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MODERATOR---PROF P.U.MALLYA
CO-MODERATOR---DR.RONALD M.
PRESENTATION BY DR.RAMESH.R
POLY METHYLMETHACRYLATE
HISTORY : 1st Acrylic acid created - 1843.
Methacrylic acid formulated - 1865
German chemist “Fitting & Poul” discovered the
polymerization process -1877
First Cemented total hip replacement-Haboush
Sir John Charnley - acrylic fixation for implants-
1960
Clear transparent liquid
Melting point 48°C
Boiling point 100.8°C
Excellent organic solvent
METHYL METHACRYLATE MONOMER
Not a glue
Space filling, load transferring material
relatively brittle solid.
Properties vary as brands
BIO MECHANICAL PROPERTIES:-
Sterile liquid.
Powder component.
TWO COMPONENTS
Colorless flammable liquid.
Major component - methyl methacrylate monomer
Hydroquinone:
N- N Dimethyl P- toludine ;
LIQUID COMPONENT
Composed of PMMA based polymer.
Benzoyl peroxide;
Barium sulphate ;
Zirconium dioxide
POWDER COMPONENTS
Dough time:i.e 2-3min
Working time; 5-8min
Setting time: 8-10min
Recommended mixing temperature ; 23℃
3 CHARACTERISTIC TIMES.
More rapid mixing dough time.
Room temperature dough & setting
time
FACTORS WHICH AFFCT
Humidity setting time
Avoid formation of pores and voids . TWO
methods.
Vacuum mixing : Centrifugation;
Contd….
Antibiotics in powdered form , heat stable ,
appropriate spectrum of antibacterial coverage
ANTIBIOTICS ADDED TO CEMENT
Aminoglycosides most commonly used
Pencillins,Cephalosporins,Clindamycin are
eluted well. Vancomycin elutes much less.
contd….
Not Used
FLUROQUINOLONES,,
TETRACYCLINE
POLYMIXIN-B
Contd….
Introduced onto the prepared femoral canal still
in low viscous phase.
Introduced in a retrograde manner under
pressure with the help of cement gun or syringe.
Blood not allowed to mix while setting.
PRINCIPLES FOLLOWED
GUN & SYRINGE
1.Arthroplasty in
Rheumatoid arthritis , Osteo arthritis, Traumatic
arthritis, Osteoporosis, Avascular Necrosis,
Collagen disease.
INDICATIONS:
2. Severe joint destruction secondary to trauma
or other conditions.
3. Revision arthroplasty
4. Pathological fractures of shaft of humerus &
femur.
5. Obliteration of bone cavities
Contd….
6. Chronic osteomyelitis
7. Artificial maxillo facial implants and dental
materials.
8. Hard contact lenses
Continue….
1.Transitory fall in Blood pressure
2.Elevated serum GGTP
3.Thrombophlebitis
4.Loosening or displacement of the prosthesis
5.Superficial or deep wound infection
6.Trochantric bursitis
7.cardiac conduction irregularities
COMMON ADVERSE EFFECTS
Myocardial infarction.
Cardiac arrest.
Pulmonary embolism.
Anaphylaxis.
SERIOUS ADVERSE EFFECTS;
Hypoxemia.
Cardiac arrhythmia.
Bronchospasm.
Pyrexia due to allergy to the bone cement.
Hematuria.
Dysuria.
OTHERS
Bladder fistula.
Local neuropathy.
Local vascular erosion and occlusion.
Transitory worsening of pain due to heat
released during polymerization.
Contd…
Active or incompletely treated infection .
Hyper sensitivity to any of the cement
components.
First 3rd of pregnancy .
CONTRA INDICATIONS
Campbell`s operative orthopaedics-vol 1 Tenth edition
Turek`s orthopaedics-vol 1,Fourth edition Rock wood&Green; Fracture in Adults vol
1,Sixth edition JBJS(Am)1983 65A,575-578 Complications in
arthroplasty JBJS(Am)2008 Addition of antibiotics to cement
REFERENCES
…..
THANK YOU.