Distal Femur Fracture

Question 1

Define distal femur fracture DFF

Answer 1

Extending from the distal metaphyseal-diaphyseal junction of the femur to the articuar surface of the femoral condyles.

Question 2

Epidemiology of DFF

Answer 2

3-6% of all femur fractures

Occur both in younger patients (high energy) and in older patients (low energy/pathological from osteoporosis or malignancy)

Also can be related to knee replacement known as peri-prosthetic fracture

Question 3

Classification of distal femur fractures

Answer 3

Type A - Extra articular

Type B - Partial articular

Type C - Complete articular

Question 4

How can partial articular fracture (type B) be further classified?

Answer 4

Sagittal fractures of lateral condyle

Sagittal fractures of medial condyle

Coronal fractures

Question 5

Explain Hoffa Fracture

Answer 5

Specific type of Type B (partial articular) articular distal femoral fracture.

There is a fracture of the posterior aspect of the femoral condyles in the coronal plane.

Usually unicondylar affecting lateral femoral condyle.

Question 6

Clinical features

Answer 6

Following a fall or traumatic injury

Severe pain in the distal thigh

Inability to weight bear

Question 7

Examination findings

Answer 7

Obvious deformity

Swelling and ecchymosis of distal thigh

If fracture extends intra-articularly -> knee effusion by haemarthrosis

Question 8

Other examinations

Answer 8

Any evidence of open fracture (5-10% cases)

Full neurovascular examination to identify potential vascular or peripheral nerve injuries

Question 9

Dx

Answer 9

Tibial plateau fracture

Haemarthrosis

Tibial shaft fracture

Question 10

Ix

Answer 10

Major trauma -> investigated and managed per ATLS protocol

Urgent bloods + coag + Group & Save
If pathology is suspected do serum caclium and myeloma screen as well

AP + lateral X-ray of knee and entire femur.

Intra-articular extension may warrant CT imaging to evaluate intra-articular involvement.

Question 11

Why are lateral view X-rays done?

Answer 11

To make sure you do not miss a Hoffa fracture

Question 12

Initial management

Answer 12

Initial realignment in A&E with analgesia/sedation.

Then immobilisation by skin traction.

If there is an open fracture manage according to open fracture protocol.

Question 13

Indications of non-operative management

Answer 13

Majority are managed surgically

Only in minimally displaced in a non-ambulatory or very co-morbid patient.

This requires a long period of immobilisation and non-weight bearing.

Question 14

Types of surgical management.

Answer 14

Retrograde intramedullary nailing (mainstay)

ORIF (mainstay)

External fixation

Question 15

Indications of retrograde intramedullary nailing.

Answer 15

Proximal extra-articular fracures

Simple intra-articular fractures

Question 16

Indications of ORIF with distal femoral plate

Answer 16

Distal fractures

Complex intra-articular fractures

Question 17

When might you do external fixation?

Answer 17

Severe comminuted or open fractures

Question 18

Management of peri-prosthetic fractures

Answer 18

May require intramedullary nailing, ORIF, revision to long stem prosthesis or distal femoral replacement.

ORIF usually if the prosthesis is stable

Long stem revision or distal femora replacement if not stable.

Question 19

Complications

Answer 19

Malunion (more common in plated fractures)

Non-union

Secondary OA especially in intra-articular cases