From the Guidelines
The initial test for hemarthrosis (blood in the joint) or hematomacrosis (blood in the joint space) is an ultrasound (US) of the affected joint, as it is highly accurate in detecting joint effusions and can guide joint aspiration if necessary. According to the study by Wang et al 1, the presence of a joint effusion at US in the setting of acute knee trauma showed a 91% positive predictive value for internal derangement. Additionally, US is excellent in detecting knee joint effusions and can detect a lipohemarthrosis, which is typically associated with intra-articular fractures, with a sensitivity of 94% and specificity of 94% 1.
Some key points to consider when using US for hemarthrosis or hematomacrosis diagnosis include:
- US is highly accurate in detecting joint effusions and guiding joint aspiration
- US can detect lipohemarthrosis, which is associated with intra-articular fractures
- US has a limited role in detecting occult knee fractures, but can detect joint effusions and guide further imaging or treatment
- US is particularly useful in the acute setting, where it can help guide diagnosis and treatment of joint injuries
It's worth noting that while other imaging modalities, such as radiography, CT, or MRI, may be used in certain cases, US is generally the initial test of choice for hemarthrosis or hematomacrosis due to its high accuracy, ease of use, and lack of ionizing radiation. However, the choice of imaging modality ultimately depends on the specific clinical scenario and the availability of imaging resources.
From the Research
Initial Test for Hematomacrosis
- The initial test for hematomacrosis can involve various imaging techniques, including ultrasound and MRI, to detect and evaluate the extent of bleeding.
- According to 2, contrast-enhanced ultrasound (CEUS) can be used to detect active hemorrhage in patients with soft-tissue hematomas, with a sensitivity and specificity of 75% and 100%, respectively.
- However, the study also notes that CEUS may have limitations, such as large hematoma size, unfavorable anatomic location, and body habitus, which can affect its accuracy.
- Another study 3 found that ultrasound-guided aspiration of musculoskeletal hematomas is a safe and effective procedure, and the sonographic appearance of a hematoma is unrelated to its age.
Diagnostic Considerations
- It is essential to consider the possibility of underlying malignancies, such as soft tissue sarcomas, when evaluating patients with hematomas, as noted in 4.
- The study highlights the importance of follow-up and biopsy in patients with questionable lesions, as diagnostic delay or inappropriate treatment may result if patients do not receive appropriate care.
- MRI perfusion (MRP) can also play a role in detecting neoplastic hematomas, with a combination of peripheral linear enhancement and increased cerebral blood volume (CBV) and cerebral blood flow (CBF) showing 100% sensitivity, specificity, PPV, and NPV, as reported in 5.
Additional Tests
- Serum ferritin levels can be used as a diagnostic test to identify patients with hereditary hemochromatosis, a genetic disorder that can cause iron overload and hematomas, as noted in 6.
- However, it is essential to exclude secondary causes of liver disease and consider other diagnoses, such as nonalcoholic fatty liver disease and alcoholic liver disease, which can also cause elevated serum ferritin levels.