DIABETICS AND ORTHOPAEDICS
From The 7th Biennial Canadian Orthopaedic Foot and Ankle Symposium
| SURGICAL MANAGEMENT OF MIDFOOT AND HINDFOOT CHARCOT ARTHROPATHY —Sheldon
S. Lin, MD, Associate Professor of Medicine, University of Medicine and Dentistry of New Jersey, Newark
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| Significance of diabetes: 20 million cases in United States; estimated 600,000 new cases annually (50% undiagnosed)
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| Charcot arthropathy: noninfective destruction of bone and joint; patients with diabetes at risk for ulceration
and lower extremity amputation; study—237 patients followed for 10 yr; 50% required surgical intervention
(major or minor amputation; fusion; exostectomy); proposed etiologies—hypovascularity; repetitive trauma;
neuropathy; combined instability and neuropathy; clinical presentation—acute injury, eg, sprain; immobilizing
neuropathic patients after acute traumatic event recommended
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| Classification system: based on clinical and radiographic changes; 3 phases—acute phase (dissolution); healing
phase (convalescence); healed phase (resolution); lasts 12 to 18 mo; useful for—counseling patients; timing
of surgical reconstruction
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| Clinical problems: difficulty in shoe wear; alteration in plantar pressure; increased risk of ulceration and
lower extremity amputation
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| Nonsurgical treatment: total-contact cast (TCC) for 3 to 4 mo (change weekly first 2 to 3 wk, then every
other week); ankle-foot orthosis (AFO) or Charcot restraint orthotic walker (CROW) for 12 to 18 mo (possibly
lifetime); consider advancing patient to extra-depth footwear and custom total contact insole (TCI)
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| Surgical treatment: indications—severe deformity not amenable to custom brace; marked instability; recurrent
ulceration; goals—to obtain alignment and stability; to prevent amputation; to achieve braceable plantar
grade foot (not to make brace-free); contraindications—infection of bone or soft tissue; patient in acute phase;
uncontrolled diabetes; peripheral vascular disease (PVD); insufficient bone stock; patient unable to comply
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| Dilemma of reconstruction on patient with Charcot: cons—high risk (“headaches” for surgeon); technical
difficulties; pros—reduced energy expenditure with more distal (or no) amputation; avoidance of bilateral
amputation
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| Timing of surgery: in resolution stage; ulceration present—heal with TCC protocol; then rule out underlying
osteomyelitis with combined leukocyte-labeled indium scan and Tc99-pertechnetate (Tc99-scan)
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| Surgical techniques: hindfoot reconstruction—tibiocalcaneal arthrodesis (using blade plate); fusion with intramedullary
(IM) rod (allows more stability but requires shifting calcaneus medially); triple arthrodesis (eg,
for subtalar fracture-dislocation); midfoot reconstruction—internal fixation (with plantar plate)
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| Key points on surgical reconstruction: long-term reconstruction; 3 to 4 mo non-weight-bearing in TCC; 1
to 2 mo weight-bearing in TCC; 12 to 18 mo (or lifetime) in CROW or bivalved AFO
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| Results of reconstruction: meta-analysis (143 patients; 8 clinical series; bone union successful in 70%; 87%
able to ambulate with brace); speaker’s series (of 27 patients, 26 rendered stable and able to wear brace);
conclusion—modern techniques and appropriate immobilization increase union rate and decrease complications
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| Potential adjuncts: tight glucose control of diabetes (improves bone healing); ultrasonography (accelerates
bone healing 30%); internal bone stimulation
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| ADVANCED THERAPIES FOR DIABETIC FRACTURES —Dr. Lin
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| Impaired healing in diabetes: study found time to union prolonged 163%; distal tibial fractures healing time
3.6 mo without diabetes vs 8.2 mo with diabetes; high incidence of complications, delayed union, and impaired
bone healing
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| Factors underlying problem: speaker’s investigation—fracture healing in rat model for diabetes; found impaired
chondrogenesis in diabetic group at 7 days and 4 wk; mechanical findings impaired at 6 to 8 wk; almost
50% reduction of cells in diabetic callus; growth factors in fracture hematoma—contain osteogenic
potential; include fibrin, blood cells, platelets, and plasma; critical growth factors reduced in diabetic
hematoma—platelet-derived growth factor (PDGF)- β 50% at day 4; insulin-like growth factor (IGF)-1 50% at
day 4; vascular endothelial growth factor (VEGF) 65% at day 7; speaker’s findings in patients with diabetes—
measured growth factor levels in hematoma ≈14 days after fracture; PDGF 160 pg/mL vs 275 pg/mL in nondiabetic;
PDGF- β 375 pg/mL vs 8500 pg/mL in nondiabetic
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| Clinical applications: growth factors available to orthopaedic surgeon:
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 | Platelet-rich plasma (PRP): autologous platelet concentrate includes PDGF, PDGF- β, VEGF, epidermal
growth factor (EGF), and IGF; using centrifuge method or filtration method, commercially available systems
process patient’s blood at point of care in 10 to 15 min; study findings—prospective randomized trial in
dental literature showed trabecular bone growth 55% with bone graft alone vs 74% with combined bone
graft and PRP; in speaker’s study of fusion, high-risk patients (smokers and diabetics; mean age 51 yr) established
union at 45 days with bone graft alone vs 40 days with PRP (overall union rate ≈94%); controlled
study after ankle surgery compared fusion rate with bone graft alone vs bone graft with PRP (61% vs 76% at
8 mo; 73% to 94% at 12 mo; 85% to 97% at 6 mo; in smokers, union rate 50% with bone graft alone vs 80%
with PRP and bone graft
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| Recombinant bone morphogenic protein (BMP): infused BMP-2; osteogenic protein (OP)-1; BMP-7; implanted
periosteally, induces new bone formation
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| Cost: PRP using centrifuge method $400 to $500, using filtration method $700; BMP $4000 to $5000 per application
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| Approved applications: PRPP classified as blood transfusion (nonregulated); infused BMP-2 approved for
open tibia fractures; OP-1 and BMP-7 received humanitarian device exception for long-bone nonunion
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| Conclusion: other agents in development; augmentation with growth factors may ameliorate impaired healing
in diabetes
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| DEBATE: WHAT IS THE ORTHOPAEDIC SURGEON’S ROLE IN THE MANAGEMENT OF DIABETIC
NEUROPATHIC FOOT DISEASE?
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Timothy R. Daniels, MD, Associate Professor, Department of Surgery, Division of Orthopaedic Surgery, University
of Toronto Faculty of Medicine, Toronto, ON
| Introduction: speaker assumes role of general orthopaedic surgeon overwhelmed with difficulties of managing
diabetic patients; in practice with 4 other orthopaedists
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| Surgeon’s attitude and concerns: enjoys hip and knee surgery; “but I don’t like the diabetic foot because I
don’t understand it”; patients do not care for themselves during life, then expect surgeon to take care of problem;
concerned about spreading infection from diabetic wounds to patients with implants
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| Examples of frustrating problems: inability to diagnose and treat swollen foot risk for amputation; lacks access
to specialized surgical instruments; does not understand what specialists mean by “Aquinas contracture”;
after taking time to counsel patient about shoe wear, patient presents with improper shoes, risking further toe
amputations; cause of foot ulceration unknown; unable to employ total contact casts; patients cannot afford
brace
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| Conclusion: appeal for help in managing difficult problems
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Alistair S.E. Younger, MD, Instructor, Department of Orthopaedics, University of British Columbia Faculty of
Medicine, Vancouver
| Introduction: requires basic orthopaedic skills; educate and counsel patients in managing problem
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| Superficial ulceration: maximize nonoperative treatment, eg, orthotics, patient education, diabetic control;
may consider gastrocnemius slide
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| Deep infection: debride ulcer; if probe passes deep to dermis, operation required; further testing unnecessary
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| Infection prevention: preventing and healing ulcers key; surgery essential but small part of treatment; team
approach—requires involvement of endocrine, internal medicine, and infectious disease specialists
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| Glucose control essential: treatment destined to fail if not achieved; does not require orthopaedic foot and ankle
specialist; necessary before operating; example of patient before and after glucose control—following surgery
for Charcot fracture, infection led to below-knee amputation; later, after glucose controlled, Charcot
midfoot fracture treated successfuly with orthotics; originally, hemoglobin (Hb)A1c 11%; later, HbA1c 7%;
patient realized life depended on controlling glucose; patients told before surgeon will operate—must have
HbA1c <8%; must stop smoking
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| Simple operations: gastrocnemius slide; percutaneous Achilles tendon lengthening; transmetatarsal amputation;
toe amputation; tenotomy
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| Conclusion: managing diabetic complications almost as expensive as orthopaedic trauma; goals of surgery to—
reduce cost of treatment; preserve mobility; preserve independence; maintain patient in community
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| PANEL DISCUSSION —Drs. Lin, Daniels, and Younger
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| Vascularity and healing: Dr. Lin—obtains preoperative arterial Doppler study; “as long as the ankle-brachial
index (ABI) is greater than, I think, 0.45,” patient able to achieve wound healing and fusion; “not a major
issue”; Dr. Younger—glucose control central issue; “microvascular disease a bit of a myth”; based on
earlier assumption that damage identified by pathologists affected oxygen supply to tissues; subsequent
studies found no evidence that microvascular disease in diabetes affects oxygen delivery to tissues; clinical
findings due to structural deformity and soft tissue contractures combined with metabolic effects of diabetes
on ability to repair tissue
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| Glucose control and surgery: Canadian Institute for Health Information (CIHI) criteria for reducing surgical
infection rate (preoperative antibiotic prophylaxis; correct shaving of area; postoperative glucose control);
postoperative glucose control requires preoperative glucose level; speaker advocates ruling out reconstructive
surgery when HbA1c >8%; wound breakdown develops when HbA1c >10% (reduced leukocyte level impedes
ability to fight infection); glucose control also required to avoid wound breakdown after hip and knee replacement;
Dr. Younger—failure to control “epidemic” could threaten all orthopaedic care; goes beyond care of
diabetic foot and ankle; increased long-term care of diabetic patients reduces bed space available for other orthopaedic
patients
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Educational Objectives
| The goal of this program is to educate the listener about managing foot and ankle problems in patients with diabetes.
After hearing and assimilating this program, the orthopaedic surgeon will be better able to:
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| 1. Manage midfoot and hindfoot Charcot arthropathy in diabetic patients requiring surgery.
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| 2. Employ growth factors in platelet-rich plasma in managing fractures in patients with diabetes.
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| 3. Diagnose and treat foot ulceration in diabetic patients.
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| 4. Recognize the importance of adequate glucose control in the management of orthopaedic problems in patients
with diabetes.
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| 5. Prevent and treat infection and wound breakdown in diabetic orthopaedic patients.
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Suggested Reading
Bonnarens F et al: Production of a standard closed fracture in laboratory animal bone. J Orthop Res2:97,
1984; Deresh GM et al: Reconstruction of the diabetic Charcot foot incorporating bone grafts. J Foot Ankle
Surg 35:474, 1996; Edmonds ME et al: Diabetic foot ulcers. BMJ 332:407, 2006; Edmonds ME: Progress in
care of the diabetic foot. Lancet 354:270, 1999; Edmonds ME: The diabetic foot, 2003. Diabetes Metab Res
Rev 20 Suppl 1:S9, 2004; Gandhi A et al: The effects of local platelet rich plasma delivery on diabetic fracture
540-546. Bone; Lavery LA et al: Disease management for the diabetic foot: effectiveness of a diabetic foot
prevention program to reduce amputations and hospitalizations. Diabetes Res Clin Pract 70:31, 2005; Loder
RT: The influence of diabetes mellitus on the healing of closed fractures. Clin Orthop Relat Res:210, 1988;
LoGerfo FW et al: Current management of the diabetic foot. Adv Surg 30:417, 1996; Most RS et al: The epidemiology
of lower extremity amputations in diabetic individuals. Diabetes Care 6:87, 1983; Mueller MJ et
al: Effect of Achilles tendon lengthening on neuropathic plantar ulcers. A randomized clinical trial. J Bone Joint
Surg Am 85-A:1436, 2003; Myerson M et al: The total-contact cast for management of neuropathic plantar ulceration
of the foot. J Bone Joint Surg Am 74:261, 1992; Timlin M et al: Fracture hematoma is a potent proinflammatory
mediator of neutrophil function. J Trauma 58:1223, 2005.
Faculty Disclosure
In adherence to ACCME guidelines, the Audio-Digest Foundation requests all lecturers to disclose any significant
financial relationship with the manufacturer or provider of any commercial product or service discussed.
The following has been disclosed: Dr. Lin—Tournier (consultant); DePuy (research)
Drs. Lin, Daniels, and Younger were recorded at the 7th Biennial Canadian Orthopaedic Foot & Ankle Symposium
, sponsored by the Canadian Orthopaedic Foot and Ankle Society and by the Faculty of Medicine, University
of Toronto, held in Toronto, ON, April 8-9, 2006. The Audio-Digest Foundation thanks the speakers and
the sponsor for their cooperation in the production of this program.
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