PRINCIPLES OF EXTERNAL
FIXATION
Dr BIPUL BORTHAKUR
PROF Orthopaedics, SILCHAR ,ASSAM,INDIA
INTRODUCTION
• EXTERNAL FIXATOR – COMPOSED OF BONE ANCHORAGE SYSTEM IN
THE FORM OF
• WIRES OR PINS
• ARTICULATIONS
• LONGITUDINAL OR RING SUPPORTS
• 2 BASIC TYPES
• PIN FIXATOR
• RING FIXATOR
PIN FIXATOR
• TYPES
• SIMPLE FIXATOR – PROVIDE INDEPENDENT APPLICATION OF SINGLE PINS
• CLAMP FIXATORS – PERMIT SPATIALLY CONSTRAINED PIN CLUSTERS
• CONFIGURATIONS
1. UNILATERAL
• 1 PLANE
• 2 PLANE
2. BILATERAL
• 1 PLANE
• 2 PLANE
MODULAR FRAME
• MODIFICATION OF THE UNILATERAL UNIPLANER FRAME
• 2 PINS IN EACH SEGMENT CONNECTED TO SHORT TUBE WITHG PIN-
TUBE CLAMP
• THIRD TUBE & TUBE-TUBE CLAMPS USED TO CONNECT SHORT TUBES
IN 2 BONE SEGMENTS
• ALL TUBES CAN BE ROTATED W.R.T EACH OTHER & FIXED IN ANY
RELATIVE POSITION
MODULAR FRAME
RING FIXATOR
• CONSIST OF COMPLETE OR PARTIAL RINGS CONNECTED BY RODS OR
ARTICULATED MEMBERS
• RINGS ARE ANCHORED TO BONE WITH
• HALF PINS
• HIGHLY TENSIONED WIRES (1.5-2 mm)
HYBRID EXTERNAL FIXATION
• COMBINE WIRE FIXATION AND PIN FIXATION
• USED FREQUENTLY FOR PROXIMAL OR DISTAL TIBIA FRACTURE WITH
• COMPROMISED SOFT TISSUE
• DIAPHYSEAL EXTENSION
• MINIMAL ARTICULAR COMMUNITION
HYBRID EX-FIX
GENERAL METHOD FOR HALF PIN FIXATORS
• SKIN INCISED
• SHARPLY
• SHORT LONGITUDINALLY
• ALONG SAFE ZONE
• BONE REACHED WITH GENTLE BLUNT DISSECTION
• DRILL SHEATH SHOULD BE USED DURING
• DRILLING
• TAPPING
• PIN INSERTION
• NEW DRILL BIT SHOULD BE USED WITH EACH PROCEDURE
• HAND DRILLING/LOW SPEED POWER DRILLING WITH PAUSE
• EX-FIX STIFFNESS INCREASES WITH AN INCREASE IN
• PIN NUMBER & DIAMETER
• PIN SEPARATION DIAMETER IN A BONE SEGMENT
• PIN INSERTION ANGLE
• ROD NUMBER & DIAMETER
• EX-FIX STIFFNESS DECREASES WITH INCREASE IN
• PIN SEPARATION DISTANCE ACROSS THE FRACTURE
• ROD-BONE DISTANCE
PIN-BONE INTERFACE STRESS REDUCING FACTORS
• PIN
• LARGE DIAMETER
• HIGH MODULUS MATERIAL
• MULTIPLE PIN CLUSTER
• REDUCED SPAN
• PRELOADING
• FIXATOR
• 2 PLANE CONSTRUCT
• PATIENT
• REDUCED WEIGHT BEARING
GENERAL METHODS FOR CIRCULAR WIRE
FIXATORS
• INCISION
• NOT REQUIRED FOR (1.5 & 1.8) mm WIRES
• REQUIRED -- >2mm WIRES & OLIVE WIRES
• LOW SPEED POWER DRILL WITH PAUSE OR HAND DRILL SHOULD BE
USED
• WIRE STABBED THROUGH SKIN & MUSCLE TO BONE
• WIRES DRIVEN ACROSS THE REMAINING SOFT TISSUES WITH A
MALLET AFTER CROSSING THE FAR CORTEX
• WIRES ARE FIXED TO EXTERNAL FRAME WITHOUT BENDING
• IF REQUIRED, SMALL SPACER CAN BE USED
• LARGE FRACTURE FRAGMENTS REQUIRE
• 2 LEVELS OF FIXATION
• 2 WIRES AT EACH LEVEL
• SHORT FRACTURE FRAGMENTS CAN BE FIXED WITH
• 1 RING & A DROP WIRE
• A WIRE OFFSET FROM THE MAIN RING BY A FEW cm
• STABILITY INCREASED BY INCREASEING THE ANGLE BETWEEN THE WIRES
• MINIMUM OF 3CM SKIN-RING GAP REQUIRED
FRACTURE HEALING IN EXTERNAL FIXATOR
• FAVOURS PERIOSTEAL HEALING
• A RIGID FRAME DELAYS HEALING
• LESS-RIGID FRAME PROMOTES HEALING
DYNAMIZATION
• EMBRACES BOTH APPOLICATION OF MICROMOVEMENT AND
LOADING TO THE FRACTURE SITE
• WITHOUT ANGULATION, ROTATION OR DISTRACTION
• PROMOTES FRACTURE HEALING
THANK YOU
• क्लैब्यं मा स्म गम: पार्थ नैतत्त्वय्युपपद्यते |
क्षुद्रं हृदयदौर्थल्यं त्यक्त्वोत्तिष्ठ परन्तप || 3||
• klaibyaṁ mā sma gamaḥ pārtha naitat tvayyupapadyate
kṣhudraṁ hṛidaya-daurbalyaṁ tyaktvottiṣhṭha parantapa
• Meaning-O Parth, it does not befit you to yield to this unmanliness.
Give up such petty weakness of heart and arise, O vanquisher of
enemies.

Principles of external fixation

  • 1.
    PRINCIPLES OF EXTERNAL FIXATION DrBIPUL BORTHAKUR PROF Orthopaedics, SILCHAR ,ASSAM,INDIA
  • 2.
    INTRODUCTION • EXTERNAL FIXATOR– COMPOSED OF BONE ANCHORAGE SYSTEM IN THE FORM OF • WIRES OR PINS • ARTICULATIONS • LONGITUDINAL OR RING SUPPORTS • 2 BASIC TYPES • PIN FIXATOR • RING FIXATOR
  • 4.
    PIN FIXATOR • TYPES •SIMPLE FIXATOR – PROVIDE INDEPENDENT APPLICATION OF SINGLE PINS • CLAMP FIXATORS – PERMIT SPATIALLY CONSTRAINED PIN CLUSTERS
  • 5.
    • CONFIGURATIONS 1. UNILATERAL •1 PLANE • 2 PLANE 2. BILATERAL • 1 PLANE • 2 PLANE
  • 7.
    MODULAR FRAME • MODIFICATIONOF THE UNILATERAL UNIPLANER FRAME • 2 PINS IN EACH SEGMENT CONNECTED TO SHORT TUBE WITHG PIN- TUBE CLAMP • THIRD TUBE & TUBE-TUBE CLAMPS USED TO CONNECT SHORT TUBES IN 2 BONE SEGMENTS • ALL TUBES CAN BE ROTATED W.R.T EACH OTHER & FIXED IN ANY RELATIVE POSITION
  • 8.
  • 9.
    RING FIXATOR • CONSISTOF COMPLETE OR PARTIAL RINGS CONNECTED BY RODS OR ARTICULATED MEMBERS • RINGS ARE ANCHORED TO BONE WITH • HALF PINS • HIGHLY TENSIONED WIRES (1.5-2 mm)
  • 10.
    HYBRID EXTERNAL FIXATION •COMBINE WIRE FIXATION AND PIN FIXATION • USED FREQUENTLY FOR PROXIMAL OR DISTAL TIBIA FRACTURE WITH • COMPROMISED SOFT TISSUE • DIAPHYSEAL EXTENSION • MINIMAL ARTICULAR COMMUNITION
  • 11.
  • 12.
    GENERAL METHOD FORHALF PIN FIXATORS • SKIN INCISED • SHARPLY • SHORT LONGITUDINALLY • ALONG SAFE ZONE • BONE REACHED WITH GENTLE BLUNT DISSECTION
  • 13.
    • DRILL SHEATHSHOULD BE USED DURING • DRILLING • TAPPING • PIN INSERTION • NEW DRILL BIT SHOULD BE USED WITH EACH PROCEDURE • HAND DRILLING/LOW SPEED POWER DRILLING WITH PAUSE
  • 14.
    • EX-FIX STIFFNESSINCREASES WITH AN INCREASE IN • PIN NUMBER & DIAMETER • PIN SEPARATION DIAMETER IN A BONE SEGMENT • PIN INSERTION ANGLE • ROD NUMBER & DIAMETER
  • 15.
    • EX-FIX STIFFNESSDECREASES WITH INCREASE IN • PIN SEPARATION DISTANCE ACROSS THE FRACTURE • ROD-BONE DISTANCE
  • 16.
    PIN-BONE INTERFACE STRESSREDUCING FACTORS • PIN • LARGE DIAMETER • HIGH MODULUS MATERIAL • MULTIPLE PIN CLUSTER • REDUCED SPAN • PRELOADING • FIXATOR • 2 PLANE CONSTRUCT • PATIENT • REDUCED WEIGHT BEARING
  • 17.
    GENERAL METHODS FORCIRCULAR WIRE FIXATORS • INCISION • NOT REQUIRED FOR (1.5 & 1.8) mm WIRES • REQUIRED -- >2mm WIRES & OLIVE WIRES • LOW SPEED POWER DRILL WITH PAUSE OR HAND DRILL SHOULD BE USED • WIRE STABBED THROUGH SKIN & MUSCLE TO BONE
  • 18.
    • WIRES DRIVENACROSS THE REMAINING SOFT TISSUES WITH A MALLET AFTER CROSSING THE FAR CORTEX • WIRES ARE FIXED TO EXTERNAL FRAME WITHOUT BENDING • IF REQUIRED, SMALL SPACER CAN BE USED
  • 19.
    • LARGE FRACTUREFRAGMENTS REQUIRE • 2 LEVELS OF FIXATION • 2 WIRES AT EACH LEVEL • SHORT FRACTURE FRAGMENTS CAN BE FIXED WITH • 1 RING & A DROP WIRE • A WIRE OFFSET FROM THE MAIN RING BY A FEW cm • STABILITY INCREASED BY INCREASEING THE ANGLE BETWEEN THE WIRES • MINIMUM OF 3CM SKIN-RING GAP REQUIRED
  • 20.
    FRACTURE HEALING INEXTERNAL FIXATOR • FAVOURS PERIOSTEAL HEALING • A RIGID FRAME DELAYS HEALING • LESS-RIGID FRAME PROMOTES HEALING
  • 21.
    DYNAMIZATION • EMBRACES BOTHAPPOLICATION OF MICROMOVEMENT AND LOADING TO THE FRACTURE SITE • WITHOUT ANGULATION, ROTATION OR DISTRACTION • PROMOTES FRACTURE HEALING
  • 22.
    THANK YOU • क्लैब्यंमा स्म गम: पार्थ नैतत्त्वय्युपपद्यते | क्षुद्रं हृदयदौर्थल्यं त्यक्त्वोत्तिष्ठ परन्तप || 3|| • klaibyaṁ mā sma gamaḥ pārtha naitat tvayyupapadyate kṣhudraṁ hṛidaya-daurbalyaṁ tyaktvottiṣhṭha parantapa • Meaning-O Parth, it does not befit you to yield to this unmanliness. Give up such petty weakness of heart and arise, O vanquisher of enemies.