Biomechanical Analysis of a Novel Wedge Locking Plate in a Porcine Tibial Model

BACKGROUND: The purpose of this study was to analyze biomechanical properties of a novel wedge locking plate in medial open wedge high tibial osteotomy (OWHTO) in a porcine tibial model. METHODS: A uniform 8-mm OWHTO was performed in 12 porcine tibiae. Six of them were subsequently fixed with the plate without a wedge, whereas the other 6 were additionally reinforced with a metal wedge of 8 mm. Biomechanical properties (stiffness, displacement of the osteotomy gap, and failure load) were evaluated under axial load. The different modes of failure were also investigated. RESULTS: The plate showed an axial stiffness of 2,457 ± 450 N/mm with a wedge and 1,969 ± 874 N/mm without a wedge. The maximum failure load was 5,380 ± 952 N with a wedge and 4,354 ± 607 N without a wedge. The plate with a wedge had a significantly greater failure load and significantly less displacement of medial gap at failure than that without a wedge (p = 0.041 and p = 0.002, respectively). The axial stiffness was not different between the two types of fixation. Most failures were caused by lateral cortex breakage and there was no implant failure. CONCLUSIONS: The novel wedge locking plate showed excellent biomechanical properties and an additional wedge provided significant improvement. This plate can be a good fixation method for OWHTO.

Prediction of Motor Recovery Using Diffusion Tensor Tractography in Supratentorial Stroke Patients With Severe Motor Involvement

OBJECTIVE: To investigate whether early stage diffusion tensor tractography (DTT) values predict motor function at 3 months after onset in supratentorial stroke patients with severe motor involvement. METHODS: A retrospective study design was used to analyze medical records and neuroimaging data of 49 supratentorial stroke patients with severe motor involvement. Diffusion tensor imaging was assessed within 3 weeks after stroke in all patients. Three-dimensional tractography of the ipsilateral corticospinal tract (CST) was performed using the fiber assignment of the continuous tracking algorithm. The two-step DTT analysis was used. The first step was classification according to ipsilateral CST visualization. The second step was a quantitative analysis of the visible-CST group parameters. Motor function was assessed at 2 weeks and at 3 months after stroke. Comparative and correlation analyses were performed between DTT-derived measures and motor assessment scores. RESULTS: Motor function of the upper extremity at 3 months after stroke was significantly higher in the visible-CST group than that in the nonvisible-CST group (p<0.05). Early stage fractional anisotropy was of DTT correlated significantly with upper extremity motor function at 3 months after stroke in the visible-CST group (p<0.05). CONCLUSION: These results demonstrate that early DTT-derived measures predict motor recovery in the upper extremity at 3 months after onset in supratentorial stroke patients with severe motor involvement.

Biomechanical Properties of a New Anatomical Locking Metal Block Plate for Opening Wedge High Tibial Osteotomy: Uniplane Osteotomy

PURPOSE: The purpose of this study was to evaluate the biomechanical properties of a new anatomical locking metal block plate by comparing the initial biomechanical stability of three different fixation constructs for open wedge high tibial osteotomy (HTO). MATERIALS AND METHODS: Sawbones composite tibiae were used to make a 10-mm opening osteotomy model with uniplane technique. The osteotomy was secured with three different types of plates: Group I, new osteotomy plate without a metal block (n=5); Group II, new osteotomy plate with a 10-mm metal block (n=5); and Group III, two short metal block plates (n=5). Single load to failure test and staircase load-controlled cyclical failure test were performed. In the single load to failure test, the yield load, maximum failure load, and the displacement of the osteotomy gap were measured. In the staircase cyclical load to failure test, the total number of cycles to failure was recorded. Failure modes were observed during both single and cyclic load tests. RESULTS: Group II showed the highest yield and ultimate loads (1829+/-319 N, 3493+/-1250 N) compared to Group I (1512+/-157 N, 2422+/-769 N) and Group III (1369+/-378 N, 2157+/-210 N, p<0.05). The displacement of the opening gap in Group II (0.34+/-0.35 mm) was significantly lesser than the other groups (p<0.05). In the staircase cyclical load to failure test, the total number of cycles to failure was 12,860 at 950 N in Group III, 20,280 at 1,140 N in Group I, and 42,816 at 1,330 N in Group II (p<0.05). All the specimens showed complete fracture of the intact lateral sawbones area and slight displacement of the distal fragment of the specimens in the single load to test. None of the specimens showed deformed or broken screws and plates during the single load to test. During the fatigue test with staircase cyclic loading, no fracture of the lateral sawbones area was observed. CONCLUSIONS: This study demonstrated that the new anatomical locking metal block plate could provide sufficient primary stability for open wedge HTO. The addition of a metal block to this new plate can increase the stability of the osteotomy compared to the one without a metal block.

White Matter Hyperintensities and Cognitive Dysfunction in Patients With Infratentorial Stroke

OBJECTIVE: To determine whether cognitive function is associated with white matter hyperintensities (WMH) in patients with infratentorial stroke. METHODS: This was a retrospective, cross-sectional study. Twenty-four first-ever infratentorial stroke patients between 18 and 60 years of age were enrolled. WMH was evaluated by the Fazekas scale and the Scheltens scale. Cognitive functions were assessed using the Korean Mini-Mental Status Examination (K-MMSE), Rey-Osterrieth Complex Figure Test, and the Seoul Computerized Neuropsychological Test Battery (SCNT) at one month after stroke. All participants were divided into two groups based on the presence of WMH (no-WMH group and WMH group). General characteristics and cognitive functions were compared between the groups. RESULTS: There were no significant differences in general characteristics, such as age, stroke type, hypertension history, and education level between the two groups. However, K-MMSE in the WMH group was significantly lower compared to the no-WMH group (p<0.05). The verbal learning test score in SCNT was significantly higher in the no-WMH group compared to the WMH group (p<0.05). Executive function in the no-WMH group tended to be higher compared to the WMH group. CONCLUSION: Impairment of cognitive function in patients with infratentorial stroke appeared to be associated with WMH. WMH should be carefully evaluated during rehabilitation of infratentorial stroke patients.

Two Cases of Gastritis Cystica Superficialis without Previous Gastric Surgery / 대한소화기내시경학회지

Gastritis cystica superficialis (GCS) is a rare lesion which is characterized by glandular hyperplasia with regeneration and degeneration in the mucosa and muscularis mucosa. Recently, GCS is revealed as precancerous lesion, but most report has been associated with those found at the site of a gastroenterostomy. So, we report two cases with GCS who had not previous gastric surgery. A 45-year-old woman visited for epigastric discomfort and another 4Q-year-old woman for epigastric pain. They had not undergone any gastric surgery. The gastroscopy discovered one polyp on anterior wall of greater curvature, upper body and another polyp in the center of the fold of greater curvature, lower body. We removed it by snare polypectomy and the histologic finding showed the character of GCS.

Efficacy of Blood Urea Nitrogen/Creatinine Ratio in Distinguishing Upper from Lower Gastrointestinal Bleeding / 대한소화기내시경학회지

BACKGROUND/AIMS: When stools containing altered blood are the sole evidence for acute gastrointestinal bleeding, the bleeding source is uncertain. Because the absorption of blood products via the small intestine is responsible for azotemia after gastrointestinal bleeding, patients with colorectal bleeding rarely become azotemic. Therefore the blood urea nitrogen to creatinine ratio (BUN/Cr ratio) is believed to reliably discriminate upper gastrointestinal bleeding (UGIB) from lower gastrointestinal bleeding (LGIB). This study was conducted to evaluate the BUN/Cr ratio for distinguishing an upper versus lower source of gastrointestinal bleeding. METHODS: Charts of patients who were admitted to Maryknoll hospital with the diagnosis of gastrointestinal bleeding from August 1994 to August 2000, were retrospectively reviewed for source of bleeding, initial blood urea nitrogen (BUN), creatinine (Cr), BUN/Cr ratio, hemoglobin, and hematocrit. RESULTS: A total of 298 patients were eligible for inclusion, 210 (70%) of whom were male. A total of 168 (56%) patients had an UGIB. Gastric ulcer disease (42%) and esophageal varices (27%) were the most common causes of UGIB, whereas malignant neoplasm was etiologic in 29% of LGIB episodes. The mean standard deviation BUN/Cr ratio was significantly higher in UGIB than LGIB (34.1+/-12.9 vs. 12.2+/-; p<01). CONCLUSIONS: The BUN/ Cr ratio may be a useful tool in distinguishing upper from lower sources of gastrointestinal bleeding, especially in patients with an uncertain source that could be upper or lower in origin.

A Case of Solitary Cecal Diverticulitis Misdiagnosed as a Cecal Tumor / 대한소화기내시경학회지

Cecal diverticulitis is a rare entity and remains a difficult diagnostic problem. Most patients are presented with an acute pain in the abdomen, which is nearly indistinguishable from that of appendicitis. Preoperative diagnostic studies are not helpful. Even with an operation, the correct diagnosis may be difficult to predict with certainty. The differential diagnosis between a cecal malignant tumor and a mass caused by inflammation due to cecal diverticulitis is difficult. Suspicion of a neoplastic process continues to prompt colectomy in an emergency setting. If diagnosed preoperatively, it can be treated effectively with a broad spectruum of antibiotics without surgical intervention. The physician must be aware this condition and be prepared to choose the most apropriate treatmetn. A case was experienced involving of solitary cecal diverticulitis misdiagnosed as a cecal tumor in a 61-year-o0ld female. This unique form of diverticulitis is herein reported with literature review.

A Case of Colonic Angiodysplasia in Massive Lower Gastrointestinal Bleeding / 대한소화기내시경학회지

Colonic angiodysplasia is important because of the likelihood of lower gastrointestinal tract bleeding, either massively or chronically. A 66-year-old male patient visited our hospital because of hematochezia and lower abdominal discomfort. He underwent colonoscopy, which revealed 0.5 cm sized, cherry red colored, branching, ozzing vessel with fern-like margin on cecum. Although he received endoscopic injection therapy with hypertonic saline and oral estrogen-progesterone therapy, subsequent ileocecal resection was performed due to recurrent bleeding. Histology of the resected specimen showed irregularly dilated, distorted, thin-walled vessels in submucosa.

A Case of Anti-Glomerular Basement Membrane Antibody Associated Crescentic Glomerulonephritis with Positive Antineutrophilic Cytoplasmic Antibody / 대한신장학회잡지

A 63-year-old woman presented to the hospital with gross hematuria and acute renal failure. Kidney function deteriorated rapidly and progressively. A renal biopsy revealed segmental or circumferential crescents associated with linear deposits of immunoglobulin G, typical of anti-glomerular basement membrane disease. Both c-ANCA and anti-GBM antibody were detected in serum. She was treated with hemodialysis, plasmapheresis, high dose steroid and cyclophosphamide. However, she died 7 weeks after treatment because of pneumonia, without recovery of renal function. Serologic positivity of both ANCA and anti-GBM antibody are becoming more frequently recognized in rapidly progressive glomerulonephritis. The influence of c-ANCA on the clinical course of anti-GBM glomerulonephritis remains to be determined.

A Case of Bleeding Jejunal Tuberculosis Diagnosed with Intraoperative Endoscopy / 대한소화기내시경학회지

Tuberculosis is a multi-organ disease. The incidence of pulmonary tuberculosis is declining due to improvement in public health, vaccination and the development of anti-tuberculosis medication, but extrapulmonary tuberculosis has become more common, especially in immuno-compromised individuals, AIDS patients and immigrants to western worlds. Gastrointestinal tuberculosis continues to give rise to diagnostic and therapeutic challenges. The jejunal tuberculosis is uncommon and presents a difficult diagnostic problem. Bleeding jejunal tuberculosis is a very rare source of lower gastrointestinal bleeding. We have recently experienced a case of a jejunal tuberculosis which was proven to be a source of gastrointestinal bleeding by intraoperative endoscopy and was confirmed by surgical exploration. This report summarized our experience and review of literature.

A case of Primary Hemangiopericytoma of the Lung / 결핵

Primary hemangiopericytomas of the lung are uncommon sarcomas that arise from pericytes that surround the basement membrane of capillaries and small venules within the lung parenchyma. The presenting symptoms and signs depend on the location of the tumor and radiologic features are not diagnostic. The behavior of pulmonary hemangiopericytomas is difficult to predict and all tumors should be considered potentially malignant. Wide surgical excision remains the mainstay of treatment. We report a case of primary hemangiopericytoma of the lung with a brief review of literature.

Isolated Heterotopic Gastric Mucosa of the Upper Esophagus / 대한소화기내시경학회지

BACKGROUND: Isolated heterotopic gastric mucosa of the upper esophagus(HGME), often referred to as inlet patch, is an asyptomatic benign lesion. It may, however, cause retrosternal chest pain and dysphagea, and rarely produce complications such as ulceration and stricture. It may be suspected on characteristic finding of endoscopy, and the diagnosis is usually proved by biposy. We studied several characteristics of HGME. METHOD: From January 1996 to May 1997, endoscopy was performed on 2000 consecutive patients (1068 male, 932 female). HGME was seen 25 patients(12 male, 13 female) among 2000 patients. RESULT: Prevalence of HGME is 1.25%. There was no significant difference of the prevalence of HGME between male and female. HGME was presented as a velvety and salmon-pink patch with a distict border from the normally pale squamous cell mucosa of the esophagus, and was seen as multiple lesions in 8 patients among 25 patients. Thirty three locailzed gastric mucosal patches, varying in size 3 mm to 30 mm in the longest diameter, were detected within or just below of upper esophageal spincter in all the twenty five patients. Biopsy specimens taken from the miucosal patches demonstrated gastric mucosa. Among 25 patients with HGME, four patients complained foreign body sensation on throat or heartburn, without other diseases such as GERD, gastritis or peptic ulcer. CONCLUSION: Further studies of a large scale about pathogenesis, prevalence, and complication of HGME will be required.