Norma J. MacIntyre

Patellofemoral Joint Kinematics in Individuals with and without Patellofemoral Pain Syndrome

BACKGROUND Patellofemoral pain syndrome is a prevalent condition in young people. While it is widely believed that abnormal patellar tracking plays a role in the development of patellofemoral pain syndrome, this link has not been established. The purpose of this cross-sectional case-control study was to test the hypothesis that patterns of patellar spin, tilt, and lateral translation make it possible to distinguish individuals with patellofemoral pain syndrome and clinical evidence of patellar malalignment from those with patellofemoral pain syndrome and no clinical evidence of malalignment and from individuals with no knee problems. METHODS Three-dimensional patellofemoral joint kinematics in one knee of each of sixty volunteers (twenty in each group described above) were assessed with use of a new, validated magnetic resonance imaging-based method. Static low-resolution scans of the loaded knee were acquired at five different angles of knee flexion (ranging between -4 degrees and 60 degrees). High-resolution geometric models of the patella, femur, and tibia and associated coordinate axes were registered to the bone positions on the low-resolution scans to determine the patellar motion as a function of knee flexion angle. Hierarchical modeling was used to identify group differences in patterns of patellar spin, tilt, and lateral translation. RESULTS No differences in the overall pattern of patellar motion were observed among groups (p>0.08 for all global maximum likelihood ratio tests). Features of patellar spin and tilt patterns varied greatly between subjects across all three groups, and no significant group differences were detected. At 19 degrees of knee flexion, the patellae in the group with patellofemoral pain and clinical evidence of malalignment were positioned an average of 2.25 mm more laterally than the patellae in the control group, and this difference was marginally significant (p=0.049). Other features of the pattern of lateral translation did not differ, and large overlaps in values were observed across all groups. CONCLUSIONS It cannot be determined from our cross-sectional study whether the more lateral position of the patella in the group with clinical evidence of malalignment preceded or followed the onset of symptoms. It is clear from the data that an individual with patellofemoral pain syndrome cannot be distinguished from a control subject by examining patterns of spin, tilt, or lateral translation of the patella, even when clinical evidence of mechanical abnormality was observed.

Too Fit To Fracture: exercise recommendations for individuals with osteoporosis or osteoporotic vertebral fracture

SummaryA consensus process was conducted to develop exercise recommendations for individuals with osteoporosis or vertebral fractures. A multicomponent exercise program that includes balance and resistance training is recommended.IntroductionThe aim was to develop consensus on exercise recommendations for older adults: (1) with osteoporosis and (2) with osteoporotic vertebral fracture(s).MethodsThe Grading of Recommendations Assessment, Development, and Evaluation method was used to evaluate the quality of evidence and develop recommendations. Outcomes important for decision making were nominated by an expert panel and patient advocates. They included falls, fractures, bone mineral density (BMD), and adverse events for individuals with osteoporosis/vertebral fractures, and pain, quality of life, and function for those with vertebral fracture. Meta-analyses evaluating the effects of exercise on the outcomes were reviewed. Observational studies or clinical trials were reviewed when meta-analyses were not available. Quality ratings were generated, and informed the recommendations.ResultsThe outcome for which evidence is strongest is falls. Point estimates of the effects of exercise on falls, fractures, and BMD vary according to exercise type. There is not enough evidence to quantify the risks of exercise in those with osteoporosis or vertebral fracture. Few trials of exercise exist in those with vertebral fracture. The exercise recommendations for exercise in individuals with osteoporosis or osteoporotic vertebral fracture are conditional. The panel strongly recommends a multicomponent exercise program including resistance and balance training for individuals with osteoporosis or osteoporotic vertebral fracture. The panel recommends that older adults with osteoporosis or vertebral fracture do not engage in aerobic training to the exclusion of resistance or balance training.ConclusionsThe consensus of our international panel is that exercise is recommended for older adults with osteoporosis or vertebral fracture, but our recommendations are conditional.

Quantifying Self-Report Measures' Overestimation of Mobility Scores Postarthroplasty

Background Self-reports of function may systematically overestimate the ability of patients to move around postarthroplasty. Objective The purpose of this study was to estimate the magnitude of systematic differences in Lower Extremity Functional Scale (LEFS) and Western Ontario and McMaster Universities Osteoarthritis Index physical function subscale (WOMAC-PF) scores before and after primary total knee arthroplasty (TKA) or total hip arthroplasty (THA) by referencing the values to Six-Minute Walk Test (6MWT) distances and Timed “Up & Go” Test (TUG) times. Design This study was a secondary analysis of data from a prospective cohort study. Methods The LEFS, WOMAC, 6MWT, and TUG were administered to 85 patients prearthroplasty and once at 9 to 13 weeks postarthroplasty. Regression analysis was applied using a robust error term for clustered data. With the self-report measures as dependent variables and performance measures, occasion (prearthroplasty or postarthroplasty), and performance measure-by-occasion as independent variables, 3 propositions were examined: (1) the relationship between self-report and performance measures is identical prearthroplasty and postarthroplasty (ie, regression lines are coincident); (2) the relationship differs between occasions, but is consistent (ie, regression lines are parallel); (3) the relationship is not consistent (ie, the regression lines are not parallel). Results For all analyses, the results supported the second proposition (ie, the relationship differed between occasions, but was consistent). The systematic differences varied by location of arthroplasty, but were similar for both performance tests. For the LEFS, the difference was approximately 11 points for patients who received TKA and 13 points for patients who received THA. For the WOMAC-PF, the difference was approximately 12 points for patients who received TKA and 19 points for patients who received THA. These differences exceed the minimal clinically important change for an individual patient. Limitations The findings are specific to 9 to 13 weeks postarthroplasty. Conclusion Dependence on scores of self-report measures alone, without knowledge of the magnitude of the identified systematic differences, will result in overestimating the ability of patients to move around postarthroplasty.

Efficacy of ultrasound therapy for the management of knee osteoarthritis: a systematic review with meta-analysis

OBJECTIVE To assess the efficacy of ultrasound therapy (US) for decreasing pain and improving physical function, patient-perception of disease severity, and cartilage repair in people with knee osteoarthritis (OA). METHODS We conducted a systematic review (to February 2009) without language limits in MEDLINE, EMBASE, Cochrane Library, LILACS, MEDCARIB, CINAHL, PEDro, SPORT-discus, REHABDATA, and World Health Organization Clinical Trial Registry. We included randomized controlled trials of people with knee OA comparing the outcomes of interest for those receiving US with those receiving no US. Two reviewers independently selected studies, extracted relevant data and assessed quality. Pooled analyses were conducted using inverse-variance random effects models. MAIN RESULTS Six small trials (378 patients) were included. US improves pain [Standardized Mean Difference (SMD) (95% confidence interval (CI))=-0.49 (-0.79, -0.18), P=0.002], and tends to improve self-reported physical function [SMD (CI)=-0.54 (-1.19, 0.12), P=0.11] along with walking performance [SMD (CI)=0.81 (-0.09, 1.72), P=0.08]. Results from two trials (128 patients), conducted by the same group, show a positive effect of US on pain [SMD (CI)=-0.77 (-1.15, -0.39), P<0.001], self-reported physical function [SMD (CI)=-1.25 (-1.69, -0.81), P<0.001], and walking performance [SMD (CI)=1.47 (1.06, 1.88), P<0.001] at 10 months after the intervention concluded. Heterogeneity observed between studies regarding the effect of US on pain was explained by US dose, mode and intensity. The quality of evidence supporting these effect estimates was rated as low. CONCLUSIONS US could be efficacious for decreasing pain and may improve physical function in patients with knee OA. The findings of this review should be confirmed using methodologically rigorous and adequately powered clinical trials.

Relationship of intermuscular fat volume in the thigh with knee extensor strength and physical performance in women at risk of or with knee osteoarthritis

To determine the extent to which thigh intermuscular fat (IMF) and quadriceps muscle (QM) volumes explained variance in knee extensor strength and physical performance in women with radiographic knee osteoarthritis (ROA) and without.

Effect of Low-Intensity Pulsed Ultrasound on the Cartilage Repair in People With Mild to Moderate Knee Osteoarthritis: A Double-Blinded, Randomized, Placebo-Controlled Pilot Study

OBJECTIVE To determine the feasibility of conducting a randomized controlled trial assessing the effect of low-intensity pulsed ultrasound (US) therapy on cartilage repair in patients with mild to moderate knee osteoarthritis (OA). DESIGN Pilot, double-blinded, randomized placebo-controlled trial with 2-months follow-up. SETTING Rehabilitation research facility. PARTICIPANTS Adults (N=27; ≥45y) with grades 1 or 2 of medial joint space narrowing (Osteoarthritis Research Society International atlas) due to knee OA were randomly allocated to receive active (n=14) or sham (n=13) US therapy. Four participants withdrew for personal reasons. INTERVENTIONS Twenty-four sessions of active (20% duty cycle, 1MHz, average temporal intensity: 0.2W/cm(2), therapeutic dose: 112.5J/cm(2)) or sham (no sound-head crystal) US therapy. MAIN OUTCOME MEASURES Success of recruitment and adherence rates were established by a priori criteria. Effect on cartilage repair was assessed by measuring cartilage volume and thickness and scoring cartilage injury, subchondral cyst formation, and bone marrow lesions on magnetic resonance images. RESULTS Patient recruitment and adherence rates were successful. No significant age-adjusted differences were seen between groups in the cartilage repair outcomes. Age-adjusted analyses, including only subjects who attended 20 sessions or more, showed an increase in medial tibia cartilage thickness in the active US therapy group (90μm; 95% confidence interval, 1-200; P=.05). CONCLUSIONS Conducting a randomized controlled trial to assess the effects of US therapy on the cartilage repair in people with mild to moderate knee OA is feasible. However, further pilot studies are needed to determine the optimal US dose and application parameters before designing a full trial.

Repeatability of a novel technique for in vivo measurement of three-dimensional patellar tracking using magnetic resonance imaging.

To determine the repeatability of a novel noninvasive MRI‐based technique for measuring patellofemoral kinematics in vivo.

Relationship Between Varus-Valgus Alignment and Patellar Kinematics in Individuals with Knee Osteoarthritis

BACKGROUND Abnormal varus-valgus alignment is a risk factor for patellofemoral osteoarthritis, but tibiofemoral alignment alone does not explain compartmental patellofemoral osteoarthritis progression. Other mechanical factors, such as patellar kinematics, probably play a role in the initiation and progression of the disease. The objective of this study was to determine which three-dimensional patellar kinematic parameters (patellar flexion, spin, and tilt and patellar proximal, lateral, and anterior translation) are associated with varus and valgus alignment in subjects with osteoarthritis. METHODS Ten individuals with knee osteoarthritis and varus (five subjects) or valgus (five subjects) knee alignment underwent assessment of three-dimensional patellar kinematics. We used a validated magnetic resonance imaging-based method to measure three-dimensional patellar kinematics in knee flexion while the subjects pushed against a pedal with constant load (80 N). A linear random-effects model was used to test the null hypothesis that there was no difference in the relationship between tibiofemoral flexion and patellar kinematics between the varus and valgus groups. RESULTS Patellar spin was significantly different between groups (p = 0.0096), with the varus group having 2 degrees of constant internal spin and the valgus group having 4.5 degrees of constant external spin. In the varus group, the patellae tracked with a constant medial tilt of 9.6 degrees with flexion, which was significantly different (p = 0.0056) from the increasing medial tilt (at a rate of 1.8 degrees per 10 degrees of increasing knee flexion) in the valgus group. The patellae of the valgus group were 7.5 degrees more extended (p = 0.0093) and positioned 8.8 mm more proximally (p = 0.0155) than the varus group through the range of flexion that was studied. The pattern of anterior translation differed between the groups (p = 0.0011). CONCLUSIONS Our results suggest that authors of future large-scale studies of the relationships between knee mechanics and patellofemoral osteoarthritis should not rely solely on measurements of tibiofemoral alignment and should assess three-dimensional patellar kinematics directly.

Self-management interventions for chronic disease: a systematic scoping review

Objective: To investigate the contributions of physiotherapy and occupational therapy to self-management interventions and the theoretical models used to support these interventions in chronic disease. Data sources: We conducted two literature searches to identify studies that evaluated self-management interventions involving physiotherapists and occupational therapists in MEDLINE, the Cochrane Library, CINAHL, EMBASE, AMED (Allied and Complementary Medicine), SPORTdiscus, and REHABDATA databases. Study selection: Four investigator pairs screened article title and abstract, then full text with inclusion criteria. Selected articles (n = 57) included adults who received a chronic disease self-management intervention, developed or delivered by a physiotherapist and/or an occupational therapist compared with a control group. Data extraction: Four pairs of investigators performed independent reviews of each article and data extraction included: (a) participant characteristics, (b) the self-management intervention, (c) the comparison intervention, (d) outcome measures, construct measured and results. Data synthesis: A total of 47 articles reported the involvement of physiotherapy in self-management compared with 10 occupational therapy articles. The type of chronic condition produced different yields: arthritis n = 21 articles; chronic obstructive pulmonary disease and chronic pain n = 9 articles each. The theoretical frameworks most frequently cited were social cognitive theory and self-efficacy theory. Physical activity was the predominant focus of the self-management interventions. Physiotherapy programmes included disease-specific education, fatigue, posture, and pain management, while occupational therapists concentrated on joint protection, fatigue, and stress management. Conclusions: Physiotherapists and occupational therapists make moderate contributions to self-management interventions. Most of these interventions are disease-specific and are most frequently based on the principles of behaviour change theories.

Longitudinal changes in intermuscular fat volume and quadriceps muscle volume in the thighs of women with knee osteoarthritis

To quantify rates of change in quadriceps muscle (QM) and intermuscular fat (IMF) volumes over 2 years in women in the Osteoarthritis Initiative (OAI) study and examine group differences between those with radiographic osteoarthritis (ROA) and those without ROA.