its association with demographic and clinical characteristics in persons wearing a prosthesis after a lower-limb amputation

Objective: To describe the prevalence of comorbidity and its relationship with demographic and clinical characteristics in persons wearing a prosthesis after lower-limb amputation. Design: Cross-sectional study. Subjects/patients: Persons wearing a prosthesis after lower-limb amputation (n = 171; mean age 65 years (standard deviation 12); 72% men) at the end of outpatient rehabilitation treatment. Methods: Comorbidity was assessed with the Functional Comorbidity Index: a list of 18 items addressing the presence of specific comorbid conditions impacting on functional status. Comorbidities in medical records were assessed independently by 2 assessors. Associations with demographic and clinical characteristics were analysed using linear or logistic regression. Results: The median (interquartile range) number of comorbidities was 3 (2; 4). Three or more comorbidities were present in 103 of 171 (60%) participants. Diabetes was present in 71 (41%), cardiac disease in 60 (35%), and lumbago/degenerative disc disease in 39 (23%) participants. The prevalence of comorbidities was higher in women and those with vascular cause of amputation. Conclusion: There is a high prevalence of comorbidity at the end of outpatient rehabilitation treatment in persons wearing a prosthesis after a lower-limb amputation, especially in women and those with vascular cause of amputation

Decreased Pain and Improved Dynamic Knee Instability Mediate the Beneficial Effect of Wearing a Soft Knee Brace on Activity Limitations in Patients With Knee Osteoarthritis

OBJECTIVE: To evaluate whether improvement of proprioception, pain or dynamic knee instability mediate the effect of wearing a soft knee brace on activity limitations in persons with knee osteoarthritis (OA). METHODS: Exploratory analysis from 44 participants with knee OA and self-reported knee instability in a laboratory trial evaluating the effect of wearing a commercially available soft knee brace. Activity limitations were assessed with the 10-meter walk test and the Get up and Go test. Knee joint proprioception was assessed by an active joint position sense test; pain was assessed with the Numeric Rating Scale (NRS); pressure pain threshold (PPT) was assessed with a hand-held pressure algometer; dynamic knee instability was expressed by the Perturbation Response, i.e. a measure reflecting a deviation in mean knee varus-valgus angle after a controlled mechanical perturbation on a treadmill, with respect to level walking. Mediation analysis was conducted with the product of coefficients approach. Confidence intervals were calculated with a bootstrap procedure. RESULTS: A decrease of pain (NRS) and a decrease of dynamic knee instability mediated the effect of wearing a soft knee brace on reduction of activity limitations (p < 0.05), while changes of proprioception and PPT did not mediate this effect (p > 0.05). CONCLUSION: This study shows that decreased pain and reduced dynamic knee instability are pathways via which wearing a soft knee brace decreased activity limitations in persons with knee OA. This article is protected by copyright. All rights reserved

The association between reduced knee joint proprioception and medial meniscal abnormalities using MRI in knee osteoarthritis: results from the Amsterdam osteoarthritis cohort.

BACKGROUND: Osteoarthritis (OA) of the knee is characterized by pain and activity limitations. In knee OA, proprioceptive accuracy is reduced and might be associated with pain and activity limitations. Although causes of reduced proprioceptive accuracy are divergent, medial meniscal abnormalities, which are highly prevalent in knee OA, have been suggested to play an important role. No study has focussed on the association between proprioceptive accuracy and meniscal abnormalities in knee OA. OBJECTIVE: To explore the association between reduced proprioceptive accuracy and medial meniscal abnormalities in a clinical sample of knee OA subjects. METHODS: Cross-sectional study in 105 subjects with knee OA. Knee proprioceptive accuracy was assessed by determining the joint motion detection threshold in the knee extension direction. The knee was imaged with a 3.0 T magnetic resonance (MR) scanner. Number of regions with medial meniscal abnormalities and the extent of abnormality in the anterior and posterior horn and body were scored according to the Boston-Leeds Osteoarthritis Knee Score (BLOKS) method. Multiple regression analyzes were used to examine whether reduced proprioceptive accuracy was associated with medial meniscal abnormalities in knee OA subjects. RESULTS: Mean proprioceptive accuracy was 2.9degree + 1.9degree. Magnetic resonance imaging (MRI)-detected medial meniscal abnormalities were found in the anterior horn (78%), body (80%) and posterior horn (90%). Reduced proprioceptive accuracy was associated with both the number of regions with meniscal abnormalities (P < 0.01) and the extent of abnormality (P = 0.02). These associations were not confounded by muscle strength, joint laxity, pain, age, gender, body mass index (BMI) and duration of knee complaints. CONCLUSION: This is the first study showing that reduced proprioceptive accuracy is associated with medial meniscal abnormalities in knee OA. The study highlights the importance of meniscal abnormalities in understanding reduced proprioceptive accuracy in persons with knee OA. Copyright 2013 Osteoarthritis Research Society International. All rights reserve

The immediate effect of a soft knee brace on pain, activity limitations, self-reported knee instability, and self-reported knee confidence in patients with knee osteoarthritis

Background: We aimed to (i) evaluate the immediate effect of a soft knee brace on pain, activity limitations, self-reported knee instability, and self-reported knee confidence, and (ii) to assess the difference in effect between a non-tight and a tight soft brace in patients with knee osteoarthritis (OA). Methods: Forty-four patients with knee OA and self-reported knee instability participated in the single-session, laboratory, experimental study. A within-subject design was used, comparing a soft brace with no brace, and comparing a non-tight with a tight soft brace. The outcome measures were pain, self-reported knee instability and knee confidence during level and perturbed walking on the treadmill and activity limitations (10-m walk test and the get up and go (GUG) test). Linear mixed-effect model analysis for continuous outcomes and logistic generalized estimating equations for categorical outcomes were used to evaluate the effect of wearing a soft brace. Results: Wearing a soft brace significantly reduced pain during level walking (B - 0.60, P = 0.001) and perturbed walking (B - 0.80, P < 0.001), reduced the time to complete the 10-m walk (B - 0.23, P < 0.001) and the GUG tests (B - 0.23, P = 0.004), reduced self-reported knee instability during level walking (OR 0.41, P = 0.002) and perturbed walking (OR 0.36, P < 0.001), and reduced lack of confidence in the knees during level walking (OR 0.45, P < 0.001) and perturbed walking (OR 0.56, P < 0.001), compared with not wearing a soft brace. There was no difference in effects between a non-tight and tight brace, except for the 10-m walk test. Wearing a tight brace significantly reduced the time to complete the 10-m walk test in comparison with wearing a non-tight brace (B - 0.11, P = 0.03). Conclusion: The results of this study indicate that a soft brace is an efficacious intervention targeting pain, activity limitations, self-reported knee instability, and knee confidence in the immediate term in patients with knee OA. Further studies are needed evaluating the mode of action based on exerted pressure, and on the generalization to functioning in daily life. Trial registration: trialregister.nl, NTR6363. Retrospectively registered on 15 May 2017