2 Effect of forefoot rocker sole angle on plantar pressure distribution Trent Salkavich, B App Sc (Pod)Joshua Burns PhD, B App Sc (Pod) HonsLindy Begg, Dip PodCaleb Wegener, B App Sc (Pod) HonsIS IT AVERAGE OVER THE WHOLE GAIT OR IS IT PEAK PLANTAR PRESSURES
3 Definition: Forefoot Rocker Sole Shoe Pressure relieving intervention for the forefoot – prevent ulceration and re-ulceration.Contoured platform that controls joint motion by rocking the foot from heel strike through toe-off in the sagittal planeWalking is achieved by the contour of the rocker bottom forcing the foot to ‘rock’ or ‘tip’ forward when body weight passes over the fulcrum of the shoe.Change to point form
4 The Forefoot Rocker Sole The forefoot rocker sole reduces plantar pressure in the insensate forefoot during gait (Wei-Li et al, 2004) however the relationship between rocker gradient and plantar pressures remains unclear.Examined 4 different offloading conditions on a patient and their affect on ppp
5 Case StudyAimTo assess the effect of different forefoot rockers on peak plantar pressures in a patient with a history of forefoot ulcerationAngle of rocker and its effect on plantar pressures
6 Case Study Medical Hx 56 year old female School teacher Insulin Dependent Diabetes Mellitus – 1985BMI: 27.5HyperlipidemiaPalpable bilateral dorsalis pedis and tibialis posterior pulsesPPG - R130, L 178Sensory neuropathyPresented with osteomyelitic ulcer L 1st MPJ, causal pathway-untreated callousPresent 10 weeks until healedFoot typeCavoid,Foot Posture Index; R -7, L -6Plantarflexed 1st MPJ’s bilaterallyIncreased 1st MPJ stiffness bilaterallyMild hallux abducto valgus bilaterally
7 Methods 15˚, flexible sole, without Thanner™ 4 different conditions were measured :15˚, flexible sole, without Thanner™15˚, flexible sole with Thanner™15˚, rigid sole, with Thanner™17˚, rigid sole, with Thanner™Plantar foot pressures were measured using Novel Pedar System™ whilst the patient walked 2 lengths of a 10 metre flat walkway.Peak plantar pressures were measuredMeasurements were taken consecutively3 different variables, gradient of forefoot rocker, sole flexibility, and with or without Moulded accomodative device (thanner).
16 Pressure Results PRESSURE kPa Flexible, 15˚ Flexible, 15˚ Rigid, 15˚ WHAT IS REGARDED AS A SAFE PRESSURE? Conditions 1-3 resulted in very similar high peak plantar pressures however an increase in only 2 degrees gradient of the forefoot rocker significantly decreased peak plantar pressures. Based on these results the most important variable was not the thanner or the sole rigidity but the gradient of the forefoot rockerFlexible, 15˚Flexible, 15˚Rigid, 15˚Rigid, 17˚CONDITION
17 ResultsA 2˚ increase in forefoot rocker gradient from 15˚ - 17˚ lead to a 26% reduction in forefoot plantar pressure.
18 DiscussionAdditional forefoot rocker angle can assist to significantly reduce peak plantar pressures and should be considered when prescribing footwear.‘Standard’ orthopaedic rocker shoe has a 15˚ forefoot rocker gradient.This case study sets a basis for further research involving rocker gradient and forefoot pressure reduction.
19 Acknowledgements Pierre Marrion – Footwear That Fits Pty Ltd Dr Josh BurnsMs Lindy BeggCaleb Wegner