[Show abstract][Hide abstract] ABSTRACT: Orthogonal and parallel plate constructs are used for fixation of intra-articular distal humerus fractures but optimal plate configuration remains controversial. The purpose of this study was to compare the biomechanical properties of orthogonal versus parallel plate constructs in a cadaver distal humerus fracture model.
An intra-articular distal humerus fracture with a metaphyseal defect was created in 14 matched pairs of cadaver elbows. Paired specimens were fixed with either orthogonal or parallel plates from a single elbow plating system using nonlocking screws. Using a novel testing protocol, loading was applied to the forearm and was transmitted to the distal humerus through intact collateral ligaments, olecranon, and radial head. Seven matched pairs were tested under varus loading and seven under axial/sagittal loading. Each specimen underwent cyclic loading first, followed by loading to failure.
Parallel plate constructs had significantly higher stiffness than orthogonal ones during cyclic varus loading (P = .002). Screw loosening occurred in all posterior plates of orthogonal constructs but in no plates of parallel constructs (P = .001). Parallel constructs had significantly higher ultimate torque in varus loading to failure (20.7 vs 15.9 Nm, P = .008), and higher ultimate load in axial/sagittal loading to failure (1287.8 vs 800.0 N, P = .03).
Parallel plating of intra-articular distal humerus fractures with a metaphyseal defect demonstrates superior biomechanical properties compared to orthogonal plating, and may be preferable for fixation of these fractures.
Journal of shoulder and elbow surgery / American Shoulder and Elbow Surgeons ... [et al.] 01/2011; 20(1):12-20. DOI:10.1016/j.jse.2010.08.005 · 2.37 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Satisfactory outcome of intraarticular distal humerus fractures depends on anatomic joint restoration and stable fracture fixation to allow early motion. Orthogonal constructs (medial plate on medial column and posterior plate on lateral column) and parallel constructs (medial plate on medial column and lateral plate on lateral column) have been proposed for fixation of these fractures. However, the optimal configuration remains controversial. There are no clinical studies comparing these constructs and existing biomechanical studies had methodological limitations and reported conflicting results.
ASME 2009 4th Frontiers in Biomedical Devices Conference; 01/2009
[Show abstract][Hide abstract] ABSTRACT: New antibiotics have been developed targeting resistant microorganisms; however, limited information is available on their use in implant-related chronic osteomyelitis. We evaluated the infection control rate of linezolid in treating these challenging infections and delineate indications for its use. We retrospectively reviewed 22 consecutive adult patients with chronic implant-related osteomyelitis, treated with linezolid in addition to surgical débridement and implant removal. Osteomyelitis was associated with fracture fixation implants (n = 18) or arthroplasty implants (n = 4). Methicillin-resistant Staphylococcus aureus (MRSA) was the most common pathogen (10 of 22 patients). Fourteen patients had one or more comorbidity, including intravenous drug abuse in four patients. Indications for linezolid use included preference for oral administration in 13 patients, presence of vancomycin-resistant enterococcus (VRE) in five patients, and development of allergic reactions to vancomycin in four patients. Fourteen patients were followed for a minimum of 6 months (mean, 22 months; range, 6-34 months) with no recurrence of infection. Linezolid is a reasonable alternative for treating chronic implant-related osteomyelitis. Our treatment protocol, including linezolid, achieved control of infection in all patients despite the challenging nature of these infections due to patient comorbidities and resistant organisms.
Clinical Orthopaedics and Related Research 09/2007; 461(461):40-3. DOI:10.1097/BLO.0b013e3180986d60 · 2.88 Impact Factor