Synovial hemangioma of the knee joint in a 12-year-old boy: a case report.

INTRODUCTION: Synovial hemangioma is a rare condition and is frequently misdiagnosed, leading to a diagnostic delay of many years. CASE PRESENTATION: We present a case of an atypical synovial hemangioma in a 12-year-old Caucasian boy with a diagnostic delay of 3 years. CONCLUSION: It is important to know that synovial hemangioma mostly affects the knee joint, showing recurrent bloody effusions without a history of trauma. If there are no intermittent effusions, the diagnosis will be even more difficult. In cases of nonspecific symptoms and longstanding knee pain the diagnosis of a synovial hemangioma should also be considered in order to avoid diagnostic delay. Magnetic resonance imaging is the main diagnostic tool to evaluate patients with synovial hemangioma, showing characteristic lace-like or linear patterns.Angiography can identify feeder vessels and offers the possibility of embolisation in the same setting. Surgical excision, either done per arthroscopy or per arthrotomy, is recommended as soon as possible to avoid the risk of damage to the cartilage.

MRI-demonstrated outcome of subchondral stress fractures of the knee after treatment with iloprost or tramadol: observations in 14 patients.

OBJECTIVE: To investigate the outcome of subchondral stress fractures (SSF) of the knee after treatment with the prostacyclin analogue Iloprost or the opioid analgesic Tramadol. DESIGN: Case series/retrospective review. SETTING: Tertiary care center. PATIENTS: Fourteen patients with at least a single subchondral stress fracture of the knee, surrounded by bone marrow edema, visible on T1-weighted and short tau inversion recovery magnetic resonance images. INTERVENTIONS: Nine patients had been treated with oral Iloprost (group 1; 11 SSF) and 5 patients with Tramadol (group 2; 5 SSF) for 4 weeks in the course of a double-blind, randomized clinical trial. MR images were obtained at baseline (1 day before the start of treatment), after 3 months, and after 1 year. MAIN OUTCOME VARIABLES: SSF volumes and their rates of change between baseline and follow-up examinations, as determined on T1-weighted images by computer-assisted quantification. RESULTS: After three months, the SSF volumes had decreased by a median of 42.2% in group 1 and increased by a median of 2.2% in group 2 (P = 0.008). After 1 year, the median decrease in SSF volumes was 100.0% in group 1 and 65.7% in group 2 (P = 0.017). CONCLUSION: This small case series suggests that healing of SSF is more pronounced after Iloprost treatment.

Painful bone marrow edema of the knee: differential diagnosis and therapeutic concepts.

Bone marrow edema (BME) is a common finding when patients with knee pain are evaluated by MRI. The typical MRI signal patterns for BME are nonspecific, however. This article categorizes painful BME of the knee joint into three distinct etiologic groups and briefly describes therapeutic approaches for each of the 12 different types of BME.