Early outcomes of augmented glenoid components in anatomic total shoulder arthroplasty: a systematic review

Does glenoid version and its correction affect outcomes in anatomic shoulder arthroplasty? A systematic review

BACKGROUND

Correction of glenoid retroversion is commonly performed in anatomic total shoulder arthroplasty (TSA) to increase component contact area and decrease eccentric loading of the glenoid component. Despite demonstrated biomechanical advantages, limited information exists on the clinical benefit of correcting glenoid retroversion. The purpose of this systematic review is to critically evaluate the existing literature on the effect of preoperative and postoperative glenoid retroversion on clinical functional and radiologic outcomes in patients who underwent anatomic TSA.

METHODS

A systematic literature review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses using PubMed, Embase, and Cochrane Library evaluating the impact of glenoid retroversion on clinical and radiologic outcomes of TSA. English-language studies of level I through IV evidence were included. Blinded reviewers conducted multiple screens and methodological quality was appraised using the Modified Coleman Methodology Score.

RESULTS

Sixteen studies, including 3 level III and 13 level IV studies (1211 shoulders), satisfied all inclusion criteria. To address glenoid retroversion, 9 studies used corrective reaming techniques, and 4 studies used posteriorly augmented glenoids. Two studies used noncorrective reaming techniques. Mean preoperative retroversion ranged from 12.7° to 24° across studies. Eleven studies analyzed the effect of glenoid retroversion on clinical outcomes, including patient-reported outcome scores (PROs), range of motion (ROM), or clinical failure or revision rates. Most studies (8 of 11) did not report any significant association of pre- or postoperative glenoid retroversion on any clinical outcome. Of the 3 studies that reported significant effects, 1 study reported a negative association between preoperative glenoid retroversion and PROs, 1 study reported inferior postoperative abduction in patients with postoperative glenoid retroversion greater than 15°, and 1 study found an increased clinical failure rate in patients with higher postoperative retroversion. Ten studies reported radiographic results (medial calcar resorption, Central Peg Lucency [CPL] grade, Lazarus lucency grade) at follow-up. Only 1 study reported a significant effect of pre- and postoperative retroversion greater than 15° on CPL grade.

CONCLUSION

There is currently insufficient evidence that pre- or postoperative glenoid version influences postoperative outcomes independent of other morphologic factors such as joint line medialization. Given that noncorrective reaming demonstrated favorable postoperative outcomes, and postoperative glenoid version was not significantly and consistently found to impact outcomes, there is inconclusive evidence that correcting glenoid retroversion is routinely required.

Revision rate in metal compared to ceramic humeral head total shoulder arthroplasty and hemiarthroplasty

Aims

Metal and ceramic humeral head bearing surfaces are available choices in anatomical shoulder arthroplasties. Wear studies have shown superior performance of ceramic heads, however comparison of clinical outcomes according to bearing surface in total shoulder arthroplasty (TSA) and hemiarthroplasty (HA) is limited. This study aimed to compare the rates of revision and reoperation following metal and ceramic humeral head TSA and HA using data from the National Joint Registry (NJR), which collects data from England, Wales, Northern Ireland, Isle of Man and the States of Guernsey.

Methods

NJR shoulder arthroplasty records were linked to Hospital Episode Statistics and the National Mortality Register. TSA and HA performed for osteoarthritis (OA) in patients with an intact rotator cuff were included. Metal and ceramic humeral head prostheses were matched within separate TSA and HA groups using propensity scores based on 12 and 11 characteristics, respectively. The primary outcome was time to first revision and the secondary outcome was non-revision reoperation.

Results

A total of 4,799 TSAs (3,578 metal, 1,221 ceramic) and 1,363 HAs (1,020 metal, 343 ceramic) were included. The rate of revision was higher for metal compared with ceramic TSA, hazard ratio (HR) 3.31 (95% confidence interval (CI) 1.67 to 6.58). At eight years, prosthesis survival for ceramic TSA was 98.7% (95% CI 97.3 to 99.4) compared with 96.4% (95% CI 95.2 to 97.3) for metal TSA. The majority of revision TSAs were for cuff insufficiency or instability/dislocation. There was no significant difference in the revision rate for ceramic compared with metal head HA (HR 1.33 (95% CI 0.76 to 2.34)). For ceramic HA, eight-year prosthetic survival was 92.8% (95% CI 86.9 to 96.1), compared with 91.6% (95% CI 89.3 to 93.5) for metal HA. The majority of revision HAs were for cuff failure.

Conclusion

The rate of all-cause revision was higher following metal compared with ceramic humeral head TSA in patients with OA and an intact rotator cuff. There was no difference in the revision rate for HA according to bearing surface.

Patient-reported outcomes following total shoulder arthroplasty and hemiarthroplasty: an analysis of data from the National Joint Registry

BACKGROUND

Total shoulder arthroplasty (TSA) and hemiarthroplasty (HA) are used in the management of end-stage glenohumeral arthritis. Improvement in shoulder function and resolution of symptoms are high priorities for patients. The aim of this study was to compare patient-reported outcome measures (PROMs) following TSA and HA.

METHODS

Records from the National Joint Registry of England, Wales, Northern Ireland, and the Isle of Man were linked to the PROMs data set. The study included anatomic shoulder arthroplasties performed for osteoarthritis in patients with an intact rotator cuff. Patients with preoperative and postoperative Oxford Shoulder Scores (OSSs) were included. The improvement in OSS at 6 months and 5 years and the trend in scores over time were analyzed for each prosthesis. A cohort of 2002 patients were matched on 10 variables using propensity scores. OSSs at 6 months following TSA vs. HA were compared in the matched sample.

RESULTS

There was a significant improvement in the OSS in both groups (P < .001). At 6 months, the OSSs were superior following TSA compared with HA (median 42 vs. 36, P < .001). The median score at 5 years was 44 following TSA and 35 following HA. Score distributions were skewed toward the maximum score. The highest possible score (48) was achieved in 28% (134 of 478) of TSAs and 9% (20 of 235) of HAs at 5 years. The improvement in the preoperative to 6-month OSS reached the minimal clinically important difference of 5.5 in 92% (1653 of 1792) of TSAs and in 80% (416 of 523) of HAs. At 5 years, this improvement was maintained in 91% (339 of 374) of TSAs and 78% (136 of 174) of HAs.

CONCLUSION

TSA resulted in superior OSSs at 6 months in patients with osteoarthritis. The median OSS improved from 6 months to 5 years following TSA; however, there was a small decline in scores following HA. A ceiling effect was shown in the OSS following TSA at 5 years.

The risk of revision is higher following shoulder hemiarthroplasty compared with total shoulder arthroplasty for osteoarthritis: a matched cohort study of 11,556 patients from the National Joint Registry, UK

BACKGROUND AND PURPOSE

Total shoulder arthroplasty (TSA) and hemiarthroplasty (HA) are used in the management of osteoarthritis of the glenohumeral joint. We aimed to determine whether TSA or HA resulted in a lower risk of adverse outcomes in patients of all ages with osteoarthritis and an intact rotator cuff and in a subgroup of patients aged 60 years or younger.

PATIENTS AND METHODS

Shoulder arthroplasties recorded in the National Joint Registry, UK, between April 1, 2012 and June 30, 2021, were linked to Hospital Episode Statistics in England. Elective TSAs and HAs were matched on propensity scores based on 11 variables. The primary outcome was all-cause revision. Secondary outcomes were combined revision/non-revision reoperations, 30-day inpatient complications, 1-year mortality, and length of stay. 95% confidence intervals (CI) were reported.

RESULTS

11,556 shoulder arthroplasties were included: 7,641 TSAs, 3,915 HAs. At 8 years 95% (CI 94-96) of TSAs and 91% (CI 90-92) of HAs remained unrevised. The hazard ratio (HR) varied across follow-up: 4-year HR 2.7 (CI 1.9-3.5), 8-year HR 2.0 (CI 0.5-3.5). Rotator cuff insufficiency was the most common revision indication. In patients aged 60 years or younger prosthesis survival at 8 years was 92% (CI 89-94) following TSA and 84% (CI 80-87) following HA.

CONCLUSION

The risk of revision was higher following HA in patients with osteoarthritis and an intact rotator cuff. Patients aged 60 years and younger had a higher risk of revision following HA.

Anatomic glenohumeral arthroplasty: State of the art

Anatomical total shoulder arthroplasty in its modern form where it reproduces the normal shoulder has been utilized clinically for more than half a century. As the technology and the designs have changed to recreate the humeral and glenoid sides of the joint, the sophistication of design has resulted in the growing number of cases annually worldwide. This increase is due in part to the increasing number of indications that the prosthesis can treat with successful results. On the humeral side, there have been design changes to better reflect the proximal humeral anatomy, and humeral stems are increasingly placed safely without cement. Platform systems which allow conversion of a failed arthroplasty to a reverse configuration without stem extraction is another design change. Similarly, there has been increasing utilization of short stem and stemless humeral components. Extensive experience with shorter stem and stemless devices, however, has yet to demonstrate the purported advantages of these devices, as recent studies have demonstrated equivalent blood loss, fracture rates, operative times, and outcome scores. Easier revision with these shorter stems remains to be definitively established, with only one study comparing the ease of revision between stem types. On the glenoid side, hybrid cementless glenoids, inlay glenoids, cementless all-polyethylene glenoids, and augmented glenoids have all been investigated; however, the indications for these devices remain unclear. Lastly, innovative surgical approaches to implanting shoulder arthroplasty and the use of patient specific guides and computerized planning, while interesting concepts, still await validation before they are utilized on a widespread basis. While reverse shoulder arthroplasty has been increasingly used to reconstruct the arthritic shoulder, anatomic glenohumeral replacement maintains a significant role in the armamentarium of the shoulder surgeon.

Treatment of Glenoid Wear with the Use of Augmented Glenoid Components in Total Shoulder Arthroplasty: A Scoping Review

» Treatment of glenoid bone loss continues to be a challenge in total shoulder arthroplasty (TSA). Although correcting glenoid wear to patient's native anatomy is desirable in TSA, there is lack of consensus regarding how much glenoid wear correction is acceptable and necessary in both anatomic and reverse TSA.» Use of augmented glenoid components is a relatively new treatment strategy for addressing moderate-to-severe glenoid wear in TSA. Augmented glenoid components allow for predictable and easy correction of glenoid wear in the coronal and/or axial planes while at the same time maximizing implant seating, improving rotator cuff biomechanics, and preserving glenoid bone stock because of off-axis glenoid reaming.» Augmented glenoid components have distinct advantages over glenoid bone grafting. Glenoid bone grafting is technically demanding, adds to the surgical time, and carries a risk of nonunion and graft resorption with subsequent failure of the glenoid component.» The use of augmented glenoid components in TSA is steadily increasing with easy availability of computed tomography-based preoperative planning software and guidance technology (patient-specific instrumentation and computer navigation).» Although different augment designs (full wedge, half wedge, and step cut) are available and a particular design may provide advantages in specific glenoid wear patterns to minimize bone removal (i.e. a half wedge in B2 glenoids), there is no evidence to demonstrate the superiority of 1 design over others.

Shoulder arthroplasty in patients with glenohumeral osteoarthritis, glenoid bone loss and an intact rotator cuff: an algorithmic approach and review of the literature

In patients with severe glenohumeral osteoarthritis (OA) and preserved rotator cuff function who have failed nonoperative treatment, anatomic total shoulder arthroplasty (TSA) has historically been the preferred surgical treatment. Shoulder arthroplasty in the setting of glenoid bone loss setting is technically demanding. Many techniques have been described to deal with glenoid bone loss including eccentric reaming, bone grafting, augmented glenoid baseplates, and patient-specific implants. Still, the decision to perform anatomic TSA or reverse total shoulder arthroplasty (RTSA) is often unclear, especially as the use of RTSA increases and evolves, making historical studies less useful when considering modern implant designs. RTSA has been advocated as a solution for patients with severe glenoid bone loss with intact rotator cuff function. Moreover, in appropriately selected patients, good outcomes can be achieved without the use of bone grafting or augmented baseplates. In cases of severe glenoid bone loss, RTSA can be performed with reaming the glenoid flat such that the baseplate rests on native glenoid bone. We have previously reported excellent prosthetic survival with this technique at 5-year follow-up. The purpose of this article is to highlight our suggested treatment algorithm for glenohumeral OA with glenoid bone loss and intact rotator cuff. Specifically, we focus on situations where RTSA may be preferred as opposed to anatomic TSA, and our suggested approach to managing bone loss intraoperatively in this complex patient population.

Temporary Protective Shoulder Implants for Revision Surgery with Bone Glenoid Grafting

This article describes the development of a temporary protective glenoid prosthesis placed between the augmentation and humeral head prosthesis during the healing phase of shoulder prosthesis revision with necessary reconstruction of the bony structure of the glenoid. The glenoid protection prosthesis ensures the fixation of the augmentation material and protects the screws from contact with the metallic humeral head prosthesis. Another approach of the development is a reduction of the resorption of the augmentation by targeted mechanical stimulation of the tissue. The aim should be to achieve significantly improved conditions for the implantation of a new glenoid component at the end of the healing phase of the augmentation material in comparison to the current standard method. The development of the protective prosthesis was carried out according to specific needs and includes the collection of requirements and boundary conditions, the design and technical detailing of the implant, the verification of the development results as well as the validation of the design. For the verification, FEM simulations (Finite Element Analysis) were performed to estimate the mechanical stability in advance. Mechanical tests to confirm the stability and abrasion behavior have been carried out and confirm the suitability of the protective implant. The result of the present work is the detailed technical design of two variants of a glenoid protective prosthesis "GlenoProtect" for use in revision procedures on shoulder joints-with large-volume defects on the glenoid-treated by arthroplasty and the necessity of augmenting the glenoid, including a description of the surgical procedure for implantation.