Orthotics: relief for Anterior Knee PainPete Kissel
As many as 1 in 4 active people experience debilitating anterior knee pain. Orthotics are often prescribed for this population, but which patients respond best to this care and what results should those patients expect?
An Australian research group recently determined a clinical prediction rule (basically the key factors) for a positive outcome with orthotics in those with longstanding anterior knee pain: 25 years or older, 165cm or less in height, worst pain described as mild-moderate (<53mm on VAS) and above average midfoot mobility (>11mm measered as midfoot width change from non-weight bearing to weight bearing). Individuals with at least 3 of these factors were found to have a much greater success rate.
In a subsequent study these same factors were used in a randomized controlled trial to determine the efficacy of orthotics over a wait-and-see policy (a common medical approach). 15 of the 20 patients prescribed a orthotic noted that they were either completely recovered, much improved or improved (on the Global improvement scale) over the 6 week trial period. Only 4 out of 20 in the wait and see group reported the same results. Although some of the secondary measures did not seem to be as dramatic, the authors claim that the 6 week trial period may have been too short to detect changes of pain severity.
It appears as though using the above clinical prediction rule, for age, height, pain intensity and midfoot mobility for anterior knee pain can determine potential candidates that will respond well to orthotics. To measure midfoot mobility a standard digital caliper can be used clinically (as seen below). If the difference between non-weight bearing and weight bearing is greater than 11mm then you have more than average midfoot mobility.
As an aside: the same authors previously compared physiotherapy (including patellar mobilisations, patellar taping, and a combination of hip and knee stretches and strengthening exercises), physiotherapy plus orthotics or orthotics alone over a one year period for those with patellofemoral pain syndrome. In this study all groups demonstrated clinically meanful change over the study period, however there was not a significant difference between the groups in outcomes. The practitioners at The Proactive Athlete would still recommend a combined program involving manual care, strengthening and stretching exercises and custom orthotics however a case can be made (for those who satisfy the above clinical prediction rule) for simplifying the management with custom orthotics only.
Contact us to have your midfoot mobility measured and/or determine whether you might be a good candidate for custom orthotics.
Mills K, Blanch P, Dev P, Martin M and Vicenzino B. A randomised control trial of short term efficacy of in-shoe foot orthoses compared with a wait and see policy for anterior knee pain and the role of foot mobility. Br J Sports Med 2011 Published Online First 18 September 2011.?
Vicenzino B, Collins N, Cleland J, et al. A clinical prediction rule for identifying patients with patellofemoral pain who are likely to benefit from foot orthoses: a preliminary determination. Br J Sports Med 2010;44:862–6.
Collins N, Crossley K, Beller E, Darnell R, McPoil T and Vicenzino B. Foot orthoses and phsiotherapy in the treatment of patellofemoral pain syndrome: randomised clinical trial. Br J Sports Med 2009;43:169-171.
McPoil TG, Vicenzino B, Cornwall MW, et al. Reliability and normative values for the foot mobility magnitude: a composite measure of vertical and medial-lateral mobility of the midfoot. J Foot Ankle Res 2009;2:6.