Lateralising reverse shoulder arthroplasty using bony increased offset (BIO-RSA) or increasing glenoid component diameter: comparison of clinical, radiographic and patient reported outcomes in a matched cohort.

BACKGROUND: This study aims to compare the range of motion (ROM) of reverse shoulder arthroplasty lateralised by bony increased offset (BIO-RSA) using a standard 38-mm (mm) component to regular reverse shoulder arthroplasty (RSA) lateralised by using a 42-mm glenoid component. The secondary aims are to compare patient-reported and radiographic outcomes between the two groups. MATERIALS AND METHODS: All patients with a BIO-RSA and size 38 glenosphere were retrospectively identified and matched to patients with a regular RSA and size 42 glenosphere. Matched patients were invited for a follow-up visit. ROM was assessed as well as radiographic outcomes (lateralisation, distalisation, inferior overhang, scapular notching, heterotopic bone formation, radiolucency, stress shielding, bone graft healing and viability and complications) and patient-reported outcomes (subjective shoulder value, Constant score, American Shoulder and Elbow Surgeons, activities of daily living which require internal rotation, activities of daily living which require external rotation and a visual analogue scale for pain). Outcomes were compared between the two groups. RESULTS: In total, 38 BIO-RSAs with a size 38 glenosphere were matched to 38 regular RSAs with a size 42 glenosphere. Of the 76 matched patients, 74 could be contacted and 70 (95%) were included. At the final follow-up, there were no differences between the two groups in ROM, patient-reported outcomes or radiographic outcomes (p > 0.485). CONCLUSIONS: Using a larger glenosphere is a feasible alternative to BIO-RSA for lateralising RSA, providing comparable ROM, patient-reported and radiographic results, while potentially decreasing costs, operative time and complication rates.

Scapula fractures: functional anatomy, clinical assessment and management.

Fractures of the scapula are rare injuries, accounting for 3-5% of all shoulder girdle fractures. They are frequently the result of high energy trauma and often present with concurrent and life-threatening injuries to adjacent structures, leading to significant morbidity and mortality. Patients presenting with scapula fractures must receive a thorough and systematic clinical assessment as directed by national trauma guidelines. Appropriate imaging is essential in delineating fracture morphology and should at the very least include anteroposterior, anteroposterior oblique (Grashey) and axillary or scapula 'Y' view of the shoulder. Computed tomography imaging with three-dimensional reconstruction allows better delineation of the fracture morphology and helps with surgical planning. A lack of randomised controlled trials comparing the efficacy of conservative and operative management of scapula fractures has resulted in limited consensus for surgical indications. Nevertheless, most extra-articular fractures can be managed conservatively while intra-articular fractures of the glenoid frequently require surgical fixation.

Minimum 5-Year Clinical and Return-to-Sport Outcomes After Primary Arthroscopic Scapulothoracic Bursectomy and Partial Scapulectomy for Snapping Scapula Syndrome.

BACKGROUND: Snapping scapula syndrome (SSS) is a rare condition that is oftentimes debilitating. For patients whose symptoms are resistant to nonoperative treatment, arthroscopic surgery may offer relief. Because of the rarity of SSS, reports of clinical outcomes after arthroscopic SSS surgery are primarily limited to small case series and short-term follow-up studies. PURPOSE: To report minimum 5-year clinical and sport-specific outcomes after arthroscopic bursectomy and partial scapulectomy for SSS and to identify demographic and clinical factors at baseline associated with clinical outcomes at minimum 5-year follow-up. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Patients who underwent arthroscopic bursectomy and partial scapulectomy for SSS between October 2005 and February 2016 with a minimum of 5 years of postoperative follow-up were enrolled in this single-center study. Clinical outcome scores, including the 12-Item Short Form Health Survey (SF-12), American Shoulder and Elbow Surgeons (ASES) Shoulder Score, shortened version of the Disabilities of the Arm, Shoulder and Hand (QuickDASH) score, Single Assessment Numeric Evaluation (SANE), and visual analog scale (VAS) score for pain, were collected at a minimum 5-year follow-up. Additionally, it was determined which patients reached the minimal clinically important difference. Bivariate analysis was used to determine whether baseline demographic and clinical factors had any association with the outcome scores. RESULTS: Of 81 patients eligible for inclusion in the study, follow-up was obtained for 66 patients (age 33.6 ± 13.3 years; 31 female). At a mean follow-up of 8.9 ± 2.5 years (range, 5.0-15.4 years), all of the outcome scores significantly improved compared with baseline. These included the ASES (from 56.7 ± 14.5 at baseline to 87.2 ± 13.9 at follow-up; P < .001), QuickDASH (from 38.7 ± 17.6 to 13.1 ± 14.6; P < .001), SANE (from 52.4 ± 21.2 to 82.7 ± 19.9; P < .001), SF-12 Physical Component Summary (from 39.7 ± 8.3 to 50.3 ± 8.2; P < .001), SF-12 Mental Component Summary (from 48.2 ± 11.7 to 52.0 ± 9.0; P = 0.014) and VAS pain (from 5.2 ± 2.1 to 1.4 ± 2.0; P < .001). The minimal clinically important difference in the ASES score was reached by 77.6% of the patients. Median postoperative satisfaction was 8 out of 10. It was found that 90.5% of the patients returned to sport, with 73.8% of the patients able to return to their preinjury level. At the time of final follow-up, 8 (12.1%) patients had undergone revision surgery for recurrent SSS symptoms. Older age at surgery (P = .044), lower preoperative SF-12 Mental Component Summary score (P = .008), lower preoperative ASES score (P = .019), and increased preoperative VAS pain score (P = .016) were significantly associated with not achieving a Patient Acceptable Symptom State on the ASES score. CONCLUSION: Patients undergoing arthroscopic bursectomy and partial scapulectomy for SSS experienced clinically significant improvements in functional scores, pain, and quality of life, which were sustained at a minimum of 5 years and a mean follow-up of 8.9 years postoperatively. Higher patient age, inferior mental health status, increased shoulder pain, and lower ASES scores at baseline were significantly associated with worse postoperative outcomes.

The latissimus dorsi creates a dynamic track for the inferior angle of the scapula during arm abduction in humans.

BACKGROUND: The importance of several scapulothoracic muscles, including trapezius and serratus anterior, in maintaining physiological scapula kinematics has been highlighted in the past. However, the relationship between the scapula and the latissimus dorsi muscle remains unclear. Our clinical surgical observation is that the latissimus dorsi does not directly attach but rather runs superficial to the inferior angle of the scapula. Based on this observation, we hypothesise that the latissimus dorsi creates a dynamic track on which the scapula glides under the muscle belly during elevation of the arm, creating the latissimus-scapula overlap (LSO). METHODS: All consecutive patients who had a whole-body computed tomography scan (CT) in case of polytrauma evaluation between 2018 and 2021, with complete depiction of the scapula and latissimus dorsi muscle, were analysed. 150 shoulders in 90 patients with arms up were matched according to their age (within five years), gender, and affected side with 150 shoulders in 88 patients with arms down. Patients with pathologies of the upper extremities or thorax that potentially could alter LSO measurements were excluded. LSO was calculated as a ratio of the measured area of the latissimus dorsi projection on the scapula and the total scapula area. RESULTS: The mean age of the 178 patients (48 females; 13 males) was 60 years. The arms-up group showed a significantly higher LSO than the arms-down group (19.9 ± 6.3% vs. 2.7 ± 2.2%; p < 0.0001). In the arms-up group, approximately one fifth of the scapula was overlapped inferiorly by the muscle belly of the latissimus dorsi, contrary to the almost non-existing LSO in the arms-down group. CONCLUSION: With arms up, humans show a significantly higher LSO in comparison to arms down indicating that the latissimus dorsi indeed creates a dynamic track on which the scapula is forced to travel during abduction of the arm. This finding of increased LSO during the elevation of the arm warrants further consideration of the role of the latissimus dorsi in scapula kinematics and potentially scapular dyskinesis. LEVEL OF EVIDENCE: Level two diagnostic study.

Posterior deltoid-sparing approach for displaced inferior or posterior glenoid fossa fractures: technical note and case series.

Scapular surgery has usually been performed through the posterior Judet approach. This approach allows access to the entire posterior scapular body, but causes significant soft tissue damage and detaches the deltoid muscle. To date, there has been no clinical study of a deltoid-preserving approach to access the joint for displaced postero-inferior glenoid fractures (Ideberg type II or Ib). We describe an easy and less invasive approach to the postero-inferior glenoid fossa.

Efficacy and safety of the Latarjet procedure for the treatment of athletes with glenoid bone defects ≥ 20%: a single-arm meta-analysis.

BACKGROUND: The shoulder joint is the most commonly dislocated joint in the human body, and the recurrence rate exceeds 50% after nonsurgical treatment. Although surgical treatment reduces the recurrence rate, there is controversy regarding the optimal surgical approach. Previous studies suggest that the Latarjet procedure yields favourable outcomes for specific populations at risk of recurrence, such as competitive athletes with significant glenoid defects. However, most of the existing related research consists of nonrandomized controlled trials with small sample sizes, and there is a lack of strong evidence regarding the efficacy and safety of the Latarjet procedure. METHODS: The PubMed, Embase, Cochrane Library, and Web of Science databases were systematically searched. Athletes with ≥ 20% glenoid defects were selected for inclusion. The following data were extracted: general patient information, instability rates, return to sports (RTS) rates, imaging features (graft positioning rate and graft healing rate), functional assessments [Rowe score, Athletic Shoulder Outcome Scoring System(ASOSS), visual analogue scale (VAS), forward flexion function, and external rotation function], and complications. RESULTS: After excluding suspected duplicate cases, a total of 5 studies were included in this meta-analysis. The studies involved a total of 255 patients, including 237 males (93%) and 18 females (7%). The average age at the time of surgery was 25.4 ± 8.5 years. All the studies had a minimum follow-up period of 2 years, with an average follow-up time of 48.7 ± 18.9 months. The pooled rate of return to sport (RTS) was 94.3% (95% CI: 87.3%, 98.8%), and 86.1% (95% CI: 78.2%, 92.5%) of patients returned to their preoperative level of activity. The pooled redislocation rate was 1.1% (95% CI: 0%, 3.8%). Regarding the imaging results, the combined graft retention rate was 92.1% (95% CI: 88.1%, 95.5%), and the graft healing rate was 92.1% (95% CI: 88%, 95.4%). Postoperative functional evaluation revealed that the combined Rowe score, ASOSS score, and VAS score were 93.7 ± 6.5 points, 88.5 ± 4.4 points, and 1.1 ± 10 points, respectively. The forward flexion and external rotation angles were 170.9 ± 6.9 degrees and 65.6 ± 4.5 degrees, respectively. After excluding one study with unclear complications, the combined complication rate was 9.4% (95% CI: 1.0%, 23.6%). CONCLUSION: For athletes with shoulder instability and a total of ≥ 20% glenoid bone defects, the Latarjet procedure can achieve excellent functional outcomes, with the majority of patients returning to preoperative levels of sports activity. This procedure also leads to a low recurrence rate. Therefore, the Latarjet procedure has been proven to be a safe and effective treatment.

Risk of suprascapular nerve injury in open Trillat procedure: an anatomical study.

PURPOSE: The open Trillat Procedure described to treat recurrent shoulder instability, has a renewed interest with the advent of arthroscopy. The suprascapular nerve (SSN) is theoretically at risk during the drilling of the scapula near the spinoglenoid notch. The purpose of this study was to assess the relationship between the screw securing the coracoid transfer and the SSN during open Trillat Procedure and define a safe zone for the SSN. METHODS: In this anatomical study, an open Trillat Procedure was performed on ten shoulders specimens. The coracoid was fixed by a screw after partial osteotomy and antero-posterior drilling of the scapular neck. The SSN was dissected with identification of the screw. We measured the distances SSN-screw (distance 1) and SSN-glenoid rim (distance 2). In axial plane, we measured the angles between the glenoid plane and the screw (α angle) and between the glenoid plane and the SSN (ß angle). RESULTS: The mean distance SSN-screw was 8.8 mm +/-5.4 (0-15). Mean α angle was 11°+/-2.4 (8-15). Mean ß angle was 22°+/-6.7 (12-30). No macroscopic lesion of the SSN was recorded but in 20% (2 cases), the screw was in contact with the nerve. In both cases, the ß angle was measured at 12°. CONCLUSION: During the open Trillat Procedure, the SSN can be injured due to its anatomical location. Placement of the screw should be within 10° of the glenoid plane to minimize the risk of SSN injury and could require the use of a specific guide or arthroscopic-assisted surgery.

Treatment options and outcomes for delayed scapular anatomical neck fractures: a case report and review of the literature.

INTRODUCTION: Scapular anatomical neck fractures are among the most infrequent shoulder girdle fractures. Only seven radiologically confirmed cases of scapular anatomical neck fractures have been documented in the literature to date, of which only one case underwent delayed surgery. CASE PRESENTATION: A 34-year-old male Persian patient with morbid obesity was diagnosed with a scapula anatomical neck fracture after a motor vehicle collision. The radiographic assessment of the patient indicated an increase in the scapular glenopolar angle (73.9°). Due to concurrent chest and head injuries, surgical intervention was deferred until 6 weeks following the injury. The posterolateral limited Dupont-Evrard approach was used because of the patient's extremely high body mass index. Two plates were utilized to achieve stable fixation of the glenoid neck fracture. Following a 1 year follow-up period, complete fracture union was successfully attained, resulting in a constant score of 79. CONCLUSIONS: The most accurate radiographic indicators of these fractures are a superior fracture line located laterally to the coracoid process, a small inferior spike, and an elevated glenopolar angle. The only tendon attached to the glenoid is the long head of the triceps, making these fractures unstable; therefore, surgery is required in the majority of instances. The small size of the fractured component makes stabilization more difficult. Overall, anatomical scapular neck fractures are extremely uncommon and distinguished from other scapular fractures by their unique radiological and biomechanical characteristics. This case highlights the challenges encountered when managing scapular fractures in patients with morbid obesity. The delayed surgical intervention and the choice of surgical approach tailored to the patient's specific anatomical and physiological considerations proved to be effective in achieving a favorable outcome.

Use of scapular tip flaps in the reconstruction of head and neck defects: a systematic review and meta-analysis.

Scapular tip flaps (STF) may be used as an alternative to traditional methods of reconstruction of head and neck cancer (HNC) defects. This study aimed to establish the success and complication rates for STF in HNC reconstruction. A literature search was conducted on PubMed, BMJ Journals, DARE, EMBASE databases and Cochrane (CENTRAL) register. (Registry CRD42023428012). A total of 23 studies fulfilled the inclusion criteria with 474 patients who underwent reconstructive procedures using the STF. 100% of STF used were free flaps (STFFs). The most common reason for reconstruction was following malignancy (81.4%, n = 386). The pooled success rates in all studies using scapular tip flaps in head and neck reconstruction was 99% (95% CI, 97 to 100, p = 1.00; I2 = 0). Pooled total complication rates were 38% (95% CI, 25 to 51, p < 0.01; I2 = 90%). 19.6% required return to theatre with only 1.5% being for repeat flap coverage. The STF demonstrated an overall success rate of 99%. This is higher than other documented success rates with mainstay flaps for HNC defect reconstruction. Complication and re-operation rates were also like recorded rates. This review demonstrates the advantage of STF as a safe and versatile reconstructive option for HNC related defects. Evaluation of the literature is limited by poor-quality studies and comparability bias.

Virtual Surgical Guidance Improves Quality of Life Following Scapular Free-Flap Reconstruction of Maxillary Defects.

BACKGROUND: The best approach to maxillary reconstruction with negative impact on the patient's quality of life (QOL) remains the subject of debate. PURPOSE: This study was designed to evaluate the QOL outcomes following maxillary reconstruction using a scapular-free flap, with and without the computer-aided design and computer-aided manufacturing (CAD/CAM) technique. STUDY DESIGN, SETTING, SAMPLE: A prospective randomized controlled clinical trial was performed following the CONSORT checklist. To be included, patients suffering from maxillary defects without previous surgery or lymph node involvement were selected. Patients with poor oncological prognosis, deficient performance status, preoperative chemotherapy, or radiotherapy, besides vascular contraindications, were excluded. PREDICTOR VARIABLE: The predictor variable was the reconstruction technique, grouped into two equal categories. Patients were randomly assigned to reconstruction with a scapular-free flap, with the control group not utilizing a guide and the study group utilizing a CAD/CAM-customized guide. MAIN OUTCOME VARIABLE: The primary outcome variable was the various domains of QOL, measured using the University of Washington Quality of Life score, 12 months after reconstruction. COVARIATES: Age; sex; scapular flap side; and maxillary defect tumour type, histopathology, side, length, class, sagittal, and axial differential areas were considered. ANALYSES: Shapiro-Wilk and Kolmogorov-Smirnov tests were performed for normality. For comparisons between the two groups, Student's t-test and Mann-Whitney test were used. The category variables were compared using the χ2 test. P ≤ .05 was considered statistically significant. RESULTS: The sample was composed of twenty-two eligible patients, eleven in each group. The mean age of the control group was (50.09 ± 17.14) years, and 45.45% were male, while in the study group, the mean age was (48.36 ± 14.14) years, with 36.36% male. All the patients were evaluated, showing statistically significant differences between control and study groups in terms of pain, appearance, chewing, swallowing, speech, and shoulder (P ≤ .05), indicating that the scapular-free flap with a CAD/CAM osteotomy guide had improved the patient's QOL. CONCLUSION AND RELEVANCE: The findings of this study indicate that virtual surgical planning with a CAD/CAM customized osteotomy guide using a scapular-free flap can improve QOL in maxillary reconstruction in terms of pain, appearance, chewing and swallowing food, pronouncing words, and shoulder QOL outcomes.

[Influencing factors on effectiveness of reverse total shoulder arthroplasty].

Objective: To summarize the influencing factors on the effectiveness of reverse total shoulder arthroplasty (RTSA), so as to provide reference for clinical treatment. Methods: The related research literature of RTSA at home and abroad was extensively consulted, and the factors that may affect the effectiveness were summarized from the aspects of surgical technique, muscle condition, general condition of patients, psychological expectation, and lifestyle. Results: For surgical techniques, different surgical approaches have their own advantages. The glenoid notch, poor bone ingrowth, increased bone resorption, and infection would lead to the loosening of glenoid prosthesis. In addition, the neck shaft angle and inclination angle of humeral prosthesis affect the occurrence of glenoid notch and the range of motion of joint internal/external rotation after operation, respectively. For muscle condition, the quality of teres minor and deltoid muscle has an important influence on joint stability after operation. Moderate increase of deltoid muscle tension can improve joint mobility after operation, and suture repair of subscapular tendon during operation can relieve joint pain and improve function, range of motion, and strength. For the general condition of patients, gender, age, and body mass index are all related to postoperative joint function and complications, and different occupations and postoperative exercise levels affect the recovery. The patients with severe degenerative diseases, poor preoperative function, and long disease duration have lower expectations and higher satisfaction with the effectiveness, and bad lifestyle has a negative impact on the effectiveness. Conclusion: The effectiveness of RTSA is related to surgical technique, muscle condition, general condition of patients, psychological expectation, and lifestyle. In order to avoid the loosening of glenoid prosthesis, the operator should choose humeral prosthesis with small neck shaft angle and large glenoid ball and put them down and inclined inferiorly during operation, and choose appropriate approach to eliminate space with drainage to reduce the risk of infection. After operation, patients should avoid activities that generate high anterior and posterior shear forces. In addition, the humeral prosthesis with a inclination angle of 10°-20° can achieve the best balance between the range of internal rotation and external rotation after operation. Proper deltoid tension can maintain joint stability and good range of motion. Suture of subscapular tendon is recommended.

Outcomes and influencing factors of dental implants in fibula, iliac crest, and scapula free flaps: a retrospective case-control study.

PURPOSE: Reconstruction with vascularized bone grafts after ablative surgery and subsequent dental rehabilitation with implants is often challenging; however, it helps improve the patient's quality of life. This retrospective case-control study aimed to determine the implant survival/success rates in different vascularized bone grafts and potential risk factors. METHODS: Only patients who received implants in free vascularized bone grafts between 2012 and 2020 were included. The free flap donor sites were the fibula, iliac crest, and scapula. The prosthetic restoration had to be completed, and the observation period had to be over one year after implantation. Implant success was defined according to the Health Scale for Dental Implants criteria. RESULTS: Sixty-two patients with 227 implants were included. The implant survival rate was 86.3% after an average of 48.7 months. The causes of implant loss were peri-implantitis (n = 24), insufficient osseointegration (n = 1), removal due to tumor recurrence (n = 1), and osteoradionecrosis (n = 5). Of all implants, 52.4% were classified as successful, 19.8% as compromised, and 27.8% as failed. Removal of osteosynthesis material prior to or concurrent with implant placement resulted in significantly better implant success than material not removed (p = 0.035). Localization of the graft in the mandibular region was associated with a significantly better implant survival (p = 0.034) and success (p = 0.002), also a higher Karnofsky Performance Status Scale score with better implant survival (p = 0.014). CONCLUSION: Implants placed in vascularized grafts showed acceptable survival rates despite the potential risk factors often present in these patient groups. However, peri-implantitis remains a challenge.

Scapular Osteotomy for Lateral Access to a T1-2 Foraminal Disc Extrusion, Treated by Mini-Hemilaminectomy in a Dog.

A 4-year-old female spayed French bulldog was presented with a 2-day history of neck pain and left thoracic limb lameness with no neurological deficits. A computed tomography (CT) examination showed a left foraminal T1-2 disc extrusion. Surgical management was performed using a left lateral approach to the vertebral column with a scapular osteotomy. A T1-2 mini-hemilaminectomy was performed. The scapular osteotomy was stabilized with two 2.4-mm locking compression plates. The postoperative CT and radiographic examinations showed adequate decompression of the T1-2 foramen and good reduction in the scapular osteotomy. The dog was able to walk the following day. At the 1-month follow-up, the dog had no neck pain but persistent slight left thoracic limb lameness. Ten months postoperatively, a CT scan showed no abnormalities at the surgical site, and the dog had no neurological deficits nor lameness. The aim of this case report was to describe a new lateral approach to T1-2 intervertebral space.

Congruent Concavity Restoration of the Reconstructed Glenoid After the Latarjet Procedure: Compensation for the Position of the Graft.

BACKGROUND: Few clinical studies have addressed concavity restoration by natural remodeling after a Latarjet procedure. This study investigated the fibrous tissue and osseous remodeling of the reconstructed glenoid and concavity restoration after a Latarjet procedure using postoperative computed tomographic arthrography (CTA). METHODS: This retrospective study included 31 patients who underwent immediate postoperative computed tomographic (CT) scanning followed by CTA at 6 months postoperatively. We investigated whether fibrous tissue was newly created over the graft, whether the created fibrous tissue restored the congruity of the articular surface and the osseous remodeling of the graft to the glenoid level (whether the osseous portion of the graft was remodeled flush to the glenoid level) and the concavity of the glenoid using the radius of a best-fit circle on the articular surface, and the relationship between the amount of created fibrous tissue and the position of the graft. RESULTS: In all patients, the fibrous tissue on the graft yielded a smooth articular surface, as revealed by the CTA. The mean radius of the entire glenoid, including the transferred graft, was significantly smaller (p = 0.010) at 33.2 ± 8.5 mm than that of the glenoid posterior to the osseous step-off at 37.6 ± 9.4 mm, which is presumed to be the glenoid before the surgical procedure. Despite the congruity of the articular surfaces due to fibrous tissue seen in the CTA, 14 (45%) of 31 patients showed a subchondral osseous step-off on either the medial side or the lateral side in the immediate postoperative CT scans. However, through osseous remodeling, 8 of the 10 grafts with a lateral step-off and 2 of the 4 grafts with a medial step-off converted to a flush position. The position of the step-off was correlated with the thickness of the fibrous tissue, with a tendency for thicker tissue in cases of a step-off on the medial side (p = 0.014). CONCLUSIONS: Fibrous tissue formation plus remodeling of the transferred graft resulted in the restoration of a congruent concavity after a Latarjet procedure by compensating for initially non-flush positioning of the graft. However, due to the small sample size in our study, clinical outcomes could not be correlated with radiographic findings, and our recommendation is to continue placing the graft as anatomically as possible. LEVEL OF EVIDENCE: Therapeutic Level IV . See Instructions for Authors for a complete description of levels of evidence.

3D-printed glenoid implant reconstruction, after partial scapulectomy for malignant tumors: a case series.

PURPOSE: Glenoid tumors are extremely rare, and reconstruction remains very challenging. The aim of this study is to present the clinical and functional outcomes, of a new glenoid reconstruction method using 3-dimensional-printed implant. METHODS: Four patients with primary glenoid tumors underwent reconstruction using 3-dimensional-printed glenoid implant linked with reverse shoulder arthroplasty. We retrospectively reviewed the clinical and functional outcome, using MSTS and DASH score, as well as complications' rate. RESULTS: Wide excision was achieved in all patients. No local recurrence or distant metastasis was diagnosed at the follow-up period. The mean MSTS score was 80.5%, and DASH score was 15.2%. According to Hendersons' classification, there were no postoperative complications. CONCLUSION: The use of 3-dimensional-printed implants, can be a very reliable solution with satisfying clinical and functional outcomes for reconstruction, in patients with musculoskeletal malignancies of the glenoid. Level of evidence IV Treatment Study.

Baseplate inferior offset affects shoulder range of motion in reverse shoulder arthroplasty in Asian population.

BACKGROUND: Impingement is a common complication of reverse shoulder arthroplasty. Placement of the baseplate with a wide impingement-free angle is ideal; however, there are few studies on Asian populations, which have smaller height and physique, and there is a lack of guidance on achieving optimal outcomes. The purpose of the present study was to explore the impingement-free range of motion reverse shoulder arthroplasty and analyze the suitable baseplate position or tilt for the Asian population using simulation software. METHODS: We uploaded computed tomography scan data from 20 Asian patients to three-dimensional (3D) simulation software. The implantation of the reverse shoulder arthroplasty component was performed on the 3D humerus and scapula using software, and range of motion was assessed until impingement occurred. RESULTS: The range of motion in flexion significantly improved when the baseplate was lowered up to 3 mm inferiorly. Range of motion in abduction and internal and external rotation significantly improved as the baseplate was lowered up to 4 mm. There was no significant difference in range of motion in any motion after changing the inferior tilt, except in internal and external rotation. CONCLUSIONS: The range of motion in abduction, flexion, and internal and external rotations significantly improved with increased inferior offset. These results may prove valuable in determining the optimal baseplate position for RSA, particularly in Asian populations.

Acromion fractures after reverse shoulder arthroplasty occur in predictable clusters.

BACKGROUND: Acromion and scapular spine fractures (ASFs) following reverse total shoulder arthroplasty (RSA) have been reported at a rate of 3.9%. The location of the fracture has been shown to be an important factor in determining the outcomes of nonoperative treatment, with medial fractures having worse outcomes than lateral fractures. As the debate between operative and nonoperative treatment continues, a more precise understanding of the location of the fracture is necessary for effective management. The purpose of this study was to use 3-dimensional computed tomography (CT) reconstruction to characterize the exact location of ASFs after RSA. METHODS: A retrospective review of 2 separate institutional shoulder and elbow repositories was performed. Patients with post-RSA ASFs documented by post-fracture CT scans were included. The query identified 48 patients who sustained postoperative ASFs after RSA between July 2008 and September 2021. CT scans of patients with ASFs were segmented using Mimics software. Eight patients were excluded because of poor image quality. Each bone model was manipulated using 3-Matic Medical software to align the individual scapula with an idealized bone model to create a view of scapular fracture locations on a normalized bone model. This model was used to classify the fractures using the modified Levy classification. RESULTS: The study cohort consisted of 40 patients with a diagnosis of postoperative ASF after RSA. The median age at the time of surgery was 76 years (interquartile range, 73-79 years). The cohort comprised 32 women (80%) and 8 men (20%), with a median body mass index of 27.8. Only 10 patients (25%) had a previous diagnosis of osteoporosis and 6 (13%) had a diagnosis of inflammatory arthritis; 53% of patients underwent RSA owing to rotator cuff tear arthropathy. The distribution of fracture locations was similar within the cohort. However, lateral fractures were slightly more prevalent. The most common fracture location was the type I zone, with 12 fracture lines (29%). There were 11 fracture lines (26%) in the type IIa zone, 10 (23%) in the type IIb zone, 0 in the type IIc zone, and 9 (21%) in the type III zone. CONCLUSION: ASFs after RSA occur in 4 predictable clusters. No fractures appeared to distinctly cluster in the type IIc zone, which may not represent a true fracture zone. Understanding the distribution of these fractures will help to enable the future design of implants and devices to stabilize the fractures that require fixation.

Both angled bony-increased offset and metal-augmented baseplates provide satisfactory bone incorporation to the glenoid in reverse total shoulder arthroplasty: a radiographic evaluation using tomosynthesis.

BACKGROUND: Angled bony-increased offset and metal-augmented baseplate have recently been used to achieve neutral to inferior inclination of the glenoid implant. Nonetheless, bone incorporation is difficult to evaluate using computed tomography or other conventional methods owing to the presence of metal artifacts; therefore, whether bone incorporation between the grafted bone and glenoid or between the graft and baseplate implant can be achieved remains unclear. Several studies have reported the effectiveness of tomosynthesis in reducing metal artifacts for the evaluation of implant loosening, bone resorption, and spot welds. We aimed to evaluate and compare the bone incorporation rates between angled bony-increased offset and metal-augmented implants using tomosynthesis with metal artifact reduction technology. We hypothesized that a high bone incorporation rate would be obtained with angled bony-increased offset and a metal-augmented baseplate. METHODS: A total of 52 patients who underwent reverse total shoulder arthroplasty (TSA) with angled bony-increased offset and 42 patients who underwent reverse total shoulder arthroplasty with metal-augmented baseplate were assessed and followed up for a minimum of 2 years. The bone incorporation and implant loosening rates were compared between the 2 groups, and the sites of spot welds and trabeculation were recorded according to zones. Bone incorporation between the bone and prosthesis was defined as a confirmation of spot welds connecting the porous area and bone in more than three zones. Bone incorporation between the native bone and grafted bone was defined as an observation of trabeculation. Glenoid loosening was defined as the presence of at least 1 mm radiolucency around the prosthesis in more than 2 zones. RESULTS: Both the angled bony-increased offset and metal-augmented baseplate groups achieved sufficient bone incorporation rates (98% [51/52 cases] vs. 100% [42/42 cases], P = 1.0) and low implant loosening rates (2% [1/52 cases] vs. 0% [0/42 cases], P = 1.0). Spot welds and trabeculation were likely to be confirmed in the lower parts of the glenoid. CONCLUSION: The two groups did not show any significant differences regarding bone incorporation rates. Considering the complexity of performing the procedure with angled bony-increased offset, the use of a metal-augmented baseplate can serve as an alternative treatment to avoid superior inclination in reverse total shoulder arthroplasty.

Determining optimal length of coracoid graft in the modified Bristow procedure for anterior shoulder instability: A three-dimensional finite element analysis.

BACKGROUND: There is a lack of consensus concerning the coracoid graft length in the modified Bristow procedure. OBJECTIVE: We attempted to determine the optimal graft length using the three-dimensional finite element method. METHODS: In a shoulder model with a 25% anterior glenoid defect, a coracoid graft of varying lengths (5, 10, 15, and 20 mm) was fixed using a half-threaded screw. First, a compressive load of 500 N was applied to the screw head to determine the graft failure load during screw tightening. Next, a tensile load (200 N) was applied to the graft to determine the failure load due to biceps muscle traction. RESULTS: In the screw compression, the failure loads in the 5-, 10-, 15-, and 20-mm models were 252, 370, 377, and 331 N, respectively. In the tensile load applied to the coracoid graft, the failure load exceeded 200 N for both the 5- and 10-mm models. CONCLUSION: The 5-mm graft had a high risk of fracture during intraoperative screw tightening. As for the biceps muscle traction, the 5- and 10-mm-grafts had a lower failure risk than the 15- and 20-mm-grafts. Therefore, we believe that the optimal length of the coracoid graft is 10 mm in the modified Bristow procedure.