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891.

Introduction

The repair of annular ligament after open reduction and internal fixation of radial head fracture could produce the irritation or crepitation during range of motion exercise. The purpose of this study is to evaluate the significance of unrepaired annular ligament during fixation of isolated radial head fractures.

Materials and methods

Retrospectively we reviewed the twenty-five patients who underwent surgical fixation with a plate for Mason type 2, 3 isolated radial head fracture without annular ligament repair. All the radial head fracture did not have the associated injuries which could cause the elbow instabilities. The average length of follow-up was 6.9 years. The outcomes were evaluated clinically (range of motions, instabilities, pain VAS, Broberg & Murrey functional rating score, DASH score) and radiographically (bony union, arthritic change, lateral translation of the radial head, humero-ulnar angle with maximum varus stress of elbow, ulnar variance).

Results

The range of motions between affected and contralateral side were not significantly different at last follow-up. No one showed the instabilities of elbow. The mean pain VAS, Broberg & Murrey functional rating score, and DASH score were 2.7 ± 0.5, 95.3 ± 2.5, and 14.8 ± 5.3 points respectively. Bony union was observed for all cases. There was no significant difference in the lateral translation of the radial head, humero-ulnar angle with maximum varus stress of elbow, and ulnar variance between the affected and the contralateral arm.

Conclusion

The isolated role of the annular ligament seems overestimated. We scrutinize that the annular ligament repair is not essential in the operative treatment of isolated radial head fractures if the lateral collateral ligament is intact.  相似文献   
892.

Objective

Biomechanical comparison between locked plating and retrograde nailing of supracondylar femur fractures with simulated postoperative weight-bearing.

Methods

The Locking Condylar Plate (LCP) and Retrograde/Antegrade EX Femoral Nail (RAFN) were tested using 10 paired elderly cadaveric femurs, divided into Normal and Low Bone Mineral Density (BMD) groups, with a simulated AO/OTA type 33-A3 supracondylar femur fracture. Each specimen was subjected to 200,000 loading cycles in an attempt to simulate six weeks of postoperative recovery with full weight-bearing for an average individual. The construct's subsidence due to cyclic loading, and axial stiffness before and after the cyclic loading were measured and their correlation with BMD was studied. The two implants were compared in a paired study within each BMD group.

Results

LCP constructs showed higher axial stiffness compared to RAFN for both Normal and Low BMD groups (80% and 57%, respectively). After cyclic loading, axial stiffness of both constructs decreased by 20% and RAFN constructs resulted in twice as much subsidence (1.9 ± 0.6 mm). Two RAFN constructs with Low BMD failed after a few cycles whereas the matched pairs fixed with LCP failed after 70,000 cycles.

Conclusions

The RAFN constructs experienced greater subsidence and reduced axial stiffness compared to the LCP constructs. In Low BMD specimens, the RAFN constructs had a higher risk of failure.  相似文献   
893.
Our hypothesis was that the incidence of malposition of a right‐sided double‐lumen endobronchial tube and right upper lobe collapse may increase when the distance between the carina and the distal margin of the right upper lobe orifice is less than 23 mm, measured from a computerised tomography scan. A total of 76 patients undergoing left‐sided thoracic surgery were enrolled. Patients with a measured distance of < 23 mm (n = 38) were compared with age‐, sex‐ and body mass index‐matched patients with a distance ≥ 23 mm (n = 38). Right‐sided double‐lumen endobronchial tubes were used universally. We monitored endobronchial tube malposition and incidence of right upper lobe collapse throughout surgery. There was a significantly higher incidence of bronchial cuff herniation in patients with a distance < 23 mm in both the supine position and the lateral decubitus position (p < 0.001). The incidence of intra‐operative malposition in the < 23 mm group was also significantly higher than in the ≥ 23 mm group (31 (82%) vs 8 (21%), respectively, p < 0.001). Right upper lobe collapse was detected postoperatively in five patients (13%) in the distance < 23 mm group, compared to none in the ≥ 23 mm group. We recommend that the distance between the carina and the distal margin of the right upper lobe bronchus should be routinely measured on the pre‐operative computerised tomography scan, and if it is < 23 mm, consideration should be given to using a left‐sided endobronchial double‐lumen tube in preference to a right‐sided one.  相似文献   
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Purpose

To cope with recipient portal vein (PV) anomalies, such as early branching of the right posterior section (RPS), during living donor liver transplantation (LDLT) surgery, we performed a simulation study to standardize the surgical technique for unification portal venoplasty.

Methods

This study included an observational analysis of conventional methods utilizing RPS PV, simulation-based design of a new surgical technique, and clinical application of this new technique.

Results

In a case encountering RPS PV, a mild anastomotic PV stenosis was persistent over 6 months postsurgery, indicating the need for technical refinement. After computational simulation analysis, we found that simple suturing of the PV branch patch automatically resulted in a funnel-shaped elongation. A prospective recipient study (n = 30) indicated that usual PV reconstruction via the PV bifurcation method is feasible in the absence of unusual donor or recipient PV anomaly. Retrospective living donor PV anatomy analysis (n = 20) revealed that 20-mm-long limbs of the first-order PV branches are necessary to make a 10- to l5-mm-long funneled PV stump. This technique of unification venoplasty for an anomalous recipient PV was applied to an adult patient undergoing LDLT with a right liver graft, for which it was shown to be technically feasible and effective.

Conclusions

A simplified unification venoplasty technique was developed to cope with a recipient PV anomaly in adult LDLT.  相似文献   
897.

Introduction

Various techniques have been described deceased donor liver transplantation (DDLT) procurement. One is a technique whereby almost total dissection is done in the porta hepatis and perihepatic detachment is carried out before cross-clamping the donor aorta. In another approach, after the donor aorta is cross-clamped, rapid and minimal en bloc dissection is performed with minimal manipulation. We evaluated early posttransplant graft function among liver procurement techniques.

Method

Between January 2008 and August 2012, we performed 45 consecutive adult DDLTs. One patient was excluded from this analysis due to early death from sepsis after transplantation. The 44 included patients were divided into two cohorts according to the procurement technique: A warm dissection (n = 23; 52%) and a cold dissection group (n = 21; 48%). We compared early posttransplant graft function using the aspartate aminotransferase (AST), alanine aminotransferase (ALT), total bilirubin (T-bil), and prothrombin time (PT) values of the two groups from the first to seventh postoperative day.

Result

The AST values in the warm group were significantly greater than those in the cold group on postoperative days 3 and 5. In addition, the ALT values in the warm group were greater than those in the cold group on postoperative days 4, 5, and 6. Moreover, the T-bil values in the warm group were greater than those in the cold group on postoperative days 2, 3, 4, 5, 6, and 7. However, there were no differences in PT values.

Conclusion

During liver procurement for DDLT, rapid en bloc procurement with minimal manipulation after clamping the donor aorta achieved better early graft function posttransplantation.  相似文献   
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