American College of Foot and Ankle Surgeons^® Clinical Consensus Statement: Perioperative Management

Believing that the creation of CCSs would be beneficial to its members, the ACFAS enacted an initiative to create such documents for foot and ankle surgeons. This initiative was originally conceived to report on a variety of topics and to replace previous clinical practice guidelines (, , , , , , ). To move forward with this initiative, a formal consensus method process was undertaken. Seven experts in the field of foot and ankle surgery were initially sent an invitation by the ACFAS to participate on a panel to develop a CCS on “perioperative management.” A 5-member panel was eventually convened and tasked with reviewing the published medical data and providing opinions about this topic. The panel was chaired by 1 member (A.J.M.) and assisted by ACFAS members and staff. During a several-month period, the panel members participated in an electronic mail dialog, conference calls, and a face-to-face meeting. The stated goal of the panel was to develop a series of CCS questions on the topic of perioperative management that might be of interest and value to foot and ankle surgeons, examine the current published data relating to these statement questions, and synthesize this information and our consensus opinions for ACFAS members and The Journal of Foot and Ankle Surgery^® readers.

Our first task was the development of a series of CCS questions for inclusion. The topic of perioperative management is broad, and any number of subtopics and specific statement questions could be derived from it. Initially, through ACFAS member survey feedback, our collective clinical experience, and the results of an open discussion during an introductory conference call, we developed a preliminary list of approximately 35 to 40 specific topics within the realm of perioperative management to consider as consensus statement questions for inclusion in this CCS. The panel members subsequently performed preliminary data reviews and wrote brief synopses on these topics, attempting to answer the questions of (1) whether any guidelines exist on this topic; (2) whether any original investigations have been reported on this topic specific to the foot and ankle; and (3) whether any other original investigations have been reported on this topic specific to other medical specialties, but still potentially relevant. On a subsequent conference call, these initial reviews and synopses were discussed, and the panel made majority decisions resulting in the inclusion and development of 22 CCS questions (Table).

Comprehensive reviews of the published data were then performed by the panel members and included searches of Medline^®, EMBASE^®, the Cochrane Database of Systematic Reviews, and manual searches of the references of the included articles. Although this was not a formal systematic review, each panel member conducted thorough literature searches using these databases in an attempt to answer specific questions on each topic. The data searches included at least all prospective clinical trials, retrospective clinical cohort analyses, and retrospective case series specifically involving foot and ankle surgery on the respective topics.

A modified Delphi method was then used to attain consensus on the clinical questions by the members of the panel (). The series of 22 statement questions was developed by the panel chairperson and sent to all panel members to review and answer. The answers were determined by the appropriateness of the statement question and were graded from 1 (extremely inappropriate) to 9 (extremely appropriate) using a Likert scale (). Each panel member initially answered the questions anonymously, and the results were returned to the panel chairperson. The answers were reviewed, analyzed, and grouped from 1 to 3 (inappropriate), 4 to 6 (neither inappropriate nor appropriate), and 7 to 9 (appropriate). The results were summarized with basic descriptive statistics, kept anonymous, and distributed back to the panel members. At the face-to-face meeting, the questions and initial consensus results were reviewed and opened to discussion. Although an attempt was made to reach consensus for all questions, it was not a requirement, and, in fact, contrary opinions were encouraged. All panel members participated in the creation of the CCS manuscript, the final draft of which was subsequently submitted to the ACFAS leadership for adoption and to The Journal of Foot and Ankle Surgery^® for publication.

Although it is likely that most foot and ankle surgical procedures should be considered low perioperative risk, for a number of situations our panel concluded that perioperative risk could increase to an elevated risk category.

Patient perioperative risk is traditionally thought of in objective terms as the development of a major adverse cardiac event (MACE) and, unsurprisingly, determining this risk is a complex and multifactorial process. Recent guidelines published by the American College of Cardiology and the American Heart Association defined a “low risk” procedure as one in which the risk of a MACE is <1%, and an “elevated risk” procedure is one in which the risk of MACE is ≥1% (). Note that the terms “moderate risk” and “high risk” were not used, and, instead, the term “elevated risk” was used to describe any procedure with risk of a MACE of ≥1%.

Determining this risk is both patient and procedure dependent. In terms of procedure-specific considerations, surgeries have conventionally been categorized into “high-risk procedures” (including but not limited to intrathoracic procedures, intraperitoneal procedures, and some peripheral vascular surgeries), “intermediate-risk procedures” (including, but not limited to, head and neck surgery, major neurologic surgery, major orthopedic surgery, endovascular procedures, pulmonary procedures, major urologic procedures, and so forth), and “low-risk procedures” (including minor orthopedic procedures, dental procedures, breast procedures, minor urologic procedures, and so forth) (). These categories carry a corresponding estimated risk of a MACE of approximately >5%, 1% to 5%, and <1% (). Although no clear objective definition of the difference between a “major” and “minor” orthopedic procedure is available, as a reference, total hip and knee arthroplasty procedures are generally considered “major” (). It is likely that most osseous foot and ankle specific procedures would be considered “minor orthopedic surgery”; however, several procedures (i.e., tibiotalocalcaneal arthrodesis with intramedullary reaming, total ankle arthroplasty, Charcot reconstruction) could be argued to rise to the level of “major orthopedic surgery.” Furthermore, foot and ankle limb preservation procedures can be performed in conjunction with higher risk endovascular procedures or open arterial bypass. The specific type of anesthetic technique used would also be expected to influence the procedure-dependent risk.

In terms of patient-specific considerations, several classification systems can be used to assist physicians in objectifying risk. Perhaps the most common is the American Society of Anesthesiologists (ASA) physical status (PS) classification, which defines normal healthy patients as type 1, patients with mild systemic disease as type 2, patients with severe systemic disease as type 3, patients with severe systemic disease that is a constant threat to life as type 4, moribund patients who are not expected to survive the operation as type 5, and patients who have been declared brain dead but undergoing organ harvest as type 6 (). The ASA PS also includes a type E prefix for patients undergoing emergency procedures. A degree of subjectivity exists between type 2 “mild systemic disease” and type 3 “severe systemic disease.” Conventionally “mild” conditions are “well-controlled” and “severe” conditions are “uncontrolled” (). This might be most applicable with respect to the foot and ankle when considering the diagnoses of diabetes mellitus and hypertension. Although it is not uncommon for published case series to include ASA PS information within the patient demographic data, we identified 1 study specific to the foot and ankle that had evaluated the “safety” of an anesthetic technique (). Their review examined 110 consecutive ASA PS level 3 and 4 patients undergoing limb preservation surgery, which speaks to the potential scenario of performing foot and ankle surgery on relatively high ASA PS patients.

Although the ASA PS classification is widely recognized and used, several other systems might offer a greater degree of specificity. The American College of Surgeons National Surgical Quality Improvement Program has developed a risk calculator with an online component (available at: http://riskcalculator.facs.org/). This risk calculator takes into account the type of procedure (using the Current Procedural Terminology code) and a number of patient factors, including age, functional status, ASA class, steroid use, systemic sepsis within 48 hours of surgery, the presence of diabetes, the presence of hypertension requiring medication, previous cardiac event, the presence of congestive heart failure, the presence of dyspnea, smoking history, a history of chronic obstructive pulmonary disease, the need for dialysis, the presence of acute renal failure, and body mass index (BMI) (). The calculator then produces an objective number for the estimated risk of a serious complication, any complication, pneumonia development, a cardiac complication, a surgical site infection (SSI), a urinary tract infection, venous thromboembolism, renal failure, a return to the operating room, death, discharge to a rehabilitation facility, and the predicted length of stay. For example, a 65-year-old male with a history of insulin-dependent diabetes, hypertension, smoking, and obesity undergoing an emergency bimalleolar ankle fracture with open reduction and internal fixation (ORIF) carries a 10.0% risk of a serious complication, a 12.1% risk of any complication, a 1.3% risk of a cardiac complication, and a 0.8% risk of death. This, again, at least speaks to the potential for foot and ankle surgery to carry an elevated risk. Another resource with an online calculator is the revised cardiac risk index (available at: http://www.mdcalc.com/revised-cardiac-risk-index-for-pre-operative-risk/). This also provides an objective measurement of estimated cardiac risk by accounting for high-risk versus intermediate- or low-risk procedures, a history of ischemic cardiac disease, a history of congestive heart failure, a history of cerebrovascular disease, creatinine level, and preoperative treatment with insulin (). Both of these tools emphasize the broader point that the term “medical clearance” for the operating room is a misnomer. All surgeries are associated with some perioperative risk, and the goal of a preoperative medical evaluation should be to objectify the risk, with the understanding that the risk can never be completely eliminated.

If it is accepted that a “low-risk” procedure is one in which the incidence of a MACE is <1%, we can conclude that most, but not all, foot and ankle surgical procedures are likely to be low risk.Consensus statement: The panel reached consensus that the statement “Foot and ankle surgeons should use specific hair removal and preoperative skin bathing protocols before elective foot and ankle surgical procedures” was neither appropriate nor inappropriate.

We identified no consensus within our panel for a clear benefit or detriment to specific hair removal and/or bathing protocols before elective foot and ankle surgery. The panel did not conclude that these techniques were inappropriate; rather, we did not identify a clear positive or negative effect to support consistent implementation of specific preoperative measures.

The preoperative removal of hair from the surgical field is a practice that has been used for many years as a method to decrease the potential for surgical site contamination and, therefore, SSIs. However, contemporary debate has ensued over the effectiveness of hair removal in decreasing SSIs and an increasing body of evidence of some possible negative effects that hair removal might have as it relates to postoperative complications. Evidence on this topic has primarily been derived from other surgical specialties and not specifically from the foot and ankle specialty. A 2011 Cochrane review on preoperative hair removal found “no statistically significant effect on surgical site infection rates” (). In another meta-analysis of 19 randomized controlled trials, shaving with a razor was significantly associated with a more frequent occurrence of SSIs compared with clipping, chemical depilation, or no hair removal (). Another comparative analysis evaluated patients undergoing general surgery procedures, specifically comparing hair removed with a razor to hair removed with a depilatory cream and found a significant difference in postoperative infection rates (12.8% versus 2.5%, respectfully) (). An increasing number of opponents to using a razor for hair removal have argued that it disrupts the normal skin flora homeostasis, can disrupt the bacteria present in hair follicles, and that the use of contaminated razors could lead to postoperative infection (). We concluded that hair can likely be safely removed preoperatively, although preferably with a clipper or depilation cream and not a razor.

Similarly, the practice of preoperative bathing or skin cleansing before the formal surgical preparation is a commonly performed practice that does not appear to have clear supporting evidence of a substantial benefit. A prospective cohort study was reported within the foot and ankle literature evaluating the effects of a single preoperative chlorhexidine foot bath 20 minutes before elective foot surgery and revealed a decrease in positive culture results but no difference in the incidence of SSIs between the control and intervention groups (). Another Cochrane review of 10,157 participants did not demonstrate substantial evidence for preoperative showering or bathing with chlorhexidine compared with other products such as soap to reduce the incidence of SSIs (). Additionally, a separate meta-analysis reviewed 16 trials with 17,932 patients and found that chlorhexidine bathing did not reduce the incidence of SSIs compared with detergent, soap, placebo, or no bathing protocol ().Consensus statement: The panel reached consensus that the statement “Preoperative methicillin-resistant Staphylococcus aureus decontamination protocols should be performed before elective foot and ankle surgical procedures” was neither appropriate nor inappropriate.

Although a fair amount of clinical evidence supports preoperative methicillin-resistant Staphylococcus aureus (MRSA) decontamination protocols before elective surgery, our panel did not reach consensus that this was universally appropriate for the foot and ankle. The panel did not conclude that these techniques were inappropriate but also did not identify a clear positive or negative effect of consistently implementing this specific preoperative measure.

This is a topic that on the surface would appear to make intuitive sense. Several sources, including the Centers for Disease Control and Prevention have recognized that preoperative colonization with S. aureus (SA) is a risk factor for the development of a SSI (, , ), and this might be even more applicable for those colonized with MRSA. Kalra et al () found that rates of MRSA SSI development were significantly greater in those preoperatively colonized with MRSA compared with those not colonized (1.86% versus 0.20%; p < .0001). Both Kalra et al () and Gupta et al () found an approximate 9 times greater odds of developing a MRSA SSI in those preoperatively colonized with MRSA. Furthermore, a substantial percentage of patients undergoing lower extremity orthopedic surgery are likely to be colonized with either SA and/or MRSA. An investigation by Price et al () of 284 patients undergoing orthopedic surgery, including the foot and ankle, found that 86 (30%) were colonized with either SA or MRSA. Although 30% is a substantial proportion of patients, we believe it is important to note that this still represents a minority of patients.

However, despite knowledge that some of our patients might be colonized with SA and MRSA and that this might increase the risk of a postoperative infection, preoperative decolonization protocols might not have a significant preventative effect on the development of a SSI. In the study by Price et al (), low rates of SSI were observed whether or not the patients were colonized and whether or not the patients underwent decolonization. Additionally, the investigators did not identify a specific risk with procedures involving the foot and ankle. In another study of patients undergoing elective orthopedic surgery, Kim et al () did not find a significant difference between SSI rates among noncarriers (0.14%) and MSSA carriers (0.19%). In another prospective study of patients undergoing cardiac, hip, or knee surgery, no significant differences were noted in SSI rates among patients who had undergone a decontamination process (0.20% rate of infection) compared with those not undergoing decontamination (0.35% rate of infection) ().

In contrast, other studies seem to point toward a positive effect of screening and decontamination protocols. Hacek et al () studied 912 patients who were screened before hip or knee replacement, 75% of whom were negative for SA colonization and demonstrated a 0.6% rate of infection. The 25% of patients who were SA carriers and underwent decontamination before surgery had a 1.3% rate of infection. The SSI rate for the patients who were neither screened nor treated was 1.7%. Chen et al (, ) in 2013 recommended decolonization for patients undergoing total joint replacement because of the significant reduction in MRSA infection after decontamination (4.6% decreased to 0%).

Although studies have advocated the use of decontamination in cardiac, spinal, and total joint replacement procedures, little conclusive evidence is available to support the universal use of such practices in general or for the foot and ankle specifically. Certainly, some reduction in postoperative infection rates might occur when SA or MRSA carriers undergo decontamination; however, this might not always be statistically or clinically significant. Moreover, in our review of the published data, decontamination protocols often varied considerably among practices and hospitals. Many of the protocols recommended the use of intranasal mupirocin twice daily for 5 days, with chlorhexidine showers for 5 days before surgery (, , , , , , ). Other protocols involved used mupirocin for 5 days, but chlorhexidine bathing was used for 1 day before surgery (). We did not identify a specific “standard of care” decontamination protocol and it would likely be difficult to develop one owing to the variations in patient populations and microbiologic demographics.Consensus statement: The panel reached consensus that the statement “Cigarette smoking should be considered a risk factor for the development of complications after foot and ankle surgical procedures” was appropriate.

The numerous negative effects of cigarette smoking on the physiology of the human body, in addition to the increased perioperative risks of patients who smoke, have been well documented (, , , , , , ). This is primarily due to the effects of nicotine and carbon monoxide resulting in vasoconstriction, decreased microperfusion, decreased tissue oxygenation, endothelial damage, increased blood viscosity, and hypercoagulation (). We reached consensus that tobacco use in the form of cigarette smoking should be considered a risk factor for the development of complications after foot and ankle surgical procedures and that patients who smoke should be educated on the potential complications of this activity before undergoing foot and ankle surgery.

We identified several investigations examining foot and ankle surgical outcomes in relation to cigarette smoking. Krannitz et al () found that in active smokers, a distal first metatarsal osteotomy for the surgical correction of hallux abductovalgus required 1.73 times longer to radiographically heal compared with nonsmokers. In another investigation examining elective forefoot surgery, smokers were 4.3 times as likely to develop any complication and demonstrated greater rates of delayed union, infection, delayed wound healing, and persistent postoperative pain compared with nonsmokers (). Furthermore, increased rates of wound complications and infection have been associated with smoking in patients after ORIF of calcaneal fractures () and ankle fractures (, ). Greater nonunion rates in smokers were also observed after subtalar arthrodesis ().

What might be less certain is the effect of preoperative smoking reduction or cessation on surgical outcomes. A study evaluating patients undergoing general surgery and total joint arthroplasty demonstrated that smoking cessation 4 weeks before surgery and extending for 4 weeks after surgery resulted in an overall decrease in complications by 20% (). Another study evaluating patients undergoing hip and knee arthroplasty revealed a decrease in all postoperative complications by 34% and a decrease in wound-related complications by 26% after a 6- to 8-week preoperative smoking cessation protocol (). In an investigation evaluating incisional healing after cutaneous biopsy, smoking cessation 4 weeks before the procedure significantly decreased the rate of infection (). That study also suggested that the duration of smoking cessation of 4, 8, or 12 weeks did not show any significant difference in terms of the occurrence of postoperative infection. Additionally, a study of colorectal patients showed no effect on the postoperative complication rate when the smoking cessation programs were initiated <4 weeks in advance ().

We concluded that substantial evidence exists that cigarette smoking is associated with postoperative complications after foot and ankle surgery and that, as a profession, we should relay these risks to our patients. A survey of the British Orthopaedic Foot and Ankle Society revealed that only 9% of surgeons documented the smoking habits of their patients on consent forms and warned them of the risk of potential complications and only 23% reported taking any preventative perioperative measures (). Although we cannot conclude that a smoking history is an absolute contraindication to a specific foot and ankle surgery, our consensus is that tobacco use should be considered a relative risk factor for the development of complications. Patients should be educated regarding the specific risks of tobacco use, and, when possible, smoking should be stopped at least several weeks before the performance of elective foot and ankle surgical procedures.Consensus statement: The panel reached consensus that the statement “Elevated body mass index should be considered a risk factor for the development of complications after foot and ankle surgical procedures” was neither appropriate nor inappropriate.

Obesity has been described as a global epidemic, and its effect on the development of some foot and ankle pathologic features is well established (, , , , , , , , , , , , ). However, the specific effect of obesity on complications after foot and ankle surgical procedures is less certain. We identified little evidence of an absolute contraindication to foot and ankle surgery in the setting of patient obesity or a BMI threshold over which specific foot and ankle surgical procedures should not be performed. However, the conclusion of our panel was that the presence of an elevated preoperative BMI is likely to carry at least some degree of risk for the development of some postoperative complications, including a thrombotic event, postoperative infection, and postoperative wound healing complications. This increased risk should be recognized and appreciated by both the surgeon and the patient.

Although many investigations have evaluated the association of BMI and surgical complications in their secondary analyses (, , , , , , , , , , , , ), we identified 20 studies with hypotheses specifically addressing the effect of obesity on lower extremity surgery (, , , , , , , , , , , , , , , , , , , ). These included studies on total ankle arthroplasty, pilon fracture ORIF, ankle fracture ORIF, calcaneal fracture ORIF, ankle arthrodesis, Achilles tendon repair, ankle arthroscopy, flatfoot reconstruction, and elective forefoot reconstruction. Interestingly, 9 of these studies showed an association of obesity with the development of postoperative complications, including postoperative wound complication, postoperative infection, the need for revision surgery, the loss of articular reduction, an increased operative time, longer healing times, implant failure, decreased implant survival, venous thromboembolism, an increased length of stay, and general medical complications (including pulmonary embolism, myocardial infarction, respiratory failure, cerebral vascular event, pneumonia, acute renal failure, cholecystitis) (, , , , , , , , ), but the remaining 11 investigations did not show such an association (, , , , , , , , , , ).

Several of these studies involved database analyses with relatively large cohorts, and we observed that those larger studies tended to show the development of postoperative complications in the obese. Burrus et al () reviewed 18,948 patients undergoing Achilles tendon repair. Of those, 2962 were obese. The study found a greater rate of postoperative wound complication, postoperative infection, and other medical complications in the obese group. Werner et al () reviewed 23,029 patients undergoing total ankle arthroplasty or ankle arthrodesis and found that obese patients were more likely to experience postoperative infection, postoperative stiffness, and a range of medical complications. Bostman et al () found that a greater BMI was associated with a loss of reduction requiring reoperation in 3061 patients undergoing ankle ORIF. Chen et al () observed that obese patients were more likely to require revision hallux abductovalgus surgery in a series of 452 participants. In contrast, however, Stewart et al () found no difference in outcomes associated with obesity in a series of 633 forefoot surgeries.

This is an area in which our profession will likely learn more in the future and appears to be of contemporary interest to investigators, because most studies we identified specifically examining the effect of obesity on surgical outcomes have been published within the past 5 years. We also believe that it is important to note that although it is possible that obesity has a direct effect on surgical outcomes, it is also possible that obesity simply serves as a surrogate for other confounding factors.Consensus statement: The panel reached consensus that the statement “An elevated glycated hemoglobin should be considered an independent risk factor for the development of complications after foot and ankle surgical procedures” was appropriate.

The association between hyperglycemia and postoperative complications has been well documented after many types of surgical procedures (, , , , , , , , , , ). Poor long-term glucose control, as measured by glycated hemoglobin, has been recognized as a risk factor for the development of adverse outcomes after major surgeries, such as vascular and coronary artery procedures (, , , ). In the foot and ankle specifically, poorly controlled and complicated diabetes has also been shown to be significant risk factors for both postoperative soft tissue and bone healing complications (, , , , , , , , ). Surgeons should be aware of this when recommending and performing foot and ankle surgery, and our patients should also be made aware that this increases the potential for postoperative complications. We also recommend that foot and ankle surgeons perform glycated hemoglobin measurement before performing elective surgery. It should be noted that this is in contrast to a random glucose measurement, which might be influenced by a variety of preoperative stresses and other factors.

Myers et al () have shown an association between an elevated glycated hemoglobin level and postoperative infection after hindfoot and/or ankle arthrodesis. Younger et al () also found that the most significant factor associated with successful transmetatarsal amputation in diabetic patients was blood glucose control measured by the glycated hemoglobin. They compared the mean glycated hemoglobin levels between a failed and successful group in their retrospective study of 42 patients. The mean level in the failed group was 10.6% and that of the successfully healed group was 7.8%. Lepore et al () evaluated patients admitted to the hospital for foot ulceration. In their cohort study, patients who had undergone major amputation, minor amputation, and no amputation were compared in terms of glycated hemoglobin level. They found that patients who had undergone amputation had a significantly greater glycated hemoglobin level than did those who had not undergone amputation. In particular, those who had undergone major amputation had a mean glycated hemoglobin level of 10% and those with minor amputation or no amputation had a mean glycated hemoglobin level of 9% and 8%, respectively. Humphers et al () investigated whether the glycated hemoglobin level was independently associated with postoperative complications in a retrospective cohort study. After adjusting for other covariates, they found that the glycated hemoglobin level was independently associated with postoperative soft tissue complication, including infection and wound dehiscence. Jupiter et al () assessed the relationship between the glycated hemoglobin levels and the rate of postoperative infection in the foot and ankle. They explored the general trends relating to the infection rates and preoperative glycated hemoglobin levels (). Their preliminary analysis indicated that infection rates increased as the glycated hemoglobin level increased to 7.3% but increased rapidly with glycated hemoglobin values of 7.3% to 9.8% before leveling off.

The incidence of bone healing complications in diabetic patients is also high after foot and ankle surgeries (, , , , , , , ). Although this association of hyperglycemia has been well documented (, , , , , , , , , ), little clinical information is available regarding which diabetes-related comorbidities directly affect bone healing at a biochemical level. Shibuya et al () showed that approximately 1 of 4 diabetic patients had ≥1 bone healing complications. A bone healing complication was defined as ≥1 of nonunion, malunion, delayed union, or surgical- or trauma-induced Charcot neuroarthropathy. They found that a patient with a glycated hemoglobin level >7% had roughly 3 times greater odds of developing a bone healing complication than those with a glycated hemoglobin level <7%.

Most often in studies assessing the effect of long-term glycemic control on postoperative outcomes, the glycated hemoglobin level is used as the metric for control. Comparing well-controlled versus poorly controlled diabetics, many use a cutoff level of 7% to categorize good versus poor control, based on the American Diabetes Association recommendation. The American Diabetes Association recommendation is derived from several studies assessing intensive glycemic control therapy in reducing the long-term complications associated with diabetes, including the Diabetic Control and Complications Trial Research Group (DCCT), UK Prospective Diabetes Study (UKPDS), Action in Diabetes and Vascular Disease: Preterax and Diamicron Modified Release Controlled Evaluation (ADVANCE), Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial, and Veterans Affairs Diabetes Trial (VADT) (, , , , , ). Summarizing these findings, the benefits of lowering the glycated hemoglobin level in patients with diabetes in terms of the reduction of diabetes-related macro- and microvascular complications appear to be substantial. However, in decreasing the glycated hemoglobin level to <7%, the benefits seem to diminish, and a risk also exists of adverse events (including death, weight gain, and hypoglycemic episodes) in this range. It should also be noted that intensive glycemic control could be a risk itself, especially in a chronically uncontrolled diabetic patient population. Caution should be taken when attempting aggressive preoperative hyperglycemic control.

As recommended by many, including the American Diabetes Association, a glycated hemoglobin threshold of 7% is known to be a relatively good reference point, at least in terms of general health (). However, definite evidence on foot and ankle-specific surgical procedures is still lacking. Furthermore, we believe it is important to note that an absolute threshold line might also depend on the type of procedure to be performed. Our panel concluded that elevated glycated hemoglobin values should be considered a risk factor for the development of complications after foot and ankle surgical procedures, that foot and ankle surgeons should check the glycated hemoglobin value before recommending and performing elective surgery in patients with diabetes, and that patients with an elevated glycated hemoglobin level should be made aware of their specific perioperative risks. However, we do not recommend a specific glycated hemoglobin threshold for the performance of elective foot and ankle surgical procedures.Consensus statement: The panel reached consensus that the statement “A high preoperative blood glucose level should be considered a risk factor for the development of complications after foot and ankle surgical procedures” was neither appropriate nor inappropriate.

Although exceedingly abnormal preoperative serum glucose levels are a general contraindication for elective surgery, little evidence is available to support that it has a consistent and direct effect on foot and ankle surgical outcomes. The reason that it might not be as robust a predictor as the glycated hemoglobin value might be because serum glucose levels can be affected by multiple factors, such as nil per os (or “nothing by mouth”) status, surgical stress, and other day of surgery medications (, ). It should also be noted that an attempt to rapidly decrease an elevated serum glucose level on the day of surgery could result in hypoglycemia and increased cardiovascular risk (, ). In general, intensive glucose control and a low serum glucose level could be more harmful than a moderately elevated serum glucose level on the day of the surgery in diabetic patients (, , ).

We recognize that several studies have demonstrated an increased occurrence of SSIs associated with high preoperative serum glucose levels (, , , ) but concluded that high serum glucose levels on the day of surgery might primarily be a confounder for poor long-term glycemic control. Therefore, one should understand that although the perioperative glucose level is unstable, sensitive, and easily affected by many factors on the day of surgery, it should primarily raise a concern regarding the patient's long-term glucose control and other underlying medical conditions. We identified no definitive evidence of a threshold value for the serum glucose level over which foot and ankle surgical procedures should not be performed.

Additionally, some emergency situations exist in which the risk of delaying surgery outweighs the risk of performing the operation with a high preoperative serum glucose level. In the management of abscess and cellulitis, for example, the elevated glucose level might be due to the infection itself; thus, the serum glucose level cannot be easily managed without surgical debridement, incision, and drainage. The anesthesia and surgical risks should be discussed among the surgical team in these situations.Consensus statement: The panel was unable to reach consensus on the statement “Vitamin D levels should be assessed before all foot and ankle arthrodesis procedures.”

The panel was unable to reach consensus on the routine assessment of vitamin D levels before elective foot and ankle arthrodeses. The members of the panel who believed this was an inappropriate practice pointed to evidence demonstrating a high prevalence of hypovitaminosis D in acute fractures and other cohorts of otherwise “normal” individuals (, , , , ). Although the positive effects of vitamin D combined with calcium supplementation in fracture prevention in an elderly population has been well established (, , ), the effect of vitamin D on bone healing after injury or surgical intervention has not been as extensively studied. Although some studies have indicated a high incidence of vitamin D deficiency in patients with nonunion, these studies have often lacked a control group for comparison (, ). Even less evidence is available to show that normalization of serum vitamin D in a deficient patient can assist in the prevention or treatment of nonunion. Therefore, it is uncertain whether a routine preoperative serum vitamin D evaluation is indicated before foot and ankle surgical procedures for assessment of bone healing potential and prevention of nonunion.

Further evidence has been provided by Haining et al (), who compared the vitamin D levels in 15 patients with nonunion with 15 age- and gender-matched controls. The serum 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D₃, and 24,25-dihydroxyvitamin D₃ levels were compared between these 2 groups (). They did not show any difference in the vitamin D levels between the nonunion and the matched control groups (). Boszczyk et al () conducted a case-controlled, cross-sectional study comparing the prevalence of vitamin D deficiency between patients with an idiopathic fracture healing impairment versus patients without such a complication. A total of 35 patients from each group were enrolled in their retrospective study. No differences were observed in the prevalence of vitamin D deficiency between the 2 groups. The overall prevalence of hypovitaminosis D was 86% in their cohort. Pourfeizi et al () compared the serum vitamin D levels in tibial nonunion cases and normal union cases. Their case-control study enrolled the control group from normal union patients matched by treatment type, age, gender, and BMI. They were considered vitamin D deficient when the serum 25-hydroxyvitamin D level was <23 nmol/L. They found that the prevalence of vitamin D deficiency was 30% in the matched control group and was 60% in the nonunion group. Ravindra et al () in their longitudinal study of 133 elective spinal fusions in the United States showed no association between vitamin D deficiency (serum 25-dihydroxyvitamin D level <20 ng/mL) and nonunion on bivariate analysis. However, it became an independent factor (odds ratio 3.5) for nonunion after adjusting for age, fusion length, and gender in a multiple regression analysis. In their cohort, 21 of the 133 patients (16%) were patients with nonunion. Nine of the 21 patients in this group had a vitamin D deficiency. They also showed that the median time to union was significantly longer in the vitamin D-deficient group on Kaplan-Meier survival analysis. Doetsch et al () in a randomized clinical trial examined the effect of vitamin D and calcium supplementation (oral 800 IU of vitamin D₃ and 1 g of calcium) on osteoporotic proximal humerus fracture healing. They found that the mineral density of the shoulder in the group with vitamin D and calcium supplementation was significantly greater statistically at 6 weeks. No difference was found at other time points (0, 2, and 12 weeks).

Because many patients in the control groups of these and other investigations have vitamin D deficiency, the incidence of this deficiency is also believed to be high in the normal population (). Because of this, the results have been mixed in assessing the association of vitamin D deficiency and bone healing complications in the available case-control studies. Furthermore, no substantial evidence is available that supplementation of vitamin D positively affects bone healing after foot and ankle surgery. Further still, vitamin D deficiency is known to confound with many factors, such as older age, BMI, smoking, and heart and vascular diseases (, , , ). The case-control studies accounted for some of these factors; however, it is difficult to control for all the variables without randomization.

The members of the panel who believed this was an appropriate practice argued that vitamin D deficiency could also affect aspects of postoperative outcomes other than bone healing (, , , , ). Warner et al () showed significantly lower clinical outcomes, as evidenced by the Foot and Ankle Outcome Score, after ORIF of ankle fractures in those patients with a preoperative vitamin D level <20 ng/mL. Lee et al () found that more patients experienced moderate to severe pain after knee arthroplasty when deficient in vitamin D.

Additionally, evidence has shown an association of vitamin D and bone healing in the published data (, , , , , , , ). Vitamin D is crucial for ideal bone formation and metabolism and overall health (, , ). Vitamin D deficiency has been linked to several health issues, including cardiovascular disease, cancer, autoimmune diseases, diabetes mellitus, hypertension, and multiple sclerosis (, , ). In addition, vitamin D deficiency has been associated with specific bone metabolic diseases, including osteoporosis, osteomalacia, and poor bone growth. Vitamin D deficiency has also been cited as a common cause of stress fracture development and poor fracture healing (, , ).