IMAGES Chapter 42 - Skeletal Trauma Flashcards
DIAGNOSIS ? [FIGURE 42.17]
BENNETT FRACTURE
A small corner fracture of the base of the thumb is noted, which involves the articular surface of the base of the thumb (arrow); this is serious injury that almost always requires internal fixation.
NORMAL or ABNORMAL ? IDENTIFY THE ASSOCIATED RADIOGRAPHIC SIGN. [FIGURE 42.41]
NORMAL AP VIEW OF THE SHOULDER
Note in this example of a normal shoulder that the hu_meral head slightly overlaps the glenoid_, which has been termed the crescent sign.
DIAGNOSIS ? [FIGURE 42.24]
LUNATE DISLOCATION
A. The lateral radiograph of the wrist shows the lunate (L) tipped off of the distal radius, whereas the capitate
(C) seems to be normally aligned in relation to the radius, yet
is dislocated from the lunate.
Compare this with the drawing in Figure 42.22C.
The anteroposterior (AP) view shows a pie-shaped lunate
(B) (L) rather than a lunate with a more rhomboid shape.
A pie-shapedlunate on the AP view is diagnostic of a perilunate or lunate dislocation.
DIAGNOSIS ? [FIGURE 42.50]
AVULSION OFF THE ISCHIUM
An AP view of the pelvis shows an area of cortical disruption and periostitis at the right ischium (arrow) in a patient complaining of pain at this site.
These findings are characteristic for an ischial avulsion and should not undergo biopsy.
DIAGNOSIS ? [FIGURE 42.10]
UNILATERAL LOCKED FACETS
The C6-C7 disc space is abnormally widened, and the C7 vertebra is posteriorly located in relation to C6. Also note the C7 facets, which are dislocated and locked on the C6 facets (arrow). When the facets are perched in this manner, it is termed locked facets, which are unilateral in this example.
DIAGNOSIS ? [FIGURE 42.30]
KIENBÖCK MALACIA
An AP view of the wrist reveals the lunate to be sclerotic and abnormal in shape. The lunate has collapsed because of aseptic necrosis. This is known as Kienböck malacia.
Note that the ulna is shorter than the radius, this is termed negative ulnar variance, which is often associated with Kienböck malacia.
DIAGNOSIS ? [FIGURE 42.40]
ANTERIOR SHOULDER DISLOCATION
An AP view of the right shoulder shows the humeral head to lie medial to the glenoid and inferior to the coracoid process (C).
This is diagnostic of an anterior dislocation of the shoulder.
DIAGNOSIS ? [FIGURE 42.46]
DISLOCATION OF THE HIP
A. An AP plain film of the left hip shows dislocation of the femoral head, which lies slightly superior to the acetabulum.
B. Fractures are easily identified on the CT scan. A cortical breakthrough the articular surface of the posterior acetabulum as well as the dislocation is identified.
DIAGNOSIS ? [FIGURE 42.47}
FRACTURE OF THE SACRUM
An AP view of the sacrum in this patient shows normal arcuate lines on the left side of the sacrum that are interrupted on the right side (arrows).
Interruption of these lines indicates a fracture through this portion of the sacrum.
DIAGNOSIS ? [FIGURE 42.56]
FEMORAL STRESS FRACTURE
A linear lucency with surrounding sclerosis is seen in the femoral neck in this jogger with hip pain. This is a severe femoral neck stress fracture.
DIAGNOSIS ? [FIGURE 42.37]
DISPLACED ELBOW FAT PADS
A. On the lateral view of this elbow, the posterior fat pad is faintly visible (arrow) and the anterior fat pad is elevated and anteriorly displaced (curved arrow). These findings indicate a fracture about the elbow that in an adult should be in the radial head.
B. An oblique view shows the fracture of the radial head (arrow). Even without seeing the fracture on the radiographs, it should be surmised to be present when the posterior fat pad is visualized in the setting of trauma. The elevated and displaced anterior fat pad has been termed a sail sign.
DIAGNOSIS ? [FIGURE 42.28]
SCAPHOID FRACTURE
A coronal T1WI of the wrist in a patient with snuffbox tenderness and a normal plain film shows a fracture of the mid-waist of the scaphoid (arrow).
DIAGNOSIS ? [FIGURE 42.15]
A. This patient had been in an auto accident and complained of back pain. No treatment for his back was given.
B. After several weeks of continuing pain, he presents with leg weakness, which proceeded to paraplegia.
KUMMEL DISEASE
A. Very minimal anterior wedging of the L1 vertebral body is noted by comparing the height of the anterior
body versus the posterior height.
B. A spine film now shows progression of the vertebral body collapse of L1. This almost certainly could have been
avoided with simple bracing of the spine after the initial injury.
DIAGNOSIS ? [FIGURE 42.16]
A. A lateral spine plain film following trauma …
B. Two weeks later, a CT of the spine was performed because of the sudden onset of paralysis.
SPINE FRACTURE IN ANKYLOSING SPONDYLITIS
A. A lateral spine plain film following trauma shows fusion of the spine anteriorly, which was secondary to ankylosing spondylitis. Minimal anterior wedging of the L1 vertebral body is present, which was overlooked.
B. This axial image through L1 shows a fracture of the posterior elements, which was undoubtedly present on the initial visit to the emergency room.
Patients with ankylosing spondylitis need to be examined
closely for any back pain following trauma and imaged with CT or MRI if any pain is present.
IDENTIFY THIS MEASUREMENT ?
(include its anatomic location) [FIGURE 42.64]
BOHLER ANGLE IN A NORMAL CALCANEUS
This drawing depicts the normal calcaneus with a line across the anterior process extending to the apex of the calcaneus intersecting with a line from the posterior portion of the calcaneus to the apex.
This is termed Böhler angle, and when it becomes flattened or less than 20 ° , a calcaneal fracture should be diagnosed.
DIAGNOSIS ? [FIGURE 42.7]
CLAY-SHOVELER RACTURE
A nondisplaced fracture of the C7 spinous process (arrow) is noted, which is diagnostic of a clay-shoveler fracture.
DIAGNOSIS ? [FIGURE 42.58]
The patient’s recent history included an increase in his jogging.
STRESS FRACTURE OF THE TIBIA
A. An irregular focus of sclerosis is seen in the posterior proximal tibia with adjacent periostitis. There was concern that this might represent a primary bone tumor, and the surgeons recommended a biopsy.
B. An MR scan was performed, however, which shows a linear low-signal area running obliquely across the tibia on this T1-weighted coronal image, which is characteristic for a stress fracture. No significant soft tissue mass was found.
A stress fracture was diagnosed on the basis of these images.
DIAGNOSIS ? [FIGURE 42.9]
This patient suffered a hyperflexion injury in an automobile accident and presented to the emergency department with severe neurologic deficits.
FLEXION TEARDROP FRACTURE
A lateral radiograph of the lower cervical spine shows wedging anteriorly of the C7 vertebral body with some displacement of the posterior vertebral line at C7 into the central canal.
A small avulsion fracture off the anterior body is also noted.
DIAGNOSIS [FIGURE 42.60]
FRACTURE OF THE HIP
A. An AP view of the hip was obtained in an elderly man following a fall. It was interpreted as normal, and the patient was dismissed from the emergency department. Two weeks later, the patient returned to the emergency department unable to walk and another radiograph (B) was obtained. It shows a complete fracture through the femoral neck.
In retrospect, the fracture can be faintly seen in (A) and should have been picked up initially.
Fractures of the hip in the elderly can be very difficult to see and should be diligently searched for with additional views
when the clinical setting is appropriate.
DIAGNOSIS ? [FIGURE 42.25]
A RADIOGRAPH OF A FRACTURED HAMATE
A radiograph through the wrist in this patient shows a faint lucency surrounded by sclerosis in the left hamate (arrow), which represents a fracture through the base of the hook of the hamate with moderate reactive sclerosis.
This could not be seen in the plain fi lms, even in retrospect.
DIAGNOSIS ? [FIGURE 42.23]
PERILUNATE DISLOCATION
Although the lunate (L) is normal in relation to the distal radius, the capitate (C) and the remainder of the wrist are dorsally displaced in relation to the lunate.
Compare this radiograph with the drawing in Figure 42.22B.
DIAGNOSIS ? [FIGURE 42.29]
AVASCULAR NECROSIS OF THE NAVICULAR
An AP view of the wrist shows a fracture through the waist of the navicular (arrow). The proximal half of the navicular is slightly sclerotic in relation to the remainder of the carpal bones, which indicates avascular necrosis of the proximal half.
DIAGNOSIS ? [FIGURE 42.6]
This patient presented to the emergency department with pain and decreased motion in the cervical spine
ROTATORY FIXATION OF THE ATLANTOAXIAL JOINT.
A. An AP open-mouth odontoid view shows the space on the left side of the odontoid between the odontoid and the lateral mass of C1 ( arrows ) is wider than the corresponding space on the right side. This is often the result of rotation. Therefore, open-mouth odontoid views with right and left obliquities were obtained.
B. This view shows rotation of the patient’s head to the left, which causes the space on the left side of the odontoid process (arrows) to be wider than that on the right, which is appropriate.
C. This view, however, shows that when the patient turns the head to the right, the space on the right (arrows) does not get wider than the space on the left. This is diagnostic
of rotary fixation of the atlantoaxial joint.
DIAGNOSIS ? [FIGURE 42.42]
POSTERIOR SHOULDER DISLOCATION
Note that the humeral head in this patient is slightly displaced from the glenoid on the AP view. This is termed absence of the crescent sign and is often seen with a posterior dislocation.
Compare this with the normal shoulder in Figure 42.41.
DIAGNOSIS ? [FIGURE 42.65]
CALCANEAL FRACTURE
Böhler angle in this calcaneus is less than 20 ° , which is indicative of a fracture of the calcaneus.
DIAGNOSIS ? [FIGURE 42.20]
GAMEKEEPER’S THUMB
A small avulsion injury on the ulnar aspect of the first metacarpophalangeal joint (arrow) is diagnostic of a gamekeeper’s thumb. This is the insertion site for the ulnar
collateral ligament and usually requires internal fixation.
DIAGNOSIS ? [FIGURE 42.4]
A lateral radiograph (A) and drawing (B) of the upper cervical spine in a patient who suffered trauma to the neck shows the anterior arch of C1 is 8 mm anterior to the odontoid process of C2 (arrows).
C1-C2 DISLOCATION
This is diagnostic of a dislocation of C1 on C2 and indicates rupture of the transverse ligaments that normally
hold these vertebral segments together.
DIAGNOSIS ? [FIGURE 42.8]
HANGMAN FRACTURE
A. Lateral films of a patient with a hangman fracture shows an obvious example of the posterior elements of the CT vertebral body fractured and displaced inferiorly (arrow).
B. This view shows a very subtle fracture through the posterior elements of C2 (arrow) in another patient.
A line drawn through the spinolaminar lines of the posterior elements shows the C2 spinolaminar line to be offset posteriorly in this example.
DIAGNOSIS ? (include the technical error involved) [FIGURE 42.1]
This patient presented to the emergency department after an injury suffered while diving into a shallow swimming pool.
He had neck pain but no neurologic deficits.
a. Initial Radiograph
b. Repeat Radiograph
SHOULDERS OBSCURING C5-C6 DISLOCATION
A. The initial radiograph of the C-spine obtained was interpreted as within normal limits. Only five cervical vertebrae are visible, however, because of high-riding shoulders.
B. A repeat examination with the shoulders lowered reveals a dislocation of C5 on C6. To visualize C7, the shoulders were lowered even further.
The C7 vertebral body must be visualized on every lateral C-spine examination in a trauma setting.
DIAGNOSIS ? [FIGURE 42.61]
OCCULT FRACTURE OF THE HIP
A. An AP plain film in an elderly patient with hip pain after a fall appears normal.
B. A coronal T1-weighted MR was obtained because of the clinical suspicion of a fracture and shows linear low signal in the intertrochanteric region (arrow), confirming the fracture.
NORMAL or ABNORMAL ?
[FIGURE 42.3]
NORMAL C1 AND C2
A lateral radiograph (A) and drawing (B) of the upper cervical spine showing the _normal distance of the anterior arch of C1 **less than 2.5 mm in distance** from the odontoid process (dens) of C2_ (arrows).
DIAGNOSIS ? IDENTIFY THE RADIOGRAPHIC VIEW AS WELL.
[FIGURE 42.43]
TRANSCAPULAR VIEW OF AN ANTERIOR DISLOCATION
This transscapular view of the shoulder is obtained by aiming the x-ray beam parallel to the shoulder blade.
The coracoid process (C) can be seen anteriorly and the spine of the acromion (A) can be seen posteriorly. Both of these structures extend inwardly and meet at the glenoid (G). The humeral head is seen in this example to lie anterior to the glenoid.
DIAGNOSIS ? [FIGURE 42.48]
SACRAL STRESS FRACTURE
A. Faint sclerosis is noted in the left part of the sacrum as compared with the right in this patient complaining of pelvic pain. A radionuclide bone scan showed increased isotope uptake on the left half of the sacrum, and metastatic disease
was postulated.
B. A CT scan through this region that demonstrates a cortical disruption ( arrow ) indicative of a fracture. This is a characteristic plain film and CT appearance of a stress fracture of the sacrum.
DIAGNOSIS ? [FIGURE 42.35]
MONTEGGIA FRACTURE
A blow to the forearm such as with a policeperson’s nightstick can result in a fracture of the ulna (A). Although the head of the radius appears normally placed in (A), the lateral examination shown in (B) reveals the head of the radius to be displaced.
Failure to recognize this abnormality can result in death of
the radial head, with subsequent elbow dysfunction.
This illustrates the importance of always obtaining two views of a bone after trauma.
DIAGNOSIS ? [FIGURE 42.52]
OSTEOARTHRITIS OF THE SYMPHYSIS PUBIS
Sclerosis with erosion is noted at the symphysis in this ultramarathoner complaining of severe pubic pain. This is characteristic of degenerative joint disease (DJD) or osteoarthritis at this site in such an overuse setting. Erosions
are ordinarily not seen in DJD, except in certain joints such as the symphysis pubis, sacroiliac, and the acromioclavicular.
DIAGNOSIS ? [FIGURE 42.26]
CT OF A FRACTURED HOOK OF THE HAMATE
A CT scan through the wrist in this patient shows sclerosis in the left hook of the hamate (arrow), which represents a fracture. Compare this with the opposite hamate. This could not be seen in the plain films, even in retrospect.
DIAGNOSIS ? [FIGURE 42.57]
STRESS FRACTURE OF THE PROXIMAL TIBIA
A. A faint linear sclerotic area (arrow) is seen, which is characteristic for a stress fracture of the proximal tibia.
B. This view shows the result of continued exercise in this patient: a complete fracture of the tibia and the proximal fibula.
DIAGNOSIS ? [FIGURE 42.44]
PSEUDODISLOCATION OF THE SHOULDER
A. An AP view of the shoulder in this patient who had trauma to the shoulder shows the humeral head to be inferiorly placed in relation to the glenoid with absence of the normal crescent sign. A dislocation was suspected.
B. The transscapular lateral film, however, reveals the humeral head to be normally placed over the glenoid.
This is a pseudodislocation owing to a hemarthrosis.
A search for an occult fracture should be made. In this case, a fracture can be seen in (A) (arrow), which caused bleeding into the joint.
DIAGNOSIS ? [FIGURE 42.36]
GALEAZZI FRACTURE
A. A fracture of the distal radius in this patient is seen on the AP view without a defi nite fracture of the ulna.
B. This view shows an obvious dislocation of the distal ulna,
which would almost certainly not be missed clinically.
This has been termed a Galeazzi fracture and is much less common than the Monteggia fractures.
DIAGNOSIS ? [FIGURE 42.32]
COLLES FRACTURE
A fracture of the distal radius with dorsal angulation is noted, which has been termed a Colles fracture.
DIAGNOSIS ? [FIGURE 42.13]
SPONDYLOLISTHESIS
A. A lateral plain film of the lumbar spine shows that the L5 vertebral body is slightly anteriorly offset on the S1 body as noted by the posterior margins (arrows).
B. The drawing illustrates this more clearly.
Because this offset is less than 25% as measured by the length of the S1 end plate, it is termed a grade 1
spondylolisthesis. A grade 2 offset is more than 25% but less than 50% of the length of the S1 end plate.
DIAGNOSIS ? [FIGURE 42.11]
SEATBELT FRACTURE
Hyperfl exion at the waist can cause anterior wedging of the vertebral body in the lower thoracic or upper lumbar region as shown in (A). By itself, although painful, it is somewhat innocuous; however, (B) shows a horizontal fracture through the right transverse process and pedicle (arrow) because of extreme traction during the flexion injury.
When fracture of the posterior elements occurs, this
injury is considered to be unstable and potentially debilitating. Any anterior wedging injury to a vertebral body should have the posterior elements of that level closely inspected.
DIAGNOSIS ? [FIGURE 42.18]
ROLANDO FRACTURE
A comminuted fracture of the base of the thumb that extends into the articular surface is a more serious type of Bennett fracture, which has been termed a Rolando fracture.
DIAGNOSIS ? {FIGURE 42.55]
STRESS FRACTURE OF THE FEMORAL NECK
An area of linear sclerosis (arrows) is seen at the base of the femoral neck in a runner with hip pain. This is diagnostic of a stress fracture of the femur.
DIAGNOSIS ? [FIGURE 42.54]
SACROILIAC OSTEOPHYTES
A. An AP view of the pelvis in this marathoner shows dense sclerosis over both sacroiliac joints.
B. A CT through this area demonstrates dense, bridging osteophytes, characteristic of degenerative joint disease.
DIAGNOSIS ? [FIGURE 42.45]
FRACTURE OF THE GLENOID
A. An AP view of the shoulder demonstrates a faint lucency indicative of a fracture of the glenoid (arrows) with a fragment
of bone seen inferior to the joint.
B. The full extent of the fracture cannot be appreciated
until the CT is examined. On the CT scan, the fracture can be seen to extend fully through the scapula and is seen to be slightly displaced in the articular portion.
DIAGNOSIS ?
IDENTIFY THE CORRESPONDING DIAGNOSTIC SIGN.
[FIGURE 42.49]
SACRAL STRESS FRACTURE
A. A radionuclide bone scan in an osteoporotic patient with pelvic pain shows a classic “Honda sign” seen with bilateral sacral stress fractures.
B. A T1-weighted coronal MR in this patient shows diffuse low signal throughout the sacrum adjacent to the sacroiliac joints bilaterally. This represents edema and hemorrhage in the fractures and corresponds to the bone scan Honda sign.
DIAGNOSES (2) ? [FIGURE 42.31]
TRIQUETRAL FRACTURE and PERILUNATE DISLOCATION
A perilunate or lunate dislocation is present (it is difficult to classify exactly which has occurred because both the lunate and the capitate are out of their normal position).
A small avulsion is seen on the dorsum of the wrist ( arrow ), which is virtually diagnostic of an avulsion off the triquetrum.
It is often associated with a lunate or perilunate dislocation.
DIAGNOSIS ? [FIGURE 42.53]
OSTEOARTHRITIS OF THE SACROILIAC JOINT
DIAGNOSIS ? [FIGURE 42.51]
RECTUS FEMORIS AVULSION
An AP plain film of the left hip shows a faint calcific density superior to the acetabulum (arrow), which is characteristic for an avulsion of the rectus femoris muscle from the anterior inferior iliac spine.
DIAGNOSIS ? [FIGURE 42.14]
ANTERIOR WEDGE COMPRESSION FRACTURE
Anterior compression of this lower T-spine vertebral body (arrow) is present, which may or may not be acute. If the patient has pain in this area, it is most likely acute and must be protected with a back brace until the symptoms abate.
DIAGNOSIS ? [FIGURE 42.38]
DISPLACED ELBOW FAT PADS
A lateral view of the elbow in this child shows a posterior fat pad (arrow) and a sail sign anteriorly ( curved arrow ).
This is indicative of a fracture about the elbow, which in a child (epiphyses are open) usually means a supracondylar fracture.
NORMAL or ABNORMAL [FIGURE 42.21]
NORMAL LATERAL RADIOGRAPH OF THE WRIST
The normal lateral view should show the lunate seated in the distal radius and the capitate seated in the lunate.
A line drawn up through the radius
should connect all three structures. Compare this radiograph with the drawing in Figure 42.22A.
DIAGNOSIS ? DIAGNOSTIC SIGN SHOWN?
[FIGURE 42.27]
ROTATORY SUBLUXATION OF THE NAVICULAR;
TERRY THOMAS SIGN
An AP view of the wrist shows a gap or space between the navicular and the lunate (arrow).
This is abnormal and represents the “Terry Thomas” sign,
which means the scapholunate ligament is ruptured.
This is diagnostic of a rotatory subluxation of the navicular.
DIAGNOSIS ? [FIGURE 42.33]
SMITH FRACTURE
A fracture of the distal radius with volar angulation such as this is called a Smith fracture. This is a much less common injury than the Colles fracture, shown in Figure 42.28 .
DIAGNOSIS ? [FIGURE 42.5]
JEFFERSON FRACTURE
A. An AP open-mouth odontoid view is suspicious for the lateral masses of C1 being laterally displaced on the
body of C2. Because of overlying structures, however, this is difficult to appreciate.
B. A CT examination was obtained and shows multiple fracture sites in the C1 ring (arrows).
This is called a Jefferson fracture. CT should be routinely used in spinal trauma because of frequent shortcomings of plain films.
DIAGNOSIS ? [FIGURE 42.63]
LISFRANC FRACTURE
An AP view of the foot in this patient shows a space between the first and the second metatarsals with the base of the second metatarsal displaced off the second cuneiform.
This is indicative of a Lisfranc fracture dislocation.
DIAGNOSIS ? [FIGURE 42.19]
MALLET FINGER
A small avulsion injury is noted at the base of the distal phalanx, which is where the extensor digitorum tendon inserts. This is termed a mallet finger or baseball fnger because it is often caused by a baseball striking the distal phalanx and causing the avulsion.
NORMAL or ABNORMAL ?
[FIGURE 42.2]
NORMAL LATERAL CERVICAL SPINE
A. Lateral radiograph of a normal cervical spine.
B. Diagrammatic representation of a lateral C-spine showing four parallel lines that should be observed in
every lateral C-spine examination.
Line 1 is the soft tissue line that is closely applied to the posterior border of the airway through the first four or five vertebral body segments and then widens around the laryngeal cartilage and runs parallel to the remainder of the cervical vertebrae.
Line 2 demarcates the anterior border of the cervical vertebral bodies.
Line 3 is the posterior border of the cervical vertebral bodies. Line 4 is drawn by connecting the junction of the lamina at the spinous process, which is called the spinolaminar
line. It represents the posterior extent of the central canal that contains the spinal cord itself.
Theselines should be generally smooth and parallel with no abrupt step-offs.
DIAGNOSIS ? [FIGURE42.12]
A. An oblique plain film of the lumbar spine shows a defect in the ________ ( arrow ), which is diagnostic of a _______.
NECK OF THE “SCOTTIE DOG” AT L5;
SPONDYLOLYSIS
B. A drawing of an oblique view of the lumbar spine shows
how a spondylolysis appears as a “collar” around the Scottie dog’s neck.
DIAGNOSIS ? [FIGURE 42.62]
TIBIAL PLATEAU FRACTURE
A. A cross-table lateral plain film of the knee reveals a fat–fluid level (arrows), which indicates a fracture with fatty marrow leaking into the joint.
B. An AP view shows a barely discernible fracture (arrow) near the tibial spines, indicative of a tibial plateau fracture.
IDENTIFY THIS NORMAL RADIOGRAPHIC FINDING.
[FIGURE 42.39]
NORMAL ANTERIOR FAT PAD OF THE ELBOW
Note the lucency just anterior to the humerus of this normal elbow and compare this with the sail sign of the anterior fat pads in Figures 43.33 and 43.34.
DIAGNOSIS ? [FIGURE 42.59]
CALCANEAL STRESS FRACTURE
A linear band of sclerosis is seen in the posterior calcaneus (arrows), which is diagnostic for a stress fracture of the calcaneus.
DIAGNOSIS ? [FIGURE 42.34]
PLASTIC BOWING DEFORMITY OF THE FOREARM
These AP and lateral views of the forearm of a child show the radius to be abnormally bowed anteriorly. This has been termed a plastic bowing deformity of the forearm and occurs only in children.
