Tornier Perform Anatomic Augmented Glenoid Implants correct posterior subluxation and maintain active joint reduction in Walch B2 glenoids
Bibliographic record
Abstract
BACKGROUND: The Walch type B2 glenoid is characterized by retroversion, posteroinferior erosion and posterior humeral head subluxation. A surgical management option for a B2 glenoid is an anatomic total shoulder arthroplasty (aTSA) with a posteriorly augmented all-posterior augmented glenoid (PAG) implant. However, little is known about what occurs actively at the glenohumeral articulation after aTSA with a PAG. Additionally, most studies on B2 glenoids, whether pre-aTSA or post-aTSA, assess subluxation statically. Presently, it is unknown if subluxation recurs after aTSA with a PAG or if it varies dynamically throughout active motion. Therefore, the primary objective of this study was to determine if Walch type B2 patients managed with an aTSA and a PAG (Tornier Perform Anatomic Augmented Glenoid Implant) would maintain correction of subluxation when examined statically and when stressed with active motion. The secondary objective was to analyze if a patient's range of motion (good or limited), magnitude of B2, or PAG implant size (15° or 25°) affect postoperative correction of subluxation. METHODS: Twenty Walch type B2 patients (mean age 68 years, range 54-83) underwent stemless aTSA with a 15° or 25° PAG implant and were assessed at a minimum 2-year follow-up. All patients underwent dynamic four-dimensional computed tomography scanning to actively track glenohumeral implant alignment and subluxation during a provocative active internal rotation (IR) motion protocol. Bone and implant 3D models of the humerus and scapula for each four-dimensional computed tomography scan were created using 3D Slicer. Landmarks were selected on the models to create coordinate systems that were then used in conjunction with a custom program (MATLAB) to determine subluxation preoperatively (statically), and postoperatively (dynamically). RESULTS: Posterior humeral head subluxation was significantly corrected (P < .001) from an average of 66% (range 51%-98%) preoperatively to 54% (range 41%-77%) postoperatively. Concentric aTSA joint alignment was maintained throughout an active IR motion protocol, as subluxation percentage only varied by 1% throughout IR movement (range 54%-55%). Neither patient IR range of motion (good or limited) nor size of PAG (15° or 25°) had a significant effect (P > .05) on subluxation postoperatively. CONCLUSION: At short-term follow-up, aTSA with an all-polyethylene PAG (Tornier Perform Anatomic Augmented Glenoid Implant) was successful at restoring and maintaining glenohumeral alignment with correction of subluxation throughout a provocative active IR motion protocol. As such, recurrence of subluxation does not occur statically or actively in patients who have undergone glenoid reconstruction with correction of posteroinferior erosion with a half-wedge PAG implant. Thus, aTSA with a PAG implant is an acceptable option for patients with mild or moderate B2 glenoids.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.003 | 0.001 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".