The Immediate Effects Of Foot Orthoses On Functional Performance In Individuals With Patellofemoral Pain Syndrome

Abstract

Symptoms due to patellofemoral pain syndrome (PFPS) often result in recurrent or chronic knee pain and significantly affect functional performance. Although there is some evidence supporting the use of foot orthoses to treat this multifactorial condition, the effects of foot orthoses on functional performance is unclear. PURPOSE: Evaluate the immediate effects of foot orthoses on functional performance, and the association of foot posture and footwear with improved function. METHODS: A cohort of 52 individuals with PFPS (18 - 35 years) was recruited. Each participant was prescribed standard prefabricated foot orthoses (Vasyli Pro, Vasyli International) to wear in their own footwear. Four functional outcome measures were evaluated including the change in pain and ease of a single leg squat on a 5-point Likert scale using Wilcoxin sign rank statistics, and change in the number of pain free step down and single leg rises from sitting using independent t-tests. The association of foot posture using the Foot Posture Index, normalised navicular drop, and calcaneal angle relative to subtalar joint neutral, and the footwear motion control properties scale score with improved function was evaluated using Spearman's rho statistics. RESULTS The majority (between 71 and 83%) of participants demonstrated reduced functional performance for each of the tests evaluated. Prefabricated foot orthoses produced significant improvements (p <.05) for all functional outcome measures. A more pronated foot type was found to be associated with reduced pain and improved ease of completing a single leg squat, and improvements in the number of pain free single leg rises from sitting after foot orthoses prescription (p <.05). Additionally, poorer motion control properties of participant's footwear were found to be associated with reduced pain during the single leg squat and improvements in the number of pain free single leg rises from sitting after foot orthoses prescription (p <.05). CONCLUSION: Prefabricated foot orthoses are able provide immediate improvements to functional performance in individuals with PFPS. Improved functional performance with foot orthoses is associated with a more pronated foot type and poorer footwear motion control properties.