Rockwood Adults CH64

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CHAPTER 64 • Ankle Fractures

are no studies considering outcomes following weightbearing without immobilization, presumably because this would rep- resent a practical difficulty for most patients. Studies reporting good outcomes with patients managed with early weightbear- ing have often excluded certain patient groups, particularly patients unable to comply fully with guidance 3,4,6,396 and those with potentially unstable fixation 111,396 and as a result extrapo- lation of this evidence to all patients with ankle fractures may not be justified. Patients with dementia, neuropathy, IV drug abuse and excessive alcohol consumption may not be suitable for early weightbearing. There is some evidence suggesting that following fixation of the syndesmosis patients are best managed with a period of non–weight-bearing mobilization (see above). Early active movement of the ankle appears to be safe although once again no significant long-term benefits have been shown over a period of immobilization. 4,92,101,111,147,350 Follow- ing immobilization no convincing benefits of manual therapy, 218 passive stretching or a specific training plan 276 as part of a pro- gram of physiotherapy has been demonstrated. Driving Patients should be warned of the risks of driving after ankle frac- ture, particularly after right-sided injury. Waton et al. investigated patients immobilized following ankle fracture in a driving simu- lator. They found that while immobilized in a cast or functional brace there is a significant increase in total brake reaction time. 283 Even healthy volunteers immobilized in a cast or functional brace have been shown to have increased braking distances. 391,406 Patients should therefore be strongly encouraged not to drive during their period of immobilization. Despite this, a small minority of patients admit to driving while immobilized in a below-knee cast. 184 After release from immobilization, patients still have an increased total braking and travel time compared to normal con- trols, but by 9 weeks postoperatively this impairment appears to have resolved. 103 Therefore it appears that at 3 weeks after removal of their cast, patients can safely resume driving. Under United Kingdom law this is a matter for the patient and patients should be encouraged to assess their own “fitness to drive.” 401 Authors preferred treatment: Although return to driving is largely a matter between the patient and law enforcement, we advise patients that a pragmatic guide to the return of adequate neuromuscular control to brake safely is the ability to descend stairs in a reciprocal manner with one foot on each step. Complicated Patient Groups There are a number of patient groups who need to be consid- ered separately because of the potential complications inherent in the treatment of ankle fractures. They are listed in Table 64-3, which also lists the particular complications that may occur in these groups. Diabetics A number of the long-term complications of diabetes may impact upon ankle fracture management including impaired wound and fracture healing and peripheral neuropathy. Because of the incidence of diabetes within most developed populations,

TABLE 64-3. Risk Factors After Ankle Fracture

Diabetes

• Requires perioperative management with close glucose monitoring • Wound dehiscence/infection in up to 32% 113 • Charcot neuroarthropathy—increases risk of construct failure during fracture healing: Consider an extended period (8–10 weeks) of protected weight bearing 72

Increases risk of fixation failure by up to three times 42

Obesity

Smoking Increases risk of deep infection by six times 272

Stopping smoking after ankle fracture reduces this risk 270

Alcohol

Wound dehiscence/infection four times higher in alcohol abusers 382

a significant body of work has been undertaken on the impact of diabetes on ankle fracture management and outcomes. Some surgeons have reported extremely high rates of com- plications in diabetics who sustain ankle fractures. McCormack and Leith 241 reported a 42% complication rate in their diabetic patients in comparison to no complications in their controls; they also reported a 10.5% rate of death among the operatively treated diabetics. Blotter et al. 39 reported an overall complication rate of 43% among operatively treated diabetic patients in comparison to 15% in controls and Flynn et al. 113 reported a significantly higher infection rate in diabetic patients (32%) than controls (8%) with even higher rates in the cohort of patients that were noncompliant with diabetic management. Extremely high levels of infection have been seen in open ankle fractures with White et al. 412 reporting a 64% rate of wound infection and a 42% rate of amputation. This can have a significant impact on the costs associated with the care of diabetic patients with ankle fractures with Ganesh et al. 120 estimating a $2,000 excess per patient. As would be expected, patient-reported outcomes are significantly poorer in diabetics. 104 Well-controlled, uncomplicated diabetics may have a better outcome: Larger studies have found no significant difference in infection rates when all diabetics are considered together, whereas subgroup analysis of patients with the complications of diabetes has revealed a significantly higher rate of complications after ankle fracture. 173,420 The major risk factor seems to be neu- roarthropathy, which is perhaps not surprising given the impor- tance of neuromuscular control of ankle stability. 248 Costigan et al. 72 reported a rate of complications of 14% in their cohort of operatively treated diabetic patients, again finding significantly higher rates in patients with associated peripheral neuropathy and vascular disease; interestingly no difference was found between insulin dependent and noninsulin dependent diabetics. Diabetics are also at risk of failure of fixation in the postop- erative period as a result of reduced proprioceptive joint control (Charcot neuroarthropathy). Patients may not be inhibited suf- ficiently by pain, and neuromuscular control of joint stability may be impaired resulting in greater forces being transferred to the fracture fixation leading to mechanical failure. This neuroar- thropathy is common in diabetics 366 and frequently the diagno- sis is only made postoperatively. 173 Patients presenting late with ankle fractures have a higher rate of Charcot changes (64%) than those presenting early (22%). 157