One technique for replacing the articular surface of the patella in total knee replacement is the use of a cementless porous-coated metal-backed polyethylene component. Anteroposterior, lateral, and Merchant or skyline radiographs in 10 cases of porous-coated metal-backed components that failed were evaluated for component alignment, component displacement, radiolucencies, loose beads, and integrity of the patellar component. Component failure was documented by surgery in all 10 cases. Seven cases of failure involved the patellar pegs or junction of the pegs with the metal backing and three cases involved the polyethylene portion. In the seven cases of peg-metal backing failure, three cases showed loose beads before failure and seven cases showed displacement of the metal backing at time of failure. All three cases of polyethylene failure showed narrowing or displacement of the polyethylene portion. Our experience shows that displacement of the metal backing, displacement of the polyethylene, and disruption of patellar pegs are seen in failed porous-coated metal-backed patellar components. Loose beads may be seen before peg-metal backing failure.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.2214/ajr.155.3.2117356 | DOI Listing |
J Long Term Eff Med Implants
October 2020
Hansjörg Wyss Hip and Pelvis Center, Swedish Medical Center, Seattle, WA.
Acetabular underreaming is a bone preservation and fixation strategy in hip resurfacing. Prior reports of acetabular component deformation have been cadaveric studies. In this study, I sought to determine deformation of thin shells and very thin highly cross-linked polyethylene in patients, the effects of increasing underreaming and liner-head clearance, and whether deformation accelerates wear.
View Article and Find Full Text PDFJ Orthop Sci
January 2013
Department of Orthopaedics and Trauma, Royal Infirmary of Edinburgh, Edinburgh EH16 4SA, UK.
Background: The reported survivorship of total shoulder replacement (TSR) is variable. This is probably related to implant design. We report the outcome and survivorship of the uncemented glenoid in patients with osteoarthritis receiving a TSR with an intact or repairable rotator cuff at surgery.
View Article and Find Full Text PDFActa Orthop
August 2011
Washburn University, Topeka, KS , USA.
Background: It is unclear whether there is a clinical benefit to adding hydroxyapatite (HA) coatings to total knee implants, especially with the tibial component, where failure of the implant more often occurs. A systematic review of the literature was undertaken to identify all prospective randomized trials for determining whether the overall clinical results (as a function of durability, function, and adverse events) favored HA-coated tibial components.
Methods: A comprehensive literature search was performed for the years 1990 to September 16, 2010.
J Shoulder Elbow Surg
July 2010
Shoulder Unit, Department of Orthopaedics and Trauma, Sunderland Royal Hospital, Sunderland, United Kingdom.
Hypothesis: We believe the variable reported survivorship of the metal-backed glenoid is related to the design of the component. This study reports the outcome and survivorship of the uncemented glenoid in rheumatoid patients with an intact or repairable rotator cuff at surgery, and considers the key design features that may predict longevity of this component.
Method: Forty-six shoulders in 39 patients (31 women), with a mean age of 55 years (range, 35-86 years) received a total shoulder replacement with a screw-fixed porous coated metal-back glenoid.
Acta Orthop Belg
April 2009
Department of Orthopaedic Surgery, University Hospital Pellenberg, Leuven, Belgium.
Between 1991 and 2003, the senior author performed 42 bilateral total hip arthroplasties as a single-stage procedure in 21 patients less than 35 years old. One patient was lost to follow-up, leaving 40 total hip arthroplasties in 11 male and 9 female patients for review, with a mean follow-up of 9.7 years (5-17 years).
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!