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...

Distal femur fractures routinely heal by secondary bone healing, which relies on interfragmentary motion. Periarticular locking plates are commonly used for fixation in distal femur fractures but are associated with a high nonunion rate, likely due to the stiffness of the constructs. Far cortical locking (FCL) screws are designed to allow micromotion at the near cortex while maintaining purchas...

OBJECTIVE To investigate microbiological biofilm contamination of retrieved bone-anchored hearing aids. MATERIALS AND METHODS Nine failed, retrieved bone-anchored hearing aids and 16 internal screws were examined by scanning electron microscopy. A fixture from a failing implant, which had been removed and disassembled under aseptic conditions, was cultured. Finally, an internal screw from a n...

Slotted and cruciate auxiliary screw head design modifications for "salvaging" a stripped hexagonal head screw were studied. Thirty screws were divided into 3 groups: Group 1 = control without modification, Group 2 = auxiliary cruciate design modification and Group 3 = auxiliary slot design modification. Screws were inserted into adhesive filled high-density synthetic bone tunnels using a hexag...

OBJECTIVES Screw fixation and fragment anchoring in osteoporotic bones is often difficult. Problems like the cut out phenomenon and implant migration in osteoporotic bones have been reported. One possibility of improving the anchoring force of screws is augmentation of the screw. Cement-augmented screws in spinal surgery could exhibit a better anchoring in osteoporotic bones. METHODS The purp...

Abstract Background Superior biomechanical performance of tapered interference screws, compared with non-tapered reference to the anterior cruciate ligament (ACL) reconstruction process, has been reported in literature. However, effect screw’s body slope on initial stability ACL is poorly understood. Thus, main goal this study was investigate reconstructed ACL. Methods Based best screw-bone tun...

Osteoporosis causes a decrease in bone mineral density. To overcome the decrease in fixation strength, a variety of techniques and devices have been developed, including cement augmentation of pedicle screws. Polymethyl methacrylate (PMMA), is commonly known as bone cement, and is widely used for implant fixation in various orthopaedic and spine surgery. In general, PMMA augmentation of pedicle...

Inserting a screw into a long bone introduces a stress riser that can predispose the bone to fracture. Where multiple screws are inserted this vulnerability may be increased. It is thought that the pattern of screw insertion plays an important part in determining the susceptibility of the bone to stress fracture. In order to study the importance of pattern of screw insertion, third generation c...

Horizontal bone augmentation of the maxillary and mandibular alveolar ridges has been conventionally performed using mini titanium alloy screws. The titanium alloy screws are used to fixate corticocancellous block grafts to the recipient site or for tenting the mucoperiosteum to retain particulate bone grafts. Nonresorbable guided tissue regenerative membranes reinforced with titanium have also...

1 Takashi Nuri, MD, PhD Koichi Ueda, MD, PhD Masashi Okada, MD, PhD Yuki Otsuki, MD Hiroyuki Iwanaga, MD Department of Plastic and Reconstructive Surgery Osaka Medical College Takatsuki, Osaka, Japan Sir, A lthough the osteocutaneous free flap is the best choice for mandibular reconstruction, it cannot be chosen sometimes because of the patient’s condition. Then, a metal reconstruction plate is...