Background
Methods
Participants
Questionnaires and clinical assessments
Interventions
Definition of responders and non-responders
Statistical analysis
Results
Participants
Differences between responders and non-responders in the orthoses group
Non-responders (n = 18) | Responders (n = 29) | |
---|---|---|
Demographics/anthropometrics | ||
Age, years–mean (SD) | 59.0 (11.3) | 57.1 (10.0) |
Females–n (%) | 8 (44) | 18 (62) |
Body mass index, kg/m2–mean (SD) | 27.9 (5.1) | 29.6 (4.72) |
General health/physical activity | ||
SF 12 physical component score–mean (SD) a
| 43.2 (12.1) | 45.2 (10.2) |
SF 12 mental component score–mean (SD) a
| 57.1 (9.5) | 54.4 (6.5) |
Physical activity, total hours per week–mean (SD) | 20.9 (10.5) | 17.1 (17.2) |
Pain characteristics | ||
Pain duration, months–median (IQR) | 33 (101) | 30 (59) |
Pain severity at rest–mean (SD) b
| 3.1 (3.0) | 3.4 (2.3) |
Pain severity while walking–mean (SD) b
| 3.8 (2.3) | 5.2 (2.1)*
|
Stiffness in the morning–mean (SD) b
| 2.4 (2.4) | 3.6 (2.8) |
Stiffness later in the day–mean (SD) b
| 2.3 (2.7) | 3.9 (2.7) |
FHSQ pain–mean (SD) a
| 61.5 (23.4) | 53.5 (17.6) |
FHSQ function–mean (SD) a
| 77.1 (18.6) | 66.2 (24.8) |
FFI pain–mean (SD) a
| 34.8 (15.6) | 44.8 (17.9) |
FFI difficulty–mean (SD) a
| 26.9 (20.2) | 43.9 (26.3)*
|
FFI stiffness–mean (SD) a
| 28.1 (18.7) | 36.7 (20.8) |
Pain Catastrophising Scale–mean (SD) b
| 8.2 (7.8) | 10.0 (8.9) |
Foot posture and range of motion | ||
Foot posture index–mean (SD) | 2.9 (2.7) | 2.9 (2.4) |
1st MTPJ range of motion (°)–mean (SD) | 41.2 (12.6) | 40.3 (11.7) |
Radiographic severity | ||
None–n (%) | 0 (0) | 0 (0) |
Mild–n (%) | 3 (17) | 12 (41) |
Moderate–n (%) | 7 (39) | 6 (21) |
Severe–n (%) | 8 (44) | 11 (38) |
Biomechanical effects of intervention | ||
1st MTPJ peak pressure: own shoes, kPa–median (IQR) | 188.8 (100.0) | 150.0 (60.0) |
1st MTPJ peak pressure: intervention, kPa–median (IQR) | 161.3 (68.8) | 125.0 (70.0) |
% reduction in 1st MTPJ peak pressure–median (IQR) | 14.0 (24.7) | 13.6 (16.3) |
Credibility and Expectancy Questionnaire | ||
Credibility–mean (SD) | 19.6 (2.4) | 21.2 (3.2) |
Expectancy–mean (SD) | 17.3 (3.4) | 16.9 (4.1) |
Total hours intervention worn during study–mean (SD) | 332 (202) | 518 (245)*
|
Differences between responders and non-responders in the rocker-sole footwear group
Non-responders (n = 25) | Responders (n = 16) | |
---|---|---|
Demographics/anthropometrics | ||
Age, years–mean (SD) | 56.9 (8.4) | 55.9 (12.4) |
Females–n (%) | 14 (56) | 11 (69) |
Body mass index, kg/m2–mean (SD) | 28.4 (4.1) | 28.3 (4.9) |
General health/physical activity | ||
SF 12 physical component score–mean (SD) a
| 45.8 (10.2) | 45.4 (9.8) |
SF 12 mental component score–mean (SD) a
| 52.2 (8.1) | 51.7 (10.8) |
Physical activity, total hours per week–mean (SD) | 14.5 (11.0) | 16.8 (10.1) |
Pain characteristics | ||
Pain duration, months–median (IQR) | 36 (108) | 24 (75) |
Pain severity at rest–mean (SD) b
| 3.4 (2.7) | 3.5 (2.3) |
Pain severity while walking–mean (SD) b
| 4.7 (2.2) | 5.1 (2.1) |
Stiffness in the morning–mean (SD) b
| 3.9 (2.9) | 4.1 (1.6) |
Stiffness later in the day–mean (SD) b
| 3.7 (2.8) | 3.7 (2.2) |
FHSQ pain–mean (SD) a
| 52.6 (19.7) | 45.9 (17.9) |
FHSQ function–mean (SD) a
| 70.8 (23.4) | 62.5 (28.0) |
FFI pain–mean (SD) a
| 41.1 (16.6) | 47.1 (18.3) |
FFI difficulty–mean (SD) a
| 37.2 (25.3) | 45.9 (23.3) |
FFI stiffness–mean (SD) a
| 31.8 (22.9) | 44.4 (16.7)*
|
Pain Catastrophising Scale–mean (SD) b
| 9.2 (6.9) | 10.6 (7.9) |
Foot posture and range of motion | ||
Foot posture index–mean (SD) | 3.5 (2.0) | 3.6 (2.2) |
1st MTPJ range of motion (°)–mean (SD) | 41.4 (13.4) | 38.5 (13.8) |
Radiographic severity | ||
None–n (%) | 1 (4) | 3 (20) |
Mild–n (%) | 3 (13) | 2 (13) |
Moderate–n (%) | 16 (70) | 2 (13) |
Severe–n (%) | 3 (13) | 8 (53)*
|
Biomechanical effects of intervention | ||
1st MTPJ peak pressure: own shoes, kPa–mean (SD) | 167.5 (62.5) | 158.3 (40.6) |
1st MTPJ peak pressure: intervention, kPa–mean (SD) | 133.2 (49.1) | 137.3 (36.8) |
% reduction in 1st MTPJ peak pressure | 19.5 (18.0) | 11.2 (19.8) |
Credibility and Expectancy Questionnaire | ||
Credibility–mean (SD) | 21.0 (3.6) | 21.3 (3.3) |
Expectancy–mean (SD) | 17.1 (5.3) | 19.1 (4.4) |
Footwear perceptions (100 mm visual analog scales) | ||
Shoe attractiveness (to self)–mean (SD) | 40.1 (20.4) | 50.7 (26.3) |
Shoe attractiveness (to others)–mean (SD) | 38.4 (20.7) | 48.7 (21.8) |
Shoe comfort–mean (SD) | 61.6 (26.6) | 64.3 (18.5) |
Ease of donning and doffing shoes–mean (SD) | 76.6 (21.1) | 79.6 (16.5) |
Perception of shoe fit–median (IQR) | 82.0 (21.0) | 77.5 (16.0) |
Perception of shoe heaviness–mean (SD) | 46.1 (25.2) | 44.7 (18.7) |
Total hours intervention worn during study–mean (SD) | 278 (200) | 320 (179) |
Discriminant function analysis
Orthoses group (n = 47) | Rocker-sole footwear group (n = 41) | |
---|---|---|
Wilk’s lambda, chi-square, p
| λ = 0.77, χ
2 = 10.9, p = 0.012 | λ = 0.91, χ
2 = 3.5, p = 0.175 |
Predictor variable (discriminant function coefficient) | Total hours intervention worn during study (0.681) | Foot Function Index stiffness (1.00) |
Pain severity while walking (0.468) | Radiographic severity (0.287) | |
Foot Function Index difficulty (0.361) | ||
% of cases correctly classified | 73.3 | 63.2 |
% of cases correctly classified following validation | 62.2 | 52.6 |