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We describe our experience with a new system of patient-specific template called Personal Fit(®), which is unique in shoulder surgery and used in combination with Duocentric(®) prosthesis. The reverse prosthesis's concept is the invention of Paul Grammont, developed with Grammont's team of Dijon University as from 1981, which led to the first rever...
Context in source publication
Context 1
... protocol that is sent to the radiologist; upload of digital image files onto a secure external server; three-dimensional reconstruction of the joint by Aston Medical. 4. Surgeon receives email notification that the planning can be performed. 5. Planning for glenoid component (Fig. 17): on the screen, the surgeon can see a glenoid baseplate in the ''zero'' position, which corresponds to the center of the baseplate being superimposed over the center of the native glenoid ( Fig. 6) and with zero degrees of inclination and retroversion; the user can successively change the size of the glenoid baseplate and the length of ...
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Background
The reverse shoulder arthroplasty (RSA) may be a promising alternative for proximal humerus tumours because of good postoperative shoulder function. However, the conventional reverse shoulder prosthesis can not meet individual needs and RSA has been associated with a relatively high complication rate. Therefore, implant design and surgic...
Citations
... It is known that excessive implant retroversion of the glenoid baseplate is the cause of early loosening and failure, 14,20,42,48 and that accurate correction of moderate to severe glenoid retroversion is difficult. 22 Furthermore, malpositioning of the baseplate in the superior/inferior plane increases the risk of scapular notching, as this impacts on peg glenoid rim distance and sphere bone overhang distance. ...
Hypothesis:
Glenoid baseplate positioning for reverse total shoulder arthroplasty (rTSA) is important for stability and longevity, with techniques such as image-derived instrumentation (IDI) developed for improving implant placement accuracy. We performed a single-blinded randomized controlled trial comparing glenoid baseplate insertion accuracy with 3D preoperative planning and IDI jigs vs. 3D preoperative planning and conventional instrumentation.
Methods:
All patients had a preoperative 3D computed tomography to create an IDI; then underwent rTSA according to their randomized method. Repeat computed tomography scans performed at six weeks postoperatively were compared to the preoperative plan to assess for accuracy of implantation. Patient-reported outcome measures and plain radiographs were collected with 2-year follow-up.
Results:
Forty-seven rTSA patients were included (IDI n = 24, conventional instrumentation n = 23). The IDI group was more likely to have a guidewire placement within 2mm of the preoperative plan in the superior/inferior plane (P = .01); and exhibited a smaller degree of error when the native glenoid retroversion was >10° (P = .047). There was no difference in patient-reported outcome measures or other radiographic parameters between the two groups.
Conclusion:
IDI is an accurate method for glenoid guidewire and component placement in rTSA, particularly in the superior/inferior plane and in glenoids with native retroversion >10°, when compared to conventional instrumentation.
... As the neck-shaft angle increases, the polyethylene cup is positioned in a more horizontal orientation, which results in mechanical abutment of the cup along the inferior scapular neck. To address the concern of scapular notching and increasing impingement-free motion, several authors have proposed decreasing the neck-shaft angle to a more vertical or anatomic inclination (i.e., 145°or 135°), which also effectively lateralizes the humerus [54,55]. Using a three-dimensional computer model of RTSA, Ladermann et al. [56] compared the traditional inlay Grammont humeral stem with a short, curved onlay stem with varying humeral neck-shaft angles (155°, 145°, and 135°) and noted a dramatic improvement in adduction, extension, and external rotation with more varus neck-shaft angles (i.e., 145°and 135°) [56]. ...
Purpose of review:
Our understanding of the reverse total shoulder arthroplasty (RTSA) has grown exponentially since Grammont first introduced his design in 1985. There are a multitude of implant-related variables to consider when performing RTSA. The purpose of this article is to provide a review of these design considerations.
Recent findings:
Current literature demonstrates that the traditional Grammont prosthesis has over 90% survivorship at 10 years. Despite these promising results, there have been concerns raised over the significant rate of scapular notching observed. As a result, the traditional RTSA design has been modified to minimize this complication and maximize impingement-free motion. Modern RTSA designs with a cementless, curved, short-stemmed eccentric onlay humeral component combined with a large, lateralized glenosphere placed in 10° of inferior tilt with > 3.5 mm of inferior overhang have been found to provide excellent results. However, all implant design features must be considered on a case-by-case basis to optimize outcome for each patient. Humeral and glenoid implant design variables have evolved as the biomechanics of RTSA have been further elucidated. Consideration of these variables allows the surgeon to maximize joint efficiency, improve impingement-free range of motion, decrease the risk of scapular notching, preserve bone stock, and minimize the risk of instability.
... Retrospectively, more scholars advocate the treatment of tumors around the shoulder girdle with artificial prosthesis replacement. 18,19 While most of these prostheses do not match the patient's anatomy and may affect shoulder function, the advent of 3D printing, which allows for customization, may help solve this dilemma. Beltram et al. 20 presented a customized scapula prosthesis replacement after tumor resection with an MSTS score of 87%. ...
Chondrosarcoma is characterized by the presence of histologically aggressive behavior, and commonly involves the scapula. Currently, limb salvage surgery is the recommended surgical treatment. Owing to the irregularity of the tumor, the suitability of an implant after tumor resection is a challenge for surgeons. Three-dimensional (3D) printing technology has the potential to make personalized limb salvage surgery a reality. We report the case of a 53-year-old man who was diagnosed with chondrosarcoma of the scapula. Considering the low-grade malignancy and lack of invasion of the glenoid, we agreed upon segmental scapula replacement as the treatment protocol. Nevertheless, reconstruction of the irregular bony defect remaining after tumor resection can be complicated. Therefore, a personalized prosthesis and navigation template corresponding to tumor was designed with 3D printing technique, and tumor resection, prosthesis implantation, and rotator cuff reconstruction were completed. The affected shoulder achieved satisfactory function during a 32-month follow-up with no tumor recurrence. 3D printing technique can help implement the individualized design of the implant and accurate reconstruction after tumor resection, simplify complicated operations, improve operational efficiency, and allow early functional recovery.
... The time necessary for production was not reported consistently, and available production times ranged from 2 to 5 weeks at minimum. 16,40 Surgeons may not be willing to wait over a month for device production, which could potentially influence case timing or overall volume or could limit the applicability of PSI to certain elective cases. 17 For surgeons to properly evaluate the practicality and investment value of PSI technology, objective and readily available information on associated costs and time of production is critical. ...
Background:
There has been significant recent emphasis on the use of patient-specific instrumentation (PSI) in shoulder arthroplasty. However, clinical data are lacking to support the increased time and expense associated with PSI. Our purposes were to determine whether PSI significantly improves implantation accuracy during total shoulder arthroplasty (TSA) and to analyze available techniques and correlation with clinical outcomes. We hypothesized that PSI may improve glenoid component position radiographically but without correlation with clinical outcomes.
Methods:
The MEDLINE, Scopus, Embase, and Cochrane Library databases were queried. Included articles reported use of any preoperative or intraoperative PSI techniques, models, or guides to assist with TSA prosthesis implantation. The primary outcomes were mean deviation from the preoperative plan in version (in degrees), inclination (in degrees), and entry-point offset on the glenoid (in millimeters).
Results:
Among the included articles, 518 TSA procedures (352 anatomic and 166 reverse) were performed. The mean postoperative errors in both version and inclination angles were 5° or less in 20 articles (90.9%) using PSI. Meta-analysis revealed no statistically significant differences in version error (P > .999, I2 = 64.6%), inclination error (P = .702, I2 = 82.2%), or positional offset (P = .777, I2 = 85.7%) between PSI and standard instrumentation. No data regarding patient-reported outcome measures, range of motion, strength, or glenoid component loosening and longevity were reported.
Conclusions:
Meta-analysis revealed no significant differences in accuracy between PSI and standard instrumentation. Although PSI may possess the potential to improve TSA techniques, further investigations regarding long-term clinical outcomes, impact on operating room time, and cost-effectiveness are warranted before PSI can be routinely recommended over conventional instrumentation.
... 2,[20][21][22][23] Improvements in surgical techniques and implant design have led to better postoperative outcomes. 21,[24][25][26][27] However, there is a high variability of postoperative shoulder RoM reported in the literature, 28,29 which suggests the influence of other unidentified factors. To the authors' knowledge, no published studies have investigated how different configurations of lateralization and NSA affect shoulder RoM in different scapular morphologies. ...
Objectives
To date, no study has considered the impact of acromial morphology on shoulder range of movement (ROM). The purpose of our study was to evaluate the effects of lateralization of the centre of rotation (COR) and neck-shaft angle (NSA) on shoulder ROM after reverse shoulder arthroplasty (RSA) in patients with different scapular morphologies.
Methods
3D computer models were constructed from CT scans of 12 patients with a critical shoulder angle (CSA) of 25°, 30°, 35°, and 40°. For each model, shoulder ROM was evaluated at a NSA of 135° and 145°, and lateralization of 0 mm, 5 mm, and 10 mm for seven standardized movements: glenohumeral abduction, adduction, forward flexion, extension, internal rotation with the arm at 90° of abduction, as well as external rotation with the arm at 10° and 90° of abduction.
Results
CSA did not seem to influence ROM in any of the models, but greater lateralization achieved greater ROM for all movements in all configurations. Internal and external rotation at 90° of abduction were impossible in most configurations, except in models with a CSA of 25°.
Conclusion
Postoperative ROM following RSA depends on multiple patient and surgical factors. This study, based on computer simulation, suggests that CSA has no influence on ROM after RSA, while lateralization increases ROM in all configurations. Furthermore, increasing subacromial space is important to grant sufficient rotation at 90° of abduction. In summary, increased lateralization of the COR and increased subacromial space improve ROM in all CSA configurations. Cite this article: A. Lädermann, E. Tay, P. Collin, S. Piotton, C-H Chiu, A. Michelet, C. Charbonnier. Effect of critical shoulder angle, glenoid lateralization, and humeral inclination on range of movement in reverse shoulder arthroplasty. Bone Joint Res 2019;8:378–386. DOI: 10.1302/2046-3758.88.BJR-2018-0293.R1.
... The additional expenses involved with outsourcing may be a considerable barrier for many, and production delays of up to 6 weeks per device may deter surgeons from investing substantial resources in such PSI systems. 32 For PSI technology to realistically be considered for widespread use in TSA, it needs to consistently outperform the current surgical standard of care while allowing for efficient and economical modes of production. ...
... 2,9,22e24,27e29,32,34 Although it is impossible to represent the entire spectrum of TSA patients with this sample, the addition of a standard instrumentation control adds further validity that was absent in several previous investigations. 2,13,23,27,32,34 In general, evidence regarding the clinical impact of PSI systems in TSA is lacking. Currently, there are no available data demonstrating significant improvements in patient-reported outcomes or implant longevity after using PSI technology in TSA. ...
Background:
Patient-specific instrumentation (PSI) systems for total shoulder arthroplasty (TSA) can improve glenoid component placement, but may involve considerable expense and production delays. The purpose of this study was to evaluate a novel technique for in-house production of 3-dimensionally printed, patient-specific glenoid guides. We hypothesized that our PSI guide would improve the accuracy of glenoid guide pin placement compared with a standard TSA guide.
Methods:
We randomized 20 cadaveric shoulders to receive pin placement via the PSI guide (n = 10, study group) or standard TSA guide (n = 10, control group). PSI guides were designed to fit each glenoid based on 3-dimensional scapular models constructed from computed tomography scans. A presurgical plan was created for the guide pin trajectory in neutral version and inclination based on individual scapular anatomy. After pin placement, 3-dimensional models from repeated computed tomography scans were superimposed to calculate deviation from the presurgical plan for each specimen.
Results:
Inclination deviation was significantly lower in the PSI group than in the standard guide group (1.5° ± 1.6° vs. 6.4° ± 5.0°, P = .009). The glenoid entry site exhibited significantly less deviation in the PSI group (0.8 ± 0.6 mm vs. 2.1 ± 1.2 mm, P = .008). The average production cost and time for the PSI guides were $29.95 and 4 hours 40 minutes per guide, respectively.
Conclusions:
The PSI guide significantly improved the accuracy of glenoid pin placement compared with the standard TSA guide. Our PSI guides can be produced in-house, inexpensively, and with substantially reduced time compared with commercially available guides.
... Several digitized planning tools have been developed to determine the ideal implant position according to glenoid deformity and Friedman axis [17,18]. Planning also serves to determine the glenoid reconstruction required in severe deformity, with use of grafts, augmented implants or excentric reaming [19][20][21]. Jacquot et al. [22] demonstrated that the surgeon is able to achieve positioning very close to that established on 3D planning. In the particular cases of extensive glenoid or humeral bone defect, revision surgery or tumor resection, CT is essential for determining the dimensions of patient-specific implants [23,24]. ...
... Some of the most frequent complications are the reduction of the Range Of Motion (ROM) and the scapular notching [9], i.e. the erosion of scapula due to its repeated impingement with the humeral prosthetic component. Some authors [10][11][12] report that the incidence of this complication varies between 44% and 96% of all the implants and usually appears between the sixth and the fourteenth month after surgery. ...
Purpose:
Shoulder instability and reduced range of motion are two common complications of a total reverse shoulder arthroplasty. In this work, a new approach is proposed to estimate how the glenoid component positioning can influence the stability and the range of motion of a reverse shoulder prosthesis.
Materials and methods:
A standard reverse shoulder prosthesis has been analysed. To perform virtual simulation of the shoulder-prosthesis assembly, all the components of the prosthesis have been acquired via a 3D laser scanner and the solid models of the shoulder bones have been reconstructed through CT images. Loads on the shoulder joint have been estimated using anatomical models database. A new virtual/numerical procedure has been implemented using a 3D parametric modelling software to find the optimal position of the glenosphere.
Results:
Several analyses have been performed using different configurations obtained by changing the glenoid component tilt and the lateral position of the glenosphere, modified through the insertion of a cylindrical spacer. For the analysed case study, it was found that the interposition of a spacer (between the baseplate and the glenoid) and 15° inferior tilt of the glenosphere allow improving the range of motion and the stability of the shoulder.
Conclusions:
Some common complications of the reverse shoulder arthroplasty could be effectively reduced by a suitable positioning of the prosthesis components. In this work, using a new method based on virtual simulations, the influence of the glenosphere positioning has been investigated. An optimal configuration for the analysed case study has been found. The proposed approach could be used to find, with no in vivo experiments, the optimal position of a reverse shoulder prosthesis depending on the different dimensions and shape of the bones of each patient.
... Baseplate design parameters, in addition to intraoperative positioning, influence biomechanics that are Baseplates are currently either circular or oval with diameters ranging from 25 to 34 millimeters [27]. Baseplates can have flat or curved-backs with or without inferior extensions serving as protective surfaces to limit notching [28]. In an in-vitro study, involving cyclic loading of the prothesis and measuring the post loading baseplate displacement the oval baseplates have demonstrated superior fixation over circular plates while no difference was observed between flat and curved-back designs [29]. ...
Introduction: Historically, patients with rotator cuff arthropathy had limited reconstructive options. The early generations of reverse total shoulder arthroplasty (rTSA) designs had increased failure rates due to loosening of glenoid baseplates secondary to excessive torques. In 1985, Paul Grammont introduced a prosthetic design changing the center of rotation that addressed this major complication. The Grammont principles remain the foundation of modern reverse total shoulder prostheses, although the original design has undergone several adaptations. We reviewed here the various aspects of prosthetic designs including baseplates, glenospheres, humeral components, and polyethylene bearing interfaces.
Areas covered: We discuss the evolution, biomechanics, prosthetic options, and future direction for rTSA. A literature search using the PubMed database including review articles, biomechanical studies, and clinical trials pertaining to rTSA prothesis and outcomes.
Expert commentary: Despite an expansion in the understanding of the biomechanics of the rotator cuff deficient shoulder and its effect on the reverse total shoulder prostheses, Grammont principles remain the foundation of contemporary rTSA designs. Further clinical studies are needed to assess how modern prosthetic modifications effect clinical and radiographic outcomes. Additionally, implants are being used in younger individuals with expanded indications, therefore, close clinical monitoring is needed to better evaluate their prosthetic longevity.
... This system was characterized by three main features: spherical inferior overhang to avoid scapular notching, fixation peg of various sizes to preserve the glenoid bone stock, and adjustable length to reinforce the fixation if needed ( Fig. 1.17). After more improvements, the Duocentric ® Expert reversed prosthesis became available in 2007 [75]. ...
Reverse shoulder arthroplasty replaces the normal glenoid socket with a “glenosphere” fixed to the scapular neck and articulated with a polyethylene socket of the humeral component.
