Osteoid osteoma of the spine treated with percutaneous computed tomography-guided thermocoagulation.

STUDY DESIGN: Two cases are reported in which an osteoid osteoma of the lumbar spine was treated with CT-guided thermocoagulation. OBJECTIVES: To review an alternative and minimally invasive treatment for spinal osteoid osteomas. SUMMARY OF BACKGROUND DATA: Surgical resection of a spinal osteoid osteoma can, depending on the location, be a formidable undertaking. Bone scintigraphy can be helpful in intraoperative identification. More recently, resection through a computed tomography-guided drill hole was found to minimize exposure. Using a thermocoagulation probe, as has been used in osteoid osteoma of the extremities, may be technically easier and cause less morbidity. METHOD: With the patient under general anesthesia, a bone biopsy cannula was introduced into the center of the osteoid osteoma. Material was subjected to histologic examination. A thermocoagulation probe was then inserted and heated to 90 C for 4 minutes. The two patients were kept overnight for observation. RESULTS: Both patients had complete pain relief and no evidence of recurrence after 2 years' follow-up. There were no complications. Scoliosis resolved in one patient and persisted in the other. CONCLUSION: Percutaneous computed tomography-guided thermocoagulation is a minimally invasive and technically straightforward method to achieve ablation of a spinal osteoid osteoma. No complications were encountered in these two patients. Future research should focus on the safety of thermocoagulation, especially cephalad to the level of the conus medullaris.

US of the ankle: technique, anatomy, and diagnosis of pathologic conditions.

For specific indications, ultrasound (US) is an efficient and inexpensive alternative to magnetic resonance (MR) imaging for evaluation of the ankle. In addition to the tendons and tendon sheaths, other ankle structures demonstrated with US include the anterior joint space, retrocalcaneal bursa, ligaments, and plantar fascia. Ankle US allows detection of tenosynovitis and tendinitis, as well as partial and complete tendon tears. Joint effusions, intraarticular bodies, ganglion cysts, ligamentous tears, and plantar fasciitis can also be diagnosed. As pressure for cost containment continues, demand for US of the ankle may increase given its lower cost compared with that of MR imaging. In most cases, a focused ankle US examination can be performed more rapidly and efficiently than MR imaging. Familiarity with the technique of ankle US, normal US anatomy, and the US appearances of pathologic conditions will establish the role of US as an effective method of imaging the ankle.

US depiction of partial-thickness tear of the rotator cuff.

PURPOSE: To test previously defined ultrasound (US) criteria for identification of partial-thickness tears of the rotator cuff. MATERIALS AND METHODS: Before shoulder arthroscopy, 52 patients with shoulder pain for more than 3 months were examined with a 7.5-MHz commercially available linear-array transducer and a standardized study protocol. The criteria used to detect partial-thickness tears were (a) a mixed hyper- and hypoechoic focus in the crucial zone of the supraspinatus tendon and (b) a hypoechoic lesion visualized in two orthogonal imaging planes with either articular or bursal extension. RESULTS: The US findings were reported as partial-thickness tears in 17 shoulders, of which three were false-positive findings. There was one false-negative finding. The sensitivity of US in depiction of partial-thickness tears was 93%, and specificity was 94%. The positive predictive value was 82%, and the negative predictive value was 98%. CONCLUSION: US can depict most partial-thickness tears with use of the criteria described.