An alternative cement augmentation technique for pedicle screws is described, which was applied in two patients with mono- and bisegmental non-union after preceding multisegmental lumbar fusion. The correctly placed pedicle screws in S1 with diameters of 6 and 8.5 mm had severely enlarged the screw cavities due to segmental instability. Revision screws with 10 mm diameter demonstrated sufficien...

Abstract Correct torquing of bone screws is critical for positive patient outcomes in orthopaedic surgery. Under-or over-tightening can lead to thread stripping or screw loosening, leading implant/fixation failure and potential tissue damage disability. It has been proposed that an automated torque-limiting smart-screwdriver may be able use model-based methods determine the properties as are in...

BACKGROUND There are many techniques that are used for limb lengthening. Lengthening a limb over a plate is an alternative choice used in children or when using an intramedullary nail is difficult. OBJECTIVES In this study, we presented a new technique for tibial lengthening using a monolateral external fixator over a lengthening plate. MATERIALS AND METHODS For tibial lengthening, a monola...

Secure fixation of bone-patellar tendon-bone grafts is essential to allow early joint mobilization after anterior cruciate ligament (ACL) reconstruction surgery. This study was designed to evaluate four fixation methods of patellar tendon-bone grafts in cadaveric knees. Fifty-one fresh cadaveric patellar tendon-bone specimens were anchored in tibial or femoral metaphyseal bone tunnels. Group I ...

BACKGROUND: The use of pedicle screws is becoming increasingly popular for spinal surgery practice as the technology advances. Screw pullout due to bone quality and loading conditions is one of the most common problems observed after pedicle screw fixation. Several solutions were studied to prevent screw pullout. These can be investigated under three main categories: screw design, expandable sc...

OBJECTIVES Cement augmentation of pedicle screws could be used to improve screw stability, especially in osteoporotic vertebrae. However, little is known concerning the influence of different screw types and amount of cement applied. Therefore, the aim of this biomechanical in vitro study was to evaluate the effect of cement augmentation on the screw pull-out force in osteoporotic vertebrae, co...

This study demonstrates interfacial changes of titanium miniplate/screw with normal calvaria and nonvascularized calvarial bone graft ensued from craniectomy in a 53-year-old female. In 18 months after operation, a right parietal bone containing an L-shaped miniplate with screws, 5 mm long and 2 mm in external diameter, was harvested, fixed, and embedded in methylmetacrylate. Fifteen micrometer...

BACKGROUND Pedicle screw pullout due to poor bone quality, mainly caused by osteoporosis, is a common problem in spine surgery. Special implants and techniques, especially PMMA augmentation, were developed to improve the fixation of pedicle screws. PMMA injection into a pilot hole or through a screw involves the same risks as vertebroplasty or kyphoplasty, regardless of the technique used. Espe...

OBJECTIVE Intramedullary nailing of nonarticular proximal tibia fractures can be affected by bone density resulting in loss of stability, fixation, and malalignment in osteopenic bone. This study was designed to quantify the biomechanical effects of augmenting proximal screws with cement in intramedullary nailing of high proximal third tibial fractures. DESIGN In vitro biomechanical study usi...