Intertrochanteric Fractures

DefinitionHip Intertrochanteric Fracture Type 3

 

Fracture which extends between the trochanters of the proximal femur

- lower limit is inferior border of lesser tuberosity

 

Anatomy

 

Extra capsular / well vascularized

 

The key to stability is the posteromedial cortex

 

Epidemiology

 

Elderly

- 90% > 65

- peak at 80 years

 

F:M 2:1

 

NHx 1st year

- 1/3 die

- 1/3 worse function

- 1/3 same function

 

Mechanism of injury

 

Low energy injuries in osteoporotic patient

- direct = blow to GT

- indirect = torque force secondary to fall

 

Signs

 

Leg

- shortened

- externally rotated

- groin pain with leg movement

 

Prevention

 

Judicious use of medications

- avoid confusing / sedating

 

Poor vision

- adapt home environment

- avoid slippery rugs etc

 

Adapt bathrooms for safety / stability

 

Hip pads

 

Dx Occult Hip Fractures

 

Definition

 

Hip pain

Normal Xray

 

Investigations

 

CT scan

- easily obtained in emergency departments

 

Bone Scan

- 100% sensitive at 72 hours

 

MRI

- sensitive within 24 hours

- more expensive and difficult to obtain

 

Results

 

Lubovsky et al Injury 2005

- compared CT and MRI

- MRI more accurate

- 4/6 CT inaccurate

 

Evans Classification 

 

Two main types

- Type 1 Intertrochanteric

- Type 2 Reverse Oblique

 

Stability

- depends on medial cortical reduction

 

Unstable

- collapse into varus or shaft medialises

- comminuted PM cortex

- reverse oblique

- subtrochanteric extension

 

Type 1 Intertrochanteric

 

1.  2 part undisplaced & stable

 

Hip Intertrochanteric Fracture Type 3

 

2.  2 part displaced, but stable on reduction

 

Hip Displaced Intertrochanteric Fracture

 

3.  3 part with posterolateral support (GT fracture)

 

4. 3 part without posteromedial support (LT fracture)

 

Hip Intertrochanteric fracture Type 4

 

5. 4 part without posterolateral or medial support (combination 3 and 4)

 

Four Part Inter trochanteric fracture

 

Type II Reverse Oblique Type

 

 

Inherently unstable

- 2° tendency of femoral shaft fragment to shift medially

 

Modified Boyd Classification

 

Type I   21%

- nondisplaced & stable 

 

Type II   36%

- stable, but displaced fractures

- stable construct with pin and plate

 

Type III   28%

- unstable with pin and plate

- large posteromedial comminution 

 

Type IV  15%

- intertrochanteric with subtrochanteric component

 

Isolated GT Fracture

 

Isolated Greater Trochanter Fracture

 

Management

 

Non operative

 

Issues

 

Little place for non operative treatment

 

Immobilization = Severe morbidity

- bed sores

- chest infection

- non-union

 

Indications

 

Unit for surgery

 

Incomplete fractures

 

Alam et al JBJS Br 2005

- 5 partial intertrochanteric fractures treated non operatively, 3 operatively

- no refractures

- similar length of hosptial stay

 

Operative

 

Medical Workup

 

1.  Improve any reversible medical disease

 

Otherwise surgery in first 24 hours

 

Consider Cause of fall

- exclude medical cause

- TIA / UTI / MI / Arrythmia

 

Treat

- electrolyte imbalance / anaemia

- pneumonia / UTI

- arrythmias

 

2.  Patient on anticoagulation

- operate if on plavix

- on warfarin, wait or use FFP to reduce INR < 1.6

 

Timing

 

Zuckerman et al JBJS Am 1995

- delay > 2 days increases mortality within the first postoperative year

 

Goal

 

Obtain stable anatomical reduction and allow early mobilisation

 

Options

 

Sliding Hip Screw and Plate

Intramedullary Hip Screw

Calcar Replacing Prosthesis

 

Post operative

 

Mobilise +++

 

DVT prophylaxis

- chemical and mechanical

 

Nutrition

 

Foster et al J Orthop Trauma 1990

- higher morbidity if albumin< 3 (70%) than > 3 (17%)

 

Prevent secondary fractures

- vitamin D + calcium to all patients

- bisphosphonates if tolerated

 

Sliding hip screw and Plate

 

Hip Pin and Plate APHip Pin and Plate Lateral

 

Mechanism

 

Plate is a lateral tension band whilst the sliding screw allows controlled fracture impaction

 

Contraindications

1.  No lateral buttress 

2.  Reverse oblique fracture

3.  Subtrochanteric extension

 

Technique

 

Set up

- traction table with anatomic reduction

- traction, adduction, IR

- other leg: hip and knee flexed with hip abducted to allow II

- lateral approach to femur

 

Guide wire

- centred in femoral head in 2 planes 

- tip-apex distance < 25 mm

 

Tip - apex distance

- from tip of screw to apex femoral head

- accumulative on AP and lateral

- strong predictor of cut out

- < 25 mm, virtually zero

- > 25 mm, increases cut out

 

Measure angle

- wire in centre of neck / centre of head

- usually 130o prosthesis

- often only 135o available / need to be lower in neck

- being in the centre of the head is most important

 

Ream to within 5 mm of end of wire

- tap

- insert screw / tip apex distance < 25 mm

- attach plate

 

Options for improving stability

 

A.  Valgus Osteotomy for unstable Fractures

 

Theory

- reduces shear force

- increases compression

- stronger construct

 

Technique

- 135° plate placed in at 120°

- valgises proximal fragment 

- medializes shaft

- +/- lateral wedge removed / Sarmiento Valgus Osteotomy

 

Cochrane Database Sytemic Review 2009

- no evidence for improved outcome

- higher blood loss

 

B.  Trochanteric stabilisation plate

 

Theory

- buttresses the GT and prevents lateral displacement

 

Madsen et al J Orthop Trauma 1998

- compared first generation Gamma nail / CHS and DSH/TSP in unstable fractures

- DHS/ TSP had lowest rate of varus malunion / lag screw cutout / excessive lag screw sliding with medialisation

- CHS still had lowest rate of reoperation

 

Intra-medullary Hip Screw

 

Hip Intertrochanteri Fracture IMNHip Intertrochanteric IMN Lateral

 

Mechanical Advantages

- load sharing rather than load bearing

- decreases lever arm

- supports medial cortex

- less distance for collapse

 

Theoretical Surgical Advantages

- smaller incision / mini invasive

- reduced blood loss

- shorter surgical times

 

Indications

- reverse oblique

- unstable fracture / loss of lateral buttress / loss posteromedial support

- intertrochanteric extension

- pathological fractures

 

History

 

First generation Gamma Nail (Stryker) had 5% distal femoral fracture rate

 

Reasons for distal fracture

- fit and fill caused increased distal stresses (higher fracture with 16 mm diameter nail)

- no anterior bow

- poor distal locking technique (missed holes caused fractures)

- 2 distal screws

 

Second Generation intra-medullary hip screws

 

IMHS / Gamma Nail

- trochanteric entry

- decreased distal diameter

- shorter length (180 mm v 200mm)

- only 4o valgus offset

- 125 - 130o angle

- one distal screw with jig

 

Hip Reverse Obliquity Fracture IMN

 

Results

 

Second Generation IMN v Sliding hip screws

- several prospective randomised studies

- very similar rates of complications

- similar cut out, blood loss, time of operation

- slight risk femoral fracture IMN

- learning curve for IMN (25 cases)

 

Cochrance database review 2008

- no evidence of superiority of IMN over sliding hip screw

- increased complications with nail

 

3.  Calcar replacing prosthesis

 

Indications

- salvage of failure of fixation

- severe comminution

- RA

 

Problems

- high cost

- higher morbidity / mortality

- high risk of dislocation

 

Complications

 

1.  Screw Cut Out 6%

 

Hip Pin and Plate Screw Cut outIntertrochanteric NOF Screw Cut out

 

Causes

- poor screw position

- 150° screw

- high tip apex distance

 

Options

- 95o DCS

- THR / calcar replacing prosthesis

 

THR Issues

 

A.  Cemented femoral component

- cement will come out screw holes

- Option 1:  leave screws in laterally, and strip medially to insert small screws

- Option 2:  use uncemented stem

 

B.  Length of femoral stem

- should bypass distal screw hole by 2 cortical diameters

 

C.  Calcar

- normal stem usually sufficient if LT healed back on

 

THR Post Pin and PlateIntertrochanteric NOF Calcar Replacing THR

 

Barrel Impingement / Excessive Lateral sliding / Shaft medialisation

 

Cause

 

1.  Long screw

2.  Collapse with insufficent lateral buttress

3.  Reverse obliquity fracture

 

Intertrochanteric Fracture Barrel Impingement

 

Management

 

1.  Fracture united

- remove screw

 

2.  Fracture non union

- revise fixation in young patient

- THR

 

Lateral Slide Off Proximal Fragment

 

Femoral medialisation

 

Due to

- insufficient lateral cortex

- reverse obliquity fracture

 

Use 95° plate

 

Non Union

 

Uncommon / 1%

- exclude infection

 

Presentation

- continued pain (case 1)

- hardware failure (case 2)

 

Case 1

 

NOF Intertrochanteric Non unionNOF Intertrochanteric Nonunion CT

 

Case 2

 

Hip Broken Intertan NailHip Broken Intertan Non Union salvage

 

Options

 

A. Closing lateral wedge valgising osteotomy + graft

- success 90% / indicated in younger patients

B.  95 degree DCS Plate

C.  Revision IMN

D.  THR

 

Infection 2-5%

 

Intertrochanteric Infected NonunionIntertrochanteric Infected Nonunion Spacer

 

Malrotation

 

Cause

- posterior sag of femur in unstable fracture

- get malrotation if use excessive IR to "reduce" fracture on II

 

Periprosthetic fracture

 

Usually fracture at tip of plate

- remove distal screws and insert retrograde nail