Delayed Union & Nonunion of Fractures

Post on 16-Jul-2015

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Transcript of Delayed Union & Nonunion of Fractures

Dr. Armaan Singh

Delayed UnionThe exact time when a given fracture should be united cannot be defined

Union is delayed when healing has not advanced at the average rate for the location and type of fracture(Between 3-6 months)

NonunionFDA defined nonunion as “established when a minimum of 9 months has elapsed since fracture with no visible progressive signs of healing for 3 months”

Every fracture has its own timetable (long bone shaft fracture 6 months, femoral neck fracture 3 months)

Delayed/Nonunion

Factors contributing :

Systemic

Local

Systemic factorsNutritional status- MalnutritionMetabolic - Diabetes (neurovascular)Smoking Tobacco and alcohol useGeneral healthActivity levelUse of NSAIDs (have been found to decrease fracture healing in multiple animal studies)

THE LITERATURE IS STILL CONFLICTING CONCERNING THE INFLUENCE OF NSAIDS ON FRACTURE HEALING

Local factorsFracture characteristics-OpenInfectedsegmentalComminuted by severe trauma

Anatomic Location of Fractures

Soft tissue injuryTraumaticIatrogenicTreatment relatedInsecure fixationInsufficient immobilizationFixation in distractionIrradiated bone

ClassificationBased on viability of the bone ends

1. Hypervascular non-unions

2. Avascular nonunion

Hypervascular or Hypertrophic:

1. Elephant foot (hypertrophic, rich in callus)

2. Horse foot (mildly hypertrophic, poor in callus)

3. Oligotrophic (not hypertrophic, no callus)

Avascular or Atrophic

Torsion wedge (intermediate fragment)

Comminuted (necrotic intermediate fragment)

Defect (loss of fragment)

Atrophic (scar tissue with no osteogenic potential)

Treatment1. Electrical

2. Electro-magnetic

3. Ultrasound

4. Surgical

PREVENTION IS ALWAYS BETTER THAN CURE

General Treatment principals

Vast number of surgical and nonsurgical methods available but….

Rarely - one method successful .Simplest, most easily tolerated.Should allow potential use of other methods

Bone Grafting Autogenous cancellous bone remains the “gold

standard” in grafting material

Other options

allograft bone

synthetic bone substitute

Vascularised bone grafting

Low intensty ultrasound

Theories

stimulates the genes involved in inflammation and bone regeneration.

increases blood flow through dilation of capillaries and enhancement of angiogenesis, increasing the flow of nutrients to the fracture site.

chondrocyte stimulation is enhanced, which leads to an increase in enchondral bone formation.

PROTOCOL IS TO USE THE ULTRASOUND EQUIPMENT FOR 20 MINUTES ONCE A DAY

Electrical and electromagnetic stimulation.

Bone growth stimulators - used in conjunction.

External electrical stimulation -advantageous in infected nonunion.

EXTERNAL ELECTRICAL STIMULATION IS ESPECIALLY ADVANTAGEOUS IN INFECTED NONUNION MANAGEMENT OR WHEN SURGICAL INTERVENTION IS CONTRAINDICATED

Considerations before Surgery Status of Soft Tissues and Neurovascular Structures –Unyielding scar tissues, Deep scarring may prevent bone transport or grafting.

Soft-tissue contractures must be considered

Status of Bones Hypertrophic (hypervascular) non-unionsstable fixation.

Atrophic (avascular) non-unions decortication and bone grafting

Consideration to the factors responsible for non or delayed union is desired before

proceeding to further treatment

Reduction of FragmentsThe fragments are mobilized, preserving their normal soft-tissue attachments as much as possible.

Extensive dissection is avoided, resecting only the scar tissue and the rounded ends of the bones so that contact is maximal

Medullary canals are cleared of fibrous tissue to aid in medullary osteogenesis and they are apposed

Stabilization of fragments.Adequate stabilization obtained by -

Plates and screws.

Intra-medullary nails.

External fixation.

Provide sufficient stability – without excessive

rigidity.

External FixationAdvantage–

relatively noninvasive and does not disturb soft tissues surrounding the nonunion.

ability to correct deformity and provide stable fixation.

The Ilizarov external fixator is very effective, tool in the treatment of non-unions.

Surgical guidelinesGood reductionBone graftingFirm stabilization

biomechanical stability and

biological vitality of the bone.