Current Insights In Treating Diabetic Foot And Ankle Trauma

The management of diabetic foot and ankle injuries has raised significant debate and controversy over the last few years. Unfortunately, there is still no clear consensus on treatment protocols that necessitate surgical intervention. The main reason for this controversy is because there is no single correct way of treating even the most commonly encountered diabetic foot and ankle fractures and/or dislocations.

   The treating surgeon needs to be able to provide the most successful management and avoid potential inherent complications that are common in the diabetic population. A wide spectrum of injuries can occur that include neuropathic and non-neuropathic fractures, dislocations or both. In addition, concomitant soft tissue injuries present further unique challenges for overall surgical management.

Evaluating And Addressing The Compromised Soft Tissue Envelope

The foot and ankle have a limited amount of soft tissue coverage. Therefore, one needs to pay particular attention to minimizing wound healing complications when managing diabetic injuries. When it comes to patients with diabetes, one needs to ensure medical optimization in order to avoid any potential effects from diabetes, anemia, cardiac, renal, vascular and/or pulmonary disease. The presence of multiple comorbidities can have a deleterious outcome on the wound and bone healing process, and further complicate the patient’s overall medical status throughout the treatment course.

   The utilization of supplementary oxygen to prevent tissue hypoxia and appropriate glucose control are some measures one can initiate in order to reduce the risks of infection and wound healing complications.

   Successful management of diabetic foot and ankle trauma is dependent on detailed knowledge of the vascular anatomy of the foot, ankle and lower extremity. Understanding the boundaries of each angiosome of the foot and ankle, and how it relates to its source artery provides the basis for logical surgical incisions. When treating this patient population, surgeons need to understand that a source artery may be occluded secondary to peripheral vascular disease or trauma, which may lead to a compromised angiosome.

   Accordingly, podiatrists may need to utilize Doppler ultrasound, basic non-invasive vascular studies or pursue further vascular imaging and intervention preoperatively in order to determine if definitive fixation through planned incisions is feasible. A plan for definitive treatment may become challenging when multiple or extensile incisions are required to achieve the necessary osseous reconstruction desired.

   Often, surgeons may need to stage incisions and their associated procedures in order to prevent postoperative skin necrosis and deep infection. Examples of this concept include the use of limited incisions to perform percutaneous plating and/or internal fixation, use of only external fixation, or employing a combination of the two to achieve fracture reduction while minimizing soft tissue compromise.

   In certain situations, it may be better to utilize staged procedures that allow for more direct incisions once the patient’s lower extremity edema subsides. An example of this concept is the management of diabetic calcaneal intra-articular comminuted fractures. In the diabetic patient with a compromised soft tissue envelope, it may be preferable to obtain initial reduction of the calcaneal fracture with external fixation and stage a primary subtalar joint arthrodesis as opposed to performing an open reduction and internal fixation through an extensile lateral incision.

   During the initial management of diabetic foot and ankle injuries, it is important to consider the underlying osseous injury and its role in contributing to both vascular and/or soft tissue compromise. When it comes to severe deformities to the lower extremity, one may need to reduce the deformity in an urgent manner and determine if vascularity to the lower extremity has improved in order to prevent devastating soft tissue compromise or loss of the limb. In these cases, appropriate consultation to the vascular team may also be necessary at the early stages of treatment.

   It is common for surgeons to apply a spanning “temporary” external fixator for the management of diabetic injuries with compromised vascularity and/or soft tissue envelope. One can utilize the efficiency of a simple “bar to clamp” external fixation apparatus to manage severe acute osseous foot and ankle deformities that are posing a risk to the surrounding soft tissue envelope. The use of a spanning external fixator is paramount to provide fracture reduction and osseous stability while promoting early healing of any soft tissue injuries that are present.

   This type of fixation can also facilitate any plastic and/or vascular surgery procedures that may need to be performed. It can also allow one to closely monitor for any signs of a compartment syndrome.

   The management of open diabetic foot and ankle fractures is even more challenging. It is often best to treat these fractures with serial debridements followed by delayed primary closure or flap coverage. In rare case scenarios, you may see a simple wound which is not contaminated and can be closed with no tension. With these wounds, one can perform thorough irrigation of the wounds and subsequent primary closure.

   However, repeat debridements and irrigations of the open wound may be necessary to further reduce the risk of infection and soft tissue compromise in comparison to uncontaminated wounds that one can close in a primary fashion in the patient with diabetes.

Key Surgical Considerations In Patients With Insensate Diabetic Foot And Ankle Injuries

In formulating a surgical plan, a multitude of factors should influence the procedure selection and surgical technique. The presence of dense peripheral neuropathy, morbid obesity, peripheral vascular disease, smoking history and poor soft tissue envelope often lead to a specialized treatment plan in order to reduce the risk of potential postoperative complications.1-11

   Insensate diabetic foot and ankle injuries require not only absolute osseous stability of the fractured segments or dislocated joints, but stabilization of adjacent joints as well to further prevent pathologic forces that can contribute to a post-op Charcot neuroarthropathy event. Some of the most common treatments surgeons would consider in these situations may include:
• the application of a neutralizing external fixation device in addition to the internal fixation;
• further supplementation of the fixation of the ankle with trans- or extra-articular large Steinmann pins;
• increasing the fixation by utilizing longer plates or double plating techniques;
• the use of bridge plating techniques for midfoot trauma; or
• a primary arthrodesis for the severely comminuted intra-articular fractures.

   Surgeons may utilize various internal fixation techniques for the management of diabetic foot and ankle trauma. Certainly, one does not have to treat every diabetic injury with the aforementioned surgical techniques. When it comes to patients with well controlled diabetes and a lack of other previously discussed comorbidities, you may employ surgical techniques that are common to utilize for foot and ankle trauma in general. Despite the surgical techniques being similar to achieve fracture reduction, longer immobilization and protected weightbearing, once initiated, are highly recommended. In addition, follow-up visits are usually more frequent to closely monitor the patient’s recovery and postoperative adherence issues.

Exploring The Options For Enhanced Stability

The combination of external fixation with internal fixation is often an excellent way of ensuring stability of the diabetic neuropathic lower extremity. One may manage fractures and/or dislocations in a typical fashion and apply either a spanning or circular external fixation to further stabilize the joints. This is typically the case with talar fractures or extrusions, and severely open midfoot, ankle or pilon fractures and/or dislocations.

   Often, even after you have achieved an anatomic reduction, instability may still be present secondarily to severe disruption of the joint capsule and the surrounding ligamentous structures. The surgeon may utilize spanning “delta” external fixation to temporarily stabilize the ankle and rearfoot. Extensions to the forefoot may also be needed to further stabilize any associated midfoot trauma. Surgeons commonly apply a circular external fixation device if they need to manipulate any osseous segments or estimate that the time in the external fixator will exceed six to eight weeks.8-11

   Transarticular fixation is another method to prevent late joint subluxation and/or further stabilize a severe diabetic foot and ankle fracture. The advantage of Steinmann pins is to provide supplementary fixation across unstable ankle fractures in addition to internal fixation.

   One may also use these pins as a primary means of fracture reduction. This technique can be useful for diabetic ankle fractures in geriatric patients or diabetic ankle fractures and/or dislocations that are not amenable to internal fixation due to either severe peripheral vascular disease or soft tissue compromise.3,4

   Surgeons may use multiple internal fixation plates for severely comminuted distal tibia or pilon fractures. Double plating offers increased stability and helps neutralize deforming forces that may occur over the prolonged time it takes for the osseous segments to heal. As in any other case, it is important to minimize soft tissue dissection and maintain the periosteum near the fracture fragments, and only consider multiple plates if the soft tissue envelope is not compromised. Preserving the periosteum is paramount.

   The insertion of multiple internal fixation products must be meticulous. At times, the surgeon may need to place these plates percutaneously. The ultimate goal is to achieve adequate fracture reduction and osseous stability while minimizing any vascular insult to the surrounding soft tissue envelope.

   When it comes to patients with diabetic neuropathy, primary arthrodesis is usually indicated for unstable midfoot neuropathic fractures and/or dislocations, neglected fractures, and pulverized intra-articular fractures.11 Primary arthrodesis of the midfoot is advantageous for the management of complete ligamentous dislocations or comminuted intra-articular fractures, and to further avoid hardware failure, late collapse and an incidence of a Charcot neuroarthropathy.

   For example, one may need to perform a medial column arthrodesis for a neuropathic navicular comminuted fracture. Severe fracture patterns that are not amenable to reconstruction are better to stabilize initially with an external fixator in order to enhance the overall alignment of the osseous segments and in preparation of a staged salvage arthrodesis. One often sees this with certain high-energy pilon and calcaneal fractures.

In Conclusion

Despite the most appropriate surgical management, many diabetic foot and ankle injuries may still have a poor prognosis. For this reason, careful evaluation and incorporation of a healthcare team with knowledge in the overall treatment of diabetes mellitus and its related complications are essential for the patient’s successful recovery.

   Dr. Stapleton is an Associate in Foot and Ankle Surgery at VSAS Orthopaedics in Allentown, Pa. He is a Clinical Assistant Professor of Surgery at the Penn State College of Medicine in Hershey, Pa.

   Dr. Zgonis is an Associate Professor, Fellowship Director and Chief of the Division of Podiatric Medicine and Surgery within the Department of Orthopaedics at the University of Texas Health Science Center at San Antonio. He is the Founder and Co-Chairman of the International External Fixation Symposium (IEFS), which is held annually in December in San Antonio.

References

1. Chaudhary SB, Liporace FA, Gandhi A, Donley BG, Pinzur MS, Lin SS. Complications of ankle fracture in patients with diabetes. J Am Acad Orthop Surg 2008;16(3):159-70.
2. Wukich DK, Kline AJ. The management of ankle fractures in patients with diabetes. J Bone Joint Surg Am 2008;90(7):1570-8.
3. Jani MM, Ricci WM, Borrelli J Jr, Barrett SE, Johnson JE. A protocol for treatment of unstable ankle fractures using transarticular fixation in patients with diabetes mellitus and loss of protective sensibility. Foot Ankle Int 2003; 24(11):838-44.
4. DiDomenico LA, Brown D, Zgonis T. The use of Ilizarov technique as a definitive percutaneous reduction for ankle fractures in patients who have diabetes and peripheral vascular disease. Clin Podiatr Med Surg 2009; 26(1):141-148.
5. Ramanujam CL, Facaros Z, Zgonis T. Perioperative management of the dysvascular foot and ankle. Perioperative Nursing Clinics 2011;6(1):17-26.
6. Kline AJ, Gruen GS, Pape HC, Tarkin IS, Irrgang JJ, Wukich DK. Early complications following the operative treatment of pilon fractures with and without diabetes. Foot Ankle Int 2009;30(11):1042-7.
7. Wukich DK, Joseph A, Ryan M, Ramirez C, Irrgang JJ. Outocomes of ankle fractures in patients with uncomplicated versus complicated diabetes. Foot Ankle Int 2011; 32(2); 120-30.
8. Marin LE, DiDomenico LA, Stamatis ED, Zgonis T. Diabetic neuropathic pilon and ankle osseous trauma and dislocations. In: Zgonis T (ed): Surgical Reconstruction of the Diabetic Foot and Ankle. Lippincott Williams & Wilkins, Philadelphia, Pa., 2009, pp. 357-374.
9. Marin LE, DiDomenico LA, Mandracchia VJ, Zgonis T. Diabetic neuropathic forefoot, midfoot and hindfoot osseous trauma and dislocations. In: Zgonis T (ed): Surgical Reconstruction of the Diabetic Foot and Ankle. Lippincott Williams & Wilkins, Philadelphia, Pa., 2009, pp. 344-356.
10. Facaros Z, Stapleton JJ, Polyzois VD, Zgonis T. Management of foot and ankle trauma. Perioperative Nursing Clinics 2011;6(1):35-43.
11. Facaros Z, Ramanujam CL, Zgonis T. Primary subtalar joint arthrodesis with internal and external fixation for the repair of a diabetic comminuted calcaneal fracture. Clin Podiatr Med Surg 2011;28(1):203-209.

   For further reading, see “Proactive Measures To Prevent Diabetic Complications” in the October 2005 issue of Podiatry Today, “How To Treat Ankle Fractures In Patients With Diabetes” in the April 2006 issue or “Do Trauma Patients With Diabetes Face Higher Complication Rates?” in the October 2007 issue.