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1

What is the classification of hemmoragic shock?

Class III/IV requires administration of blood products.

Manifests as:

Increases in heart rate and systemic vascular resistance

Decreases in cardiac output, pulmonary capillary wedge pressure, central venous pressure, and mixed venous oxygen saturation

2

What is the mechanism of TXA?

Tranexamic acid is a synthetic analogue of lysine that can be used to prevent excessive bleeding. Its mechanism of action is competitive inhibition of plasminogen activation.

3

Define damage control orthopedics

Damage control orthopaedic principles involve staging the definitive care of the patient to avoid adding to the early overall physiologic insult

4

How does ultrasound help heal bone fractures?

Ultrasound—delivers small cumulative doses of ultrasound energy; thought to induce microfracture and healing response; 30 mW/cm2pulsed wave ultrasound has been shown effective for healing acute fractures.

Electromagnetic—attempts to promote healing by directing integral ion flow at cellular level of bone

5

What antibiotics do you give for open fractures?

Antibiotics—usually started immediately. Antibiotic bead pouch with methylmethacrylate, tobramycin, and/or vancomycin may be used to initially manage highly contaminated wounds.

Types I and II—first-generation cephalosporin (cefazolin) for 24 hours

Type III—cephalosporin and aminoglycoside for 72 hours after injury or not more than 24 hours after each débridement or soft tissue coverage

Heavily contaminated wounds and farm injuries—cephalosporin, aminoglycosides, and high-dose penicillin

Freshwater wounds—fluoroquinolones (ciprofloxacin, levofloxacin) or third- or fourth-generation cephalosporin (ceftazidime)

Saltwater wounds—doxycycline and ceftazidime or a fluoroquinolone

6

Tetanus prophylaxis

Tetanus is caused by the exotoxin of Clostridium tetani, which produces convulsion and severe muscle spasms with a 30%–40% mortality rate.

Required tetanus prophylaxis treatment is based on the characteristics of the wound and the patient’s immunization status.

Tetanus-prone wounds are more than 6 hours old, are more than 1 cm deep, have devitalized tissue, and are grossly contaminated.

Patient with an unknown tetanus immunization status or who has received fewer than three tetanus immunizations and who has a tetanus-prone wound should receive tetanus and diphtheroid toxoid and human tetanus immunoglobulins (intramuscular injection of toxoid and immunoglobulin should occur at different sites).

Patient with unknown tetanus immunization status or who has received fewer than three tetanus immunizations and who has a non–tetanus-prone wound should receive only tetanus toxoid.

Fully immunized patient should receive tetanus toxoid if the wound is severe or is more than 24 hours old, or if the patient has not had a booster in the past 5 years.

7

osteomyelitis

Diagnosis

Definitive diagnosis—by bone biopsy. Bone culture and microscopic pathology. Bone culture may have high false-negative rate. Microscopic pathology to evaluate for inflammatory changes consistent with infection.

Other tests—may be used in combination with physical examination (draining wound, pain) to confirm diagnosis

Chronic draining wounds can differentiate into squamous cell carcinoma and should undergo histologic analysis when excised.

MRI—95% sensitive and 90% specific

Technetium (Tc) 99m (99mTc) study—85% sensitive and 80% specific

Indium (In) 111 study—95% sensitive and 85%–90% specific

Treatment—based on grade and host type (Cierny/Mader classification)

Grade

Grade I—intramedullary; débridement by intramedullary reaming

Grade II—superficial, involves cortex, often seen in diabetic wounds; curettage

Grade III—localized, involves cortical lesion with extension into medullary canal; requires wide excision, bone grafting, and perhaps stabilization

Grade IV—diffuse, indicates spread through cortex and along medullary canal; wide sequestrectomy, muscle flap, bone graft, and stabilization

Host

A—normal healthy patient

B—locally compromised (vasculopathic)

C—not considered a medical candidate for surgery; may require suppressive antibiotics

8

LEAP study results

Multicenter prospective study of severe lower extremity trauma in the U.S. civilian population. Key findings and recommendations include:

Injury severity scoring systems do not provide valid predictive value to guide amputation decision.

Absence of plantar sensation on presentation is not predictive of extremity function or return of plantar sensation at 2-year follow-up.

At 2- and 7-year follow-up, no difference in functional outcome between patients who underwent limb salvage surgery and those who underwent amputation

Outcomes found to be affected more by patient’s economic, social, and personal resources than by the injury treatment method

Patients with mangled extremity injuries have poor outcomes at 2 years. Outcomes continue to worsen between 2 and 7 years’ follow-up. Factors associated with poor outcome include older age, female gender, nonwhite race, lower level of education, current or prior smoking history, poor economic status, low self-efficacy, poor health status prior to injury, and involvement in legal system to obtain disability.

Patients presenting with mangled lower extremity injuries are less agreeable and more likely to drink alcohol, to smoke, to be poor and uninsured, and to be neurotic and extroverted in comparison with population norms.

Patients who undergo below-knee amputation function better than those who undergo above-knee amputation. Patients undergoing through-knee amputation have the poorest function.

9

Review the biomechanics of fracture healing

Stability and fracture healing

Stability determines strain

Absolute stability

Relative stability

Strain determines type of healing

Strain is defined as change in fracture gap divided by the fracture gap (ΔL/L).

Highest fracture site strain is seen in a simple fracture that is fixed with a gap (incompletely reduced).

Strain less than 2% results in primary bone healing (endosteal healing).

Strain 2%–10% results in secondary bone healing (enchondral ossification).

Strain greater than 10% does not permit bone formation.

Relative stability

Micromotion at fracture site under physiologic load leads to callus formation.

Strain decreases as callus matures, leading to increased stability.

If there is too much motion, callus becomes hypertrophic as it tries to spread out force, and hypertrophic nonunion can result.

Examples: casts, external fixators, IM nails, bridge plates

Absolute stability

No motion at fracture site under physiologic load

Bone heals through direct healing (no callus).

Strain is low or zero.

Healing times are longer and more difficult to confirm by radiography.

Implants must have longer fatigue life.

Examples: oblique fractures fixed with lag screws and transverse fractures fixed with compression plating technique

Healing in different bone types

Diaphyseal (cortical)

Decreased blood supply leads to longer healing times.

Bone is more amenable to compression techniques (in short oblique/transverse fractures).

Strain is concentrated over a smaller surface area.

Cancellous (metaphyseal)

Larger surface area and better blood supply

Strain is lower as forces spread out over larger area.

Healing is more rapid.

However, joint surfaces tolerate very little malreduction (<2 mm), so there is often increased time to bear weight versus diaphyseal fractures.

10

Biomechanics of ORIF 

Lag screws

Provide rigid interfragmentary compression (absolute stability)

Force is concentrated over a small area (around screw), so typically a plate is needed to protect/neutralize the deforming forces.

Position screws

Compress plate to bone but do not provide interfragmentary compression

Friction between screw, plate, and bone resists pullout or bending.

Plating

Plate length matters more for bending stability than number of screws in plate.

Torsional stability is more affected by position of screws (end hole must be filled).

Longer plates spread the strain over more area (working length).

To increase bending stiffness of a plate, decrease the working length by placing screws closer to the fracture site (a 10-hole plate centered at a fracture with screws in holes 1, 5, 6, and 10 has a higher bending stiffness than one with screws in holes 1, 3, 8, and 10).

Plates are load bearing—will stress shield area they cover; important to protect area temporarily if plate removed after healing

Compression plate function

Plate design (oval holes) or use of compression device allows plate to apply compressive forces across fracture.

Provides absolute stability when properly applied

Relies on friction between plate and bone (needs at least some nonlocking screws)

May need to be prebent to achieve compression of both near and far cortex

Insertion order is neutral position, then compression on opposite side of fracture, then lag screw (if being placed through plate).

Tight contact of plate to bone when initially applied causes decreased periosteal blood flow and temporary osteopenia.

Bridge plate function

Primarily for comminuted fracture patterns

Plate “bridges” area of comminution with fixation above and below fracture.

Allows some elastic deformation (relative stability)

Use of screws very close to fracture should be avoided.

Number and types of screws to insert are fracture dependent—no clear, widely accepted guidelines.

Nonlocking screws compress plate to bone and can be used to lag in fragments; locking screws provide angular stability in short metaphyseal segments or in osteoporotic bone.

Buttress plate function

Plate provides support at 90-degree angle to fracture—typically in depressed metaphyseal/articular fractures that have been reduced.

Can provide absolute stability to metaphyseal fragments

Submuscular/percutaneous plating

To preserve biology at fracture site, plate may be placed in submuscular plane by sliding through small incisions proximal or distal to fracture and avoiding exposure of fracture site.

Typically used in bridge mode, although not exclusively

Advantage: decreased soft tissue and biologic compromise

Perfusion of both medulla and periosteum is better retained.

Disadvantage: more prone to malreduction/malrotation

Locked plating

Screws have threads in head that lock into corresponding holes in plate

Fail simultaneously rather than sequentially

Stability does not depend on friction between plate and bone.

Provides fixed-angle construct—similar to blade plate

Most useful in unstable short-segment metaphyseal fractures and osteoporotic bone

Fractures in which locking plate use is supported by data include

Periprosthetic fractures

Proximal humerus fracture

Intraarticular distal femur and proximal tibia

Humeral shaft nonunion in the elderly

Unicortical locked screws

Typically for metaphyseal bone

Similar in pullout strength to bicortical locked screws in good-quality diaphyseal bone (but rare indications for use there)

Weaker in torsion than bicortical screws

Bicortical locked screws: biggest advantage is in osteoporotic diaphyseal bone

Multiaxial screws

May increase options for fixation in working around periprosthetic fractures

No advantage in strength or pullout

“Hybridization” describes the use of both locking and nonlocking screws in combination. This allows for both compression and fixed-angle support.

IM nails

Load-sharing devices—relative stability

Stiffness depends on:

Material

Stainless is stiffer than titanium.

Size

Increased diameter leads to increased stiffness at a ratio of radius to the power of:

3 in bending

4 in torsion

Wall thickness

Larger = stiffer nail

Radius of curvature of femoral nails is typically less than anatomic, improving frictional fixation.

A large mismatch of curvature, however, results in difficult insertion, increased risk of intraoperative fracture, and malreduction in extension.

Nails resist bending very well and require interlocks to resist torsion or compression loads.

Working length is the portion of the nail that is unsupported by bone when loaded.

Increased working length produces increased interfragmentary motion and may delay union.

Advantage of intramedullary position is decreased lever arm for bending forces (especially useful in peritrochanteric fractures vs. plate-and-screw construct).

11

Key point on SC joint injuries

Sternoclavicular dislocation—“serendipity” view or CT scan reveals dislocation of sternoclavicular joint

Anterior dislocation—more common, treated by closed reduction. The majority will remain unstable regardless of initial treatment modality, but these are typically asymptomatic.

Posterior dislocation—more serious—30% associated with significant compression of posterior structures. May cause dysphagia or difficulty breathing and sensation of fullness in the throat. Treated by closed reduction with a towel clip in the operating room. A thoracic surgeon should be on standby.

Chronic dislocation—treated by resection of the medial clavicle, with preservation and reconstruction of costoclavicular ligaments

Pseudodislocation—medial clavicular epiphysis is the last to close, at a mean age of 25 years. In younger patients, sternoclavicular dislocation is often a Salter-Harris type I or II fracture.

12

Clavicle Fractures

classified by thirds

Middle—80%

Distal—15%

Medial—5%

Associated injuries—open clavicle fractures associated with high rates of pulmonary and closed-head injuries

Treatment

Nonoperative treatment: midthird fracture has traditionally been treated nonoperatively, in a sling.

No difference in outcome between regular sling and figure-eight bandage

Risk of nonunion after midshaft fracture is higher in female and elderly patients and with fractures that are displaced, shortened more than 2 cm, or comminuted.

Lateral fractures have higher rates of nonunion compared with midshaft fractures.

Operative treatment

Middle third

Have higher rates of nonunion and decreased shoulder strength and endurance (≈15%)

Absolute surgical indications: open fracture, displaced fractures with skin compromise, associated neurovascular injury

Relative surgical indications: floating shoulder (associated scapular neck fracture), shortening greater than 15–20 mm, complete displacement, comminution

Prospective randomized study comparing operative with nonoperative treatment of displaced midthird clavicle fractures: operative treatment group had a 10-point improvement in Constant and DASH (Disabilities of the Arm, Shoulder, and Hand) scores at all time points, earlier time to union, and statistically fewer nonunions, symptomatic malunions, and complications than the nonoperative treatment group.

Distal third

Some recommend operative treatment of distal fractures that extend into the acromioclavicular joint, whereas others recommend a late Mumford procedure.

Type II distal clavicle fractures, which involve displacement, have the highest nonunion incidence, but many nonunions are asymptomatic. Nonoperative and operative management approaches provide similar results. Operative decision based on amount of displacement and individual patient demands. For example, sling and early ROM are the best treatments for middle-aged woman with 100% displacement of a distal clavicle fracture.

Fixation options

Plate—typically dynamic compression plate; applied to superior aspect (better biomechanical strength but more prominent → hardware removal) or to anterior-inferior aspect (less hardware removal).

IM rod and screw—may be inserted percutaneously; higher rates of hardware irritation and complication

Avoid Steinmann pins, especially nonthreaded—can migrate.

13

AC joint dislocations

 

Classification and Treatment

Classification—classified by extent of involvement of the ligamentous support and direction and magnitude of displacement. Coracoclavicular (CC) and acromioclavicular (AC) ligaments may be ruptured.

Type I—sprain of AC joint

Type II—rupture of AC ligaments and sprain of CC ligaments

Type III—rupture of both AC and CC ligaments

Type IV—clavicle is buttonholed through trapezius posteriorly

Type V—trapezius and deltoid detached

Type VI—Clavicle is dislocated inferior to coracoid

Treatment

 

Types I and II—always treated with brief immobilization in a sling

 

Type III—may be treated nonoperatively, but many advocate early operative treatment in patients who are heavy laborers and throwers. Weaver-Dunn procedure is the treatment of choice.

Types IV to VI—usually treated operatively

14

What is a scapulothoracic dissociation?

result of significant trauma to chest wall, lung, and heart. Severe cases are treated essentially with a closed forequarter amputation.

Associated with:

Brachial plexus avulsion

Subclavian or axillary artery injury

AC dislocation, clavicle fracture, and sternoclavicular dislocation

Mortality rate of 10%

Diagnosis should be suspected when there is a neurologic and/or vascular deficit. More than 1 cm of lateral displacement of the scapula on a chest radiograph is also suggestive.

Management

Hemodynamically stable: angiography before surgery. Vascular injury may potentially be treated nonoperatively owing to the extensive collateral network around the shoulder.

Hemodynamically unstable: high lateral thoracotomy or median sternotomy to control bleeding

Musculoskeletal injury treatment is controversial but is often nonoperative if vascular repair is not undertaken.

Functional outcome is based on severity of associated neurologic injury.

Floating shoulder—fracture of the glenoid neck and clavicle

Some recommend fixation when a clavicle fracture is associated with a displaced glenoid neck fracture, whereas others do not consider it necessary (depends on stability of superior shoulder suspensory complex [SSSC]).

15

Proximal Humerus Fractures:

 

Classification and Treatment

Neer classification (Neer defines “part” as displacement of >1 cm or angulation of >45 degrees); parts are articular surface, greater tuberosity, lesser tuberosity, and shaft

One-part—nondisplaced or minimally displaced fracture (often of the humeral neck)

Two-part—displacement of tuberosity of more than 1 cm; or surgical neck with head/shaft angled or displaced

Three-part—displacement of the greater or lesser tuberosities and articular surface

Four-part—displacement of shaft, articular surface, and both tuberosities.

“Head splitting” is a variant, with split through the articular surface (usually requires replacement for treatment).

Treatment

One-part—sling for comfort and early mobilization

Two-part—repair of the displaced tuberosity with sutures or tension band wiring; surgical neck fractures can normally be managed nonoperatively.

Unstable, nonimpacted fractures may be treated with closed reduction with percutaneous pinning (CRPP), ORIF with locking plate fixation, or IM nailing

Varying humeral nail designs. Straight nails are placed through a more central entry point (through superior articular cartilage) that can provide additional point of fixation. Nails with proximal bend are placed through an entry point just medial to the rotator cuff insertion.

Immediate physical therapy during nonoperative management results in faster recovery.

Greater tuberosity fractures are displaced superiorly and posteriorly owing to deforming pull of supraspinatus, infraspinatus, and teres minor. Healing in a displaced position would block abduction and external rotation.

Surgery is indicated for displacement greater than 5 mm. In young patients with good bone, screws alone can be used, but nonabsorbable suture technique should be used in older patients.

Three-part

ORIF for young patients, with repair of the tuberosities or rotator cuff

Screw cutout is the most common complication following ORIF with a periarticular locking plate.

Hemiarthroplasty for older patients, with repair of the rotator cuff/tuberosities

Four-part—same as for three-part

Humeral height can be judged most reliably using the superior border of the pectoralis major insertion.

Nonanatomic placement of the tuberosities leads to significant impairment in external rotation kinematics and an eightfold increase in torque requirements.

Complications

Avascular necrosis (AVN)

Factors associated with humeral head ischemia (Hertel criteria):

Disruption of the medial periosteal hinge

Medial metadiaphyseal extension less than 8 mm

Increasing fracture complexity

Displacement greater than 10 mm

Angulation greater than 45 degrees

Neurovascular injury

Axillary nerve injury

Lateral pins placed during CRPP place the nerve most at risk.

Anterior pins placed during CRPP risk the biceps tendon, cephalic vein, and musculocutaneous nerve.

Hardware failure

The most common complication after locking plate fixation is screw cutout.

Nonunion

Most common after two-part fracture of surgical neck

Nonunion of greater tuberosity following arthroplasty—loss of active shoulder elevation

16

Humeral Shaft Fractures:

 

Shaft fracture

Classification by location and fracture pattern

Treatment

Nonoperative treatment: functional brace if there is less than 20 degrees of anterior angulation, less than 30 degrees of valgus/varus angulation, or less than 3 cm of shortening; contraindicated in patients with associated brachial plexus palsy

Operative treatment: open fracture, floating elbow, polytrauma, pathologic fracture, associated brachial plexus injury

ORIF

Probably the gold standard

Proximal two-thirds—anterolateral approach

Distal half—posterior approach

Need for radial nerve exploration—lateral approach

Higher union rates and decreased secondary operations

Weight bearing to tolerance is safe after plate fixation.

IM nail

Possibly better for segmental or shaft/proximal humerus combination as well as pathologic fracture

Complication rate may be higher and may be associated with higher rates of reoperation than plate fixation.

Distal locking screw risks

Radial nerve with lateral-to-medial screw

Musculocutaneous nerve with anteroposterior screw

Complications

Radial nerve palsy (5%–10%)

When to observe:

The vast majority (up to 92%) resolve with observation for 3 to 4 months.

Brachioradialis followed by extensor carpi radialis longus (wrist extension in radial deviation) are the first to return, whereas extensor pollicis longus and extensor indicis proprius are last to return.

When to explore

Open fracture

A higher likelihood of transection

Perform ORIF of fracture at time of exploration.

Controversial whether to observe or explore

Secondary nerve palsy (i.e., after fracture manipulation)

Spiral or oblique fracture of distal-third (Holstein-Lewis) fracture

Management of palsy that does not recover is also controversial as to timing of electromyography, nerve exploration, and tendon transfers.

Nonunion—treated with compression plate with bone graft if atrophic.

Shoulder pain; some papers report a high incidence of shoulder pain, whereas others do not. Overall incidence is higher with IM nails.

17

Distal humerus

 

Single Column

Classification

Classified as Milch types I and II lateral condyle fractures (more common) and types I and II medial condyle fractures.

In type I lateral condyle fractures the lateral trochlear ridge is intact, and in type II lateral condyle fractures there is a fracture through lateral trochlear ridge (Fig. 11.4).

Treatment—type I nondisplaced: immobilize in supination (lateral condyle fracture) or pronation (medial condyle fracture); otherwise, CRPP or ORIF

Complications: cubitus valgus (lateral) or cubitus varus (medial), ulnar nerve injury, and degenerative joint disease (DJD)

18

Distal Humerus 

Both Column fractures

Presentation: five major fragments identified

Capitellum/lateral trochlea

Lateral epicondyle

Posterolateral epicondyle

Posterior trochlea

Medial trochlea/epicondyle

Treatment (goal is early ROM with <3 weeks of immobilization)

ORIF using a posterior approach with two plates applied to either column

Biomechanical studies support both parallel placement (one plate medial, one plate lateral) and perpendicular placement (one plate medial, one plate posterolateral) configurations

Used with olecranon osteotomy or triceps split/peel (final muscle strength similar with both)

In an open fracture, ORIF by means of a triceps split through the defect should be used, producing better results than osteotomy.

Very distal fractures are more difficult and frequently require reoperation (almost 50%) for stiffness

No benefit from ulnar nerve transposition during ORIF

“Bag-of-bones” technique—reasonable in patients with dementia and those who have severe medical comorbidities that prevent surgical treatment

Total elbow arthroplasty—useful for comminuted fractures in patients with low functional demands older than 65 years, particularly those with osteoporosis or rheumatoid arthritis

Complications

Stiffness

Most common complication

Initially treated with static-progressive splinting

Loss of elbow muscle strength of 25%

Ulnar nerve injury

Treated with anterior transposition

 

Heterotopic ossification (4%)

Infection

19

Capitellar fractures

Treatment

Type I (complete fracture)—if nondisplaced, splinted for 2 to 3 weeks and then allowed motion; if displaced more than 2 mm, ORIF.

Type II (shear fracture of articular cartilage)—if nondisplaced, splinted for 2 to 3 weeks and then allowed motion; if displaced, fragment excision.

Type III (comminuted fractures)—if displaced, fragment excision.

Type IV (fracture involving capitellum and trochlea)—ORIF; lateral approach recommended

Complications: nonunion (1%–11% with ORIF), olecranon osteotomy nonunion, ulnar nerve injury, heterotopic ossification (4% with ORIF), and AVN of capitellum

20

Olecranon Fractures

Treatment

Less than 1–2 mm displaced—splinted at 60–90 degrees for 7–10 days, followed by gentle active ROM exercises.

Tension band—stainless steel wire or braided cable, not braided suture material

The wire loop should be dorsal to the midaxis of the ulna, thus transforming tensile forces at the fracture site into compressive forces at the articular surface.

Kirschner wires are (K-wires) buried in anterior cortex for increased stability. Protrusion through the anterior cortex, however, is associated with reduced forearm rotation.

Migration of K-wires and prominent or painful hardware occurs in 71%.

Compared with K-wires that are positioned into the intramedullary canal, wires that penetrate the volar ulna cortex are associated with a higher potential risk of diminished forearm rotation.

IM screw fixation—inadequate by itself, but a properly placed 7.3-mm partially threaded screw with tension band wiring works well.

Plate fixation (dorsal or tension side)—preferred technique for oblique fractures that extend distal to the coronoid process; more stable than tension band wiring

Excision with triceps advancement—used for nonreconstructible proximal olecranon fractures in elderly patients with low functional demands. Reattached close to the articular surface. Resection of more than 50% of the olecranon should be avoided.

Complications: decreased ROM, DJD, nonunion, ulnar nerve neurapraxia, and instability

21

Coronoid Fractures

Classification

Regan and Morrey classification

Type I—fracture of the tip of the coronoid process

Type II—fracture of 50% or less of coronoid

Type III—of greater than 50% of coronoid

O’Driscoll classification

Tip

Anteromedial process—caused by a varus posteromedial rotatory force and may be associated with posteromedial instability. Injury is at the attachment site of the anterior bundle of the medial collateral ligament.

Basal

Treatment

Type I—associated with episodes of elbow instability. If instability persists, cerclage wire or No. 5 suture is applied through drill holes; if instability does not persist, no operation.

Types II and III—ORIF helps restore elbow stability; stability must be confirmed before nonoperative treatment begins.

Complications: instability (particularly medial) and DJD

22

Radial Head Fractures:

 

Classification and Treatment

Type I—nondisplaced

Type II—partial articulation with displacement

Type III—comminuted fractures involving the entire head of the radius

Type IV—fractures associated with ligamentous injury or other associated fractures

Treatment

Type I—Splinted for no more than 7 days, and then allowed motion.

Type II—nonsurgical treatment with analgesics and active ROM as symptoms resolve if elbow is stable and there is no block to motion with good reduction. Otherwise, ORIF. Surgery provides better results (90%–100% good or excellent).

Type III—replacement of the radial head, usually with a metal implant. ORIF if fewer than three pieces. Excision only in elderly patients with low functional demands.

Type IV—requires surgical repair: either ORIF or metallic radial head replacement must be used. Excision must not be done without addition of radial head implant.

Safe zone for ORIF of radial head/neck is 110-degree arc (i.e., 25%) along lateral side, defined by radial styloid and Lister tubercle.

Complications

Loss of motion

Posterior interosseous nerve (PIN) injury

Arm is pronated to avoid injury.

Radial shortening if Essex-Lopresti injury

Synovitis if a silicone elastomer (e.g., Silastic) radial head implant is used

23

Elbow Dislocation

24

Lafontaine predictors of instability for distal radius fractures:

patients with three or more factors have high chance of loss of reduction

dorsal angulation > 20°

dorsal comminution > 50%, palmar comminution, intraarticular comminution

initial displacement > 1cm

initial radial shortening > 5mm

associated ulnar fracture

severe osteoporosis

radial shortening is the most predictive of instability, followed by dorsal comminution

25

Radiographic parameters for distal radius fractures:

 

View

Measurement

Normal

Acceptable criteria 

APRadial height13mm< 5mm shortening 

 Radial inclination23°change < 5° 

 Articular stepoffcongruous< 2 mm stepoff 

LateralVolar tilt11°dorsal angulation < 5° or within 20° of contralateral distal radius 

CT 

26

Young-Burgess Pelvic fracture classification

Lateral compression (LC)—all have anterior transverse pubic ramus fracture.

LC I—sacral compression fracture

LC II—posterior iliac wing fracture

LC III—contralateral anteroposterior compression injury (windswept pelvis)

Thought to be due to a rollover mechanism

Anteroposterior compression (APC)—all have symphyseal diastasis.

APC I—symphyseal diastasis less than 2.5 cm

Stretching of anterior SI ligaments

APC II—symphyseal diastasis greater than 2.5 cm with widening of SI joint anteriorly

Rupture of sacrotuberous, sacrospinous, and anterior SI ligaments

APC III—symphyseal diastasis greater than 2.5 cm with complete disruption of SI joint, both anteriorly and posteriorly. Highest transfusion requirements.

Rupture of sacrotuberous, sacrospinous, and anterior and posterior SI ligaments

Complete separation of hemipelvis from pelvic ring

Vertical shear (VS)

Usually due to a fall. Vertical displacement of hemipelvis commonly with complete disruption of the SI joint.

Combined mechanism

Stable types are lateral compression type I and anteroposterior compression type I

APC II, APC III, LC III, and VS may involve stretching and tearing of veins and arteries causing hemorrhagic shock

Associated injuries

APC pattern has associated urethral and bladder injuries. Incidence of spleen, liver, bowel, and pelvic vascular injury increases from APC I to APC III categories.

LC I and LC II patterns have associated brain, lung, and abdominal injuries.

LC III pattern usually due to a crush injury to pelvis, sparing other organs from injury

Vertical shear mechanism fracture injury pattern and mortality similar to those for APC II and APC III patterns.

 

Combined mechanism pattern has organ injury pattern similar to lower-grade APC and LC patterns

Cause of death in LC pattern is primarily brain injury, whereas in APC pattern, causes are primarily shock, sepsis, and ARDS.

27

Tile Classification of Pelvic Fractures

Stable (posterior arch intact)

Avulsion fractures

Iliac wing fractures

Transverse sacral fractures

Partially stable—rotationally unstable and vertically stable

External rotation

Anterior pelvic disruption alone

Anterior sacroiliac ligaments too

Anterior and posterior sacroiliac ligaments

Lateral compression

Ipsilateral

Contralateral (bucket-handle)

Bilateral

Unstable (complete disruption of posterior arch)

Unilateral

Bilateral but one side B type and one side C type

Bilateral C type

28

Discuss Pelvic Fracture Treatment

General principles

Emergent treatment: control hemorrhage and provisionally stabilize pelvic ring

Important to establish and follow a treatment protocol to avoid variation in treatment decision making

85% of bleeding due to venous injury, only 15% have arterial source

Volume resuscitation and early blood transfusion

Pelvic binder or wrapped sheet. External rotational deformity may be reduced by taping feet together.

Angiographic embolization

Pelvic packing, initially popularized in Europe, provides tamponade of venous bleeding.

External fixation

Placed before emergent laparotomy

Skeletal traction—for vertically unstable patterns

Pelvic C clamp (rarely used)

Nonoperative treatment

Indicated for stable fracture patterns

Weight bearing as tolerated for isolated anterior injuries

Protected weight bearing for ipsilateral anterior and posterior ring injuries

Operative treatment

Indications

Symphysis diastasis greater than 2.5 cm. Extent of actual diastasis may not be apparent if patient is put in a pelvic binder before initial AP pelvic x-ray. Intraoperative stress view exam may be required.

Anterior and posterior sacroiliac ligament disruption

Vertical instability of posterior hemipelvis

Sacral fracture with displacement greater than 1 cm

Anterior injuries

ORIF with plate fixation

External fixation via pins through anterior-inferior iliac spine (biomechanically stronger than iliac wing but less well tolerated clinically) or iliac wing

The lateral femoral cutaneous nerve is most at risk.

Anterior subcutaneous internal fixator offers the benefits of decreased open surgical dissection while limiting problems associated with standard external fixation.

Can cause femoral nerve injury (impairs quad function)

Injury to lateral femoral cutaneous nerve in third of patients

Heterotopic ossification (usually asymptomatic) is most common complication

Posterior injuries

Percutaneous iliosacral screw fixation

Vertical sacral fractures are at higher risk for loss of fixation.

Anterior plate fixation across the sacroiliac joint

Posterior transiliac sacral bars or sacral plating

Spinal-pelvic fixation considered for bilateral sacral fractures

Vertically unstable patterns with anterior and posterior dislocations

Anterior ring internal fixation and percutaneous sacroiliac screw has been shown to be most stable fixation construct.

Spinal-pelvic fixation may also be considered.

Complications

Severe life-threatening hemorrhage

Highest risk with APC II, APC III, and LC III patterns

Neurologic injury

Urogenital injury or dysfunction

Urethral stricture most common in men

Dyspareunia and need for cesarean section childbirth common in women

Malunion

Nonunion

DVT and/or pulmonary embolus

DVT is the most common complication if thromboprophylaxis is not used.

Infection—open fracture and associated contaminated laparotomy

Death

Risk factors for death identified during initial treatment:

Blood transfusion requirement in first 24 hours

Unstable fracture type (APC II, APC III, LC II, LC III, vertical shear, combined mechanism)

Open fracture

Chronic instability following pelvic fracture can be best assessed with single-leg stance views (Flamingo views)

29

Sacral Fracture Review

Diagnosis

Mechanism of injury—high energy

Radiographs—AP pelvis, inlet, outlet, and lateral views

CT (usually required)

Classification—Denis classification (Fig. 11.8) based on fracture location relative to foramen (zones I, II, and III)

Treatment

Nonoperative

Indicated for stable and minimally displaced fractures

Weight bearing as tolerated for incomplete fractures in which the ilium is contiguous with the intact sacrum (e.g., anterior impaction fractures from lateral compression mechanism or isolated sacral alar fractures)

Touch-toe weight bearing for complete fractures

Operative treatment

Indicated for displaced fractures (>1 cm)

Percutaneous iliosacral screws

Appropriate fluoroscopic visualization of anatomic landmarks is mandatory before surgery.

The pelvic outlet radiograph allows optimal visualization of the S1 neural foramina to avoid injury.

The lateral sacral view identifies the sacral alar slope and minimizes risk to the L5 nerve root.

High incidence of sacral dysmorphism (20%–44%). Sacralization of L5 or lumbarization of S1. Risk of anterior screw penetration causing neurologic injury is much higher with anterosuperior sacral concavity (Fig. 11.9).

Radiographic signs of sacral dysmorphism best seen on outlet view: prominent mammillary processes, laterally downsloping sacral ala, residual vestigial disc space between S1 and S2, top of iliac wing at level of L5–S1 instead of at L4–5, noncircular S1 anterior neural tunnel

Radiographic signs of sacral dysmorphism best seen on axial CT scan: peaked or prow-shaped sacral promontory, tongue-in-groove sacroiliac articulation, oblique and narrow S1 sacral ala, wider S2 alar channel

Posterior plating

Transiliac sacral bars

Open foraminal decompression considered for neurologic injury associated with zone II fracture

Complications

Neurologic injury

Highest incidence with displaced zone II fractures

L5 nerve root usually involved with zone II fractures

Cauda equina syndrome can be associated with zone III injuries.

Chronic low back pain

Malunion

30

Acetabular Fracture Classification review

A systematic evaluation can be used to classify most acetabular fractures using plain radiographs (see Fig. 11.10):

Examine the iliopectineal and ilioischial lines.

If both lines are intact:

PW fracture

If only one line disrupted:

Iliopectineal line

AW fracture

AC fracture

Ilioischial line

PC fracture

PC and PW fracture

If both lines disrupted:

Look at the obturator ring and determine whether it is intact.

Obturator ring intact

Transverse fracture

Transverse/PW

Obturator ring disrupted

Look at iliac wing.

Iliac wing intact

T-type

Iliac wing disrupted

AC/PHT

ABC fracture

Typically used to evaluate posterior injuries, articular fragments, marginal impaction, and congruency of the hip joint

Axial CT may be useful to aid in fracture classification.

Vertical fracture line

Transverse or T-shaped fracture

If the wall can clearly be visualized, then AW or PW fracture

Horizontal fracture line

Column fracture

Sequential axial CT cuts that demonstrate no intact support between the acetabular articular surface and axial skeleton through the sacroiliac joint indicate ABC fracture.