Characterization of Pulmonary Emboli in Total Joint Arthroplasty Patients Compared to General Medical Patients.

Pulmonary emboli (PEs) occur in medical and postoperative total joint arthroplasty (TJA) patients. These are different patient populations, yet both undergo identical diagnosis and treatment regardless of PEs size and quantity. To date, there has been no analysis of the location, size, and quantity of emboli that occur postoperatively in TJA compared with general medical patients. We hypothesized TJA patients would have different size and distribution of PEs per event compared with medical patients. A retrospective chart review was conducted of patients who underwent total hip or knee arthroplasty in comparison to general medical patients at our institution from 2006 to 2011 with a PE diagnosis. Medical co-morbidities, sex, age, procedure, postoperative day, size, and location of PE using spiral computed tomography were recorded using a novel mapping scheme. Embolus size was defined based on blockage level in the pulmonary arterial tree. Of the 4,178 TJA patients reviewed, 51 were diagnosed with a PE. A total of 67% of TJA patients were women, yet women represented 90% (n = 46) of TJA PE patients (p < 0.0001). Medical patients had an equal distribution of men and women with PEs. Orthopaedic patients averaged more (4.0 vs. 2.2, p < 0.0001) and smaller PEs compared with medical patients (p < 0.0001). In conclusion, women undergoing TJA had significantly higher risk of developing PE compared with male arthroplasty or medical patients. Differences were observed in size and distribution of PEs between medical and TJA patients, which suggest a different nature of embolic phenomenon.

Neurolymphomatosis of the lumbosacral plexus and its branches: case series and literature review.

BACKGROUND: Neurolymphomatosis (NL) is a direct process of invasion of peripheral nerves by lymphoma. It occurs in roughly 5% of patients with lymphoma and represents a particularly difficult diagnostic dilemma when it is the presenting focal manifestation of occult lymphoma. CASE PRESENTATION: We present 3 examples of invasion of the lumbosacral plexus and its branches. These cases demonstrate a protean clinical picture with regards to the time relationship to the clinical course of lymphoma and the neuroanatomical extent of lumbosacral plexus invasion. We demonstrate the complementary role of different imaging modalities. A review of the literature summarizes 23 reports where lumbosacral plexus invasion was the index manifestation, at the time of first diagnosis or recurrence of lymphoma. This series confirms the strong preponderance of B-cell type (92%). There is a marked predilection for involvement of the sciatic nerve (74%), either focally or in a longitudinally extensive fashion, from the ischium to the popliteal fossa. There can also be restricted and discrete involvement of tibial and fibular branches. In recent years, ultrasound and CT have been given a more limited role, as screening tools or as a guide for biopsy. MRI neurography and PET-CT have become leading diagnostic modalities for diagnosis, staging and assessment of treatment response. CONCLUSION: The diagnosis of NL may be challenging, and it was once only reached at autopsy. Improved diagnostic imaging of focal or even asymptomatic disease offers new hope for earlier diagnosis and successful targeted therapy.

Osteoblastic Metastases Mimickers on Contrast Enhanced CT.

Secondary osseous involvement in lymphoma is more common compared to primary bone lymphoma. The finding of osseous lesion can be incidentally discovered during the course of the disease. However, osseous metastases are infrequently silent. Detection of osseous metastases is crucial for accurate staging and optimal treatment planning of lymphoma. The aim of imaging is to identify the presence and extent of osseous disease and to assess for possible complications such as pathological fracture of the load-bearing bones and cord compression if the lesion is spinal. We are presenting two patients with treated lymphoma who were in complete remission. On routine follow-up contrast enhanced CT, there were new osteoblastic lesions in the spine worrisome for metastases. Additional studies were performed for further evaluation of both of them which did not demonstrate any corresponding suspicious osseous lesion. The patients have a prior history of chronic venous occlusive thrombosis that resulted in collaterals formation. Contrast enhancement of the vertebral body marrow secondary to collaterals formation and venous flow through the vertebral venous plexus can mimic the appearance of spinal osteoblastic metastases.