|89th Annual Meeting Abstracts
Is There a Simple, Definitive, and Cost Effective Way to Diagnose Osteomyeleitis in the Pressure Ulcer Patient?
Jarom Gilstrap, MD, David L. Larson, M.D., Guillermo F. Carrera, M.D..
Medical College of Wisconsin, Milwaukee,, WI, USA.
Despite advances in the evaluation and management of pressure ulcer wounds, there is still no definitive means to make a diagnosis of osteomyelitis, short of an open biopsy. If an equally effective, less invasive, method of diagnosing osteomyelitis can be determined, a strategy for management of these patients could be applied. The literature suggests needle aspiration, CT scan and/or MRI studies, ultrasound, or bone scans as possible answers to this question_none have proven to be successful in predicting the presence or absence of osteomyelitis.
A blinded review of the preoperative radiologic studies of Stage IV pressure ulcer patients and the results of their bone biopsy, taken under sterile conditions, were matched in hopes of determining what, if any, radiologic studies are the most diagnostic for osteomyelitis.
In this IRB approved study, patients treated with surgical débridement of stage IV pressure ulcers, accompanied by an open, intraoperative, bone biopsy, after having prior radiographic imaging of the bone, were included. The studies may or may not have been done for indications of local osteomyelitis (e.g. renal stones). Patients with multiple pressure ulcers (e.g. bilateral ischial ulcers) or pressure ulcers separated by a period of time (>6 months) were analyzed as separate pressure ulcers. Stage IV pressure ulcers not treated with surgical debridement or treated, but lacking radiographic imaging or intra-operative bone biopsy, were excluded.
Radiographic imaging of the affected area included plain films, ultrasound, computed tomography (CT), magnetic resonance imaging (MRI) and/or nuclear bone scans obtained up to one year pre-operatively. The radiographic studies were interpreted by a single musculoskeletal radiologist. The radiologist was blinded to information from the medical record. Standard radiologic criteria for the diagnosis of osteomyelitis were applied.
Fifty-seven patients had open bone biopsies in conjunction with definitive repair of a pressure ulcer, 6 had no relevant radiologic studies and were not included in the study. Thirty two patients had at least one radiologic study within three months of surgery.
Only 50% of the patients who had CT scans and later culture proven osteomyelitis had the diagnosis suggested; while 88% of those who had plain films and later cultures positive for osteomyelitis had that diagnosis.
The overall sensitivity of either radiologic study was 61%.
The percentage of patients without osteomyelitis who were identified as not having the condition by imaging was 85% for the CT scan and 32% for the plain film. The overall specificity of both studies was 69%.
It would appear that preoperative radiologic studies for osteomyelitis in a pressure ulcer are far from definitive and might only be of value in defining the extent of disease for surgical planning purposes. Additionally, making a radiographic diagnosis of osteomyelitis and subsequent commitment to long term intravenous antibiotics may not the best use of our limited healthcare resources. Regardless, if a radiologic study were used to make that diagnosis in a stage IV pressure ulcer, it would appear that a study as simple as a plain film would suffice.