M. Steultjens

Proprioception in knee osteoarthritis: a narrative review

OBJECTIVE To give an overview of the literature on knee proprioception in knee osteoarthritis (OA) patients. METHOD A literature search was performed and reviewed using the narrative approach. RESULTS (1) Three presumed functions of knee proprioception have been described in the literature: protection against excessive movements, stabilization during static postures, and coordination of movements. (2) Proprioceptive accuracy can be measured in different ways; correlations between these methods are low. (3) Proprioceptive accuracy in knee OA patients seems to be impaired when compared to age-matched healthy controls. Unilateral knee OA patients may have impaired proprioceptive accuracy in both knees. (4) Causes of impaired proprioceptive accuracy in knee OA remain unknown. (5) There is currently no evidence for a role of impaired proprioceptive accuracy in the onset or progression of radiographic osteoarthritis (ROA). (6) Impaired proprioceptive accuracy could be a risk factor for progression (but not for onset) of both knee pain and activity limitations in knee OA patients. (7) Exercise therapy seems to be effective in improving proprioceptive accuracy in knee OA patients. CONCLUSIONS Recent literature has shown that proprioceptive accuracy may play an important role in knee OA. However, this role needs to be further clarified. A new measurement protocol for knee proprioception needs to be developed. Systematic reviews focusing on the relationship between impaired proprioceptive accuracy, knee pain and activity limitations and on the effect of interventions (in particular exercise therapy) on proprioceptive accuracy in knee OA are required. Future studies focusing on causes of impaired proprioceptive accuracy in knee OA patients are also needed, taking into account that also the non-symptomatic knee may have proprioceptive impairments. Such future studies may also provide knowledge of mechanism underlying the impact of impaired proprioceptive accuracy on knee pain and activity limitations.

A Systematic Review of Instruments Assessing Participation: Challenges in Defining Participation

OBJECTIVES To evaluate: (1) whether instruments which intend to measure participation actually do and (2) how frequently specific aspects and domains of participation are addressed. DATA SOURCES A systematic search was performed in PubMed. STUDY SELECTION Included were patient-reported instruments that primarily aim to measure participation. DATA EXTRACTION The full-text instruments were extracted from the articles or obtained from the authors. Two reviewers independently rated each item of the included instruments as measuring participation (yes, no, or undetermined). For each item, the specific aspect and domain of participation were categorized. DATA SYNTHESIS Included were 103 instruments (2445 items). Of the included items, 619 items concerned participation and 217 concerned undetermined items. In total, 68 instruments contained at least 1 (sub)scale with 50% or more participation or undetermined items. The participation items referred to the participation aspects: participation problems (53%), participation accomplishment (31%), and satisfaction with participation (9%). The domains of the participation items concerned: work/study (27%), social life (27%), general participation (19%), and home (11%). The undetermined items mainly referred to domains about leisure (43%), transport (26%), and shopping (12%). CONCLUSIONS According to our working definition of participation, most instruments that aim to measure participation do so only to a limited extent. These instruments mainly assess aspects of participation problems and participation accomplishment. The domains of participation covered by these instruments primarily include work/study, social life, general participation, home, leisure, transport, and shopping.

Reliability of the KT1000 arthrometer and the Lachman test in patients with an ACL rupture

The underlying study is a cross sectional study on the reliability of the KT1000 arthrometer and the Lachman test to determine the within-session inter-rater reliability and intra-rater reliability of the KT1000 arthrometer and the Lachman test. Twenty patients with a complete tear of the anterior cruciate ligament (ACL) were examined in a single session each. During the assessment, two physical therapists measured the anterior-posterior translation of the knee using both the KT1000 arthrometer and the Lachman test. One examiner performed a repeated measurement of each test for determination of intra-rater reliability. The examiners were blinded to the findings of their colleague. The intraclass correlation coefficient (ICC) was used to describe the degree of reliability of the measurements. High ICCs were found for the intra-rater reliability and the inter-rater reliability of the Lachman test (ICC=1.0 and 0.77). For the KT1000 arthrometer both ICCs were clearly lower (ICC=0.47 and 0.14). The KT1000 arthrometer shows inadequate reliabilities, even when measurements are repeated within a single measurement session. Contrastingly, the Lachman test is a reliable measurement to determine the anterior-posterior laxity of the ACL deficit knee. The results of the present study suggest good within-session intra-rater reliability as well as inter-rater reliability for the Lachman test.

Prevalence and course of forefoot impairments and walking disability in the first eight years of rheumatoid arthritis

OBJECTIVE To evaluate the prevalence and 8-year course of forefoot impairments and walking disability in patients with rheumatoid arthritis (RA). METHODS A total of 848 patients with recent-onset RA from 1995 through the present were included. The patients were assessed annually. Pain and swelling of the metatarsophalangeal (MTP) joints, erosions and joint space narrowing of the MTP joints and first interphalangeal joints, and the Health Assessment Questionnaire walking subscale were analyzed using descriptive and correlational techniques. RESULTS Pain and swelling of > or = 1 MTP joint was present in 70% of patients at baseline, decreasing to approximately 40-50% after 2 years. The forefoot erosion score was > or = 1 in 19% of the patients at baseline, and the prevalence of forefoot erosion increased to approximately 60% after 8 years, during which the mean forefoot erosion score increased from 1.3 to 7.9. At least mild walking disability was present in 57% of patients at baseline, stabilizing at approximately 40% after 1 year. CONCLUSION The prevalence rates for pain and swelling of the MTP joints and walking disability are initially high and then stabilize, but the prevalence and severity of forefoot joint damage increase during an 8-year course of RA. The findings of this study quantitatively emphasize the importance of forefoot involvement in patients with RA.

Structural joint changes, malalignment, and laxity in osteoarthritis of the knee

Objective: To assess the relationship between (i) structural joint changes (i.e. joint space narrowing and osteophyte formation) and laxity and (ii) joint malalignment and laxity in osteoarthritis (OA) of the knee. Methods: A cross‐sectional study was carried out on 35 outpatients with osteoarthritis of the knee. Weight‐bearing radiographs of the knees were used to assess joint space narrowing (JSN) and osteophyte formation. Knee joint laxity was assessed using a device that measures the angular deviation of the knee in the frontal plane (varus–valgus laxity). Malalignment was assessed using a goniometer. All analyses were performed using knees as units of analysis (i.e. 70 knees). Results: The mean laxity of 70 knees was 8.0±4.1°. Knees with minute JSN were significantly more lax than knees with no JSN. There was no significant relationship between osteophyte formation and laxity. Malaligned knees were significantly more lax than aligned knees. Conclusion: Both joint space narrowing and malalignment are related to laxity. These results support the premise that biomechanical factors play a role in the degeneration of the osteoarthritic knee joint.

Identification of phenotypes with different clinical outcomes in knee osteoarthritis: data from the Osteoarthritis Initiative

To identify subgroups or phenotypes of knee osteoarthritis (OA) patients based on similarities of clinically relevant patient characteristics, and to compare clinical outcomes of these phenotypes.

Association of lower muscle strength with self-reported knee instability in osteoarthritis of the knee: Results from the Amsterdam Osteoarthritis Cohort

To determine whether muscle strength, proprioceptive accuracy, and laxity are associated with self‐reported knee instability in a large cohort of knee osteoarthritis (OA) patients, and to investigate whether muscle strength may compensate for impairment in proprioceptive accuracy or laxity, in order to maintain knee stability.

Reproducibility of plantar pressure measurements in patients with chronic arthritis: a comparison of one-step, two-step, and three-step protocols and an estimate of the number of measurements required.

Background: Plantar pressure measurement may be a helpful evaluation tool in patients with foot complaints. Determination of dynamic pressure distribution under the foot may give information regarding gait, progress of disorders, and the effect of treatment. However, for these measurements to have clinical application, reproducibility, consistency, and accuracy must be ascertained. We compared the reproducibility of measurements among one-step, two-step, and three-step protocols for data collection in patients with arthritis. In addition, the number of measurements needed for a consistent average was determined for the protocol that was found to be the most reproducible. Methods: Twenty patients with foot complaints secondary to arthritis participated in the study. Each patient was tested with a pressure platform system using two of the three testing protocols. Reproducibility of contact time and maximal peak pressure were assessed. Intraclass Correlation Coefficients (ICC) were calculated for measurement results among protocols. In stage two of the study, the number of measurements needed for a consistent average was determined by calculating the first three measurements, the first five measurements, and then all seven measurements for both feet. ICC of three, five, and seven measurements were compared. The two-step protocol (13 patients), which was found in stage one of the study to be the most reproducible, was used for this determination. Results: Reproducibility was found to be reasonable or good for all three measurement protocols. The mean values of contact time for the one-step protocol were found to be higher than the mean values of contact time for the two-step or three-step protocols in both feet. The differences between the one-step and three-step protocols were statistically significant for the left foot only. The mean peak pressure did not show statistically-significant differences among the three protocols. The one-step and three-step protocols were not used for stage two of the study. Using the two-step protocol, three measurements were found to be sufficient for obtaining a consistent average. Conclusions: The results of our study indicated that the one-step, two-step, and three-step protocols of collecting plantar pressure measurements in patients with foot complaints secondary to chronic arthritis were all similar. However, the use of the two-step protocol is recommended over the one-step and three-step protocols; the one-step protocol produced a longer stance phase that did not resemble normal walking and when comparing the two-step and three-step protocols, the two-step protocol was less time consuming and less strenuous for patients with painful feet.

Three trajectories of activity limitations in early symptomatic knee osteoarthritis: a 5-year follow-up study

Objectives Knee osteoarthritis (OA) is a leading cause of activity limitations. The knee OA population is likely to consist of subgroups. The aim of the present study was to identify homogeneous subgroups with distinct trajectories of activity limitations in patients with early symptomatic knee OA and to describe characteristics of these subgroups. Methods Follow-up data over a period of 5 years of 697 participants with early symptomatic knee OA from the Cohort Hip and Cohort Knee (CHECK) were used. Activity limitations were measured yearly with the Western Ontario and McMaster Universities Osteoarthritis Index. Latent class growth analyses identified homogeneous subgroups with distinct trajectories of activity limitations. Multivariable regression analyses examined differences in characteristics between the subgroups. Results Three subgroups were identified. Participants in Subgroup 1 (‘good outcome’; n=330) developed or displayed slight activity limitations over time. Participants in Subgroup 2 (‘moderate outcome’; n=257) developed or displayed moderate activity limitations over time. Participants in subgroup 3 (‘poor outcome’; n=110) developed or displayed severe activity limitations over time. Compared with the ‘good outcome’ subgroup, the ‘moderate outcome’ and ‘poor outcome’ subgroups were characterised by: younger age, higher body mass index, greater pain, bony tenderness, reduced knee flexion, hip pain, osteophytosis, ≥3 comorbidities, lower vitality or avoidance of activities. Conclusions Based on the 5-year course of activity limitations, we identified homogeneous subgroups of knee OA patients with good, moderate or poor outcome. Characteristics of these subgroups were consistent with existing knowledge on prognostic factors regarding activity limitations, which supports the validity of this classification.

A systematic review of instruments measuring foot function, foot pain, and foot-related disability in patients with rheumatoid arthritis

OBJECTIVE To compose an inventory of instruments that have been described to measure foot function (i.e., pressure and/or gait parameters), foot pain, and foot-related disability in rheumatoid arthritis (RA), and to investigate the clinimetric quality of these measures. METHODS A systematic search was conducted in Medline, CINAHL, EMBase, and Sportdiscus. Standardized criteria, extended with levels of evidence, were applied to assess the quality of the clinimetric studies and the properties (i.e., reliability, validity, and responsiveness) of the described instruments. RESULTS A variety of measurement instruments were identified. Only 16 instruments have been studied for their measurement properties in RA patients: 7 for assessing foot function, 3 for measuring foot-related disability, and 6 for measuring both foot pain and foot-related disability. Thirteen instruments were rated for reliability, of which 10 were rated positively on different levels of evidence. No positive rating for absolute measurement error was applicable for any of the tests. Internal consistency was reported for 7 instruments; 3 assigned a positive rating. For 2 instruments, Rasch analysis was used to assess the methodologic quality. A positive rating was reported for goodness-of-fit only, not for item calibration. Seven instruments were rated for construct validity, and 3 assigned a positive rating. Only 2 instruments were rated positively for responsiveness. CONCLUSION This review offers a basis for choosing the most appropriate instruments for measuring foot function, foot pain, and foot-related disability in RA patients, both for clinical practice and for research. Further research on the quality of these measures is urgently needed.