Ankle Anatomy and Radiography PDF

THE ANKLE  ANATOMY: http://www.wikiradiography.net/page/Ankle_Radiographic_Anatomy THE JOINT: The ankle joint is a synovial hinge joint (dorsiflexion/plantar flexion) Mortise Joint: gliding joint between the distal ends of the tibia and fibula and the proximal end of the talus 3 borde...

THE ANKLE  ANATOMY: http://www.wikiradiography.net/page/Ankle_Radiographic_Anatomy THE JOINT: The ankle joint is a synovial hinge joint (dorsiflexion/plantar flexion) Mortise Joint: gliding joint between the distal ends of the tibia and fibula and the proximal end of the talus 3 borders form the ankle mortise: Articular facet of the lateral malleolus Articular facet of the medial malleolus Inferior articular surface of tibia and superior margin of talus Tibiotalar joint Subtalar joint Distal tibiofibular joint- syndesmosis  THE LIGAMENTS: ► 3 main sets of ligaments: Medial: deltoid ligament Lateral: PTFL, ATFL and CFL Syndesmotic ligament ► Achilles injuries often happen during sport THE FAT PADS: ► Kager Fat Pads ► Normally appears lucent on lateral radiograph ► If borders are obliterated or distorted- this can indicate pathology in posterior ankle INDICATIONS: ► Trauma ► Cuts ► Pain ► Bruising ► Lumps ► Loss of function ► Foreign Body ► Deformity ► Swelling ► Reduced Range of Movement (ROM) ► Infections PREPARATION: ► Correct Patient Identification ► Pregnancy Check (if applicable) ► Explanation of Procedure ► Remove shoes, socks and jewellery (anklets, toe rings etc..) ► Patient to sit or lay on the xray table ► Lead apron  AP ANKLE: Xray: AP Ankle kVp: 55kVp mAs: 3.2mAs FFD: 100-110cm (depending on system) CR: 24x30 plate DR: Imaging Receptor Cassette: Long axis of image receptor parallel with long axis of the ankle Center midway between the medial and lateral malleoli at the level of the malleoli Centre: Laterally to skin margins Collimation: Include distal 1/3 of tib/fib and proximal ½ of metatarsals Pt laying on table, with legs extended Heel in contact with the image receptor Patient Position: Dorsiflex the ankle and foot enough to place long axis of foot in vertical position Adjust the ankle joint in the anatomic position with foot pointing straight to obtain a true AP projection Bontrager’s Handbook of Radiographic Positioning and Techniques EVALUATION CRITERIA AP ANKLE: ► Regional anatomy included – talus, proximal metatarsals and 1/3 distal tibia and fibula, including soft tissue ► Tibiotalar joint space open ► Medial aspect of mortise joint free of superimposition ► Joint not open laterally – some overlap of fibula with tibia and talus ► Density and contrast optimal to visualise bone & soft tissue, no motion https://radiopaedia.org/articles/ankle-ap-view-1  AP MORTISE OBLIQUE ANKLE: Xray: AP Mortise Oblique Ankle kVp: 55kVp mAs: 3.2mAs FFD: 100-110cm (depending on system) CR: 24x30 plate DR: Imaging Receptor Cassette: Long axis of image receptor parallel with long axis of the ankle Center midway between the medial and lateral malleoli Centre: At the level of the malleoli Collimation: Laterally to skin margins Include distal 1/3 of tib/fib and proximal ½ of metatarsals Pt laying on table, with legs extended Heel in contact with image receptor Patient Position: Dorsiflex the ankle so plantar surface of the foot is perpendicular (90degrees) to image receptor From the AP position rotate entire lower leg 15-20deg internally, placing intermalleolar plane parallel to image receptor Bontrager’s Handbook of Radiographic Positioning and Techniques  EVALUATION CRITERIA AP MORTISE OBLIQUE ANKLE: ► Regional anatomy included – proximal metatarsals and 1/3 distal tibia and fibula, including soft tissue ► Entire mortise joint in profile ► Lateral and medial talarmalleolar joint free of overlap ► The base of the 5th metatarsal is a common # site and shown well in this projection ► Density and contrast optimal to visualise bone & soft tissue, no motion  LATERAL ANKLE: Xray: Lateral Ankle kVp: 55kVp mAs: 3.2mAs FFD: 100-110cm (depending on system) CR: 24x30 plate DR: Imaging Receptor Cassette: Long axis of image receptor parallel with long axis of the ankle Centre: Center over medial malleolus Collimation: Four sides to the outer margins of the ankle Pt laying on table, with legs extended Patient Position: Roll Pt laterally onto affected side Dorsiflex the foot to prevent lateral rotation of the ankle Medial and lateral malleolus superimposed Consider positioning sponge to raise foot and facilitate true lateral Bontrager’s Handbook of Radiographic Positioning and Techniques  EVALUATION CRITERIA LATERAL ANKLE: ► Regional anatomy included – proximal metatarsals and 1/3 distal tibia and fibula, including soft tissue ► Fibular superimposing posterior half of tibia ► Tibiotalar joint open ► Talar domes superimposed ► Lateral malleolus superimposes talus ► Calcaneus in profile https://radiopaedia.org/articles/ankle-lateral-view-2 ► Density and contrast optimal to visualise bone & soft tissue, no motion  45 DEGREE OBLIQUE ANKLE: ► As per the Mortise Oblique View however the ankle is rolled 45deg ► This view demonstrates the distal ends of the tibia and fibula as well as the tibiofibular articulation Merrill’s Atlas of Radiographic Positioning and Radiologic Procedures HORIZONTAL BEAM LATERAL: https://radiopaedia.org/articles/ankle-series  WEIGHT BEARING VIEWS: Places the joint under normal weight-bearing conditions Assesses structural integrity of joint Often performed in follow-up imaging: Evaluation of fracture healing Evaluation of syndesmosis injury Mimic supine position upright Pathology ANKLE FRACTURES: ► Uni- Malleolar https://radiopaedia.org/cases/non- displaced-medial-malleolar-fracture?lang=gb ► Bi-Malleolar ► Tri-Malleolar – this includes lateral and medial malleolus as well as posterior tibia ANKLE DISLOCATION: ► When there is an ankle dislocation there is usually a fracture present as well ► An ankle dislocation is described according to the talus displacement ► The operation to fix a dislocation is called a reduction Posterior dislocation of the tibiotalar articulation Distal fibular fracture Medial and posterior malleolar fractures. https://radiopaedia.org/cases/ankle-fracture-dislocation-1?lang=gb STRESS VIEWS: ► Specialised view used to assess the integrity of the syndesmosis and deltoid ligament ► Ankle in AP position ► Second person- often referring physician places the ankle into inward (inversion stress) and then outward (eversion stress)  SYNDESMOSIS TREATMENT: https://www.researchgate.net/figure/Bimalleolar-ankle-fracture-treated-with- syndesmosis-only-fixation-the-post-fixation_fig3_51614589 AVASCULAR NECROSIS (AVN): ► When there is an ankle fracture or dislocation there is a chance of AVN ► It is the death of the bone tissue due to lose of blood supply ► Also known as osteonecrosis https://pubs.rsna.org/doi/10.1148/rg.252045709 ANKLE SURGERY: ► Arthroplasty = joint replacement ► Arthrodesis = joint fusion THE TIBIA AND FIBULA  ANATOMY: Tibia Tibial plateaus Intercondylar eminences Medial and lateral tibial condyles Tibial Tuberosity Medial Malleolus Fibula Apex Head Neck Lateral Malleolus Talus THE JOINTS: Patellofemoral joint Proximal and Distal Tibiofibular joint Medial and Lateral Femorotibial joints Talotibial INDICATIONS: Trauma (MVA, MBA) Cuts Acute Sporting Injury Bruising Pain Deformity Lumps Swelling Foreign Body Infections Previous Surgery  PREPARATION: Correct Patient Identification Pregnancy Check (if applicable) Explanation of Procedure Remove necessary clothing, gown with opening to the back Patient to lay on the xray table Lead apron  AP TIB/FIB: Xray: AP Tib/Fib kVp: 55kVp mAs: 5mAs FFD: 100cm/110cm CR: 35x43 plate DR: Imaging Receptor Image Receptor Consider lower leg diagonal across image receptor to ensure both knee and ankle joint are included. If Position: patient is tall you may need two films to demonstrate both knee and ankle joints adequately Centre: To mid shaft of lower leg Proximal to include knee joint, distal to include ankle joint. Approx. 3cm past each joint. Collimation: Medial/lateral to include soft tissue. Pt supine with both legs extended/ one leg (I find both easier) Patient Position: Rotate leg so that femoral condyles are parallel with image receptor Dorsiflex the ankle until foot is vertical Merrill’s Atlas of Radiographic Positioning and Radiologic Procedures EVALUTAION CRITERIA AP TIB/FIB: Regional anatomy included – distal femur to talus, including soft tissue Ankle and knee joints included and in AP position Tibiotalar joint space open Femoral and tibial condyles should appear symmetrical Patella superimposed on midline of femur Proximal and distal fibula slightly superimposed on tibia Density and contrast optimal to visualise bone & soft tissue  LATERAL TIB/FIB: Xray: Lateral Tib/Fib kVp: 55kVp mAs: 5mAs FFD: 100cm/110cm CR: 35x43 plate DR: Imaging Receptor Image Receptor Consider lower leg diagonal across image receptor to ensure both knee and ankle joint are included. If Position: patient is tall you may need two films to demonstrate both knee and ankle joints adequately Centre: To mid shaft of lower leg Collimation: Four sides to the outer margins of the leg Pt supine with affected leg extended Roll Pt towards affected leg, with the other leg either in front or behind for support Knee flexed to ensure true lateral position Patient Position: Rotate body to place patella perpendicular (90-degrees) to image receptor Superimpose medial and lateral malleoli Merrill’s Atlas of Radiographic Positioning and Radiologic Procedures EVALUATION CRITERIA LATERAL TIB/FIB: Regional anatomy included – distal femur to talus, including soft tissue Femoraltibial joint space Tibiotalar joint space Femoral and tibial condyles should be superimposed Fibular distally superimposing posterior half of tibia Lateral Malleolus superimoses talus Density and contrast optimal to visualise bone and soft tissue PATHOLOGY- LOWER LEG FRACTURES: The importance of 2 views at 90deg to each other EXTERNAL FIXATIONS: Used in complex fractures Temporary stabilisation until surgical treatment can be safely performed Used in paediatrics when pins could damage growth plate  Open Tib/Fib Fracture Patient presentation: 7y M Road traffic accident. Child bought unconscious with profuse bleeding from the left lower leg. https://radiopaedia.org/cases/open-tibia-and-fibula-fracture INTERNAL FIXATIONS: Intramedullary nailing Pin and plate ORIF PAGET’S DISEASE: Metabolic disease – the body absorbs old bone and forms abnormal new bone Bone is weakened, deformed and more prone to fractures Is affects pelvis, skull, femur, tibia and spine Thickened cortex with coarsened trabeculae W. H. O. Classification WHO Classification of Tumours Editorial Board, Who Classification of Tumours Editorial. Soft Tissue and Bone Tumours. (2020) EXOSTOSIS: Benign bone tumour or developmental anomaly Overgrowth of bone and cartilage extending from the surface Frequently an incidental finding found in teen years Grows from epiphyseal plate parallel to long bone  EWING’S SARCOMA: Malignant Occurs in young patients 10-20 years old Arises in medullary cavity/ bone marrow of long bones Aggressive appearance: Moth eaten, destructive, lucent lesions in the shaft of long bones Wide zone of transition/ poorly defined margin Soft tissue component REFERENCES: Bontrager, K. L. (2005) Textbook of Radiographic Positioning and Related Anatomy. (6th edn.) St Louis: Mosby. Eisenberg, R. L. (2003) Comprehensive Radiographic Pathology (3rd edn.) St Louis: Mosby. McQuillen-Martensen, K. (1996) Radiographic Critique. Philadelphia : W.B. Saunders. Weir, J. & Abrahams, S. P. (2003) Imaging Atlas of Human Anatomy (3rd ed). London: Mosby. http://www.wikiradiography.net https://radiopaedia.org https://www.radiologymasterclass.co.uk/