Glenoid Wear Research Articles

Hemiarthroplasty in young patients.

The survival of humeral hemiarthroplasties in patients with relatively intact glenoid cartilage could theoretically be extended by minimizing the associated postoperative glenoid erosion. Ceramic has gained attention as an alternative to metal as a material for hemiarthroplasties because of its superior tribological properties. The aim of this study was to assess the in vitro wear performance of ceramic and metal humeral hemiarthroplasties on natural glenoids. Intact right cadaveric shoulders from donors aged between 50 and 65 years were assigned to a ceramic group (n = 8, four male cadavers) and a metal group (n = 9, four male cadavers). A dedicated shoulder wear simulator was used to simulate daily activity by replicating the relevant joint motion and loading profiles. During testing, the joint was kept lubricated with diluted calf serum at room temperature. Each test of wear was performed for 500,000 cycles at 1.2 Hz. At intervals of 125,000 cycles, micro-CT scans of each glenoid were taken to characterize and quantify glenoid wear by calculating the change in the thickness of its articular cartilage. At the completion of the wear test, the total thickness of the cartilage had significantly decreased in both the ceramic and metal groups, by 27% (p = 0.019) and 29% (p = 0.008), respectively. However, the differences between the two were not significant (p = 0.606) and the patterns of wear in the specimens were unpredictable. No significant correlation was found between cartilage wear and various factors, including age, sex, the size of the humeral head, joint mismatch, the thickness of the native cartilage, and the surface roughness (all p > 0.05). Although ceramic has better tribological properties than metal, we did not find evidence that its use in hemiarthroplasty of the shoulder in patients with healthy cartilage is a better alternative than conventional metal humeral heads.

Can Subscapularis Deficiency Explain Glenoid Wear (Thus Possibly Glenohumeral Pain)

Can Subscapularis Deficiency Explain Glenoid Wear (Thus Possibly Glenohumeral Pain)

Glenoid wear and migration pattern of a humeral head resurfacing implant: a prospective study using radio stereometric analysis

Background and purposeThe humeral head resurfacing arthroplasty (HHR) is normally used as a hemi shoulder arthroplasty and has been in use for the treatment of Gleno-Humeral osteoarthritis of the shoulder (OA) for more than 30 years. Some studies, however, shows that anatomical total shoulder arthroplasty provides better improvement in function than a HHR for patients with OA. Reasons for this may be a progressive glenoid wear (GW) or loosening of the HHR. We therefore wanted to investigate the migration pattern (MP) of the HHR and also GW by using Radio Stereometric Analysis (RSA). Patients and methods21 patients (21 shoulders) with OA and a mean age of 64 years were enrolled in the study. They all received the Copeland humeral resurfacing head and were followed for 2 years with RSA. We evaluated the clinical outcome at 2 years with Western Ontario Osteoarthritis of the Shoulder (WOOS), EuroQol 5 dimension 3L (EQ-5D) and Constant Shoulder Score (CSS). In addition, we assessed data on WOOS and revisions until 5 years follow-up by using the local clinic data within the Swedish Shoulder Arthroplasty Register. ResultsAfter an initial migration at two months the implants were stable in relation to the humerus with no statistically significant difference between the 2 months and the 2 years value (p=0.23). The GW continued to increase during the study period with an initial migration of mean 2.3 mm and at 2 years 3.5 mm with a statistically difference between the 6 months and 2 years value (p=0.046). The WOOS, EQ-5D and CSS were all improved at 2 years compared to the preoperative values. We found a weak correlation between GW at 2 years and the WOOS score at 2 and 5 years, but these did not reach statistical significance. There were 4 revisions within 5 years after the primary operation, all due to pain. ConclusionThe marker-free RSA can be used in clinical studies for assessing migration in HHR implants and was also for the first time used to measure GW. The Copeland HHR seems to obtain a secure fixation in the humerus but shows continuous GW up to two years.

Modular baseplate augmentation: a simple and effective method for addressing eccentric glenoid wear

BackgroundAugmented baseplates can be effective at addressing eccentric glenoid wear in reverse total shoulder arthroplasty (rTSA). However, these implants often come in a limited number of predetermined shapes that require additional reaming to ensure adequate glenoid seating. This typically involves complex instrumentation and can have a negative impact on implant stability. Modular baseplate augmentation based on intra-operative measurements may allow for more precise defect filling while preserving glenoid bone. The purpose of this investigation was to assess the stability of a novel ringed baseplate with modular augmentation in comparison to non-augmented standard and ringed baseplate designs. MethodsIn this biomechanical study, baseplate micromotion was tested for three constructs according to American Society for Testing and Materials (ASTM) guidelines. The constructs included a non-augmented curved baseplate, a non-augmented ringed baseplate and ringed baseplate with an 8 mm locking modular augmentation peg. The non-augmented constructs were mounted flush onto polyurethane (PU) foam blocks, while the augmented baseplate was mounted on a PU block with a simulated defect. Baseplate displacement was measured prior to and after 100,000 cycles of cyclic loading. ResultsPrior to cyclic loading, the non-augmented and augmented ringed baseplates both demonstrated significantly less micromotion than the non-augmented curved baseplate design (81.1 μm vs 97.2 μm vs 152.7 μm; p=0.009). After cyclic loading, both ringed constructs continued to have significantly less micromotion compared to the curved design (105.5 μm vs 103.2 μm vs 136.6 μm; p<0.001). The micromotion for both ringed constructs remained below the minimum threshold required for bony ingrowth (150 μm) at all time points. ConclusionIn the setting of a simulated glenoid defect, locked modular augmentation of a ringed baseplate does not result in increased baseplate micromotion when compared to full contact, non-augmented baseplates. This design offers a simple method for tailored baseplate augmentation that can match specific variations in glenoid anatomy, limiting the need for excessive reaming and ultimately optimizing the environment for long term implant stability. Level of EvidenceBasic Science Study; Biomechanics

Comparison of short- and midterm outcomes in patients following ream-and-run and anatomic total shoulder arthroplasties

Anatomic total shoulder arthroplasty (aTSA) may not be an ideal treatment option for young and active patients because of potential activity restriction and concerns about glenoid loosening. The ream-and-run procedure (RnR) allows for the continuance of high-level activity without concerns of a glenoid component failure. Initial RnR publications are promising, although more outcomes studies are needed. Therefore, our primary purpose was to compare outcomes at multiple time points between matched aTSA and RnR cohorts. Second, we sought to examine relationships between patient-reported outcomes and preoperative glenoid pathoanatomy in our RnR cohort Last, we examined postoperative radiographs to determine if the RnR successfully corrected glenoid pathoanatomy and humeral head decentering. We performed a retrospective matched-cohort study comparing patients who underwent an RnR vs. patients who underwent the aTSA procedure between 2017 and 2019. All patients had primary diagnoses of shoulder osteoarthritis and a minimum of 2-year follow-up. Simple Shoulder Test, American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES), and daily and worst pain outcomes were compared between groups at 3 and 6 months, and 1 and 2 years postarthroplasty. Pre- and postoperative glenoid anatomy and humeral decentering were measured radiographically, and correlation analyses were conducted to explore relationships between these factors and 2-year pain and function scores. Forty-six shoulders (23 RnR and 23aTSA) belonging to 43 male patients with an average age of 56.2±8.3 years were included. Eighteen matched pairs were available at 3 and 6 months, 21 matched pairs at 1 year, and all 23 matched pairs at the 2-year time point. RnR patients reported significantly higher daily pain ratings (P=.047) and lower ASES scores (P=.031) compared with the aTSA group 3 months after arthroplasty but reported similar outcomes at 6 months and beyond. Preoperative pathoanatomy outcomes were not directly related to final reported pain or function in the RnR group. Additionally, the RnR was able to correct posterior humeral head decentering in our cohort. Young male patients undergoing RnR can likely expect similar short-term results as young male patients who undergo aTSA. Additionally, the RnR outcomes were not affected by preoperative glenoid wear or humeral head decentering. Our findings support the RnR as a viable surgical alternative for young, active patients with shoulder arthritis.

Long-term (minimum 10 years) survival and outcomes of pyrocarbon interposition shoulder arthroplasty

There are some major controversies surrounding the use and longevity of pyrocarbon interposition shoulder arthroplasty (PISA). The objective of this study was to investigate the long-term survival and outcomes (minimum 10-year) following PISA for osteoarthritis (OA) in young and active patients. This was a retrospective review of prospectively collected data of patients who underwent PISA (InSpyre; Tornier-Stryker) for OA between 2009 and 2012. Arthroplasty survival was known for 71 patients followed longitudinally for a minimum of 10 years. The clinical and radiologic outcomes were assessed in 62 patients (62 shoulders) reviewed with radiographs. The mean age at surgery was 60 years (range, 23-72 years), and 31 shoulders (50%) underwent prior surgery before PISA. The diagnosis was primary osteoarthritis (POA=29), post-traumatic osteoarthritis (PTOA=23), and postinstability osterarthritis (PIOA=10). Clinical failure was defined as repeat surgical intervention involving prosthesis revision. Clinical outcomes were assessed with the Constant score (CS) and Subjective Shoulder Value (SSV). The mean duration of follow-up was 11±0.6 years (range, 10-14 years). Overall, the survival rate was 90% (95% confidence interval [CI] 82.8-96.8) at 5 years and 87% (95% CI 79-94.8) at a 10-year follow-up. Survival was 100% in PTOA (type 1 fracture sequelae) and in PIOA as well as 95% in primary OA with type A glenoid. Revision surgery was significantly higher in biconcave (type B2) glenoid (44%) compared with concentric (type A) glenoid (2%), respectively (P=.002). Among the 7 patients who were revised to reverse shoulder arthroplasty, 5 had painful glenoid erosion and 2 had bipolar (glenoid and humeral) erosion with thinning and finally fracture of the greater tuberosity. Two shoulders with glenohumeral erosion were associated with secondary rotator cuff tears (1 supraspinatus and 1 subscapularis tear). The mean time to revision and revision was 4±1.7 years. Glenoid wear was more often superior (81%) than central (19%), P<.001. For those shoulders not revised, the mean CS and SSV significantly increased from 39±14 to 70±14 points and 34%±15% to 75%±17%, respectively (P<.001). PISA is an efficient and durable surgical procedure for the treatment of young and active patients with post-traumatic OA, postinstability OA, and primary OA with concentric (type A) glenoid erosion, but not for those with biconcave (type B2) glenoid. Biconcave (type B2) glenoid and subscapularis tear or insufficiency are risk factors for failure and revision.

Comparison of early and late aseptic baseplate failure in primary reverse shoulder arthroplasty with and without structural glenoid autograft

Early reverse total shoulder arthroplasty (RTSA) designs demonstrated high glenoid baseplate complication and revision rates. While contemporary designs have reduced the incidence of glenoid baseplate failures, there are reports of elevated failure risks in RTSA with glenoid bone grafting within the first 2 years. This study aims to evaluate the incidence and etiology of aseptic glenoid baseplate failure with a contemporary central screw baseplate. The null hypothesis is that majority of the baseplate failure occurs within the first 2 years and use of glenoid bone grafting does not lead to higher risk of baseplate failure. In 2014 - 2019, 753 consecutive patients who underwent primary RSA using the same inlay press-fit humeral stem and monoblock central screw baseplate were retrospectively reviewed. Fracture and septic arthropathy cases were excluded. All patients underwent preoperative radiographic and computed tomography evaluation. If there was significant glenoid erosion (Walch A2, B2, B3, C1, C2, E2, E3, and/or E4 variants), patient-specific structural glenoid bone grafting was performed. All patients underwent standardized radiographic follow-up and failure was strictly defined as any hardware breakage and/or shift in glenoid baseplate position. Failures were defined as "early" if occurring within 2 years and "late" if occurring greater than 2 years after surgery. Comparative analysis was performed to evaluate demographics, glenoid graft use, and graft union rates between the cohorts. There were 23 patients with baseplate failures (23/753, 3.0%) at mean of 23 months. Twenty-two failures (96%) occurred in patients who received structural glenoid bone grafting. Only 1 failure (0.2%) occurred when bone grafting was not indicated (p<0.001). The most common failure pattern was associated with B2 glenoid (16/23, 70%). There were 5 (22%) early failures and 18 (78%) late failures. There were no differences in any patient demographic characteristics between cohorts. All 5 early failures had graft nonunion and 4/5 occurred without trauma. In the 18 late failures , 9/18 (50%) occurred without trauma (p=0.135). Seventeen of these patients had glenoid grafting, of which 9/17 (53%) had graft nonunion. Contemporary RTSA glenoid baseplate designs have an acceptably low incidence of failure. However, the addition of structural bone graft to correct glenoid wear leads to higher aseptic baseplate failure rate. The majority of these patients suffer failure after the 2-year postoperative mark, highlighting the necessity of longer follow-up. Further analysis is necessary to quantify glenoid characteristics (severity of glenoid erosion, critical size of graft) associated with failure.

Functional composite spacer (antibiotic cement around a hemiarthroplasty) for the treatment of shoulder infections: minimum 5-year outcomes

Periprosthetic infections remain a challenging complication after shoulder arthroplasty, and an ideal treatment protocol has yet to be established. Two-stage revision is a common approach. Historically, the first stage entails placement of an all-cement antibiotic spacer. Although prior studies have reported on cement spacers as definitive management, persistent pain and inadequate function often lead many to later request a second-stage procedure. The functional composite spacer consists of a humeral hemiarthroplasty implant with antibiotic cement coated around the stem alone to preserve the metallic humeral head-glenoid articulation. Functional composite spacers have demonstrated improvements in function and motion with high patient satisfaction at 25 months, but longer-term follow-up is needed to better understand the role it may play in the management of shoulder infections. The purpose of this study is to evaluate outcomes at a minimum of 5 years in patients who initially planned to undergo 2-stage revision but elected to retain the functional spacer. A retrospective review of a single institution's shoulder surgery repository from 2007 to 2018 identified 30 patients who underwent placement of a composite spacer. Overall, 5 patients underwent second-stage reimplantation and 12 patients did not have 5-year follow-up (6 lost to follow-up and 6 deceased). A total of 13 patients were included who maintained a functional composite spacer and had minimum 5-year follow-up. Patient-reported outcome measures (American Shoulder and Elbow Surgeons score, Simple Shoulder Test, Single Assessment Numeric Evaluation, visual analog scale function, and visual analog score pain), satisfaction, range of motion, and radiographic estimation of glenoid wear were evaluated. Two of 13 patients (15%) required additional surgery: 1 secondary closure for early superficial wound dehiscence and 1 revision spacer for pain. There were no reinfections. At most recent follow-up, patient satisfaction was high and significant improvements were noted for American Shoulder and Elbow Surgeons score (45.4; P<.001), Simple Shoulder Test (5.3; P=.003), Single Assessment Numeric Evaluation (47.3; P=.002), visual analog scale function (4.9; P=.004), and visual analog score pain (-4.4; P=.007) as well as range of motion including abduction (39.2°; P=.005) and elevation (65.9°; P=.005). There was no significant change in humeral head medialization (P=.11). Patients who do not undergo an early revision and retain a functional composite spacer maintain good function and range of motion with minimal pain at midterm follow-up.

Use of computed tomography for shoulder arthroplasty: A systematic review

IntroductionThe prevalence of total shoulder arthroplasties is on the rise annually. Improvements in implant quality, construct stability, and surgical techniques have notably enhanced post-operative results, prompting an expansion of indications for shoulder arthroplasty. Despite its high success rate, opportunities for enhancement remain, especially in preoperative planning and intraoperative execution. Advanced imaging technologies offer significant potential in optimizing implant placement, thus improving the longevity of the procedure. To our knowledge, a comprehensive review examining the impact of advanced imaging on shoulder arthroplasty has yet to be conducted. This systematic review aims to investigate the benefits of advanced imaging technologies in this context, focusing on their application in preoperative planning, osteoarthritis assessment, intraoperative adjustments, patient-specific instrumentation, and navigational aids. MethodsThis review utilized a comprehensive search of PubMed to identify relevant studies published from 2000 to 2024, focusing on the application of various imaging techniques in shoulder arthroplasty. The search was conducted by two authors and centered on plain radiography, CT scans, and MRI. The selection criteria included availability of full-text articles, English language, direct comparison of imaging techniques, and a focus on patient outcomes, including discussions on broader applications such as intraoperative navigation and patient-specific instrumentation development. ResultsEnhanced imaging techniques, particularly CT scans and MRIs, have been shown to significantly improve outcomes in shoulder arthroplasty. While plain radiographs remain standard, CT scans provide superior bony detail, crucial for evaluating glenoid wear and determining augmentation needs. Preoperative CT imaging has been demonstrated to enhance implant placement accuracy. Moreover, intraoperative technologies based on CT imaging, such as patient-specific instrumentation and navigation systems, contribute to better surgical results. ConclusionThe benefits of CT imaging in shoulder arthroplasty significantly outweigh the associated costs. Current literature strongly supports the adoption of CT imaging in these procedures, particularly when used alongside modern operative technologies.

How anatomic should anatomic total shoulder arthroplasty be? Evaluation of humeral head reconstruction with the best-fit circle

IntroductionHumeral implant designs for anatomic total shoulder arthroplasty (aTSA) focus on anatomic reconstruction of the articular segment. Likewise, the pathoanatomy of advanced glenohumeral osteoarthritis (GHOA) often results in humeral head deformity. We hypothesized the anatomic reconstruction of the humeral head in aTSA risks overstuffing the glenohumeral joint. Methods97 cases (52 females) of primary GHOA in patients treated with aTSA were evaluated. Preoperative computed tomography (CT) scans were used to classify glenoid morphology according to the Walch classification. Coronal plane images in the plane of the humerus were used to determine the anatomic perfect circle as described by Youderian et al. Humeral head thinning was determined as the distance from the center of rotation (COR) of the perfect circle to the nearest point along the humeral articular surface. aTSA was modeled with a predicted anatomic humeral head and a simulated 4 mm polyethylene glenoid component. The change in the position of the native humerus was determined. Wilcoxon Rank Sum tests were used to evaluate differences in humeral head thinning and humeral lateralization between monoconcave and biconcave glenoid morphologies. Spearman’s rank correlation coefficients were used to assess the relationship between humeral head thinning with preoperative active forward elevation and external rotation. ResultsThe mean radius of the perfect circle was 25.0±2.1 mm. There was a mean thinning of 2.4±2.0 mm (Range -1.7–8.3). Mean percent thinning of the humeral head was 9.4%±7.7%. The mean humeral lateralization was 6.4±2.0 mm. Humeral head thinning was not significantly associated with active forward elevation (r=-0.15, p=0.14) or active external rotation (r= -0.12, p=0.25). There were no significant differences in the percentage of humeral head thinning (p=0.324) or humeral lateralization (p=0.350) between concentric and eccentric glenoid wear patterns ConclusionsUtilization of the perfect circle as a guide in aTSA may risk excessive lateralization of the humerus and overstuffing the glenohumeral joint. This may have implications for subscapularis repair and healing, as well as glenoid implant and rotator cuff longevity. These findings call into question whether recreation of normal glenohumeral anatomy in aTSA is appropriate for all patients. Humeral head reconstruction in aTSA should account for glenohumeral joint volume and soft tissue contracture.

Clinical and radiological outcomes with an augmented baseplate for superior glenoid wear in reverse shoulder arthroplasty.

This study aimed to assess the impact of using the metal-augmented glenoid baseplate (AGB) on improving clinical and radiological outcomes, as well as reducing complications, in patients with superior glenoid wear undergoing reverse shoulder arthroplasty (RSA). From January 2016 to June 2021, out of 235 patients who underwent primary RSA, 24 received a superior-AGB after off-axis reaming (Group A). Subsequently, we conducted propensity score matching in a 1:3 ratio, considering sex, age, follow-up duration, and glenoid wear (superior-inclination and retroversion), and selected 72 well-balanced matched patients who received a standard glenoid baseplate (STB) after eccentric reaming (Group B). Superior-inclination, retroversion, and lateral humeral offset (LHO) were measured to assess preoperative glenoid wear and postoperative correction, as well as to identify any complications. Clinical outcomes were measured at each outpatient visit before and after surgery. There were no significant differences in demographic data and preoperative characteristics between the two groups. Both groups showed significant improvements in patient-reported outcome measures (visual analogue scale for pain, visual analogue scale for function, American Shoulder and Elbow Surgeons, Constant, and Simple Shoulder Test scores) from preoperative to final assessment (p < 0.001). However, AGB showed no additional benefit. Notably, within range of motion, Group B showed significant postoperative decrease in both external rotation and internal rotation, unlike Group A (p = 0.028 and 0.003, respectively). Both groups demonstrated a significant correction of superior-inclination after surgery, while patients in Group B exhibited a significant decrease in LHO postoperatively (p = 0.001). Regarding complications, Group A experienced more acromial stress fractures (3 cases; 12.5%), whereas Group B had a higher occurrence of scapular notching (24 cases; 33.3%) (p = 0.008). Both eccentric reaming with STB and off-axis reaming with AGB are effective methods for addressing superior glenoid wear in RSA, leading to improved clinical outcomes. However, it is important to be aware of the potential risks associated with eccentric reaming, which include excessive bone loss leading to reduced rotation and scapular notching.

Patients 75 years or older with primary glenohumeral arthritis and an intact rotator cuff show similar clinical improvement after reverse or anatomic total shoulder arthroplasty

BackgroundThe optimal management of primary glenohumeral arthritis (GHOA) in the elderly is an ongoing topic of debate. The purpose of this study was to compare functional outcomes and complications in patients aged 75 years or older treated with anatomic total shoulder arthroplasty (TSA) or reverse shoulder arthroplasty (RSA) for primary GHOA with an intact rotator cuff. MethodsA retrospective study was performed on a prospectively maintained database which was queried for patients 75 years of age or older who underwent TSA or RSA for primary GHOA with an intact rotator cuff at a single institution between 2012 and 2021 with minimum 2-year follow-up. Patient-reported outcomes (PROs), including Visual Analog Scale for pain (VAS), American Shoulder and Elbow Surgeons (ASES), and Subjective Shoulder Value (SSV), as well as active range of motion including forward flexion (FF), external rotation (ER), internal rotation (IR), were collected pre- and postoperatively. Complications, reoperations, and satisfaction were also recorded. The percentage of patients achieving clinically significant improvement was evaluated with the minimally clinical important difference (MCID), substantial clinical benefit (SCB), and patient acceptable symptomatic state (PASS) for each PRO. ResultsOne-hundred and four patients were available for analysis, including 67 TSA patients and 37 RSAs with a mean follow-up of 39.4 months. Preoperative baseline characteristics, PROs, and ROM were similar between groups. RSA was more commonly performed for eccentric glenoid wear (Walch B2/B3, 62% vs 22%; p < 0.001). While clinical outcomes improved comparably in both groups, the TSA cohort showed significantly greater improvement in ER (36° vs 26°; p=0.013). Both cohorts had low revision (3% for TSA vs 0% for RSA) and complication (7% for TSA vs 5% for RSA; p=0.677) rates. Satisfaction was similar in both groups (93% for TSA vs 92% for RSA; p=0.900). Clinically significant improvement was comparable between groups based on the ASES score (MCID, 93% for TSA vs 100% for RSA; SCB, 82% vs 95%; PASS, 67% vs 78%; p > 0.05). ConclusionIn this retrospective small sample size comparison study, TSA and RSA provide similar short-term clinical outcomes for patients 75 years and older with primary GHOA and an intact rotator cuff. Complication and revision rates are comparably low at short-term follow-up. Our data suggests that advanced age alone should not be used as a decision-making tool for TSA versus RSA in the setting of primary GHOA with an intact rotator cuff.

A narrative review of treatment strategies for major glenoid defects during primary reverse shoulder arthroplasty, with a focus on the use of structural bone graft.

Structural glenoid defects are common during primary reverse shoulder arthroplasty (RSA) and are often associated with poor outcomes. The lack of pre-operative imaging protocols for determining the depth and degree of glenoid wear hinders our ability to accurately plan and correct these defects. Although bone grafting has been reported to be effective in reducing glenoid wear during RSA, there is limited information on when to utilise it and how to prepare the graft. We conducted this review to assess the evidence for the management of glenoid defects, with an emphasis on bone grafts to treat structural glenoid bone loss in primary RSA patients.

3-dimensionally printed patient-specific glenoid drill guides vs. standard nonspecific instrumentation: a randomized controlled trial comparing the accuracy of glenoid component placement in anatomic total shoulder arthroplasty

Traditional, commercially-sourced patient-specific instrumentation (PSI) systems for shoulder arthroplasty improve glenoid component placement but can involve considerable cost and outsourcing delays. The purpose of this randomized controlled trial was to compare the accuracy of glenoid component positioning in anatomic total shoulder arthroplasty (aTSA) using an in-house, point-of-care, 3-dimensionally (3D) printed patient-specific glenoid drill guide versus standard non-specific instrumentation. This single-center randomized controlled trial included 36 adult patients undergoing primary aTSA. Patients were blinded and randomized 1:1 to either the PSI or the standard aTSA guide groups. The primary endpoint was accuracy of glenoid component placement (version and inclination), which was determined using a metal-suppression CT scan taken between 6 weeks to 1 year postoperatively. Deviation from the preoperative 3D templating plan was calculated for each patient. Blinded postoperative CT measurements were performed by a fellowship-trained shoulder surgeon and a musculoskeletal radiologist. Nineteen patients were randomized to the patient-specific glenoid drill guide group, and 17 were allocated to the standard instrumentation control group. There were no significant differences between the two groups for native version (p = 0.527) or inclination (p = 0.415). The version correction was similar between the two groups (p = 0.551), and the PSI group was significantly more accurate when correcting version than the control group (p = 0.042). The PSI group required a significantly greater inclination correction than the control group (p = 0.002); however, the two groups still had similar accuracy when correcting inclination (p = 0.851). For the PSI group, there was no correlation between accuracy of component placement and native version, native inclination, or Walch classification of glenoid wear (p > 0.05). For the control group, accuracy when correcting version was inversely correlated with native version (p = 0.033), but accuracy was not correlated with native inclination or Walch classification of glenoid wear (p > 0.05). The intraclass correlation coefficient (ICC) was 0.703 and 0.848 when measuring version and inclination accuracy respectively. When compared to standard instrumentation, the use of in-house, 3D-printed, patient-specific glenoid drill guides during aTSA led to more accurate glenoid component version correction and similarly accurate inclination correction. Additional research should examine the influence of proper component position and use of patient-specific instrumentation on clinical outcomes.

Midterm outcomes following humeral head replacement with rotator cuff reconstruction for cuff tear arthropathy in patients younger than 65 years of age

BackgroundHumeral head replacement (HHR) using a small-diameter head with rotator cuff reconstruction is a useful therapeutic option for cuff tear arthropathy (CTA) with relatively low complication and revision rates, particularly in younger patients. This study evaluated the medium- to long-term clinical and radiographic outcomes of HHR for CTA in patients under 65 years old who were followed up for at least 5 years. MethodsThis retrospective case series included 16 shoulders of 15 patients under 65 years old who underwent HHR for CTA between 2007 and 2013 (12 shoulders in men, 4 in women). The mean age at surgery was 59.6 (range, 54-64) years. The mean follow-up duration was 8.5 (range, 6.2-11.0) years. No patient needed a revision surgery during the follow-up period. Clinical outcomes were evaluated using the Japanese Orthopedic Association (JOA) score before and 2, 5, and at least 8 years postoperatively. All cases were followed for at least 5 years and 11 were followed for more than 8 years. Glenoid wear (GW), humeral bone resorption, and loosening of the humeral stem were evaluated on radiographs. Final clinical outcomes were evaluated according to GW and bone resorption. ResultsNo serious complications occurred during or after surgery, and the implant survival rate was 100%. Statistically significant improvements in all clinical parameters were found at 2 and 5 years postoperatively. At the final follow-up, there were significant improvements in active flexion (89.7° ± 42.4° vs. 146.8° ± 21.2° P = .01), JOA pain score (5.9 ± 2.0 vs. 22.7 ± 7.5, P = .005), and total JOA score (52.5 ± 9.6 vs. 81.9 ± 9.5, P < .001). GW at the final follow-up was grade 0 in 2 shoulders, grade 1 in 3, grade 2 in 4, and grade 3 in 7 (3A, 1; 3B, 3; and 3C, 3). Grade 4 bone resorption occurred in only 1 case at zone 1. No stem loosening was observed. There was no significant difference in the final clinical outcome according to GW or bone absorption. ConclusionThe results of HHR for CTA were stable and satisfactory with no serious complications or need for revision in patients under 65 years old. Moreover, there was no significant decline in clinical outcomes from the short to long term. Grade 3 GW occurred in 43.8% of cases but without any discernible effect on clinical outcomes.

Anatomic and Reverse Shoulder Arthroplasty for Management of B2 and B3 Glenoids: A Matched Cohort Analysis.

Severe glenohumeral osteoarthritis (GHOA) with posterior glenoid erosion remains challenging to address for shoulder surgeons. While anatomic total shoulder arthroplasty (TSA) has historically been the choice treatment, reverse shoulder arthroplasty (RSA) offers an alternative option. Limited evidence exists directly comparing these two treatments in a similar patient population. The purpose of this study was to compare the clinical outcomes of patients with GHOA and Walch B2 and B3 glenoid morphologies treated with TSA and RSA. A multi-center retrospective cohort study was performed on patients with GHOA treated with primary shoulder arthroplasty and a minimum of 2-year follow-up. Preoperative computed tomography was used to determine B2 and B3 glenoid morphology as described by the modified Walch classification. Three-dimensional perioperative planning software was used to characterize glenoid retroversion and humeral subluxation. Patients were categorized based on TSA or RSA and matched 1:1 by gender, Walch classification, and age. Patient reported outcome measures (PROMs), active range of motion, presence and severity of glenoid loosening, and complications were compared. The percentage of patients that reached previously established clinically significant thresholds for minimal clinically important difference (MCID) and substantial clinical benefit (SCB) for the American Shoulder and Elbow Surgeons (ASES) scores was also comparatively assessed. Two hundred and two patients (101 per group) with GHOA and B2 or B3 glenoids were included in the 1:1 matched analysis. Mean and standard deviation of follow-up was 39 ± 18.7 months. The cohorts were well-matched with no differences in gender, age, ASA, BMI, preoperative glenoid morphology (Walch), glenoid retroversion, or posterior subluxation (P > 0.05). RSA was associated with lower postoperative VAS pain (RSA 0.5; TSA 1.2, P=0.036), however, no other clinical differences in PROMs were found. Most patients in both groups (TSA 95.0%; RSA 98.0%, P=0.436) reached MCID, and 82% of TSA patients and 90% of RSA patients reached SCB (P=0.292). No significant differences were found in overall complication rate (P=0.781) and active range of motion with exception of internal rotation being worse in RSA (RSA 2.7 and 5.2; TSA 3.9 and 6.5, P<0.001). Baseplate loosening occurred in 2 RSA cases and 29 TSA cases had glenoid radiolucencies (P<0.001) with 3 grossly loose glenoid components. Primary RSA results in largely comparable short-term outcomes compared to TSA in patients with Walch B2 or B3 glenoid morphology. Both TSA and RSA provide substantial clinical benefits to patients with significant posterior glenoid wear.

Pyrolytic carbon head shoulder arthroplasty: CT scan glenoid bone modeling assessment and clinical results at 3-year follow-up

The aim of this study is to report the radiological glenoid modifications and clinical outcomes at 3 years mean follow-up of hemi shoulder arthroplasty (HA) with pyrocarbon (PYC) humeral head. Our hypothesis was that the PYC implants would provide good outcomes without major glenoid erosion. Additionally, we hypothesized that HA-PYC allowed for remodeling of the bone. Patients underwent HA with PyC humeral head for treatment of primary or secondary osteoarthritis, excluding post-traumatic cases. All patients had a Constant Score assessed preoperatively and at the last follow-up. Preoperative and postoperative computed tomography scans at the last follow-up were performed to achieve 3-dimensional reconstructions of the scapulae. Deformities of the glenoid surface were analyzed as a distance differential between postoperative and preoperative to investigate potential bone remodeling vs. glenoid erosion. The subluxation index (SLI) was measured. We included 41 patients implanted with a HA-PYC. Average age at the time of implant was 63.8 (40 to 79 years). All patients were followed for ≥2 years with an average follow-up of 36.3 months (24 to 60 months). Constant Scores increased from 34 at baseline to 80 at the last follow-up points on average (P<.01). Return to work rate was 100% and 96% had resumed their physical activity. Ten (77%) of the 13 patients with posterior head subluxation had normalized their SLI. Furthermore, no significant differences were detected between the individuals having corrected their posterior subluxation and the others (preoperative SLI between 0.45 and 0.55). Glenoid wear is less than 0.6 mm at 3 years mean follow-up, ie, 5 times less than metallic implants. A tendency to recenter the head in the anteroposterior plane was found in type B glenoid, without increased erosion of the glenoid, with very good clinical results. We did not find any difference according to age or glenoid type for clinical and radiological results. HA-PYCs give, in the short term, excellent clinical results in terms of pain and function. The development of a precise and objective measurement method has made it possible to demonstrate that the glenoid surface is the site of modifications that may be part of bone remodeling or progression of the osteoarthritis disease.

Pyrocarbon hemiarthroplasty of the shoulder: a systematic review and meta-analysis of clinical results.

Hemiarthroplasty is often considered in the setting of preserved glenoid cartilage given the high risk of revision associated with total shoulder arthroplasty. Pyrocarbon (PyC) has been used as an implant material that theoretically allows for formation of a neo-membrane that would act like cartilage to reduce glenoid wear. The purpose of this study was to evaluate the clinical outcomes, radiographic outcomes, revision rates, and complication rates in the existing literature on shoulder hemiarthroplasty using PyC. The MEDLINE, Embase, and Scopus databases were searched for articles relating to shoulder hemiarthroplasty using the terms "pyrocarbon" or "pyrolytic carbon." Abstracts and articles were screened against predefined inclusion and exclusion criteria, with a minimum of 24 months' follow-up required. Data on patient demographic characteristics, clinical outcome scores, complications, revision rates, and radiographic findings were recorded. Where appropriate, meta-analysis was performed. Twelve studies were selected for final inclusion, with a total of 536 patients. Among the studies reporting preoperative and postoperative range of motion (ROM), an overall improvement in ROM was observed. The mean Constant score was 70.9 points postoperatively, with a mean improvement of 36.2 points (n=359, 9 studies). Radiographically, 22.8% of patients (n=536, 8 studies) had evidence of glenoid erosion, 10.4% had changes in implant positioning, and 9.9% had tuberosity thinning. In addition, 1.5% of patients had radiographic subacromial space reduction, whereas 0.7% had an increase in tuberosity thickness. Across all studies, there was an 8.6% complication rate, with the most common cause being glenoid erosion (2.6%, n=14). There was an overall 7.7% revision rate (n=41), with 63% of revisions (n=26) undergoing conversion to reverse or total shoulder arthroplasty. PyC hemiarthroplasty shows overall improvements in ROM and patient-reported outcomes for patients. However, there remains concern for glenoid erosion on radiographic evaluation at minimum 2-year follow-up. Although preliminary studies have shown encouraging results, this systematic review emphasizes the need for longer-term follow-up studies with further radiographic evaluation of the severity of glenoid erosion and the association with functional outcomes and failure risk.

Pyrocarbon hemiarthroplasty and the shoulder: biomechanical and clinical results of an emerging treatment option.

While shoulder hemiarthroplasty is still used to treat young patients with shoulder pathology, the use of this procedure has substantially declined in recent years due to its significant complication profile. Glenoid wear with arthrosis is one of the major postoperative complications following shoulder hemiarthroplasty, and efforts to prevent this complication led many scientists to explore alternative weight-bearing surfaces on arthroplasty implants to decrease joint wear and improve patient outcomes. Pyrolytic carbon, or pyrocarbon, is a material that has better biocompatibility, survivorship, strength, and wear resistance compared to the materials used in traditional shoulder hemiarthroplasty. Pyrocarbon implants have been used in orthopedics for over 50 years; recently, their utility in shoulder hemiarthroplasty has garnered much interest. The purpose behind the use of pyrocarbon in shoulder hemiarthroplasty is to decrease the risk of progressive glenoid wear, especially in young active patients in whom joint preservation is important. Promising survivorship and outcomes have been demonstrated by recent studies, including limited glenoid wear following pyrocarbon hemiarthroplasty. Nevertheless, these clinical studies have been limited to relatively small case series with limited long-term follow-up. Accordingly, additional research and comparative studies need to be conducted in order to properly assess the therapeutic efficacy and value of pyrocarbon hemiarthroplasty.

The impact of glenoid parameters and implant overstuffing on functional outcomes of shoulder hemiarthroplasty in patients with glenohumeral joint arthritis.

The outcomes of shoulder hemiarthroplasty are highly dependent on the baseline glenoid morphology and the rotator cuff integrity. The objective of this study was to assess whether certain glenoid parameters and implant overstuffing are associated with worse clinical outcomes following shoulder hemiarthroplasty. We retrospectively reviewed 25 patients who underwent shoulder hemiarthroplasty for shoulder arthritis, with a mean follow-up of 5.3years. The baseline glenoid morphology, the glenoid wear rate, the proximal humeral head migration and implant overstuffing were evaluated radiologically in all patients. The radiological parameters were correlated with the functional outcomes. The Constant-Murley score, the ASES score, and the OSS score were significantly better for patients with a concentric baseline glenoid compared to those with an eccentric glenoid. The Constant-Murley score and the ASES score were also improved in patients without implant overstuffing compared to patients with implant overstuffing (p < 0.05). However, glenoid wear was not associated with worse functional outcomes (p = 0.23 for Constant-Murley score, p = 0.15 for ASES score and p = 0.27 for OSS score). Last, a worse Constant-Murley score was strongly correlated with proximal humeral head migration (p < 0.001), while worse ASES and OSS scores were moderately correlated with proximal humeral head migration (p < 0.001). Our findings indicate that the results of hemiarthroplasty can be improved through careful selection of patients upon the baseline glenoid type morphology and proper implant sizing to avoid implant overstuffing. Moreover, glenoid wear is not associated with worse clinical outcomes, therefore shoulder hemiarthroplasty should be reconsidered as an alternative in younger patients with shoulder arthritis.