There are some problems associated with diabetic ankle fractures. The biggest problem occurs when what is believed to be a simple ankle fracture is actually a Charcot ankle. The condition of Charcot ankle may not be diagnosed and may lead to a bad outcome such as possible amputation. Diabetic neuropathy often occurs with the loss of protective sensations and is a risk factor for Charcot Ankle. Diabetic ankle fractures have a lot of complications (40% Complication Rate) and the amputation rate is about 6% for closed injuries and approximately 40% for open injuries.
The most significant factor in diabetic patients with ankle fractures is the high risk of infection—up to 20% in diabetic patients—as well as an increased risk of superficial and deep wound infections. Peripheral neuropathy is the most significant risk factor for post-operative complications. If the patient is treated with a splint or a cast, this must be padded very well in order to avoid ulcers or skin complications.
Keep the diabetic patient with an ankle fracture non-weight bearing for a longer period of time—the amount of time spent non-weight bearing is double the time for a diabetic patient. Diabetic patients with an ankle fracture usually have a higher incidence of nonunions, malunions, and hardware failures than with nondiabetic patients. It is important to remember to examine the pulses and check the circulation.
When it comes to treatment, surgery is usually the best option. It is going to take longer for the fracture to heal, so a good stable fixation is needed that will support the fracture until it heals (the fixation will not be traditional).
Important considerations in regards to fixation is:
- Add more fixation and screws with the screws going from the fibula to the tibia.
- Use spanning external fixator
- Use K-wires from the calcaneus to the tibia
I personally like to use minimally invasive techniques. I try not to open the fracture in diabetic patients unless necessary; do it percutaneously with a small incision. I start with getting the fibular length. Next, I fix the medial malleolus percutaneously—the syndesmosis could also be fixed percutaneously.
An important topic related to patients with diabetic ankle fractures and hemoglobin A1c. The orthopaedic surgeon must be aware of the hemoglobin A1c. (I have an entirely separate video on HbA1c, and you can watch that here). We find that HbA1c levels appear to be predictive of risk and complication rates in the surgical treatment and outcome of diabetic patients with ankle fractures. The complication rates are higher among patients with elevated HbA1c, which is more than 6.5%. The normal range of HbA1c is 4-6%. Any reading over 7% is considered high.
Important points:
- •Recognize the Charcot ankle
- •Make sure to examine the circulation and the pulses.
- •Cast or splint must be well padded.
- •There is a high risk of complication that may lead to amputation.
- •Loss of protective sensation and peripheral neuropathy is an important risk factor for charcot ankle.
- •Delay weight bearing because the fracture does not heal quickly.
- •When surgery is done, use percutaneous technique or good fixation that will allow non-failure of the hardware during healing time.
