ORTO: 45, 46, 47, 48 Flashcards
LIMITS OF FRACTURE GAPS
THOSE APPROACHING THE DIAMETER OF THE BONE SHOULD BE AVOIDED
STRAIN
DECREASE IN GAP WIDTH/TOTAL WIDTH
STRAIN IS GREATER IN SMALLER FRACTURE GAPS
ES: 1 MM FG, 1 MM MOTION=100% STRAIN
GRANULATION TISSUE CAN SUPPORT UP TO 100% STRAIN
STRESS PROTECTION
LIMITING STRAIN TO 1-2% SHOULD BE AVOIDED BECAUSE THERE IS NOT ENOUGH MECHANICAL SIGN TO CELLS OF THE CALLUS
BIOLOGIC FACTORS OF BONE HEALING
TISSUE GROWTH FACTORS + CELLS (MESENCHYMAL STEM CELL)
DELAYED UNION, DEFINITION
PROLONGATION IN TIME FOR FRACTURE HEALING
MECHANICAL CAUSES OF DELAYED UNION
- EXCESSIVE FRACTURE GAPS
- MOTION AT THE FRACTURE SITE
BIOLOGIC CAUSES OF DELAYED UNION
- INTRINSIC (FACTOR OF PATIENT AND FRACTURE, MOST COMMON)
- EXTRINSIC
- BOTH
AVOID DELAYED UNION
- PREEMPTIVE AUTOGENOUS CANCELLOUS BONE, BONO MORPHOGENETIC PROTEINS, DEMINERALIZED BONE MATRIX
- AVOID LARGE FRACTURE GAPS
NONUNION
- VIABLE NONUNIONS (HORSE’S FOOT)
- NONVIABLE UNIONS (BIOLOGICALLY INACTIVE)
MALUNION
- HEALING HAS OCCURRED
- FAILURE OF MECHANICAL REESTABLISHMENT OF THE FORM AND FUNCTION OF THE FRACTURE
HOW TO DEFINE A DEFORMITY
IN RELATIONSHIP OF THE DISTAL SEGMENT TO THE PROXIMAL SEGMENT
MECHANICAL AXE BONE
LINE CONNECTING CENTER POINTS PROXIMAL AND DISTAL TO THE BONE IN FRONTAL OR SAGGITAL PLANE
ANATOMIC AXE
FOLLOWS GEOMETRY OF THE BONE: LINE THAT PASSES TROUGH THE CENTER OR MID DIAPHISIS
JOINT ORIENTATION ANGLE
- FIRS LETTER: M or A, MECHANICAL OR ANATOMIC AXIS
- SECON LETTER: CR or CD (angle on saggital images) ; M or L (angle on frontal planes)
- THIRD LETTER: P or D: proximal or distal
- FOURTH LETTER: letter for the bone
LABRADORS MEAN RADIUS ANGLE
- FRONTAL
aMPRA 83 aLDRA 86
- SAGGITAL
aCdPRA 85 aCdDRA 77 PROCURVATUM 27
FEMURAL ANGLE
- ANATOMIC labradors
aLDFA 97 aLPFA 103
- MECHANICAL
mLDFA 100 mLPFA 100
FEMORAL ANTEVERSION ANGLE
- Nunamaker AXIAL 27
- montavon Oblique 31.3
- dudley axial+CT 16 19.6
PALEY’S RULE
- osteotomy and angulation correction axis (ACA) CORA based correct
- osteotomy non correct, ACA correct → appropriate realignment through angulation and TRANSLATION
- osteotomy and ACA non correct → traslation iatrogenic
MOST COMMON BACTERIA ISOLATED OSTEOMYELITIS DOG
- STAPHYLOCOCCUS SPP. (60%)
- ESCHERICHIA COLI
- STREPTOCOCCUS
STAPH. PSEUDOINTERMEDIUS, METHICILLYN RESISTANT UP 50% → MOST COMMON RECENT STUDIES
BACTERIAL BIOFILM FUNCTIONS
- ALTERED-QUIESCENT BACTERIAL GROWTH PATTERN (ANTIBACTERIALS RELY ON BACTERIAL GROWTH SO DIMINISHED EFFECT)
- BARRIER
- ANTIMICROBIAL ACTIVITY (HYDRATION LEVEL, LOW PO2, HIGH PCO2, LOW PH)
RADIOGRAPHIC OSTEOMYELITIS
62.5% SENSIBILITY, 57% SENSITIVITY
RADIOGRAPHIC OSTEOMYELITIS
- SEQUESTRUM
- LUCENCY AROUND IMPLANTS AND INVOLUCRUM (PERIOSTEAL PROLIFERATION9
- CLOACA (DRAINING TRACT)
SURGICAL TREATEMENT FOR OSTEOMYELITIS
- REMOVAL NECROTIC TISSUE, SEQUESTRA, FOREIGN MATERIAL
- METICOLOUS DEBRIDEMENT
- BIOFILM REMOVAL DISRUPTION
PRATESI 2015, ORTHO POST-OP INFECTION
- OVERALL 12,9%
- 21.3% WITH POST-OP ANTIBIOTIC TREATEMENT
- 4.3% WITHOUT POST-OP ANTIBIOTIC TREATEMENT
FREY 2010, CCL POST-OP INFECTION
OVERALL 6.1%
- ECLS surgeries 4.2%, TPLO surgeries 8.4%
- suture material other (3,9%) than stainless-steel staples (7,7%) for skin closure
- postoperative oral administration of antimicrobials (10,7 % VS 5,1%)
surgical wound to become infected
critical amount of contamination (> 105 organisms/g of tissue) is required
4 MECHANISM OF NEW BONE FORMATION
- OSTEOGENESIS: SUPPLIES BONE-FORMING CELLS
- OSTEOINDUCTION: MATERIALS THAT INDUCE BONE FORMATION (RECTUITS MESENCH. CELLS)
- OSTEOCONDUCTION: SCAFFOLD TO MESENCHIMAL CELLS
- OSTEOPROMOTION: ENHANCEMENT ON REGENERATING BONE; NO CELL (ES. PRP)
GOLD STANDARD FOR BONE GRAFT
CANCELLOUS AUTOGENOUS BONE GRAFT
OSTEOGENESIS, OSTEOINDUCTIVE, OSTEOCONDUCTION AND OSTEOPROMOTIVE FUNCTION
COMMON DONOR SITE FOR AUTOGENOUS CANCELLOUS BONE GRAFT
- PROXIMAL REGION HUMERUS
- ILIAC WING
- PROXIMOMEDIAL TIBIA
- SUBTROCANTERIC FEMUR
- CONDYLES FEMUR
- CAUDOVENTRAL PORTION MANDIBLE
TIME TO REPEAT BONE GRAFTING
8 WEEKS HUMERUS, 12 WEEKS PROXIMAL TIBIA
HOW TO HARVEST CANCELLOUS BONE AUTOGRAFT
CURETTAGE AFTER HOLE (KIRSCHNER) IN THE DESIRED LOCATION
ALLOGRAFT-BASED BONE GRAFT: PROPERTIES?
- OSTEOINDUCTIVE
- OSTEOCONDUCTIVE
- NO OSTEOGENIC CELLS PRESENT
MAY BE COMBINED WITH PRP OR OTHER GROWTH FACTORS TO HAVE OSTEOPROMOTIVE FEATURES
CORTICAL ALLOGRAFT
ONLY STRUCTURAL SUPPORT. CREEPING SUBSTITUTION OCCURS AS THEY SLOWLY GET SUBSTITUTED WITH HOST BONE
CALCIUM PERCENTAGE IN DEMINERALIZED BONE MATRIX TO ENHANCE OSSEOUS WOUND HEALING
LESS 2%. BECAUSE PROCESS OF OSTEOINDUCTION OCCURS IMMEDIATELY WITHOUT REABSORPTION PRIOR TO FORMATION OF NEW BONE
