The role of orthotics in the management of the diabetic foot Miriam Mulholland

Senior Orthotist- The Royal Wolverhampton NHS Trust MBAPO

Orthotist• Orthotists are autonomous registered practitioners who provide gait analysis and engineering solutions to patients with problems of the neuro, muscular and skeletal systems. They are extensively trained at undergraduate level in mechanics, bio-mechanics, and material science along with anatomy, physiology and pathophysiology. Their qualifications make them competent to design and provide orthoses that modify the structural or functional characteristics of the patients' neuro-muscular and skeletal systems enabling patients to mobilise, eliminate gait deviations, reduce falls, reduce pain, prevent and facilitate healing of ulcers. They are also qualified to modify CE marked Orthoses or componentry taking responsibility for the impact of any changes. They treat patients with a wide range of conditions including Diabetes, Arthritis, Cerebral Palsy, Stroke, Spina Bifida,Scoliosis, MSK, sports injuries and trauma. Whilst they often work as autonomous practitioners they increasingly often form part of multidisciplinary teams such as within the diabetic foot team or neuro-rehabilitation team.

• The diabetic foot is often encapsulated by wound care and ulcer management experts, yet the causes of complex mechanical pathologies are often overlooked in the most severe cases

Orthotic management of the in tact footMechanical Control- To protect the foot and keep it in tact and protect from ulceration- Will depend on the deformities present i.e. hallux rigidus, hammer or claw toes, hallux valgus. - Normally will need insoles/ footwear to reduce pressure if they are high risk

Shoe wear pattern

Orthotic Management of the Intact Diabetic Foot• Stage 1: Normal foot• Patients have low risk of ulceration, normal foot pulses, normal vibration and sensation to the 10g monofilament, no history of ulceration and no significant foot deformity• Annual foot screening• Advice on footwear• Refer for insoles if necessary

Good shoe guide• Toe box should be sufficently long, broad and deep to accommodate the toes without pressing on them, with a clear space between appices of toes and toe box• Shoes should fasten with adjustable lace, strap or velcrohigh on the foot- to hold foot firmly held inside the shoe• The heel should be under 5cm high to reduce pressure on metatarsal heads• Inner lining of shoe should be smooth• Shoes should be purchased in afternoon as feet swell a little in the day• Socks or stockings should be worn to reduce blisters, socks with prominent seams worn inside out

Recommended footwear Female shoe with Velcro and deeper toe box

Male shoe

Available from retailers such asHotter, Easy B, DB shoes, Padders, Pavers, Dr Comfort

Managing Stage 2: High-risk foot• Important to reduce risk of ulcerationMain aim to protect the foot and reduce risk of ulcerationIf the patient doesn’t have deformity will often be in commercially available footwear Running shoes have been shown to reduce pressure on the metatarsals

Hallux Valgus or Hammer toes

Hammer toeShown to increase forefoot pressure and risk of callous build up Hallux valgus stage 3, shown to increase pressure under 2ndMPTJ, and increase risk of plantar hallux ulcerations

Toe spacer to protect hammer toe

Callous under the second metatarsalCan be caused by hallux functional limitus/ rigidusCan be caused by a dropped metatarsal head, or metatarsal fat pad moving forwardCan also be caused by claw/ hammer toes or hallux valgus

• Foot deformities increase foot pressure, therefore these will need offloading with an insole • Hallux valgus increases pressure under 1st/ 2nd

met heads• Also if stage 3 may need footwear to accommodate high toes, and toe box width

Ulceration

Forefoot Offloader

Heel offloader

Footwear• NICE guidelines for diabetic foot state that: Patients with previous history of ulceration, amputation, charcot neuroarthropathy, gross deformity are entitled to two pairs of footwear and TCIs at any timeResearch states that TCIs should be replaced every 6 months to prevent bottoming outMost trusts will only replace footwear when it is ill-fitting or beyond economical repair

Stock/ modular footwear• If there is a normal foot shape- but the patient needs extra depth footwear, stock/modular footwear is used

TCIsTotal contact Insole- Aim to restribute foot pressure and offload areas as needed- Normally custom made- Material depends on patients weight/ activity and where on the foot needs offloading

Charcot Neuroarthropathy

Orthotic Management of Charcot NeuroarthropthyActive stage• Normally present with a red hot swollen foot, may have a history of minor trauma. Temperature difference of at least 2 deghotter than contralateral foot• Orthotic treatment is to offload and prevent deformity, however will depend on where Charcot is

Aircast walkersAdvantagesRemovable to look at dressings/ washingAble to use peg-assisst insoles to offload specific areasAble to use TCIs with them

DisadvantagesPatients may remove them. Research done by Morona et al, 2013 found that removable offloading is less effective at healing plantar forefoot ulcers for this reasonGives the patient a leg length discrepancy

Total Contact Cast• Normally carried out by plaster technician• Shown to be the gold standard in offloading• Lavery et al 2014 showed that a TCC healed a higher proportion of neuropathic plantar foot ulcers than a removable walker with a shear reducing foot bed

Charcot Restraint Orthotic Walker (CROW)• The Charcot Restraint Orthotic Walker, or CROW, is a stable boot designed to accommodate and support a foot with Charcot. CROW showing the hard plastic shell and the Velcro fasteners. The CROW consists of a fully enclosed ankle/foot orthotic with a rocker-bottom sole.

Bespoke footwear

Overlap between Orthotics and Podiatry• Depends on the service• Biomechanics• Gait and posture• Orthotic prescription (depending on podiatry service)

References1. Lavery LA, Higgins KR, La Fontaine J, Zamorano RG, Constantinides GP, Kim PJ. Randomised clinical trial to compare total contact casts, healing sandals and a shear-reducing removable boot to heal diabetic foot ulcers. IntWound J 2014.2. Morona JK, Buckley ES, Jones S,Reddin EA, Merlin TL. Comparison of the clinical effectiveness of different off-loading devices for the treatment of neuropathic foot ulcers in patients with diabetes: a systematic review and meta-analysis. Diabetes Metab Res Rev 2013; 29(3): 183–93.