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Does foot mobility mediate the effects of foot orthoses on knee load during walking in people with patellofemoral pain?
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Abstracts / Journal of Science and Medicine in Sport 20S (2017) e67–e105
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People with patellofemoral osteoarthritis have greater foot pronation and mobility, and lower ankle dorsiflexion, compared to controls
Does foot mobility mediate the effects of foot orthoses on knee load during walking in people with patellofemoral pain?
N. Wyndow 1,∗ , N. Collins 1 , K. Tucker 2 , B. Vicenzino 1 , K. Crossley 3
N. Collins 1,∗ , H. Hart 2 , J. Bonacci 3 , B. Vicenzino 1 , K. Crossley 2
1 School of Health and Rehabilitation Sciences, The University of Queensland, Australia 2 School of Biomedical Sciences, The University of Queensland, Australia 3 Latrobe University, Australia
1 School of Health and Rehabilitation Sciences, The University of Queensland, Australia 2 La Trobe Sport and Exercise Medicine Research Centre, La Trobe University, Australia 3 School of Exercise and Nutrition Sciences, Deakin University, Australia
Background: The patellofemoral (PF) joint is the knee compartment most commonly affected by osteoarthritis (OA). Even mild PFOA is associated with pain and functional limitations. Despite its impact, little is understood of the aetiological, structural and functional features of PFOA. Based on similarities in symptoms and biomechanics, known features of PF pain in younger adults (aged <40 years) may also occur in people with PFOA. In people with PF pain, increased midfoot mobility, reduced ankle joint dorsiflexion (AJTDFL) and increased frontal plane projection angle (FPPA), which is a measure of knee valgus during a single leg squat (SLSq), have been observed. This study aimed to: (i) determine whether people with PFOA demonstrate differences in foot and ankle characteristics compared to controls; and (ii) investigate the relationship between foot and ankle characteristics and FPPA. Methods: 27 individuals with PFOA (18 (67%) women, mean (SD): 60 (9) years; 168 (8) cm; 73 (14) kg) and 23 controls (13 (56%) women, 56 (8) years, 172 (10) cm, 72 (16) kg) participated. Foot mobility was quantified as the difference in dorsal midfoot arch height, and in midfoot width, between non-weight bearing and bilateral weight bearing (50% total body weight), at 50% of the total foot length. Static foot posture was rated using the Foot Posture Index (FPI). AJTDFL range of motion was measured using the knee to wall test. FPPA was measured at the deepest part of a SLSq to 45◦ , as the angle at the knee formed by lines connecting the anterior superior iliac spine, the midpoint of the femoral condyles, and the midpoint of the malleoli. Generalized estimating equations were utilized. Results: The PFOA group had lower AJTDFL (p = 0.001; B = 1.88), greater arch height mobility (p = 0.002; B = 1.79), greater midfoot width mobility (p = 0.005; B = 1.71), and greater FPI (p = 0.03; B = 1.20) compared to healthy controls. In PFOA, lower AJTDFL and greater arch height mobility were significantly associated with higher FPPA (more knee valgus) (p < 0.05), while lower AJTDFL was associated with greater FPPA in controls (p = 0.03). Discussion: People with PFOA have higher arch and midfoot mobility, a more pronated foot type, and lower AJTDFL compared to healthy controls. Foot and ankle features exerted differing effects on the FPPA during SLSq in PFOA compared to controls. Interventions addressing foot mobility and ankle range should be considered in people with PFOA. http://dx.doi.org/10.1016/j.jsams.2017.01.084
Background: Sports medicine practitioners often use prefabricated (‘off-the-shelf’) foot orthoses when managing patients with patellofemoral pain (PFP). While clinical trials demonstrate their efficacy, individual response to foot orthoses intervention can vary substantially. Our previous work suggests that a subgroup of people with PFP, who have greater foot mobility, have a greater likelihood of success with prefabricated foot orthoses. This subgroup may be more responsive to a mechanical foot intervention, and demonstrate more consistent changes in knee load in response to foot orthoses. The aim of this study was to determine whether people with PFP and mobile feet exhibit different immediate effects on knee load when walking with foot orthoses, compared to shoes alone, than those with PFP and less mobile feet. Methods: A within-subject, repeated measures study recruited 36 people with chronic PFP (duration 3 months, 19 females; mean ± SD 36 ± 7 years; BMI 25 ± 4 kg/m2 ). Midfoot width mobility was calculated as the difference in midfoot width (measured at 50% foot length) between weight bearing and non-weight bearing positions, with greater values indicating greater mobility. K-means cluster analysis was used to classify participants into two homogenous groups based on midfoot width mobility (Group 1: 2.3–9.3 mm; Group 2: 9.8–17.4 mm). A nine-camera VICON motion analysis system (Oxford Metrics) and three AMTI groundembedded force plates were used to capture 3D motion analysis during level walking, under two conditions: (i) sandal (Nike Strap Runner); and (ii) sandal with prefabricated foot orthoses (Vasyli International). Peak external knee adduction moment (KAM; first peak) was calculated for each condition, and the average of three trials used. Differences in peak KAM between shoe and orthoses conditions were calculated separately for each foot mobility group using paired t tests (p < 0.05). Results: Group 2 demonstrated a significant increase in peak KAM when walking with foot orthoses, compared to shoes (mean difference 0.03 Nm/kg, 95% CI 0.01–0.05, p = 0.015). No significant difference was observed in Group 1 (0.002 Nm/kg, −0.02 to 0.02, p = 0.855). Discussion: In people with PFP, prefabricated foot orthoses appear to change frontal plane knee load during walking in those with greater midfoot mobility, but not in those with less mobility. Notably, the direction of change is favourable in a population that typically demonstrates increased dynamic knee valgus (abduction). Findings suggest that biomechanical factors may play a role in therapeutic outcomes of foot orthoses for PFP, but only in those with more mobile feet. http://dx.doi.org/10.1016/j.jsams.2017.01.085
Abstracts / Journal of Science and Medicine in Sport 20S (2017) e67–e105
236
237
People with patellofemoral osteoarthritis have greater foot pronation and mobility, and lower ankle dorsiflexion, compared to controls
Does foot mobility mediate the effects of foot orthoses on knee load during walking in people with patellofemoral pain?
N. Wyndow 1,∗ , N. Collins 1 , K. Tucker 2 , B. Vicenzino 1 , K. Crossley 3
N. Collins 1,∗ , H. Hart 2 , J. Bonacci 3 , B. Vicenzino 1 , K. Crossley 2
1 School of Health and Rehabilitation Sciences, The University of Queensland, Australia 2 School of Biomedical Sciences, The University of Queensland, Australia 3 Latrobe University, Australia
1 School of Health and Rehabilitation Sciences, The University of Queensland, Australia 2 La Trobe Sport and Exercise Medicine Research Centre, La Trobe University, Australia 3 School of Exercise and Nutrition Sciences, Deakin University, Australia
Background: The patellofemoral (PF) joint is the knee compartment most commonly affected by osteoarthritis (OA). Even mild PFOA is associated with pain and functional limitations. Despite its impact, little is understood of the aetiological, structural and functional features of PFOA. Based on similarities in symptoms and biomechanics, known features of PF pain in younger adults (aged <40 years) may also occur in people with PFOA. In people with PF pain, increased midfoot mobility, reduced ankle joint dorsiflexion (AJTDFL) and increased frontal plane projection angle (FPPA), which is a measure of knee valgus during a single leg squat (SLSq), have been observed. This study aimed to: (i) determine whether people with PFOA demonstrate differences in foot and ankle characteristics compared to controls; and (ii) investigate the relationship between foot and ankle characteristics and FPPA. Methods: 27 individuals with PFOA (18 (67%) women, mean (SD): 60 (9) years; 168 (8) cm; 73 (14) kg) and 23 controls (13 (56%) women, 56 (8) years, 172 (10) cm, 72 (16) kg) participated. Foot mobility was quantified as the difference in dorsal midfoot arch height, and in midfoot width, between non-weight bearing and bilateral weight bearing (50% total body weight), at 50% of the total foot length. Static foot posture was rated using the Foot Posture Index (FPI). AJTDFL range of motion was measured using the knee to wall test. FPPA was measured at the deepest part of a SLSq to 45◦ , as the angle at the knee formed by lines connecting the anterior superior iliac spine, the midpoint of the femoral condyles, and the midpoint of the malleoli. Generalized estimating equations were utilized. Results: The PFOA group had lower AJTDFL (p = 0.001; B = 1.88), greater arch height mobility (p = 0.002; B = 1.79), greater midfoot width mobility (p = 0.005; B = 1.71), and greater FPI (p = 0.03; B = 1.20) compared to healthy controls. In PFOA, lower AJTDFL and greater arch height mobility were significantly associated with higher FPPA (more knee valgus) (p < 0.05), while lower AJTDFL was associated with greater FPPA in controls (p = 0.03). Discussion: People with PFOA have higher arch and midfoot mobility, a more pronated foot type, and lower AJTDFL compared to healthy controls. Foot and ankle features exerted differing effects on the FPPA during SLSq in PFOA compared to controls. Interventions addressing foot mobility and ankle range should be considered in people with PFOA. http://dx.doi.org/10.1016/j.jsams.2017.01.084
Background: Sports medicine practitioners often use prefabricated (‘off-the-shelf’) foot orthoses when managing patients with patellofemoral pain (PFP). While clinical trials demonstrate their efficacy, individual response to foot orthoses intervention can vary substantially. Our previous work suggests that a subgroup of people with PFP, who have greater foot mobility, have a greater likelihood of success with prefabricated foot orthoses. This subgroup may be more responsive to a mechanical foot intervention, and demonstrate more consistent changes in knee load in response to foot orthoses. The aim of this study was to determine whether people with PFP and mobile feet exhibit different immediate effects on knee load when walking with foot orthoses, compared to shoes alone, than those with PFP and less mobile feet. Methods: A within-subject, repeated measures study recruited 36 people with chronic PFP (duration 3 months, 19 females; mean ± SD 36 ± 7 years; BMI 25 ± 4 kg/m2 ). Midfoot width mobility was calculated as the difference in midfoot width (measured at 50% foot length) between weight bearing and non-weight bearing positions, with greater values indicating greater mobility. K-means cluster analysis was used to classify participants into two homogenous groups based on midfoot width mobility (Group 1: 2.3–9.3 mm; Group 2: 9.8–17.4 mm). A nine-camera VICON motion analysis system (Oxford Metrics) and three AMTI groundembedded force plates were used to capture 3D motion analysis during level walking, under two conditions: (i) sandal (Nike Strap Runner); and (ii) sandal with prefabricated foot orthoses (Vasyli International). Peak external knee adduction moment (KAM; first peak) was calculated for each condition, and the average of three trials used. Differences in peak KAM between shoe and orthoses conditions were calculated separately for each foot mobility group using paired t tests (p < 0.05). Results: Group 2 demonstrated a significant increase in peak KAM when walking with foot orthoses, compared to shoes (mean difference 0.03 Nm/kg, 95% CI 0.01–0.05, p = 0.015). No significant difference was observed in Group 1 (0.002 Nm/kg, −0.02 to 0.02, p = 0.855). Discussion: In people with PFP, prefabricated foot orthoses appear to change frontal plane knee load during walking in those with greater midfoot mobility, but not in those with less mobility. Notably, the direction of change is favourable in a population that typically demonstrates increased dynamic knee valgus (abduction). Findings suggest that biomechanical factors may play a role in therapeutic outcomes of foot orthoses for PFP, but only in those with more mobile feet. http://dx.doi.org/10.1016/j.jsams.2017.01.085