the knee society | virtual fellowship AWS
THE KNEE SOCIETY | VIRTUAL FELLOWSHIP CHAPTER I2 “ARTICULATION AND CONSTRAINTS”
Cruciate Retaining Designs Presented by: Jeremy Ross, MD; Christopher E. Pelt, MD; Jill Erickson, PA-C; Mike B. Anderson MSc; Christopher L. Peters, MD COPYRIGHT © 2016 THE KNEE SOCIETY
POSTERIOR CRUCIATE RETAINING TKA Outline Introduction Potential Advantages of CR TKA Indications for CR TKA Surgical technique
“Balancing” the PCL Anterior stabilized vs. posterior stabilized Clinical results COPYRIGHT © 2016 THE KNEE SOCIETY
PCL FUNCTION IN THE NATIVE KNEE Limits posterior tibial translation
Drives femoral rollback on the tibia Moves contact point more posterior Increases lever arm of extensor mechanism
by 30% Small contribution to internal, external, and
varus/valgus constraint COPYRIGHT © 2016 THE KNEE SOCIETY
POTENTIAL ADVANTAGES OF CR TKA Improved femoral rollback Lack of patellofemoral clunk associated with some PS designs
Less bearing constraint Allows more component rotation Potential for more pre-surgical knee kinematics Preservation of femoral bone stock – no box cut Improved survivorship in registry studies COPYRIGHT © 2016 THE KNEE SOCIETY
INDICATIONS FOR CR TKA End-stage knee osteoarthritis Flexion contracture 90 degrees Coronal plane deformity PS Mayo registry – 8117 TKAs (5389 CR and 2728 PS) examined for 15-year
survivorship CR – 90% survival PS – 77% survival UK National Joint Registry 2015 CR knees have lower risk of revision Holds true for cemented and uncemented/hybrid applications
Australian registry PS>CR revision rate
COPYRIGHT © 2016 THE KNEE SOCIETY
CLINICAL RESULTS Author(s) (Year)
Implant
Mean follow-up
Survivorship
Whiteside (2001)
PCL-retained
15-18 years
96.1%
Sextro et al (2001)
PCL-retained
15 years
85.1%
Dixon et al (2005)
PCL-retained
15 years
92.6%
Gill and Joshi (2001)
PCL-retained
16.8 years
96%
Schwartz et al (2010)
PCL-retained
10 years
97.7%
Rasquinha et al (2006)
Posterior-stabilized
12 years
94.6%
Tang et al (2004)
Posterior-stabilized
7.8 years
94%
Lee et al (2011)
Posterior-stabilized
7 years
98%
Pavone et al (2001)
Posterior-stabilized
23 years
91%
COPYRIGHT © 2016 THE KNEE SOCIETY
THANK YOU
Cruciate Retaining Designs Presented by: Jeremy Ross, MD; Christopher E. Pelt, MD; Jill Erickson, PA-C; Mike B. Anderson MSc; Christopher L. Peters, MD COPYRIGHT © 2016 THE KNEE SOCIETY
POSTERIOR CRUCIATE RETAINING TKA Outline Introduction Potential Advantages of CR TKA Indications for CR TKA Surgical technique
“Balancing” the PCL Anterior stabilized vs. posterior stabilized Clinical results COPYRIGHT © 2016 THE KNEE SOCIETY
PCL FUNCTION IN THE NATIVE KNEE Limits posterior tibial translation
Drives femoral rollback on the tibia Moves contact point more posterior Increases lever arm of extensor mechanism
by 30% Small contribution to internal, external, and
varus/valgus constraint COPYRIGHT © 2016 THE KNEE SOCIETY
POTENTIAL ADVANTAGES OF CR TKA Improved femoral rollback Lack of patellofemoral clunk associated with some PS designs
Less bearing constraint Allows more component rotation Potential for more pre-surgical knee kinematics Preservation of femoral bone stock – no box cut Improved survivorship in registry studies COPYRIGHT © 2016 THE KNEE SOCIETY
INDICATIONS FOR CR TKA End-stage knee osteoarthritis Flexion contracture 90 degrees Coronal plane deformity PS Mayo registry – 8117 TKAs (5389 CR and 2728 PS) examined for 15-year
survivorship CR – 90% survival PS – 77% survival UK National Joint Registry 2015 CR knees have lower risk of revision Holds true for cemented and uncemented/hybrid applications
Australian registry PS>CR revision rate
COPYRIGHT © 2016 THE KNEE SOCIETY
CLINICAL RESULTS Author(s) (Year)
Implant
Mean follow-up
Survivorship
Whiteside (2001)
PCL-retained
15-18 years
96.1%
Sextro et al (2001)
PCL-retained
15 years
85.1%
Dixon et al (2005)
PCL-retained
15 years
92.6%
Gill and Joshi (2001)
PCL-retained
16.8 years
96%
Schwartz et al (2010)
PCL-retained
10 years
97.7%
Rasquinha et al (2006)
Posterior-stabilized
12 years
94.6%
Tang et al (2004)
Posterior-stabilized
7.8 years
94%
Lee et al (2011)
Posterior-stabilized
7 years
98%
Pavone et al (2001)
Posterior-stabilized
23 years
91%
COPYRIGHT © 2016 THE KNEE SOCIETY
THANK YOU
