BONE GRAFT SUBSTITUTES

DR. VISHAL THAKURSENIOR RESIDENT

DEPARTMENT OF ORTHOPAEDICSESIPGIMSR MGMH PAREL

BONE AS A TRANSPLANT TISSUE

MINERAL COMPONANT – STRUCTURAL INTEGRITY AND COMPRESSIVE STRENGTH

COLLAGENOUS MATRIX – TYPE I COLLAGEN AND NONCOLLAGENOUS MATRIX

GROWTH FACTOR COMPONANT – VARIOUS BONE MORPHOGENIC PROTEINS (5% OF THE BONE)

WHY ARE WE INTERESTED IN BONE GRAFT ALTERNATIVESBONE GRAFT MORBIDITY- 9% 1. PROLONGED WOUND DRAINAGE 2. HEMATOMAS 3. INFECTIONS 4. NERVE INJURY 5. PROLONGED PAINLARGER THE AMOUNT OF GRAFT MORE ARE THE

LIKELIHOOD OF COMPLICATIONSAUTOLOGUS BONE GRAFT IS NOT SUFFICIENT

IN SOME CASES LIKE BONE CYSTS, BONE DEFECTS, TUMORS ETC….

WHAT ARE THE ALTERNATIVES TO AUTOLOGOUS BONE GRAFTINGALLOGRAFTSDEMINERALIZED BONE MATRIX

(ENGINEERED ALLOGRAFTS)BONE MARROW INJECTIONS,

(OSTEOPROGENITOR CELLS)BMP INJECTIONS (OSTEOINDUCTOR)SYNTHETIC BONE GRAFTS

(OSTEOCONDUCTOR) 1. CORAL HYDROXYAPETITE 2.TRICALCIUM PHOSPHATES 3. CALSIUM SULFATE 4. COLLAGEN SUBSTRATES

ALLOGRAFTSAVAILABLE AS FRESH FROZEN FREEZE DRIED DEMINERALIZED PREDOMINANTLY IN TUMOR AND RECONSTRUCTIVE

HIP AND KNEE SURGERYPROBLEMS – HIGH PROCUREMENT COST CHANCES OF DISEASE TRANSMISSION (LESS

NOW) IMMUNE REJECTION PROBLEM ( LESS WITH DBM) INCONSISTANT INCORPORATION

( PREDOMINANLY OSTEOCONDUCTOR)

DEMINERALIZED BONE MATRIXOSTEOGENIC ACTIVITIES. USUALLY MIXED

WITH ALLOGRAFTPROBLEM – VERY SOLUBLE AND

DIFFICULT TO CONTAIN IN IMPLANTATION SITE.

GRAFTON – BASICALLY DBM AS GELOPTIFORM – DBM + COLLAGEN –

THERMOPLASTIC. AT BODY TEMPERATURE IT HARDENS TO THE CONSISTENCEY OF CANCELLOUS BONE

SYNTHETIC BONE GRAFT SUBSTITUTESENGINEERED MATRIX MATERIALENAHANCE FRACTURE HEALING WITH NO

MORBIDITY AND NO RISK OF DISEASE TRANSMISSION

MIXTURE OF OSTEOGENIC, OSTEOINDUCTOR AND OSTEOCONDUCTIVE INGRDIENT TO MIMIC AUTOLOGOUS BONE GRAFT

USUALLY MIXING COLLAGEN, MINERAL AND GROWTH FACTOR COMPONANT WITH OSTEOPROGENITOR CELLS.

CONDUCTIVE INDUCTIVE OSTEOGENIC

AUTOGENOUS BONE

+ + +

COLLAGEN +

CERAMIC +

MATRIX PROTEINS

+

BONE MARROW

+ +

CORAL HYROXYAPETITEINTERPORE, PRE OSTEONSOUTH SEA CORAL SKELETONS

CONVERTED TO PURE CRYSTALLINE HYDROXYAPETITE

POROUS STRUCTURE SIMILAR TO CANCELLOUS BONE

OSTEOCONDUCTIVESIGNIFICANT

INTERCONNECTIVITY TO FAVOUR FIBROVASCULAR INGROWTH

PROBLEM-1. MINIMAL REMODELLING DUE TO

HIGH CRYSTALLINE AND INSOLUBLE NATURE OF MATERIAL.

2. OSTEOCLAST CANNOT RESORB IT SO THESE MATERIALS WHEN USED LIVES INGRAFT BED FOR LIFE TIME

USEFUL IN CANCELLOUS BONES AS THEY PROVIDE IMMEDIATE SUPPORT AND RAPID INGROWTH AND HEALING OF CANCELLOUS BONES

NOT USEFUL IN DIAPHYSEAL FRACTURES WHERE STRUCTURAL INTEGRITY REQUIRED

MINERAL COMPOSITESSINTERED HA/TCP, CALSIUM SULPHATES,

NONCRYSTALLINE APETITES, BIOGLASSBIOGLASS AND NONCRYSTALLINE APETITIES

ARE INJECTED AS LIQUIDS WHICH HARDENS IN THE BONE SITE.

TCP, CALCIUM SULPHATES DISSOLVES RAPIDLY AND CREATE HIGH Ca/P SOLUBILITY PRODUCTS

THEY ARE OSTEOCONDUCTIVE, STRUCTURAL AND RESORBABLE

SINCE THEY ARE NONCRYSTALLINE THEY UNDERGO COMPLETE OSTEOCLAST RESORPTION

COLLAGENOSTEOCONDUCTIVEIDEAL SUBSTRATE FOR MINERAL

COMPOSITESBINDS TO CIRCULATING GROWTH

FACTORSENHANCES MINERAL CONTAINTS

OSTEOINDUCTIVITY

BONE MORPHOGENIC PROTEINSOSTEOINDUCTIVECOMMITS STEM

CELLS TO BECOME OSTEOPROGENITOR CELLS

ACTIVELY EXPRESSED IN FRACTURE CALLUS

TAKE HOME MESSAGEAUTOGRAFT IS GOLD STANDARD.GOOD SURGICAL SKILLS AND TISSUE

HANDLING IS VERY IMPORTANT IN OPERATIVE FRACTURE MANAGEMENT.

DO NOT HESITATE TO DO BONE GRAFT WHEN REQUIRED

VIGILANT TO DIAGNOSE NON UNION EARLY

STEM CELL RESEARCH IS UNDERWAY AND HAS PROMISING PROSPECTS.

THANK YOU….