Three-Dimensional Preoperative Planning Software and a Novel Information Transfer Technology Improve Glenoid Component Positioning

Abstract

Proper positioning of the glenoid component would be expected to improve the function and durability of the joint replacement.

Computer algorithms for three-dimensional measurement of humeral anatomy: analysis of 140 paired humeri

“…2,6,15,18,29 Therefore, deriving relevant geometric parameters such as humeral head retrotorsion, inclination, humeral length, and humeral head size can facilitate preoperative planning and accurate reconstruction during shoulder replacement surgery. 2,6,20,38 If 3D planning and computer-assisted surgery in total shoulder arthroplasty are desired, 8,10,17,21,28,33 methods for reproducible 3D quantification of the humeral anatomy are essential. We therefore developed computer algorithms for performing 3D measurements of the humeral anatomy and investigated bilateral differences of relevant geometric parameters, which can then play a role in inferring anatomic information for the pathologic side from the healthy side.…”

“…[25][26][27]31,34,35 In the last decade, the progress of this technology and its advantages have also been advocated in total shoulder arthroplasty. Improved accuracy of component positioning in the presence of osteoarthritis 8,17,21,28 or in the reconstruction of comminuted proximal humeral fractures 3 is probably a leading argument for the application of 3D preoperative planning and intraoperative navigation.…”

Surgical management of the biconcave (B2) glenoid

“…Additionally, this information can help the surgeon select the optimal implant to restore native glenoid anatomy, while avoiding peg perforation [7,26,27]. Patient specific instrumentation has been developed to help transfer information from the preoperative planning software to the patient [25]. P a t i e n t -s p e c i f i c in s t r u m e n t a t i o n i n s h o u l d e r arthroplasty involves creating a custom guide that references surface anatomy on the deformed glenoid.…”

Controversies in Shoulder Arthroplasty

“…First, there is no consensus on the degree to which glenoid retroversion should be corrected, and desired alignment must be determined at the time of surgery 39 ; however, new alignment guides are being developed that may improve intraoperative accuracy. [40][41][42][43][44] It is difficult to assess true glenoid augmentation performance if they are not accurately implanted. The complexities of the soft tissue environment are not fully understood, and the effectiveness and durability of augmented glenoid components in maintaining joint stability and preventing recurrent posterior subluxation, which has been shown in long-term follow-up studies of TSA with type B2 glenoids, 1 are still unknown.…”

“…When correctly placed, the patient's native premorbid version, inclination, and joint line can be determined and serve as references for selection of optimal implant type and location. 41,[50][51][52] 3D Templating, Planning Software, and Standard Instrumentation: From the preoperative plan, the location and orientation of the guide pin used for bone preparation and implant placement are defined within the software. The templated 3D images, along with the corresponding serial 2D images in 3 planes, oriented relative to the plane of the scapula, give a very accurate representation of the location of the guide pin and implant relative to the bony anatomy.…”