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Background: Colonic varices are a rare gastrointestinal anomaly often associated with portal hypertension. Arteriovenous fistula (AVF) in the inferior mesenteric artery (IMA) region is even rarer. Diagnosis and treatment of these entities present unique challenges, especially when the IMA is involved., Case Presentation: A 48-year-old man with a history of cholecystectomy presented with after a positive fecal occult blood test. Investigations revealed varices from the splenic flexure to the transverse colon and suspected AVF in the IMA region. Given the high risk and low efficacy of endoscopic and radiological interventions, laparoscopic sigmoidectomy was performed. This surgical approach successfully addressed both the AVF and the associated varices., Conclusion: This case underscores the importance of surgical intervention for AVF and colonic varices in the IMA region, particularly when other treatment options pose high risks and have limited efficacy. The favorable postoperative outcome in this case highlights the effectiveness of carefully chosen surgical methods when managing such complex and rare conditions., (© 2024. The Author(s).)

Objectives: Deep pelvic abscesses are surrounded by the pelvic bones, bladder, gynecological organs, intestinal tract, and nerve and vascular systems, and are approached by various routes for drainage. The transgluteal approach is often performed under computed tomography guidance; however, if ultrasonography can be used to confirm the approach, it is considered more effective because it reduces radiation exposure and allows for real-time puncture under sonographic and fluoroscopic guidance., Methods: This retrospective study was conducted at Tobata Kyoritsu Hospital (Fukuoka, Japan) between April 1, 2021, and December 31, 2022. Sonographically guided transgluteal drainage with fluoroscopy was performed in five consecutive cases of deep pelvic abscesses using a 3D image analysis system (SYNAPSE VINCENT) to study the anatomy for safe puncture., Results: Three patients had postoperative abscesses from colorectal cancer, one caused by perforation of the appendicitis, and one caused by sigmoid diverticulitis. The average drainage duration was 11 days (SD = 6.7). No complications, such as bleeding or nerve damage, were observed., Conclusions: We constructed a 3D image of the puncture route of the trans greater sciatic foramen using SYNAPSE VINCENT to objectively comprehend the anatomy and puncture route. The ideal transgluteal approach is to insert the catheter as close to the sacrum as possible at the level of the infrapiriformis. The parasacrum infrapiriformis approach can be performed safely and easily using ultrasound guidance and fluoroscopy., Competing Interests: Conflicts of Interest There are no conflicts of interest., (Copyright © 2024 The Japan Society of Coloproctology.)

Background: We aimed to retrospectively compare the clinical outcomes of endoscopy-assisted first-rib resection for thoracic outlet syndrome (TOS) between overhead athletes and nonathletes and investigate the return to same-level sports rate in overhead athletes., Methods: We retrospectively reviewed 181 cases with TOS (75 women, 106 men; mean age, 28.4 years; range, 12-57 years) who underwent endoscopy-assisted first-rib resection. We divided into two groups: 79 overhead athletes and 102 nonathletes groups. A transaxillary approach for first-rib resection and neurovascular decompression was performed under magnified visualization. Endoscopic findings related to the neurovascular bundle, interscalene distance, and scalene muscle were evaluated intraoperatively. We assessed the Roos and Disability of the Arm, Shoulder, and Hand scores, return to same-level sports rate, and ball velocity., Results: Overhead athletes were significantly more likely to be men, younger, used the dominant side more frequently, and have a larger physique, more shoulder and elbow pain, and shorter symptom duration. The outcomes of the Roos score revealed significant differences in excellent or good results between overhead athletes (91.1%) and nonathletes (62.8%). The two groups significantly differed in preoperative and postoperative Disability of the Arm, Shoulder, and Hand and recovery rate scores ( P  = .007, < .001, < .001)., Conclusion: Overhead athletes with TOS were more likely to be men, younger, dominant side more frequently, and have more shoulder and elbow pain, and a shorter symptom duration. Endoscopy-assisted transaxillary first-rib resection and neurolysis provided superior clinical outcomes in overhead athletes with TOS compared with nonathletes and a high return-to-same-level-play rate in sports., (© 2024 The Authors.)

A 64-year-old male was referred to our hospital with both advanced rectal cancer and lung tumor with swollen lymph nodes in the lung hilum. The patient underwent laparoscopic low anterior resection followed by systematic lobectomy of the lung 2 months later. Postoperative pathological examination revealed a diagnosis of metastatic lung tumor and metastasis in the lung hilum. However, hilar lymph node metastasis is considered a poor prognostic factor for lung metastasis. Herein, we report a case of synchronous lung metastasis and hilar lymph node metastasis from colorectal cancer that achieved 20 months of recurrence free survival with surgical therapy alone.

Background: Massive rotator cuff tears (RCTs) are complicated by muscle atrophy, fibrosis, and intramuscular fatty degeneration, which are associated with postoperative tendon-to-bone healing failure and poor clinical outcomes. We evaluated muscle and enthesis changes in large tears with or without suprascapular nerve (SN) injury in a rat model., Methods: Sixty-two adult Sprague-Dawley rats were divided into SN injury (+) and SN injury (-) groups (n=31 each), comprising tendon (supraspinatus [SSP]/infraspinatus [ISP]) and nerve resection and tendon resection only cases, respectively. Muscle weight measurement, histological evaluation, and biomechanical testing were performed 4, 8, and 12 weeks postoperatively. Ultrastructural analysis with block face imaging was performed 8 weeks postoperatively., Results: SSP/ISP muscles in the SN injury (+) group appeared atrophic, with increased fatty tissue and decreased muscle weight, compared to those in the control and SN injury (-) groups. Immunoreactivity was only positive in the SN injury (+) group. Myofibril arrangement irregularity and mitochondrial swelling severity, along with number of fatty cells, were higher in the SN injury (+) group than in the SN injury (-) group. The bone-tendon junction enthesis was firm in the SN injury (-) group; this was atrophic and thinner in the SN injury (+) group, with decreased cell density and immature fibrocartilage. Mechanically, the tendon-bone insertion was significantly weaker in the SN injury (+) group than in the control and SN injury (+) groups., Conclusions: In clinical settings, SN injury may cause severe fatty changes and inhibition of postoperative tendon healing in large RCTs. Level of evidence: Basic research, controlled laboratory study.

Background: The term shoulder instability refers to a variety of mechanisms and clinical presentations. One of the common pathologies of throwing disorders is internal impingement with anterior instability. Most throwing athletes with symptomatic internal impingement with anterior instability exhibit positive apprehension and relocation test results, whereas those with recurrent anterior shoulder instability display positive apprehension test results. While the glenoid labrum-inferior glenohumeral ligament complex is a significant critical stabilizer for the prevention of anterior shoulder dislocation, the characteristics of the essential lesion in internal impingement with anterior instability have not been determined yet. This study aimed to compare the intra-articular lesion of athletes with internal impingement related to the overhead throwing motion in athletes with a traumatic shoulder dislocation., Methods: Sixty-one athletes (all men; mean age, 25.2 ± 12.6 yr) who underwent an arthroscopic procedure were divided into 2 groups: 25 in the throwing group and 36 in the dislocation group. All shoulders had subtle glenohumeral instability defined by a positive anterior apprehension test and a relocation test. Those with voluntary and multidirectional instability and large glenoid bone loss (more than 25%) were excluded from the current study. All shoulders were evaluated for the following evidence: rotator cuff injury, superior labrum tear anterior and posterior lesions, labral pathologies including Bankart lesions, osteochondral lesions to the humeral head, biceps tendon fraying or rupture, and inferior glenohumeral ligament and middle glenohumeral ligament (MGHL) conditions., Results: Arthroscopic findings of the throwing group showed more supraspinatus injuries (92% and 25%, P < .001), type II superior labrum tear anterior and posterior lesions (60% and 3%, P < .001), posterosuperior labral lesions (92% and 39%, P < .001), and hypoplastic MGHLs (56% and 6%, P < .001) and lesser Bankart lesions (8% and 92%, P < .05) than those of the dislocation group., Conclusions: These results indicate that the characteristic lesions of internal impingement with anterior instability in throwing athletes include partial thickness rotator cuff tears, superior labrum tear anterior and posterior lesions, posterosuperior labral tears, and hypoplastic MGHLs. As expected, the physiopathology of internal impingement with anterior instability in throwing athletes may be related to the dysfunction of the anterosuperior glenohumeral capsular ligament, including the MGHL, rather than the inferior glenohumeral ligament as in traumatic anterior shoulder dislocations. These findings would be useful for defining treatment strategies for internal impingement with anterior instability in overhead throwing athletes., (Copyright © 2022 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.)

Background/aim: Malignant biliary obstruction (MBO) is a life-threatening condition. We aimed to investigate the outcome of salvage percutaneous transhepatic biliary drainage (PTBD) in patients with unresectable MBO due to failure of management by endoscopic retrograde cholangiopancreatography (ERCP) and/or prior surgical bypass., Patients and Methods: Fifty-two consecutive patients (mean age, 69 years; 44.2% women) underwent salvage PTBD between 2013 and 2020., Results: The median overall survival rate was 4.2 months, with a 95% confidence interval (CI) of 1.9-5.7. The median overall survival (OS) were 11.1 months and 1.9 months for patients who underwent chemotherapy (n=17) and best supportive care (n=35), respectively (p=0.0005). Independent factors predicting poor outcome were best supportive care, with a hazard ratio (HR) of 3.3 (95%CI=1.3-8.5), American Society of Anesthesiologists physical status classification (ASA) with a HR of 13.5 (95%CI=1.3-136.0) and Eastern Cooperative Oncology Group (ECOG) performance status of 4, with a HR of 3.3 (95%CI=1.0-6.2)., Conclusion: Salvage PTBD with chemotherapy has the potential to achieve prolonged survival in patients with unresectable MBO, including those with failure of ERCP and/or surgical bypass., (Copyright © 2022 International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

Background and study aims  The efficacy of endoclips for colonic diverticular hemorrhage remains unclear. The aim of the current study was to evaluate the safety and efficacy of endoclips versus endoscopic band ligation (EBL) for the treatment of colonic diverticular hemorrhage. Patients and methods  At Nara City Hospital, 93 patients with colonic diverticular hemorrhage with stigmata of recent hemorrhage (SRH) were treated using endoclips or EBL between January 2013 and December 2018. We classified the patients treated by endoclips into the direct clipping group and indirect clipping group. Endoclips were placed directly onto the vessel if technically feasible (direct clipping). When direct placement of endoclips onto the vessel was not possible, the diverticulum was closed in a zipper fashion (indirect clipping). Patient demographics, rate of early rebleeding within 30 days after initial treatment, and complications were retrospectively evaluated. Results  Of the 93 patients, 34, 28, and 31 were in the direct clipping group, indirect clipping group, and EBL group, respectively. Rates of early rebleeding in the direct clipping, indirect clipping, and EBL groups were 5.9 % (2/34), 35.7 % (10/28), and 6.5 % (2/31), respectively ( P  = 0.006: direct clipping vs indirect clipping, P  = 1: direct clipping vs EBL). No complications occurred in any groups. All patients who had early rebleeding in the direct clipping group underwent EBL, and no further bleeding occurred after repeat therapy. Conclusions  Direct clip placement is acceptable as the first treatment choice for colonic diverticular hemorrhage. When direct placement of endoclips is not possible, EBL should be performed instead of indirect clipping., Competing Interests: Competing interests None

Purpose: To compare arthroscopic suture bridge (SB) techniques with medial tying to those without tying, considering clinical and structural outcomes., Methods: We included 124 patients with rotator cuff tears after arthroscopic rotator cuff repair (ARCR). Fifty-three patients with clinical and structural evaluations 3, 12, and 24 months postoperatively were included and divided into 29 patients with medial tying (WMT group) and 24 without tying (WOMT group). Clinical outcomes comprised the University of California Los Angeles (UCLA) and Japanese Orthopaedic Association (JOA) scores. Structural outcomes were evaluated with magnetic resonance images (MRI) using Sugaya classifications., Results: JOA and UCLA scores in the WMT and WOMT groups improved significantly from before surgery to 24 months after surgery (P < 0.01, respectively). No significant difference was noted between groups. No significant postoperative retears (Sugaya types 4 and 5) between WMT and WOMT groups were noted at 3 months (5 vs 3 cases), 12 months (6 vs 5 cases), and 24 months (7 vs 6 cases) postoperatively. Complete healing (Sugaya type 1) was noted at 3 months (8 vs 11 cases), 12 months (10 vs 10 cases), and 24 months (8 vs 13 cases, P = 0.024) postoperatively. Incomplete healing (Sugaya types 2 and 3) were noted at 3 months (16 vs 10 cases), 12 months (13 vs 9 cases), and 24 months (14 vs 5 cases, P = 0.024) postoperatively., Conclusion: Clinical outcomes for both techniques were comparable, but the number of incompletely healed tendons in SB with medial tying was significantly larger at 24 months after surgery., Level of Evidence: This study is a level III, case-control study., Clinical Relevance: This study revealed the influence of medial tying in rotator cuff repair.

Background: It is known that complex regional pain syndrome (CRPS) occurs after arthroscopic rotator cuff repair (ARCR); however, few studies have investigated this complication. Therefore, the purpose of the present study was to evaluate CRPS after ARCR., Methods: A total of 182 patients who underwent ARCR were enrolled in this study. The average age of patients was 62.8 ± 10.0 years, with an average follow-up period of 21.5 ± 38.1 months. CRPS criteria outlined by the Ministry of Health, Labor, and Welfare study team for CRPS in Japan (MHLWJ) and International Association for the Study of Pain (IASP 2005) were utilized for diagnosis. There are two rating systems for the "clinical purpose" and "research purpose" in both criteria, respectively. Clinical outcomes, including Japanese Orthopedic Association (JOA) and University of California, Los Angeles scores, were evaluated using univariate and multivariate analysis., Results: CRPS exclusively occurred in the hand of the operated limb, developing within 3 months of surgery. Two or more of the following symptoms were noted in patients with the hand lesion associated with CRPS: edema (93.4%), restricted range of motion (83.4%), hyperalgesia (30.1%), paridrosis (20.4%), and atrophic change (12.2%). Under these conditions, the incidences of CRPS were 24.2% (44/182) when evaluated by the MHLWJ rating system for the "clinical purpose;" 11% (22/182) by the MHLWJ rating system for the "research purpose;" 6% (11/182) by the IASP 2005 for the "clinical purpose;" and 0.5% (1/182) by the IASP 2005 for the "research purpose." Results of multivariate analysis demonstrated that "Function" in the JOA score was a risk factor for the development of CRPS after ARCR, when evaluated by a system for the "clinical purpose" of the MHLWJ., Conclusion: Following ARCR, CRPS-induced hand lesions occur more frequently than is generally believed, thereby suggesting that its impact on surgical outcomes should be clarified in the future., (Copyright © 2017 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.)

Background: Previous studies have evaluated the risk factors for retear of large/massive rotator cuff tears (RCTs) that were treated arthroscopically; however, most studies did not evaluate tear patterns. The present study hypothesized that postoperative risk factors are affected by the tearing patterns in large/massive cuff tears in patients undergoing arthroscopic rotator cuff repair (ARCR)., Methods: One hundred fifty patients with large/massive cuff tears underwent ARCR at our institution. Of these, 102 patients were enrolled in this study, with an average symptom duration of 36.3 ± 43.9 months and average age of 63.9 ± 9.4 years. According to the arthroscopic findings and magnetic resonance imaging (MRI), the 102 patients were divided into three groups based on the tendon location: anterosuperior tears (N = 59, group AS), posteosuperior tears (N = 21, group PS), and anteroposterior-extending tears (N = 22, group APE). Functional outcome was evaluated preoperatively and postoperatively using the Japanese Orthopedic Association (JOA) score and the University of California, Los Angeles (UCLA) score. Retear was evaluated with MRI at a minimum of 1 year after surgery, using Sugaya's classification; Types IV and V were considered postoperative retears. Factors affecting postoperative retear were examined with univariate and multivariate analyses., Results: JOA/UCLA scores significantly improved postoperatively in the three groups (P < 0.01 for all). Postoperative retear was noted in 26 of 102 patients (25.5%) in this series: 10 patients in group AS (16.9%), 9 in group PS (42.9%), and 7 in group APE (31.8%). The retear rate was significantly higher in group PS than in the other two groups (P = 0.02). Multivariate analysis showed that decreased preoperative active external rotation range was a unique risk factor for postoperative retear in the PS and APE groups (95% confidence interval: 0.02-0.18, cut-off value: 25°, with an area under the curve of 0.90, P = 0.0025)., Conclusions: Although multivariate analysis failed to detect significant risk factor for retear in patients with anterosuperior large/massive cuff tears who undergo ARCR, it demonstrated that active external rotation less than 25° before surgery is a significant risk factor in those with posterosuperior large/massive tears. This study may help surgeons understand the results of arthroscopic surgery in patients with large/massive tears.

Successful rotator cuff repair requires biological anchoring of the repaired tendon to the bone. However, the histological structure of the repaired tendon-bone interface differs from that of a normal tendon insertion. We analysed differences between the normal tendon insertion and the repaired tendon-bone interface after surgery in the mechanical properties, histomorphometric analysis, and 3-dimensional ultrastructure of the cells using a rat rotator cuff repair model. Twenty-four adult Sprague-Dawley (SD) rats underwent complete cuff tear and subsequent repair of the supraspinatus tendon. The repaired tendon-bone interface was evaluated at 4, 8, and 12 weeks after surgery. At each time point, shoulders underwent micro-computed tomography scanning and biomechanical testing (N = 6), conventional histology and histomorphometric analysis (N = 6), and ultrastructural analysis with focused ion beam/scanning electron microscope (FIB/SEM) tomography (N = 4). We demonstrated that the cellular distribution between the repaired tendon and bone at 12 weeks after surgery bore similarities to the normal tendon insertion. However, the ultrastructure of the cells at any time point had a different morphology than those of the normal tendon insertion. These morphological differences affect the healing process, partly contributing to re-tearing at the repair site. These results may facilitate future studies of the regeneration of a normal tendon insertion.

Purpose: (1) To compare clinical outcomes between patients with large or massive rotator cuff tears who have healed cuffs and patients with postoperative structural failure (retear after complete or partial repair) and (2) to identify factors associated with clinical outcomes in patients with postoperative structural failure., Methods: We conducted a retrospective study of consecutive patients with large or massive cuff tears who underwent arthroscopic repair at our institution between 2005 and 2012. On the basis of intraoperative findings and magnetic resonance imaging at final follow-up, the patients were divided into 3 groups: healed group, retear group (after complete repair), and partial-repair group. The outcome measures comprised the Japanese Orthopaedic Association (JOA) and University of California, Los Angeles (UCLA) scores; muscle strength; and range of motion. The tear length, tear width, muscle atrophy, and fatty degeneration were evaluated by preoperative and postoperative magnetic resonance imaging. The extent of tendon reattachment to the superior, middle, and inferior facets and the lesser tuberosity was examined on magnetic resonance images at final follow-up., Results: In total, 74 patients (healed, 41; retear, 19; and partial repair, 14) were included in this study. The mean age was 63.8 ± 8.5 years, with a mean follow-up period of 3.6 ± 1.4 years. The postoperative JOA and UCLA scores significantly improved in all 3 groups, but the differences were not significant. In the retear and partial-repair groups, postoperative tendon preservation at the middle facet significantly affected the JOA and UCLA scores (P = .003 and P = .014, respectively)., Conclusions: The JOA and UCLA scores were significantly improved in patients with structural failure. Under these conditions, the only clinical factor that affected patient outcome was tendon healing at the middle facet. Thus tendon preservation at the middle facet was a predictor of good clinical outcomes in patients who underwent arthroscopic rotator cuff repair of large or massive tears and had postoperative structural failure., Level of Evidence: Level III, case-control study., (Copyright © 2016 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)

Corticosteroids (CS) or hyaluronic acid (HA) is used in subacromial injection for the conservative treatment of rotator cuff tears (RCT); this study addresses the question of how CS and HA affect the tendon tissue and fibroblasts in vitro and in rats. Cell proliferation assays were performed in human tendon fibroblasts from RCT. Rats underwent surgery to create RCT, and the surgical sites were injected with CS or HA. The rotator cuff tendons were subjected to biomechanical testing, microscopic and immunohistochemical analysis of proliferating cell nuclear antigen (PCNA), and ultrastructural analysis. Cell proliferation was significantly decreased with CS in vitro (p < 0.05). Maximal load of CS-treated tendons was significantly decreased compared with that of HA-treated tendons (p < 0.05), as well as PCNA(+) cells at 2 weeks (p < 0.05). Ultrastructural observations of the CS-treated rats detected apoptosis of tendon fibroblasts 24 h after surgery. Histological and biomechanical data 4 weeks after surgery were not significant among the three groups. Unlike HA, CS caused cell death, and inhibition of the proliferation of tendon fibroblasts, leading to a delay of tendon healing involved and a subsequent decrease of biomechanical strength at the surgical site., (© 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.)

Aim: No pharmacological therapies have been established for non-alcoholic steatohepatitis (NASH), which can lead to liver-related mortality. Human placental extract (HPE), which has anti-inflammatory effects, has been expected to be a promising treatment for chronic liver disease. This pilot study was conducted to evaluate the efficacy of HPE for biopsy-diagnosed NASH., Methods: After a lifestyle intervention for 12 weeks, 10 subjects with abnormal alanine aminotransferase (≥30 IU/L) and biopsy-proven NASH (Non-Alcoholic Fatty Liver Disease Activity Score [NAS], ≥4) received i.m. injections of HPE (Laennec) at a dose of 4 mL/day twice per week for 24 weeks, and seven of them underwent a second liver biopsy after the treatment. Liver biopsies were scored for NAS and fibrosis. Histological response was defined as a decrease of 2 points or more in NAS and no increase in fibrosis., Results: Serum transaminase activities were significantly lower at 8 weeks compared with pretreatment levels in nine patients who continued treatment for 24 weeks. One patient refused to continue the treatment soon after starting therapies. In seven patients undergoing post-treatment biopsies, NAS (mean [standard deviation]) mildly decreased from 5.29 (0.95) to 4.00 (1.83) without reaching statistical significance (P = 0.078). Histological response was observed in all three obese patients and in only one of four non-obese ones. No significant changes were observed in body mass index, lipid profiles and diabetic control/insulin resistance., Conclusion: In NASH patients who received HPE treatment, significant reductions in serum liver enzymes were obtained after 8 weeks. Histological efficacy may be better in obese patients than in non-obese ones., (© 2014 The Japan Society of Hepatology.)

Background: Clinical data regarding Helicobacter pylori (H. pylori) infection in nonalcoholic fatty liver disease (NAFLD) are limited. The aim was to evaluate H. pylori infection in patients with NAFLD and its association with disease severity., Methods: One hundred and thirty patients with biopsy-proven NAFLD [43 with nonalcoholic fatty liver (NAFL) and 87 with nonalcoholic steatohepatitis (NASH)] were recruited for blood samples for anti-H. pylori immunoglobulin G (IgG) and standard biochemical tests were obtained after overnight fasting. Glucose tolerance was evaluated by 75-g oral glucose tolerance test. Liver biopsies were scored for NAFLD activity score (NAS), fibrosis and iron deposits., Results: H. pylori IgG seropositivity was found in 40 % of patients overall. The prevalence of NASH was significantly higher in the patients with H. pylori IgG seropositivity (81 %) than in those without (58 %, p = 0.008). Glucose intolerance was similar between the two groups. The total NAS and the grade of hepatocyte ballooning were higher in the patients with H. pylori IgG seropositivity than in those without, while the hepatic iron grade was lower in the patients with H. pylori IgG seropositivity than in those without. H. pylori infection (p = 0.030), female gender (p = 0.029), and NAFIC score ≥ 2 points (p < 0.001) could independently predict NASH in logistic regression analysis, independent of age, obesity and glucose tolerance., Conclusion: The association of H. pylori seropositivity with hepatocyte ballooning suggests that H. pylori infection may represent another contributing factor in the progression from NAFL to NASH. Eradicating H. pylori infection may have therapeutic prospects in NASH treatment.

Studies have demonstrated favorable outcomes of arthroscopic decompression for ganglion cyst in the supraspinous fossa; however, little attention has been paid to the difficulty in detecting these cysts during arthroscopy. In this report, we present 2 cases in which ganglion cysts in the supraspinous fossa were undetectable during arthroscopy. The ganglion cysts were not identified in these cases during surgery despite arthroscopic decompression being performed through the area in which the cyst was expected until the suprascapular nerve was entirely exposed. After surgery, magnetic resonance imaging (MRI) confirmed the disappearance of the ganglion cyst and external rotation strength was fully improved, without shoulder pain. We emphasize here that surgeons should be aware of this difficulty when performing arthroscopic decompression of ganglion cysts in the supraspinous fossa.

The influence of contraction stress in composite resins on both the shear bond strength to dentin (BS) and marginal adaptation in a standardized dentin cavity was investigated using three restorative resin systems. A teflon ring mold (TF) or copper ring with a roughened inner surface (CP) placed on human tooth dentin was filled with the composite resin, and a shearing test was then performed. ANOVA of BS demonstrated a significant influence from the resin systems and type of molds. BSCP tended to be lower than BSTF in all three systems. This suggested that the inner surface of the CP restricted the flow of resin and then contraction stress occurred at the interface of the bond to the dentin. The system which demonstrated the smallest difference between BSTF and BSCP also showed the best adaptation. This result indicates that contraction stress in the composite resin plays an important role in marginal adaptation.

The relationship between the course of enamel prisms and the direction of secretory face in Tomes' process of ameloblast was examined three-dimensionally in the dog tooth by light and electron microscopy, as well as by reconstruction. Scanning electron microscopic observation on the developing enamel surface after the dissolution of the enamel organ showed numerous groups of pits with bulbous faces inclined in the same sidewards direction, while those faces in neighboring groups were inclined in an opposite direction. Tangential semithin sections from demineralized tooth germs were serially cut from the enamel surface to the enamel-dentin junction. These sections showed numerous belt-like zones arranged perpendicular to the meridian of the tooth. A straight row of enamel prisms perpendicular to the boundaries of the belt-like zones was selected at 142 microns from the enamel-dentin junction. The row of prisms and their successive Tomes' processes were reconstructed from micrographs with a personal computer. The cut ends of the enamel prisms initially perpendicular to the boundaries appeared as a sine curve, viewed from the enamel-dentin junction. In a single belt-like zone, the horizontal tilt angles of the enamel prisms towards the enamel-dentin junction tended to be largest at the center of the zone, and smallest near the boundaries. The long axis of each enamel prism was at right angles to the secretory face of the Tomes' process. The secretory faces in a single belt-like zone were inclined in the same sidewards direction and the secretory faces in neighboring zones were inclined in opposite directions. The results suggest that the direction of the sidewards displacement in ameloblasts is related to that of the secretory face of Tomes' processes. Further, one group of ameloblasts with their secretory faces inclined in the same sidewards direction form one belt-like zone.

The caries-preventive effect of glass-ionomer sealant depends on both retention of sealant and fluoride release. In this study, the retention rate was maintained by sealant reapplication over three years. Caries reduction was 76.1 percent at one year, 69.9 percent at two years and 66.5 percent at three years. Reapplication is an acceptable procedure and seemed to improve caries reduction.

Addition of up to 300 microM ATP in the presence of 2 M NaCl with MgCl2 to pig kidney Na+,K+-ATPase treated with N-[p-(2-benzimidazolyl)phenyl]maleimide seemed to be insufficient to saturate the rate of the fluorescence decrease. However, both the extent of the decrease and the amount of phosphoenzyme at a steady state were saturated below 20 microM ATP. Addition of Mg2+ with Na+ to the enzyme preincubated with 20 to 600 microM ATP gave nearly the same rate constant, which was below 50% of that obtained by adding 300 microM ATP to the Na+-form enzyme in the presence of Mg2+. High concentrations of ATP affected neither the rate of light-scattering change (Taniguchi, K. et al. (1986) J. Biol. Chem. 261, 3272-3281) after ADP-sensitive phosphoenzyme formation (E1P) nor that of the breakdown of E1P. A stoichiometric amount of [32P]Pi was liberated from [32P]E1P. The data suggested that ATP did not bind to E1P in such a way as to increase the extent of phosphorylation further or to accelerate dephosphorylation. The data also suggested that the reason for the large difference in the apparent affinity of ATP as evaluated from the rate and the extent of fluorescence change is the large dissociation constant for ATP of a Michaelis complex.

The purpose of the present work was to study (1) the deformation of selected types of cavities in axially loaded human teeth and (2) the possible effect of this deformation on the restorative quality of fillings in the cavities. Recently extracted wet teeth without any visible structural defects were used throughout the study. Standard Class III and large Class III cavities were prepared in maxillary incisors, while Class I, m-o, m-o-d, and Class V cavities were made in maxillary first premolars. For the second part of the study several of the cavities, etched of non-etched, were filled with restroative resins. Mounted in a measuring microscope the teeth were loaded in a way simulating biting or chewing; cavities with fillings were accepted only when no marginal gaps could be found. The results showed a deformation of empty cavities proportional to the load up to 16 kg, the decrease or increase in diameter being 0.1-1.0 mum/kg, depending on the type of cavity. Loading and unloading of teeth with filled cavities resulted in permanent or transitory gaps. The dimensional instability of cavities in loaded teeth indicates a severe risk of percolation by several restoratives and of marginal fracture of brittle fillings.

The purpose of this paper was to study by means of scanning electron (SEM) and optical microscopy the adaptation of the low-viscous non-composite. Nuva-Seal and of the three high-viscous composite restorative materials Adaptic, Compocap and Concise to phosphoric acid etched enamel surfaces from symmetric areas of pairs of contralateral human permanent anterior teeth. The SEM study demonstrated that the two types of material equally well reproduce the details of the enamel surface; the light microscopic observations showed that the length and shape of resin tags in the enamel surface are independent of the materials examined. The observations seem to allow the conclusion that bonding of composite restorative resins to phosphoric acid etched enamel surfaces is not conditioned by the employment of an intermediate film of a low-viscous non-composite resin.

The experiments described lead to the conclusion that ionic iron enhances inflammatory responses with insufficient removal of carrageenin, and with insufficient granuloma formation probably due to a high degree of fibrinolysis. This non-adapted response may be due to the excessive production of lipid peroxide caused by ionic iron.

Trypsin treatment of N-[p-(2-benzimidazolyl)phenyl]maleimide modified enzyme caused a marked reduction in Na+,K+-ATPase activity and in the amount of the alpha-chain, which contains the phosphorylation and ouabain binding sites. However, these preparations retained nearly 90% of the ouabain binding capacity and showed ouabain sensitive dynamic fluorescence changes accompanying the hydrolysis of ATP. The data showed that the three dimensional structure of Na+,K+-ATPase, which is important in the dynamic fluorescence change, is little affected in spite of extensive covalent bond splitting in the alpha-chain of Na+,K+-ATPase.

Several observations have shown that contraction stresses in restorative resins bonded to the enamel of cavity walls readily broke the enamel surrounding the cavities. The forces studied were caused by polymerization contraction, thermal contraction or elastic hysteresis. The bonding was obtained mainly by etching the cavity walls by phosphoric acid.