Knee Osteoarthritis
Conditions
Keywords
Knee osteoarthritis, Shoes, Gait, Biomechanics
Brief summary
The purpose of this study is to determine whether inexpensive, flexible and non-heeled footwear is effective in improving of clinical, functional and gait biomechanics in elderly women with knee osteoarthritis.
Detailed description
* The clinical and functional aspects will be evaluated using a visual analogue scale (VAS) for pain, Western Ontario and McMaster Universities (WOMAC) and Lequesne questionnaires of quality of life in patients with knee osteoarthritis and testing of six-minute walk (6MWT). * Biomechanical analysis of gait will be performed by infrared cameras and a force platform. From the data of kinematics and kinetics, will be calculated moments of the knee joint strength by inverse dynamics. The process (steps) will be divided as follows: * step 1, in this step there will be sorting and initial assessment of potential participants; pain will be evaluated through VAS, function and quality of life by means of questionnaires WOMAC and Lequesne and the 6MWT, and by evaluating the biomechanics of gait. * step 2,(3 month follow-up), both groups will be evaluated again by the VAS and WOMAC and Lequesne questionnaires. * step 3, after 6 months of starting the monitoring process, both groups will be reevaluated through the VAS, WOMAC, Lequesne, 6MWT and biomechanical analysis of gait. This step is the final evaluation, characterizing the end of intervention.
Interventions
OTHERFlexible footwear
The patients of the Intervention Group (IG) will be use over 6 month a flexible and non-heeled footwear (Moleca; Calçados Beira Rio S.A., Novo Hamburgo, Rio Grande do Sul, Brazil) is a women's flexible flat walking shoe, without heels, with an anti-slip rubber sole, 5-mm thin, with a 3 mm internal wedge of ethylene vinyl acetate, made out of dubbed canvas. It had a mean weight of 172 ± 19.6 g, ranging from 142 to 193 g depending upon the size.
Sponsors
University of Sao Paulo General Hospital
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Investigator)
Eligibility
Sex/Gender
FEMALE
Age
60 Years to 80 Years
Healthy volunteers
No
Inclusion criteria
* Kellgren and Lawrence grade 2 or 3 * Being able to walk independently for at least 6 hours per day without the aid of canes or attendant to perform their activities of daily living * Knee pain between 3 and 8 on the visual analogue scale
Exclusion criteria
* Previous history of surgery on knees, ankles and hips in the last 2 years * Neurological disease * BMI \> 35 kg/m2 * Difference in lower limb length \> 1 cm * Prostheses and / or lower limb orthoses * Having received steroid injections and hyaluronic acid intra-articular knee in previous periods of three and six months respectively * Present at the knee joint instability (positive test results in the medial collateral ligament, lateral, anterior and posterior drawer) * OA of the hip and / or ankle incapacitating or diagnosed OA in lower limbs and spine * Inflammatory arthritis (eg. rheumatoid arthritis) * Asymptomatic OA of one or both knees * Dementia or inability to provide consistent information * Introduction of Nonsteroidal Anti-inflammatory Drugs and analgesic medications 8 weeks before inclusion or change of dosage of the same after the inclusion * Being under physiotherapy or acupuncture treatment * Patients with an indication of prosthesis or orthosis * Patients who are already using a flexible and non-heeled shoes for more than 25 hours per week (3 ½ hours per day) over the past 6 months
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Western Ontario and McMaster Universities (WOMAC) Pain Subscale | 6 month | The WOMAC (Western Ontario and McMaster Universities) pain subscale consists of five questions (Likert Scale) relating to the patient's pain in everyday situations. The Likert Scale version used for all WOMAC items are: none, mild, moderate, severe, and extreme. The sum of all items of pain subscale ranges from 0 to 20. Higher scores indicate worse pain. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| WOMAC Physical Function Subscale | 6 month | The physical function subscale included in the WOMAC (Western Ontario and McMaster Universities Osteoarthritis Index) index consists of seventeen questions (Likert Scale) relating to the patient's physical activities, or skills to move out and take care of themselves. The Likert Scale version used for all WOMAC items are: none, mild, moderate, severe, and extreme. The sum of all items of physical function subscale ranges from 0 to 68. Higher scores on the physical function WOMAC subscale indicate worse functional limitations. |
| WOMAC Total Score | 6 month | The WOMAC total score is the sum of all subscale (pain, function and stiffness) (Likert Scale) relating to the patient's physical activities, or skills to move out and take care of themselves. The Likert Scale version used for all WOMAC items are: none, mild, moderate, severe, and extreme. The sum of all items ranges from 0 to 96. Higher scores on the WOMAC total score indicate worse condition. |
| Global Score of the Lequesne´s Questionaire Algo-functional. | 6 month | This questionaire consists of three sections (eleven questions): about pain or discomfort, the maximum distance that the patient can walk, and activities of daily living. Scores range from zero to twenty-four, meaning cases without involvement and with extremely severe impairment, respectively. |
| WOMAC Stiffness Subscale | 6 month | The stiffness subscale included in the WOMAC (Western Ontario and McMaster Universities Osteoarthritis Index) index consists of two questions (Likert Scale) relating articular function of the patient. The Likert Scale version used for all WOMAC items are: none, mild, moderate, severe, and extreme. The sum of all items of the stiffness subscale ranges from 0 to 8. Higher scores on the stiffness WOMAC subscale indicate worse articular function. |
| First Peak of the Knee Adduction Moment (KAM) During Gait. | 6 month | The first peak of the external knee moment was calculated by mean inverse dynamics approach. To this procedure, we used the kinematics data of the lower limbs assessed with six infrared cameras and the ground reaction force evaluated by mean a force platform. This is a continuous measure. |
| Paracetamol Intake | 6 month | Paracetamol intake (500 mg), number of tablets per month. |
| Six-minute Walk Test | 6 month | The six-minute walk test assesses distance in meters walked over 6 minutes. |
Countries
Brazil
Participant flow
Recruitment details
The participants were recruited from the primary care centre of the School of Medicine, University of São Paulo Hospital, and rheumatology ambulatory medical. Participants were recruited between March 2011 and December 2012, and allocated equally into one of two groups.
Participants by arm
| Arm | Count |
|---|---|
| Intervention Group Daily use of the intervention footwear (Moleca®) for 6 months, for at least 42 hours/week (approximately 6 hours/day, 7 days/week). The Moleca® shoe (Calçados Beira Rio S.A., Novo Hamburgo, Rio Grande do Sul, Brazil) is a low-cost women's double canvas, flexible, flat, walking shoe without heels, with a 5-mm anti-slip rubber sole and a 3-mm flat insole of ethylene vinyl acetate that provides only protection but no correction. The mean weight of the shoe is 0.172±0.019 kg (range 0.091 to 0.182 kg), depending on size. This minimalist footwear is commonly worn by the elderly of all social classes and its average cost is US$ 6.25. | 28 |
| Control Group During the intervention period, patients from the Control Group (CG) were instructed not to wear Moleca® or other similar minimalist footwear. During everyday activities, the CG group was only permitted to wear a standard, neutral tennis shoe. At the end of the intervention period, all CG participants also received one pair of Moleca® shoes at no cost. | 28 |
| Total | 56 |
Baseline characteristics
| Characteristic | Control Group | Intervention Group | Total |
|---|---|---|---|
| Age, Categorical <=18 years | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical >=65 years | 9 Participants | 7 Participants | 16 Participants |
| Age, Categorical Between 18 and 65 years | 19 Participants | 21 Participants | 40 Participants |
| Age, Continuous | 66 years STANDARD_DEVIATION 6 | 66 years STANDARD_DEVIATION 5 | 66 years STANDARD_DEVIATION 5 |
| Region of Enrollment Brazil | 28 participants | 28 participants | 56 participants |
| Sex: Female, Male Female | 28 Participants | 28 Participants | 56 Participants |
| Sex: Female, Male Male | 0 Participants | 0 Participants | 0 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | — / — | — / — |
| other Total, other adverse events | 1 / 28 | 0 / 28 |
| serious Total, serious adverse events | 0 / 28 | 0 / 28 |
Outcome results
Primary
Western Ontario and McMaster Universities (WOMAC) Pain Subscale
The WOMAC (Western Ontario and McMaster Universities) pain subscale consists of five questions (Likert Scale) relating to the patient's pain in everyday situations. The Likert Scale version used for all WOMAC items are: none, mild, moderate, severe, and extreme. The sum of all items of pain subscale ranges from 0 to 20. Higher scores indicate worse pain.
Time frame: 6 month
Population: An intention-to-treat analysis was performed, and the missing data were treated as missing completely at random (MCAR) using the Mahalanobis imputation method (SOLAS software version 4.0; Statistical Solutions Ltd., Cork, Ireland).
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Intervention Group | Western Ontario and McMaster Universities (WOMAC) Pain Subscale | WOMAC pain (Baseline) | 9.2 score | Standard Deviation 4 |
| Intervention Group | Western Ontario and McMaster Universities (WOMAC) Pain Subscale | WOMAC pain (3rd month) | 4.5 score | Standard Deviation 2.3 |
| Intervention Group | Western Ontario and McMaster Universities (WOMAC) Pain Subscale | WOMAC pain (6th month) | 3.1 score | Standard Deviation 2.2 |
| Control Group | Western Ontario and McMaster Universities (WOMAC) Pain Subscale | WOMAC pain (Baseline) | 10.0 score | Standard Deviation 3.9 |
| Control Group | Western Ontario and McMaster Universities (WOMAC) Pain Subscale | WOMAC pain (3rd month) | 6.6 score | Standard Deviation 4.7 |
| Control Group | Western Ontario and McMaster Universities (WOMAC) Pain Subscale | WOMAC pain (6th month) | 7.2 score | Standard Deviation 4.8 |
Comparison: Sample size was calculated based on pain WOMAC score and was accomplished using a moderate effect size (f=0.30). Standard deviation estimates were taken from our previous study. A sample size of 56 patients was needed to provide 80% power for detecting a moderate effect difference between the highest and lowest group pain means, with an alpha level of 0.05, a statistical design of F test of repeated measures (between and within effects), and assuming a 10% loss to follow-up.p-value: 0.006Mixed Models Analysis
Comparison: From baseline to 3rd month.p-value: <0.001post hoc newman keuls
Comparison: From baseline to 6th month.p-value: <0.001post hoc Newman Keuls
Comparison: From baseline to 3rd month.p-value: 0.001post hoc Newman-Keuls
Comparison: From baseline to 6th month.p-value: <0.001post hoc Newman-Keuls
Secondary
First Peak of the Knee Adduction Moment (KAM) During Gait.
The first peak of the external knee moment was calculated by mean inverse dynamics approach. To this procedure, we used the kinematics data of the lower limbs assessed with six infrared cameras and the ground reaction force evaluated by mean a force platform. This is a continuous measure.
Time frame: 6 month
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Intervention Group | First Peak of the Knee Adduction Moment (KAM) During Gait. | KAM (Baseline) | 2.44 % body weight x height in centimeters | Standard Deviation 0.77 |
| Intervention Group | First Peak of the Knee Adduction Moment (KAM) During Gait. | KAM (6th month) | 2.37 % body weight x height in centimeters | Standard Deviation 0.63 |
| Control Group | First Peak of the Knee Adduction Moment (KAM) During Gait. | KAM (Baseline) | 2.21 % body weight x height in centimeters | Standard Deviation 1.06 |
| Control Group | First Peak of the Knee Adduction Moment (KAM) During Gait. | KAM (6th month) | 2.28 % body weight x height in centimeters | Standard Deviation 1.12 |
Comparison: We used a casewise two-way ANOVA for repeated measures (two independent groups and three repeated measures/assessments), followed by a post hoc Newman-Keuls test to verify the interaction effect of group vs. time between T0 (baseline), T3 (3th month) and T6 (6th month).p-value: 0.443Mixed Models Analysis
Secondary
Global Score of the Lequesne´s Questionaire Algo-functional.
This questionaire consists of three sections (eleven questions): about pain or discomfort, the maximum distance that the patient can walk, and activities of daily living. Scores range from zero to twenty-four, meaning cases without involvement and with extremely severe impairment, respectively.
Time frame: 6 month
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Intervention Group | Global Score of the Lequesne´s Questionaire Algo-functional. | Lequesne (Baseline) | 9.7 score | Standard Deviation 3.5 |
| Intervention Group | Global Score of the Lequesne´s Questionaire Algo-functional. | Lequesne (3rd month) | 6.3 score | Standard Deviation 3.1 |
| Intervention Group | Global Score of the Lequesne´s Questionaire Algo-functional. | Lequesne (6th month) | 5.5 score | Standard Deviation 3.2 |
| Control Group | Global Score of the Lequesne´s Questionaire Algo-functional. | Lequesne (Baseline) | 11.5 score | Standard Deviation 3.3 |
| Control Group | Global Score of the Lequesne´s Questionaire Algo-functional. | Lequesne (3rd month) | 8.9 score | Standard Deviation 4.3 |
| Control Group | Global Score of the Lequesne´s Questionaire Algo-functional. | Lequesne (6th month) | 9.7 score | Standard Deviation 4.7 |
Comparison: We used a casewise two-way ANOVA for repeated measures (two independent groups and three repeated measures/assessments), followed by a post hoc Newman-Keuls test to verify the interaction effect of group vs. time between T0 (baseline), T3 (3th month) and T6 (6th month).p-value: 0.019Mixed Models Analysis
Comparison: From baseline to 3rd month.p-value: <0.001post hoc Newman-Keuls
Comparison: From baseline to 6th month.p-value: <0.001post hoc Newman-Keuls
Comparison: From baseline to 3rd month.p-value: <0.001post hoc Newman-Keuls
Comparison: From baseline to 6th month.p-value: <0.001post hoc Newman-Keuls
Secondary
Paracetamol Intake
Paracetamol intake (500 mg), number of tablets per month.
Time frame: 6 month
| Arm | Measure | Value (MEDIAN) |
|---|---|---|
| Intervention Group | Paracetamol Intake | 0 tablets per month |
| Control Group | Paracetamol Intake | 10 tablets per month |
Comparison: Difference in paracetamol intake at 6-month.p-value: <0.001Wilcoxon (Mann-Whitney)
Secondary
Six-minute Walk Test
The six-minute walk test assesses distance in meters walked over 6 minutes.
Time frame: 6 month
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Intervention Group | Six-minute Walk Test | Six-minute walk test (Baseline) | 433.5 meter | Standard Deviation 48.9 |
| Intervention Group | Six-minute Walk Test | Six-minute walk test (3rd month) | 453.5 meter | Standard Deviation 40.6 |
| Intervention Group | Six-minute Walk Test | Six-minute walk test (6th month) | 439.3 meter | Standard Deviation 34.7 |
| Control Group | Six-minute Walk Test | Six-minute walk test (Baseline) | 430.6 meter | Standard Deviation 56.8 |
| Control Group | Six-minute Walk Test | Six-minute walk test (3rd month) | 431.6 meter | Standard Deviation 43.1 |
| Control Group | Six-minute Walk Test | Six-minute walk test (6th month) | 428.3 meter | Standard Deviation 44.2 |
Comparison: We used a casewise two-way ANOVA for repeated measures (two independent groups and three repeated measures/assessments), followed by a post hoc Newman-Keuls test to verify the interaction effect of group vs. time between T0 (baseline), T3 (3th month) and T6 (6th month).p-value: 0.425Mixed Models Analysis
Secondary
WOMAC Physical Function Subscale
The physical function subscale included in the WOMAC (Western Ontario and McMaster Universities Osteoarthritis Index) index consists of seventeen questions (Likert Scale) relating to the patient's physical activities, or skills to move out and take care of themselves. The Likert Scale version used for all WOMAC items are: none, mild, moderate, severe, and extreme. The sum of all items of physical function subscale ranges from 0 to 68. Higher scores on the physical function WOMAC subscale indicate worse functional limitations.
Time frame: 6 month
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Intervention Group | WOMAC Physical Function Subscale | WOMAC Physical function subscale (Baseline) | 27.6 score | Standard Deviation 14.3 |
| Intervention Group | WOMAC Physical Function Subscale | WOMAC Physical function subscale (3rd month) | 13.2 score | Standard Deviation 7.3 |
| Intervention Group | WOMAC Physical Function Subscale | WOMAC Physical function subscale (6 month) | 10.2 score | Standard Deviation 6.5 |
| Control Group | WOMAC Physical Function Subscale | WOMAC Physical function subscale (Baseline) | 29.6 score | Standard Deviation 13.2 |
| Control Group | WOMAC Physical Function Subscale | WOMAC Physical function subscale (3rd month) | 20.9 score | Standard Deviation 12.8 |
| Control Group | WOMAC Physical Function Subscale | WOMAC Physical function subscale (6 month) | 23.9 score | Standard Deviation 14.8 |
Comparison: We used a casewise two-way ANOVA for repeated measures (two independent groups and three repeated measures/assessments), followed by a post hoc Newman-Keuls test to verify the interaction effect of group vs. time between T0 (baseline), T3 (3th month) and T6 (6th month).p-value: <0.001Mixed Models Analysis
Comparison: From baseline to 3rd month.p-value: <0.001post hoc Newman-Keuls
Comparison: From baseline to 6th month.p-value: <0.001post hoc Newman-Keuls
Comparison: From baseline to 3rd month.p-value: <0.001post hoc Newman-Keuls
Comparison: From baseline to 6th month.p-value: <0.001post hoc Newman-Keuls
Secondary
WOMAC Stiffness Subscale
The stiffness subscale included in the WOMAC (Western Ontario and McMaster Universities Osteoarthritis Index) index consists of two questions (Likert Scale) relating articular function of the patient. The Likert Scale version used for all WOMAC items are: none, mild, moderate, severe, and extreme. The sum of all items of the stiffness subscale ranges from 0 to 8. Higher scores on the stiffness WOMAC subscale indicate worse articular function.
Time frame: 6 month
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Intervention Group | WOMAC Stiffness Subscale | WOMAC Stiffness subscale (Baseline) | 1.8 score | Standard Deviation 1.9 |
| Intervention Group | WOMAC Stiffness Subscale | WOMAC Stiffness subscale (6th month) | 0.7 score | Standard Deviation 1.1 |
| Intervention Group | WOMAC Stiffness Subscale | WOMAC Stiffness subscale (3rd month) | 0.8 score | Standard Deviation 0.9 |
| Control Group | WOMAC Stiffness Subscale | WOMAC Stiffness subscale (Baseline) | 2.4 score | Standard Deviation 2.3 |
| Control Group | WOMAC Stiffness Subscale | WOMAC Stiffness subscale (3rd month) | 2.9 score | Standard Deviation 2.1 |
| Control Group | WOMAC Stiffness Subscale | WOMAC Stiffness subscale (6th month) | 2.0 score | Standard Deviation 2.4 |
Comparison: We used a casewise two-way ANOVA for repeated measures (two independent groups and three repeated measures/assessments), followed by a post hoc Newman-Keuls to verify the interaction effect of group vs. time between T0 (baseline), T3 (3th month) and T6 (6th month).p-value: 0.015Mixed Models Analysis
Comparison: From baseline to 3rd month.p-value: <0.001post hoc Newman-Keuls
Comparison: From baseline to 6th month.p-value: <0.001post hoc Newman-Keuls
Comparison: From baseline to 3rd month.p-value: <0.001post hoc Newman-Keuls
Comparison: From baseline to 6th month.p-value: <0.001post hoc Newman-Keuls
Secondary
WOMAC Total Score
The WOMAC total score is the sum of all subscale (pain, function and stiffness) (Likert Scale) relating to the patient's physical activities, or skills to move out and take care of themselves. The Likert Scale version used for all WOMAC items are: none, mild, moderate, severe, and extreme. The sum of all items ranges from 0 to 96. Higher scores on the WOMAC total score indicate worse condition.
Time frame: 6 month
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Intervention Group | WOMAC Total Score | WOMAC total score (Baseline) | 37.7 score | Standard Deviation 17.9 |
| Intervention Group | WOMAC Total Score | WOMAC total score (3rd month) | 17.6 score | Standard Deviation 8.9 |
| Intervention Group | WOMAC Total Score | WOMAC total score (6th month) | 14.3 score | Standard Deviation 8.8 |
| Control Group | WOMAC Total Score | WOMAC total score (Baseline) | 42.0 score | Standard Deviation 17.3 |
| Control Group | WOMAC Total Score | WOMAC total score (3rd month) | 30.4 score | Standard Deviation 18.3 |
| Control Group | WOMAC Total Score | WOMAC total score (6th month) | 33.8 score | Standard Deviation 20.3 |
Comparison: We used a casewise two-way ANOVA for repeated measures (two independent groups and three repeated measures/assessments), followed by a post hoc Newman-Keuls test to verify the interaction effect of group vs. time between T0 (baseline), T3 (3th month) and T6 (6th month).p-value: <0.001Mixed Models Analysis
Comparison: From baseline to 3rd month.p-value: <0.001post hoc Newman-Keuls
Comparison: From baseline to 6th month.p-value: 0.019post hoc Newman-Keuls
Comparison: From baseline to 3rd month.p-value: <0.001post hoc Newman-Keuls
Comparison: From baseline to 6th month.p-value: <0.001post hoc Newman-Keuls