Patients with diabetes are no strangers to dealing with the complications associated with their disease. As foot and ankle surgeons, we also often face the challenge of treating the complications and sequelae of this pathologic process including lower extremity deformity, non-healing wounds, Charcot neuroarthropathy and infection to name a few.
However, what happens when we, as intervening medical professionals, are the cause of a relatively predictable complication? What about when a patient with diabetes at increased risk for complication requests elective surgery? Is it our obligation to treat these patients as we do those without diabetes or should we approach these patients with a more wary and conservative eye? In other words, when is it okay to say “no” to a patient with diabetes?
Although these are certainly questions without definitive answers, a review of recent literature may help podiatric surgeons make relatively judicious decisions. There are times when the medical profession may be a little too eager to please and when it seems like patients can always find a surgeon who will say “yes.” In a similar way, it can sometimes be difficult to remember that it is not our primary job to please our patients but instead to diagnose, educate and recommend. Just because a patient is willing to entertain increased perioperative surgical risk does not mean that we have to as well. It is okay to say “no.”
There is an increasing body of evidence that one should reconsider elective surgical intervention in the setting of uncontrolled hyperglycemia, both in terms of short-term and long-term control. Perhaps one can most easily appreciate this with long-term control of the hemoglobin A1c value. It can sometimes be frustrating in clinical practice when patients cannot recall their value or, even worse, have no knowledge of what it designates. At least in our practice, this laboratory test is part of the standard preoperative evaluation and we will not make a specific surgical recommendation to a patient with diabetes who does not have knowledge of this number.
A natural question that follows is “how high is too high?” in terms of the hemoglobin A1c. Although we do not have a definitive answer for this question, the literature continues to demonstrate a significantly increased risk of surgical complications with surprisingly small increases in the hemoglobin A1c.
Wukich and colleagues demonstrated that patients with diabetes with complications were 10 times as likely to develop a postoperative infection following foot and ankle surgery in comparison to patients without diabetes.1 The authors also found that patients with diabetic complications were six times as likely to develop postoperative infection in comparison to patients with diabetes without complications. Myers and colleagues subsequently found a significantly higher postoperative infection rate in patients with an A1c higher than 7% in comparison to patients lower than 7% in a series of ankle and hindfoot fusions.2
Shibuya and coworkers found that patients with a hemoglobin A1c higher than 7% were approximately three times as likely to have a bone healing complication in comparison to those with a hemoglobin A1c less than 7%.3 A recent investigation on over 1,700 patients undergoing total joint arthroplasty found that patients with an A1c value higher than 6.7% were nine times as likely to develop a postoperative wound complication.4
Short-term control of blood glucose also likely has an impact on perioperative results although this has not been as well investigated yet. A recent study from the University of Michigan found that preoperative blood glucose measurements above even 120 mg/dL in patients undergoing neurosurgical operative interventions led to an increased risk of postoperative complications and longer lengths of hospital stay.5 In the lower extremity, researchers found a statistically significant increased risk of wound dehiscence in those with preoperative glucose measurements higher than 200 mg/dL (and in patients with hemoglobin A1c higher than 6.5%).6
Although these and other results push our profession closer to specific recommendations, they do not provide specific “cutoff” values. In our practice, we give serious pause and often cancel elective surgery in patients with preoperative hemoglobin A1c values more than 8% and/or blood glucose values higher than 200 mg/dL. Indeed, we often wonder if these cutoffs are too high. We hope that by educating our patients on the additional risks and complications inherent to uncontrolled diabetes, they may aim to better control their glucose prior to undertaking elective surgery.
Even with all the general knowledge today about smoking and its overall negative effects on human physiology, an estimated 45.3 million adults in the United States smoke.7 The adverse effects of smoking in the lower extremity are primarily a result of nicotine’s vasoconstrictive properties that subsequently lead to decreased tissue perfusion and oxygenation.8 Not only does smoking increase wound healing complications but it also affects bone healing.
There are multiple studies that demonstrate increased nonunion rates among smokers in various foot and ankle procedures.9-14 A prospective, multicenter study of 268 patients reported smokers to be 37 percent more likely to develop nonunions in comparison to nonsmokers.13 Chahal reported that smokers were 3.8 times more likely than nonsmokers to have a nonunion in regard to subtalar joint arthrodeses.14 Krannitz and colleagues found that not only was there increased time to radiographic healing among smokers in Austin bunionectomies, they also found a correlation between urine cotinine levels and increased time to healing.15
Although research definitively shows increased wound and bone complications in smokers, many foot and ankle surgeons continue to perform elective surgery on patients with diabetes who smoke. Smoking is an absolutely modifiable risk factor. One should educate patients on the effects of smoking and encourage them to quit. When the additional predisposition of micro- and macrovascular disease in patients with diabetes is compounded with the vasoconstrictive properties of smoking, it can cause devastating outcomes for elective surgery.
In the United States, there is a strong link between diabetes and obesity, objectively defined as an increased body mass index (BMI) over 30. With the rise of obesity and its own inherent risk factors, diabetes can only add to the list of a patient’s potential complications. Patients with diabetes already face an uphill battle with wound and bone healing. With the added effects of obesity come more complications including anesthesia difficulties, deep venous thrombosis (DVTs) and difficulty maintaining appropriate non-weightbearing status throughout the postoperative recovery period.
By itself, BMI is an objective patient finding that is known to correlate with perioperative and long-term patient morbidity and mortality.16-23 Obese patients have worse clinical and surgical outcomes following the development of lower extremity pathology.24-38 This is a modifiable risk factor that patients can change through dedicated diet, exercise and education.
The preoperative evaluation of patients with diabetes should include a BMI calculation as well as a goal BMI for surgical intervention in some cases. If diet and exercise are not sufficient or improbable, patients can seek medical attention from primary care physicians, bariatric surgeons and a host of support groups. The orthopedic community has relative obesity cutoffs for total joint arthroplasty procedures of the knee and hip. Why wouldn’t our profession follow suit for foot and ankle reconstructions?
The preceding lists the three most common situations in which we tell our patients with diabetes no but the list is certainly not representative of all situations. We also tell patients with diabetes no when our podiatric surgical interventions will not lead to an appreciable increase in functional outcome and/or when there is little potential for healing in cases of critical limb ischemia for examples. We wish that we could tell you we always stick to our guns but the fact of the matter is that we all will at least occasionally take unnecessary risks with our surgical recommendations.
In regard to diabetic foot surgery, although we may try to make the best recommendations for our patients and we may try to educate them as specifically as possible with respect to the potential risks and complications, there are certainly times when it is easier to “yes” and more difficult to say “no.” We need to be stronger in those situations instead of looking to assign responsibility to the patient.
It is a physician’s duty to provide patients with the best possible outcomes and there are many situations when this may involve knowing when to say “no.” Elective surgery is just that: elective. In contrast to certain trauma and infections, we can schedule elective surgery when the patient has been optimized for the best surgical outcome or even not at all. This is particularly true with patients with diabetes and it is all of our responsibility to continue to define and learn the risks inherent to this disease process.
Dr. Pirozzi is a fourth-year Chief Resident with the Temple University Hospital Podiatric Surgical Residency Program at Temple University Hospital in Philadelphia.
Dr. Meyr is an Associate Professor in the Department of Podiatric Surgery at the Temple University School of Podiatric Medicine in Philadelphia.
1. Wukich DK, Lowery NJ, McMillen RL, Frykberg RG. Postoperative infection rates in foot and ankle surgery: a comparison of patients with and without diabetes mellitus. J Bone Joint Surg Am. 2010; 92(2):287-95.
2. Myers TG, Lowery NJ, Frykberg RG, Wukich DK. Ankle and hindfoot fusions: comparison of outcomes in patients with and without diabetes. Foot Ankle Int. 2012; 33(1):20-8.
3. Shibuya N, Humphers JM, Fluhman BL, Jupiter DC. Factors associated with nonunion, delayed union, and malunion in foot and ankle surgery in diabetic patients. J Foot Ankle Surg. 2013; 52(2):207-211.
4. Stryker LS, Abdel MP, Morrey ME, Morrow MM, Kor DJ, Morrey BF. Elevated postoperative blood glucose and preoperative hemoglobin A1c are associated with increased wound complications following total joint arthroplasty. J Bone Joint Surg Am. 2013; 95(9):808-14.
5. Davis MC, Zlewacz JE, Sullivan SE, El-Sayed AM. Preoperative hyperglycemia and complication risk following neurosurgical intervention: A study of 918 consecutive cases. Surg Neurol Int. 2012; 3:49.
6. Endara M, Masden D, Goldstein J, Gondek S, Steinberg J, Attinger C. The role of chronic and perioperatie glucose management in high risk surgical closures; a case for tighter glycemic control. Plast Reconstr Surg. 2013 Jun 18 Epub.
7. Available at http://www.cdc.gov/tobacco/data_statistics/fact_sheets/adult_data/cig_sm...  . Published June 5, 2013. Accessed Dec. 3, 2013.
8. Jensen JA, Goodson WH, Hopf HW, Hunt TK. Cigarette smoking reduces tissue oxygen. Arch Surg 1991; 126(9):1131-1134.
9. Easley M, Trnka HJ, Schon, LC, Myerson MS. Isolated subtalar arthrodesis. J Bone Joint Surg Am. 2000; 82(5):613-24.
10. Cobb TK, Gabrielsen TA, Campbell DC 2nd, Wallrichs SL, Ilstrup DM. Cigarette smoking and nonunion after ankle arthrodesis. Foot Ankle Int. 1994; 15(2):64-7.
11. Adams CI, Keating JF, Court-Brown CM. Cigarette smoking and open tibial fractures. Injury. 2001; 32(1):61-5.
12. Ishikawa SN, Murphy GA, Richardson EG. The effect of cigarette smoking on hindfoot fusions. Foot Ankle Int. 2002; 23(11):996-8.
13. Castillo RC, Bosse MJ, MacKenzie EJ. Fracture healing and risk of complications in limb-threatening open tibia fractures. J Orthop Trauma. 2005; 19(3):151-7.
14. Chahal J, Stephen DJG, Bulmer B, Daneils T, Kreder HJ. Factors associated with outcome after subtalar arthrodesis. J Orthop Trauma 2006; 20(8):555–561.
15. Krannitz KW, Fong HW, Fallat LM, Kish J. The effect of cigarette smoking on radiographic bone healing after elective foot surgery. J Foot Ankle Surg. 2009; 48(5):525-527.
16. Felcher AH, Mularski RA, Mosen DM, Kimes TM, DeLoughery TG, Laxson SE. Incidence and risk factors for venous thromboembolic disease in podiatric surgery. Chest. 2009; 135(4):917-22.
17. Dodson NB, Ross AJ, Mendicino RW, Catanzariti AR. Factors affecting healing of ankle fractures. J Foot Ankle Surg. 2013; 52(1):2-5.
18. Shibuya N, Frost CH, Campbell JD, Davis ML, Jupiter DC. Incidence of acute deep vein thrombosis and pulmonary embolism in foot and ankle trauma: analysis of the National Trauma Data Bank. J Foot Ankle Surg. 2012; 51(1):63-8.
19. Graves ML, Porter SE, Fagan BC, Brien GA, Lewis MW, Biggers MD, Woodall JR, Russell GV. Is obesity protective against wound healing complications in pilon surgery? Soft tissue envelope and pilon fractures in the obese. Orthopedics. 2010; 33(8).
20. Japour C, Vohra P, Giorgini R, Sobel E. Ankle arthroscopy: follow-up study of 33 ankles—effect of physical therapy and obesity. J Foot Ankle Surg. 1996; 35(3):199-209.
21. Bostman OM. Body-weight related to loss of reduction of fractures of the distal tibia and ankle. J Bone Joint Surg Br. 1995; 77(1):101-3.
22. Friedman RJ, Hess S, Berkowitz SD, Homering M. Complication rates after hip or knee arthroplasty in morbidly obese patients. Clin Orthop Relat Res. 2013; 471(10):3358-66.
23. Greenblatt DY, Rajamanickam V, Mell MW. Predictors of surgical site infection after open lower extremity revascularization. J Vasc Surg. 2011; 54(2):433-9.
24. Weil L Jr. Obesity, feet, and the impact on health care. Foot Ankle Spec. 2012; 5(3):148-9.
25. Butterworth PA, Landorf KB, Smith SE, Menz HB. The association between body mass index and musculoskeletal foot disorders: a systematic review. Obes Rev. 2012; 13(7):630-42.
26. Runhaar J, Koes BW, Clockaerts S, Bierma-Zeinstra SM. A systematic review on changed biomechanics of lower extremities in obese individuals: a possible role in development of osteoarthritis. Obes Rev. 2011; 12(12):1071-82.
27. Shultz SP, Sitler MR, Tierney RT, Hillstrom HJ, Song J. Consequences of pediatric obesity on the foot and ankle complex. J Am Podiatr Med Assoc. 2012; 102(1):5-12.
28. Bostman OM. Prevalence of obesity among patients admitted for elective orthopaedic surgery. Int J Obes Relat Metab Disord. 1994; 18(10):709-13.
29. Fabris SM, Faintuch J, Brienze SL, Brito GB, Sitta IS, Mendes EL, Fonseca IC, Cecconello I. Are knee and foot orthopedic problems more disabling in the superobese? Obes Surg. 2013; 23(2):201-4.
30. Finkelstein EA, Chen H, Prabhu M, Trogdon JG, Corso PS. The relationship between obesity and injuries among U.S. adults. Am J Health Promot. 2007; 21(5):460-8.
31. Wearing SC, Hennig EM, Byrne NM, Steele JR, Hills AP. Musculoskeletal disorders associated with obesity: a biomechanical perspective. Obes Rev. 2006; 7(3):239-50.
32. Kessler J, Koebnick C, Smith N, Adams A. Childhood obesity is associated with increased risk of most lower extremity fractures. Clin Orthop Relat Res. 2013; 471(4):1199-207.
33. Chaudhry S, Egol KA. Ankle injuries and fractures in the obese patient. Orthop Clin North Am. 2011; 42(1):45-53.
34. Moayyeri A, Luben RN, Wareham NJ, Khaw KT. Body fat mass is a predictor of risk of osteoporotic fracture in women but not in men: a prospective population study. J Intern Med. 2012; 271(5):472-80.
35. Sohn MW, Budiman-Mak E, Lee TA, Oh E, Stuck RM. Significant J-shaped association between body mass index (BMI) and diabetic foot ulcers. Diabetes Metab Res Rev. 2011; 27(4):402-9.
36. Stuck RM, Sohn MW, Budiman-Mak E, Lee TA, Weiss KB. Charcot arthropathy risk elevation in the obese diabetic population. Am J Med. 2008; 121(11):1008-14.
37. Vela SA, Lavery LA, Armstrong DG, Anaim AA. The effect of increased weight on peak pressures: implications for obesity and diabetic foot pathology. J Foot Ankle Surg. 1998; 37(5):416-20.
38. Armstrong M. Obesity as an intrinsic factor affecting wound healing. J Wound Care. 1998; 7(5):220-1.