Isolated adult Tillaux fracture: a report of two cases.

A fracture of the lateral margin of the distal tibia has commonly been called a Tillaux fracture, which is an avulsion-type fracture that can result from the pull of the anterior inferior tibiofibular ligament. The common mechanism of injury described and observed has been one of external rotation of the foot relative to the tibia. Historically, this fracture pattern has been noted in the pediatric and adolescent populations and classified as a Salter-Harris III fracture through the epiphysis. It has typically occurred in children aged 12 to 14 years and is not commonly seen in adults. We discuss 2 cases of isolated Tillaux fractures in skeletally mature adults, aged 47 and 37 years, a population in which this fracture pattern to our knowledge and after review of the published data has not been described. It is important to recognize these distinct injuries and appropriately treat the pathologic features to prevent further instability and arthritis.

Magnetic resonance imaging of acute patellar dislocation in children: patterns of injury and risk factors for recurrence.

BACKGROUND: Acute patellar dislocation is a common traumatic condition of the knee seen in the active adolescent. The patterns of injury to the ligamentous and chondral surfaces following dislocation have not been well defined in the pediatric population. The purpose of this study was to characterize the patterns of medial patellofemoral ligament (MPFL), vastus medialis obliqus (VMO), and osteochondral injury on magnetic resonance imaging (MRI) following first-time acute lateral patellar dislocation in pediatric patients. METHODS: Following approval by the Institutional Review Board, a radiology query was performed to identify all patients between the ages of 11 and 18 years who underwent MRI following an acute first-time patellar dislocation over a 10-year period. The presence and location of injury to the MPFL, VMO, and chondral surfaces were evaluated on MRI images. A retrospective review of the patient's chart was conducted to confirm that clinical history was consistent with an acute patellar dislocation. Demographic data, including age at the time of injury, sex, knee affected, mechanism of injury, and recurrence of dislocation, were retrieved from the chart. The data were analyzed as a single cohort. RESULTS: One hundred and eleven patients, including 56 males and 46 females with a mean age of 14.9 years (range, 11 to 18 y), were included. MRI demonstrated MPFL injury in 87 patients (78.4%). MPFL injury was present at an isolated patellar insertion in 34 patients (31%) and an isolated femoral insertion in 16 patients (14%). MPFL injury at more than one location was present in 37 patients (33%). VMO edema was present in 62 patients (56%), consistent with sprain or tear. Osteochondral fracture was identified in 38 knees (34%), with 25 from the medial patellar facet, 5 from the lateral femoral condyle, and 8 from both locations. CONCLUSIONS: Acute patellar dislocations remain a common injury in pediatric patients. The pattern of injury to the MPFL and VMO on MRI has not been described in a pediatric population. The triad of injury to the MPFL, VMO, and chondral surfaces should be recognized and understood, particularly when surgical reconstruction is necessary. LEVEL OF EVIDENCE: Level III.

Acoustic access to the prostate for extracorporeal ultrasound ablation.

This study aimed to measure acoustic access to the prostate for extracorporeal ultrasound ablation. Both transabdominal and transperineal approaches were considered. The objective was to measure the size and shape of the aperture available for unobstructed targeting of the prostate. CT images of 17 randomly selected men > 56 years of age were used to create 3D reconstructions of the lower abdomen and pelvis. Rays were traced from target locations in the prostate toward the perineum and the abdomen. The maximum CT density encountered along each path was recorded; those paths that traversed structures with CT density exceeding a soft tissue threshold were considered to be blocked by bone. Unblocked rays comprised the accessible aperture. The aperture through the perineum was found to be a triangular-shaped region bounded by the lower bones of the pelvis varying significantly in size between subjects. The free aperture through the abdomen was wedge shaped limited by the pubis and also with great subject-to-subject variability. Average unblocked fractions of an f/1 transducer to target base, middle, and apex of the prostate along the urethra from the perineum were 77.0%, 94.4%, and 99.6%, respectively. Averages targeting from the abdomen were 86.1%, 52.3%, and 11.0%. Acoustic access to the prostate for therapy through the perineum was judged to be feasible. Access from the abdomen was judged to be sufficient for the base of the prostate, but likely inadequate for the middle and apex.

Musculoskeletal sonography: important imaging pitfalls.

OBJECTIVE: The purpose of this article is to describe the pitfalls that may be encountered when performing musculoskeletal sonography. CONCLUSION: Sonography of the musculoskeletal system is a useful diagnostic technique, but awareness and understanding of the pitfalls will minimize errors in diagnosis.

Radiographic evaluation of arthritis: degenerative joint disease and variations.

In the presence of joint space narrowing, it is important to differentiate inflammatory from degenerative conditions. The presence of osteophytes, bone sclerosis, and subchondral cysts and the absence of inflammatory features such as erosions suggest osteoarthritis. Typical osteoarthritis involves specific joints at a particular patient age. When osteoarthritis involves an atypical joint, occurs at an early age, or has an unusual radiographic appearance, then other causes for cartilage destruction should be considered, such as trauma, crystal deposition, neuropathic joint, and hemophilia. There are several types of arthritis, such as juvenile chronic arthritis and gouty arthritis, that may have a variable appearance compared with that of other common inflammatory arthritides.

CT-guided biopsy of bone: a radiologist's perspective.

OBJECTIVE: We present an overview of approaches for bone biopsy used to minimize potential tumor seeding of adjacent soft-tissue structures and compartments. We discuss a variety of approaches related to specific anatomic parts and review pertinent anatomy. CONCLUSION: We provide important guidelines and key examples that will help readers perform percutaneous needle bone biopsy safely.

Developmental Venous Anomaly Complicated by Cerebral Venous Infarction.

Developmental venous anomaly is a vascular malformation thought to be a benign embryologic variant. We describe a patient who presented with focal neurological deficits and parathesia due to an infarct associated with a developmental venous anomaly with a thrombosed draining vein.