BACKGROUND Triple-threaded, cannulated headless screws of varying thread diameters and pitch are designed to maintain thread length across the arthrodesis plane, provide joint compression, and reduce countersinking. This study tested the biomechanical fixation strength of conventional partially threaded lag screws compared to triple-threaded headless screws in first metatarsophalangeal joint ar...

The following paper talks about the dynamic modeling and control of robot manipulators using Hamilton’s equations in screw theory framework. difference between proposed work with diverse methods literature is ease obtaining laws directly screws co-screws, which considered modern robotics by authors. In addition, geometric algebra (GA) introduced as a simple iterative tool to obtain co-screws. O...

BACKGROUND The pullout strength of pedicle screws is influenced by many factors, including diameter of the screws, implant design, and augmentation with bone cement such as PMMA. In the present study, the pullout strength of an innovative fenestrated screw augmented with PMMA was investigated and was compared to unaugmented fenestrated, standard and dual outer diameter screw. METHODS Twenty f...

The ability of various screw types to stabilize depressed tibial plateau fractures was determined in a biomechanical study using a Sawbones model. Two sizes of both cancellous and cortical screws were evaluated for both supportfrom below and through the depressed fragment. As a general trend, cancellous bone screws provided a greater resistance to fragment displacement than cortical bone screws...

PURPOSE To evaluate the insertion torque of a soft-tissue interference screw in relation to depth of insertion into the tibial tunnel when used for fixation of a quadrupled semitendinosus-gracilis autograft in anterior cruciate ligament reconstruction. TYPE OF STUDY Biomechanical cadaver study. METHODS Ten quadrupled semitendinosus-gracilis grafts were harvested from fresh-frozen cadaver kn...

OBJECTIVE To present the clinical benefits of an instrument designed to facilitate removal of polyaxial screws during revision surgery. METHODS All polyaxial screws can be removed without additional materials or a large amount of debridement using our newly designed instrument. Forty-two screws were removed from five patients without any complications using this instrument. RESULTS We remov...

OBJECT Intraoperative imaging often does not provide adequate visualization to ensure safe placement of screws. Therefore, the authors investigated the accuracy of a freehand technique for placement of pars, pedicle, and intralaminar screws in C-2. METHODS Sixteen cadaveric specimens were instrumented freehand by 2 experienced cervical spine surgeons with either a pars or pedicle screw, and b...

Background: Anterior cruciate ligament (ACL) reconstruction using tendon or ligament autograft is the current goldstandard surgical technique for acute ACL ruptures. However, ACL repair surgical procedures are reappearing as anoptimistic treatment alternative for acute proximal ruptures. The purpose of this annotation is to review the current roleof primary repair of the ACL.<...

STUDY DESIGN Six different techniques for atlantoaxial fixation were biomechanically compared in vitro by nondestructive testing. OBJECTIVE To evaluate the immediate three-dimensional stability of a new atlas claw combined with transarticular screws and alternative techniques for transarticular screw fixation in comparison with established techniques. SUMMARY OF BACKGROUND DATA Posterior tr...

Anterior cruciate ligament (ACL) reconstruction surgery has significantly evolved in recent years. This has led to development of new technologies that facilitate the diagnosis of ACL injury and the application of state of the art methods for treatment. In particular, individualized anatomical ACL reconstruction aims to restore native ACL function. Treatment is tailored to each patient based on...