Are TomoFix Locking Plates Really Anatomical for Indian Population?

Purpose: The use of a TomoFix plate can be a challenge in Asian population who inherently have smaller tibial bones. This study aims to find out the normal proximal tibial morphometric measurements in Indian population and to compare the Medial Anterior Radius of Curvature (MAROC) of proximal tibia with the Proximal Part Radius of Curvature (PPROC) of the available TomoFix plates, to estimate conformity of the fit between them. Methods: Retrospective Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) based proximal tibial measurements were performed on 824 knees, 664 females and 160 males (604 patients). The mean MAROC, mean MAROC in males and mean MAROC in females were compared to the PPROC of TomoFix plates. Results: The radiological measurements revealed a mean AP length of 45.22 ± 3.79 mm, mean ML width of 69.04 ± 5.01 mm and mean MAROC of 21.88 ± 2.11 mm. The mean MAROC in males was 24.07 ± 2.1 mm, whereas in females it was 21.35 ± 1.75 mm. The mean MAROC, mean MAROC in males and mean MAROC in females when compared to the PPROC of Standard TomoFix plate (38 mm), Small TomoFix and Anatomical TomoFix plates (30 mm) showed a significant difference (p < 0.01), indicating that the radius of curvature of the plate does not match the radius of curvature of the anteromedial tibial plateau. Conclusion: The TomoFix plates, including Small (Asian Version) and Anatomical plates, are relatively large for the Indian population. Our study may help the implant to designers develop a plate that will better suit the Indian population, improving results and reducing hardware-related complications of MOWHTO.

Physical activity increases synovial fluid in ankle tendon sheaths: an adjustment of MR Criteria is needed.

OBJECTIVES: To compare the amount of fluid in synovial sheaths of the ankle before and after running. Our hypothesis was that this amount would increase and that the threshold for what is normally acceptable should be adjusted after physical activity. METHODS: Twenty-one healthy volunteers (n = 42 ankles) ran for 40 min on a treadmill. They underwent 3 T MRI before and immediately after running using a dedicated ankle coil. The images were stored and subsequently measured in a standardized way and independently read by two readers for fluid in the tendon sheaths in the retro and inframalleolar area. Statistics were performed for each tendon (Wilcoxon signed rank test), and also for the pooled data. Intraclass correlation coefficients were calculated. RESULTS: For reader 1, for all tendons the values after running increased without reaching statistical significance. For reader 2 this was not the case for all tendons but for most. When all the data were pooled (n = 800 measurements), the statistical difference before and after running was significant (p < 0.001). CONCLUSION: Data pre and post-running show a trend of increasing synovial fluid, however, not significant for each individual tendon. The pooled data for all tendons, (n = 800) show a statistically significant increase after running (p < 0.001). The clinical implication is that the threshold for normally acceptable fluid should be adjusted if the patient undergoes an MR study after recent physical activity.

Unusual CT Appearance of Bony Metastases from Malignant Peripheral Nerve Sheath Tumor.

We present a case of bone metastases from a malignant peripheral nerve sheath tumor (MPNST). While multiple bone lesions typically are suggestive of metastatic disease, especially in combination with a primary tumor and positive PET, the appearance of lesions in this patient was quite atypical. We are not aware of any case of metastatic disease with such atypical doughnut appearance as in our case.

What can the Radiologist do to Help the Surgeon Manage Shoulder Instability?

Imaging of the shoulder forms an important adjunct in clinical decision making in patients with shoulder instability. The typical lesions related with classic anterior and anteroinferior shoulder dislocation are an anteroinferior labral avulsion with or without bony fragment of bone loss - a (bony) Bankart lesion - and a posterolateral humeral head impaction fracture - the Hill-Sachs lesions. These are relatively straightforward to identify on imaging, although normal variants of the inferior labrum and variants of labral damage may cause confusion. Other capsuloligamentous lesions, often associated with less typical types of instability, are much more difficult to identify correctly on imaging, as they occur in the anterosuperior part of the glenohumeral joint with its many normal variants or because they result in more subtle, and therefore easily overlooked, changes in morphology or signal intensity. This paper aims at describing the appearance of the normal and pathologic glenohumeral joint related to shoulder instability. Ample reference will be given as to why identification of abnormalities, whether normal or pathologic, is important to the surgeon facing a treatment decision.