Distal Femur Fractures

AO Classification

 

Supracondylar

 

Distal Femoral FractureSupracondylar Femur Fracture Retrograde Nail0002

 

Distal femoral fractureDistal Femur Fracture Lateral

 

Unicondylar

 

Distal Femur Fracture Medial

 

Intracondylar

 

Distal Femur Fracture

 

Distal Femur Fracture Intercondylar 1Distal Femur Fracture Intercondylar  2Distal Femur Fracture Intercondylar CT

 

Management

 

Non operative Management

 

Issue

 

Difficult

- cannot immobiise joint above

- need to keep knee stiff

 

Operative Management

 

Options

 

1.  Retrograde nail

2.  Plate

3.  Tumour prosthesis

 

1.  Retrograde Nail

 

Supracondylar Femur Fracture Retrograde Nail0001Supracondylar Femur Fracture Retrograde Nail0001

 

Advantage

- small incision

- good for floating knee

- load sharing

 

Supracondylar Femur Fracture Retrograde Nail0003Supracondylar Femur Fracture Retrograde Nail0004

 

Disadvantage

- more difficult for intra-articular fractures

- technically difficult to perfectly restore alignment

 

Indications

- distal 1/3

- floating knee

 

Technique

 

Set up

- patient supine

- put knee over radiolucent triangle / bundle of gowns

- allows entry to knee

- ensure II for AP and lateral of knee and AP of hip for proximal locking screw

 

Entry point

- medial parapatella approach

- entry above ACL origin

- slightly medial

- ensure central in AP and lateral

- awl / 3.2 mm guide wire

- ream for enlarged end of retrograde nail

 

Pass guide wire

- measure length

 

Ream & Insert nail

- distal locking performed

- proximal AP locking under II control

 

Retrograde Nail Proximal0001Retrograde Nail Proximal0002

 

Results

 

Iannacone et al J Orthop Trauma 1994

- 41 distal femur fractures treated with retrograde nail

- 4 non unions requiring revision fixation

- 4 fatigue fractures of the IMN; changed to using minimum 12 and 13 mm rods

 

Case Nonunion

 

Retrograde Nail Nonunion0003Retrograde Nail Nonunion0004Retrograde Nail Nonunion0001Retrograde Nail Nonunion0002

 

Supracondylar Nonunion TKR0001Supracondylar Nonunion TKR0002

 

2.  Plate

 

Distal Femur Fracture Medial ORIFSupracondylar Plate ORIFSupracondylar Plate Lateral

 

 

Advantage

- easier to fix intracondylar extension

- can be done MIPO / minimally invasive plate osteosynthesis

- plates anatomically contoured so can restore mechanical axis

 

Technique

 

Position

- patient supine on radiolucent table with II

- place distal femur over radiolucent triangle / drapes

- reduces fracture

 

Incision

- incision over lateral distal femoral condyle

- longitudinal

- through skin and soft tissue

- divide ITB

- elevate vastus lateralis

- down to bone

 

Reduce intra-articular portion if required

- can elevate patella to assess reduction

- compress with bone reducing forcep

- 6.5 mm cannulated screws

- anterior and posterior to plate

- ensure not in joint / above blumensaat's

- ensure not in PFJ (distal femur is trapezoidal)

 

MIPO plate technique

- percutaneously elevate muscle off femur with elevator

- insert appropriate length plate (4 cortical screws above) with targeter

- temporarily fix distal plate to distal fragment

- if place screws parallel to joint line, the plate will be in correct valgus

- temporarily fix proximal plate percutaneously with temporary fixation screws

- obtain an indirect reduction

- check aligment and plate position AP and lateral

- attach plate with screws

 

Results

 

Schutz et al Arch Orhop Traum Surg 2005

- 62 patients average age 52 years treated with LISS plate

- union achieved in 85% patients

- 6 required bone grafting, 3 required revision of components

 

Tumour Prosthesis

 

Elderly osteoporotic patient

- unreconstructable distal femur