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61.
BACKGROUND: We hypothesized that a dorsomedial locking plate with adjunct screw compression would provide superior rigidity compared to crossed screws for first metatarsocuneiform (MTC) arthrodesis. MATERIALS AND METHODS: In ten matched lower extremity pairs, specimens in each pair were randomly assigned to receive screw fixation or plate with screw fixation. Bone mineral density (BMD) was measured. For the crossed-screw construct, two 4.0-mm cannulated screws were used. One screw was inserted dorsal to plantar beginning from the first metatarsal 10 to 15 mm distal to the joint, and the second was inserted from the cuneiform 8 to10 mm proximal to the joint, medial to the first screw, into the first metatarsal. For the plate construct, a 4.0-mm cannulated compression screw was inserted from the dorsal cortex of the first metatarsal to the plantar aspect of the medial cuneiform. A locking plate was inserted dorsomedially across the MTC joint. Specimens were loaded in four-point bend configuration (displacement rate, 5 mm/min) until failure of the fixation or 3-mm deformation. An extensometer was used to measure deformation. RESULTS: There was no difference in load to failure or stiffness between the two groups. BMD was positively correlated with load to failure in the screw (r = 0.893, p = 0.001) and the plate (r = 0.858, p = 0.001) construct. CONCLUSION: The plate construct with compression screw did not show different rigidity as compared with the screw construct with the numbers available. CLINICAL RELEVANCE: Further investigation of a dorsomedial plate with adjunct screw compression may be warranted for first MTC arthrodesis.  相似文献   
62.
In patients with brachial plexus birth palsy, persistent muscular imbalance across the developing shoulder results in progressive glenohumeral dysplasia, characterized by increased glenoid retroversion, humeral head flattening, and posterior subluxation of the humeral head. Soft-tissue procedures-such as tendon transfers and musculotendinous lengthenings--will provide limited functional improvements in the setting of advanced glenohumeral deformity. For patients with internal rotation contracture and external rotation weakness associated with severe glenohumeral dysplasia, external rotation osteotomy of the humerus may be used to improve global shoulder function. The purpose of this article is to review the history, indications, and surgical technique of external rotation humeral osteotomy for patients with brachial plexus birth palsy.  相似文献   
63.
Bae YC  Kim JH  Lee J  Hwang SM  Kim SS 《Annals of plastic surgery》2002,48(4):359-62; discussion 362-4
Palatal lengthening is often emphasized in performing palatoplasty. However, definitive data regarding the method of measuring palatal length and the extent of palatal lengthening expressed quantitatively have not been reported. The authors have devised an easy method of measuring palatal length that can be expressed quantitatively, and they examined the characteristics of various methods of palatoplasty that are presently used commonly. A paper ruler was used to measure both a straight-line and a curved distance while the patient was under general anesthesia before and immediately after the palatoplasty. According to this study, the straight-line distance was lengthened to a significantly greater degree than the curved distance was after pushback palatoplasty for incomplete types of cleft palate and two-flap palatoplasty for complete types. Furlow double-opposing Z-palatoplasty and two-flap palatoplasty appeared to allow for greater palatal lengthening than the pushback palatoplasty. Further investigations will be undertaken to determine the correlation between the extent of palatal lengthening and speech development.  相似文献   
64.
Background Endoscopic resection (ER) is an effective treatment for early gastric cancer (EGC) without lymph node metastasis. However, after ER additional surgery may be needed to manage the risks presented by residual cancer or lymph node metastasis. Methods ER was performed on 344 gastric adenocarcinomas between November 2001 and April 2006 at the Korean National Cancer Center under the strict pre-procedural indication. The authors performed operations in 43 patients due to: residual mucosal cancer, a mucosal cancer larger than 3 cm, or a submucosal cancer regardless of size or margin involvement. ER and surgical specimens were reviewed and analyzed for residual cancer and lymph node metastasis. Results Based on examinations of ER specimens, cancer was confined to the mucosal layer in 15 patients (34.9%) and invaded the submucosal layer in 28 patients (65.1%). Surgical specimens showed residual cancer in 17 patients (39.5%) and lymph node metastasis in four (9.3%). Neither residual cancer nor lymph node metastasis was found in patients with less than 500 μm submucosal invasion without margin involvement in ER specimens. In three of four patients with lymph node metastasis, the depth of submucosal invasion was 500 μm or more; the remaining patient had a 4-cm-sized differentiated mucosal cancer. Conclusions When a pathologic evaluation of an ER specimen reveals more than 500 μm of submucosal invasion or a mucosal cancer of larger than 3 cm, surgery should be considered due to the risk of lymph node metastasis.  相似文献   
65.
We report a case of ceramic liner fracture in a 34-year-old man that occurred 1 year 9 months after total hip arthroplasty with a BiCONTACT (Aesculap, Tuttlingen, Germany) ceramic-on-ceramic prosthesis. The ceramic liner was found within the metal shell in 4 large pieces and multiple small fragments in the peripheral portions. Its condition indicated that the possible mechanism of late ceramic liner chip fracture was repeated episodes of impingement between the prosthetic neck and the edge of the ceramic liner. Squatting, kneeling, and sitting cross-legged caused impingement. These positions are more common in Asian populations than in Western populations. After the joint was thoroughly irrigated, a new modular ceramic liner and a 28-mm ceramic head were implanted.  相似文献   
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68.
BACKGROUND: Derotational humeral osteotomies have been used in older children with brachial plexus birth palsy and glenohumeral joint deformity to place the upper extremity in a more functional position. The purpose of this study was to determine the effects of these procedures on shoulder function and joint morphology. METHODS: Forty-three patients underwent a derotational humeral osteotomy for functional impairment in the setting of internal rotation contracture and/or glenohumeral joint deformity at our institution from 1996 to 2004. Osteotomies were performed proximal to the deltoid insertion and were stabilized with plate-and-screw fixation. The average age of the patients at the time of surgery was 7.6 years (range, 2.3 to 17.0 years). Shoulder function was graded according to the modified Mallet classification system. Glenohumeral deformity was graded according to the classification scheme of Waters et al. The results for twenty-seven patients who were followed for a minimum of two years (average, 3.7 years) are reported. RESULTS: The average amount of external rotation achieved with osteotomy was 64 degrees (range, 35 degrees to 90 degrees). The mean aggregate Mallet classification score improved from 13 to 18 points (p < 0.01). The mean Mallet classification scores for the individual elements similarly demonstrated improvement following osteotomy, with the greatest gains in hand-to-mouth, hand-to-neck, and external rotation motions. The mean classification of the glenohumeral deformity was type IV preoperatively and postoperatively, signifying the persistence of glenohumeral dysplasia. There were no nonunions. One patient required a revision osteotomy for inadequate initial correction. One patient sustained a humeral fracture distal to the plate fixation because of sports-related trauma. CONCLUSIONS: Derotational humeral osteotomy improves shoulder function in patients with brachial plexus birth palsy, internal rotation contracture, and/or advanced glenohumeral joint deformity. This osteotomy provides an attractive treatment option for patients with brachial plexus birth palsy who have advanced glenohumeral dysplasia precluding soft-tissue releases and tendon transfers.  相似文献   
69.
OBJECTIVE/SUMMARY BACKGROUND DATA: Serial transverse enteroplasty (STEP) is a new intestinal lengthening procedure that has been shown to clinically increase bowel length. This study examined the impact of the STEP procedure upon intestinal function in a model of short bowel syndrome. METHODS: Young pigs (n=10) had a reversed segment of bowel interposed to induce bowel dilatation. Five pigs underwent a 90% bowel resection with a STEP procedure on the remaining dilated bowel while 5 served as controls and had a 90% bowel resection without a STEP procedure. Determinations of nutritional status, absorptive capacity, and bacterial overgrowth were conducted 6 weeks after resection. Statistical comparisons were made by 2-sample t test (significance at P<0.05). RESULTS: The STEP procedure lengthened the bowel from 105.2+/-7.7 cm to 152.2+/-8.3 cm (P<0.01). The STEP animals showed improved weight retention compared with controls (mean, -0.5%+/-1.8% body weight versus -17.6%+/-1.5%, P<0.001). Intestinal carbohydrate absorption, as measured by d-Xylose absorption and fat absorptive capacity as measured by serum vitamin D and triglyceride levels, were increased in the STEP group versus controls. Serum citrulline, a marker of intestinal mucosal mass, was significantly elevated in the STEP pigs compared with controls. None of the STEP animals but 4 of 5 control animals were noted to have gram-negative bacterial overgrowth in the proximal bowel. CONCLUSIONS: STEP improves weight retention, nutritional status, intestinal absorptive capacity, and serum citrulline levels in a porcine short bowel model. A salutary effect upon bacterial overgrowth was also noted. These data support the use of this operation in short bowel syndrome.  相似文献   
70.
A decline in renal function suggests progression of chronic kidney disease. This can be determined by measured GFR (e.g., iothalamate clearance), serum creatinine (SCr)-based GFR estimates, or creatinine clearance. A cohort of 234 patients with autosomal dominant polycystic kidney disease and baseline creatinine clearance>70 ml/min were followed annually for four visits. Iothalamate clearance, SCr, and creatinine clearance were obtained at each visit. Estimated GFR (eGFR) was determined with the Modification of Diet in Renal Disease (MDRD) and Cockcroft-Gault equations. Renal function slopes had a mean residual SD of 10.7% by iothalamate clearance, 8.2% by MDRD equation, 7.7% by Cockcroft-Gault equation, and 14.8% by creatinine clearance. By each method, a decline in renal function (lowest quintile slope) was compared among baseline predictors. Hypertension was associated with a decline in iothalamate clearance (odds ratio [OR] 5.8; 95% confidence interval [CI] 2.3 to 14), eGFR (OR [MDRD] 2.0 [95% CI 1.0 to 4.2] or OR [Cockcroft-Gault] 1.9 [95% CI 0.9 to 3.9]), and creatinine clearance (OR 2.0; 95% CI 1.0 to 4.2). Each doubling of kidney volume at baseline was associated with a decline in iothalamate clearance (OR 2.4; 95% CI 1.5 to 3.7), eGFR (OR 1.7 [95% CI 1.1 to 2.6] or 2.1 [95% CI 1.4 to 3.3]), and creatinine clearance (OR 1.7; 95% CI 1.1 to 2.5). Predictor associations were strongest with measured GFR. Misclassification from changes in non-GFR factors (e.g., creatinine production, tubular secretion) conservatively biased associations with eGFR. Misclassification from method imprecision attenuated associations with creatinine clearance.  相似文献   
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