Dr. Armaan Singh
Jul 16, 2015
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.