Week 6 - C - Regional Adult Trauma (2) - Pelvic fractures, proximal humeral and shoulder injuries

Question 1

Pelvic fractures in younger patients occur due to high energy Older patients with osteoporosis can sustain what type of fractures from low energies to the pelvis?

Answer 1

Pubic rami fractures

Question 2

What in the hip exam during the palpation stage may indicate a pubic rami fracture?

Answer 2

Tenderness over the medial aspect of the groin

Question 3

3 main patterns of pelvic fracture exist Lateral compression fracture Vertical shear fracture An anteroposterior compression fracture

How do lateral compression fractures occur?

Answer 3

Occur due to a side impact force to the pelvis and displaces the pelvis medially

Question 4

Due to the pelvis being a ring structure, does a fracture only occur in the rami if this is what is displaced medially?

Answer 4

Fracture will also coccur elsewhere eg a sacral compression fracture

Question 5

A vertical shear fracture occurs due to axial force on one hemipelvis (eg fall from height, rapid deceleration) where the affected hemipelvis is displaced superiorly. What are at high risk of injury in this fracture?

Answer 5

The sacral nerve roots and the lumbosacral plexus are at high risk of injury and major haemorrhage may occur

Question 6

An anteroposterior compression injury may result in wide disruption of the pubic symphysis the pelvis opening up like the pages of a book – the so‐called open book pelvic fracture. What can be accompanied with pelvic fractures due to the major artery network?

Answer 6

Masive haemorrhage

Question 7

Due to the high energy typically involved, pelvic fractures are usually associated with other injuries and require prompt assessment and resuscitation How is blood loss treated?

Answer 7

Give IV fluids or blood

Question 8

Due to the high energy typically involved, pelvic fractures are usually associated with other injuries and require prompt assessment and resuscitation How is a vertical shear pelvic fracture treated?

Answer 8

Reduce the fracture using a pelvic binder and external fixation to keep it in place

Question 9

Bladder and urethral injuries (blood at the urethral meatus) may also occur and urinary catheterization may risk further injury. Urological assessment and intervention may be required. What is essential to assess? What would the presence of blood in this examination indicate?

Answer 9

A PR exam is mandatory to assess sacral nerve root function and to look for the presence of blood. The presence of blood indicates a rectal tear rendering the injury an open fracture and carries a higher risk of mortality.

Question 10

Low energy pubic rami fractures in the elderly tend to be minimally displaced lateral compression injuries How is it treated?

Answer 10

Conservative management over time

Question 11

What fracture can potentially injury the bladder?

Answer 11

A pubic rami fracture

Question 12

What forms the socket of the hip joint?

Answer 12

The acetabulum

Question 13

What is the name of depression in the head of the femur (the ball of the hip joint) and what ligament comes from this?

Answer 13

This is the fovea

The ligamentum teres (head of femur ligament) comes from this and inserts into the acetabulum

Question 14

What is the artery of the ligamentum teres? What is the supply to the head and neck of the femur?

Answer 14

Foveolar artery - branch of the obturator artery

Medial and lateral circumflex arteries give off branches that anastamose (these are the retinacular arteries)

Question 15

Acetabular fractures are usually high energy injuries in the younger patient but can be low energy in the older patient. Posterior wall fractures may be associated with a hip dislocation As the acetabulum is a difficult structure to see on xray, what view may help?

Answer 15

Oblique view on xray but can use a CT scan as it will also help with surgical planning

Question 16

Undisplaced fractures or small wall acetabular fractures are treated how? Remember the treatment of undisplaced fractures

Answer 16

Treated conservatively with splintage/immobilisation

Question 17

What is the treatment for intra-articular, unsable or displaced acetabular fractures?

Answer 17

As with most intra‐ articular fractures, unstable or displaced fractures require anatomic reduction and rigid fixation in the younger patient to reduce the risk of post traumatic OA

* better known as open reduiction internal fixation (ORIF)

Question 18

How may an intraarticular acetabulum fracture be treated in an elderly patinet?

Answer 18

May be treated with total hip replacement

Question 19

Proximal humerus fractures are common with the majority being low energy injuries in osteoprotic bone due to afall onto the outstretched hand or directly onto the shoulder.

Is fracture of the surgical or anatomical neck of the humerus more commonly seen?

Answer 19

Fracture of the surgical neck is more common - with medial displacement of the humeral shaft

Question 20

In a proximal humerus fractire, why is the shaft medially displaced?

Answer 20

Due to the pull from the pectoralis major muscle - inserts into the bicipital groove of the humerus

Question 21

Proximal humeral fractures: Many minimally displaced proximal humerus fractures are treated conservatively with a sling and gradual return to mobilization. How are displaced humeral fractures treated?

Answer 21

internal fixation (plate, screws, wires or intramedullary nail)

Question 22

How are head splitting humeral fractures treated? (communiuted dfratures)

Answer 22

Treat with arthroplasty (shoulder replacement)

Unless young patient with very good bone quality - then use internal fixation

Question 23

Anterior shoulder dislocation is much more common than posterior dislocation (the latter contributing only 2‐5% of all shoulder dislocations) What nerve can be damaged or compressed?

Answer 23

The axillary nerve

Question 24

What can anterior shoulder dislocation be caused by?

Answer 24

Caused by n excessive external rotation of the shoulder or fall on back of shoulder

Question 25

What is the lesion known as where there is the injury of the anterior (inferior) glenoid labrum of the shoulder due to anterior shoulder dislocation?

Answer 25

Bankart lesion

Question 26

If bilateral shoulder dislocations occur, what should you think?

Answer 26

Bilateral shoulder dislocations - very rare and almost always a posterior shoulder dislocation- beware of seiures being the cause

Due to muscles tightening and pulling the shoulder out of the joint

Question 27

the posterior humeral head can impact on the anterior glenoid producing an impaction fracture of the posterior head known as what?

This occurs in the anterior dislocation as the posterior humeral head passes the anterior glenoid and a compression fracture occurs

Answer 27

This would be a Hill-Sachs Lesion

Question 28

Describe the abnormalities in each picture

Answer 28

a - normal shoulder b - deltoid wasting c - anterior dislocation of the shoulder d - acromioclavicular joint dislocation

Question 29

Hamilton’s ruler sign is positive when the tip of the acromion may be joined to the lateral epicondyle of the humerus with a straight line. What does this indicate?

Answer 29

This indicates an anterior shoulder dislocation

Question 30

What is the mainstay treatment of shoulder dislocations?

Answer 30

Closed reduction (undder sedation or anaesthetic) and sling and mobilization after 4 weeks

Question 31

The patient is placed in a sling for 2‐3 weeks to allow the detached capsule to heal then rehabilitation with physiotherapy is commenced If there is an associated fracture of surgical neck or greater tuberosity, what may be required?

Answer 31

Open reduction and internal fixation if it remains displaced

Question 32

The risk of recurrent dislocation is predicted by the age of the patient at the time of initial dislocation. If the patient is less than 20 what is the likelihood of redislocation? If the patient is more than 30 what is the likelihood?

Answer 32

Patient less than 20 = 80% chance of redislocation

Patient greater than 30 = 20% chance of redislocation and decreases with age

Question 33

Some shoulder dislocations occur in patients with marked ligamentous laxity which may be idiopathic generalized ligamentous laxity / hypermobility or due to a connective tissue disorder

Name 2 of these conditions and their abnormal gene?

Answer 33

Marfan’s syndrome - mutation in the fibrillin gene

Ehler’s danlos syndrome - abnormal elastin and collagen formation

Question 34

What causes posterior shoulder dislocations?

Answer 34

The arm is internlly rotated and abducted and a posterior force is applied

Question 35

What is the typical sign on xray in posteriro shoulder dislocation? What is the treatment?

Answer 35

Light bulb sign on xray - also coracoid process is more prominent

Treatment is the same as for anterior shoulder dislocation - closed reduction and a period of immbolisation in sling

Question 36

Injuries of the acromioclavicular joint usually occur after a fall onto the point of the shoulder. They are a fairly common sporting injury. The joint can be sprained (illustrated in diagram 1), subluxed (partially dislocated) or dislocated. How are most acromioclavicular joint injuries treated?

Answer 36

Most injuries are treated with conservative management wearing a sling for a few weeks followed by physiotherapy.