中下段颈椎的应力松弛特性及前、后路手术对其的影响

目的 研究中下段颈椎的应力松弛特性，并评估椎间盘切除植骨术与椎板切开术对其影响。方法 6例新鲜尸体完整颈椎及手术后颈椎，在模拟生理状态下进行屈曲及伸展位的应力松弛实验。结果 在恒应变条件下，绘制术前及不同术式后的中下段颈椎的应力松弛函数及曲线；术后的中下段颈椎的应力和初始化应力比值G(t)比术前明显增大，前路椎间盘切除植骨术后的G(t)值比椎板切开术大，两者均有统计学意义。结论 在恒应变条件下，颈椎具有快速应力松弛敏感性，屈曲位比伸展位大。椎板成形术及颈椎前路椎间盘切除植骨术都使颈椎的应力松弛能力减弱，前路椎间盘切除植骨术的影响更大。     

Anterior Cruciate Ligament Reconstruction: State of the Art

Abstract The rupture of the Anterior cruciate ligament (ACL) belongs to the most common ligament injuries of the human knee joint. ACL rupture results in an increased anterior translation and internal rotation of the tibia. Untreated knee instability causes a disintegration of the roll and sliding movement and a high incidence of secondary meniscus and chondral damages with consecutive or advanced arthritic changes. For deciding on a conservative or operative therapy, it is necessary to develop a high-risk profile. Elderly, inactive patients without instability symptoms can be treated conservatively; younger, active people and complex ligament injuries should receive an ACL replacement. The goal is to eliminate instability by maintaining the physiological kinematics of the knee. Anterior cruciate ligament may be reconstructed arthroscopically assisted by autologous tendons. Predominantly, hamstring- and bone-patellar-tendon grafts are used. No significant differences in knee laxity, clinically and functionally, were observed between both grafts. Various reconstruction techniques, single- or double-bundle techniques, were described. Successful replacement depends on a correct tunnel placement and reconstruction of the physiological band tension, a sufficient mechanical stability of fixation, an impingement-free range of motion and an adequate rehabilitation. A high degree of patient satisfaction in clinical and functional outcome could be evaluated.     

Hybrid Anterior Cruciate Ligament Reconstruction: Introduction of a New Technique for Anatomic Anterior Cruciate Ligament Reconstruction

Recently, anatomic or double-bundle reconstruction of the anterior cruciate ligament (ACL) has been presented in an effort to more accurately restore the native anatomy. These techniques create 2 tunnels in both the femur and tibia to reproduce the bundles of the ACL. However, the increased number of tunnels, particularly on the femoral side, has raised some concerns among authors and surgeons. We describe a technique to reconstruct the 2 distinct bundles of the ACL by using a single femoral tunnel and 2 tibial tunnels, the “hybrid” ACL reconstruction. The femoral tunnel is drilled through an anteromedial arthroscopy portal, which allows placement in a more anatomic position. Fixation in the femur is achieved with a novel device that separates a soft-tissue graft into 2 independently functioning bundles. Once fixed in the femur, the anteromedial and posterolateral bundles of the graft are passed through respective tunnels at the anatomic footprint on the tibia. These bundles are independently tensioned, which creates a reconconstruction that is similar to the native ACL. The technique presented provides surgeons with an alternative to other double-bundle techniques involving 4 tunnels.     

Arthroscopic Coracoclavicular Ligament Reconstruction Using Biologic and Suture Fixation

Presented in this report is a modified arthroscopic approach to acromioclavicular joint reconstruction via suture and allograft fixation. An arthroscopic approach is used to expose the base of the coracoid by use of electrocautery. After an open distal clavicle excision is performed, clavicular and coracoid tunnels are created under arthroscopic visualization as previously described by Wolf and Pennington. The myotendinous end of a semitendinosus allograft is sutured to a Spider plate (Kinetikos Medical, San Diego, CA). The tendinous end of the graft is prepared with a running baseball stitch. A Nitinol wire with a loop end (Arthrex, Naples, FL) is used to pass 2 free FiberTape sutures (Arthrex) and the leading sutures from the tendinous end of the graft through the clavicular and coracoid tunnels, exiting out the anterior portal. One of the FiberTape sutures is retrieved with a grasper and passed over the anterior aspect of the distal clavicle. The second FiberTape suture and the allograft are passed over the distal end of the resected clavicle. While the acromioclavicular joint is held reduced, the FiberTape sutures are tied to the plate and the allograft is tensioned medially until the plate is embedded against the superior surface of the clavicle. The tendinous end of the graft is secured to the superior surface of the clavicle with a Bio-tenodesis screw (Arthrex) medial to the clavicular tunnel.     

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.