Shoulder Flashcards
What are routine x-ray projections for the shoulder?
AP
Lateral (Y View)
What are routine x-ray projections for the clavicle?
AP
Axial
What are the clinical indications of the x-ray?
Shoulder trauma
Bony tenderness at the glenohumeral joint/region
Restriction of rotation
Instability
Suspected dislocation
AC jointinjury
Scapulatrauma
Suspected arthritis
Non-traumatic shoulder pain
AC joint injuries are graded up until what number?
6
In an AP clavicle x-ray, what would you call the lateral portion of the clavicle?
Distal clavicle
If you want to x-ray the right shoulder in a Y view lateral x-ray, how is the patient positioned?
The patient is in Right Anterior Oblique position
RAO
The side that is being x-rayed is the side you want against the image receptor
In an axial clavicle x-ray, what direction/angle is the x-ray beam facing?
X-ray is angled 15-20 degrees cephalad - i.e xray beam is positioned towards the head
What does cephalad mean?
Towards the head end
What does cordad mean?
Towards the tail end
How would a displacement fracture present of the clavicle?
Displacement fracture means one side has moved - normally up
What are additional projections of the shoulder?
AP Internal/External Rotation
AP Glenoid (Grashey)
Axial
What are additional projections of the shoulder?
Sternoclavicular Joint
Acromioclavicular joint
What are Hills-Sachs lesions?
type of fracture at the humeral head
What is the best x-ray to detect Hills-Sachs lesions?
AP internal rotation
What does en face mean?
facing the front
What does in profile mean?
facing the side
In AP internal rotation and the analogy of the ice cream. Is the ice cream sitting nicely on top or is it falling off the cone?
Sitting nicely on top
In an AP internal rotation x-ray of the shoulder, the lesser tuberosity is facing en face or in profile?
in profile
In an AP internal rotation x-ray of the shoulder, the greater tuberosity is en face or in profile?
en face
In an AP external rotation x-ray of the shoulder, with the analogy of the ice cream, is this sitting nicely on top or falling off?
Ice cream is falling off of the cone
What is the x-ray view that assess the Glenohumeral joint space?
AP Glenoid (Grashey) View
What shape is the clavicle in Grashey view?
S shaped (Chicken wing)
How is the patient positioned for a Right Grashey x-ray?
In a right posterior oblique position - RPO
Why would you perform an axial shoulder x-ray?
additional information when assessing dislocations and glenohumeral instability
relationship between the glenoid and humeral head and the acromion and coracoid processes
What is a sternoclavicular x-ray for?
To assess Sternoclavicular. These are to look at the SC joint
Pt is positioned closer to the image receptor to enable less distortion of the image. This can be in PA, RAO, LAO
Why would you do an Acromioclavicular joint x-ray for?
shouldertrauma
direct blows to the shoulder region
following a fall onto an adducted arm
suspecteddislocation
suspected arthritis
What is the normal joint space of the Glenohumeral joint?
3-6mm
What is the normal joint space of the Acromiohumeral Distance?
7-11mm
What is the normal joint space of the Acromioclavicular Joint?
2-4mm
What is the normal joint space of the Coracoclavicular Distance?
11-13mm
What could be indicative of decreased joint space in the Glenohumeral joint?
Degenerative Joint Disease (DJD), Arthropathies, Anterior or Posterior Dislocation
What could be indicative of decreased joint space in the Acromioclavicular Joint?
Degenerative Joint Disease (DJD)
What could be indicative of decreased joint space in the Acromiohumeral Distance?
Rotator Cuff Tear
What could be indicative of increased joint space in the Acromiohumeral Distance?
Subluxation, Dislocation
What could be indicative of increased joint space in the Coracoclavicular Distance?
ACJ Separation
What could be indicative of increased joint space in the Glenohumeral Joint?
Posterior Dislocation
What could be indicative of increased joint space in the Acromioclavicular Joint?
ACJ Separation, Clavicular Erosion/Absorption
What is Maloney’s arch?
the curve from the lateral border of the scapula to the medial humerus
This line can be disrupted with a posterior shoulder dislocation
What is a Rhomboid Fossa?
Roughened area along the inferior border of the medial clavicle, appears as a pronounced depression or crescent defect
Notch that looks like an erosion in the medial inferior clavicle
What does a Rhomboid Fossa look like on an x-ray and what is the clinical significance?
Delineated from clavicle by a band of increased density; notch on inferomedial clavicle
Clinical Significance - None – developmental variation
What is Sprengel’s Deformity?
Congenital elevation of the scapula
Complex deformity of the shoulder
How could Sprengel’s Deformity display on an x-ray?
elevation of one or both scapular
What is the clinical significance of Sprengel’s Deformity?
Klippel-Feil Syndrome
Spina Bifida
Kyphoscoliosis
Torticollis
Under development of the clavicle or humerus
What is a conoid tubercle enlargement?
Insertion site of the Conoid Ligament
Prominent and hypertrophied
X-ray: large outgrowth of the bone at the conoid tubercle of the clavicle with continuous cortex and normal bony matrix.
What is a Supraclavicular Foramen?
Osseus tunnel in the superior aspect of the distal 1/3 of clavicle
What causes it? - Anatomical variant Passage of supraclavicular nerve
X-ray: small, round, radiolucent foramen in the superior clavicle
Clinical Significance - Incidental finding
Reports of cause of supraclavicular nerve entrapment syndrome
What is the name of the accessory ossicle of the shoulder?
Os Acromiale
Where is the Os Acromiale located?
best seen on axial shoulder view
Small, round, bony structure with smooth cortical margins at the distal acromion
What is the clinical significance of Os Acromiale?
may cause shoulder impingement,rotator cuff tearor degenerative acromioclavicular joint disease
DDx:
normal AC Joint: acromion fusion may not occur till around 18-25 years of age.
degenerative ossicles
fracture of the acromion
calcific tendinosis of the supraspinatus
What are normal structures that can simulate pathology?
Nutrient Channels/foramina
Vacuum Phenomenon
Companion Shadow
What is a companion shadow?
soft tissue that overlies the bone
Common shadows include:
Rib Companion Shadow: Shadows of 1st and 2nd rib are present in approx 35% of population
Clavicle Companion Shadow: Thin line running along upper border of clavicle
Scapula Companion Shadow: Runs parallel to medial border of scapula
What is a vacuum phenomenon?
presence of intra-articular gas in the shoulder joint and they are very common.
X-ray: very common in ER - Circular or linear lucent appearance
What are Nutrient Channels/foramina?
a small tunnel through the cortex of a long bone containing a nutrient artery which supplies the bone.They are caused by nutrient artery enters a long bone via an obliquely orientated canal.
Anatomical variant
X-ray :
radiolucent line passing through the cortex into the medullary portion of the diaphysis of the bone.
Well-corticated edge
Directed AWAY from bone growth
Clinical significance:
mimic oblique fractures (#) on plain radiographs
Can Os Acromiale be bi-lateral?
Yes, they can be. 8% of people have Os Acromiale and 30% of them have it bilaterally
