Radiographic signs of hook of hamate fracture: evaluation of diagnostic utility.

OBJECTIVE: Hook of hamate fracture, the most common swing-related wrist fracture, is commonly seen in high-level athletes. The fracture is rarely diagnosed on routine wrist radiographs, thus generally requiring CT or MR for diagnosis. Surgical excision has a high success rate, however diagnostic delay contributes to a high complication rate. Radiographic signs of hook of hamate fracture have been published, but uncertainty of the diagnostic accuracy limits application. The purpose of this study is to determine accuracy and interobserver reliability of radiographic signs of hook of hamate. MATERIALS AND METHODS: This retrospective case-control study evaluated wrist radiographs of 50 patients, including 24 positive and 26 negative, for hook of hamate fracture, each proven by CT or MR. Five reviewers performed blinded, randomized evaluation of radiographs documenting whether the hook of hamate was normal or fractured, and if fractured, the radiographic signs present (ring sign, ghostly shadow, and diffuse sclerosis) and views that contributed to diagnosis. RESULTS: Radiographic signs demonstrated high sensitivity (85%; 95% CI: 77-91), specificity (92%; 95% CI: 86-96), and accuracy (89%; 95% CI: 84-92) with substantial interobserver reliability (k = 0.652). The ring sign was the most sensitive radiographic sign. Diagnosis was most often supported by the oblique view (38%) and rarely the lateral view (15%). CONCLUSIONS: Radiographic signs of hook of hamate fracture on routine radiographs can accurately and reliably diagnose hook of hamate fractures. Evaluation for discontinuity of the cortical ring will optimize sensitivity, allowing for timely diagnosis and treatment, and a reduction of complications.

Methicillin-resistant Staphylococcal aureus patellar tendon abscess and septic prepatellar bursitis in an injection drug user.

We report a case of intratendinous patellar abscess and prepatellar septic bursitis following direct inoculation in a 26-year-old male injection drug user. The patient presented with 2 days of progressive knee pain, swelling, and erythema. Computed tomography demonstrated an enlarged patellar tendon with central low attenuation. Ultrasonography revealed a complex intratendinous fluid collection concerning for abscess. Aspiration of this fluid collection yielded grossly purulent fluid which grew methicillin-resistant staphylococcal aureus. The patient subsequently underwent operative debridement which revealed an intratendinous patellar abscess with extension to involve the prepatellar bursa. This case report demonstrates typical, though nonspecific, radiographic findings of abscess in an atypical location and highlights the importance of clinical history in diagnosing musculoskeletal disorders, particularly in the absence of traditional types of traumatic injury.

Intravascular large B-cell lymphoma presenting with diffusely increased pulmonary fluorodeoxyglucose uptake without corresponding CT abnormality.

A 60-year-old male presented with complaints of dyspnea, intermittent fever, and 40 pounds of weight loss over the previous 9 months and was admitted for acute hypoxemic respiratory failure. Labs demonstrated elevated inflammatory markers, mild anemia, and thrombocytopenia. Fluorodeoxyglucose-positron emission tomography scan demonstrated diffusely increased pulmonary fluorodeoxyglucose uptake without corresponding abnormality on CT images. Excisional lung biopsy demonstrated intravascular large B-cell lymphoma (IV-LBCL). Presentation, imaging findings, and diagnosis of IV-LBCL will be discussed, as well as differential considerations for pulmonary involvement by IV-LBCL.