AO Classification
Types
1. Supracondylar
2. Unicondylar
3. Intracondylar
Xrays
Supracondylar / Extra-condylar
Unicondylar
Intracondylar
Management
Non operative Management
Issue
Difficult
- cannot immobiise joint above
- need to keep knee stiff
- probably only indicated in the very fraile and elderly
Operative Management
Options
1. Retrograde nail
2. Lateral Plate
3. Dual plating
4. Distal femoral replacement
Issues
Plate v Nail
Shin et al. KSSTA 2017 meta-analysis
- similar time to union / rates of nonunion / rates of reoperation
https://pubmed.ncbi.nlm.nih.gov/26897137/
1. Retrograde Nail
Indications
- distal 1/3 extra-articular femur fracture
- floating knee
- concomitant pelvic and acetabular fracture
- concomitant femoral neck fracture with femoral shaft fracture
Advantage
- small incision
- good for floating knee
Disadvantage
- probably contra-indicated for intra-articular fractures
- technically difficult to perfectly restore alignment
- does destroy some cartilage in the knee from entry point / risk chronic knee pain
Surgical Technique
Pietu and Ehlinger 2017 Orthopaedics and Traumatology
- free technique article on retrograde IMN
https://pubmed.ncbi.nlm.nih.gov/27867137/
Vumedi video
https://www.vumedi.com/video/retrograde-femoral-nails/
Synthes retrograde nail technique guide
Set up
- patient supine
- put knee over radiolucent triangle / bundle of gowns
- allows entry to knee
- ensure xray imaging 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 of the distal fragment
- awl / 3.2 mm guide wire
- ream for enlarged end of retrograde nail
Pass guide wire
- consider blocking screws to aid reduction
- measure length
Ream & insert nail
- distal locking performed with jig
- proximal AP locking under xray control
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
https://pubmed.ncbi.nlm.nih.gov/7965294/
2. Lateral Plate
Advantage
- easier to fix intracondylar extension
- can be done MIPO / minimally invasive plate osteosynthesis
- plates anatomically contoured so can restore mechanical axis
Surgical Technique
Vumedi video
https://www.vumedi.com/video/distal-femur-fractures-tips-and-tricks-for-plating-and-nailing/
Synthes LISS Plate surgical technique guide
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
- anterolateral arthrotomy
- 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
Suggest
- longer plate better
- titanium plate
- reduce rigidity may be superior
- cortical non locking screws in proximal plate
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
https://pubmed.ncbi.nlm.nih.gov/15688230/
3. Dual plate
Indications
- highly comminuted fractures
- large medial gaps
Technique
Sain et al. Cereus 2019
- free article on dual plating
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6935741/pdf/cureus-0011-00000006483.pdf
Results
Bologna et al. J Orthop 2019
- increased union rates with double v single plate
https://pubmed.ncbi.nlm.nih.gov/32189888/
4. Distal Femoral Replacement
Indications
- elderly osteoporotic patient
- unreconstructable distal femur
- multiple co-morbidities
- difficulty non weight bearing
Results
Hart et al. J Arthroplasty 2017
- ORIF v distal femoral replacement in patients > 70 years old
- reoperation rate 10% in both groups
- 20% non union in ORIF
- at one year, 1/4 ORIF patients wheelchair bound, all DFR patients ambulatory
https://pubmed.ncbi.nlm.nih.gov/27449717/
Complications
Nonunion
Incidence
Yoon et al. Arch Orthop Trauma Surg 2021
- meta-analysis
- 166/2156 nonunion (5%)
- no difference nail v plate
https://pubmed.ncbi.nlm.nih.gov/32388648/
Risk Factors
Rodriguez et al. Injury 2014
- nonunion assocatiated with obesity / open fracture / infection / stainless steel plates
https://pubmed.ncbi.nlm.nih.gov/24275357/
Kiyono et al. J Orthop Surg Res 2019
- increased nonunion with medial fracture gap > 5 mm
https://pubmed.ncbi.nlm.nih.gov/31771597/
Harvin et al. Injury 2017
- 96 patients
- more rigid plate screw constructs associated with nonunion
- avoid locking screws in the diaphysis
https://pubmed.ncbi.nlm.nih.gov/28889934/
Rodriguez et al. Injury 2016
- 271 patients
- increased non union stainless steel plates c.f. titanium plates
https://pubmed.ncbi.nlm.nih.gov/27027801/
Options
1. Cortical allograft / revision lateral plating +/- medial plating
Kanakeshar et al. Injury 2017
- cortical allograft strut with autograft and lateral plate
https://pubmed.ncbi.nlm.nih.gov/28802414/
Holzman et al. CORR 2017
- addition of medial plate with autograft
https://pubmed.ncbi.nlm.nih.gov/26797911/
2. Distal Femoral Replacement
