Subtrochanteric Fractures

 

 

 Subtrochanteric Fracture Long SpiralSubtrochanteri Fracture

 

Definition

 

Fracture below lesser trochanter

Proximal 5 cm femoral shaft

Etiology

 

Young patients / high velocity injuries

Old patients / osteoporosis

 

AO classification

 

32-A3: Short transverse

 

Transverse subtrochtransverse subtroch 2

 

32-B3: Wedge, fragmented

 

Subtroch wedge

 

32-C1: Spiral, complex

 

Spiral subtroch 1Spiral subtroch

 

Russell-Taylor Classification

 

Typically used to delineate suitability for nail (type I) vs lateral fixed angle device (type II)

Modern locking nails negate this differentiation

 

Type IA: no extension into piriformis fossa. Simple fracture.

Type IB: IA + comminution

Type IIA: extension through GT into piriformis fossa

Type IIB: IIA + comminution 

 

Fixation techniques

 

Options

 

A. Plates

- fixed angle plate / 95o Dynamic Condylar Screw (DCS) plate

- locking plates

 

B. Cephalomedullary nails

- gold standard

- load sharing or load bearing, dependant on reduction

 

Recon nailNailBlade nailIntertan

Piriformis reconstruction                            Gamma nail                   TFNA with helical screw                   Intertan nail

 

Results

 

Rahme et al J Orthop Surg 2007

- RCT 58 patients

- fixed angle blade plate versus IMN

- revision rate 28% in plate group v 0% in IMN

 

Collinge et al J Orthop Trauma 2016

- 111 unstable proximal femur fractures treated with proximal locking plate

- 27% underwent second surgery for fixation failure or nonunion

 

Technique IMN

 

Vumedi tips and tricks subtrochanteric fractures

 

Subtrochanteric FractureSubtrochanteric Lateral

 

Issue

 

1. Proximal fragment flexed, in varus and externally rotated with distal fragment adducted

- iliopsoas flexes proximal fragment

- abductors cause varus of proximal fragment

- external rotators rotate proximal fragment

- adductors medialize distal fragment

 

2. Entry point difficult

 

3. Varus malreduction associated with non union

- anatomical reduction key to union

 

Results

 

Shukla et al Injury 2007

- case series of 102 subtrochanteric fractures treated with IMN

- all nonunion occurred with varus > 10 degrees

 

Afsari et al JBJS Am 2010

- clamp assisted reduction of displaced subtrochanteric fractures

- all fractures within 5 degrees of anatomical in two planes

- 43/44 fracture united

 

Kim et al Eur J Trauma Emerg Surg 2022

- systematic review of 14 studies and 1700 patients

- faster union and better outcome scores with cerclage wiring

- no difference in non union rates

 

Position

 

Lateral

- helps reduction of distal fragment to flexed proximal fragment

- easier piriformis access

 

Supine on traction table

- easier imaging

- longitudinal traction

 

Entry point

 

Greater trochanteric

- simple

- need proximal fragment reduced

 

Piriformis

- may aid reduction, as a trochanteric nail will push proximal fragment into valgus

- more difficult to obtain

 

Reduction techniques

 

Yoon et al J Orthop Trauma 2015 Tips and Tricks

 

Percutaneous

- ball tipped spikes to reduce deformity

- steinman pins to proximal and distal fragment to reduce deformity

- blocking screws laterally and posteriorly in proximal fragment

 

Open

 

1. Short transverse fracture

- clamps on proximal and distal fragments and hold reduced

- consider unicortical small plate to hold reduction

- consider blocking screws
 

Subtroch reduction

 

2.  Longer spiral fractures

- clamping and cerclage wiring with longer spiral fractures

 

Spiral subtroch 1Subtroch cerclageSubtroch cerclage

 

Subtroch cable 2subtroch cable 1subtroch cable 3

 

Complications

 

Varus malreduction

 

 Subtrochanteric Varus APSubtrochanteric Femur Varus Lateral

 

Subtrochanteric Fracture Malreduced0001Subtrochanteric Fracture Malreduced0002

 

Issue

- trendelenberg gait

- LLD

- non union

 

Non union

 

Subtroch nonunion

 

Management Options

 

A. 95 degree condylar plate

 

DCS 95 degree

 

Lotzien et al BMC Musculoskeletal Disorders 2018

- 40 patients with subtrochanteric nonunion treated with DCS

- 37/40 (92%) achieved union

- 13/40 (33%) required additional procedure for union

 

B.  Exchange nailing

 

Subtroch broken nailRevision nail

 

C.  Hemiarthroplasty / THA

 

Subtroch nonunionRevision subtrochRevision subtroch

 

Infected nonunion

 

Intertrochanteric Infected NonunionIntertrochanteric Infected Nonunion Spacer