Core needle biopsies of musculoskeletal tumors: potential pitfalls.

Core needle biopsy is a powerful tool used to diagnose and develop a treatment strategy for musculoskeletal tumors. With accuracy rates reported between 69% and 99%, it is evident that errors in diagnosis occur, and they can lead to devastating consequences. We reviewed pathology reports of preoperative core needle biopsies in an attempt to determine factors associated with false negative diagnoses for the purpose of improving surgical planning. We retrospectively reviewed all office-based core needle biopsies accomplished in our practice over a 6-year period. One hundred nineteen biopsies were identified, of which 82 fulfilled criteria to be included in the study population. The pathologist's report of each biopsy was reviewed and categorized based on the findings into 1 of 2 diagnostic groups: neoplastic or nonneoplastic. The results of the biopsies were then compared to the pathology results of the final surgical resection, and the rates and nature of false negative biopsy results (unrecognized malignant pathology) were compared for each group. Seventy-one biopsies were categorized as neoplastic based on the pathology report. No false negative results were found in this group when compared to the final surgical resection pathology. Eleven biopsies were categorized as nonneoplastic, of which 6 were found to be false negatives when compared to the final surgical pathologic diagnosis. The rate of false negative results significantly increased in biopsies whose reports were categorized as nonneoplastic compared to biopsies categorized as neoplastic (P<.0001). We found core needle biopsies of musculoskeletal lesions to be safe and effective in diagnosing pathologic processes. In cases in which analysis of the biopsy specimen did not identify a specific neoplastic process, we found a high incidence of undiagnosed malignancy upon definitive surgical resection. Pathology reports of core needle biopsies that specify only normal, inflammatory, or other nonspecific tissue descriptions should alert the clinician to the increased possibility of a false negative result, and require further tissue analysis.

Preoperative lateral popliteal nerve block for intraoperative and postoperative pain control in elective foot and ankle surgery: a prospective analysis.

BACKGROUND: Limiting postoperative pain and minimizing systemic narcotic complications are important considerations in foot and ankle surgery to maximize patient comfort and promote early discharge from the hospital. Nerve blocks are valuable additions to perioperative care. A variety of nerve blocks have been advocated, but few reports have evaluated a preoperative supine approach for popliteal block in foot and ankle surgery. METHODS: We prospectively evaluated the effectiveness of a preoperative popliteal block in 25 consecutive patients undergoing a variety of foot and ankle procedures, as well as the length of block coverage, patient satisfaction, and any complications. Patients were monitored clinically and by a questionnaire at various time increments: preoperatively, in the post-anesthesia care unit (PACU), postoperative day one, and postoperative week one. RESULTS: Postoperatively, 15 of 25 patients had a complete block (motor and sensory), five of 25 patients demonstrated motor function, but denied sensation or pain, and the remaining five of 25 had sensation to light touch but no motor function or pain. None of the patients reported pain postoperatively in the PACU within an hour after surgery. The average time the block lasted was 14 hours. Overall satisfaction with the block on postoperative day one and week one was 4.8 out of 5. There were no intraneural injections, neurologic sequelae, or complications. CONCLUSIONS: We suggest that a preoperative nerve block for a sedated patient in the operating room saves time, avoids patient discomfort, augments general anesthesia, provides good postoperative pain control, and has high patient satisfaction with no significant complications.

Imaging modalities of the diabetic foot.

Charcot osteoarthropathy is a devastating process that occurs in the diabetic foot. It must be distinguished from other conditions, such as osteomyelitis, with efficiency and accuracy. The prognosis and treatment depends on it. Charcot progresses along four radiographically identifiable stages; therefore, plain films should be the first step in the evaluation. When osteomyelitis is suspected, a three-phase bone scan may allow clear enough anatomic detail to diagnosis bony involvement compared with soft tissue in the forefoot. In the midfoot, a three-phase bone scan alone is not specific enough to distinguish between Charcot and osteomyelitis. Enhancing the bone scans by adding an additional phase (four-phase) or tracer (gallium) does not appear to improve specificity significantly. Computerized bone flow studies may be more helpful in making the distinction, particularly in acute presentation. A CT scan is not indicated because the MR image will better define the anatomic extent of the process for preoperative planning. The combined WBC scans and sulfur colloid marrow scans show improved specificity and can distinguish between Charcot and osteomyelitis. Combined leukocyte scan with bone marrow imaging is superior to leukocyte and bone scan alone or in combination for detecting infection in the neuropathic foot. The combined leukocyte scan and bone marrow imaging is the current gold standard for evaluating the presence of diabetic foot infection versus osteoarthropathy, and MR imagine is the anatomic gold standard that may be used to define the extent of the process.