Design of Patient Specific Guides (PSG) for Reverse Shoulder Arthroplasty

Completed

• Conditions: Proximal Humeral Fracture
• Interventions: Device: PSG

• Registration Number: NCT06611059
• Lead Sponsor: Fundació Institut de Recerca de l'Hospital de la Santa Creu i Sant Pau

Brief Summary

This is a two steps observational study

In the first part we will compare the accuracy of the commercial guide against a in-hospital designed patient specific guide. As a secondary goal, the problems detected during the design phase will be described.

Once the accuracy of the guide is acceptable, we will implant the glenosphere of future patients using the PSG guide following the same engineering design process.

Detailed Description

Reverse shoulder arthroplasty is a treatment for both non-synthesizable fractures and arthropathy degenerative. This implant is based on two main components: glenosphere and stem. The stem in turn is integrated in its upper part by a polyethylene that reduces the friction torque between the glenosphere and the stem.

Correct positioning of the glenosphere is critical for functionality and survival of the implant. Malpositioning of glenosphere can be related to:

In recent years, given the

* The scapula is a flat bone, without any reference axis;

* Surgical approaches expose only the glenoid cavity, with few bone landmarks;

* The humerus and deltoid make access to the glenoid difficult;

* The morphology of the scapula is very variable.

Preoperative planning even without PSG improves the positioning accuracy of the guide in the glenoid. In glenoids with only a slight deformity, PSGs improve the accuracy of the guide entry point (\<1 mm error, compared to \> 4 mm under visual control) and orientation (\< 3◦ error compared to \> 7◦). In glenoids with more significant deformities, planning also showed superiority.

Study Timeline

• Study Start: 2023-04-01
• Study First Submitted: 2023-12-19
• Primary Completion: 2024-01-23
• Study Completion: 2024-01-23
• Study First Submitted QC: 2024-09-23
• Study First Posted: 2024-09-24
• Status Verified: 2024-11
• Last Update Submitted: 2024-11-04
• Last Update Posted: 2024-11-06

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 11

Inclusion Criteria

• Patient with proximal humerus fracture candidate for reversed shoulder arthroplasty
• Patient with degenerative arthropathy candidate for reversed shoulder arthroplasty

Exclusion Criteria

• Previous surgeries on the proximal humerus or glenoid
• No desire to participate in the study
• Lack of ability to accept the study (tutored patients)
• Open fractures

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Arm && Interventions

Group	Intervention	Description
in-hospital designed patient specific guide	PSG	-

Primary Outcome Measures

Name	Time	Method
Difference in glenoid center	months	Difference in glenoid center (mm): distance between the points of entry on the surface of the scapula, the planned center versus the finally drawn
Glenoid version deviation (α)	months	Glenoid version deviation (α): defined as the angle between the real trajectory of the drilling and the scapular anatomical plane, projected about the axis of neutral inclination (defined as that which goes from the center of the glenoid to the trigonum spinae).
Glenoid inclination deviation (β)	months	Glenoid inclination deviation (β): defined as the angle between the actual milling path and the plane of the neutral tilt axis, projected on the SP axis

Trial Locations

Locations (1)

Hospital de la Santa Creu i Sant Pau; 🇪🇸 Barcelona, Spain