Cervical Spine Injury: Tiger Attack

Abstract

Many intra-articular fracture patients eventually experience significant functional deficits, pain, and stiffness from post-traumatic osteoarthritis (PTOA). Over the last several decades, continued refinement of surgical reconstruction techniques has failed to markedly improve patient outcomes. New treatment paradigms are needed - ideally, bio/pharmaceutical. Progress in that direction has been impeded because the pathomechanical etiology of PTOA development is poorly understood. In particular, the relative roles and pathomechanisms of acute joint injury (from the initial trauma) versus chronic contact stress elevation (from residual incongruity) are unknown, primarily because there have been no objective methods for reliably quantifying either of these insult entities. Over the past decade, novel enabling technologies have been developed that provide objective biomechanical indices of injury severity and of chronic contact stress challenge to fractured joint surfaces. The severity of the initial joint injury is indexed primarily on the basis of the energy released in fracture, obtained from validated digital image analysis of CT scans. Chronic contact stress elevations are indexed by patient-specific finite element stress analysis, using models derived from post-reduction CT scans. These new measures, conceived in the laboratory, have been taken through the stage of validation, and then have been applied in studies of intra-articular fracture patients, to relate these biomechanical indices of cartilage insult to the incidence and severity of PTOA This body of work has provided a novel framework for developing and testing new approaches to forestall PTOA following intra-articular fractures.

Injurious Loading of Articular Cartilage Compromises Chondrocyte Respiratory Function

“…We have shown that explants in our model system undergoing healthy or injurious loading demonstrated no aberrant mechanical behavior indicative of structural failure over the course of any experiment. Overall axial strains after 3 hours of cyclic compression with 1.0 MPa (40-50%) were clearly elevated above estimates of in vivo strains in normal joints (10-15%) [1,2,4,22]. However, it is possible that contact stress elevations associated with unstable or incongruent joints, or normal contact stresses on degenerated cartilage lead to strain values in the range we imposed by 1.0 MPa compression in our system [22].…”

“…Epidemiologic studies have shown that individuals in occupations involving heavy repetitive loading of their joints as well as elite athletes are at increased risk for developing OA [1,2; reviewed 3,4]. Studies suggest that manipulations of key factors including surface mechanics, inflammation, or oxidative injury can alleviate different aspects of cellular injury from overloading [5,6,7].…”

Pasteurella multocida: from Zoonosis to Cellular Microbiology

“…Similar to that for bites from their smaller domestic relatives, Pasteurella infection is a high risk for bites from large cats, including lions, tigers, cougars, and others (159,162,164,166,293,(371)(372)(373)(374)(375). Cases of Pasteurella infections have also been reported for bites or exposure to mucous secretions from other wild and domestic animals, including rats, opossums, horses, and rabbits (166,259,287,295,376).…”

Unique fatality due to claw injuries in a tiger attack: A case report

“…Reported cases of attacks on humans by the tigers are very rare in the world [1][2][3][4][5][6][7]. At present, amongst the very few reported cases in the medico-legal literature, there are only three cases of fatal tiger attacks, where the victims have died due to the tiger bite injuries resulting from the known method of tiger attack [1][2][3].…”