Introduction to MSK Radiology

MSK Radiology J. Wilson, E. Parker, I Al-Bakir, T Waterfield Introduction to MSK Radiology Systematic Approach to Interpreting Radiographs (ET1) Welcome to the introduction of the Musculo-Skeletal Radiology student based teaching. The purpose of our programme is to provide students undertaking the ED/Orthopaedics rotation with the opportunity to develop and practise the skills required to perform effectively in the OSCE in week 7 and hence, perform effectively as a junior doctor in the years to come. We shall be providing an introduction pack at the start of the course and a small group OSCE preparation session in week 7. This will be supplemented by more detailed information on MSK presentations in our online tutorials posted on weblearn. We shall be available throughout your course should you have any queries that you need answering, and there will be online quizzes to test your knowledge of the more ‘inspirational’ topics if you feel like it! Our System: I’m sure you are familiar with the methods of interpreting radiographs of the chest and abdomen, but MSK radiology is slightly different. We present here our recommended systematic approach to MSK radiographs, but it is by no means a definite science, and if you wish to develop your own systematic approach then that’s absolutely fine by us (and the examiners). Just make sure that your approach ensures that you are thorough, precise and every radiograph is interpreted in an identical manner. This will improve your sensitivity/specificity when it comes to finding abnormalities!! Our system stems from TWO BASIC PNEUMONICS – which you will learn and cherish for ever and ever. OCSEP ABCS Learning these thoroughly will make your life MUCH easier and you’ll be less likely call upon the MDU as a junior doctor!! The OCSEP system O = Old Films (degeneration/progression) / Only Films (i.e. Lateral and A/P)??? C = CHECK NAME DATE SIDE PROJECTION S = Site? E = Extent? (does the film show all that you require?) MSK Radiology J. Wilson, E. Parker, I Al-Bakir, T Waterfield P = Penetration? (Could you be missing something from inadequate exposure?) This is a general system for interpreting any X-Ray and can be used for the CXR/AXR. The emphasis in MSK radiology is on the only film, site and extent aspects. You need to ask if other views are available because some abnormalities can only be seen in one particular plane, and large fractures can be missed!! You need to consider the site and extent of the radiograph, since some injuries can produce distant damage that may not be seen if a focused view is taken. For instance, a FOOSH may cause proximal radial/ulnar fractures. A view of the distal forearm/wrist would be a reasonable request (i.e. suspected Colles) but would not reveal any abnormalities because they aren’t in the picture! Remember, it’s your responsibility to ensure that a wider view is taken, inclusive of the elbow, in order to rule out more extensive damage. The ABCS system This is a system specific for MSK radiology and can be applied to any part of anatomy and any imaging modality. A = Alignment – Look at the contours of the bones and how they articulate with surrounding structures, starting with a general view (to catch any glaring abnormalities). Then trace the edges of each structure in view and look for deviation from normal anatomical position. There are landmarks that you can use in certain areas to help you (i.e. Shenton’s line in the hip), but subtle deviations can be difficult to spot until you are more familiar with normal appearances. Also, ensure you check for increased/decreased joint space. B = Bone – Take a general look of the bones in view, trying to spot any jagged edges, enlargement, displacement or colour changes (black = fracture/lytic/osteopaenic, whiter = infection/disordered tissue). Then (working from proxdistal or vice versa) trace the edges of the bone again, with particular attention to rough edges or enlargements and the shape of the articulating surfaces. Note any possible fractures, displacement, cysts, projections, areas of increased opacity. With more experience, you should be able to tailor your inspection in relation to the history (i.e. with a hx of FOOSH, remember to look properly at the scaphoid for fractures, as well as the proximal and distal radius/ulna). MSK Radiology J. Wilson, E. Parker, I Al-Bakir, T Waterfield C = Cartilage/Cortex – Start with a general inspection, then become more focused on tracing the cortex throughout the shaft of the bone(s) in view. You need to pay attention to the density, and be suspicious of colour changes (esp if soft tissues are affected). Small fractures are often only evident because of their appearance in the cortex. S = Soft Tissues – General inspection first looking for signs of swelling or loss of tissue (trauma). Trace the edges of the bone looking for periosteal reaction, and mass effect of the bone on the surrounding tissues (i.e. in osteosarcoma). Check for hardware or foreign bodies. Then put the pieces together and present!! **MAKE SURE that if you find one abnormality, that you KEEP LOOKING for other pathology as if you hadn’t found anything. DON’T MISS the 2nd/3rd fractures because you got too ahead of yourself!!** With practice you’ll get quicker, and with more experience you’ll recognise patterns and be more aware of the normal appearance. Try to ‘formally interpret’ as many radiographs as you can in the next 7 weeks, making good use of the SHOs/Regs. Try and see a bit of everything if possible, including MRIs and CTs. We hope that you enjoy the rotation, and feel free to get in touch with us if you have any questions on the systems or any online content. We’ll do our best to answer them! Happy Practising!