Joints and procedures review
What is the CR angle for PA Axial Caldwell Projection for facial bones? where does it exit? where are the petrous ridges?
Angle of CR is 15 degrees caudad exits the Nasionnn petrous ridges are in the lower 1/3 of the orbits frontal sinus, maxillae sinus crista galli nasal spine orbital rim zygote bones
how many degrees is the head rotated on oblique inferior superior tangential projection for zygomatic arches?
IOML is parallel rest head on vertex rotate head 15 degrees toward side to examined also tilt chin 15 degrees toward side of interest
Sims position
a recumbent position with the patient lying on the left anterior side (semi‐prone) with the left leg extended and the right knee and thigh partially flexed; often used to insert a rectal enema tip prior to a barium enema study
In lateral skull position where is the CR located?
center the CR 2 in above EAM or halfway between the labella and inion ss: sella turcica anterior and posterior clinoid processes
Where are the petrous ridges to be projected on a PA skull projection?
directly into the orbits
What sinuses are seen in the SMV paranasal projection?
ethmoid and sphenoid
What is the procedure for the SMV skull basal projection? I s the IOML parallel to the IR? where is the CR?
extende neck rest on vortex center MSP perp to IR IOML is positioned parallel to IR CR: perp to IOML entering midway between angle of mandible 1.5 inches inferior to mandibular symphysis structures seen: base of skull sphenoid sinus atlas, odontoidal process maxillary
What sinuses are viewed in PA Axial Caldwell projection? what is the angle for the CR where does it exit?
frontal, ethmoid and maxillary sphenoid are not seen because they located directly behind ethmoid sinus 15 caudad exiting the nasion
What sinuses are seen on lateral view of paranasal sinuses?
frontal, sphenoid, maxillae, ethmoid
For the axiolateral oblique projection mandible what is the best way to demonstrate the ramus? body? mentum? general survey of the mandible? what angle of CR?
head is in true lateral position to see the body: rotate head 30 deg mentum: 45 deg rotation general survey: 10-15 deg rotation CR 25 deg cephalic from IPL
Where is the tragus located
outside of the ear
Where should the petrous ridges be projected on parietoancanthial (waters method) projection for facial bones?
petrous ridges are projected just below maxillae sinus
how do you position pt for PA or PA axial mandible ? where is the CR projected ? CR for axial?
pt forehead and nose against IR tuck chin bringing OML perpendicular to IR align MSP per to midline perp to IR CR to exit junction of lips Axial: CR 20-25 cephalic centered to acanthionn rami and lat portions visualized
lithotomy position
pt positioned laying down with knees and hips lifted and rotated externally
In the zygomatic arches with SMV projection, where is the CR ? Is the IOML parallel or perpendicular to the IR??
the CR is midway between zygomatic arches, at a level of 1,5 inches inferior to mandibular symphysis IOML is parallel to IR
What is the angle for the CR for modified towne's method for zygomatic arches?
tuck pt chin CR 30 degree caudad to OML center CR 1 inch superior to glabella
Bicondylar joints*
Bicondylar joints usually provide movement in a single direction. They can permit limited rotation. Bicondylar joints are formed by two convex condyles, which may be encased by a fibrous capsule. Two examples of bicondylar joints are the knee (formerly clas- sified as ginglymus) and the temporomandibular joint (TMJ).
Q 98.7: The position illustrated in Figure 6-4 can be used successfully to demonstrate the PA oblique sternum barium-filled pylorus and duodenum left anterior ribs A 1 only B 1 and 2 only C 2 and 3 only D 1, 2, and 3
Explanation The Correct Answer is: D The RAO position is shown. The barium-filled pylorus and duodenum are well demonstrated in this position, and the esophagus can be projected between the vertebrae and heart in this position. This RAO position is also used to superimpose the sternum onto the heart shadow to provide uniform density throughout the sternum. The degree of obliquity depends on the patient's body habitus—greater obliquity is required for thinner chests. The RAO position is also used to see axillary portions of left anterior ribs; in the anterior oblique positions, the affected side is away from the IR. (Frank, Long, and Smith, 11th ed., vol. 1, p. 470)
Synovial Joints
Synovial joints are freely movable joints, most often found in the upper and lower limbs, which are characterized by a fibrous capsule that contains synovial fluid. The ends of the bones that make up a synovial joint may make contact but are completely separate and contain a joint space or cavity, which allows for a wide range of movement at these joints. Synovial joints are generally diarthrodial, or freely movable.
Ginglymus (hinge) joints
The articular surfaces of ginglymi, or ginglymus (jin′-gli-mus) joints, are molded to each other in such a way that they permit flexion and extension movements only. The articular fibrous capsule on this type of joint is thin on surfaces where bending takes place, but strong collateral ligaments firmly secure the bones at the lateral margins of the fibrous capsule. Examples of ginglymi include the interphalangeal joints of fingers and toes and the elbow joint
What is the purpose of a modified waters projection for facial bones? How is the OML positioned?
provides a less distorted and foreshortening view of the orbital rims petrous ridges are in the lower half of maxillae sinus OML forms a 55 degree angle with IR
In parietoacanthial (waters) projection for facial bones how is the pt positioned? what is visualized
Adjust patients head until the MML is perpendicular to plane of IR. OML forms a 37 degree angle with table/IR CR perp and exit ancanthion IOM petrous ridge are inferior to maxillary sinus nasal septum zygote bones dens in foramen magnum
For the AP axial projection (townes method) for mandible what is the angle on CR? not the same as usual what is seen?
Angle is 35-42 degrees caudad centered at glabella condyloid processes on mandible and TM fossae
Ellipsoid (condylar) joints
In the ellipsoid (e-lip′-soid) joint, movement occurs primarily in one plane and is combined with a slight degree of rotation at an axis at right angles to the primary plane of movement. The rotational movement is limited by associated ligaments and tendons. This type of joint allows primarily four directional movements: flexion and extension and abduction and adduction. Circum- duction movement also occurs; this results from conelike sequen- tial movements of flexion, abduction, extension, and adduction. Examples of ellipsoid joints include the metacarpophalangeal joints of the fingers, wrist joint, and the metatarsophalangeal joints of the toes.
Sellar (saddle) joints
The term sellar (sel′-ar), or saddle, describes this joint structure well in that the ends of the bones are shaped concave-convex and are positioned opposite each other (Two saddle-like structures fit into each other.) Movements of this biaxial type of sellar joint are the same as for ellipsoidal joints—flexion, extension, adduction, abduction, and circumduction. The best example of a true sellar joint is the first carpometa- carpal joint of the thumb. Other sellar joints include the ankle and the calcaneocuboid joints. Although the ankle joint was classified as a ginglymus in earlier references, current references classify it as a sellar joint.*
For the PA projection of the skull where is CR ? what structure is seen in this image? where does the CR exit?
frontal bone crista galli auditory canals, anterior ethmoid sinus petrous ridges fill the orbits to supraorbital margins dorsum sellae exit the glabella
In the PA Axial Haas projection of facial bones what structures are visualized? Where is the CR?
occipital bone, posterior clinoid foramen magnum dorsum sellae The CR is angled 25 deg cephalic passing through the level of the EAM exit 2.5 above the nasion. Pt neck is flexed OML perpendicular to IR
Fowler's position -
supine position with the head higher than the feet
Where do you center for lateral facial bones? what is visualized?
zygoma midway between outer cants and EAM superimposed facial bones wing of sphenoid orbital roofs sella turcica zygoma mandible frontal sinus maxillary sinus
What facial bones are seen in the parietoacanthial projection(Waters)?
zygomatic prominence body of maxilla( max sinus) bony nasal septum:(perp plate of ethmoid and vomer bone) zygomatic arch coronoid process condyle head mastoid process pf temporal bone foramen magnum
What is the projection for the Ap Axial Towne's projection of the skull?
80-85 kv OML perp to IR (if unable to flex neck align IOML perp) CR is 30 deg caudad to OML Center at MSP 2.5 inches above the glabella ss: occipital bone petrous pyramids foramen magnum dorsum sellae posterior clinics are the shadow
Spheroidal (ball and socket) joints
The spheroidal (sfe′-roid), or ball and socket, joint allows the great- est freedom of motion. The distal bone that makes up the joint is capable of motion around an almost indefinite number of axes, with one common center. The greater the depth of the socket, the more limited is the movement. However, the deeper joint is stronger and more stable. For example, the hip joint is a much stronger and more stable joint than the shoulder joint, but the range of movement is more limited in the hip. Movements of spheroidal joints include flexion, extension, abduction, adduction, circumduction, and medial and lateral rotation. Two examples of ball and socket joints are the hip joint and the shoulder joint.
3. Trochoid (pivot) joints
The trochoid (tro′-koid) joint is formed by a bony, pivot-like process that is surrounded by a ring of ligaments or a bony structure or both. This type of joint allows rotational movement around a single axis. Examples of trochoid joints are the proximal and distal radio- ulnar joints of the forearm, which demonstrate this pivot move- ment during rotation of the hand and wrist. Another example is the joint between the first and second cervical vertebrae. The dens of the axis (C2) forms the pivot, and the anterior arch of the atlas (C1), combined with posterior liga- ments, forms the ring
Plane (gliding) joints as is described in
This type of synovial joint permits the least movement, which, as the name implies, is a sliding or gliding motion between the articulating surfaces. Examples of plane joints are the intermetacarpal, carpometa- carpal, and intercarpal joints of the hand and wrist. The right and left lateral atlantoaxial joints between C1 and C2 vertebrae are also classified as plane, or gliding, joints; they permit some rota- tional movement between these vertebrae
In parietoacanthial transoral projection (open mouth waters) what sinuses are seen?
all four ethmoid sphenoid maxillae frontal
What is visualized in the picture?
radiograph 11-81 E. Foramen ovale of sphenoid F. Foramen spinosum of sphenoid G. Foramen magnum H. Petrous pyramid of temporal bone I. Mastoid portion of temporal bone J. Sphenoid sinus in body of sphenoid K. Condyle (head) of mandible L. Posterior border (vertical portion) of palatine bone M. Vomer or bony nasal septum N. Right maxillary sinuses O. Ethmoid sinuses Facial Bones—Frontal View (Fig. 11-82) A. Left nasal bone B. Frontal process of left maxilla C. Optic foramen D. Superior orbital fissure E. Inferior orbital fissure F. Superior and middle nasal conchae of ethmoid bone G. Vomer bone (lower portion of bony nasal septum) H. Left inferior nasal conchae I. Anterior nasal spine J. Alveolar process of left maxilla K. Alveolar process of left mandible L. Mental foramen M. Mentum or mental protuberance N. Body of right mandible O. Angle (gonion) of right mandible P. Ramus of right mandible Q. Body of right maxilla (contains maxillary sinuses) R. Zygomatic prominence of right zygomatic bone S. Outer orbit portion of right zygomatic bone T. Sphenoid bone (cranial bone)
Trendelenburg's position -
supine position with the head tilted downward
