AAOS 2009 - RESTORIS® MCK MultiCompartmental Knee System

RESTORIS ® MCK
MultiCompartmental Knee System
Thomas M. Coon, M.D.

Prevalence of Osteoarthritis (OA)
Unicompartmental tibiofemoral OA is
estimated at 10% 1
Patellofemoral OA is estimated
around 24% 1,2
40-65% of OA patients present with
tibiofemoral-patellofemoral disease 1,2,3
RESTORIS ® MCK-bone-conserving
treatment options for unicompartmental
and bicompartmental disease
1 Duncan R, Hay E, Saklatvala J, Croft P. Prevalence of radiographic osteoarthritis: it all depends on your point of view. Rheumatology 2006;45:757-60.
2 Ledingham J, Regan M, Jones A, Doherty M. Rediographic patterns and associations of osteoarthritis of the knee in patients referred to hospital. Annals of the Reeumatic
Diseases 1993;52:520-526.
3 Rolston L, Sprague J, Tsai S, Salehi A. A novel bone/ligament sparing posthesis for the treatment of patellofemoral and medial compartment osteoarthristis. AAOS 2006 Annual
Meeting, Poster #P181.

The Argument for Bicompartmental
Arthroplasty
Conserves ligaments and bone
Less loss of proprioception
May increase patient satisfaction
Recovery between UKA and TKA

System Requirements of RIO
Enabled Design
Anatomically shaped
Wide range of sizes
Bi-cruciate retaining
Fixed bearing
Modular components for
compartment disease
Modular implants for size
interchangeability
Minimal incision
Bone prep using TGS system
Cemented
Articular
Surface Design
Multicompartmental
Modularity
Fixation Surfaces

Articular Surface Design
Implant geometry based on quantitative mapping of 121
femurs & 115 tibias in 55 healthy, 50 OA and (balance)
cadaver knees.

Articular Surface Design
Implant geometry based on quantitative mapping of 121
femurs & 115 tibias in 55 healthy, 50 OA and (balance)
cadaver knees.
Male Female
C1 – 100-01-0011
Size 1 Size 1
C1 – 100-01-0031
Size 3 Size 3
C1 – 100-01-0048
Size 1 Size 2
C1 – 100-01-0037
Size 3 Size 5
C1 – 100-01-0030
Size 3 Size 3
C1 – 100-01-0035
Size 4 Size 6

RESTORIS ® MCK MultiCompartmental
Knee System: Design Philosophy
Sculpt the anatomy
Preserving bone offers less traumatic
interventions as OA progresses
Implant should fit the anatomy
Design for bicompartmental disease
Nest components to enable optimal fit &
smooth patella transition
Target the patient-specific knee
Specificity at just the gender level assumes
all women are created equal

Customized Fit with Off-the Shelf
Components

Fixation Surfaces
Fully contoured anatomic surfaces to permit minimum
bone removal.
Peripheral edges, posts and keels permit entire bony
resection with a single cutting tool.

Robotically Optimized Implants

Articular Surface Design
Study of tibial
plateaus across
size range shows
a lower aspect
ratio would better
fit the tibial plateau
than many current
UNI components,
especially in larger
sizes.
ML (mm)
Baseplate Aspect Ratio
36
34
32
30
28
26
24
22
20
35 40 45 50 55 60
AP (mm)

Excellent bone fit and ligament
balance

Anatomic Reconstruction

I Planned a UKA-Now What

MCK Bicompartmental Knee

MCK Bicompartmental Knee

Summary
New tools enable novel approaches
MultiCompartmental Knee system is:
designed to address the early
spectrum of DJD from single-
to multi-compartmental resurfacing.
based upon extensive anatomic
data in healthy AND arthritic knees.
based upon extensive use of FEA
and dynamic mechanical modeling
tools and cadaver laboratory experience.
C1 – 100-01-0035
Size 4 Size 6

The End