2. Effect of forefoot rocker sole angle on plantar pressure distribution
Trent Salkavich, B App Sc (Pod)
Joshua Burns PhD, B App Sc (Pod) Hons
Lindy Begg, Dip Pod
Caleb Wegener, B App Sc (Pod) Hons
IS 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 plane
Walking 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 Study
Aim
To assess the effect of different forefoot rockers on peak plantar pressures in a patient with a history of forefoot ulceration
Angle of rocker and its effect on plantar pressures

6. Case Study Medical Hx 56 year old female School teacher
Insulin Dependent Diabetes Mellitus – 1985
BMI: 27.5
Hyperlipidemia
Palpable bilateral dorsalis pedis and tibialis posterior pulses
PPG - R130, L 178
Sensory neuropathy
Presented with osteomyelitic ulcer L 1st MPJ, causal pathway-
untreated callous
Present 10 weeks until healed
Foot type
Cavoid,
Foot Posture Index; R -7, L -6
Plantarflexed 1st MPJ’s bilaterally
Increased 1st MPJ stiffness bilaterally
Mild 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 measured
Measurements were taken consecutively
3 different variables, gradient of forefoot rocker, sole flexibility, and with or without Moulded accomodative device (thanner).

8. Test 1: 15˚, flexible sole, without Thanner™
Conditions
Original prescribed footwear 7 weeks old
Standard 15˚ rocker
flexible sole
No moulded accomodative orthoses (Thanner™)

9. Test 1: 150, flexible sole, without Thanner™

10. Test 2, 15˚, flexible, Thanner™
Conditions
Standard shoe
15˚ rocker
Flexible sole
Thanner™
Shoe condition then new slide with results

11. Test 2 -15˚ , Flexible , Thanner™

12. Test 3 15˚, rigid, Thanner™
Conditions
Rigid sole
15˚ rocker
Thanner™

13. Test ˚, rigid, Thanner™

14. Test 4 - 17˚, rigid, Thanner™ Conditions 17˚ rocker Rigid sole

15. Test ˚, rigid, 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 rocker
Flexible, 15˚
Flexible, 15˚
Rigid, 15˚
Rigid, 17˚
CONDITION

17. Results
A 2˚ increase in forefoot rocker gradient from 15˚ - 17˚ lead to a 26% reduction in forefoot plantar pressure.

18. Discussion
Additional 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 Burns
Ms Lindy Begg
Caleb Wegner