Basic concept of fracture healing

1. FRACTURE HEALING
BY
Dr VAITHILINGAM RAMAIYAH
VIGNESH

2. NICHOLAS
ANDRY
•COINED THE TERM
ORTHOPAEDICS
•ORTHO MEANS
CORRECT OR
STRAIGHT
•PAEDICS MEANS
CHILD

3. BONE FRACTURE DEFINITION
• MEDICAL CONDITION - DAMAGE IN
CONTINUITY OF THE BONE

4. FEATURES
• HEALING OF BONE FRACTURE IS SIMILAR TO
HEALING OF SOFT TISSUE WOUND
• HEALING ONSET OCCURS ONCE BONE IS
FRACTURED AND IT CONTINUES TILL LIFE AS
REMODELLING
• COMMONLY IMMOBILIZATION IS NECESSARY
FOR HEALING,FEW EXCEPTIONS- FRACTURE RIB.

5. • NOT MANDATORY FOR SURGEON TO IMPOSE
IMMOBILITY FOR BONE FRACTURE, NATURE CAN
DO SO BY CALLUS FORMATION IN RESPONSE TO
MICROMOVEMENT.
• MOST FRACTURES ARE SPLINTED, NOT TO ENSURE
UNION BUT TO ALLEVIATE PAIN,& TO ENSURE
THAT UNION TAKES PLACE IN GOOD POSITION
AND PERMIT EARLY MOVEMENT OF LIMB .
• PROCESS OF FRACTURE REPAIR VARIES
ACCORDING TO TYPE OF BONE INVOLVED AND
AMOUNT OF MOVEMENT AT FRACTURE SITE

6. JEAN-ANDRE
VENEL
ESTABLISHED
FIRST
ORTHOPEDIC
INSTITTUTE IN
1780

7. HEALING OF CORTICAL BONE
FRACTURE
• HEALING BY CALLUS FORMATION -NATURAL
FORM OF HEALING,IN ABSENCE OF RIGID
FIXATION.
• 5 STAGES, THEY ARE STAGES OF
• HEAMATOMA FORMATION
• GRANULATION TISSUE FORMATION
• CALLUS FORMATION
• CONSOLIDATION
• REMODELLING

9. STAGE OF HAEMATOMA FORMATION
• LASTS UPTO 1 WEEK
• BETWEEN AND AROUND FRACTURE SITE
• ISCHAEMIC NECROSIS - FRACTURE ENDS
• PERIOSTEUM AND LOCAL SOFT TISSUE STRIPS
FROM FRACTURE ENDS
• SOME OSTEOCYTES DIES AND OTHERS ARE
SENSITIZED TO RESPOND SUBSEQUENTLY BY
DIFFERENTIATING INTO DAUGHTER CELLS
WHICH CONTRIBUTE TO HEALING PROCESS

10. STAGE OF GRANULATION TISSUE
• FROM 2ND TO 3RD WEEK
• SENSITIZED PERCURSORS CELLS PRODUCE CELLS WHICH
DIFFERENTIATE AND ORGANIZE TO PROVIDE BLOOD
VESSELS,FIBROBLAST,OSTEOBLASTS ETC.
• COLLECTIVELY THEY FORM A SOFT GRANULATION
TISSUE IN THE SPACE BETWEEN FRACTURE FRAGMENT
• THIS CELLULAR TISSUE EVENTUALLY GIVES A SOFT
TISSUE ANCHORAGE TO FRACTURE,WITHOUT ANY
STRUCTURAL RIGIDITY

11. • FRACTURED SITE-STILL MOBILE
• FROM THIS STAGE,HEALING OF BONE DIFFERS
FROM THAT OF SOFT TISSUE
• i.e., IN SOFT TISSUE HEALING ,THE
GRANULATION TISSUE IS REPLACED BY
FIBROUS TISSUE
• IN BONE HEALING THE GRANULATION TISSUE
FURTHER DIFFERENTIATES TO CREATE
OESTEOBLAST WHICH SUBSEQUENTLY FORM
BONE

12. STAGES OF CALLUS FORMATION
• USUALLY 4 TO 12 WEEKS
• GRANULATION TISSUE DIFFERENTIATES FURTHER AND
CREATES OSTEOBLASTS
• THESE CELLS LAY DOWN AN INTERCELLULAR MATRIX
WHICH SOON BECOMES IMPREGNATED WITH
CALCUIM SALTS.(MINERALIZATION OF GRANULATION
TISSUE)
• RESULTS IN FORMATION OF CALLUS ,ALSO CALLED
WOVEN BONE(WHICH IS RADIOLOGICALLY VISIBLE)

13. • CALLUS IS 1 ST SIGN OF UNION ON
X –RAY,USUALLY 3 WEEKS AFTER FRACTURE.
• FORMATION OF THIS BRIDGE OF WOVEN BONE
IMPARTS GOOD STRENGTH TO FRACTURE
• CALLUS FORMATION IS SLOWER IN ADULT THAN
IN CHILDREN AND IN CORTICAL BONE THAN IN
CANCELLOUS BONE.
• FRACTURE CLINICALLY UNITED,AND IT IS NO
MORE MOBILE.

14. STAGE OF CONSOLIDATION
• WOVEN BONE IS REPLACED BY MATURE BONE WITH
TYPICAL LAMELLAR STRUCTURE
• THIS PROCESS OF CHANGE IS MULTICELLULAR UNIT
BASED,WHEREAS A POCKET OF CALLUS IS REPLACED BY A
POCKET OF LAMELLAR BONE.
• IT IS SLOW PROCESS AND EXTEND ANYTHING FROM ONE
TO FOUR YEARS.
• IN THIS STAGE OUTLINE OF CALLUS BECOMES DENSE AND
SHARPLY DEFINED.

15. STAGE OF REMODELLING
• FRACTURED BONE WILL BEGRADUALLY STRENGTHENED.
• SHAPENING OF CORTICES OCCURS AT ENDOSTEAL AND PERIOSTEAL
SURFACE ,SO THAT FRACTURE SITE BECOME INDISTINGUISHABLE
FROM PARENT BONE.
• MAJOR STIMULUS COMES FROM LOCAL BONE STRAIN i.e., WEIGHT
BEARING STRESSES AND MUSCLE FORCES WHEN PERSON RESUMES
ACTIVITY.
• THIS STAGE IS MORE CONSPICUOUS IN CHILDREN WITH
ANGULATED FRACTURE
• OCCURS TO A VERY LIMITED EXTENT IN FRACTURE IN ADULT

16. ANTONIUS
MATHYSEN
INVENTED
PLASTER OF
PARIS ,A
DUCTCH
MILITARY
SURGEON
1851

17. HEALING OF CANCELLOUS BONE
• FOLLOW DIFFERENT PATTERN
• BONE IS UNIFORM SPONGY TEXTURE AND HAS NO
MEDULLARY CAVITY,SO THAT THERE IS A LARGE AREA OF
CONTACT BETWEEN THE TRABECULAE.
• UNION CAN OCCUR DIRECTLY BETWEEN THE BONE
SURFACE WITHOUT HAVING TO PASS THROUGH THE
STAGES OF CALLUS FORMATION.
• FOLLOWING HEAMATOMA AND GRANULATION
FORMATION,MATURE OSTEOBLAST LAY DOWN WOVEN
BONE IN INTRACELLULAR MATRIX ,AND THE TWO
FRAGEMENT THUS UNITES.

18. HEALING BY DIRECT UNION
• CLINICAL AND EXPERIMENTAL STUDIES HAVE SHOWN CALLUS
FORMATION OCCURS DUE TO MOVEMENT AT FRACTURE SITE.
• THEY SERVE TO STABILIZE FRAGEMENTS AS RAPIDLY AS POSSIBLE –
A NECESSARY PRECONDITION FOR BRIDGING BY BONE.
• IF FRACTURED BONE IS ABSOLUTELY IMMOBILE , STIMULUS FOR
CALLUS FORMATION WILL NOT BE PRESENT
Eg., 1.IMPACTED FRACTURE IN CANCELLOUS BONE,
2.FRACTURE RIGIDLY IMMOBILIZED BY METAL PLATE.
• SO OSTEOBLASTIC NEW BONE FORMATION OCCURS DIRECTLY
BETWEEN THE FRAGMENTS.

20. • GAPS BETWEEN THE FRACTURES ARE INVOLVED BY NEW
CAPILLARIES &OSTEOPROGENITORS CELLS GROWING IN FROM THE
EDGES & NEW BONE IS LAID DOWN ON EXPOSED SURFACE (GAP
HEALING).
• WHERE CREVICES ARE VERY NARROW (< 200
MICRONS),OSTEOGENESIS PRODUCES LAMELLAR BONE,WIDER
GAPS ARE FILLED FIRST BY WOVEN BONE,WHICH IS THEN
REMODELLED TO LAMELLAR BONE.
• IN 3-4 WEEKS ,FRACTURE IS SOLID ENOUGH TO ALLOW
PENETRATION AND BRIDGING OF AREA BY BONE REMODELLING
UNITS,i.e.,OSTEOCLASTIC (CUTTING CONES)FOLLOWED BY
OSTEOBLAST.
• WHERE THE EXPOSED FRACTURE ARE IN INTIMATE CONTACT AND
HELD RIGIDLY FROM OUTSIDE ,INTERNAL BRIDGING MAY
OCCASIONALLY OCCUR WITHOUT ANY INTERMEDIATE
STAGES(CONTACT HEALING).

21. • HEALING BY CALLUS FORMATION,THOUGH LESS DIRECT
(THE TERM INDIRECT COULD BE USED)HAS DISTINCT
ADVANTAGES.IT ENSURES MECHANICAL STRENGTH
WHILE BONE ENDS HEAL AND WITH INCREASING
STRESS THE CALLUS GROWS STRONGER AND
STRONGER (AN EXAMPLE OF WOLFF’S LAW).
• WITH RIGID METAL FIXATION i.e., IN THE ABSENCE OF
CALLUS FORMATION ,THERE IS A LONG PERIOD
DURING WHICH THE BONE DEPENDS ENTIRELY UPON
THE METAL IMPLANT FOR ITS INTERGRITY.
• MOREOVER THE IMPLANT DIVERTS STRESS AWAY
FROM BONE,WHICH BECOME OSTEOPOROTIC AND
NOT RECOVER FULLY UNTIL METAL IS REMOVED.

22. HIPPOCRATES
EXPLAINED ABOUT
CORRECTION OF
SHOULDER
DISPLACEMENT

23. FACTORS INFLUENCING FRACTURE
HEALING
• AGE
• SEX
• TYPE OF BONE
• PATTERN OF FRACTURE
• DISTURBANCE DUE TO PATHOANATOMY
• TYPE OF REDUCTION
• IMMOBILISATION
• COMPRESSION OF FRACTURE SITE
• ELECTRICAL STIMULATION
• COMPOUNDING

24. UNION ,CONSOLIDATION,NON-UNION
• REPAIR OF FRACTURE IS A CONTINUOUS PROCESS,ANY
STAGES INTO WHICH IT IS DIVIDED ARE NECESSARILY
ARBITRARY.
• UNION:-IS AN INCOMPLETE REPAIR WHERE ENSHEATHING
CALLUS IS CALCIFIED.CLINICALLY FRACTURE SITE WILL BE
LITTLE TENDER AND THOUGH THE BONE MOVES IN ONE
PIECE (AND IN THAT SENSE IS UNITED),ATTEMPTED
ANGULATION IS PAINFUL.
• X-RAY SHOWS THE FRACTURE LINE STILL CLEARLY
VISIBLE,WITH FLUFFY CALLUS AROUND IT.
• REPAIR IS INCOMPLETE AND IT IS SAFE TO SUBJECT THE
UNPROCTED BONE TO STRESS.

25. CONSOLIDATION
• COMPLETE REPAIR,WHERE CALCIFIED CALLUS IS
OSSIFIED,CLINICALLY FRACTURE SITE IS NOT
TENDER,NO MOVEMENT CAN BE OBTAINED AND
ATTEMPTED ANGULATION IS PAINLESS.
• X-RAY SHOWS FRACTURE LINE TO BE ALMOST
OBLITERATED AND CROSSED BY BONE
TRABECULAE,WITH WELL DEFINED CALLUS AROUND IT.
• REPAIR IS COMPLETE AND FURTHER PROTECTION IS
UNNECCESSARY.

26. NON UNION
• SOMETIMES THE NORMAL PROCESS OF FRACTURE REPAIR IS
THWARTED AND BONE FAILS TO UNITE.
• CAUSES:-
1. DISTRACTION AND SEPARATION OF FRAGMENTS
2. INTERPOSITION OF SOFT TISSUES BETWEEN FRAGMENTS
3. EXCESSIVE MOVEMENT AT FRACTURE LINE
4. SEVERE INJURY THAT RENDER LOCAL TISSUE NON VIABLE OR
NEARLY SO
5. POOR LOCAL BLOOD SUPPLY
6. INFECTION
7. SURGERY, IF ILL JUDGED

27. • NON UNION CAN BE ASEPTIC OR SEPTIC
• ASEPTIC NON UNION CAN EITHER BE STIFF OR MOBILE AS
JUDGED BY CLINICAL EXAMINATION
• MOBILE NON UNION CAN BE FREE AND PAINLESS TO GIVE
IMPREESION OF FALSE JOINT(PSEUDOARTHROSIS)
• ON X-RAYS- NON UNION ARE TYPICAL
• BY PRESENCE OF A LUCENT LINE BETWEEN BONE
FRAGMENTS
• SOMETIMES THERE IS EXUBERANT CALLUS TRYING BUT
FAILING-TO BRIDGE THE GAP(HYPERTROPHIC NON-
UNION)OR AT TIMES NONE AT ALL (ATROPHIC NON-UNION)

29. BONE MORPHOGENETIC PROTEIN
• GROUP OF GROWTH FACTORS AND AS
METABOLOGENS
• INDUCE BONE AND CARTILAGE FORMATION
• RHBMP-2 AND RHBMP-7 ARE FDA APPROVED
• USED IN SPINAL FUSION,NONUNION,AND ORAL SX
• CONTRAINDICATED ANTERIOR CERVICAL DISCECTOMY
AND FUSION

30. BIBLIOGRAPHY
• APLEY’S SYSTEM OF ORTHOPAEDICS &
FRACTURES
• CAMPBELL’S OPERATIVE ORTHOPAEDICS
• ROCKWOOD AND GREEN’S FRACTURES IN
ADULTS
• ESSENTIALS OF ORTHOPAEDICS –RM SHENOY
• ESSENTIAL ORTHOPAEDICS –J.MAHESHWARI