Unsuspected lower extremity deep venous thrombosis simulating musculoskeletal pathology.

OBJECTIVE: The purpose of this study was to highlight the critical role that MRI may play in diagnosing unsuspected lower extremity deep venous thrombosis and to stress the importance of scrutinizing MRI studies of the lower extremity showing apparently non-specific muscle edema for any evidence of intramuscular venous thrombosis. DESIGN AND PATIENTS: The imaging studies of four patients in whom deep venous thrombosis was unsuspected on clinical grounds, and first diagnosed on the basis of MRI findings, were reviewed by two musculoskeletal radiologists in consensus. In all four patients the initial clinical suspicion was within the scope of musculoskeletal injuries (gastrocnemius strain, n=3; ruptured Baker cyst, n=1), explaining the choice of MRI over ultrasound as the first diagnostic modality. RESULTS: All patients showed marked reactive edema in the surrounding soft tissues or muscles. Three patients showed MR evidence of branching rim-enhancing structures within intramuscular plexuses characteristic of venous thrombosis (gastrocnemius, n=1; sural, n=2); one patient showed a distended popliteal vein. Ultrasound was able to duplicate the MRI findings in three patients: one patient showed above-the-knee extension on ultrasound; neither of the two patients with intramuscular thrombosis demonstrated on ultrasound showed extension to the deep venous trunks. CONCLUSION: Intramuscular venous thrombosis can present as marked edema-like muscle changes on MRI, simulating primary musculoskeletal conditions. In the absence of clinical suspicion for deep venous thrombosis, only the identification of rim-enhancing branching intramuscular tubular structures will allow the correct diagnosis to be made.

Flexor carpi radialis tendinopathy: spectrum of imaging findings and association with triscaphe arthritis.

OBJECTIVE: To present the spectrum of pathology affecting the flexor carpi radialis (FCR), and its anatomical, functional and clinical relationship with conditions affecting the triscaphe or scapho-trapezium-trapezoid (STT) compartment, and particularly osteoarthritis. DESIGN: The study comprised two men and four women aged between 23 and 79 years (mean age, 49 years). Two musculoskeletal radiologists in consensus evaluated MRI findings. RESULTS: Five of the patients showed evidence of triscaphe osteoarthritis. One of the patients showed synovitis and reactive marrow edema at the triscaphe joint without more specific findings of osteoarthritis. Five patients showed evidence of FCR tenosynovitis. Partial-thickness tears were noted in three patients. Two patients showed complete discontinuity of the FCR; one of them had undergone prior tendon harvesting for interposition arthroplasty after trapezectomy. One patient showed a ganglion cyst in connection to the FCR tendon sheath. CONCLUSION: The FCR tendon courses over the volar surfaces of the scaphoid and trapezium in a separate fibro-osseous tunnel. This anatomical and functional relationship explains the coexistence of FCR tendinopathy and STT arthritis demonstrated by MR imaging.