Primary retroperitoneal cavernous hemangioma: A case report and review of the literature.

Retroperitoneal cavernous hemangioma, a rare vascular tumor, has only 30 PubMed cases. Preoperative diagnostic criteria are unclear and often present asymptomatically until complications such as rupture or compression arise. We present a 73-year-old with chronic abdominal pain and a giant retroperitoneal tumor. Computed tomography (CT) and magnetic resonance imaging (MRI) revealed an irregular space-occupying mass in the retroperitoneum, suggesting a retroperitoneal chronic expanding hematoma. Total surgical resection confirmed the diagnosis as retroperitoneal cavernous hemangioma.

Identification of the female sex pheromone of Bastilla arctotaenia (Lepidoptera: Erebidae).

(3Z,6Z,9Z)-3,6,9-henicosatriene was identified as a major component of female sex pheromone of Bastilla arctotaenia (Lepidoptera: Erebidae), a pest of cultivated roses, by gas chromatograph-electroantennographic detector( GC-EAD) and gas chromatograph/mass spectrometry (GC/MS) analyses. The single (3Z,6Z,9Z)-3,6,9-henicosatriene (1.0 mg/lure) successfully attracted B. arctotaenia males in the field.

Valgus instability and related factors beyond 2 years following unlinked total elbow arthroplasty.

HYPOTHESIS AND BACKGROUND: Total elbow arthroplasty (TEA), categorized into linked and unlinked types, is a commonly reported treatment for rheumatoid arthritis of the elbow. Although unlinked TEA preserves bone, it may result in instability. This study aimed to assess the outcomes of unlinked TEA in rheumatoid arthritis of the elbow beyond 2 years and to identify factors correlating with postoperative valgus instability of unlinked TEA. METHODS: This study included patients who underwent TEA for rheumatoid arthritis of the elbow at our department between August 2009 and January 2017, with a follow-up period exceeding 2 years. Elbow joint range of motion (ROM) and clinical scores were evaluated preoperatively and at the final follow-up. Factors contributing to valgus instability, such as the Larsen grade, sex, age, side, preoperative ROM, postoperative ROM, implant placement, preoperative carrying angle, and the use of biological disease-modifying antirheumatic drugs (bDMARDs), were also assessed. RESULTS: This study encompassed 26 elbows from 23 patients, with a mean patient age at surgery of 64.8 years and a mean follow-up duration of 92.4 months. Significant improvements were observed in the ROM (extension: from -31° preoperatively to -21° postoperatively [P = .02], flexion: from 116° to137° [P < .001]), Japanese Orthopaedic Association-Japan Elbow Society Elbow Function Score (from 45.9 to 86.3 points [P < .001]), and Mayo Elbow Performance Score (from 43.6 to 91.7 points [P < .001]). At the last follow-up, 2 elbows exhibited radiolucent lines around the humeral stem, whereas 7 had valgus instability. Factors correlated with valgus instability included total arc at the final follow-up, preoperative carrying angle, and the use of bDMARDs. DISCUSSION AND CONCLUSION: Unlinked TEA demonstrated favorable midterm outcomes for rheumatoid arthritis of the elbow, albeit with occasional valgus instability. Surgeons should consider preoperative carrying angle and bDMARD use, and exercise caution regarding intraoperative extensions.

A Case of Floating Aortic Arch Thrombosis in a Patient without Thrombophilia.

Floating aortic arch thrombi-blood clots forming in an aorta without aneurysms or atherosclerosis-in a normal aorta are exceedingly rare. The etiology is unknown, and there are no guidelines for appropriate treatment strategies. We report a case of floating aortic arch thrombosis in a patient without coagulopathy that was treated surgically. As the mass could not be identified preoperatively as a tumor or thrombus, synthetic graft replacement was performed, allowing resection of the lesion site. Histopathological examination revealed erosion and fissures in the tunica intima of the aorta, which suggested vessel damage to the tunica intima as the cause.

Description and phylogenetic placement of a new species of Patania (Lepidoptera: Crambidae: Spilomelinae) resembling P. harutai (Inoue, 1955).

Patania harutai (Inoue, 1955) was known to be the mixture of two species that use host plants from two different families, Styracaceae and Sapindaceae, but the type materials had not been examined until now. In this study, we confirm the identity of P. harutai based on the adult external characters of the holotype. As a result, we regard the Sapindaceae-feeding species to be true P. harutai, and describe the Styracaceae-feeding species as a novel species, P. crepuscularia sp. nov. Patania gorosoe Lee, Heo & Bae, 2022 syn.n. is treated as a junior synonym of P. harutai. In addition, we conducted a molecular phylogenetic analysis using 10 Japanese Patania species, and found that P. crepuscularia and P. harutai are not sister species although they are very similar in the adult external characters.

Bilateral Humeral Retrotorsion Angle Measured Using an Ultrasound-Assisted Technique in Asian Baseball Players.

Background: Repetitive pitching is thought to restrict the physiological derotation process of the humeral head. Some studies have reported that side-to-side differences in the humeral retrotorsion angle (ΔHRA) occur between the ages of 9 and 11 years in baseball players. However, it remains unclear whether the ΔHRA in Asian baseball players depends on pitching skill or competitive level. Purpose: To evaluate the ΔHRA in Asian collegiate and professional baseball players and to determine the effects of pitching activity on the physiological derotation process of the humeral head. Study Design: Cross-sectional study; Level of evidence, 3. Methods: We evaluated 128 shoulders in 64 Asian baseball players who were stratified into 4 groups as follows: 13 professional pitchers; 9 professional fielders; 8 collegiate pitchers; and 34 collegiate fielders. The throwing and nonthrowing side HRA was assessed using an ultrasound-assisted technique, and the ΔHRA was compared among the 4 groups. In addition, Pearson correlation analysis was used to assess the relationship between ΔHRA and glenohumeral range of motion, baseball starting age, and fastball velocity in pitchers. Results: The HRA was significantly greater in the throwing arm than in the nonthrowing arm in each group, with no significant differences among the groups. There was no correlation between ΔHRA and range of motion or fastball velocity. There was a significant negative correlation between baseball starting age and ΔHRA in professional fielders (r = -0.633; P = .036). Conclusion: The findings of the present study provide evidence that in Asian baseball players, the HRA was significantly greater in the throwing arm than in the nonthrowing arm. There were no clear associations between HRA and pitching ability or competitive level.

Targeted amplicon sequencing of wastewater samples for detecting SARS-CoV-2 variants with high sensitivity and resolution.

Wastewater-based epidemiology (WBE) is a promising approach for monitoring the spread of SARS-CoV-2 within communities. Although qPCR-based WBE is powerful in that it allows quick and highly sensitive detection of this virus, it can provide limited information about which variants are responsible for the overall increase or decrease of this virus in sewage, and this hinders accurate risk assessments. To resolve this problem, we developed a next generation sequencing (NGS)-based method to determine the identity and composition of individual SARS-CoV-2 variants in wastewater samples. Combination and optimization of targeted amplicon-sequencing and nested PCR allowed detection of each variant with sensitivity comparable to that of qPCR. In addition, by targeting the receptor binding domain (RBD) of the S protein, which has mutations informative for variant classification, we could discriminate most variants of concern (VOC) and even sublineages of Omicron (BA.1, BA.2, BA.4/5, BA.2.75, BQ.1.1 and XBB.1). Focusing on a limited domain has a benefit of decreasing the sequencing reads. We applied this method to wastewater samples collected from a wastewater treatment plant in Kyoto city throughout 13 months (from January 2021 to February 2022) and successfully identified lineages of wild-type, alpha, delta, omicron BA.1 and BA.2 as well as their compositions in the samples. The transition of these variants was in good agreement with the epidemic situation reported in Kyoto city during that period based on clinical testing. These data indicate that our NGS-based method is useful for detecting and tracking emerging variants of SARS-CoV-2 in sewage samples. Coupled with the advantages of WBE, this method has the potential to serve as an efficient and low cost means for the community risk assessment of SARS-CoV-2 infection.

Light and heavy chain deposition disease with focal amyloid deposition diagnosed with mass spectrometry: a case report.

BACKGROUND: Light and heavy chain deposition disease (LHCDD) is a rare condition characterised by the deposition of immunoglobulin components in the kidneys. Similarly, Amyloidosis is also caused by the deposition of light chain and/or heavy chain components of immunoglobulins which are folded into amyloid fibrils characterised by Congophilic deposits that exhibit apple-green birefringence under polarised light. Only a handful of reports describing LHCDD with amyloid fibril deposition have been previously published, however, none have characterized the composition of the deposited immunoglobulin components via mass spectrometry. CASE PRESENTATION: We report a case of a 79-year-old Japanese woman with nephrotic syndrome. Bone marrow aspiration revealed a slight proliferation of plasma cells (under 10%). Immunofluorescence assessment of renal biopsy showed amyloid-like deposits in the glomerulus that were positive for IgA and kappa. Further, the Congo red staining of the deposits was faintly positive, and only a slight birefringence was detected. Electron microscopy confirmed fine fibrillar structures and non-amyloid deposits. Finally, mass spectrometry revealed that the deposits were composed of abundant amounts of light chain with small amounts of heavy chain. Therefore, the patient was diagnosed with LHCDD and focal amyloid deposition. Chemotherapy was subsequently initiated, which resulted in haematological and renal response. Under polarised light, faint birefringence with Congo red staining and periodic acid-methenamine silver positivity indicated that the deposits were mostly non-amyloid fibrils with a small component of amyloid fibrils. Generally, the diagnosis of heavy- and light-chain amyloidosis is defined by greater heavy chain deposition compared to the light chain. However, in our case, contrary to the definition, the light-chain deposition was far greater than that of the heavy-chain. CONCLUSIONS: This is the first case of LHCDD with focal amyloid deposition diagnosed by analysing the glomerular deposits by mass spectrometry.

Deep fibrous histiocytoma of the index finger: a case report.

Our patient presented with an elastic soft mass of his left index finger. Hematoxylin and eosin staining showed a high cellular density with spindle-shaped cells in a storiform pattern. Immunohistochemical staining was positive for CD68, factor XIIIa and α-smooth muscle actin, and negative for CD34, STAT6, S100 protein, and desmin.

The academic impact and value of an international online surgery lecture series.

Due to the worldwide travel restrictions caused by the 2019 coronavirus disease pandemic, many universities and students lost opportunities to engage in international exchange over the past 2 years. Teleconferencing systems have thus been developed to compensate for severe travel restrictions. Kansai Medical University in Japan and Vilnius University in Lithuania have a collaborative research and academic relationship. The two universities have been conducting an online joint international surgery lecture series for the medical students of both universities. Fifteen lectures were given from October 2021 to May 2022. The lectures focused on gastrointestinal surgery, gastroenterology, radiology, pathology, genetics, laboratory medicine, and organ transplantation. A survey of the attendees indicated that they were generally interested in the content and satisfied with attending this lecture series. Our efforts were successful in providing Japanese and Lithuanian medical students with the opportunity to engage in international exchange through lectures held in each other's countries.

Case report: administration of immune checkpoint inhibitor for SMARCB1 (INI1)-negative rhabdoid carcinoma with microsatellite instability (MSI)-high in the right colon.

BACKGROUND: Malignant tumors with rhabdoid features are rare, highly aggressive, and some of them are characterized by SMARCB1 (INI1) loss. Although cases of rhabdoid carcinoma are extremely rare, its occurrence in the colon has been reported previously. CASE PRESENTATION: A 71-year-old Japanese female patient presented with loss of appetite, fatigue, and weight loss. Computed tomography demonstrated a tumor in the right colon that infiltrated the surrounding kidneys and swelling of the left supraclavicular and periaortic lymph nodes. Laparotomy revealed that the tumor was unresectable because it had directly invaded the head of the pancreas and duodenum. Therefore, ileocecal vascularized bulky lymph nodes were sampled, and gastrojejunostomy with Braun's anastomosis and ileotransversostomy were performed as palliative procedures. Histopathological examination of the lymph nodes revealed that the neoplastic cells had rich eosinophilic cytoplasm and eccentrically located large nuclei characteristic of rhabdoid carcinoma. In addition, these neoplastic cells lacked SMARCB1 expression; therefore, the patient was diagnosed with SMARCB1-negative rhabdoid carcinoma. The postoperative course was uneventful. Molecular analysis confirmed that the neoplastic cells had high microsatellite instability (MSI); therefore, two cycles of pembrolizumab were administered. However, no clinical benefit was noted, and the patient died 3 months postoperatively. CONCLUSION: This is the first report of a case of SMARCB1-negative rhabdoid colon carcinoma with high MSI treated with pembrolizumab. Rhabdoid carcinoma is highly aggressive; therefore, additional studies are required to determine the therapeutic strategy for SMARCB1-negative rhabdoid colorectal carcinoma.

Reevaluation of regional lymph nodes in patients with pancreatic ductal adenocarcinoma in the pancreatic body and tail.

Introduction: In patients with pancreatic ductal adenocarcinoma (PDAC) in the pancreatic body (Pb) and tail (Pt), the appropriate area for lymphadenectomy is controversial. This study aimed to reevaluate the extent of lymph node (LN) metastasis in Pb- and Pt-PDAC, and to define the optimal area of LN dissection. Patients and methods: This single-center retrospective study evaluated patients with Pb- and Pt-PDAC who underwent distal pancreatectomy with extended lymphadenectomy between 2006 and 2020. LN metastasis in >3.0% of patients were defined as new regional LN. Results: The study cohort included 135 patients with Pb-PDAC and 42 patients with Pt-PDAC. In patients with Pb-PDAC, LNs around the splenic artery (SPA) had the highest metastasis-positive rate (54.1%). LNs along the left gastric artery, common hepatic artery, celiac axis (CA), superior mesenteric artery (SMA), and splenic hilus were defined as new regional LNs. In patients with Pt-PDAC, LNs at the splenic hilum had the highest metastasis-positive rate (38.1%). The station and LN around the SPA were defined as new regional LNs in those with Pt-PDAC. Metastasis beyond the newly defined regional LNs was not associated with survival. The incidence of LN metastasis was lower in patients who received preoperative chemotherapy than in those who underwent upfront surgery in both Pb- and Pt-PDAC. Conclusion: Although it needs to be verified in future multicenter studies, LN of both the CA and SMA systems should be dissected in patients with Pb-PDAC. However, only those around the SPA and splenic hilus should be dissected routinely in those with Pt-PDAC.

Ensitrelvir is effective against SARS-CoV-2 3CL protease mutants circulating globally.

The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been a public health concern worldwide. Ensitrelvir (S-217622) has been evaluated as an antiviral treatment for COVID-19, targeting SARS-CoV-2 3C-like protease (3CLpro). Ensitrelvir has been reported to have comparable antiviral activity against some of the SARS-CoV-2 variants: alpha, beta, gamma, delta, and omicron (BA.1.18). In this paper, we describe that ensitrelvir is effective against newly emerging SARS-CoV-2 variants and globally prevalent 3CLpro mutations. Ensitrelvir exhibited comparable antiviral activity against SARS-CoV-2 variants, including recently emerging ones: omicron (BA1.1, BA.2, BA.2.75, BA.4, BA.5, BQ.1.1, XBB.1, and XE), mu, lambda, and theta. Genetic surveillance of SARS-CoV-2 3CLpro, the target of ensitrelvir, was conducted using a public database and identified 11 major 3CLpro mutations circulating globally (G15S, T21I, T24I, K88R, L89F, K90R, P108S, P132H, A193V, H246Y, and A255V). The 3CLpro mutation from proline to histidine at amino acid position 132 was especially identified in the omicron variant, with prevalence of 99.69%. Enzyme kinetic assay revealed that these 3CLpro mutants have enzymatic activity comparable to that of the wild type (WT). Next, we assessed the inhibitory effect of ensitrelvir against mutated 3CLpro, with it showing inhibitory effects similar to that against the WT. These in vitro data suggest that ensitrelvir will be effective against currently circulating SARS-CoV-2 variants, including omicron variants and those carrying 3CLpro mutations, which emerging novel SARS-CoV-2 variants could carry.

Survival impact of occult liver metastasis and peritoneal dissemination compared with radiologically defined distant organ metastasis in pancreatic ductal adenocarcinoma.

BACKGROUND: Characteristics and prognoses of patients with occult metastases (OM) of pancreatic ductal adenocarcinoma (PDAC) compared with radiologically defined metastases (RM) have been rarely reported. OBJECTIVE: We aimed to clarify the prognosis of OM compared with RM and to establish a treatment strategy for PDAC patients with OM. METHODS: This single-institution, retrospective study evaluated patients with unresectable PDAC between 2008 and 2018. OM was defined as abdominal metastasis that was detected by staging laparoscopy or open laparotomy but not in the initial assessment of radiological images. RESULTS: OM and RM were identified in 135 and 112 patients, respectively. Eastern Cooperative Oncology Group Performance Status (ECOG PS), neutrophil to lymphocyte ratio (NLR), tumor diameter, and rate of local unresectability were significantly lower in the OM group. Median overall survival (OS) of OM was significantly better than that of RM (13.0 vs 8.9 months, p < 0.001). In multivariate analysis of OS, ECOG PS ≥ 1 (HR 1.64, p = 0.009), NLR ≥5 (HR 1.97, p = 0.004), carbohydrate antigen (CA) 19-9 ≥1000 (HR 1.68, p = 0.001), tumor diameter ≥40 mm (HR 1.40, p = 0.027), conversion surgery (HR 0.12, p < 0.001), and multiple lines of chemotherapy (HR 0.38, p < 0.001) were independent predictors. However, type of metastasis (OM vs RM) not an independent predictor (HR 1.10, p = 0.590). CONCLUSION: The prognosis of PDAC with OM was relatively better than that with RM, but general and nutritional statuses, primary tumor size and CA19-9, conversion surgery and multiple lines of chemotherapy were independent predictors but not tumor burden.

Computed tomography revealed the correlation between radiolucency and alignment of all-polyethylene pegged glenoid component more than 10 years after total shoulder arthroplasty in the Japanese population.

BACKGROUND: Anatomical total shoulder arthroplasty (TSA) provides successful long-term outcomes but complications can occur after 10 years that require revision. Computed tomography (CT) is a useful tool for assessing radiolucent lines around the glenoid component of TSA; however, the merits of long-term post-TSA follow up with CT are unclear. The purpose of this study was to evaluate the long-term outcomes after TSA of Japanese population and to identify factors related to radiolucency around the glenoid component using CT. METHODS: A retrospective review was conducted of TSA patients who had completed at least 10 years of clinical follow up. Radiographs and CT images of the affected shoulder obtained at the last follow up were evaluated for radiolucent lines around the stem and each peg, superior inclination and retroversion of the glenoid component, subluxation index, and critical shoulder angle (CSA). Shoulder ROM, Constant-Murley score and UCLA score were compared between the preoperative and last follow up period. RESULTS: Eighteen shoulders in 16 patients met the inclusion criteria. Mean patient age was 61 years, mean follow up period was 137 months, and mean Yian CT score was 19%. CT score was significantly highest in pegs located inferiorly (p < 0.05). Mean glenoid superior inclination was 12.6°, retroversion was -0.3°, subluxation index was 46%, and CSA was 33.7°. Glenoid superior inclination was significantly lower (p = 0.007) in shoulders with possible loosening than in cases with no loosening (5.0° vs 15.6°). Mean Constant score and UCLA score improved significantly after TSA, from 25.8 to 10.7 points preoperatively to 70.1 and 28.9 points postoperatively, respectively. Mean shoulder flexion, internal rotation, and external rotation also showed improvement postoperatively. CONCLUSION: TSA provides good long-term outcomes. Radiolucency was present most frequently around the inferior pegs of the glenoid component. Glenoid superior inclination may affect the formation of radiolucent lines around glenoid pegs. LEVEL OF EVIDENCE: Level IV; Case Series; Treatment study.

[A Case of Recurrent Gastric Cancer with Long-Term Control via Two Resections and Multidisciplinary Treatment Including Nivolumab].

A 78-year-old woman underwent total gastrectomy with distal pancreatectomy and splenectomy for type 3 gastric cancer and a cystic tumor of the pancreas. Her pathological diagnosis was pT4aN3bM0, pStage ⅢC, and HER2-negative. Capecitabine and oxaliplatin was started as an adjuvant therapy, and capecitabine was administered until 1 year postoperatively. Thirteen months after surgery, she had a recurrence in S3 of the liver and underwent liver resection due to solitary metastasis. The postoperative diagnosis was peritoneal dissemination of gastric cancer with invasion of the falciform ligament. S-1 was started postoperatively. Ten months after surgery, she had a recurrence in S3 of the liver and underwent repeated resection. It invaded into the diaphragm and pericardium, and the final diagnosis was recurrent peritoneal dissemination of gastric cancer. After 5 courses of paclitaxel and ramucirumab, nivolumab was started as a fourth-line therapy for the recurrence of the right supraclavicular lymph nodes, bone, and liver. She had some immune-related adverse events(irAE), including hypothyroidism and hypoadrenocorticism, which required management, but she maintained PR more than 2 years after the initiation of the treatment. Multimodality therapies, including repeated resection and nivolumab, were considered to help her long-term survival.

[A Case of Pancreatic Metastasis from Renal Cell Carcinoma 16 Years after Left Nephrectomy].

A 73-year-old woman underwent left nephrectomy for renal cell carcinoma(RCC). The computed tomography(CT)and magnetic resonance imaging(MRI)revealed a 20-mm tumor in the pancreatic tale showing early enhancement in the arterial phase 16 years after surgery. Fluorodeoxyglucose positron emission tomography(FDG-PET)showed slightly uptake (maximum standard uptake value: SUVmax 2.3)and EUS-FNA showed a hyper-vascularized tumor in the pancreatic tail. A single pancreatic metastasis from RCC was diagnosed, and we performed distal pancreatectomy. The histopathological diagnosis was a metastatic pancreatic tumor from RCC. The postoperative course was uneventful and 1 month after surgery, she is alive with no recurrence.

Oncological role of surgical resection in patients with pancreatic ductal adenocarcinoma with liver-only synchronous metastases in a single-center retrospective study.

Background: Surgical resection for liver-only synchronous metastases of pancreatic ductal adenocarcinoma remains controversial. We investigated the role of conversion surgery in patients with a favorable response to systemic chemotherapy. Methods: Patients (n=49) were diagnosed liver-only synchronous metastases using staging laparoscopy or open laparotomy between 2007 and 2022. Clinical outcomes were retrospectively compared among patients who underwent conversion surgery (n=10), upfront surgery with or without short-term neoadjuvant chemotherapy (UpS/short NAC) for oligometastases and occult metastases limited to the liver (n=8), and chemotherapy only for resectable or borderline resectable disease with occult liver-only metastases (n=31). The surgical indication of conversion surgery was fixed as the ABC criteria, namely, Anatomical objective response of disappearance of liver metastases on imaging studies, Biological response of CA19-9 level decrease to ≤150 U/mL, and Conditional response of surgical fitness. In addition to the above ABC criteria, tumor disappearance at the liver was repeatedly confirmed using staging laparoscopy (laparoscopic response; L), and metabolic complete responses were confirmed using positron emission tomography-computed tomography (CT) (metabolic response; M). Results: Median survival time from initial treatment was 9.9 months [95% confidence interval (CI): 8.3-10.9] in the chemotherapy group, 10.4 months (95% CI: 6.6-17.8) in the UpS/short NAC group, and 36.7 months (95% CI: 19.0-84.8) in the conversion surgery group (conversion surgery vs. UpS/short NAC, P=0.002; conversion surgery vs. chemotherapy, P<0.001; UpS/short NAC vs. chemotherapy, P=0.554). One patient in the UpS/short NAC group and three in the conversion surgery group achieved 5-year survival. Among them, two patients with initially multiple liver metastases (≥10) in the conversion surgery group survived beyond 5 years. Only conversion surgery was a significant independent prognostic factor in a total cohort (hazard ratio; 0.173, P=0.002). Conclusions: Conversion surgery, but not UpS/short NAC, may enhance survival in patients with synchronous liver metastases and favorably anatomical, biological and conditional responses to systemic chemotherapy.

[A Case of Radical Resection after Neoadjuvant Chemotherapy for Rectal Cancer with Pelvic Abscess].

A 66-year-old man with a history of frequent diarrhea was diagnosed with rectal cancer with obstruction and a pelvic abscess. Following a transverse colostomy, he was referred to our hospital. The initial diagnosis was rectal cancer(cT4a N1bM0, cStage Ⅲb)and a pelvic abscess due to tumor perforation. To address this condition, we performed neoadjuvant chemotherapy using a combination of 5-fluorouracil, Leucovorin, oxaliplatin, and irinotecan(FOLFOXIRI). Following 6 courses of FOLFOXIRI, the abscess disappeared and no signs of tumor progression and distant metastases were detected. Subsequently, we performed radical resection with D3LD2 lymph node dissection, leading to a pathological diagnosis of ypT3N1aM0, ypStage Ⅲb. The patient then underwent adjuvant chemotherapy with capecitabine and oxaliplatin(CAPOX). No recurrence was observed after 9 months of follow-up.

Implications of navigation system use for glenoid component placement in reverse shoulder arthroplasty.

Recently, three-dimensional (3D) planning, patient-specific instruments, and navigation system have been developed to improve the accuracy of baseplate placement in reverse shoulder arthroplasty (RSA). The purpose of this study was to evaluate baseplate placement using the navigation system. Sixty-four shoulders in 63 patients who underwent RSA for rotator cuff tear arthropathy or irreparable rotator cuff tears were enrolled. Conventional RSA was performed in 31 shoulders and navigated RSA using pre-operative planning software was performed in 33 shoulders. The use of augmented baseplates, the version and inclination of the baseplate, and screw length were compared between conventional RSA and navigated RSA. Augmented baseplates were used more frequently in navigated RSA than in conventional RSA (20 vs 9 shoulders, p = 0.014). Baseplate alignment was 1.0° (SD 5.1) of retroversion and 2.4° (SD 6.8) of superior inclination in conventional RSA and 0.2° (SD 1.9) of anteversion and 0.3° (SD 1.7) of superior inclination in navigated RSA. Compared with conventional RSA, precision of baseplate version and inclination were higher in navigated RSA (both p < 0.001). Superior, inferior, and posteroinferior screws were significantly longer in navigated RSA than in conventional RSA (p = 0.021, 0.001 and < 0.001, respectively). Precision of superior and inferior screw lengths was significantly higher in navigated RSA than in conventional RSA (both p = 0.001). Our results suggest that adoption of pre-operative planning software increased augmented baseplate use to minimize the glenoid reaming. The navigation system allows placement of the baseplate accurately, according to the pre-operative plan. Furthermore, the navigation system enables monitoring of screw length and direction in real time.