A New Harvest Site for Bone Graft in Anterior Cruciate Ligament Revision Surgery

During revision anterior cruciate ligament (ACL) surgery, femoral interference screws frequently require removal. This may lead to significant tunnel widening and possible graft fixation failure as a result. Solutions include drilling the revision tunnel in a different location, using stacked interference screws, or using bone graft to fill the defect. Autogenous iliac crest graft and allograft are both used, but there are significant comorbidities associated with each. We developed a new technique for harvesting autogenous bone graft that avoids many of the complications associated with other graft sources. By use of the existing surgical incision from the initial harvest of the bone–patellar tendon–bone autograft, bone from the medial tibial metaphyseal safe zone is harvested via an OATS tube harvester (Arthrex, Naples, FL). A bone plug 1 mm larger in size than the femoral defect is harvested and arthroscopically inserted via a press-fit technique. At 3 months after bone grafting, patients undergo revision ACL reconstruction. The proximal tibial metaphysis is a safe bone graft harvest site in revision ACL surgery and offers an effective method for filling large bony defects, allowing anatomic reconstruction of the ACL after bone healing has occurred. Furthermore, it eliminates the problems associated with allograft or use of a remote graft donor site.     

大白鼠皮肤Ⅱ度、Ⅲ度碱烧伤模型复制

目的 根据大白鼠皮肤碱烧伤创面早期病理组织学观察复制Ⅱ、Ⅲ度碱烧伤模型,研究碱烧伤的临床治疗.方法 Wistar纯种健康大白鼠20只,以不同浓度2mol/l、2.5mol/l、5mol/lNaOH,作用时间分别为30秒、45秒、60秒、75秒,涂抹于脱毛后的表皮.结果 2mol/L(60s)、2.5mol/L(45s),5mol/L(30s)即可直接造成Ⅱ度～深Ⅱ度烧伤;2mol/L(75s)、2.5mol/L(60s)、5 mol/L(45s)即可造成Ⅲ度烧伤,其烧伤深度与NaOH溶液浓度和作用时间呈正比.结论 Ⅱ度、Ⅲ度碱烧伤均为渐进性烧伤,与文献中介绍的潜拙样损伤似乎不同.另外,不同浓度NaOH溶液在相同时间对皮肤组织的损伤及同一浓度NaOH溶液在不同时间对大白鼠皮肤的损伤病理学变化均有差异.     

Aortic prosthetic ring annuloplasty: a useful adjunct to a standardized aortic valve-sparing procedure?

OBJECTIVE: Dilation of aortic annulus, sinuses of Valsalva, and sinotubular junction (STJ) diameters are the characteristic lesions of aortic root aneurysm. The remodeling technique reduces STJ diameter and creates three neosinuses of Valsalva. Alternatively, the reimplantation technique reduces both annulus and STJ diameters to the detriment of aortic root dynamics. Although the remodeling technique is recognized as the most physiological valve-sparing procedure, aortic annulus dilation may jeopardize its results. A standardized approach that combines an external subvalvular aortic prosthetic ring annuloplasty with the remodeling technique is suggested. METHODS: Eighty-three patients underwent an elective aortic root remodeling procedure, either isolated (group 1, n=34) or combined with an external subvalvular aortic prosthetic ring annuloplasty (group 2, n=49). Preoperative aortic regurgitation was 1.59+/-1.1 (group 1) and 1.97+/-1.3 (group 2) (NS). The aortic annulus was more dilated in group 2 than in group 1 (27+/-2.77 mm vs 26.4+/-2.3 mm, p<0.01). Residual aortic regurgitation > or =grade II was the conversion criteria for aortic valve replacement. RESULTS: Operative mortality was 3.6% (n=3). Intraoperative conversion for valve replacement was 32.7% in group 1 (n=11) versus 4.2% in group 2 (n=2) (p<0.001). In group 1, preoperative annulus diameter was larger for converted than for valve-spared patients (27.6+/-1.7 mm vs 25.2+/-1.5 mm, p<0.02). In group 2, implanted aortic ring significantly reduced annulus diameter (20.6+/-1.8 mm) without significant aortic valve gradient (8.3+/-3 mmHg). Follow-up was 17.2+/-13.4 months (group 1) and 10.41+/-7.95 months (group 2). Reoperation for recurrent aortic regurgitation was 13% in group 1 (n=3) versus 4.2% in group 2 (n=2). Echocardiographic follow-up found residual aortic regurgitation < or =grade I in 17 patients in group 1 (90%) versus 43 patients in group 2 (95.5%) and of grade II in two patients in group 1 (10%) and two patients in group 2 (4.5%). CONCLUSION: The addition of external aortic prosthetic ring annuloplasty improves the remodeling technique's operative reproducibility and short-term results. Therefore, its use as a systematical adjunct to the remodeling procedure is suggested. However, further long-term evaluation comparing this valve-sparing procedure to composite graft replacement should define the best surgical strategy for aortic root aneurysm.