Current Concepts In Surgical Offloading Of The Diabetic Foot
When conservative offloading options have failed and patients with diabetes are at risk of limb loss, one might consider surgical offloading for diabetic foot ulcers. These authors offer their experience with operative techniques for offloading ulcers in areas such as the midfoot, first ray and lesser metatarsals.
Treating deformity and secondary ulceration in the diabetic foot is a complicated endeavor. Multiple comorbidities such as polyneuropathy, peripheral arterial disease, large body mass indices and marginal adherence have the potential to sabotage the most thoughtful surgical plan.
Accordingly, it is necessary to scrutinize each patient with a diabetic foot ulceration and the patient’s underlying etiologies prior to executing any surgical plan. Often, we overlook underlying deformity and pathomechanics when treating diabetic ulceration. In this article, we will discuss several surgical offloading measures that one can employ to treat or prevent ulceration.
Historically, offloading of ulcers and pre-ulcerative areas has been a mainstay in the treatment of the diabetic foot. Non-surgical offloading modalities such as total contact casts, Charcot restraint orthotic walker (CROW) boots and orthoses are among the options.
The question remains: when does one consider surgical intervention for the diabetic foot? We must temper the indications for surgical intervention against the potential risk of infection, Charcot neuroarthropathy and loss of limb. In general, we feel depth shoes and custom insoles can be effective in managing a plantigrade foot without osseous prominence or tendon contracture such as equinus.
One needs to approach operative management of the diabetic foot in a rational and systematic fashion. A dogmatic surgical approach will often lead to failure and possible limb loss. It is imperative that the surgeon does a thorough examination and determines the procedure that would best eliminate or prevent re-ulceration in the patient with diabetes. Often, there is a logical underlying biomechanical abnormality or osseous deformity that surgeons must address in order to properly correct the problem.
Podiatric surgeons should follow basic principles when trying to offload the diabetic foot surgically. First, only perform surgery if conservative care has failed or the foot/ankle is at risk for imminent infection or amputation. Second, one must understand the biomechanics that are placing the foot at risk. Lastly, when addressing the deformity, there is a need in some instances to address proximal pathology to correct distal pedal issues.
Pertinent Pearls On Correcting Hindfoot Malalignment
A common example of a difficult to treat ulceration is a sub-fifth metatarsal head ulceration secondary to a fixed hindfoot varus. These plantar lesions are difficult to manage with orthotics and shoe modifications. The fixed varus makes the foot more rigid and less able to adapt to sagittal pressure.
In addition, equinus exacerbates these ulcerations. We feel that by correcting the hindfoot alignment with a lateral closing wedge osteotomy and gastrocnemius recession, outcomes are predictably successful.