The Role of Complete Suprapatellar Plicae.

Shelf syndrome mainly affects younger people, often athletes. Cases of complete suprapatellar plica syndrome are rare. Arthroscopic inspection is necessary to diagnose complete suprapatellar plicae. The patients' symptoms improve after removal of the plicae. Our technique is an easy, completely arthroscopic procedure that has yielded good clinical outcomes in patients who have complete suprapatellar plicae. Although cases of complete suprapatellar plica syndrome are rare, it should be considered in patients with moderate knee pain.

Normal Values of Diffusion Tensor Magnetic Resonance Imaging Parameters in the Cervical Spinal Cord.

STUDY DESIGN: Prospective study. PURPOSE: We evaluated the usefulness of diffusion tensor imaging (DTI) in diagnosing patients with cervical myelopathy by determining the accuracy of normal DTI parameter values. OVERVIEW OF LITERATURE: DTI can visualize white matter tracts in vivo and quantify anisotropy. DTI is known to be more sensitive than conventional magnetic resonance imaging (MRI) in detecting subtle pathological changes of the spinal cord. METHODS: A total of 31 normal subjects (13 men and 18 women; age, 23-87 years; mean age, 46.0 years) were included in this study. The patients had no symptoms of myelopathy or radiculopathy. A Philips Achieva 3-Tesla MRI with SE-type Single Shot EPI was used to obtain diffusion tensor images. Apparent diffusion coefficient (ADC) and fractional anisotropy (FA) values were measured as DTI parameters on axial sections of several cervical levels. Subjects were divided into two groups: >40 years (n=16) and ≤40 years (n=15). A paired t-test was used to compare significant differences between the groups. ADC and FA values were most stable on axial sections. RESULTS: For all subjects, mean ADC and FA values were 1.06±0.09×10(-3) mm(2)/sec and 0.68±0.05, respectively. ADC was significantly higher in subjects >40 years of age than in those ≤40 years. There was no significant difference in FA values between the two groups. The mean ADC value was significantly higher in normal subjects >40 years of age than in those ≤40 years. CONCLUSIONS: It is important to consider age when evaluating cervical myelopathy by DTI.

Texture analysis on (18)F-FDG PET/CT images to differentiate malignant and benign bone and soft-tissue lesions.

OBJECTIVE: The purpose is to develop and evaluate the ability of the computer-aided diagnosis (CAD) methods that apply texture analysis and pattern classification to differentiate malignant and benign bone and soft-tissue lesions on 18F-fluorodeoxy-glucose positron emission tomography/computed tomography ((18)F-FDG PET/CT) images. METHODS: Subjects were 103 patients with 59 malignant and 44 benign bone and soft tissue lesions larger than 25 mm in diameter. Variable texture parameters of standardized uptake values (SUV) and CT Hounsfield unit values were three-dimensionally calculated in lesional volumes-of-interest segmented on PET/CT images. After selection of a subset of the most optimal texture parameters, a support vector machine classifier was used to automatically differentiate malignant and benign lesions. We developed three kinds of CAD method. Two of them utilized only texture parameters calculated on either CT or PET images, and the other one adopted the combined PET and CT texture parameters. Their abilities of differential diagnosis were compared with the SUV method with an optimal cut-off value of the maximum SUV. RESULTS: The CAD methods utilizing only optimal PET (or CT) texture parameters showed sensitivity of 83.05 % (81.35 %), specificity of 63.63 % (61.36 %), and accuracy of 74.76 % (72.82 %). Although the ability of differential diagnosis by PET or CT texture analysis alone was not significantly different from the SUV method whose sensitivity, specificity, and accuracy were 64.41, 61.36, and 63.11 % (the optimal cut-off SUVmax was 5.4 ± 0.9 in the 10-fold cross-validation test), the CAD method with the combined PET and CT optimal texture parameters (PET: entropy and coarseness, CT: entropy and correlation) exhibited significantly better performance compared with the SUV method (p = 0.0008), showing a sensitivity of 86.44 %, specificity of 77.27 %, and accuracy of 82.52 %. CONCLUSIONS: The present CAD method using texture analysis to analyze the distribution/heterogeneity of SUV and CT values for malignant and benign bone and soft-tissue lesions improved the differential diagnosis on (18)F-FDG PET/CT images.

Unusual appearance of an osteochondral lesion accompanying medial meniscus injury.

An osteochondral lesion in the knee joint is caused by a focal traumatic osteochondral defect, osteochondritis dissecans, an isolated degenerative lesion, or diffuse degenerative disease. An osteochondral lesion with a cleft-like appearance accompanying medial meniscus injury is rare without trauma. We report the case of a 13-year-old boy who complained of right knee pain and swelling, with radiographic findings of an osteochondral defect. Arthroscopic inspection showed an osteochondral lesion in the medial condyle of the femur and tibial plateau accompanying a partial medial meniscus discoid tear. Partial meniscectomy was performed, and a microfracture procedure was carried out on the osteochondral defect. The patient was asymptomatic at 2 years' follow-up. This technique is a relatively easy, completely arthroscopic procedure that spares the bone and cartilage and has yielded a good clinical outcome in a skeletally immature patient who had an osteochondral lesion with a cleft-like appearance.

Intramuscular hemangioma of the upper extremity in infants and children.

PURPOSE: Intramuscular hemangiomas (IMHs) are benign tumors comprising just 0.8% of all hemangiomas and are extremely rare in the upper limbs. These tumors can pose diagnostic as well as therapeutic challenges for orthopaedic surgeons, especially in younger children. We reviewed cases of IMH of the upper extremity in infants and children from our institute. METHODS: Six consecutive patients underwent surgical treatment for IMH in our hospital. There were 4 girls and 2 boys. Long-standing pain and swelling were common symptoms except in a 1-year-old boy. Tumors were evaluated by radiography, computed tomography, magnetic resonance imaging, and angiography. RESULTS: After a mean follow-up of 42 months, all patients except one were free of pain and without tumor recurrence or functional impairment. Minimal symptoms remained in a 6-year-old boy who underwent biopsy only. CONCLUSION: Magnetic resonance imaging is the most useful evaluation for IMH because it not only delineates the extent of tumor but also reveals characteristic structures. For young children with IMH, wide excision is the treatment of choice to prevent local recurrence, but every patient should be treated individually after evaluating the patient's age, tumor location and invasion, and cosmetic considerations. LEVEL OF EVIDENCE: Therapeutic study-level III.