Upload
vodang
View
221
Download
0
Embed Size (px)
Citation preview
© Zimmer July 28, 2014 Page 1
Zimmer® Patient Specific
Instruments (PSI) for
Reverse Shoulder Arthroplasty
Ryan Krupp, M.D.
Norton Orthopaedic Specialists
Louisville, KY
Anand Murthi, M.D.
MedStar Union Memorial Hospital
Baltimore, MD
Zimmer® Patient Specific
Instruments (PSI) for
Reverse Shoulder Arthroplasty:
Rationale and Overview
Anand Murthi, M.D.
MedStar Union Memorial Hospital
Baltimore, MD
Goals of Reverse Shoulder
Arthroplasty
• Pain relief
• Function restoration
• Stability
• Durability
© Zimmer July 28, 2014 Page 2
Complications in Reverse Shoulder
Arthroplasty
• Radiolucencies*
• Instability*
• Infection
• Glenoid loosening*
• Hematoma
• Humerus fracture (in op)
• Acromio/Scap fracture * Directly
influenced by glenoid placement
(Boileau P, Old J, Pinedo M, Zumstein MA. Problems, complications, reoperations, and
revisions in reverse total shoulder arthroplasty: a systematic review . J Shoulder Elbow
Surg. 2011 Jan;20(1):146-57.)
Glenoid Component Malposition
• Common challenges– Glenoid bone loss, erosion and deformity
– Lack of visibility; challenging exposure
– Lack of reference; scapula movement
• Resulting difficulties– Pre-operative definition of pre-morbid anatomy
– Defining the optimal implant and its location
– Executing the surgery, bone preparation and implant placement
• Potential complications– Dislocation
– Loosening
– Notching
– Excessive poly wear
Glenoid Pathology - Value of 3D Imaging
• Assess version
• Assess OA posterior/inferior bone loss
• Assess CTA superior/central bone loss
• Assess revision cavitary bone loss
• X-rays and 2D imaging have many
problems with inaccurate assessment(Hoenecke HR Jr, Hermida JC, Flores-Hernandez C, D'Lima DD. Accuracy of CT-based
measurements of glenoid version for total shoulder arthroplasty. J Shoulder Elbow Surg.
2010 Mar;19(2):166-71.)
© Zimmer July 28, 2014 Page 3
Longevity of a total and
reverse shoulder prosthesis
largely depends on correct
positioning and fixation of
the glenoid component.
Positioning• Location of the center (AP and SI dimensions)
• Location of joint line: avoiding medialization
• Version, inclination and rotation angles
• Post placement within glenoid vault
Fixation
• Support bone preservation
• Baseplate contact area
• Maximal screw length
• Bi-cortical purchase
• Avoidance of critical structures
• Focus on Reverse Shoulder Arthroplasty (RSA) due to:
– Addressing potential RSA
complication rates
– Increasing demand for RSA
procedures
– RSA patient population trending younger
Zimmer PSI Shoulder
• Goal of Zimmer PSI Shoulder:
– Improve accuracy of positioning and fixation of glenoid baseplate
– Maximize performance
Cleveland Clinic Results
Effect of PSI for Achieving Desired Location of the Glenoid Component 31 Pts RCT
(Note: This PSI study conducted with non-Zimmer glenoid components, primary TSA)
(Michael D. Hendel, MD, PhD; Jason A. Bryan, MS; Wael K. Barsoum, MD; Eric J. Rodriguez, BS; John J. Brems, MD; Peter J. Evans,
MD, PhD; Joseph P. Iannotti, MD, PhD. Comparison of Patient-Specif ic Instruments w ith Standard Surgical Instruments in Determining
Glenoid Component Position: A Randomized Prospective Clinical Trial. J Bone Joint Surg Am, 2012 Dec 05;94(23):2167-2175.)
© Zimmer July 28, 2014 Page 4
• Zimmer PSI demonstrated to reduce variability in
baseplate component and
screw placement for RSA
– Base plate accuracy better
than 5°of variation to plan
for both inclination/version (69% PSI vs. 29% Non-PSI)
– Screws placed within 7°of
variation to plan compared to the non-PSI technique
(88% PSI vs. 22% Non-PSI)
Cadaveric Study Results
Aggregate analysis of cadaver studies on Zimmer f ile including 29 shoulders
using Zimmer PSI (TR-TG120709-01 Warsaw Cadaveric Lab 2012 and TR-
FB121026-01 Chicago PSI Shoulder Cadaver Lab November 2012).
Element One: 3D Planning SoftwareElement Two:
PSI Bone Model
Element Three:
Patient Specific Instrument Guides
Three Elements of Solution
CT Scan
1
Surgeon Plan
2
PSI Guides
3
Quality
4
Recovery
85 7
SurgerySterilizationShipping
5 6
PSI Shoulder Process
© Zimmer July 28, 2014 Page 5
Preoperative Planning Overview
Zimmer® Patient Specific
Instruments (PSI) for
Reverse Shoulder Arthroplasty:
Surgical Technique
Ryan Krupp, M.D.
Norton Orthopaedic Specialists
Louisville, KY
PSI Shoulder Pre-op Report:
Baseplate Planned Position
Baseplate Sagittal View Baseplate Transverse View
© Zimmer July 28, 2014 Page 6
PSI Shoulder Pre-op Report:
Glenoid Reaming
Glenoid Reamed Surface Sagittal View
Baseplate Post Length: 15mm
PSI Shoulder Pre-op Report:
Fixation Screw Length
Screw Insertion Anterior View Screw Insertion Coronal View
PSI Shoulder Instrument Guides
Roll Guide
Screw GuideReam Guide
Pin Guide
© Zimmer July 28, 2014 Page 7
Intraoperative Video
Zimmer® Patient Specific
Instruments (PSI) for
Reverse Shoulder Arthroplasty:
Case Study
Anand Murthi, M.D.
MedStar Union Memorial Hospital
Baltimore, MD
PSI Shoulder Case Review
• 75 y.o. female chronic right shoulder
pain
• Pseudoparalysis
• VAS = 9
• Left RSA 1 year ago doing well
• Right stage 4 CTA
© Zimmer July 28, 2014 Page 15
PSI Shoulder Surgery
Zimmer® Patient Specific
Instruments (PSI) for
Reverse Shoulder Arthroplasty:
Case Study
Ryan Krupp, M.D.
Norton Orthopaedic Specialists
Louisville, KY
60 Y/O RHD FEMALE
H/O POLIO > 50 YRS
SEVERE OSTEOPOROSIS
SEVERE PAIN AND WEAKNESS
LEFT REVERSE TSA 2011
FE 60/ER 20/IR LB
3/5 STRENGTH
© Zimmer July 28, 2014 Page 19
Transverse view, superior part of baseplate
Measure = 4.46 mm
Sagittal view at contact area
with the base plateSagittal view of the 3D model