Article Figures & Data
Figures
- Figure 1
Flow chart of the trial.
ITT = intention-to-treat; PMT = patellar mobilization therapy.
Tables
Characteristic Total
(n = 208)Intervention Group
(n = 104)Control Group
(n = 104)Age, mean (SD), y 60.2 (5.7) 59.4 (5.6) 60.9 (5.8) BMI, No. (%) <18.5 (underweight) 5 (2.4) 1 (1.0) 4 (3.8) 18.5 to <23.0 (normal) 76 (36.5) 37 (35.6) 39 (37.5) 23.0 to <25.0 (overweight) 48 (23.1) 23 (22.1) 25 (24.0) ≥25.0 (obese) 79 (38.0) 43 (41.3) 36 (34.6) Sex, No. (%) Male 41 (19.7) 19 (18.3) 22 (21.2) Female 167 (80.3) 85 (81.7) 82 (78.8) Number of chronic diseases, No. (%) 1 68 (32.7) 35 (33.7) 33 (31.7) 2 64 (30.8) 32 (30.8) 32 (30.8) ≥3 76 (36.5) 37 (35.6) 39 (37.5) Duration of knee pain, mean (SD), y 7.7 (6.6) 6.9 (5.5) 8.5 (7.4) Stanford Expectations of Treatment Scale, mean (SD) Positive expectancy 2.42 (0.90) 2.44 (0.89) 2.39 (0.91) Negative expectancy 5.33 (1.18) 5.41 (1.20) 5.25 (1.16) IPAQ median (IQR), MET score 3,284.8 (2,566.0) 3,353.6 (2,712.5) 3,216.0 (2,445.8) Inactive, No. (%) 14 (6.7) 9 (8.7) 5 (4.8) Minimally active, No. (%) 173 (83.2) 84 (80.8) 89 (85.6) HEPA active, No. (%) 21 (10.1) 11 (10.6) 10 (9.6) Prior treatment for OA knee, No. (%) 128 (61.5) 61 (58.7) 67 (64.4) Knee exercise 25 (12.0) 10 (9.6) 15 (14.4) Physiotherapy 91 (43.8) 45 (43.3) 46 (44.2) Traditional Chinese medicine 79 (38.0) 38 (36.5) 41 (39.4) Other 2 (1.0) 0 (0.0) 1 (1.0) Number of participants on analgesics in the past 7 days, No. (%) 18 (17.3) 11 (10.6) WOMAC, mean (SD) Pain 47.0 (20.7) 46.2 (21.6) 47.7 (19.8) Stiffness 47.0 (25.6) 45.8 (25.6) 48.2 (25.6) Function 45.9 (21.0) 45.8 (21.4) 45.9 (20.6) Total 46.2 (20.4) 45.9 (21.0) 46.5 (19.9) Physical function, mean (SD), s Timed up and go 11.3 (3.7) 11.1 (4.1) 11.4 (3.3) 30-s chair stand 8.8 (3.7) 9.0 (3.9) 8.7 (3.5) 40-m fast-paced walk 39.4 (7.3) 39.6 (22.1) 39.2 (10.4) EuroQoL-5D, mean (SD), score Index 0.58 (0.25) 0.60 (0.26) 0.56 (0.23) VAS 67.3 (15.5) 66.9 (17.1) 67.8 (13.7) BMI = body mass index; HEPA = health-enhancing physical activity; IPAQ = International Physical Activity Questionnaire; IQR = interquartile range; MET = metabolic equivalent; OA = osteoarthritis; SD = standard deviation; VAS = visual analog scale; WOMAC = Western Ontario and McMaster University Osteoarthritis Index.
a Two samples t-test for continuous variable, χ2 test for categorical variable.
Type of Score Total
(n = 326)Intervention Group
(n = 160)Control Group
(n = 166)P Valuea OA knee painb intensity, mean (SD) 63.1 (17.4) 62.6 (17.5) 63.6 (17.4) .636 Kellgren–Lawrence Grade, No. (%) .861 1 (Doubtful JSN, possible osteophytic lipping) 78 (24.3%) 38 (23.9%) 40 (24.7%) 2 (Definite osteophytes, possible JSN on anteroposterior weight-bearing radiograph) 153 (47.7%) 80 (50.3%) 73 (45.1%) 3 (Multiple osteophytes, definite JSN, sclerosis, possible bony deformity) 78 (24.3%) 36 (22.6%) 42 (25.9%) 4 (Large osteophytes, marked JSN, severe sclerosis and definitely bony) 12 (3.7%) 5 (3.1%) 7 (4.3%) Patella position, mean (SD) 0.90 (0.24) 0.91 (0.24) 0.90 (0.24) .751 Degree of pain-free active knee flexion, mean (SD) 124.0 (15.0) 125.8 (12.4) 124.1 (17.1) .380 Analysis Performed Intervention Group (n = 104), mean (SD) Control Group (n = 104), mean (SD) Model 1 Model 2a Between-Group Difference (95% CI) P Value SE Between-Group Difference (95% CI) P Value SE ITT analysis Week 0 46.2 (21.6) 47.7 (19.8) Week 24 28.8 (23.4) 44.3 (22.3) –15.5(–21.9 to – 9.0) <.001 3.3 –15.6(–20.5 to – 10.7) <.001 2.5 Per–protocol analysisb Week 0 47.6 (21.3) 47.6 (19.7) Week 24 29.4 (23.3) 44.3 (22.3) –14.9(–21.4 to – 8.4) <.001 3.3 –16.0(–21.0 to – 11.0) <.001 2.6 Imputed data analysis Week 0 46.2 (21.6) 47.7 (19.8) Week 24 28.9 (24.1) 44.6 (22.8) –15.8(–22.2 to – 9.3) <.001 3.3 –14.9(–20.1 to – 9.8) <.001 2.6 Per–protocol analysis with imputationb Week 0 47.6 (21.3) 47.6 (19.7) Week 24 29.5 (23.3) 44.8 (22.4) –15.3 (–21.9 to – 8.7) <.001 3.3 –15.8 (–20.9 to – 10.7) <.001 2.6 ITT = intention–to–treat; SD = standard deviation; SE = standard error; WOMAC = Western Ontario and McMaster Universities Osteoarthritis Index.
↵a Adjusted for baseline score, duration of knee pain, number of comorbidities, bilateral knee pain status (yes or no), total amount of analgesic consumption, and age.
↵b Included participants who attended all 3 sessions.
- Table 4
Results of Group Effect on WOMAC Stiffness, Function, and Composite Scores, Physical Function Measures, and EuroQoL-5D Using ANCOVA
Type of Score Intervention Group (n = 104), mean (SD) Control Group (n= 104), mean (SD) Imputed Data Analysis Model 1 Imputed Data Analysis Model 2 a Between-Group Difference (95% CI) P Value SE Between-Group Difference (95% CI) P Value SE WOMAC (stiffness) Week 0 45.7 (25.6) 48.2 (25.6) Week 24 27.4 (25.3) 42.9 (26.7) –15.1(–22.7 to – 7.5) <.001 3.8 –13.9(–20.3 to – 7.4) <.001 3.3 WOMAC (function) Week 0 45.8 (20.6) 45.9 (21.4) Week 24 27.7 (23.9) 43.0 (22.5) –15.2(–21.8 to – 8.7) <.001 3.3 –15.1(–20.2 to – 9.9) <.001 2.6 WOMAC (composite) Week 0 45.9 (21.0) 46.5 (19.9) Week 24 27.9 (23.2) 43.3 (21.8) –15.1(–21.8 to – 8.5) <.001 3.4 –14.7(–20.2 to – 9.3) <.001 2.7 30-s chair stand, repetitions Week 0 9.0 (3.9) 8.7 (3.5) Week 24 10.3 (3.8) 8.5 (2.9) 1.8 (0.8 to 2.7) <.001 0.5 1.5 (0.8 to 2.2) <.001 0.3 40-m fast-paced walk, s Week 0 39.6 (22.1) 39.2 (10.4) Week 24 34.6 (9.4) 38.4 (10.7) –3.4(–6.3 to – 0.6) .019 1.5 –3.4 (–6.1 to – 0.8) .012 1.3 Timed up and go, s Week 0 11.1 (4.1) 11.4 (3.3) Week 24 10.0 (3.0) 11.9 (4.3) –1.7(–2.8 to – 0.7) .001 0.5 –1.5(–2.4 to – 0.7) <.001 0.4 EuroQol-5D index Week 0 0.60 (0.26) 0.56 (0.23) Week 24 0.72 (0.25) 0.60 (0.23) 0.11(0.04 to 0.18) .001 0.03 0.11(0.04 to 0.18) .001 0.03 EuroQoL-5D VAS Week 0 66.9 (17.1) 67.8 (13.7) Week 24 72.0 (18.8) 64.8 (15.5) 6.7 (1.6 to 11.8) .010 2.6 7.2 (2.7 to 11.8) .002 2.3 ANCOVA = analysis of covariance; SE = standard error; VAS = visual analog scale; WOMAC = Western Ontario and McMaster Universities Osteoarthritis Index.
↵a Adjusted for baseline score, duration of knee pain, number of comorbidities, bilateral knee pain status (yes or no), total amount of analgesic consumption, and age.
- Table 5
Results of Group Effect on VAS Pain Score & Pain-Free Active Knee Flexion of Individual Treated Knees Using Mixed Linear Regression
Type of Assessment Intervention Group (n = 104), mean (SD) Control Group (n = 104), mean (SD) Imputed Data Analysis Model 1 Imputed Data Analysis Model 2 a Between-Group Difference (95% CI) P Value SE Between-Group Difference (95% CI) P Value SE Pain intensity total (VAS) of treated knee Week 0 62.6 (17.5) 63.6 (17.4) Week 24 42.1 (24.2) 57.7 (23.0) –15.6 (–21.7 to – 9.5) <.001 3.1 –15.0 (–20.5 to – 9.5) <.001 2.8 Degree of pain-free active knee flexion Week 0 125.8 (12.4) 124.1 (17.1) Week 24 130.0 (10.4) 118.6 (19.5) 11.0 (6.7 to 15.3) <.001 2.2 9.3 (6.0 to 12.5) <.001 1.6 SE = standard error; VAS = visual analog scale.
↵a Adjusted for duration of knee pain, number of comorbidities, total amount of analgesic consumption, and age.
Supplemental Appendix
Supplemental Appendix
Files in this Data Supplement:
- Supplemental data: Appendix - PDF file
The Article in Brief
Clinic-Based Patellar Mobilization Therapy for Knee Osteoarthritis: A Randomized Clinical Trial
Regina Wing Shan Sit , and colleagues
Background Knee osteoarthritis is a major cause of pain and disability. Clinical guidelines recommend using non-pharmacological strategies as first-line treatment for knee osteoarthritis, but few clinical trials have evaluated manual therapy and exercise. This study evaluates a simple clinic-based mobilization therapy for the patella (kneecap) applicable in primary care settings.
What This Study Found An intervention combining passive joint mobilization to realign the patellar (kneecap) position, along with exercise to maintain it, can reduce pain and improve function and quality in life in patients with knee osteoarthritis. In a randomized clinical trial, 208 primary care patients with knee osteoarthritis were assigned to either a patella mobilization therapy intervention group or a waiting list (control) group. In the intervention group, physicians mobilized the patellofemoral joint (the joint formed by the kneecap and femur) once every 2 months during three treatment sessions. Patients were placed in a side-lying position with the knee supported and slightly flexed to allow a vertical gravitational glide of the patella from a lateral to medial direction. Physicians also prescribed twice-daily home exercise to encourage continuous firing of the muscle and supervised patients to ensure that they performed the exercises correctly. The waiting list group received patella mobilization therapy after the study period. At 24 weeks, patients in the intervention group demonstrated significantly greater improvement in pain score than those in the waiting list group. Unlike conventional mobilization therapy involving multiple treatment sessions at intense frequency, this technique can easily be performed in primary care practice. The approximate time needed to learn and practice patella mobilization therapy is about one hour. Patient compliance with the study was high, suggesting that it is an acceptable treatment option.
Implications
- Next steps, the authors state, are to compare patella mobilization therapy with other active controls to further confirm its benefits and facilitate its deployment in real-world practice.
