RADIOLOGY EPONYMS

IMPORTANT X RAY SIGNS

General Orthopedics X ray signs in Scurvy: Wimberger ring, White line of Frankel (also seen in healing rickets and lead poisoning, methotrexate therapy and ), Trummerfeld zone, Pelkan spur, Pencil thin cortex, Corner sign X ray signs in Rickets: Widening/ splaying of the physis and cupping of the metaphysis X ray signs in : Pseudofractures/ looser’s zones, tri radiate and champagne glass pelvis, cod fish vertebrae Conditions with Looser’s zones: Osteomalacia (characteristic), Renal osteodystrophy, Fibrous dysplasia, Hyperthyroidism, Paget’s disease of bone, X-linked hypophosphatemia, Osteogenesis imperfecta X ray signs in Perthes disease: Sagging rope sign, Gage sign and Crescent sign (also seen in of head of femur) X ray signs in SCFE: Trethowan sign, Metaphyseal blanch sign of steel X ray features in Achondroplasia- Short interpedicular distance, bullet shaped vertebra, champagne glass pelvis X ray features in Nail patella syndrome- Hypoplastic or absent patella, bilateral posterior iliac horns (Fong’s prongs) and prominent anterior iliac spine Dripping candle wax appearance/ Flowing calcification- (Leri’s disease) X ray signs in Trochlear dysplasia: Crossing sign, Double contour sign Rugger jersey spine: Hyperparathyroidism, X ray signs in Hyperparathyroidism: Papper pot skull, Salt and pepper appearance (skull), sclerosis at the base of skull, Brown’s tumours, Rotting fence post appearance of femur, Sub- periosteal resorption of radial side of terminal and middle phalanges X ray signs in Ankylosing spondylitis: Romanus lesions of the spine (Shiny corner sign), Anderson’s lesion (Spinal pseudoarthrosis), Squaring of vertebrae, Bamboo spine appearance, Dagger spine appearance Pencil in cup appearance: Psoriatic arthropathy Ivory phalanx: Psoriatic arthropathy Martel/ G sign: Gouty arthritis Kissing spines: Baastrup’s disease (A degenerative change, bony proliferation between the spinous processes of closely aproximated adjacent vertebrae) X ray signs of Paget’s disease: circumscripta (cotton wool spots in skull), Tam o' Shanter sign (skull), Picture frame vertebra, Ivory vertebrae, Blade of grass or flame appearance (long bones), Brim sign Bone within bone appearance (Endobones)- Osteopetrosis, Sickle cell anemia, Thalassemia, Paget’s disease, Acromegaly, Lead poisoning, Growth arrest lines (infancy), Gaucher’s disease and congenital syphilis. Erlen Meyer Flask deformity- Osteopetrosis, Achondroplasia, Metaphyseal dysplasia (Pyle’s disease), Fibrous dysplasia, Rickets, Rheumatoid arthritis, Ollier’s disease, Thalassemia, Gaucher’s disease, Niemann-Pick disease White bone (sclerotic bone) disorders: Osteopetrosis, , , osteopathia striata, melorheostosis, Caffey’s disease, pyknodysostosis Fairbank’s triangle: Congenital coxa vara (classical), Non-union neck femur in children TB hip: Wandering acetabulum, Pestel and mortar appearance TB spine: Aneurysmal sign (Anterior TB), Concertina collapse (Central TB)

Risser’s sign:

Wormian bones: Idiopathic > Osteogenesis imperfect (commonest causes); Mnemonic “SODA PORCH”. S–Syndrome-Kinky hair syndrome O–Osteogenesis imperfecta D–Down syndrome A–Acro- P– O–Otopalatodigital syndrome R–Rickets C– H–Hypothyroidism/

Vertebrae plana: Langerhan cell histiocytosis (Eosinophilic granuloma), Ewing sarcoma, Leukemia/ Lymphoma, Gaucher’s disease, ABC, Infective spondylitis (TB)

Trauma Thurston Holland Fracture fragment- Type II and type IV physeal injuries Light bulb sign- posterior dislocation of shoulder Hill Sachs lesion- Recurrent shoulder dislocation Bankart’s lesion- Recurrent shoulder dislocation Sourcil sign- Massive retracted rotator cuff tear > Periarthritis Celery stalk appearance of distal femur- Chronic ACL tears (mucoid degenerations) and Congenital Rubella Fat pad sign- Undisplaced supracondylar fracture humerus Terry Thomas / David Letterman sign: Scapho-lunate dissociation due to ligamentous injury Spilled tea pot sign: Lunate dislocation Hawkins sign: Fracture talar neck for predicting avascular necrosis Battered baby syndrome: Metaphyseal Corner fractures, Metaphyseal Bucket handle fractures, Eggshell fractures, Subdural haemorrhages Spur sign: Both column fracture acetabulum Beheaded scottish dog sign (Oblique view) and Inverted Napoleon Hat sign (AP view): Spondylolisthesis

SOME IMPORTANT ANGLES, TRIANGLES, LINES AND INDICES

Southwick’s angle: SCFE Acetabular index: CDH Alpha and Beta angles: CDH (on ultrasonography) Kite’s angle: CTEV Singh’s index: For grading osteoporosis by quantifying trabeculae in neck femur Ward’s triangle: Femoral neck (significant for osteoporosis grading) Babecock’s triangle: Neck of femur (could be starting point of TB hip) Reimer’s index: CDH Center edge angle of Wiberg: CDH Fairbank’s triangle: Congenital coxa vara (classical), Perthes disease, Non union neck femur Neck shaft angle: Normal is 127 degrees Pauwell’s angle: Neck of femur fracture Hilgenreiner’s epiphyseal angle: Congenital coxa vara Shenton’s line: Normally a continuous line. Broken in any pathology that affects supra trochanteric area Bohler and Gissane’a angles: Calcaneum fractures Neutral triangle: Calcaneum Meary’s angle and calcaneal pitch: Pes planus and cavus Bauman’s angle and Anterior humeral line: Supra condylar humerus fracture Distal radius indices: Radial length, Volar tilt, Ulnar variance Gilula lines: Congruent arcs in normal wrist X ray Cobb’s angle and Mehta’s angle: Scoliosis Matta’s roof arc angle: Acetabular fractures Metaphyseal-Diaphyseal angle of Drenan: Blount’s disease

SOME X RAY VIEWS TO REMEMBER Axillary view: Lateral view of shoulder joint

West point axillary view: for Bankart’s lesion

Internal rotation view and Stryker notch view: for Hill Sachs lesion

Zanca view: Acromio-clavicular joint

Serendipity view: Sterno clavicular joint imaging to detect dislocation

Green span view: fractures of radial head and capitellum

Jones (AP) view elbow: Evaluation of reduction in supra condylar humerus fractures

Oblique view wrist and PA view wrist in ulnar deviation: Scaphoid fractures

Brewerton view: used to see metacarpal head fractures

Robert’s view: used for thumb CMC joint

Carpal tunnel view: for hook of hamate fractures

Ball catcher’s view: for visualizing erosions in RA hand

Judet views (Obturator oblique and Iliac oblique views): Acetabular fractures

Frog leg view: A modified method of taking lateral view of hip joint intra-operatively

Von Rosen view: CDH

Axial view, Skyline view and Merchant’s view: Patellar subluxation

Mortise view (ankle AP view in 15o internal rotation): Ankle injuries evaluation

Canale view: Talar neck fractures

Harris view of hind foot: Calcaneum fractures

Broden views: Intra-operative assessment in calcaneal fractures

Swimmer’s view: Cervical spine lateral view (shoulder pull down) to assess lower cervical spine (C6, C7 and T1 can be visualized)

Ferguson view: This is 20o caudo-cephalic AP view of lumbar spine used to detect compression of L5 by a large transverse process of L5 vertebra against sacrum (called as Far out syndrome)

EXTRA MARKS

Rule of two: In any injury x rays should always include one joint above and one joint below the level of trauma

Ottawa ankle rule: used to avoid unneeded radiographs after ankle injury (i.e. which patient needs X-ray after ankle injury?). Ankle X-ray is required if there is pain in malleolar region plus bony tenderness along the distal posterior edge (or tip) of medial or lateral malleolus or inability to bear weight for four steps.

Ottawa foot rule: X-ray foot is required if there is any pain in the midfoot zone plus bony tenderness at the base of the fifth metatarsal or at the navicular bone or inability to bear weight for four steps.