: PL is a 79 year old man who is 2 days post femoral posterior tibial bypass surgery on a background of a non healing ulcer. Of note his a known vacsulopath with type two insulin dependent diabetes.
HPC:
He presented via the diabetic foot pathway to Vincent’s on 28/12/16 with an ulcer on his left heel. The ulcer had been present with 4 months and developed while hospitalised in October after a right 5th toe amputation. He was treated with IV antibiotics for 6 weeks followed by 2 weeks oral antibiotics. He underwent debridement in the OPD however this failed and the ulcer remained non healing. He complained of calf claudication on 100 metre distance.
Past medical and surgical history:
Type 2 diabetes
HTN
Atrial fibrillation
Angioplasty 2016
Right 5th toe amputation October 2016
Medications:
Novamix IM twice daily
Xarelto
Aspirin 75mg
Antibiotics: Tazocin
Allergies: penicillin (skin rash)
FHX:
Non contributory.
SHX:
Ex-smoker
Non drinker
Lives with wife in a bungalow
Independent in ADL’s
Examination:
Patient was sitting comfortably at 45 degrees. Non healing, 2.5cm ‘punched out’ ulcer present on his left heal. Surrounding skin temperature was cold and pale in colour. No pedal pulses were palpable. Foot sensation was diminished in the ‘stocking’ distribution up to the level of the ankle joint.
Diabetes is a chronic condition which affects glucose metabolism leading to hyperglycaemia which can cause serious microvascular (retinopathy, nephropathy and neuropathy) and macrovascular (stroke, limb ischaemia and heart disease) complications1. People with diabetes are prone to foot pathologies including diabetic neuropathy, occlusive peripheral arterial disease (PAD), charcot neuropathy, osteomyelitis all of which can lead to foot ulceration2. Diabetic ulcers can be arterial, neuropathic or a mix of the two, with neuropathy being the most common (>60% of diabetic foot ulcers). 3
Neuropathy affects sensory, motor and autonomic components and causes foot deformities and anhydrosis, increasing susceptibility to bacterial infections and loss of the protective response which all cumulatively lead to ulcer development. Chronic hyperglycaemia correlates with loss of nerve function ultimately causing neuropathy. 2
Ischaemia due to PAD is also an underlying cause of diabetic foot ulcers1. Atherosclerosis is more common in people with diabetes and tends to affect the tibial and perineal arteries of the calf. Chronic hyperglycemia results in endothelial cell dysfunction and smooth cell abnormalities in the peripheral arteries which cause vasoconstriction leading to an occlusive arterial disease that causes ischaemia in the lower extremity resulting in an increased ulceration risk.1
The surgical procedure chosen was a femoral-posterior tibial bypass surgery using the long saphenous vein. This surgery was chosen as the occlusion was long and angioplasty failed.
Good glycemic control is of the utmost importance to improve healing of the ulcers and regular foot care is essential3. Other conservative measures include offloading of the affected foot by crutches, total contact casts or plastic walkers. Offloading aids healing by preventing continuous trauma to the foot4. Infected ulcers require antibiotic treatment with benzylpenicillin, flucloxacillin and metrondiazole.4 The patient underwent debridement which failed to reach clean bone and a failed angioplasty on the 13/01/2017. All of the above measures were exhausted so surgery was indicated. The final treatment option is amputation.
Complications of this procedure are separated into early and late and complications specific to femoral posterior tibial bypass surgery. Early complications include wound infection, graft infection, post operative bleeding and occlusion5. Late complications include graft sepsis and false aneurysm, while specific complications include graft leakage and nerve injury.5
This case highlighted the importance of the diabetic foot pathway where it divides patients into low, moderate and high risk patients and those with active foot disease 6. These patients are monitored in accordance to their risk assessment and treated accordingly. This shows that prevention is the best treatment of ulcers and good glycemic control and foot care can prevent their occurrence.6