Radiographic Positioning & Procedures I - Lower Extremities PDF

RADIOGRAPHIC POSITIONING AND RADIOLOGIC PROCEDURES I Lower Extremities Sesamoids POSITION (OF PATIENT & FILM (SIZE & REFERENCE...

RADIOGRAPHIC POSITIONING AND RADIOLOGIC PROCEDURES I Lower Extremities Sesamoids POSITION (OF PATIENT & FILM (SIZE & REFERENCE STRUCTURE EVALUATION PROJECTION CENTRAL RAY ORIENTATION) POINT SHOWN CRITERIA PART) Lewis Method 8 x 10 inches Lewis Method Lewis Method Lewis Method Tangential Projection ⤷Patient in prone position. (18 x 24 cm) ❖Perpendicular and ❖ Shows a ⤷ Sesamoids free of Lewis and Holly Methods Affected ankle elevated on crosswise for tangential to the 1st tangential any portion of the 1st sandbags for stability and multiple metatarsophalangeal projection of the metatarsal - folded towel under the exposures on 1 metatarsal head in Metatarsal heads knee. IR. profile and ⤷Rest the great toe on the sesamoids. table in dorsiflexion and adjust it to place the ball of the foot perpendicular to the horizontal. Center the IR Lewis Method to the 2nd metatarsal. Holly Method ⤷Patient seated on the table with the medial border of the foot adjusted in vertical position and plantar surface at an angle of 75 degrees with the plane of the IR. ⤷Patient holds toes in flexed position with strips of gauze Holly Method bandage. ⤷The central ray is directed perpendicular to the head of the 1st metatarsal bone. 1  FOOT AP OR AP AXIAL PROJECTION ❖Patient in supine. Flex the 10 x 12 inch Directed one of two ❖AP ❖ No rotation of the knee and place the foot on (24 x 30 cm) ways: (dorsoplantar) foot top of the IR. lengthwise 1. 10 degrees toward projection of the ❖Equal amount of ❖Position the IR under the the heel to the base tarsal anterior to space between the of the third the talus, patients foot center to the adjacent midshafts of metatarsals, or metatarsals, and base of the 3rd metatarsal the second through 2. perpendicular to phalanges. and adjust it so that the fourth metatarsals the IR and toward ❖ used for long axis is parallel to the ❖ Overlap of the the base of the third long axis of the foot. localizing foreign second through fifth metatarsal. bodies, metatarsal bases Radiographs may be obtained by ❖determining the ❖ Visualization of directing the central ray perpendicular to the plane of the IR or by angling the location of the phalanges and central ray 10 degrees posteriorly. fragments in tarsals distal to the fractures of the talus, as well as the metatarsals and metatarsals. the anterior tarsals, and. 2  ❖performing general surveys of the bones of the foot. AP OBLIQUE PROJECTION ❖Patient in supine. Flex the 10 x 12 inch ❖Perpendicular to ❖the cuboid and ❖Third through fifth Medial rotation knee of the affected side (24 x 30 cm) the base of the 3rd the calcaneus; metatarsal bases free enough to have the plantar lengthwise metatarsal ❖ the cuboid and of superimposition surface of the foot rest the fourth and fifth ❖Lateral tarsals with firmly on the table. metatarsals; Iess superimposition ❖Place IR under the foot ❖ the cuboid and than in the AP parallel with its long axis the lateral projection center to midline of the cuneiform; and ❖ Lateral foot at the level of the base ❖ the talus and tarsometatarsal and of the 3rd metatarsal. intertarsal. the navicular bone. ❖Rotate the leg medially ❖ Sinus tarsi ❖The cuboid is until the plantar surface of ❖ Tuberosity of the shown in profile. the foot forms an angle of ❖The sinus tarsi is fifth metatarsal 30 degrees to the plane of also well ❖ Bases of the first the IR Increasing the angle of the foot more than 30 demonstrated. and second degrees tends the lateral metatarsal cuneiform to be thrown ❖ Equal amount of over the other cuneiforms. space between the shafts of the second through fifth metatarsals. AP OBLIQUE PROJECTION ❖Patient in supine. Flex the 10 x 12 inch ❖Perpendicular to ❖Interspaces ❖ Separate first and Lateral rotation knee of the affected side (24 x 30 cm) the base of the third between the first second metatarsal enough to have the plantar lengthwise metatarsal and second bases surface of the foot rest metatarsals and ❖No firmly on the table. Position between the superimposition of of part. medial and the medial and ❖Place IR under the foot intermediate intermediate parallel with its long axis cuneiforms. cuneiforms center to midline of the foot ❖Navicular bone at the level of the base of more clearly the 3rd metatarsal. 3  ❖Rotate the leg laterally demonstrated than in until the plantar surface of the medial rotation the foot forms an angle of ❖ Sufficient density 30 degrees to the plane of to demonstrate the the IR phalanges, metatarsals, and tarsals. PA Oblique Projection Grashey Method ❖Patient in prone. Elevate IR 24 x 30 cm ❖Perpendicular to ❖Shows bones of Heel medially Medial or Lateral Rotation the affected foot on lenghtwise the base of the 3rd the foot and the rotated 30 degrees sandbags and folded towel metatarsal. interspaces of the ⤷First and second under the knee. proximal ends of metatarsal bases free ❖Patient foot placed its the metatarsals. of superimposition ⤷Medial cuneiform dorsal portion in contact projected without with IR parallel with its long superimposition axis center to the base of ⤷Navicular bone seen the 3rd metatarsal. in profile. ❖Rotate the heel medially Heel laterally rotated approximately 30 degrees to 20 degrees demonstrate interspaces ⤷Third thru fifth between the metatarsal. 1st metatarsal bases free and 2nd. of superimposition. ❖ Rotate the heel laterally ⤷Tuberosity of the 20 degrees to demonstrate fifth metatarsal and interspaces between 2nd & cuboid. 3rd, 3rd & 4th, 4th & 5th metatarsal. 4  LATERAL PROJECTION ❖Patient is lying on the 10 x 12 inch ❖Perpendicular to ❖Perpendicular to ❖Metatarsals nearly Mediolateral table turning towards the (24 x 30 cm) the base of the third the base of the superimposed affected side until the leg lengthwise metatarsal third metatarsal. ❖ Distal leg and foot are lateral with ❖Fibula overlapping opposite leg behind the the posterior portion patient. of the tibia ❖ Elevate the patients knee ❖ Tibiotalar joint to place the patella ❖Sufficient density perpendicular to horizontal with sandbag support under to demonstrate the the knee, then center the superimposed tarsals mid area of the foot with and metatarsals The lateral (mediolateral) projection is the long axis parallel with routinely used in most radiology the long axis of the IR. departments because it is a comfortable Dorsiflex the foot to form position for the patient to assume. 90 degree angle with lower leg. LATERAL PROJECTION ❖Patient is supine then 10 x 12 inch ❖Perpendicular to ❖Shows a true ❖Metatarsals Lateromedial patient turn unaffected side (24 x 30 cm) the base of the third lateromedial usually more until affected leg and foot lengthwise metatarsal projection of the superimposed than placed. foot, ankle joint, in the medio-lateral ❖Elevate the patients knee and distal ends of image, depending on to place the patella the tibia and the transverse arch perpendicular to horizontal, fibula. of the foot then center the IR to mid ❖ Distal leg area of the foot with the ❖Fibula overlapping long axis parallel with the the posterior portion long axis of the IR. of the tibia Whenever possible, lateral projections of ❖ Tibiotalar joint the foot should be made with the ❖Sufficient density medial side in contact with the IR. to demonstrate the superimposed tarsals and metatarsals. 5 Lateral Projection Weight Bearing ❖ Patient in upright 24 x 30 cm ❖Perpendicular to a ❖Shows a ❖Superimposed Method (Standing) preferably in a low riser with lengthwise point just above the lateromedial plantar surface of the for Longitudinal Arch IR groove. If not available base of the 3rd projection of the metatarsal heads use blocks to elevate the metatarsal. bones of the foot ❖Entire foot and foot to the level of x-ray with weight distal leg tube. bearing. This ❖Fibula overlapping ❖ Place IR vertically on the projection is also the posterior portion IR groove of the stool or used to of the tibia between blocks. Patient demonstrate the ❖ Sufficient density stand in natural position one structur.al status of longitudinal arch. to visualize the foot on each side of the IR superimposed tarsals with weight of body equally and metatarsals. distributed on the feet AP Axial Projection Weight Bearing ❖Patient in standing upright 24 x 30 cm ❖Angled 10 degrees ❖Demonstrate a ❖Both feet centered Method (Standing) position. crosswise for towards the heel is weight bearing AP on the image ❖Place IR on the floor and both feet on optimal. A minimum axial projection of ❖Phalanges, one IR of 15 degrees is both feet have the patient stand on metatarsals, and the IR with the feet usually necessary to permitting an distal tarsals. centered on each side, have enough room accurate ❖Correct right and weight of the body equally to position the tube. evaluation and left marker distributed on the feet. CR positioned comparison of the placement and a Right and left markers must between the feet at tarsals and weight bearing be placed on the IR. the level of the base metatarsals. marker of the 3rd ❖Correct exposure metatarsal. technique to visualize all the components AP AXIAL PROJECTION WEIGHT- ❖Patient in upright standing 10 x 12 inch 1st Exposure ❖Shows a weight- ❖All tarsals BEARING COMPOSITE METHOD – position standing on a (24 x 30 cm) ⤷Tube in front of the bearing axial ❖ Shadow of the leg Standing comfortable height in a low lengthwise patient adjusted for projection of all not overlapping the stool or the floor. a posterior bones of the foot. tarsals ❖Adjust the IR under the angulation of 15 The full outline of ❖ Foot not rotated degrees, with the foot is foot and center its midline ❖ Tarsals, central ray to the projected free of to long axis of the foot. To base of the third the leg. metatarsals and toes prevent superimposition of metatarsal with the with similar densities the leg shadow, on that of opposite foot the ankle joint, patient place 6  the opposite foot backward backward. Patient to for exposure of the forefoot carefully maintain and one foot forward for the the position of the exposure of the hind foot or affected foot; calcaneus. 2nd exposure. ⤷Place the foot one step forward Move the tube behind the patient, adjust it for Composite AP Axial, Posterior an anterior angulation of 15 degrees angulation of 25 degrees, and direct the central ray to the to the posterior surface of the ankle. ⤷The central ray emerges on the plantar surface at the level of the lateral malleolus. Composite AP Axial, Anterior angulation of 25 degrees Congenital Clubfoot Three deviations of the None None None normal alignment of the Clubfoot is called Talipes Equinovarus foot 1. Plantar flexion and inversion of the calcaneus (equinus). 2. Medial displacement of the forefoot (adduction). 3. Elevation of the medial border of the foot (supination). 7  Kite Method ❖with AP and Lateral projections is used to demonstrate the anatomy of the foot and the bones or ossification centers of the tarsals and their relation to one another. AP Projection ❖Infant in a supine position 8 x 10 inches ❖Perpendicular to None None with hips and knees flexed (18 x 24 cm) the tarsals, midway to permit the foot to rest between the tarsal flat on the IR. Elevate the areas for a bilateral body on a firm pillow to projection. knee height to simplify both ❖An approximately gonad shielding and leg 15-degree posterior adjustment. angle of the central ❖Rest the feet flat on the IR is generally required Demonstrate the degree of adduction of with the ankles extended to be perpendicular the forefoot and the degree of inversion slightly to prevent to the tarsals. of the calcaneus. superimposition of leg ❖ Kite stressed the shadow. Hold the infants importance of knee together so that the directing the central legs are exactly vertical. ray vertically to ❖When the deformity is project the true too great to permit correct relationship of the placement of the legs and bones and foot for bilateral images, ossification centers. they must be examined separately. 8  Lateral Projection ❖ Patient on his or her side 8 x 10 (18 x 24 ❖Perpendicular to None ❖ No medial or (Mediolateral) in as near as lateral position cm) the mid tarsal area. lateral angulation of with uppermost limb flexed, the leg drawn forward. ❖ Fibula in lateral ❖Adjust the IR under the projection foot and place a support overlapping the under the knee to prevent posterior half of the angulation of the foot tibia ensuring lateral position. ❖ The need for Hold the foot in position repeat exam. If slight The Kite method lateral demonstrates with tape or protected variation in rotation the anterior talar subluxation and the hand. is seen in either degree of plantar flexion (equinus). image when compared with previous radiographs ❖ Sufficient density of the talus, calcaneus, and metatarsals to allow assessment of alignment variation. CALCANEUS Axial Projection ❖Patient supine or seated 8 x 10 inches ❖Directed to the ❖Shows an axial ❖Calcaneus and Plantodorsal with leg extended. (18 x 24 cm) midpoint of the IR projection of the subtalar joint ❖IR under the patients at a cephalic angle calcaneus. ❖ No rotation of the ankle centered to the of 40 degrees to the calcaneus midline of the ankle. Long long axis of the foot ❖the first or fifth strip of gauze placed around entering the base of metatarsals not the ball of the foot, grasping the third metatarsal. projected to the sides it to hold the ankle in right of the foot angle dorsiflexion. If the ❖ Anterior portion of ankle cannot be flexed to the calcaneus place the plantar surface of without excessive the foot perpendicular to IR, density over the elevate the leg on sandbag. posterior portion. Otherwise two 9  images maybe needed for the two regions of thickness. Axial Projection ❖ Patient in prone position. 8 x 10 inches ❖Directed to the ❖Shows an axial ❖Calcaneus and Dorsoplantar ❖Patients ankle elevated on (18 x 24 cm) midpoint of the IR projection of the subtalar joint sandbags. Adjust the height at a caudal angle of calcaneus and the ❖ Sustentaculum tali and position of sandbags 40 degrees to the subtalar joint. ❖ Calcaneus not under the ankle so that long axis of the foot, rotated patient can dorsiflex the entering the dorsal ❖the first or fifth ankle to place its long axis surface of the ankle joint. metatarsals not perpendicular to tabletop. projected to the sides Place IR against the plantar of the foot surface of the foot and ❖ Anterior portion of support in position with sandbag. the calcaneus without excessive density over posterior portion. Otherwise, two images may be needed for the two regions of thickness. Weight Bearing Coalition Method ❖Patient in upright standing ❖Angled exactly 45 None None position degrees anteriorly ❖Center the IR to the long and directed axis of the calcaneus with through the the posterior surface of the posterior surface of heel at the edge of the IR. the flexed ankle to a To prevent superimposition point on the plantar of the leg shadow, patient surface at the level place the opposite foot one of the base of the step forward. fifth metatarsal. Demonstrate calcaneotalar coalition also know as “coalition position” 10  Lateral Projection ❖ Have the supine patient 8 x 10 inches ❖Perpendicular to ❖ Shows the ankle ❖No rotation of the turn toward the affected (18 x 24 cm) the calcaneus. joint and the calcaneus side until the leg is Center about 1 inch calcaneus in lateral ❖Density of the approximately lateral. A distal to the medial profile. sustentaculum tali, support may be placed malleolus placing lateral tuberosity and under the knee. the CR at the soft tissue ❖ Adjust the calcaneus to subtalar joint. ❖ Sinus tarsi the center of the IR. Adjust ❖ Ankle joint and the IR so that its long axis is adjacent tarsals parallel with the plantar surface of the heel. ANKLE AP Projection ❖Patient in supine affected 8 x 10 inch (18 ❖Perpendicular ❖Shows a true AP ❖- Tibiotalar joint limb fully extended. x 24 cm) through the ankle projection of the space ❖Ankle joint in true AP lengthwise or joint at a point ankle joint, the ❖ Ankle joint 24 x 30 cm midway between the distal ends of the position, then flex the foot centered to exposure crosswise for 2 malleoli. tibia and fibula, and ankle enough to place area images on one and the proximal the long axis of the foot in ❖ Talus slightly IR portion of the talus near vertical position. overlapping the distal fibula ❖No overlapping of the medial talo malleolar articulation ❖Medial and lateral malleoli ❖Talus with proper density ❖ Soft tissue LATERAL PROJECTION ❖Supine patient turn to the 8 x 10 inch (18 ❖Perpendicular to ❖ Shows a true ❖ Ankle joint Mediolateral affected side until the ankle x 24 cm) the ankle joint, lateral projection centered to exposure is lateral. entering the medial of the lower third area ❖ Long axis of the IR is malleolus of the tibia and ❖Tibiotalar joint well parallel to the long axis of fibula, the ankle visualized, with the the leg and center it to the joint, and the medial and lateral ankle joint. Ensure that tarsals. 11  lateral surface of the foot in talar domes contact with the IR. superimposed Dorsiflex the foot and ❖ Fibula over the adjust it in lateral position. posterior half of the tibia ❖ Distal tibia and fibula, talus, and adjacent tarsals ❖Density of the ankle sufficient to see the outline of distal portion of the fibula. LATERAL PROJECTION ❖Supine patient turn away 8 x 10 inch (18 ❖Perpendicular ❖Shows a lateral ❖Ankle joint Lateromedial from the affected side until x 24 cm) through the ankle projection of the centered to exposure the leg is lateral joint, entering 1/2 lower third of the area ❖Long axis of the IR is inch (1.3 cm) tibia and fibula, ❖Tibiotalar joint well parallel to the long axis of superior to the the ankle joint, visualized, with the the leg and center it to the lateral malleolus. and the tarsals. medial and lateral ankle joint. talar domes superimposed ❖ Fibula over the posterior half of the It is often recommended that the lateral tibia projection of the ankle joint be made ❖Distal tibia and with the medial side of the ankle in fibula, talus, and contact with the IR. adjacent tarsals ❖Density of the ankle sufficient to see the outline of distal portion of the fibula 12 AP Oblique Projection ❖Patient in supine position 8 x 10 inch (18 ❖Perpendicular, ❖The 45-degree ❖ Distal tibia, fibula Medial Rotation affected extended. x 24 cm) entering between medial oblique and talus ❖Center ankle joint to the the malleoli. projection ❖Distal tibia and IR and adjust it so that the demonstrate the fibula overlap some long axis is parallel with long distal ends of the of the talus axis of the leg. Dorsiflex the tibia and fibula, ❖ Talus and distal foot enough to place the parts of which are tibia and fibula ankle at nearly right-angle often adequately flexion. Assist the patient to superimposed over penetrated rotate the entire leg and join the talus. ❖ Tibiofibular t 45 degrees medially. Tibiofibular articulation should articulation also be demonstrated AP Oblique ❖ Patient in supine position 8 x 10 inch (18 ❖Perpendicular, ❖Lateral rotation ❖Subtalar joint Lateral Rotation extended x 24 cm) entering the ankle oblique projection ❖Calcaneal sulcus ( ❖ Place the plantar surface joint midway is useful in superior portion of of the foot in the vertical between the determining the calcaneus) position and laterally rotate malleoli fractures and the leg and foot 45 degrees demonstrating the and center the ankle joint to superior aspect of the IR. the calcaneus. AP Stress Study ⤷ Rupture of a ligament is AP Projection None None None demonstrated by widening stress studies of the joint space on the of the ankle side of the injury, when joint are without moving or rotating usually the lower leg from supine obtained position, the foot is forcibly following turned towards the opposite inversion or side. eversion injury ⤷Local anesthesia is injected to verify the into the sinus tarsi prior to presence of stress if the injury is recent. ligamentous tear 13  ⤷The physician holds or strap the foot when it must be turned into extreme stress for exposure. Mortise Joint ❖Patient in supine position 8 x 10 inch (18 ❖Perpendicular, ❖ The entire ankle ❖ Talus AP OBLIQUE Medial rotation affected limb extended. x 24 cm) entering the ankle mortise joint demonstrated with ❖Center ankle joint to the joint midway should be proper density IR. Assist the patient to between the demonstrated in ❖Entire ankle rotate the entire leg and malleoli. profile. The three mortise joint joint 15-20 degrees sides of the ❖ No overlap of the medially. mortise joint anterior tubercle of should be the tibia and the visualized. superolateral portion of the talus with the fibula. LEG AP Projection ❖Patient in supine position. 18 x 43 cm or ❖Perpendicular to ❖The resulting ❖Ankle and knee ❖Adjust the patient body 35 X 43 cm for the center of the leg image shows the joints on one or more two images on tibia, fibula, and AP projections so that pelvis is not rotated one IR Position adjacent joints. ❖ Ankle and knee then adjust the leg so that of patient the femoral condyles are joints without parallel with the IR and the rotation foot is vertical. ❖Proximal and distal articulations of the tibia and fibula moderately overlapped ❖ Trabecular detail and soft tissue for the entire leg 14  LATERAL PROJECTION ❖Patient in supine. 18 x 43 cm or ❖Perpendicular to ❖The resulting ❖Ankle and knee Mediolateral ❖Turn the supine patient 35 X 43 cm for the center of the leg. image shows the joints on one or more two images on tibia, fibula, and images towards the affected side one IR adjacent joints. ❖ Distal fibula lying with the leg on the IR then adjust the rotation of the over the posterior body to place the patella half of the tibia perpendicular to the IR. ❖ Slight overlap of the tibia on the proximal fibular head ❖ Ankle and knee joints not rotated ❖ Possibly no superimposition of femoral condyles because of divergence of the beam ❖Moderate separation of the tibial and fibular bodies, or shafts except at their articular ends. KNEE AP PROJECTION ❖Patient in supine and 10 x 12 inch ❖Directed to a ❖The resulting ❖Open femorotibial adjust the body so that (24 x 30 cm) point 1/2 inch (1.3 image shows an AP joint space pelvis is not rotated. cm) inferior to the projection of the ❖ Knee fully ❖With the IR under the patellar apex. knee structures. extended if patient' patients, flex the knee to Variable, depending condition permits locate the apex of the on the measurement ❖ Interspaces of patella and as the patient between the equal width on both extends the knee center the anterior superior sides if the knee is IR about ½ “below the iliac spine (ASIS) and Radiograph of the knee may be taken normal patellar apex. the tabletop; with or without use of a grid 15  ⤷ < 19 cm - 3 to 5 ❖ Patella completely degrees caudad superimposed on the (thin pelvis) femur ⤷ 19 to 24 cm – 0 ❖ No rotation of the degrees femur and tibia ⤷ ->24 cm - 3 to 5 ❖Slight degrees cephalad (large pelvis) superimposition of the fibular head if the tibia is normal ❖Soft tissue around the knee joint ❖Bony detail surrounding the patella on the distal femur LATERAL PROJECTION ❖Patient turn towards 10 x 12 inch ❖Center the IR to ❖Shows a lateral ❖ Femoral condyles Mediolateral affected side. For standard (24 x 30 cm) the central ray image of the distal superimposed lateral, have the knee ❖Directed to the end of the femur, ❖ Open joint space forward and extend the knee joint I inch (2.5 patella, knee joint, between femoral other limb behind. cm) distal to the proximal ends of condyles and tibia ❖Flex the knee 20 to 30 medial epicondyle the tibia and ❖ Patella in a lateral degrees to show maximum at an angel of 5 to 7 fibula, and profile volume of joint cavity. degrees cephalad. adjacent soft ❖ Open ❖To prevent fragment ❖This slight tissue. patellofemoral joint separation in new or angulation of the space unhealed patellar fracture, central ray will ❖ Fibular head and the knee should not be prevent the joint tibia slightly flexed more than 10 space from being superimposed (Over degrees obscured by the rotation causes less magnified image of superimposition, and the medial femoral under rotation condyle. causes more superimposition.) ❖ Knee flexed 20 to 30 degrees 16  ❖ All soft tissue around the knee ❖ Femoral condyles with proper density AP Projection Weight-Bearing Standing ❖Patient in upright with the 35 x 43 cm ❖Horizontal and ❖Shows the joint ❖No rotation of the back toward a vertical grid crosswise for perpendicular to the spaces of the knees device. bilateral image center of the IR knees. Varus and ❖ Both knees ❖Center the knees to the Position of entering to a point valgus deformities ❖ Knee joint space patient ½ inch below the can be evaluated. IR, toes straight ahead with centered to the feet separated enough for apices of the patella exposure area good balance. ❖ Adequate IR size ❖Patient stand straight to demonstrate the Leach, Gregg, and Siber recommended with knees fully extended longitudinal axis of that a bilateral weight-bearing AP and weight equally the femoral and tibial projection be routinely included in distributed on the feet. bodies or shafts. radiographic examination of arthritic Center IR ½ inch below the knees because it reveals narrowing of the patellar apices. knee joint spaces that appears normal in the non-weight bearing study PA Projection Rosenberg Method ❖Patient in standing 35 x 43 cm ❖Horizontal and ❖PA weight- ❖No rotation of the Weight-Bearing Standing Flexion position with the anterior crosswise for perpendicular to bearing method is knees aspect of the knee centered bilateral image center of the IR The useful for ❖Both knees to the vertical grid device. Position of CR is perpendicular evaluating joint ❖ Knee joint Position of part. patient to tibia and fibula. A space narrowing centered to the ❖ For direct PA projection, 10-degree caudal and exposure area have the patient stand angle is sometimes demonstrating upright with knees in used. articular cartilage contact with the grid device. disease. The image Center the IR at the level ½ is radiographing inch below the apices of the intercondyloid Note: For a weight-bearing study of a fossa. the patella. Patient grasp single knee, the patient puts full weight the edge of the grid device on the affected side and flex the knees to place the femur at 45-degree angle. 17  INTERCONDYLOID FOSSA PA Axial Projection Place the patient in one of 8 x 10 inches ❖Perpendicular to ❖ Shows the ❖Open fossa Holmblad Method three position: (18 x 24 cm) the lower leg, intercondyloid ❖ Posteroinferior 1. Standing with the entering the fossa of the femur surface of the affected knee flexed and midpoint of the IR and the medial femoral condyles resting on a stool at the side for all three position. and lateral ❖Intercondylar of radiographic table. intercondylar 2. Standing at the side of eminence and knee tubercle of the the table with the affected joint space intercondylar knee flexed and in contact ❖Apex of the patella eminence in with front of the IR. profile. It also not superimposing 3. Kneeling on top of states that the the fossa radiographic table as degree of flexion ❖No rotation evident originally described by used widens the by slight tibiofibular Holmblad. joint space overlap ❖For all positions, place the between the ❖Soft tissue in the IR against the anterior femur and the fossa and interspaces surface of the patients knee tibia and gives ❖Bony detail in the and center it to the apex of improved image of intercondyloid the patella. Flex the knee 70 the joint and eminence, distal degrees from full extension surfaces of the femur and proximal with 20-degree difference tibia and femur tibia. from the central ray PA Axial or “tunnel” projection required that the patient assume a kneeling position. 18  PA Axial Camp Coventry ❖Patient in prone and 8 x 10 inches ❖Perpendicular to ❖Demonstrate an ❖ Open fossa adjust the body so that it is (18 x 24 cm) the long axis of the unobstructed ❖ Posteroinferior not rotated. leg and centered to projection of the surface of the ❖Flex the knee to either a the knee joint (over intercondyloid femoral condyles 40- or 50-degree angle and popliteal fossa and the ❖Intercondylar rest the foot on a suitable depression). Angled medial and lateral eminence and knee support. Center the upper 40 degrees when intercondylar joint space half of the IR to the knee the knee is flexed 40 tubercle of the ❖ Apex of the patella joint to project the joint to degrees of 50 intercondylar degrees when the eminence. not superimposing the center of the IR. Adjust knee is flexed 50 the fossa Note: Intercondyloid fossa projection is the leg so that the knee has degrees ❖ No rotation also used to detect loose bodies (“joint no medial or lateral mice”) rotation. evident by slight tibiofibular overlap ❖Soft tissue in the fossa and interspaces ❖ Bony detail of the intercondylar eminbence, distal femur and proximal tibia AP Axial Beclere Method ❖Patient in supine and 8 x 10 inches ❖Perpendicular to ❖Shows the ❖Open intercondylar adjust the body so that it is (18 x 24 cm) the long axis of the intercondylar fossa not rotated. tibia entering the fossa, ❖Posteroinferior ❖Flex the affected knee knee joint ½ inch intercondylar surface of the enough to place the long below the patellar eminence and femoral condyles axis of the femur at an apex. knee joint. ❖ Intercondylar angle of 60 degrees to the eminence and knee long axis of the tibia. IR joint space under the knee and position ❖No it so that it coincide with the superimposition of central ray. Adjust the leg so the fossa by the of that femoral condyles are the patella equidistant from the IR. ❖ No rotation evident by slight tibiofibular overlap 19  ❖ Soft tissue in the fossa and interspaces ❖ Bony detail on the intercondylar eminence, dista femur and proximal tibia. PATELLA PA Projection ❖Patient in prone. If the 8 x 10 inches ❖Perpendicular to ❖PA projection of ❖Patella completely knee is painful place a (18 x 24 cm) the mid-popliteal the patella superimposed by the support under the thigh and area exiting the provides sharper femur leg to relieve pressure. patella. recorded detail ❖ Adequate ❖Center IR to the patella. than in the AP penetration for Adjust the position of the projection because visualization of the leg to place the patella of the closer patella clearly parallel with the plane of IR object-to-image through the by rotating the heel 5-10 receptor distance superimposing femur. degrees laterally ❖ No rotation Lateral Projection ❖Patient in lateral 8 x 10 inches ❖Perpendicular to ❖Shows a lateral ❖Knee flexed 5-10 Mediolateral recumbent position (18 x 24 cm) the IR entering the projection of the degrees ❖Patient to turn toward the knee at the mid patella and ❖Open affected side and place patellofemoral joint. patellofemoral patellofemoral joint support under the ankle. joint space. space Flex the unaffected knee ❖ Patella in lateral and hip and place profile unaffected foot in front of ❖Close collimation affected limb. The affected knee is flexed 5-10 degrees because increasing the flexion reduces the patellofemoral joint space. ❖Adjust the knee in lateral so that femoral epicondyles are superimposed and patella perpendicular. 20  PATELLA AND PATELLOFEMORAL JOINT Tangential Hughston Method ❖ Patient in prone with the 8 x 10 inches ❖Angled 45 degrees ❖Shows ❖Patella in profile foot resting on radiographic (18 x 24 cm) cephalad directed to subluxation of the ❖Open table. for unilateral patellofemoral joint. patella and patellofemoral ❖ IR under the patients 24 x 30 cm patellar fractures articulation crosswise for and allows knee then slowly flex the ❖ Surfaces of the bilateral radiographic affected knee so that the femoral condyles examination assessment of the tibia and fibula form 50-60 ❖ Soft tissue of the degree angle from the table femoral condyles. femoropatellar with the foot resting on the articulation collimator or support it in For a tangential radiograph of the patella, ❖ Bony recorded position. the patient maybe placed in any of the detail on the patella following body positions: prone, supine, and femoral condyle lying on the side, seated on the table, seated on the radiographic table with the leg hanging over the edge or standing Tangential Projection ❖ Patient in supine or 8 x 10 inches ❖Perpendicular to ❖Shows vertical ❖Patella in profile Settegast Method prone. Prone is preferable (18 x 24 cm) the patellofemoral fracture of the ❖ Open because the knee can be joint space if bone and the patellofemoral flexed to a greater degree perpendicular if not, articulating articulation and immobilization is central ray surfaces of the ❖ Surfaces of the easier. If the patient is angulated patellofemoral femoral condyles seated on the table, hold depending on the articulations.