Trauma - Pelvis/Acetabulum (Complete) Flashcards
1
Q
What is the clinical evaluation of a pelvic fracture?
[CORR trauma]
A
- ATLS
- Observation
- Open
- Blood at the meatus
- Morell-Lavalle
- Pelvis stability
- LLD
- Rectal exam
- Blood
- Tone
- High riding prostate
- Distal NV exam
2
Q
When and how is a retrograde urethrogram performed?
A
- Insert foley catheter ~2cm into urethra
- Inflate balloon ~2-3mL of water
- Stretch penis to straighten and hold glans to maintain catheter in place
- Inject 20-30mL of water soluble contrast dye taking an xray after each 10mL
- If demonstrates intact urethra the balloon is deflated then advanced into the bladder and reinflated
- To perform cystogram:
- Inject 300mL of diluted contrast dye (1:1 with saline)
- Clamp the catheter and obtain xray
- Drain the bladder completely and repeat xray
- Alternative to bedside cystogram is a CT cystogram
- Does not require draining bladder
- Abnormal retrograde urethrogram
- Extravasation or urethral occlusion
- Consult urology
- Abnormal cystogram
- Extravasation
- Intraperitoneal extravasation
- Requires surgery
- Extraperitoneal extravasation
- Requires bladder decompression with foley
- Intraperitoneal extravasation
3
Q
In cases of open pelvis fractures, what additional surgical procedure needs to be considered?
[Rockwood and Green 8th ed. 2015]
A
Diverting colostomy – 50% death rate if not done
4
Q
What are the recommended routine radiographs for a pelvis fracture?
[J Orthop Trauma 2014;28:48–56]
A
- AP pelvis
- Inlet
- Outlet views
5
Q
How do you obtain an inlet and outlet view?
[J Orthop Trauma 2014;28:48–56]
A
- Traditionally:
- Inlet - 45 degree caudal tilt
- Outlet - 45 degree cranial tilt
- Current recommendation:
- Inlet - 25 caudal tilt
- Outlet - 60 degree cranial tilt
6
Q
What are the options for external fixation for pelvis fractures and how do you insert the pins?
[J Orthop Trauma 2014;28:48–56]
A
- Iliac crest/wing external fixation pins
* Start point- 3-4cm posterior to the ASIS centred between the inner and outer tables
* Fluoro image used: - Obturator outlet view
* Pin direction - Superior to inferior directed towards the supraacetabular bone
- 3-4cm posterior to the ASIS centred between the inner and outer tables
- Supraacetabular external fixation pins
- Start point
- Center of the teardrop visualized on obturator outlet view
- At least 2cm above superior acetabulum
- Fluoro image used:
- Obturator outlet view for start point
- And for visualization of pin along its entire length between inner and outer tables
- Iliac oblique view for depth and to ensure ~1-2cm above sciatic notch
- OO (start)–>IO (length/location)–>OO (trajectory)
- Obturator outlet view for start point
- Pin direction
- AIIS to PIIS
7
Q
What are the advantages and disadvantages of supraacetabular ex-fix pins (Hannover technique)?
[Rockwood and Green 8th ed. 2015]
A
Advantages
- Pins are out of the way of abdominal procedures
- Two pins are sufficient (one on either side)
- Fixation is excellent
- Allows for direction of closure of open book injury in the same plane
- Biomechanically superior in resisting rotational forces and equal control of flexion/extension forces compared to iliac crest pins
Disadvantages
- More dependent on fluoro
8
Q
How do you classify pelvic fractures?
[JAAOS 2013;21:448-457]
A
- Young-Burgess Classification
- Lateral compression (LC)
- LC-I
- Pubic rami fracture + sacral ala buckle fracture
- LC-II
- Pubic rami fracture + crescent fracture
- LC-III
- Windswept pelvis
- ***NOTE: pubic rami fracture is horizontal
- LC-I
- Anterior-Posterior compression (APC)
- APC-I
- Widening of the pubic symphysis <2.5cm
- APC-II
- Widening of the pubic symphysis >2.5cm + widening of anterior SI
- Posterior SI remains aligned
- Widening of the pubic symphysis >2.5cm + widening of anterior SI
- APC-III
- Complete disruption of the posterior pelvis
- Anterior and posterior SI joint disruption OR nonimpacted posterior fracture
- Complete disruption of the posterior pelvis
- APC-I
- Vertical shear (VS)
- Vertical displacement of a hemipelvis with complete disruption of the SI ligaments or a fracture through the sacrum or ilium
- Combined
2. Tile classification [Rockwood and Green 8th ed. 2015] - Type A – Pelvic Ring Stable
- A1
- Fractures not involving the ring
- Eg. avulsion, iliac wing or crest fractures
- Fractures not involving the ring
- A2
- Stable minimally displaced fractures of the pelvic ring
- A1
- Type B – Pelvic Ring Rotationally Unstable, Vertically Stable
- B1
- Open book
- B2
- Lateral compression, ipsilateral
- B3
- Lateral compression, contralateral, or bucket handle-type injury
- B1
- Type C – Pelvic Ring Rotationally Unstable and Vertically Unstable
- C1 = unilateral
- C2 = bilateral
- C3 = associated acetabular fracture
9
Q
What radiographic feature has been described as a ‘sentinel sign’ of a vertical shear injury?
[Rockwood and Green 8th ed. 2015]
A
L5 transverse process fracture
10
Q
What is considered pathognomonic radiographic feature for lateral compression injuries?
[Rockwood and Green 8th ed. 2015]
A
Rami fractures in the transverse plane on the inlet view
11
Q
In a hypotensive patient with a pelvic ring fracture and no other sources of hemorrhage, what options should be considered to control the bleeding?
[Rockwood and Green 8th ed. 2015]
A
- Stabilization of unstable pelvic ring fractures
- Traction
- Pelvic binder
- External fixation
- Military antishock trousers
- Angiographic embolization
* Consider when contrast extravasation evident on CT - Retroperitoneal pelvic packing
12
Q
What vessels are most commonly involved in arterial bleeds associated with pelvic ring fractures?
[Rockwood and Green 8th ed. 2015]
A
Branches of the internal iliac
- Superior gluteal artery
- Lateral sacral
- Internal pudendal
- Inferior gluteal
- Obturator artery
13
Q
What are indications for nonoperative management of pelvic ring fractures?
[Rockwood and Green 8th ed. 2015]
A
- Stable pelvic ring fractures
- Stable sacral fractures
- Comorbidities precluding surgery
- Poor bone quality where screw purchase may be problematic
- Low-energy osteoporotic pelvic ring fracture
14
Q
What are indications for anterior pelvis ring stabilization?
[Rockwood and Green 8th ed. 2015]
A
- >2.5cm of symphysis diastasis on either static or dynamic (EUA) imaging
- Augment posterior fixation in VS fractures
- Augmentation of posterior fixation in completely unstable pelvic fractures
- Augmentation of posterior fixation in osteopenic bone
- Significantly displaced rami fractures
- Locked symphysis
- Straddle fractures
- Pain and inability to mobilize (relative)
15
Q
What are relative indications for posterior pelvic ring stabilization?
A
- Complete disruption of the SI joint
* Anterior and posterior SI ligaments - Vertical displacement
- Displaced crescent fractures
* Iliac wing fractures that enter and exit both crest and greater sciatic notch or SI joint - Displaced sacral fracture
- Complete sacral fractures with potential for displacement
- Lumbopelvic disassociation
16
Q
What is the mainstay of anterior approaches for internal fixation of the pelvis?
[Rockwood and Green 8th ed. 2015]
A
Pfannenstiel incision
- Transverse incision 2cm above pubic symphysis
- Length is from one external inguinal canal to the other
- Allows identification and protection of spermatic cord/round ligament
- Linea alba is then split longitudinally
- Symphysis and pubic bodies are exposed
- Carefully separate the bladder from the posterior pubis and protect with a large malleable retractor
17
Q
What are indications for surgical fixation of pubic rami fractures?
[Rockwood and Green 8th ed. 2015]
A
- Rami fractures associated with vertical shear injury
- Augmentation of posterior fixation when there is considerable instability
18
Q
What are the surgical options for pubic rami fractures?
A
- Pelvic reconstruction plates
- Ex-fix
- Antegrade or retrograde percutaneous screw fixation
19
Q
When should an antegrade screw be chosen over a retrograde screw for fixation of pubic rami fractures?
[Rockwood and Green 8th ed. 2015]
A
- When the fracture is:
- Lateral, near the pubic root
- In the middle of the ramus
- If the patient is morbidly obese
***Retrograde screws are for medially based fractures
20
Q
What structures are at risk when placing a percutaneous screw for pubic rami fixation?
[Rockwood and Green 8th ed. 2015]
A
- External iliac vessels (superior)
- Acetabulum (inferior)
- Bladder (deep)
- Corona mortis (deep)
21
Q
What are the important technical points for antegrade percutaneous screw fixation for pubic rami fractures?
[Rockwood and Green 8th ed. 2015]
A
- Screw type
* Cannulated partially threaded 6.5 or 7.3mm screw - Start point
* Midpoint on a line drawn between the tip of the GT and a spot about 4cm posterior to ASIS - Fluoro views used
* Obturator outlet view and inlet view to confirm within bone
22
Q
What are the important technical points for retrograde percutaneous screw fixation for pubic rami fractures?
[Rockwood and Green 8th ed. 2015]
A
- Screw type
- 3.5 or 4.5 screw in AO lag screw fashion
- Or 6.5 or 7.3mm cannulated partially threaded screw
- Start point
* Incision made over contralateral pubic tubercle with blunt dissection towards ipsilateral pubic tubercle - Fluoro views used
* Obturator outlet view and inlet view to confirm within bone
23
Q
How are LC-2 crescent fractures subclassified and what are the surgical options?
[Rockwood and Green 8th ed. 2015]
A
SI joint is divided into thirds (Day classification)
- Type I
- Anterior third
- Pelvic recon plates and lag screws
- Anterior approach
- Or LC-II screw
- Same path as supraacetabular ex-fix pin
- Type II
- Middle third
- Lag screws from PIIS directed toward sciatic buttress +/- recon plate for neutralization
- Posterior approach
- Type III
- Posterior third
- Lag screw (posterior approach) and SI screw
***Note = the crescent fragment is considered the ‘constant fragment’ and the ilium should be reduced to it
24
Q
Successful closed reduction of an SI joint dislocation is required for percutaneous SI screw placement, what techniques can be used to obtain the closed reduction?
[Rockwood and Green 8th ed. 2015]
A
- IRTOTLE technique
* Internal rotation and taping of the lower extremities - Sheet wrapped at level of GTs
- Sheet wrapped around pelvis with holes cut for screw placement
25
What radiographic views are used to place an SI screw?
[Rockwood and Green 8th ed. 2015]
1. Inlet view – AP screw position
2. Outlet view – superior/inferior screw position
3. Lateral sacral view (optional) useful to determine start point
26
What are the technical points of achieving a true inlet and outlet pelvis view?
[JBJS REVIEWS 2018;6(1):e7]
1. Inlet view
* Superimposition of the anterior S1 and S2 alar opacities
2. Outlet view
* Superior portion of the pubic body and rami should be superimposed over the S2 sacral foramina
27
What are the radiographic landmarks on a lateral sacral view?
[Rockwood and Green 8th ed. 2015]
1. Iliac cortical density (sacral ala)
* The entry point should be:
* Anterior in S1
* Inferior to the iliac cortical density (ICD)
* Parallels the sacral alar slope, usually slightly caudal and posterior
* Marks the anterosuperior boundary of the safe zone for an iliosacral screw which may injure the L5 nerve root if it penetrates this cortex. [AOfoundation]
2. Sacral promontory
3. Anterior aspect of the sacral canal
4. Vestigial S1-S2 disc space
* Corresponds to S1 foramen
28
What are the important technical points for percutaneous SI screw placement?
[Rockwood and Green 8th ed. 2015]
1. A 6.5, 7.3 or 8.0mm partially threaded cannulated screw is used with washer
2. The screw is placed perpendicular to the SI joint
3. The start point for the guidewire is confirmed on inlet, outlet and lateral sacral (optional) views
4. Guidewire is advanced alternating between inlet and outlet views
* Ensuring on inlet view that it is anterior to the sacral canal and posterior to the sacral promontory
* Ensuring on outlet view that it is above the S1 foramen and below the superior endplate of S1
5. Depth of guidewire is just adjacent or lateral to the opposite S1 sacral foramen on the outlet view
6. After screw is placed, position is confirmed on standard AP pelvis, inlet and outlet views to confirm proper placement of screw in the S1 corridor
29
What are the features of sacral dysmorphism?
[Rockwood and Green 8th ed. 2015]
1. Upper sacrum being collinear with the iliac crest (normally below)
2. Presence of mammilary processes in the alar region
3. Uppermost sacral foramina are larger, misshapen and irregular (i.e. oval, not circular)
4. Residual disc space between S1 and S2
5. Alar slope is more acute on lateral sacral view
* i.e. Not collinear with iliac cortical density
6. Tongue-in-groove SI articulation seen on CT
7. Anterior cortical indentation is present in the dysmorphic sacral ala
NOTE: sacral dysmorphism present in up to 44% of population
30
How does sacral dysmorphism change SI screw placement?
[Rockwood and Green 8th ed. 2015]
1. Screw must be placed obliquely in cephalad direction into S1
2. Prevents through-and-through transiliac fixation
3. S2 may be used instead of S1 for iliosacral or transiliac screw
31
How does the fracture pattern affect planning for SI screws?
1. Sacral fractures
* Longer screws that traverse the spinopelvic region preferred
2. Pure SI joint instability
* Shorter screws
3. Comminuted sacral fractures
* Avoid compression of the neural foramen
* Consider fully threaded screw
4. Simple sacral fractures
* Partially threaded screws
5. Vertically unstable, comminuted fractures
* SI screws alone do not provide adequate fixation
32
What forms the anterior column and posterior column?
[Rockwood and Green 8th ed. 2015]
Anterior column
* Anterior half of the iliac wing
* Adjacent pelvic brim
* Anterior half of the acetabular articular surface
* Including anterior wall
* Superior pubic ramus
Posterior column
* Begins at the superior aspect of the greater sciatic notch
* Includes the bone adjacent to the greater and lesser sciatic notches
* Posterior half of the acetabular articular surface
* Including posterior wall
* Ischial tuberosity
\*\*\*Note: the columns are connected at the inferior aspect by the ischiopubic ramus and medially at the quadrilateral plate
* Sciatic buttress is what links the two columns to the SI articulation
33
What are the recommended routine radiographs for an acetabulum fracture?
[Instr Course Lec 2015; 64-139]
1. AP pelvis
2. Judet views
* Obturator oblique and iliac oblique views
34
What are the 6 acetabular landmarks seen on an AP radiograph?
[Instr Course Lec 2015; 64-139]
1. Ilioischial line
2. Iliopectineal line
3. Anterior rim
4. Posterior rim
5. Roof
6. Teardrop
35
Describe the Letournel Classification of acetabular fractures
[Rockwood and Green 8th ed. 2015]
1. Elementary fracture patterns (5)
* Posterior wall
* Posterior column
* Anterior wall
* Anterior column
* Transverse
2. Associated fracture patterns (5)
* Posterior column and posterior wall
* Transverse and posterior wall
* Anterior column (or wall) and posterior hemitransverse
* T-shaped
* Both column
36
Based on radiographs alone how do you determine which acetabular fracture pattern exists?
[JAAOS 2018;26:83-93]
1. Both ilioischial and iliopectineal lines disrupted
* Obturator ring intact
* Posterior wall fracture seen on the obturator oblique view
* = Transverse and posterior wall
* Posterior wall fracture not seen on the obturator oblique view
* = Transverse fracture
* Obturator ring not intact
* Fracture does not involve ilium
* = T-type fracture
* Fracture does involve the ilium
* Spur sign seen on obturator oblique view
* = Associated both column
* Spur sign not seen on obturator oblique view
* = Anterior column posterior hemitransverse
2. Only Iliopectineal line disrupted = anterior column
3. Only Ilioischial line disrupted
* Posterior wall fracture seen on the obturator oblique view
* = Posterior column and posterior wall
* Posterior wall fracture not seen on the obturator oblique view
* = Posterior column fracture
4. Both ilioischial and iliopectineal lines intact
* Fracture seen on the obturator oblique view
* = Posterior wall fracture
* Fracture seen on the iliac oblique view
* = Anterior wall fracture
\*\*\*\*\*Liew 2-Column Algorithm (Based on AP Pelvis)
Is dome attached to ilium?
* No = ABC
* Yes = Is obturator ring Intact?
* Yes = Transverse
* No = Is Anterior column segmental?
* Yes = Ant Column + Post Hemi-transverse
* No = T-Type
37
How do you differentiate an anterior wall from an anterior column fracture on radiographs?
[Rockwood and Green 8th ed. 2015]
1. Anterior wall has 2 breaks in the iliopectineal line
* Anterior column has 1 or none
2. Anterior column has a break in the ischiopubic ramus
* Anterior wall does not
38
What are the 3 classifications of anterior column fractures?
[Rockwood and Green 8th ed. 2015]
1. High = fracture exits iliac crest
2. Intermediate = fracture exits ASIS
3. Low = fracture exits below AIIS
39
What are the 3 types of transverse acetabular fractures ?
[Rockwood and Green 8th ed. 2015]
1. Transtectal
* Cross the weightbearing dome of the acetabulum
* More vertical fracture compared to infratectal and has less articular surface remaining
2. Juxtatectal
* Cross the articular surface at the level of the top of the cotyloid fossa
3. Infratectal
* Cross the cotyloid fossa
40
What is the ‘gull wing sign’ in acetabular fractures?
[Rockwood and Green 8th ed. 2015]
Impaction of the medial acetabulum roof
* Occurs with anterior and posterior hemitransverse or isolated anterior column fractures
* Presence of this impaction is a poor prognostic sign
\*\*\*Easily confused with "Gull sign"
* Initially described Letournel and Judet for variations of posterior column fractures where the posterior column displaces and takes the hind portion of acetabular roof
* Therefore the posterior segment loses its normal relationship with the segment still attached to anterior column and forms “an image like a gull in flight”
41
The ‘spur sign’ is pathognomonic for what fracture type?
[Rockwood and Green 8th ed. 2015]
Associated both column
* Best seen on the obturator oblique view
* Represents the intact iliac fragment
* Represents the external cortex of the most caudal portion of the intact ilium
42
How much fracture displacement involving the superior acetabular dome (WB surface) is acceptable to consider nonoperative management?
[Rockwood and Green 8th ed. 2015]
\<2mm
43
What are the ‘roof arc measurements’ described be Matta and what are their significance?
[Rockwood and Green 8th ed. 2015]
1. A vertical line is drawn through the centre of the femoral head
* Second line is drawn from the centre of the femoral head to the fracture location on the acetabular articular surface
2. The measurement is made on 3 views
* Medial roof arc measured on AP
* Anterior roof arc measured on obturator oblique
* Posterior roof arc measured on iliac oblique
3. Significance
* Determines if the intact acetabulum is sufficient to maintain a stable and congruous relationship with the femoral head
4. Nonoperative treatment indicated if: [Vrahas et al JBJS 1999]
* Medial RAM \> 45°
* Anterior RAM \> 25°
* Posterior RAM \> 70°
* \*\*\*Initial cutoff was 45 for medial, anterior and posterior
\*\*\* NOTE: not applicable to both column and posterior wall fractures
44
What is ‘secondary congruence’ in both column fractures?
[Rockwood and Green 8th ed. 2015]
1. Describes congruency between the femoral head and the displaced acetabular articular surface without skeletal traction applied
* Parallelism between femoral head and acetabular articular surface must be seen on all three views
2. If present can treat nonop
* Unless hip motion will be limited or limb will be unacceptably shortened
45
What do CT scans allow better visualization of compared to radiographs in context of acetabulum fractures?
[JAAOS 2018;26:83-93]
1. Intra-articular fracture fragments
2. Marginal impaction
3. Articular incongruity
4. Associated femoral head fractures
46
On an axial CT slice through the articular surface what orientation of fracture line coincides with what fracture pattern?
[JAAOS 2018;26:83-93]
1. Horizontal (coronal) = column-type fracture
2. Vertical (sagittal) = transverse-type
47
What are indications for emergency acetabular fixation?
[Rockwood and Green 8th ed. 2015]
1. Recurrent hip dislocation following reduction despite traction
2. Irreducible hip dislocation
3. Ipsilateral femoral neck fracture
4. Progressive sciatic nerve deficit following fracture or closed reduction
5. Associated vascular injury requiring repair
6. Open fractures
48
What are general surgical indications for acetabular fractures?
[Miller’s, 6th ed.] [AAOS comprehensive review 2, 2014]
1. Displaced fractures with \>2mm gap at articular surface
2. Intra-articular fracture fragments
3. Marginal impaction
4. Hip instability
49
What are nonoperative indications for acetabular fractures?
[Miller’s, 6th ed.]
1. Nondisplaced or minimally displaced fractures (\<2mm)
2. Roof arc angle \>45 (medial), \>25 (anterior), \>70 (posterior)
3. Posterior wall fractures stable on dynamic stress test and without marginal impaction
4. Fracture of both columns with secondary congruence
5. Severe comminution in elderly patient in whom THA is planned after fracture healing
50
What are the common surgical approaches used in acetabular surgery?
1. Ilioinguinal
2. Modified Stoppa
3. Iliofemoral
4. Kocher-Langenbeck
5. Extended iliofemoral
51
What are the 3 windows of the ilioinguinal approach and what do they allow access to?
[Rockwood and Green 8th ed. 2015]
1. Lateral window
* Lateral to the iliacus muscle
* Exposes:
* Iliac crest
* Internal iliac fossa as far medial as the SI joint and as far distal to the pelvic brim
2. Middle window
* Iliopsoas and femoral nerve lateral and external iliac artery and vein medial (iliopectineal fascia)
* Exposes:
* Anterior wall
* Pectineal eminence
* Pelvic brim
* Quadrilateral surface
3. Medial window
* External iliac vessels lateral and spermatic cord/round ligament taken either medial or lateral
* Exposes:
* Superior pubic ramus
* Pubic symphysis
52
What are the lacuna vasorum and lacuna musculorum with respect to the ilioinguinal approach?
[JAAOS 2015;23:592-603]
1. Lacuna vasorum
* = Femoral vessels and lymphatics in a common sheath
2. Lacuna musculorum
* = Iliopsoas and femoral nerve
3. Iliopectineal fascia lies between and must be divided to the level of the pectineal eminence to create the 3 windows
53
What fractures are suitable for ilioinguinal approach?
[JAAOS 2015;23:592-603]
1. Anterior column and/or the anterior wall
2. Anterior column-posterior hemitransverse fractures
3. Many both-column and transverse fractures.
54
What does the modified Stoppa approach allow better visualization of compared to the ilioinguinal approach?
[JAAOS 2015;23:592-603]
Quadrilateral plate
55
What fractures are suitable for Kocher-Langenbeck approach?
[JAAOS 2015;23:592-603]
1. Posterior column and posterior wall
2. Many transverse and T-type fractures
56
Which artery is at risk during the Kocher-Langenbeck approach and how do you protect it?
[JAAOS 2015;23:592-603]
Deep branch of the medial femoral circumflex artery
* Main blood supply to the femoral head
* Piriformis and conjoint tenotomy performed 1.5cm from their insertion
* Preserve the quadratus femoris insertion
* Obturator externus and dbMFCA lie immediately anterior to it
* Preserve the obturator externus tendon
57
What fractures are suitable for Extended Iliofemoral approach?
[JAAOS 2015;23:592-603]
1. Complex both column fractures
2. Acetabular fractures that are treated subacutely (\>3 weeks)
58
What factors have been associated with postoperative infection following acetabular ORIF?
[JAAOS 2015;23:592-603]
1. Elevated BMI
2. ICU stay
3. Morel-Lavallee
4. Preoperative embolization
5. Preoperative leukocytosis
59
What is the rate of HO following the EIF, K-L and ilioinguinal approaches?
[JAAOS 2015;23:592-603]
1. EIF = 35%
2. Kocher-Langenbeck = 10%
3. Ilioinguinal = 2%
60
What is the most common iatrogenic nerve injury during acetabular surgery?
[JAAOS 2015;23:592-603]
Peroneal division of the sciatic nerve
61
What are features of acetabular fractures in the elderly compared to younger patients?
[JAAOS 2017;25:577-585]
1. Low-energy mechanisms
2. Anterior column
3. Medialization of the femoral head
4. Disruption of the quadrilateral plate
5. Impaction of the posteromedial dome
6. When posterior wall involved there is:
* More comminution
* More severe marginal impaction
* More likely associated with posterior hip dislocation
62
What are the treatment options for acetabular fractures in the elderly?
[JAAOS 2017;25:577-585]
1. Nonoperative
2. Percutaneous fixation
* Reserved for anterior or posterior column fractures and large osseous corridors
3. ORIF
4. Delayed THA
5. Acute THA
* Indicated if:
* Marked pre-existing OA
* Fracture pattern prone to early failure or post-traumatic OA
* Goal is restoration of the acetabular columns to provide stability for implantation of a press-fit acetabular implant
63
What are negative predictors of hip survival after acetabular ORIF?
[JAAOS 2017;25:577-585]
1. Age \>40
2. Nonanatomic reduction
3. Hip dislocation
4. Acetabular roof or posterior wall involvement
5. Femoral head involvement
6. Initial displacement ≥20mm
64
What are 4 radiographic features of an associated posterior hip dislocation on the AP view?
[Instr Course Lec 2015; 64-139]
1. Break in Shenton line
2. Proximal migration of the lesser trochanter
3. Relatively smaller appearing head compared to contralateral side
4. Bony double density above femoral head
* Posterior wall fragment atop the femoral head
65
What additional information does a CT scan (with slices 3mm or less) provide in a posterior hip dislocation/wall fracture?
[Instr Course Lec 2015; 64-139]
1. Intra-articular bony or osteochondral fragments
2. Size of the posterior wall fragment
3. Location of the posterior wall fragment
4. Number of fragments
5. Marginal impaction of articular surface
6. Fractures of femoral head
66
What are indications for nonoperatively managed posterior wall fractures?
[Instr Course Lec 2015; 64-139]
Stable, concentrically reduced
67
How do you assess for instability of posterior wall fractures?
[Instr Course Lec 2015; 64-139]
1. Posterior wall fracture as shown on CT to involve 50% or more of the joint surface can be assumed to be unstable
2. Dynamic fluoroscopic stress test under GA
* Hip is slowly flexed past 90 degrees while applying longitudinal force to femur
* Visualized once on AP and once on obturator oblique views
* Repeat with hip internal rotated 20 degrees and adducted 20 degrees
* Posterior subluxation indicates instability
* Frank dislocation is not required nor desirable
68
What are indications for emergent surgery in the presence of a posterior wall acetabular fracture?
[Instr Course Lec 2015; 64-139]
1. Irreducible hip dislocation
2. Hip dislocation after reduction that is unstable with traction
3. Posterior wall fracture with an associated femoral neck fracture
4. Open posterior wall fracture
69
What surgical approaches can be used to address posterior wall fractures?
[Instr Course Lec 2015; 64-139]
1. Kocher-Langenbach
2. Kocher-Langenbach with a Ganz trochanteric flip osteotomy
3. Modified Gibson approach
70
What fixation construct is commonly used for a posterior wall fracture?
[Instr Course Lec 2015; 64-139]
Lag screw and buttress plate
* Buttress plate spans the posterior wall fragment from ischium to ilium
* Plate should be slightly undercontoured, placed parallel and close to the acetabular rim
* Minimum of 2 screws above and below
71
What injuries are associated with posterior wall acetabulum fractures?
[Instr Course Lec 2015; 64-139]
1. Knee ligaments
2. Patella fracture
3. Femoral shaft, neck and head fracture
4. Morel-Lavallee lesion
5. Superior gluteal artery
6. Sciatic nerve
72
What are early and late complications associated with posterior wall fractures?
[Instr Course Lec 2015; 64-139]
1. Early
* Iatrogenic nerve injury
* Deep infection
* Intra-articular screw penetration
* Malreduction
* VTE
2. Late
* HO
* Femoral head AVN
* Posttraumatic OA
73
What hip position favours pure posterior hip dislocation?
[Rockwood and Green 8th ed. 2015]
Increased hip flexion, internal rotation and adduction
* Lesser degrees result in fracture-dislocations
74
What hip position results in anterior hip dislocation?
[Rockwood and Green 8th ed. 2015]
Hyperabduction, extension, external rotation
75
What anatomic variation of the proximal femur predisposes to posterior hip dislocation?
[JAAOS 2007;15:716-727]
Decreased femoral head anteversion
76
What are contra-indications to closed reduction of a hip dislocation?
[Rockwood and Green 8th ed. 2015]
1. Nondisplaced femoral neck fracture
* Percutaneous screw fixation prior to closed reduction
2. Other injuries that would preclude using the lower limb to manipulate the hip
NOTE: closed reduction should be attempted with concomitant femoral head or acetabular fractures
77
What is the technique for closed reduction of a posterior hip dislocation?
[Rockwood and Green 8th ed. 2015]
Allis maneuver
* Countertraction applied to ASIS
* Knee and hip flexed
* Inline traction applied to femur with hip in adduction and internal rotation
* Gentle rotation applied until reduced
* Post reduction the hip is extended and externally rotated
* Knee immobilizer applied
78
Prior to reduction of a posterior hip dislocation, what imaging is recommended?
[Rockwood and Green 8th ed. 2015]
AP pelvis
* Unless concern regarding femoral neck fracture or femur, knee or tibia injury that may affect reduction
79
Post reduction of a posterior hip dislocation, what imaging is recommended?
[Rockwood and Green 8th ed. 2015]
1. 5 views of the pelvis (AP, Judet, inlet and outlet)
2. CT scan with 2mm slices
\*\*\*Need XR and CT
80
What is the purpose of obtaining a post-reduction CT scan after reduction of a posterior hip dislocation?
[Rockwood and Green 8th ed. 2015]
1. More sensitive at detecting:
* Small intra-articular fragments
* Femoral head impaction
* Acetabular fractures
* Joint congruity
2. Pre-operative planning in cases of concomitant fracture, irreducible dislocation, or incongruent reduction
81
What structures can result in an irreducible hip dislocation?
[Rockwood and Green 8th ed. 2015]
1. Posterior dislocation
* Piriformis tendon
* Gluteus maximus
* Capsule
* Ligamentum teres
* Posterior wall
* Bony fragment
* Iliofemoral ligament
* Labrum
2. Anterior dislocation
* Capsule
* Rectus femoris
* Labrum
* Psoas tendon
82
What are the indications for open reduction (with or without debridement) for hip dislocations?
[Rockwood and Green 8th ed. 2015]
1. Irreducible dislocations
2. Sciatic nerve injury caused by a reduction attempt
3. Incongruent reduction
* Due to:
* Incarcerated bony fragments
* Soft tissue interposition
* Pipkin type I or II femoral head fracture
83
What are the indications for ORIF following hip dislocations?
[Rockwood and Green 8th ed. 2015]
1. Posterior wall fractures (with instability or incongruent joint)
2. Femoral neck fractures
* If nondisplaced – fix femoral neck fracture prior to reduction
* If displaced – reduce femoral head into acetabulum then fix femoral neck
* In elderly – consider hemiarthroplasty or THA
3. Femoral head fractures
* Pipkin I with \>1mm displacement and large fragment
* Smaller fragments excised if causing incongruent joint
* Pipkin II with \>1mm displacement
4. Femoral head impaction fracture \>2cm2
* Consider elevation and grafting
84
What percent of posterior hip dislocations have an associated femoral head fracture?
[JAAOS 2007;15:716-727]
5-15%
85
What is the Pipkin Classification for femoral head fractures?
[Rockwood and Green 8th ed. 2015]
Type I – Below the fovea
Type II – Above the fovea
Type III – Femoral head fracture with associated femoral neck fracture
Type IV – Femoral head fracture with associated acetabular fracture
86
Where is the typical fragment located on the femoral head?
[Rockwood and Green 8th ed. 2015]
Anteromedial
* Sheared off as the femoral head impinges the posterior wall with the hip in an internally rotated position
87
What is the initial emergency department management of a femoral head fracture with an associated hip dislocation?
[JAAOS 2007;15:716-727]
1. Emergent closed reduction
* Associated femoral neck fracture (Pipkin 3) is a contraindication to closed reduction
2. Post reduction xrays and CT are obtained
88
What are the indications for emergent open reduction in the presence of a femoral head fracture?
[JAAOS 2007;15:716-727]
1. Irreducible fracture dislocation
2. Associated femoral neck fracture (Pipkin 3)
NOTE: CT scan should be performed prior to OR if it will not significantly delay surgery
89
What are the indications for nonsurgical management of femoral head fractures?
[JAAOS 2007;15:716-727]
Pipkin I that meets the following criteria:
* Near-anatomic reduction (\<2mm displacement)
* Stable hip
* No interposed fragments preventing congruent joint
90
What are the indications for surgery in femoral head fractures?
[JAAOS 2007;15:716-727]
1. Non-anatomic reduction of femoral head
2. Unstable hip joint
3. Intra-articular fragments preventing congruent hip joint
91
What is the preferred surgical approach to perform femoral head ORIF?
[Rockwood and Green 8th ed. 2015]
Anterior approach
* Allows direct visualization of fragment without redislocation
* Preserves posterior femoral head blood supply
92
How is the femoral head fracture fixed from an anterior approach?
[JAAOS 2007;15:716-727]
1. The hip is not redislocated
2. Fracture fragment is brought into view with hip external rotation, extension and slight abduction
3. Fixation with A-P lag screws (3.5 or 2.7mm), headless screws (Herbert, Acutrak), or bioabsorbable pins
93
What are the indications for posterior approach to the hip for femoral head fractures?
[JAAOS 2007;15:716-727]
1. Irreducible hip dislocations
2. Posterior acetabular wall requiring ORIF
94
How is the femoral head fracture fixed from a posterior approach?
[JAAOS 2007;15:716-727]
1. Must be fixed prior to reduction of hip dislocation
* Fixed with P-A interfragmentary lag screws
2. Alternative
* Surgical hip dislocation
95
What are the indications for femoral head fracture fragment excision?
[JAAOS 2007;15:716-727]
1. Small or comminuted fragments
2. Fragments not involving weightbearing portion
96
What is the management of Pipkin III fractures?
[JAAOS 2007;15:716-727]
1. Fixation of femoral neck fracture first via lateral or anterolateral approach
2. Femoral head fracture managed based on displacement
* Minimally displaced can be managed nonoperatively
* Displaced managed with ORIF through separate anterior approach
3. Rockwood recommends:
* Nondisplaced femoral neck
* CRPP from lateral approach
* Anterior approach if needed for femoral head
* Displaced femoral neck
* Surgical hip dislocation
97
What is the management of Pipkin IV fractures?
[JAAOS 2007;15:716-727]
Approach determined by type of acetabular fracture
* Posterior wall = Kocker-Langenbach
* Femoral head fracture requires surgical hip dislocation
* Anterior wall/column = ilioinguinal or Stoppa with Smith-Peterson extension
98
What are the complications of femoral head fractures?
[JAAOS 2007;15:716-727]
1. Sciatic nerve injury (10-23%)
2. Osteonecrosis (6-23%)
* Older – THA
* Younger – vascularized fibular grafting or femoral osteotomy
3. HO
* Higher risk with anterior approach
4. Post-traumatic OA
99
What are the characteristics of the sacral fracture that results in spinopelvic dissociation?
[JBJS REVIEWS 2018;6(1):e7]
1. Multiplanar fracture with both horizontal and vertical fracture lines
2. Upper part of sacrum remains connected to the lumbar spine, the lower part of the sacrum remains connected to the pelvis
100
What are the classification systems to evaluate for sacral fractures?
[JBJS REVIEWS 2018;6(1):e7]
1. Denis Classification
* Type I - vertical fracture lateral to the sacral foramina
* Type II - vertical fracture through the sacral foramina
* Type III - vertical fracture medial to the sacral foramina
* Neurological injury \>50%
2. Isler Classification
* Type I - vertical fracture lateral to the L5-S1 facet
* Most stable fracture
* Type II - vertical fracture through the L5-S1 facet
* Type III - vertical fracture medial to the L5-S1 facet
* Violates spinal canal
3. Roy-Camille Classification
* Type I - flexion-type injury with resultant kyphotic deformity without fracture displacement
* Type II - flexion-type injury with posterior displacement of the cephalad segment relative to the caudad segment
* Type III - extension-type injury with anterior displacement of the cephalad segment relative to the caudad segment
4. Anatomical Classification
* H-type
* Y-type
* T-type
* U-type
101
What are the consequences of malunion following spinopelvic dissociation?
[JBJS REVIEWS 2018;6(1):e7]
1. LLD
2. Sitting imbalance
3. Chronic pain
4. Permanent neurological impairment
102
What are common radiographic findings of multiplanar sacral fractures?
[JBJS REVIEWS 2018;6(1):e7]
1. Disruption of sacral foramina
2. Paradoxical inlet view of the upper sacrum
* Representing focal kyphosis
3. Lumbosacral disruption
4. Associated pelvic ring injury
103
What are the indications for nonoperative management of spinopelvic dissociation?
[JBJS REVIEWS 2018;6(1):e7]
1. Patient unable to tolerate surgery
2. Concomitant lower extremity injuries requiring prolonged period of nonWB (~3 months) and mild deformity
104
What is the main advantage of operative management of spinopelvic dissociation?
[JBJS REVIEWS 2018;6(1):e7]
Earlier mobilization
105
What is the ideal timing of operative management for spinopelvic dissociation?
[JBJS REVIEWS 2018;6(1):e7]
1. Within 1-2 weeks
2. Urgent decompression within 24 hours in the setting of cauda equina syndrome
106
What is the role of sacral decompression in spinopelvic dissociation?
[JBJS REVIEWS 2018;6(1):e7]
1. Controversial
* Available evidence suggests decompression may be beneficial
2. In cases of neurological deficit:
* Recommend performing sacral decompression with laminectomy down to S4
107
What constructs are recommended for spinopelvic dissociation?
[JBJS REVIEWS 2018;6(1):e7][JAAOS 2018;0:1-11]
Two types of spinopelvic fixation:
* Triangular osteosynthesis
* Lumbopelvic fixation via L5 pedicle screws and iliac screws linked with a bar and SI screws
* Isolated spinopelvic fixation
* L4 and L5 pedicle screws and iliac screws linked with bars
* Indicated if SI screws not possible
* Eg comminuted S1 and S2 bodies
108
What is one method to assess adequacy of pelvic reduction in spinopelvic dissociation?
[JBJS REVIEWS 2018;6(1):e7]
Pelvic incidence +/-10 degrees of lumbar lordosis can assess sagittal plane reduction
109
What are the radiographic features, approach and fixation for the elementary acetabulum fractures?
[Hartmann Chart]
110
What are the radiographic features, approach and fixation for the associated acetabulum fractures?
[Hartmann Chart]
