ABSTRACT
Open reduction and internal fixation of fractures involves the use of metallic implants to support bone reduction. This procedure is often used in situations in which adequate alignment and stability of the bone cannot be achieved using nonsurgical methods such as casting. The locking compression plate is a contemporary implant that allows for both conventional screw placement (using nonlocking screws) and locking screw placement (where screw heads lock into the plate at a predetermined angle). This allows for greater versatility in the application of internal fixation. This article presents a general overview of locking compression plate application along with a review of the locking compression plate literature.
Subject(s)
Bone Plates , Fracture Fixation, Internal/instrumentation , Fracture Healing/physiology , HumansABSTRACT
Metallic implants are often involved in the open reduction and internal fixation of fractures. Open reduction and internal fixation is commonly used in cases of trauma when the bone cannot be healed using external methods such as casting. The locking compression plate combines the conventional screw hole, which uses non-locking screws, with a locking screw hole, which uses locking head screws. This allows for more versatility in the application of the plate. There are many factors which affect the functionality of the plate (e.g., screw placement, screw choice, length of plate, distance from bone, etc.). This paper presents a review of the literature related to the biomechanics of locking compression plates and their use as internal fixators in fracture healing. Furthermore, this paper also addresses the materials used for locking compression plates and their mechanical behavior, parameters that control the overall success, as well as inherent bone quality results.
Subject(s)
Biomechanical Phenomena/methods , Biomechanical Phenomena/trends , Fracture Fixation/instrumentation , Alloys/chemistry , Bone Plates , Bone Screws , Bone and Bones/metabolism , Equipment Design , Fracture Fixation, Internal , Fracture Healing , Humans , Internal Fixators , Stainless Steel , Titanium/chemistryABSTRACT
Disuse (i.e. inactivity) causes bone loss, and a recovery period that is 2-3 times longer than the inactive period is usually required to recover lost bone. However, black bears experience annual disuse (hibernation) and remobilization periods that are approximately equal in length, yet bears maintain or increase cortical bone material properties and whole bone mechanical properties with age. In this study, we investigated the architectural properties of bear femurs to determine whether cortical structure is preserved with age in bears. We showed that cross-sectional geometric properties increase with age, but porosity and resorption cavity density do not change with age in skeletally immature male and female bears. These findings suggest that structural properties substantially contribute to increasing whole bone strength with age in bears, particularly during skeletal maturation. Porosity was not different between skeletally immature and mature bears, and showed minimal regional variations between anatomical quadrants and radial positions that were similar in pattern and magnitude between skeletally immature and mature bears. We also found gender dimorphisms in bear cortical bone properties: females have smaller, less porous bones than males. Our results provide further support for the idea that black bears possess a biological mechanism to prevent disuse osteoporosis.