pmma

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

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THANK YOU.