Fibrocartilaginous dysplasia (FCD) has occasionally led to a misdiagnosis and wrong decision which can significantly alter the outcome of the patients. A 9-yr-old boy presented with pain on his left distal thigh for 6 months without any trauma history. Initial radiographs showed moth eaten both osteolytic and osteosclerotic lesions and biopsy findings showed that the lesion revealed many irregular shaped and sclerotic mature and immature bony trabeculae. Initial diagnostic suggestions were varied from the conventional osteosarcoma to low grade central osteosarcoma or benign intramedullary bone forming lesion, but close observation was done. This study demonstrated a case of unusual fibrocartilaginous intramedullary bone forming tumor mimicking osteosarcoma, so that possible misdiagnosis might be made and unnecessary extensive surgical treatment could be performed. In conclusion, the role of orthopaedic oncologist as a decision maker is very important when the diagnosis is uncertain.
Bone and Bones/*radiography ; Child ; Diagnosis, Differential ; Femur/radiography ; Fibrocartilage/*radiography ; Humans ; Magnetic Resonance Imaging ; Male ; Osteosarcoma/diagnosis/radiography

PURPOSE: There remains uncertain whether to fix or not an ulnar styloid fracture acommpanied by distal radius fracture. Fixation might be required in cases of the fracture involving a fovea of ulnar head, an attachment site of deep triangular fibrocartilage, which is thought to be important to distal radioulnar joint stability. We analyzed a fovea involvement of an accompanied ulnar styloid fracture in patients with distal radius fracture by simple radiograph and three-dimensional computed tomography (3D CT). METHODS: We retrospectively reviewed 168 patients who underwent surgery with volar locking plate for distal radius fracture in our hospital from January 2005 to March 2015 and evaluated a fovea involvement of ulnar head by simple radiographs and 3D CT respectively, and compared. RESULTS: On simple X-ray, 64 cases (38%) were ulnar styloid fovea fractures; however, 21 cases of these revealed non-fovea fractures by 3D CT. And 7 out of 104 cases determined as non-fovea fracture by simple radiographs were diagnosed as fovea fractures by 3D CT. Sensitivity, specificity and accuracy of evaluation by simple radiograph were 86%, 82% and 83% respectively, when compared with those of 3D CT based evaluation. CONCLUSION: Accuracy of evaluating an accompanied ulnar styloid fovea fracture in patients with distal radius fracture by simple radiograph, when compared with 3D CT, was 83%; therefore, we recommend using the 3D CT based evaluation instead of simple radiograph based one for determination of fovea involvement of ulnar head.
Head ; Humans ; Joints ; Radiography* ; Radius Fractures ; Retrospective Studies ; Sensitivity and Specificity ; Triangular Fibrocartilage

OBJECTIVETo investigate three-dimensional kinematics of the superficial and deep portion of triangular fibrocartilage complex (TFCC) in different parts of the forearm rotation.

METHODSSix wrists of 6 volunteers were used to obtain CT scans at different positions of the wrist. The wrists were scanned from 90 degrees of pronation to 90 degrees of supination at an interval of 30 degrees. The 3-dimensional radius and ulna were reconstructed with customized software and changes in length of the superficial and deep portion of TFCC during forearm rotation.

RESULTSIn forearm pronation, the superficial dorsal portion and the deep palmar portion of the TFCC were tight. While the superficial palmar portion and the deep dorsal potion of the TFCC were lax. In supination, the changes in length of all these fibers were reverse.

CONCLUSIONSIn forearm rotation one portion fibers of dorsal TFCC and one portion fibers of palmar TFCC are tight, and this mechanism controls stability during DRUJ rotation.

Adult ; Biomechanical Phenomena ; Female ; Forearm ; physiology ; Humans ; Imaging, Three-Dimensional ; Male ; Pronation ; Radiography ; Radius ; diagnostic imaging ; Supination ; Triangular Fibrocartilage ; diagnostic imaging ; Ulna ; diagnostic imaging ; Wrist Joint ; diagnostic imaging ; Young Adult