Name: Improvements in Glenoid Fixation
Uploaded: 2016-12-21T00:00:00Z
Channel: Arthrex
Description: Evan S. Lederman, MD, (Phoenix, AZ) reviews the clinical history of glenoid fixation and discusses the Univers VaultLock™ Glenoid System design rationale and technique.

<p>Evan S. Lederman, MD, (Phoenix, AZ) reviews the clinical history of glenoid fixation and discusses the Univers VaultLock™ Glenoid System design rationale and technique.</p>

Not Hidden

English  - en

video

VPT1-00623-EN | A | Improvements in Glenoid Fixation

Evan S. Lederman

Human

A video of a live presentation reviewing Arthrex products or techniques.

Video einer Live-Präsentation, die Arthrex Produkte oder Techniken überprüft.

Präsentationsvideos

Presentation Videos

Vídeo de apresentação ao vivo analisando produtos ou técnicas da Arthrex.

Apresentação vídeos

Video de presentación en vivo que revisa los productos o técnicas de Arthrex.

Video presentaciones

Improvements in Glenoid Fixation

We know the total shoulder arthroplasty outcome is favorable to Hemiarthroplasty with regards to patient satisfaction, range of motion, and overall revision rates over long term follow up, and the survivorship of total shoulder replacement is also favorable at 15 years, with significant better long term results with the all polyethylene glenoid over uncemented or metal backed glenoid. The problem, however, is that sometimes when we do an uncomplicated total shoulder and get a reasonable post-operative x ray that sometimes several years later we'll see subsidence of the glenoid component, loss of the subchondral bone, and migration of the component, and osteolysis. And in the same patient showing an arthroscopic view, the glenoid can be loose and there's complete loss of the subchondral bone support and a cavitary lesion that can develop in the glenoid. When looking at Achilles glenoid over the long term, we see progressive radiologic loosening over time, and radiologic loosening lines progressed significantly up to 90% at nine years, and in a large study of almost 4000 patients, the annualized rate of asymptomatic loosening is 7%. Symptomatic loosening of 1.2%, and the overall revision rate of approximately 1% per year in the Australian registry. When looking at cemented glenoid components versus uncemented glowing components, the revision rate is approximately 1% per year and significantly less than the metal back components and the Uncemented components. And similarly in the New Zealand registry. Can you advance the slide, please? In the New Zealand registry, they found almost a five time increase in revision rates of metal back components as opposed to cemented components. Additionally, when looking at Uncemented hemiarthroplasty, there's virtually no radiolucency around the humerus or osteolysis. But when you add a glenoid component, there's a significant component of polyethylene disease felt to be related to related to glenoid loosening or polyethylene wear, and in long term studies, 15 to 20 years. We also see progressive radiolucent lines develop over time, which does lead to increased revision rates over time, which is fairly intuitive. And when looking at peg versus keeled components in a meta analysis, for the most part the Peg component is favored with regards to radiolucency loosening and revision rates over the glenoid component, and this is mostly American literature and the Australian registry. When looking at the peg versus the keel components, they have similar long term revision rates of about 1%, but a small favorable trend towards the Peg components in fairly mid-term follow up. In an effort to try to improve glenoid fixation, other manufacturers have developed what's called the fluted peg in this particular design. These papers are based upon the same component. In Churchill's paper, they looked at placing this fluted glenoid component with just peripheral cement and worse study. They used peripheral cement as well as bone grafting around the central peg. And in the study they used just bone graft and no cement at all. And in all cases, they did see some bone growth. Bone growth and osseointegration around the flutes of the peg. And that bone growth and osseointegration showed less radiolucent lines and loosening over time. And in Arnold's study, they looked at the presence of the osteo integration around the peg and found that when there was better osteo integration, there was less radiolucent lines around the rest of the glenoid, and with less integration there was more radiolucent lines. And probably the most interesting study, Nuttall and Trail did a radio stereometric analysis, where they found that six of the 11 had fairly poor osteo integration around their central peg, and postulated the lack of initial fixation led to early glenoid component migration and failure, leading other authors to try to find better solutions for fixation in a different fluted peg component. They placed this with bone graft around the central peg and CeMend peripherally, and found that they had good osseointegration over time, and it was didn't matter whether it was a type A or a type B glenoid, and showed favorable results with minimal revisions related to the to the glenoid. The effect of reaming has been looked at in this interesting study from Jos. Walsh. They found that glenoid survival was 98% at ten years for their cemented glenoid, but radiographic signs of loosening were minimal at five years, but between 5 to 10 years went up almost 50%. And when they looked at the different groups of patients in the study, they found that if there was aggressive reaming that led to increased rates of subsidence in glenoid component migration, and they recommended or stated that there was a concerning rate of radiographic loosening that only became apparent after five years and was associated with excessive reaming. In an effort to try to decrease the reaming, they studied the radius of curvature of the glenoid utilizing a spherical fit model with CT scans, and identified that the radius of curvature of the glenoid and the arthritic glenoid did vary, and that if the glenoid radius of curvature was smaller than the size of the reamer, then the peripheral bone would be weakened with reaming, and if the glenoid radius curvature was larger than the reamer, then the central bone would be weakened with reaming. So what's the next big thing? Big thing in the glenoid? Well, this is the Arthrex. Univers VaultLock glenoid, which is a next generation fluted peg component. The goals of design were to improve the initial stability, to allow for better osseointegration, and to limit reaming to support the subchondral bone, and the characteristics include a fluted central post, but there's also a fluted superior peg and working off the existing peg model. The flutes were slightly enlarged on the lower keel peg as well. We also studied the radius curvature of the glenoid utilizing a direct measurement model in the formula shown here, and found also a variation in the radius of curvature, similar to the Walsh study. But then when we did linear regression analysis, looking at both CT scans, MRI scans and arthritic and non arthritic glenoid, we found that there was a direct relationship between the size of the glenoid and the radius of curvature, which is fairly intuitive. So the Univers VaultLock design has a variable backside radius of curvature where the radius gets larger with the larger side of the glenoid. So there's one size for each size of glenoid. But based upon this data. This is a sawbones of the technique for placing the VaultLock glenoid. The guide pin can be placed either using a guide or with the virtual implant system guides that are available. The goal here is minimal reaming. The Nautilus Reamers, which were introduced last year, are a half moon reamer that are shaped with this progressive radius of curvature. The novel thing about these is by their design, they push the retractors out of the way so you never have to remove your tractors when you're reaming. And then we complete our central peg, similar to the original peg design, and remove our guide pin at that point in time. The preparation for the peg is the same as the existing Peg design, and the superior hole is drilled in. The drill bit is left in place to act as a derotation peg, and then three small drill holes are drilled sequentially inferiorly to complete the lower pegged part of the glenoid. The guides are then removed and the preparation is completed with a punch that finishes the lower peg by connecting the dots. And there's also an additional accessory device to enlarge that if need be. We do recommend placing a trial to make sure that you have good, complete backside coverage, and that the rim surface matches at the back of the implant and it seats completely. Now for insertion we recommend cement on the proximal and distal pegs and bone grafting of the central peg. We feel that the design of the implant will lead to some additional stability. And for those of you who have used a fluted peg design, it also offers that very, very acceptable tactile feel of a glenoid that locks in place once it's seated all the way, and it's very sturdy from its initial fixation. The system also involves a next generation glenoid prep system that Nick talked about extensively with the pre-operative planning. Multiple options for guide pin placement, including a standard guide, a version corrected guide, or the IRI and smart bone options. For the insertion technique, we do recommend taking autograft from the humeral head when available, or any type of allograft that you wish to use. If the humeral head is not available, there's a crimping tool to pinch the bone into the flutes of the prosthesis, which allows the bone graft to really nicely interdigitate into the flutes, and then the peripheral holes are cemented. This is a cadaver model showing that once it's seated, you get nice penetration of the bone graft within the flutes, and it integrates in there nicely. And the technique is recommended to use proper guide pin placement utilizing the VIP system, a limited reaming technique respecting the radius of curvature of the glenoid bone. Grafting the central pegs in a limited cement proximally and distally. The VaultLock rounds out the anatomic total shoulder replacement system from Arthrex, utilizing the in vivo, in vivo inclination inversion adjustment that the universe two and the apex stems offer the subscapularis repair technique. We have the pegged and keeled standard components and the eccentric humeral heads.

Improvements in Glenoid Fixation

Páginas Relacionadas

Artroplastia do ombro

Sistema glenoidal Univers VaultLock^®

Produto

Artroplastia do ombro

Sistema total de ombro Univers™ Apex

Produto

Artroplastia do ombro

Sistema de ombro total Univers™ II

Produto

Improvements in Glenoid Fixation

Páginas Relacionadas

Artroplastia do ombro

Sistema glenoidal Univers VaultLock®

Produto

Artroplastia do ombro

Sistema total de ombro Univers™ Apex

Produto

Artroplastia do ombro

Sistema de ombro total Univers™ II

Produto

Sistema glenoidal Univers VaultLock^®