Sr Consultant & Joint Replacement Surgeon THE CEMENTED CUP Dr. Vivek Mittal Sr Consultant & Joint Replacement Surgeon DITO, New Delhi, India. www.drvivekmittal.com

6 decades ‘Gold Standard’ When we talk of cemented hip, we all remember Sir John Charnley. We salute him for giving us a successful implant and wonderful technique to implant it 6 decades ‘Gold Standard’

Cemented THR Results Minimum 10y F/up Study # F/u Rev (no’s) (yrs) (%) Fowler 1988 426 11 3.9 Ranawat 1988 50 10 2.0 Rieter 1992 238 10 4.6 These were the results 20 yrs back, but are good by any standard

Cemented THR Results 18 – 20 yrs F/up Study # F/u Rev (no’s) (yrs) (%) Wroblewski 1993 193 18 3.0 Shulte 1993 332 20 4.0 & these results after 20 yrs implantation, excellent, but remember 2 factors: all of these guys are masters in craftsmanship, & Charnley 1 had better results

Cemented Sockets - Younger Pts 10 yr survival Ballard, Johnston -78% JBJS 1994 Cornell, Ranawat -90% JBJS 1986 Sullivan, Johnston -90% Sedel -90% However in young & active individuals the revision rates were unacceptable from 10 to 22%

Survivorship of Cemented vs Uncemented Cup Age Group 10 yrs 15 yrs 20 yrs 90 77 69 95 81 - 87 97 91 96 98 55 - 64 65 - 74 > 75 Finnish Registry Data JBJS 2008

Current Trends: Region Based Swedish Hip Registry 2008 Australian Jt Registry 2009

CEMENT = Polymer + Monomer (powder) (liquid) Catalyst Only a grouting agent – No adhesive property / Reduces high stress concentration Strong in Compression Weak in tension / shear Factors affecting Cement Bone Stock – Adequate Cementing Technique – Appropriate Dry surface Pressurization of cement Uniform cement mantle of 2-3mm What is cement?

CEMENT = Polymer + Monomer (powder) (liquid) Catalyst Factors affecting Cement Bone Stock – Adequate Environment : Room Temp / Moisture Mixing Technique Additives What is cement? Clinically altered Mixing time Working time Setting time

Appro. Cement Technique Aim: To achieve highly durable Macro / micro interlock into cortico – cancellous bone Cement – Bone Interface Preserve - Cancellous Bone Maximize Area – Multiple Drill Holes Dry & Clean Bone – Pulse Lavage + Hypotensive Anesthesia Cementing Technique Cement Insert - before blood contamination Low viscosity & pressurize (1.5mts) Prosthesis - insert slowly & Maintain pressure until cement cured

Radiographic Classification Type 1 Homogenous No radiolucency Type 2 Incomplete Type 3 Complete radiolucency in > 1 zone Type 1 Homogenous No radiolucency Type 1 Homogenous No radiolucency Type 2 Incomplete

Conclusion Team dependant rather Individual dependent (Surgeon / Associates / Nurse / Anesthetist) Difficult to achieve consistency in cementing Technique is Crucial Bloodless Field Pressurization of cement 2-3 mm uniform cement mantle 33f 1987 52f 2008