Gregory A. Zych
University of Miami
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Featured researches published by Gregory A. Zych.
Journal of Orthopaedic Trauma | 1998
James J. Hutson; Gregory A. Zych
OBJECTIVES To observe the incidence and clinical presentation of infection in periarticular fractures of the tibia and femur treated with tensioned wire external fixators. DESIGN Prospective cohort study. SETTING Level One Trauma Center in urban community. Single surgeon. PATIENTS One hundred thirty-five patients with 145 fractures: seventy tibial plateau, fifty-six pilon, and nineteen distal femur. Five-year treatment period, 1991 to 1995. MAIN OUTCOME MEASUREMENTS The incidence of infection was evaluated. RESULTS Nineteen of 145 fractures (13 percent) were complicated by infection. Infections presented as pin tract inflammation requiring intravenous antibiotics (seven), deep infection requiring debridement and removal (five), septic arthritis (three), deep fracture infection (three), and necrotizing fasciitis (one). CONCLUSIONS Infection is a common complication of juxtaarticular fractures treated with tensioned wire fixators. Excellent pin care is required. Aggressive management of infections with intravenous antibiotics and debridement will resolve infections occurring in patients treated with tensioned wire fixators. Septic arthritis is associated with wires placed less than one centimeter from the subchondral bone. Deep infection is associated with insidious swelling and excessive proliferative callus. Wire infections increase with prolonged frame time.
Clinical Orthopaedics and Related Research | 1988
Mark S. Calkins; Gregory A. Zych; Loren L. Latta; Francisco Borja; Walid Mnaymneh
Measurements of the percentage of remaining posterior acetabulum on computed tomography (CT) scan (the Acetabular Fracture Index) in posterior fracture dislocations of the hip were evaluated to determine the stability of the joint. All hips with less than 34% of the remaining posterior acetabulum were unstable. Hips with greater than 55% were stable. Between these values, hips were either stable or unstable. A statistical analysis demonstrated highly significant differences in the average remaining posterior acetabulum between the stable and unstable group. These findings were based on a review of 26 patients with posterior fracture dislocations of the hip (Epstein Type I-IV injuries) combined with CT scan analysis. The clinical status of hip stability was correlated with the Acetabular Fracture Index, and this provided the basis for the study. A simple linear measurement of the remaining posterior acetabulum on CT (the Approximate Acetabular Fracture Index) can be done easily by a physician, and this closely approximates the true remaining acetabular arc. Seven of ten unstable hips in 31 Epstein Type I-V patients showed femoral head subluxation of 0.5 mm or more on CT scan, whereas none of the 21 stable hips had demonstrable subluxation. Risk analysis provided a means of predicting hip stability for individual patients.
Journal of Orthopaedic Trauma | 2000
James J. Hutson; Gregory A. Zych
OBJECTIVE Evaluate the treatment of C3 distal femur fractures with limited internal fixation and tensioned wire circular external fixation. DESIGN Prospective cohort study, from June 1992 to July 1996. SETTING Urban Level I trauma center. PATIENTS Sixteen fractures in sixteen patients: nine male, seven female. Fractures: C3.1 one, C3.2 one, C3.3 fourteen. Twelve fractures were open: one GI, seven GII, two GIIIA, one GIIIB, and one GIIIC. INTERVENTION Fractures were treated with limited open fixation of the condylar joint surface and tensioned wire circular external fixation of the metaphysis and shaft for axial alignment. Three fractures had acute autologous bone grafts. MAIN OUTCOME MEASUREMENTS The patients extremity function was evaluated by the authors by using the Sanders et al. Distal Femur Functional Evaluation. RESULTS Sixteen of sixteen fractures healed. Two patients had delayed bone grafting for delayed union. Average frame time was twenty-five weeks. Average range of motion was 0 to 92 degrees. Five patients had less than 90 degrees of flexion. Five patients required a quadricepsplasty. Average follow-up was thirty-five months. One patient developed a pintract infection. One patient developed septic arthritis, and another developed osteomyelitis. The average Sanders et al. Function knee score was twenty-eight, with a maximum possible score of forty. CONCLUSIONS C3 fractures of the distal femur are associated with severe soft tissue injuries and bone loss. Loss of function appears to be directly related to these factors. Treatment with limited internal fixation and tensioned wire external fixation has equivalent results to other methods but has a higher incidence of infection and complications. Joint motion is retarded by binding of the soft tissues with fixation wires and pins. The technique is recommended only for salvage of severely comminuted and open fractures of the distal femur with extensive soft tissue injury. Distal femur fractures with moderate comminution and soft tissue injury should be treated with alternate methods.
Stroke | 1999
Alejandro Forteza; Sebastian Koch; Jose G. Romano; Gregory A. Zych; Iszet Campo Bustillo; Robert Duncan; Viken L. Babikian
BACKGROUND AND PURPOSE The fat embolism syndrome (FES) is characterized by the simultaneous occurrence of pulmonary and neurological symptoms as well as skin and mucosal petechiae in the setting of long-bone fractures or their surgical repair. Its pathophysiology is poorly understood, and effective treatments are lacking. We present 5 patients with long-bone fractures in whom in vivo microembolism was detected by transcranial Doppler. METHODS Five patients with long-bone fractures were monitored with transcranial Doppler for microembolic signals (MESs) after trauma. Two patients also had intraoperative monitoring. A TC-2020 instrument equipped with MES detection software was used. Detected signals were saved for subsequent review. Selected signals satisfied criteria defined previously and were categorized as large or small. RESULTS Cerebral microembolism was detected in all 5 patients and was transient, resolving within 4 days of injury. Intraoperative monitoring revealed an increase in MESs during intramedullary nail insertion. The characteristics of MESs after injury varied among patients, with large signals being more frequent in the only patient with a patent foramen ovale. CONCLUSIONS Cerebral microembolism after long-bone fractures can be detected in vivo and monitored over time. These findings may have potential diagnostic and therapeutic implications.
Journal of Orthopaedic Trauma | 2005
Jonathan C. Levy; Steven P. Kalandiak; James J. Hutson; Gregory A. Zych
Treatment of extra-articular distal humerus shaft fractures with plating techniques is often difficult, as traditional centrally located posterior plates often encroach on the olecranon fossa, limiting distal osseous fixation. The use of a modified Synthes Lateral Tibial Head Buttress Plate (Synthes, Paoli, PA) allows for a centrally placed posterior plating of the humeral shaft that angles anatomically along the lateral column to treat far distal humeral shaft fractures. Fifteen patients treated in this manner were followed to radiographic and clinical union. There were no cases of instrumentation failure orloss of reduction.
Clinical Orthopaedics and Related Research | 1995
Gregory A. Zych; James J. Hutson
A series of 20 patients with infection after intramedullary nailing of the tibia is discussed. The most common pathogen was Staphylococcus aureus, which was found in 14 patients (64%). Eleven nails were originally inserted without reaming, and 9 were reamed. Treatment protocols were based on the time of onset of infection (acute, subacute, and chronic) and the status of bone healing. In eight patients, the fractures (6) and nonunions (2) were healed at diagnosis of infection and were treated by debridement, nail removal, and antibiotics. Twelve patients had fractures (8) and nonunions (4) that were not healed. Four were treated with debridement, nail removal, and external fixation, and four with debridement and nail retention. The overall success rate for eradicating infection was 90%. Infection after unreamed nailing had fewer complications and a higher success rate for infection control than did reamed nailing. Risk factors identified in this study for infection are previous external fixation, severe open fracture, and substance abuse.
Journal of Orthopaedic Trauma | 1998
Augusto Sarmiento; Loren L. Latta; Gregory A. Zych; Patricia McKeever; Joseph P. Zagorski
OBJECTIVE To report the results from functional bracing of isolated ulnar shaft fractures. DESIGN Retrospective review. SETTING Two university hospitals. PATIENTS Isolated ulnar shaft fractures in 444 patients were stabilized in functional braces that permitted full range of motion of all joints. INTERVENTION Prefabricated braces that extended from below the elbow to above the wrist were applied within the first week after the initial injury. OUTCOME MEASURES Union of the fracture, fracture angulation, and final range of motion of the forearm were evaluated. RESULTS Two hundred eighty-seven patients were available for follow-up (65 percent). Union took place in 99 percent of the fractures. Shortening of the ulna averaged 1.1 millimeters (range 0 to 10 millimeters). Final radial angulation averaged 5 degrees (range 0 to 18 degrees). Dorsal angulation averaged 5 degrees (range 0 to 20 degrees). Average loss of pronation was greatest in fractures of the proximal third of the ulna, averaging 12 degrees. Fractures in the distal third averaged a loss of 5 degrees of pronation. CONCLUSIONS Functional bracing is a viable therapeutic alternative in the management of isolated ulnar shaft fractures. It is associated with a 99 percent union rate and good to excellent functional results in more than 96 percent of patients.
Clinical Orthopaedics and Related Research | 1987
Gregory A. Zych; Loren L. Latta; Joseph B. Zagorski
In a prospective study, from September 1980 to December 1984,146 isolated ulnar shaft fractures were treated with prefabricated fracture braces. Clinical and roentgenographic follow-up data were available for 73 fractures. Functional results were rated excellent in 64 fractures (88%), good in seven (9%), and poor in two (3%). All fractures healed in an average time of 57 days. The mean angulation measured 6° in the mediolateral plane and 4° in the anteroposterior plane. The complication rate was 18%, relating mostly to residual angulation. Most isolated fractures of the distal one-half of the ulnar shaft can be treated successfully with prefabricated fracture braces.
Journal of Orthopaedic Trauma | 2004
Howard Richter; James J. Hutson; Gregory A. Zych
The spring plate, a modified one third tubular plate, can be a viable and durable option for fixation of periarticular acetabular fractures. The use of the spring plate in acetabular fractures is demonstrated.
Circulation | 2011
Alejandro Forteza; Sebastian Koch; Iszet Campo-Bustillo; Jose Gutierrez; Diogo C. Haussen; Alejandro A. Rabinstein; Jose G. Romano; Gregory A. Zych; Robert Duncan
Background— The fat embolism syndrome is clinically characterized by dyspnea, skin petechiae, and neurological dysfunction. It is associated mainly with long bone fracture and bone marrow fat passage to the systemic circulation. An intracardiac right-to-left shunt (RLS) could allow larger fat particles to reach the systemic circulation. Transcranial Doppler can be a useful tool to detect both RLS and the fat particles reaching the brain. Methods and Results— We prospectively studied patients with femur shaft fracture with RLS evaluation, daily transcranial Doppler with embolus detection studies, and neurological examinations to evaluate the relation of RLS and microembolic signals to the development of fat embolism syndrome. Forty-two patients were included; 14 had an RLS detected. Seven patients developed neurological symptoms; all of them had a positive RLS (P=<0.001). The patients with an RLS showed higher counts and higher intensities of microembolic signals (P=<0.05 and P=<0.01, respectively) compared with those who did not have an RLS identified. The presence of high microembolic signal counts and intensities in patients with RLS was strongly predictive of the occurrence of neurological symptoms (odds ratio, 204; 95% confidence interval, 11 to 3724; P<0.001) with a positive predictive value of 86% and negative predictive value of 97%. Conclusions— In patients with long bone fractures, the presence of an RLS is associated with larger and more frequent microembolic signals to the brain detected by transcranial Doppler study and can predict the development of neurological symptoms.