Is Osteomyelitis Primarily A Surgical Disease?
Yes, Dr. Dujela points to key principles and case studies that convey the need for surgical treatment in facilitating curative results. The notion that osteomyelitis is “primarily” a surgical disease does not discount the importance of adjunctive antibiotic therapy. However, in the presence of established osteomyelitis, surgical treatment should be the mainstay with antibiotics playing a supporting role. The basic philosophy in the surgical treatment of osteomyelitis is foot salvage. Essentially, we are attempting to achieve a balance between resecting adequate bone for curative results while maintaining sufficient bone and structure for stability. Three general goals of treatment for osteomyelitis and infections should guide our therapy. • Facilitate an optimum environment and physical characteristics for soft tissue and bone healing. • Strive for a functional and plantigrade foot. • Preserve as much of the functional foot as possible. While I am a proponent of surgical treatment and limb salvage in osteomyelitis, I recognize that patients are sometimes better served by a definitive and healed amputation that allows ambulation and resumption of daily living activities. For some patients, this is more appropriate than leaving someone incapacitated by prolonged non-weightbearing, total contact casting or chronic wound care regimens to save a marginally viable segment of the foot. One Case Study To Consider While I was a resident, I had the opportunity to work with an overweight diabetic patient whose husband had severe chronic obstructive pulmonary disease. She had chronic MRSA osteomyelitis of the calcaneus secondary to a longstanding heel ulceration. She was often seen towing her wheezing husband in a wheelchair caboose-style with her power scooter 20 mph through the corridors of the hospital. The patient was initially treated with long term IV antibiotics and wound care as an outpatient. The infection progressed and she was treated with a partial calcanectomy. The chief resident had written an order for complete postoperative bed rest. Two hours after surgery, during her period of complete bed rest, she fractured the remaining segment of her calcaneus while returning to bed after a “cigarette break.” After prolonged IV antibiotic therapy and difficult wound management, the patient was treated with a total calcanectomy after refusing an amputation. Initially, she did quite well, but after some time had passed, the osteomyelitis, which had partially affected her midfoot, overwhelmed her and she finally agreed to have an amputation. Within two months, she returned to the office 30 pounds lighter. She wore a prosthesis and was ambulating for the first time in over a year. She proudly presented us with a batch of homemade cookies (that the residents fondly called “MRSA bombs”) and told us that she should have had the surgery months before. It’s important to recognize that physicians and patients often spend a great deal of energy and resources trying to salvage an extremity that is beyond preservation. In some cases, one should view amputation as the most conservative option in treating osteomyelitis. What You Should Know About The Location Of The Infection It’s also essential to consider the location of the infection as it plays a key role in choosing the appropriate therapy. For example, osteomyelitis frequently occurs with digital ulcerations. Keep in mind that phalangeal bone infections are rarely cured by antibiotics alone and usually require partial or complete amputation. Osteomyelitis of the sesamoids is another cause of chronic non-healing wounds that generally do not respond to IV therapy. Osteomyelitis of the metatarsals often requires surgical treatment via bone debridement or ray resections. Surgical treatment often alleviates the deformity that caused the ulceration and eventual bone infection. Consider the common hallux interphalangeal joint ulceration. Reduction of this prominence via a Villaneuva procedure or an IPJ arthroplasty often not only results in surgical cure of the osteomyelitis but diminishes the risk of recurrence. Many other examples of this scenario occur in the foot such as a plantar first metatarsal head ulceration or collapsed medial column with navicular prominence in Charcot osteoarthropathy. One can often perform primary closure or early delayed primary closure that allows earlier return to function and alleviates the need for long-term wound care. Prolonged periods of antibiotic therapy for osteomyelitis is often standard for these patients. Unfortunately, the standard six-week benchmark for parenteral therapy was determined largely by experience with childhood hematogenous osteomyelitis. This prolonged period of antibiotic therapy may not be necessary or appropriate in the more common direct extension or contiguous focus osteomyelitis of adults. Why Ensuring Appropriate Patient Selection Is Critical Who are the most common podiatric patients affected by osteomyelitis? You may see patients who have an infected non-union or a direct extension open fracture, but often it is the diabetic population that is susceptible to osteomyelitis. Often these patients receive sub-therapeutic suppressive doses of antibiotics secondary to renal compromise. How well do they fare on months of antibiotic therapy? How effective is this? Aren’t patients who are deemed poor candidates for surgery often equally poor candidates for months of antibiotics? In all cases, we should consider the vascularity and the patient’s ability to mount an immune response. Most surgical failures in treating osteomyelitis are due to vascular insufficiency. It’s essential to consider the diabetic patient with osteomyelitis carefully. For example, foot complications are not always related to the severity of the disease. Consider the paradox of gangrene in the presence of palpable pulses. Things are not always as they appear. When Failed Antibiotic Therapy Makes A Tough Case More Difficult Another case that comes to mind involved a 60-year-old diabetic female who had a Charcot rocker-bottom foot deformity and typical plantar cuboid ulceration. An infectious disease physician had treated her with long-term IV antibiotics based on bone culture. After two and a half weeks, the patient developed persistent spiking fevers and did not have any improvement in the foot. We obtained a cardiology consult and a transesophalgeal echocardiogram revealed what we had feared: bacterial endocarditis. After additional antibiotic therapy and aggressive surgical debridement of the foot, the endocarditis cleared, the wound drainage ceased and the patient was able to return to full time work without any further problems. This proved to be another case of failed antibiotic therapy that converted a fairly ordinary yet challenging podiatric scenario into an extraordinary one. A Key Pearl For Ensuring Curative Results When treating osteomyelitis, we must focus on preserving viable soft tissue and avoiding the common pitfall of resecting too much viable soft tissue while failing to resect adequate bone. During the surgical procedure, one should obtain adequate bone specimens for culture and sensitivity to guide therapy. Then you should also obtain a proximal specimen or an additional portion of bone with a clean saw blade. Send this additional specimen for culture and histologic analysis. If there is no bacterial growth, inflammation or marrow edema in the “clean” specimen, you may forgo long term adjunctive IV antibiotic therapy. Armed with this information as well as the clinical appearance, you may be comfortable considering this a surgical cure. It may then be treated as a soft tissue infection. In this case, aggressive surgical therapy dramatically decreases or eliminates the need for postoperative antibiotics. Again, osteomyelitis is primarily a surgical disease. Longstanding osteomyelitis, particularly sequestra, will not respond to antibiotics without surgical therapy. It is optimal to perform aggressive staged debridement or an “en bloc” resection while allowing an interval for soft tissue rest and recovery under the protection of good nutrition, adequate blood flow and antibiotic assistance. A move toward reconstruction may include performing free tissue transfer such as free flap or autogenous grafting. Static or dynamic external fixation, such as Ilizarov, is also a viable and important adjunct. Again, chronic osteomyelitis may be suppressed by antibiotic therapy but it is generally not cured in the absence of surgical measures. Final Points My partner, John McCord, DPM, sums it up well: “If you treat osteomyelitis with antibiotics alone, you probably aren’t doing enough. You may be OK with aggressive surgical treatment alone. If you do both, you are covering all the bases.” Consider the patient variables and remember the old saying, “If the odds are a million to one against complications, consider it to be a 50-50 chance.” This keeps me on my toes when I’m feeling too confident. An aggressive surgical posture against osteomyelitis will generally result in your patient coming out ahead at the end of the day. Remember, sustaining life and function supercedes the goal of preservation. Dr. Dujela (right) is an Associate of the American College of Foot and Ankle Surgeons and practices at the Centralia Medical Center in Centralia, Wash. No, Dr. Espensen says different cases of osteomyelitis warrant different solutions. He says there are many elements to consider in arriving at an individually tailored treatment course. Osteomyelitis is often a dreaded diagnosis for both the doctor and patient. The Merck Manual defines osteomyelitis as inflammation and destruction of bone caused by aerobic and anaerobic bacteria, mycobacteria and fungi.1 Classically, osteomyelitis has been addressed by both medical and surgical management. Indeed, the long accepted approach to treating osteomyelitis has involved surgical removal of the infected bone along with antibiotic therapy that is typically administered intravenously for four to six weeks. This approach to treatment has been considered the standard of care for many years. This established treatment regimen is dependent upon several factors including: location and duration of infection; pathogenic organisms with culture and sensitivity results; the patient’s medical status and allergy status; patient compliance, etc. Within the scope of podiatry, osteomyelitis can affect any bone of the foot and leg. In terms of severity, it may range from a relatively small acute case to a large scale, chronic condition. Treating the condition can be complicated as one has to consider the impact of osteomyelitis on weightbearing, ambulation and function. One also must appreciate the patient’s medical and health status. Specifically, you must consider the vascularity of the affected limb, the presence of diabetes, immune status, location of the osteomyelitis and level of involvement. The management of osteomyelitis is obviously not a simple issue. For thorough diagnosis and treatment, osteomyelitis frequently requires the involvement of the patient’s primary care physician, an infectious disease specialist and other specialists depending upon the medical status of the patient. Making matters even more intricate is the fact that surgical treatment by a podiatrist depends upon one’s training, scope of practice, hospital privileges, state and local laws, etc. Emphasizing Prudence And Careful Planning One of the many debates surrounding osteomyelitis is its diagnosis. The gold standard for diagnosing osteomyelitis is pathological inspection of bone with findings of osteonecrosis, osteolysis and the isolation of the responsible pathogen, whether it is bacterial or fungal in nature. Many papers, studies and texts exist on this topic and research continues in this field. Treating osteomyelitis requires prudence and careful planning. One can treat many cases of osteomyelitis conservatively with the appropriate antibiotics and achieve ideal and acceptable outcomes. However, severe cases often require surgical intervention to remove large sections of necrotic bone with bone grafting to repair and rebuild the affected areas. This often entails using tissue flaps and skin grafts to replace, repair and allow for surgical closure over the affected areas. As I noted above, it is common practice to treat all osteomyelitis with four to six weeks of appropriate antibiotic coverage and possible surgical intervention. This has long been the standard of care accepted by physicians and patients. Does this mean this is the most beneficial and effective course of management? This question only serves to fuel the need for research and investigation into the field. What The Current Literature Reveals Within the last decade, there has been a large movement toward evidence-based medicine and the need for large scale clinical and research data to aid in establishing guidelines, protocols and treatment plans. The optimal approach towards osteomyelitis has yet to be established by means of large-scale, prospective randomized trials. However, over the last several years, several published studies have shown that one can successfully treat osteomyelitis in diabetes patients with antibiotics and achieve long term remission.2-10 While there is no common basis for diagnosis, treatment and outcomes in these studies, cumulative study results have reported successful treatment outcomes in more than 400 patients with osteomyelitis.2-10 In the published studies that have reported success with a surgical approach, there is again no common basis except the fact that researchers have almost always combined surgery with some form of antibiotic therapy. Published results vary from complete successes to therapeutic failures. While it is understood and accepted that long courses of the appropriate antibiotic with surgical intervention (if needed) have been successful, a proven efficacy rate has not been demonstrated by means of randomized research results. Many studies are currently assessing the effectiveness of antibiotic therapy for osteomyelitis. Until more published research is available on the subject, we should apply the accepted standard of therapy for osteomyelitis appropriately. Doing so requires us to assess and treat each patient individually. Can every case of osteomyelitis be managed without surgery? Does every case of osteomyelitis require surgery? The obvious answer is every case is different. Common Factors To Consider When Forming A Treatment Plan There are several factors that commonly affect the management of osteomyelitis in the foot. With this in mind, here are several main issues to consider before deciding on a course of action. Is it acute or chronic osteomyelitis? When you’re dealing with a case of osteomyelitis that has been present for several months with poor response to antibiotic therapy, you’ll often need to proceed to surgical intervention. Determine the extent of involvement. A case of osteomyelitis that is small and only involves a part of one bone has a much higher likelihood of being treated successfully with medical management. Large-scale involvement of several bones with extensive destruction is another matter. Determine the medical status of the patient. When you’re treating a relatively healthy and uncomplicated patient, there is more latitude for treatment options. However, in a medically complicated patient with extensive disease and very poor pedal vascularity, treatment is often limited by what the patient can tolerate and survive. To further complicate the issue, renal dysfunction and immunosuppression can make osteomyelitis very challenging and difficult to treat. What is the responsible pathogen? The increase of antibiotic resistance complicates the conservative treatment of osteomyelitis. However, new classes of antibiotics, the increase in bioavailability and the increased use of antibiotic combinations may result in long-term remission in many cases of osteomyelitis. Is surgery needed, warranted or permitted? Can you perform the needed surgery? Can the patient tolerate the surgery? Will the patient consent to the surgery? Final Notes Each case of osteomyelitis is unique in that each patient has different needs, issues and demands. All things considered, each case of osteomyelitis requires comprehensive assessment and a treatment plan developed and tailored to the case at hand. Osteomyelitis is far too complicated an issue to conclude that it is primarily a surgical disease. The most appropriate treatment must include appropriate patient assessment and management planning. Obviously, there is a need for surgical involvement in the treatment of osteomyelitis. However, medical management and treatment must dictate the treatment course one takes for osteomyelitis. Dr. Espensen is the Assistant Director of the Providence Diabetic Foot Center at the Providence St. Joseph Medical Center in Burbank, Calif. He lectures frequently on the diabetic foot and wound healing technologies.
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