Clinical and radiographic outcomes with a posteriorly augmented glenoid for Walch B glenoids in anatomic total shoulder arthroplasty

Minimum 10-year follow-up of anatomic total shoulder arthroplasty and ream-and-run arthroplasty for primary glenohumeral osteoarthritis

BACKGROUND

Reports on long term outcomes and failures of shoulder arthroplasty are uncommon. The purpose of this study is to present minimum 10-year outcomes in consecutive patients undergoing ream-and-run and anatomic total shoulder arthroplasty (TSA) for primary glenohumeral arthritis.

METHODS

This study analyzed consecutive patients who had undergone a ream-and-run or TSA with minimum 10-year follow-up. Pain scores and Simple Shoulder Test (SST) values were obtained preoperatively and at a minimum of 10 years postoperatively via e-mail or mail-in response. Percentage of maximum possible improvement (%MPI) was also calculated.

RESULTS

Of 127 eligible patients, 63 (50%) responded to a 10-year survey. This included 34 patients undergoing ream-and-run arthroplasty and 29 patients undergoing TSA. The ream-and-run patients were significantly younger than the TSA patients (60 ± 7 vs. 68 ± 8, P < .001), predominantly male (97% vs. 41%, P < .001), and had a lower American Society of Anesthesiologists classification (P = .018). In the ream-and-run group, the mean pain score improved from a preoperative value of 6.5 ± 1.9 to 0.9 ± 1.3 (P < .001), and the mean SST score improved from 5.4 ± 2.4 to 10.3 ± 2.1 at 10-year follow-up (P < .001). Twenty-eight (82%) achieved an SST improvement above the minimally clinically important difference (MCID) of 2.6. Four patients (12%) underwent single-stage exchange to another hemiarthroplasty, whereas 1 (3%) required manipulation under anesthesia. In the TSA group, the pain score improved from a preoperative value of 6.6 ± 2.2 to 1.2 ± 2.3 (P < .001), and the SST score improved from 3.8 ± 2.6 to 8.9 ± 2.6 at 10-year follow-up (P < .001). Of the 29 patients who underwent a TSA, 27 (93%) achieved an SST improvement above the MCID of 1.6. No patient in the TSA group required reoperation.

CONCLUSION

Although the characteristics of the patients differ between the 2 groups, excellent functional results can be obtained with the ream-and-run arthroplasty and TSA for glenohumeral osteoarthritis.

Clinical outcome of wedged glenoid reconstruction in anatomic total shoulder arthroplasty for osteoarthritic retroverted glenoid: a minimum 2-year follow-up

Background

Glenoid retroversion and humeral head subluxation is a progressive disorder due to abnormal force coupling and increased contact force. In situ placement of anatomic total shoulder arthroplasty (TSA) components in this scenario results in edge loading, progressive subluxation, and early failure. Wedged glenoid components have been demonstrated to improve glenohumeral alignment, but have not been correlated with mid-term clinical outcomes.

Methods

Patients undergoing TSA using a wedged all-polyethylene glenoid component for retroverted glenoid deformity were identified from a prospectively maintained database. Preoperative planning computed tomography was routinely performed and compared to postoperative correction on radiographic evaluation. Evidence of loosening was correlated to prospectively collect clinical outcome using patient-reported outcome measures. A matched group of neutrally aligned glenohumeral joints undergoing anatomic TSA was used to compare improvement in clinical outcomes.

Results

Over a 5-year period, 17 patients with mean age 60 (range 43-81, standard deviation 10.5) were identified with a mean preoperative neoglenoid retroversion of 16.7° (standard deviation 4.5). At a mean follow-up of 43.8 months (range 27-60), no revision surgeries were undertaken. Improvement in the Oxford Shoulder Score was 18 points (P < .0001). The mean improvement was compared to a matched control group demonstrating a comparable magnitude of improvement of 20.4 points.

Conclusion

Wedged polyethylene components for Walch B2-type glenoids in TSA yield acceptable correction of the joint line, excellent clinical outcomes, and survivorship is maintained in the short term. The clinical and radiological outcome demonstrated similar improvement to that seen in A type deformities.

Prognostic value of the Walch classification for patients before and after shoulder arthroplasty performed for osteoarthritis with an intact rotator cuff

BACKGROUND

The Walch classification is commonly used by surgeons when determining the treatment of osteoarthritis (OA). However, its utility in prognosticating patient clinical state before and after TSA remains unproven. We assessed the prognostic value of the modified Walch glenoid classification on preoperative clinical state and postoperative clinical and radiographic outcomes in total shoulder arthroplasty (TSA).

METHODS

A prospectively collected, multicenter database for a single-platform TSA system was queried for patients with rotator cuff-intact OA and minimum 2 year follow-up after anatomic (aTSA) and reverse TSA (rTSA). Differences in patient-reported outcome scores (Simple Shoulder Test, American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form, Shoulder Pain and Disability Index, visual analog scale for pain, Shoulder Function score), combined patient-reported and clinical-input scores (Constant, University of California-Los Angeles shoulder score, Shoulder Arthroplasty Smart Score), active range of motion values (forward elevation [FE], abduction, external rotation [ER], internal rotation [IR], and radiographic outcomes (humeral and glenoid radiolucency line rates, scapula notching rate) were stratified and compared by glenoid deformity type per the Walch classification for aTSA and rTSA cohorts. Comparisons were performed to assess the ability of the Walch classification to predict the preoperative, postoperative, and improved state after TSA.

RESULTS

1008 TSAs were analyzed including 576 aTSA and 432 rTSA. Comparison of outcomes between Walch glenoid types resulted in 15 pairwise comparisons of 12 clinical outcome metrics, yielding 180 total Walch glenoid pairwise comparisons for each clinical state (preoperative, postoperative, improvement). Of the 180 possible pairwise Walch glenoid type and metric comparisons studied for aTSA and rTSA cohorts, <6% and <2% significantly differed in aTSA and rTSA cohorts, respectively. Significant differences based on Walch type were seen after adjustment for multiple pairwise comparisons in the aTSA cohort for FE and ER preoperatively, the Constant score postoperatively, and for abduction, FE, ER, Constant score, and SAS score for pre- to postoperative improvement. In the rTSA cohort, significant differences were only seen in abduction and Constant score both postoperatively and for pre- to postoperative improvement. There were no statistically significant differences in humeral lucency rate, glenoid lucency rate (aTSA), scapular notching rate (rTSA), complication rates, or revision rates between Walch glenoid types after TSA.

CONCLUSION

Although useful for describing degenerative changes to the glenohumeral joint, we demonstrate a weak association between preoperative glenoid morphology according to the Walch classification and clinical state when evaluating patients undergoing TSA for rotator cuff-intact OA. Alternative glenoid classification systems or predictive models should be considered to provide more precise prognoses for patients undergoing TSA for rotator cuff-intact OA.

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.

Accuracy and Reliability of Computerized Surgical Planning Software in Anatomic Total Shoulder Arthroplasty

PURPOSE

The primary purpose of this study was to assess the concordance between preoperatively determined implant parameters using CT-based planning software and surgically implanted prostheses. Secondarily, we sought to evaluate the agreement between preoperative plans performed by surgeons at different levels of training.

METHODS

Patients with primary glenohumeral osteoarthritis who underwent anatomic total shoulder arthroplasty (aTSA) and had a preoperative CT scan according to Blueprint (Stryker, Mahwah, NJ) protocol to be used for preoperative planning were included. A cohort of short-stemmed (SS) and stemless cases performed between October 2017 and December 2018 was randomly selected from an institutional database for the study. Planning was performed separately by four observers at different levels of orthopedic training at a minimum of six months following the actual surgery. Concordance between the surgical decisions during planning and the actually utilized implants was calculated. Additionally, inter-rater agreement was analyzed using the intra-class correlation coefficient (ICC). Implant parameters assessed were glenoid size, backside radius of curvature, and the need for posterior augment, in addition to humeral stem/nucleus size, head size, head height, and head eccentricity.

RESULTS

Twenty-one patients were included (10 stemmed and 11 stemless) with a cohort comprising 12 (57%) females with a median age of 62 years (IQR 59.5,67). There was a total of 544 decision possibilities based on the above parameters. The total number of decisions that matched surgical data was 333 (61.2%). Prediction of glenoid component augmentation need and size was the variable that matched most with surgical data (83.3%), whereas nucleus/stem size was the worst (42.9%). Interobserver agreement was excellent in one variable, good in three variables, moderate in one, and poor in two. The best interobserver agreement was with regard to head height.

CONCLUSION

Preoperative planning using CT-based software may be more accurate for the glenoid component when compared to humeral-sided parameters. Specifically, planning may be most helpful in determining the need and the size of glenoid component augmentation. Utilizing computerized software demonstrates high reliability, even among surgeons early in their orthopedic training.

Anatomic shoulder arthroplasty with high side reaming versus reverse shoulder arthroplasty for eccentric glenoid wear patterns with an intact rotator cuff: comparing early versus midterm outcomes with minimum 7 years of follow-up

BACKGROUND

Eccentric glenoid bone loss patterns (B- and C-type glenoid) pose a difficult challenge when performing shoulder arthroplasty. Anatomic total shoulder arthroplasty with preferential high-side reaming (ATSA + HSR) has been an accepted method to treat this problem. Reverse shoulder arthroplasty (RSA) has become an alternative method to manage these cases with eccentric glenoid wear. The purpose of this study was to compare the early 2-year outcomes with the midterm outcomes for patients who underwent ATSA + HSR vs. RSA for eccentric glenoid wear patterns with an intact rotator cuff.

MATERIALS AND METHODS

From 2008 to 2014 there were 242 shoulder arthroplasties performed in the setting of eccentric glenoid wear patterns. Of that initial cohort 101 ATSA + HSR and 93 RSA had both 2-year and final follow-up with a minimum of 7 years from surgery. American Shoulder and Elbow Surgeons (ASES) scores, Simple Shoulder Test (SST), range of motion, patient satisfaction, and radiographs were evaluated for each cohort and contrasted at the 2-year follow-up point and last follow-up time point.

RESULTS

The average follow-up in the ATSA + HSR cohort was 8.3 years compared with 7.8 years in the RSA cohort. At the 2-year follow-up point, the ATSA + HSR group had better average ASES scores (85 vs. 80 [P < .001]), SST scores (10 vs. 9.6 [P < .001]), forward elevation (162° vs. 151° [P < .001]), external rotation (47° vs. 42° [P < .001]), and internal rotation (IR) (80% full IR vs. 55% full IR [P < .001]). At the 2-year follow-up, 95% of the ATSA + HSR cohort were satisfied compared with 93% in the RSA cohort. At the final follow-up, the RSA group had better average ASES scores (80 vs. 77 [P < .001]) and SST scores (9.4 vs. 8 [P < .001]) and a similar forward elevation (152° vs. 149° [P = .025]). The ATSA + HSR had better external rotation (45° vs. 41° [P < .001]) and IR (74% full IR vs. 54% full IR [P = .005]). Patient satisfaction at the final follow-up had decreased to 82% in the ATSA + HSR group, compared with 95% satisfied in the RSA group. Of the initial ATSA + HSR cohort, 8% of patients had undergone revision compared with 2% in the RSA cohort.

CONCLUSION

ATSA with HSR had better outcome scores and range of motion with a similar patient satisfaction rating to RSA at the 2-year point. Over time, the ATSA + HSR results deteriorated, and at the final midterm follow-up, the RSA group had more durable results with better outcome scores, a higher patient satisfaction rating, and a lower revision rate.

Midterm results of pyrocarbon interposition shoulder arthroplasty: good outcomes after posttraumatic osteonecrosis without malunion of the tuberosities

Background

In vitro data demonstrate the potential benefits of the pyrocarbon as a bearing material against cartilage or bone. And pyrocarbon-free interposition arthroplasty has been used with positive outcomes for over 10 years for hand and wrist joint replacements. This study reports the midterm results of a Pyrocarbon Interposition Shoulder Arthroplasty (PISA) in primary and secondary glenohumeral osteoarthritis and in avascular osteonecrosis.

Methods

This prospective noncontrolled, multicenter study included 67 consecutive patients who underwent PISA in France and Sweden.

Results

A cohort of 48 patients, aged 50 ± 12 years, was available for clinical assessment at a mean follow-up of 67.6 ± 9.3 months. A favorable change was reported with a mean absolute Constant score improvement of 32 ± 20 points. The highest Constant score improvement was observed in patients with avascular osteonecrosis (42 ± 18 points; P ≤ .0001). Between the earliest and the latest follow-up, radiographic analyses revealed only 2 major glenoid erosions and 4 tuberosity thinnings and thus that 86.4% of 44 shoulders remained stable with no or minor radiologic evolutions. The survival rate was 84 % at 65 months of follow-up considering all causes of revision.

Conclusion

The radiographic findings seem to confirm the interest of pyrocarbon in preserving bony surfaces. But the risk of tuberosity thinning suggests considering the use of PISA with caution in most degenerative glenohumeral joint pathologies, although the midterm outcomes highlight PISA as a suitable solution for patients presenting with posttraumatic osteonecrosis without malunion of the tuberosities and with an intact rotator cuff.

Characteristics of anatomic and reverse total shoulder arthroplasty patients who achieve ceiling scores with 3 common patient-reported outcome measures

BACKGROUND

Legacy shoulder outcome scores have postoperative ceiling scores effects when quantifying clinical outcomes for anatomic (aTSA) and reverse (rTSA) total shoulder arthroplasty patients. This study uses data from an international database of a single shoulder prosthesis using data from 30 different clinical sites to quantify and compare the percentage of aTSA and rTSA patients achieving postoperative ceiling scores with multiple outcome measures and defines the patient demographics, comorbidities, implant, and operative parameters associated with ceiling scores for each outcome measure.

METHODS

Clinical outcomes for 1817 aTSA and 2635 rTSA patients between 2007 and 2019 were quantified with the American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES), Simple Shoulder Test (SST), the University of California, Los Angeles (UCLA), Constant, and Shoulder Arthroplasty Smart (SAS) scores. The number of aTSA and rTSA patients with ceiling scores were calculated and sorted into those that achieved ceiling scores with the SST, ASES, and UCLA measures and compared to patients without ceiling scores. A univariate and multivariate analysis then identified the patient demographics, comorbidities, and implant and operative parameters associated with ceiling scores for each outcome measure.

RESULTS

aTSA patients achieved ceiling scores at a significantly greater rate than rTSA patients for all outcome measures, except SAS. The SST score was the most susceptible to ceiling scores (aTSA = 43.4%, rTSA = 34.1%, P < .0001), followed by the ASES (aTSA = 23.7%, rTSA = 13.3%, P < .0001) and UCLA (aTSA = 22.2%, rTSA = 10.6%, P < .0001) scores. Ceiling scores were least likely with the Constant (aTSA = 0.4%, rTSA = 0%, P = .0060) and SAS (aTSA = 0.1%, rTSA = 0%, P = .0750) scores. Male patients had a significantly higher ceiling score rate than female patients using the SST and ASES scores, and no differences in ceiling score rates were observed with the UCLA, Constant, or SAS scores. Finally, we identified numerous patient demographic, comorbidity, implant, and operative parameters associated with SST, ASES, and UCLA ceiling scores for aTSA and rTSA patients.

DISCUSSION

Postoperative ceiling scores occur at a high rate for aTSA and rTSA patients with the SST, ASES, and UCLA scores. Those most susceptible to ceiling scores are aTSA patients treated with cage glenoids, aTSA patients of lower body mass index, rTSA patients of male gender, rTSA patients with osteoarthritis diagnosis, and rTSA patients with subscapularis repair. Clinical researchers should consider using alternative scores, such as the SAS score, to ensure a more normalized distribution of data and more accurately quantify aTSA and rTSA outcomes.

The addition of preoperative three-dimensional analysis alters implant choice in shoulder arthroplasty

BACKGROUND

The primary objective of the present study was to investigate how preoperative imaging modalities including 3D computed tomography (CT) scans with preoperative planning software affect implant choice for shoulder arthroplasty.

METHODS

X-ray, uncorrected 2D CT scans, and 3D CT scans from 21 patients undergoing primary arthroplasty were reviewed by five shoulder surgeons. Each surgeon measured glenoid version, inclination and humeral head subluxation, and then selected an anatomic or reverse shoulder arthroplasty implant based only on these imaging parameters. Each surgeon virtually positioned the implant. Agreement between surgeons and changes in plan for individual surgeons between imaging modalities were assessed.

RESULTS

Average measurements of native version, inclination, and subluxation were similar across all imaging modalities with very good interobserver reliability. Overall, there was a high rate of variability in choice of implant depending on imaging modality. Agreement on implant selection between surgeons improved from 68.6% using x-ray to 80.0% with 3D CT. Introducing age added significant variability, reducing agreement on implant choice to 61.0% with 3D CT.

CONCLUSIONS

The use of preoperative 3D planning changes implant choice in nearly one-third of cases compared to plain radiographs and improves surgeon agreement on implant choice compared to x-ray and 2D CT.Level of evidence: III.

Early clinical and radiographic outcomes of anatomic total shoulder arthroplasty with a biconvex posterior augmented glenoid for patients with posterior glenoid erosion: minimum 2-year follow-up

BACKGROUND

Glenoid bone loss in anatomic total shoulder arthroplasty (aTSA) remains a controversial and challenging clinical problem. Previous studies have shown high rates of glenoid loosening for aTSA in shoulders with retroversion, posterior bone loss, and posterior humeral head subluxation. This study is the first to present minimum 2-year follow-up data of an all-polyethylene, biconvex augmented anatomic glenoid component for correction of glenoid retroversion and posterior humeral head subluxation.

METHODS

This study is a multicenter, retrospective review of prospectively collected data on consecutive patients from 7 global clinical sites. All patients underwent aTSA using the biconvex posterior augmented glenoid (PAG). Inclusion criteria were preoperative computed tomographic (CT) scan, minimum 2 years since surgery, preoperative and minimum 2-year postoperative range of motion examination, and patient-reported outcome measures (PROMs). Glenoid classification, glenoid retroversion, and posterior humeral head subluxation were measured from preoperative CT and radiography and postoperative radiography. Statistical comparisons between pre- and postoperative values were performed with a paired t test.

RESULTS

Eighty-six of 110 consecutive patients during the study period (78% follow-up) met the inclusion criteria and were included in our analysis. Mean follow-up was 35 ± 10 months, with a mean age of 68 ± 8 years (range 48-85). Range of motion statistically improved in all planes from pre- to postoperation. Mean visual analog scale score improved from 5.2 preoperation to 0.7 postoperation, Single Assessment Numeric Evaluation score from 43.2 to 89.5, Constant score from 41.8 to 76.9, and American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form score from 49.8 to 86.7 (all P < .0001). Mean glenoid retroversion improved from 19.3° to 7.4° (P < .0001). Posterior subluxation improved from 69.1% to 53.5% and posterior decentering improved from 5.8% to -3.0% (P < .0001). There was 1 patient with both a prosthetic joint infection and radiographic glenoid loosening that required revision. Seventy-nine of 86 patients had a Lazarus score of 0 (no radiolucency seen about peg or keel) at final follow-up.

CONCLUSIONS

This study shows that at minimum 2-year follow-up, a posterior-augmented all-polyethylene glenoid can correct glenoid retroversion and posterior humeral head subluxation. Clinically, there was significant improvement in both range of motion and PROMs.

Substantial Inconsistency and Variability Exists Among Minimum Clinically Important Differences for Shoulder Arthroplasty Outcomes: A Systematic Review

BACKGROUND

As the value of patient-reported outcomes becomes increasingly recognized, minimum clinically important difference (MCID) thresholds have seen greater use in shoulder arthroplasty. However, MCIDs are unique to certain populations, and variation in the modes of calculation in this field may be of concern. With the growing utilization of MCIDs within the field and value-based care models, a detailed appraisal of the appropriateness of MCID use in the literature is necessary and has not been systematically reviewed.

QUESTIONS/PURPOSES

We performed a systematic review of MCID quantification in existing studies on shoulder arthroplasty to answer the following questions: (1) What is the range of values reported for the MCID in commonly used shoulder arthroplasty patient-reported outcome measures (PROMs)? (2) What percentage of studies use previously existing MCIDs versus calculating a new MCID? (3) What techniques for calculating the MCID were used in studies where a new MCID was calculated?

METHODS

The Embase, PubMed, and Ovid/MEDLINE databases were queried from December 2008 through December 2020 for total shoulder arthroplasty and reverse total shoulder arthroplasty articles reporting an MCID value for various PROMs. Two reviewers (DAK, MAM) independently screened articles for eligibility, specifically identifying articles that reported MCID values for PROMs after shoulder arthroplasty, and extracted data for analysis. Each study was classified into two categories: those referencing a previously defined MCID and those using a newly calculated MCID. Methods for determining the MCID for each study and the variability of reported MCIDs for each PROM were recorded. The number of patients, age, gender, BMI, length of follow-up, surgical indications, and surgical type were extracted for each article. Forty-three articles (16,408 patients) with a mean (range) follow-up of 20 months (0.75 to 68) met the inclusion criteria. The median (range) BMI of patients was 29.3 kg/m2 (28.0 to 32.2 kg/m2), and the median (range) age was 68 years (53 to 84). There were 17 unique PROMs with MCID values. Of the 112 MCIDs reported, the most common PROMs with MCIDs were the American Shoulder and Elbow Surgeons (ASES) (23% [26 of 112]), the Simple Shoulder Test (SST) (17% [19 of 112]), and the Constant (15% [17 of 112]).

RESULTS

The ranges of MCID values for each PROM varied widely (ASES: 6.3 to 29.5; SST: 1.4 to 4.0; Constant: -0.3 to 12.8). Fifty-six percent (24 of 43) of studies used previously established MCIDs, with 46% (11 of 24) citing one study. Forty-four percent (19 of 43) of studies established new MCIDs, and the most common technique was anchor-based (37% [7 of 19]), followed by distribution (21% [4 of 19]).

CONCLUSION

There is substantial inconsistency and variability in the quantification and reporting of MCID values in shoulder arthroplasty studies. Many shoulder arthroplasty studies apply previously published MCID values with variable ranges of follow-up rather than calculating population-specific thresholds. The use of previously calculated MCIDs may be acceptable in specific situations; however, investigators should select an anchor-based MCID calculated from a patient population as similar as possible to their own. This practice is preferable to the use of distribution-approach MCID methods. Alternatively, authors may consider using substantial clinical benefit or patient-acceptable symptom state to assess outcomes after shoulder arthroplasty.

CLINICAL RELEVANCE

Although MCIDs may provide a useful effect-size based alternative to the traditional p value, care must be taken to use an MCID that is appropriate for the particular patient population being studied.

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

BACKGROUND

The objective was to evaluate the short-term clinical and radiological outcomes following augmented anatomic total shoulder arthroplasty in patients with posterior glenoid deficiency.

METHODS

An electronic search of EMBASE, MEDLINE, and PubMed identified studies reporting clinical and radiographic outcomes following augmented anatomic total shoulder arthroplasty among patients with posterior glenoid deficiency.

RESULTS

Nine studies including 312 shoulders underwent anatomic total shoulder arthroplasty using an augmented glenoid implant between 2015 and 2020. A statistically significant improvement in range of motion (ROM), visual analog scale (VAS), American Shoulder & Elbow Surgeons (ASES), Constant, University of California - Los Angeles and Simple Shoulder Test (SST) scores was demonstrated at mean follow-up of 37.1 months. Glenoid retroversion improved from 21.8° to 9.5°. At final follow-up, radiolucency was reported in 35.1% of shoulders. The 16° full-wedge augment led to higher and more severe radiographic lucency, while high peg perforation rates (44%) were observed among 5-mm augment stepped implants. The overall rate of complication was 2.6%. Rate of revision surgery was 1.9%.

CONCLUSIONS

Overall, early- to mid-term outcomes following augmented anatomic total shoulder arthroplasty for posterior glenoid deficiency demonstrate good to excellent overall clinical results. More radiographic and clinical failures were reported in larger full wedge (16°) augments and stepped augments (5 mm). Prospective studies examining mid- and long-term outcomes will help further elucidate safety and efficacy of these relatively new implants.

The Evolution of Reverse Total Shoulder Arthroplasty-From the First Steps to Novel Implant Designs and Surgical Techniques

PURPOSE OF REVIEW

The purpose of this review is to summarize recent literature regarding the latest design modifications and biomechanical evolutions of reverse total shoulder arthroplasty and their impact on postoperative outcomes.

RECENT FINDINGS

Over the past decade, worldwide implantation rates of reverse total shoulder arthroplasty have drastically increased for various shoulder pathologies. While Paul Grammont's design principles first published in 1985 for reverse total shoulder arthroplasty remained unchanged, several adjustments were made to address postoperative clinical and biomechanical challenges such as implant glenoid loosening, scapular notching, or limited range of motion in order to maximize functional outcomes and increase the longevity of reverse total shoulder arthroplasty. However, the adequate and stable fixation of prosthetic components can be challenging, especially in massive osteoarthritis with concomitant bone loss. To overcome such issues, surgical navigation and patient-specific instruments may be a viable tool to improve accurate prosthetic component positioning. Nevertheless, larger clinical series on the accuracy and possible complications of this novel technique are still missing.

Variability and reliability of 2-dimensional vs. 3-dimensional glenoid version measurements with 3-dimensional preoperative planning software

BACKGROUND

Preoperative planning for total shoulder arthroplasty (TSA) may change according to the measured degree of glenoid version. Both 2-dimensional (2D) and 3-dimensional (3D) computed tomographic (CT) scans are used to measure glenoid version, with no consensus on which method is more accurate. However, it is generally accepted that 3D measurements are more reliable, yet most 3D reconstruction software currently in clinical use have never been directly compared to 2D. The purpose of this study is to directly compare 2D and 3D glenoid version measurements and determine the differences between the two.

METHODS

CT scans were performed preoperatively on 315 shoulders undergoing either anatomic or reverse TSA. 2D measurements of glenoid version were obtained manually using the Friedman method, whereas 3D measurements were obtained using the Equinoxe Planning Application (Exactech Inc.) 3D-reconstruction software. Negative version values indicate retroversion, whereas positive values indicate anteversion. Two observers collected the 2D measurements 2 separate times, and intra- and interobserver measurements were calculated. Groups were compared for variability using intraclass correlation coefficients (ICCs), and for differences in sample means using Student t tests. Additionally, samples were stratified by version value in order to better understand the potential sources of error between measurement techniques.

RESULTS

For the 2D measurements, intraobserver variability indicated excellent reproducibility for both observer 1 (ICC = 0.928, 95% confidence interval [CI] 0.911-0.942) and observer 2 (ICC = 0.964, 95% CI 0.955-0.971). Interobserver variability measurements also indicated excellent reproducibility (ICC = 0.915, 95% CI 0.778-0.956). The overall 2D version measurement average (-4.9° ± 10.3°) was significantly less retroverted than the 3D measurement average (-8.4° ± 9.1°) (P < .001), with 3D measurements yielding a more retroverted value 73% of the time. When stratified on the basis of version value with outliers excluded, there was no significant difference in the distribution of high-error samples within the data.

DISCUSSION

There was excellent reproducibility between the 2 observers in terms of both intra- and interobserver variability. The 3D measurement techniques were significantly more likely to return a more retroverted measurement, and high-error samples were evenly distributed throughout the data, indicating that there were no discernable trends in the degree of error observed. Shoulder surgeons should be aware that different glenoid version measurement strategies can yield different version measurements, as these can affect preoperative planning and surgeon decision making.

Anatomic vs. reverse shoulder arthroplasty for the treatment of Walch B2 glenoid morphology: a systematic review and meta-analysis

Background

Walch B2 glenoid morphology with glenohumeral osteoarthritis is a difficult degenerative pattern to manage for shoulder surgeons. Anatomic total shoulder arthroplasty (TSA) in combination with eccentric reaming or bone grafting are the traditional methods of treatment. Newer approaches such as TSA with posteriorly augmented glenoid components and reverse shoulder arthroplasty (RSA) may offer better stability for the posteriorly subluxated biconcave B2 wear pattern. The aim of this systematic review is to compare mid-term surgical and functional outcomes of Walch B2 glenoids without significant rotator cuff pathology treated with TSA and RSA.

Methods

The review was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines by searching the MEDLINE (PubMed) and Embase (Elsevier) databases. Inclusion criteria were clinical studies that evaluated the outcomes and complications of TSA or RSA in the setting of B2 glenoid morphology without significant rotator cuff pathology. Data relevant to TSA and RSA surgical outcomes were extracted and compiled, and outcomes were compared. A meta-analysis of proportions of complication and revision rates among TSA and RSA groups was performed.

Results

Overall, 16 articles were included with 414 TSAs and 78 RSAs. The average follow-up duration was 54.1 ± 14.8 months for patients undergoing TSA and 44.8 ± 10.1 months for patients undergoing RSA. The TSA group was further subdivided based on the use of eccentric reaming (135 TSAs), an augmented glenoid component (84 TSAs), or bone grafting (11 TSAs) or was unspecified (184 TSAs). Overall, patients undergoing TSA and RSA demonstrated mean improvements of 50.1 ± 8.5° and 64.7 ± 5.2° in active flexion, 58.5 ± 10.3° and 68.9 ± not reported° in active abduction, and 31.3 ± 5.7° and 29.0 ± 10.2° in active external rotation, respectively. In regard to functional outcome scores, patients undergoing TSA and RSA showed mean Constant score improvements of 38.8 ± 5.3 and 46.6 ± 3.1 points and American Shoulder and Elbow Surgeons score improvements of 48.2 ± 1.0 and 49.2 ± 25.3 points, respectively. Results of the meta-analysis with mid-term follow-up data demonstrated pooled complication rates of 9% (95% confidence interval [CI], 1%-22%) for TSA and 6% (95% CI, 0%-28%) for RSA and pooled revision rates of 2% (95% CI, 0%-8%) for TSA and 1% (95% CI, 0%-15%) for RSA.

Conclusion

In the setting of Walch B2 glenoid morphology, TSA with eccentric reaming or an augmented component yields comparable outcomes to RSA. Based on the patient's age, activity level, and expectations, both TSA and RSA can be considered a reasonable option to treat Walch B2 glenoid morphology.

Subluxation in the Arthritic Shoulder

»

The term "subluxation" means partial separation of the joint surfaces. In the arthritic shoulder, "arthritic glenohumeral subluxation" refers to displacement of the humeral head on the surface of the glenoid.

»

The degree of arthritic glenohumeral subluxation can be measured using radiography with standardized axillary views or computed tomography (CT).

»

Shoulders with a type-B1 or B2 glenoid may show more posterior subluxation on an axillary radiograph that is made with the arm in an elevated position than on a CT scan that is made with the arm at the side.

»

The degree of arthritic glenohumeral subluxation is not closely related to glenoid retroversion.

»

The position of the humeral head with respect to the plane of the scapula is related to glenoid retroversion and is not a measure of glenohumeral subluxation.

»

Studies measuring glenohumeral subluxation before and after arthroplasty should clarify its importance to the clinical outcomes of shoulder reconstruction.

Complications After Anatomic Shoulder Arthroplasty: Revisiting Leading Causes of Failure

For practicing shoulder arthroplasty surgeons, it is advisable to consider a breadth of data sources concerning complications and outcomes. Although published series from high-volume centers are the primary source of data, these results may not be generalizable to a wide range of practice settings. National or health system-specific registry and medical device databases are useful adjuncts to assess the changing complication profile of shoulder arthroplasty, as well as to understand the complications specific to certain implants or implant types. To reduce the risk of postoperative complications, surgeons must have a clear understanding of the most common modes of failure.

Assessing the Value to the Patient of New Technologies in Anatomic Total Shoulder Arthroplasty

BACKGROUND

Publications regarding anatomic total shoulder arthroplasty (TSA) have consistently reported that they provide significant improvement for patients with glenohumeral arthritis. New TSA technologies that have been introduced with the goal of further improving these outcomes include preoperative computed tomography (CT) scans, 3-dimensional preoperative planning, patient-specific instrumentation, stemless and short-stemmed humeral components, as well as metal-backed, hybrid, and augmented glenoid components. The benefit of these new technologies in terms of patient-reported outcomes is unknown.

METHODS

We reviewed 114 articles presenting preoperative and postoperative values for commonly used patient-reported metrics. The results were analyzed to determine whether patient outcomes have improved over the 20 years during which new technologies became available.

RESULTS

The analysis did not identify evidence that the results of TSA were statistically or clinically improved over the 2 decades of study or that any of the individual technologies were associated with significant improvement in patient outcomes.

CONCLUSIONS

Additional research is required to document the clinical value of these new technologies to patients with glenohumeral arthritis.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Short-stem uncemented anatomical shoulder replacement for osteoarthritis in patients older than 70 years: is it appropriate?

Background

Despite a new trend to systematically use reverse shoulder arthroplasty (RSA) in elderly population regardless of the indication, total anatomical shoulder arthroplasty can get good functional results in this population. The purpose of this study was to evaluate clinical and radiological outcomes of uncemented short-stem anatomic total shoulder arthroplasty (TSA) for primary glenohumeral osteoarthritis in patients older than 70 years and to compare these results to a matched population with an uncemented short-stem RSA.

Methods

In this retrospective monocentric study, clinical outcomes were based on constant score (Cst), subjective shoulder value (SSV) score, and range of motion. The aim of radiographic analysis was to identify glenoid component loosening and humeral bone remodeling around the uncemented short stem.

Results

At an average follow-up of 44 ± 12.5 months, 32 uncemented short-stem TSA in 31 patients with a minimum of 2 years of follow-up were included and were compared to 32 uncemented RSA. Fifty three percent of the patients had “a forgotten prosthesis”. ROM was significantly improved in all cases. Cst reached 73 ± 9 pts and SSV 90 ± 10.8% (P < .001). In 8 patients with repairable supraspinatus tendon tears, clinical outcomes were not statistically different from patients with an intact rotator cuff: Cst (77 ± 6.2 points vs 72 ± 9.6 points, P = .3) and SSV (88 ± 11.5% vs. 91 ± 10.5%; P = .59). The type of glenoid wear (A vs B) did not influence the constant score: 73 ± 9 points versus 74 ± 11 points respectively; P = .81. Despite a complication rate of 6% (n = 2), no prosthesis revision was performed. At last follow-up, range of motion was better in the TSA group compared to the RSA group for internal (7.8 ± 1.3 vs 6.25 ± 2; P = .001) and external (47 ± 14 vs 24 ± 21; P < .001) rotations. The postoperative SSV score was also better in the TSA group (91.3 ± 10% vs 82.2 ± 13%; P = .002).

Conclusions

At medium-term, uncemented short-stem anatomic TSA in patients older than 70 years provided satisfactory clinical results. Patients have forgotten their prosthesis in over 50% of cases. This prosthetic design is still indicated in this patient population in case of primary osteoarthritis with a functional rotator cuff with an almost normal rotator cuff muscle trophicity.

Intersurgeon and intrasurgeon variability in preoperative planning of anatomic total shoulder arthroplasty: a quantitative comparison of 49 cases planned by 9 surgeons

BACKGROUND

Preoperative planning software is widely available for most anatomic total shoulder arthroplasty (ATSA) systems. It can be most useful in determining implant selection and placement with advanced glenoid wear. The purpose of this study was to quantify inter- and intrasurgeon variability in preoperative planning of a series of ATSA cases.

METHODS

Forty-nine computed tomography scans were planned for ATSA by 9 fellowship-trained shoulder surgeons using the ExactechGPS platform (Exactech Inc., Gainesville, FL, USA). Each case was planned a second time between 4 and 12 weeks later. Variability within and between surgeons was measured for implant type, size, version and inclination correction, and implant face position. Interclass correlation coefficients, Pearson, and Light's kappa coefficients were used for statistical analysis.

RESULTS

There was considerable variation in the frequency of augment use between surgeons and between rounds for the same surgeon. Thresholds for augment use also varied between surgeons. Interclass correlation coefficients for intersurgeon variability were 0.37 for version, 0.80 for inclination, 0.36 for implant type, and 0.36 for implant size. Pearson coefficients for intrasurgeon variability were 0.17 for version and 0.53 for inclination. Light's kappa coefficient for implant type was 0.64.

CONCLUSIONS

This study demonstrates substantial inter- and intrasurgeon variability in preoperative planning of ATSA. Although the magnitude of differences in correction was small, surgeons differed significantly in the use of augments to achieve the resultant plan. Surgeons differed from each other on thresholds for augment use and maximum allowable residual retroversion. This suggests that there may a range of acceptable corrections for each shoulder rather than a single optimal plan.

The glenoid and humeral head in shoulder osteoarthritis: A comprehensive review

The key management of glenohumeral osteoarthritis is shoulder arthroplasty which aims to reduce pain and restore full shoulder function: it has increased in recent years. A detailed understanding of the anatomy of the glenoid and humeral head, as well as morphological changes of the glenoid in osteoarthritis, are important factors to consider when deciding on replacement components. This review begins with a brief introduction of the glenohumeral joint itself, and then considers the detailed anatomy of the glenoid fossa and humeral head, both of which are reported to have variable morphology. Several studies have been undertaken to assess various parameters, especially of the glenoid fossa including its shape, height, width, and articular surface area, version and inclination, in an attempt to define a standard classification that can be applied to surgical intervention. Nevertheless, no definitive consensus concerning the classification of these morphologies has been forthcoming, hence the need for this review. Following a consideration of these morphologies, the current state of knowledge regarding glenoid deformity in osteoarthritis, as well as its surgical management, is considered.