Magnetic resonance imaging vs. two- and three-dimensional computed tomography scans for assessment of glenoid inclination and version

Background: The purpose of this study was to evaluate the impact of software updating on measurements of the glenoid inclination and version, along with humeral head subluxation performed by an automated 3D planning program. The hypothesis was that the software update could significantly modify the values of the glenoid inclination and version, as well as of the humeral head subluxation. Methods: A comprehensive pool of 76 shoulder computed tomography (CT) scans of patients who underwent total shoulder arthroplasty (TSA) or reverse total shoulder arthroplasty (RTSA) were analyzed with the automated program Blueprint in 2018 and again in 2020 after a software update. Results: A statistically significant difference of 8.1 ± 8.2 and 5.4 ± 7.8 (mean difference of −2.8 ± 5.0, p < 0.001) was indeed reached when comparing the mean glenoid inclination achieved with Blueprint 2018 and Blueprint 2020, respectively. The glenoid version, as well as the humeral head subluxation evaluations, were not significantly different between the two software versions, with mean values being −9.4 ± 8.9 and −9.0 ± 7.4 and 60.1 ± 12.6 and 61.8 ± 12.0, respectively (p = 0.708 and p = 0.115, respectively). In 22% of CT scans, the software update determined a variation of the glenoid inclination of more than 5° or 10°. Conclusion: The present study shows the software update of an automated preoperative planning program may significantly modify the values of glenoid inclination. Even though without a significant difference, variations were also found for the glenoid version and humeral head subluxation. Accordingly, these results should further advise surgeons to carefully and critically evaluate data acquired with automated software.

Two techniques exist from which all 3D preoperative planning software for total shoulder arthroplasty are based. One technique is based on measurements constructed on the mid-glenoid and scapular landmarks (Landmark). The second is an automated system using a best-fit sphere technique (Automated). The purpose was to compare glenoid measurements from the two techniques against a control computed tomography-derived 3D printed scapula. Computed tomography scans of osteoarthritic shoulders of 20 patients undergoing primary total shoulder arthroplasty were analyzed with both 3D planning software techniques. Measurements from a 3D printed scapula (Scapula) from the true 3D computed tomography scan served as controls. Glenoid version and inclination measurements from each group were blinded and reviewed. In 65% (Automated) and 45% (Landmark) of cases, either inclination or version varied by 5° or more versus 3D printed scapula. Significant variability in version differences compared to the scapula group existed (p = 0.007). Glenoid version from the Scapula = 13.0° ± 10.6°, Automated = 15.0° ± 13.9°, and Landmark = 12.2° ± 7.8°. Inclination from Scapula = 5.4° ± 7.9°, Automated = 6.1° ± 12.6°, and Landmark = 6.2° ± 9.1°. A high percentage of cases showed discrepancies in glenoid inclination and version values from both techniques. Surgeons should be aware that regardless of software technique, there is variability compared to measurements from a control 3D computed tomography printed scapula.

Glenoid size, inclination, and version: An anatomic study

Comparison of two-dimensional manual and three-dimensional SurgiCase and BLUEPRINT planning software measurements of glenoid version, inclination, and humeral subluxation

The aim of this study was to evaluate glenohumeral morphologic differences and their correlation between glenohumeral instability and rotator cuff pathology. Two-hundred radiographs and 100 MRI scans of 100 patients in whom the diagnosis of Anterior Shoulder Instability (Anl) or Rotator Cuff Tear (RCT) was arthroscopically verified were retrospectively identified and included in the study. All the patients were categorized into two groups: 50 patients with Anl (23 female, 28 male; mean age = 29 ± 7.4) and 50 patients with RCT (28 female, 22 male). Two separate control groups were then formed, one of which included contralateral shoulders of patients in the AnI group, and the other consisted of contralateral shoulders of patients in the RCT group. The x-ray and MRI scans were examined by an orthopedic surgeon and a radiologist. The Acromial Index (AI) and the Critical Shoulder Angle (CSA) were measured on true anteroposterior shoulder radiographs; Glenoid Inclination (GI), Glenoid Version (GV), and Acromion Angulation (AA) were measured on MRI. In the AnI group, the measurements were as followed: AI, 0.66 ± 0.03; CSA, 33 ° ± 2.85; GI, 3.4° ± 6.2; GV, 4.1 ± 4.3; and AA, 12.9 ± 8.3. In the RCT group, AI 0.71 ± 0.04; CSA, 36° ± 2.69; GI, 9.1 ± 5; GV, 6.7 ° ± 5.7; and AA, 14.3° ± 8.7. A moderate correlation was found between CSA and GI (r = 0.41, P = 0.001) and between AI and GI (r = 0.42, P = 0.014). A weak correlation was found between AI and GI in the AnI group (r = 0.22, P = 0.001). The inter- and intra-observer intraclass correlation coefficients were respectively 0.81 and 0.84 for AI, 0.88 and 0.92 for CSA, 0.72 and 0.76 for GI, 0.69 and 0.73 for GV, and 0.72 and 0.77 for AA. The results of this study have shown that lower AI, GI, and antevert GV may be associated with AnI. Investigating CSA, AI, and GV could be useful for diagnostic evaluation of patients with AnI. Level III, Diagnostic Study.

Variations in glenoid morphology among patients of different gender, body habitus, and ethnicity have been of interest for surgeons. Understanding these anatomical variations is a critical step in restoring normal glenohumeral structure during shoulder reconstruction surgery. Retrospective review of 108 patient shoulder CT scans was performed and glenoid version, AP diameter and height were measured. Statistical multiple regression models were used to investigate the ability of gender and ethnicity to predict glenoid AP diameter, height, and version independently of patient weight and height. The mean glenoid AP diameter was 24.7 ± 3.5, the mean glenoid height was 31.7 ± 3.7, and the mean glenoid version was 0.05 ± 9.05. According to our regression models, males would be expected to exhibit 8.4° more glenoid retroversion than females (p = 0.003) and have 2.9mm larger glenoid height compared to females (p = 0.002). The predicted male glenoid AP diameter was 3.4mm higher than that in females (p < 0.001). Hispanics demonstrated 6.4° more glenoid anteversion compared to African-Americans (p = 0.04). Asians exhibited 4.1mm smaller glenoid AP diameters than African-Americans (p = 0.002). An increase of 25kg in patient weight resulted in 1mm increase in AP diameter (p = 0.01). Gender is the strongest independent predictor of glenoid size and version. Males exhibited a larger size and more retroverted glenoid. Patient height was found to be predictive of glenoid size only in patients of the same gender. Although variations in glenoid size and version are observed among ethnicities, larger sample size ethnic groups will be necessary to explore the precise relations. Surgeons should consider gender and ethnic variations in the pre-operative planning and surgical restoration of the native glenohumeral relationship. Anatomic Study.

BackgroundMalalignment of the humeral and glenoid components in total shoulder arthroplasty is associated with complications such as instability, implant loosening, and restricted motion. While the accuracy of patient-specific instrumentation (PSI) for glenoid component orientation is well documented, the precision of PSI for humeral osteotomy has not yet been published for a noncadaveric environment. This study aims to calculate the deviation between the planned and achieved orientations of humeral and glenoid components using PSI in a clinical, in vivo setting.MethodsForty-six patients were enrolled. One patient was excluded due to an intraoperative change to humeral component selection. The gender, etiology for arthroplasty (osteoarthritis or cuff tear arthropathy), severity of glenoid wear based on the Walch classification, and procedure (anatomic or reverse) were recorded. Computed tomography (CT) scans were obtained preoperatively for 3-dimensional reconstruction, from which the target humeral and glenoid component orientations for each patient were selected by the surgeon in the ASTRA surgical planning platform (Enovis, Austin, TX, USA). Humeral and glenoid PSIs were designed and 3-dimensionally printed to execute the planned alignments. A postoperative CT scan was acquired and used to calculate the deviation between the planned and achieved humeral version, humeral neck-shaft angle, humeral osteotomy height, glenoid version, and glenoid inclination. Humeral version was able to be calculated for 22 patients (48.9%) with a CT scan which extended distally beyond the humeral epicondyles.ResultsA total of 8 outliers (17.8%) were identified across all orientation parameters: 5 outliers (11.1%) for humeral orientation and 3 (6.7%) for glenoid orientation. The average deviation was 2.9°, 2.2°, 1.3 mm, 1.7° and 1.4° for humeral version, humeral neck-shaft angle, humeral osteotomy height, glenoid version, and glenoid inclination, respectively. The mean deviation in glenoid version was greater in males than females (P = .007). However, no other statistically significant difference was found between the mean or variance in deviation when comparing cohorts stratified by etiology of arthroplasty, severity of glenoid wear, or surgical procedure.ConclusionPSI generated from CT-based planning can achieve precise execution of preoperative plans in 89% of humeral and 93% of glenoid components in both anatomic and reverse procedures across a variety of patient morphologies. The humeral guide, when used in a more challenging in vivo environment, demonstrates accuracy comparable to those observed in existing ex vivo studies.

Background: Several researchers have investigated the angles of Glenoid version and Humerus head version worldwide, however sparsely studied in India. The purpose of the study was to determine the native angles of Glenoid and Humerus head version of adult skeletons and to compare the observation with the findings of other workers in different races while discussing our finding in light of literature. This data would prove of great assistance at the time of actual shoulder replacement surgery for proper alignment and fixation of the implants, as any variance from normal version would alter gleno-humeral mechanics and may predispose to instability and arthropathy. Materials and method: A total of sixty seven adult wet scapulae and sixty three humeri were harvested from cadavers fixed in formalin from the Department of Anatomy BJGMC, Pune. The angles of glenoid and humeral head version were measured using goniometer and compass. Correlation analysis was performed between humeral head version and glenoid version values. Result: This study finds wide distribution of glenoid version ranging from -10o to +6o the mean glenoid version of the left side (n=34) was -1.00±4.06o and on the right side (n=33) was -3.30±3.63o the average humerus version recorded on left (n=31) and the right (n=32) sides were 36.13±7.61o and 37.56±7.8o respectively. Conclusion: We report a significant difference between the mean value of the glenoid version angle of both sides; right being greatly retroverted. A significant positive. Correlation was established between Glenoid version and Humerus head version on the right side. Keywords: Humerus head Version, Glenoid Version, Arthroplasty, Retroversion, Glenoid fossa

Proper glenoid position in total shoulder arthroplasty (TSA) is important. However, traditional glenoid version (GV) measurements overestimate retroversion on radiographs (XR) and computed tomography (CT).The fulcrum axis (FA) uses palpable surface landmarks and may be useful as an intra-operative guide. Also, the FA has not yet been validated on XR or CT in an arthritic population. Four observers measured FA and GV on the XR, CT and three-dimensional CT (3DCT) of 40 patients who underwent TSA at a single institution from 2009 to 2015. Reliability and accuracy of FA and GV were calculated for XR and CT, using 3DCT as the gold standard. The mean FA and GV were 7.768° and 18.910° on XR; 6.23° and 12.920° on CT; and 8.100° and 7.740° on 3DCT, respectively. FA and GV were significantly different for XR and CT (p < 0.001) but not for 3DCT (p = 0.725). The inter-rater reliability, intra-rater reliability and accuracy of FA were not significantly different from GV and were 0.929 to 0.948, 0.779 to 0.974 and 0.674 to 0.705, respectively. However, the absolute difference of FA was closer to the gold standard (3DCT) than GV for XR (0.330° versus 11.172°) and CT (1.871° versus 5.178°) (p < 0.001). FA showed comparable reliability and accuracy to GV. However, FA more accurately reflected the gold standard.

Nearly 20% of Total knee Arthroplasty patients remain dissatisfied. This is a major concern in twenty-first century arthroplasty practice. Accurate implant sizing is shown to improve the implant survival, knee balance and patient reported outcome. Aim of the current study is to assess the efficacy of pre-operative three-dimensional (3D) CT scan templating in a robot-assisted TKA in predicting the correct implant sizes and alignment. Prospectively collected data in a single center from 30 RA-TKAswas assessed. Inclusion criterion was patients with end stage arthritis (both osteoarthritis and rheumatoid arthritis) undergoing primary TKA. Patients undergoing revision TKA and patients not willing to participate in the study were excluded. Preliminary study of ten patients had indicated almost 100% accuracy in determining the implant size and position. Sample size was estimated to be 28 for 90% reduction in implant size and position error with α error of 0.05 and beta error of 0.20 with power of study being 80. Post-operative radiographs were assessed by an independent observer with respect to implant size and position. The accuracy of femoral and tibial component sizing in the study was compared with the historic control with Chi-squared test. The p value < 0.05 was considered significant. The pre-operative CT scan 3D templating accuracy was 100% (30 out of 30 knees) for femoral component and 96.67% (29 out of 30 knees) for tibial component. The implant position and limb alignment was accurate in 100% of patients. The accuracy of femoral component and tibial component sizing is statistically significant (Chi-squared test, p value 0.0105 and 0.0461, respectively). The study results show the effectiveness of pre-operative 3 D CT scan planning in predicting the implant sizes and implant positioning. This may have a potential to improve the implant longevity, clinical outcomes and patient satisfaction.

To investigate the relationship between glenoid inclination or version and supraspinatus tendon full-thickness tears. Forty-two cases of unilateral supraspinatus tendon full-thickness tears were confirmed by clinical examinations and MRI scans. The bilateral glenoid inclination and version angles, measured by the volume rendering technique (VRT) and multi-planar reformation (MPR) of multi-slice computed tomography (MSCT) under 16-slice spiral CT scans, were compared by paired t test in all cases. The average inclination angle was (97.6 ± 4.0)° and (96.1 ± 2.9) at affected and healthy sides respectively. And the difference had statistical significance (P = 0.001); the average version angle was (-3.2 ± 5.0)° and (-3.1 ± 4.7)° at affected and healthy sides respectively. And the difference had no statistical significance (P = 0.79). The glenoid inclination angles are correlated with supraspinatus tendon full thickness tears while but the glenoid version angles are not. A larger glenoid inclination angle may be a positive predictive factor of supraspinatus tendon full-thickness tears.

Introduction: Anatomic shoulder arthroplasty for end-stage glenohumeral arthritis offers excellent outcomes for many patients. Computed tomography (CT) has become recognized as a valuable preoperative planning tool for assessing acquired bone deficiencies, such as excessive posterior glenoid version. It remains uncertain whether three-dimensional (3D) CT technology helps surgeons reliably restore native glenoid version and if version correction offers superior short-term clinical outcomes. Methods: Fifty consecutive patients undergoing anatomic shoulder arthroplasty were enrolled in this study. A preoperative CT scan with 3D planning software was used to restore a normal range of glenoid version (0 to 10 degrees retroversion). All patients received a pegged cemented glenoid polyethylene component and underwent a postoperative CT scan to evaluate component alignment and glenoid version. Outcomes were measured by the ASES (American Shoulder and Elbow Surgeons) shoulder score and PROMIS (Patient-Reported Outcomes Measurement Information System) Global Health survey at baseline, 14 weeks, one year, and two years. Results: Using the conventional radiological reading method, 76% of patients had their glenoid version corrected to 0-10°. Nearly all postoperative measures significantly improved at two-year follow-up, including pain, pain medication consumption, and range of motion. There were no statistically significant differences in patient outcomes when comparing glenoid version within versus outside the normal glenoid version correction range. Conclusion: Restoring near-anatomic glenoid version is believed to be an important step to maximize prosthetic longevity. Three-dimensional CT planning software offers ways to recognize and correct abnormal versions. In the study cohort, approximately three in four patients were corrected to normal levels. There was no statistical difference in short-term surgical outcomes within or outside the desired version range. Level of evidence: Level IV.

Effect of Sagittal Rotation on Axial Glenoid Width and Version: CT Scan Analysis in the setting of Anterior Bone Loss

The three-dimensional glenoid vault model can estimate normal glenoid version in osteoarthritis

Magnetic resonance imaging is comparable to computed tomography for determination of glenoid version but does not accurately distinguish between Walch B2 and C classifications