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J F Kellam

Publications and source records attributed to J F Kellam.

At least 19 recordsLinked to original sources
PubMed2001

A prospective evaluation of the clinical utility of the lower-extremity injury-severity scores.

BACKGROUND: High-energy trauma to the lower extremity presents challenges with regard to reconstruction and rehabilitation. Failed efforts at limb salvage are associated with increased patient mortality and high hospital costs. Lower-extremity injury-severity scoring systems were developed to assist the surgical team with the initial decision to amputate or salvage a limb. The purpose of the present study was to prospectively evaluate the clinical utility of five lower-extremity injury-severity scoring systems. METHODS: Five hundred and fifty-six high-energy lower-extremity injuries were prospectively evaluated with use of five injury-severity scoring systems for lower-extremity trauma designed to assist in the decision-making process for the care of patients with such injuries. Four hundred and seven limbs remained in the salvage pathway six months after the injury. The sensitivity, specificity, and area under the receiver operating characteristic curve were calculated for the Mangled Extremity Severity Score (MESS); the Limb Salvage Index (LSI); the Predictive Salvage Index (PSI); the Nerve Injury, Ischemia, Soft-Tissue Injury, Skeletal Injury, Shock, and Age of Patient Score (NISSSA); and the Hannover Fracture Scale-97 (HFS-97) for ischemic and nonischemic limbs. The scores were analyzed in two ways: including and excluding limbs that required immediate amputation. RESULTS: The analysis did not validate the clinical utility of any of the lower-extremity injury-severity scores. The high specificity of the scores in all of the patient subgroups did confirm that low scores could be used to predict limb-salvage potential. The converse, however, was not true. The low sensitivity of the indices failed to support the validity of the scores as predictors of amputation. CONCLUSIONS: Lower-extremity injury-severity scores at or above the amputation threshold should be cautiously used by a surgeon who must decide the fate of a lower extremity with a high-energy injury.

Adolescent↗
PubMed2001

The floating shoulder: clinical and functional results.

BACKGROUND: Displaced ipsilateral fractures of the clavicle and the glenoid neck are a complex injury pattern that is usually the result of high-energy trauma. The treatment of these injuries is controversial, as good results have been reported with both operative and nonoperative treatment. METHODS: Nineteen patients who had sustained a displaced fracture of the glenoid neck with an ipsilateral clavicular fracture or acromioclavicular separation (floating shoulder) were retrospectively evaluated. The treatment was nonoperative in twelve patients and operative in seven. At the time of final follow-up, standard radiographs were made and all patients were examined by a physical therapist and either a fellowship-trained shoulder surgeon or an orthopaedic traumatologist. In addition, each patient responded to three different validated objective functional outcome measures: the Short Form-36, the American Shoulder and Elbow Surgeons Shoulder Scale, and the Disabilities of the Arm, Shoulder and Hand Questionnaire. Isokinetic strength-testing was performed, and strength in internal and external rotation was compared with that of the uninvolved shoulder. The main outcome measures included fracture-healing, functional outcome, patient satisfaction, and muscular strength. RESULTS: With regard to range of motion, only the amount of forward flexion was found to be significantly greater in the operatively treated group (p = 0.03). The operatively treated shoulders were found to be weaker in external rotation at 300 degrees /sec and weaker in internal rotation at 180 degrees /sec. When normalized to hand dominance, however, the numbers were too small to identify any significant difference. There was no significant difference between groups with regard to the three functional outcome measures. CONCLUSIONS: Good results may be seen both with and without operative treatment. Therefore, we cannot universally recommend operative treatment for a double disruption of the superior suspensory shoulder complex. Treatment must be individualized for each patient.

Adolescent↗
PubMed2000

Biomaterial developments for bone tissue engineering.

The development of bone tissue engineering is directly related to changes in materials technology. While the inclusion of materials requirements is standard in the design process of engineered bone substitutes, it is also critical to incorporate clinical requirements in order to engineer a clinically relevant device. This review presents the clinical need for bone tissue-engineered alternatives to the present materials used in bone grafting techniques, a status report on clinically available bone tissue-engineering devices, and recent advances in biomaterials research. The discussion of ongoing research includes the current state of osseoactive factors and the delivery of these factors using bioceramics and absorbable biopolymers. Suggestions are also presented as to the desirable design features that would make an engineered device clinically effective.

Biocompatible Materials↗
PubMed2000

In vivo internalization of Staphylococcus aureus by embryonic chick osteoblasts.

Staphlylococcus aureus is the primary pathogen associated with osteomyelitis, an acute and recurrent bone disease. Internalization of S. aureus by cultured embryonic chick calvarial osteoblasts has been observed. The purpose of this study was to demonstrate that internalization of bacteria by embryonic chick calvarial and tibial osteoblasts occurs in vivo. In initial experiments, 10(8) colony forming units (cfu) of S. aureus, strain UAMS-1 or Cowan 1, were injected subcutaneously under the scalp skin of 17 day chick embryos. After 45 min, calvariae were harvested and processed for transmission electron microscopy (TEM). In subsequent experiments, 10(9) cfu of UAMS-1 were injected into the allantoic sac of 17 day chick embryos via a small opening in the egg shell. After 48 h, calvariae and tibiae were harvested for TEM. S. aureus cells were found in approximately 14% of the calvarial osteoblasts after subcutaneous injection and in 11% of calvarial and tibial osteoblasts following intraallantoic injection. Endosomes were observed in some cells, but most bacteria internalized appeared to be free in the cytoplasm. Osteoblasts with as few as five bacteria had a greater loss of cytoplasmic integrity and a more heterochromatic nucleus than osteoblasts with fewer bacteria or than uninfected osteoblasts. S. aureus cells in calvariae and tibiae were also observed in the cytoplasm of approximately 4% of the osteocytes in mineralized bone matrix. Thus, internalization of S. aureus by osteoblasts in vivo augments the previous observation in vitro. This study has also shown that osteoblasts with few bacteria continue differentiating into osteocytes. Results of these experiments support the hypothesis that internalization of S. aureus by osteoblasts may play a role in the etiology of osteomyelitis.

Allantois↗
PubMed1999

Mechanisms of Staphylococcus aureus invasion of cultured osteoblasts.

Staphylococcus aureus is a bacterial pathogen causing approximately 80% of all cases of human osteomyelitis. This bacterium can adhere to and become internalized by osteoblasts and previous studies indicate that osteoblasts are active in the internalization process. In the current study, we examined the roles of microfilaments, microtubules and clathrin-dependent receptor-mediated endocytosis in the internalization of S. aureus by MC3T3-E1 mouse osteoblast cells. Microfilament and microtubule polymerization was inhibited with cytochalasin D and colchicine. Clathrin-coated pit formation was examined by using the transaminase inhibitor, monodanslycadaverine. The results of this study indicate that mouse osteoblasts utilize actin microfilaments, microtubules and clathrin-coated pits in the internalization of S. aureus; however, microfilaments seem to play the most significant role in the invasion process.

Animals↗
PubMed1999

Intraoperative fluoroscopy to evaluate fracture reduction and hardware placement during acetabular surgery.

OBJECTIVES: To evaluate use of intraoperative fluoroscopy during acetabular surgery to determine fracture reduction and accurate placement of screws. DESIGN: Retrospective. SETTING: Level I trauma center. PARTICIPANTS: Thirty patients with thirty-two acetabular fractures. INTERVENTION: Patients were evaluated with fluoroscopy during surgery to assess fracture reduction and screw placement. Anterior-posterior (AP), oblique, and lateral pelvic fluoroscopic images were obtained intraoperatively. Postoperative radiographs were used to verify fluoroscopic findings; computed tomography (CT) scans were used as the control to assess intraarticular screw placement. MAIN OUTCOME MEASUREMENTS: Radiographic and clinical assessment of fracture reduction and screw placement. RESULTS: Intraoperative fluoroscopy confirmed the extra-articular position of all screws evaluated. Postoperative CT scans confirmed the extra-articular placement of all screws assessed by fluoroscopy. Quality of reduction using intraoperative fluoroscopic images had a 100 percent correlation with reduction on final radiographs. One patient, with two screws placed without fluoroscopic evaluation, had intra-articular placement requiring revision surgery. CONCLUSIONS: Intraoperative fluoroscopy is effective in evaluating both acetabular fracture reduction and hardware placement.

Acetabulum↗
PubMed1999

Pulmonary gas exchange during intramedullary fixation of femoral shaft fractures.

BACKGROUND: This study was undertaken to determine if the alveolar dead space fraction (Vd/Vt) or the alveolar-arterial oxygen gradient (A-a DO2) increased during intramedullary fixation of femoral shaft fractures. METHODS: Fifty hemodynamically stable patients with femur fractures were prospectively enrolled. Three serial measurements of Vd/Vt and A-a DO2 were obtained immediately before femoral nailing (Pre), 30 minutes after nailing (+30), and 120 minutes after nailing (+120). Vd/Vt was determined by simultaneously measuring PaCO2 and the steady-state end-tidal CO2 (PetCO2), where Vd/Vt = (1 - PetCO2/PaCO2). RESULTS: Vd/Vt before nailing was 0.09 +/- 0.09 (mean +/- SD); at +30 and +120, Vd/Vt was 0.10 +/- 0.06 and 0.08 +/- 0.07, respectively (p > 0.2; paired t test, both time points). A-a DO2 before nailing was 84 +/- 85 mm Hg, and it did not change significantly at +30 (89 +/- 69 mm Hg; p = 0.51 vs. Pre; paired t-test) or at +120 (51 +/- 45 mm Hg). No difference in data was found with analysis by fracture classification or number of reamer passes. Vd/Vt and A-a DO2, however, were both significantly increased in patients with lung contusion (n = 6) before nailing, but neither measurement increased after nailing. One patient developed fat embolism (Vd/Vt of 0.35 at Pre and 0.31 at +120), and another patient experienced postoperative pulmonary thromboembolism (Vd/Vt increased from 0.06 at Pre to 0.17 at +120). CONCLUSION: The process of femoral nailing does not cause enough pulmonary embolization to alter pulmonary gas exchange as measured by Vd/Vt and A-a DO2. If Vd/Vt is increased preoperatively, the likelihood of subsequent pulmonary dysfunction secondary to either preoperative lung injury or fat embolism is increased.

Adult↗
PubMed1999

Pelvic ring injuries.

Major pelvic disruptions lead to significant problems in acute resuscitation and definitive management. An understanding of the injury--its assessment and treatment principles--are necessary for appropriate management by all orthopaedic surgeons. In this article, we summarize the pelvic ring session at the Southeast Fracture Symposium.

Female↗
PubMed1998

Effects of surgical approaches for acetabular fractures with associated gluteal vascular injury.

OBJECTIVES: To examine the viability of the abductor muscles following extensile exposures to the acetabulum in the presence of superior gluteal artery (SGA) or vein (SGV) injury. DESIGN: In vivo animal study. INTERVENTION: Twenty-two dogs underwent either an extensile or combined two-incision acetabular approach; either the SGA, the SGV, or no vessel was ligated. MAIN OUTCOME MEASUREMENTS: Blood flow to the affected gluteal region was evaluated by angiography, laser Doppler flowmetry, and fluorescent microspheres, and histologic and wet weight analyses were performed on the abductor muscles. RESULTS: Complete ischemic necrosis of the abductor muscles did not occur in any specimen; however, there were statistically significant reductions in immediate postoperative gluteal muscle perfusion (-47 percent, p < 0.01), loss of abductor muscle mass (-41 percent, p < 0.001), and histologic evidence of moderate to severe necrosis in five of seven specimens with extensile exposures and SGA ligation (p = 0.01). Extensile exposure and SGV ligation also caused a significant loss of muscle mass (-25 percent, p < 0.02), with moderate to severe necrosis occurring in four of seven specimens (p < 0.04). Dogs with SGA ligation undergoing the two-incision approach had no significant changes in muscle mass (-3 percent) or perfusion. Moderate to severe necrosis occurred in only one of four specimens. CONCLUSIONS: This study fails to support the hypothesis that extensile approaches to complex acetabular fractures eliminate abductor collateral circulation when performed in the presence of SGA injury.

Acetabulum↗
PubMed1998

Does bacteremia occur during high pressure lavage of contaminated wounds?

The risk of bacteremia secondary to high pressure lavage of contaminated wounds was assessed. Twenty canines were divided randomly into four treatment groups. A 10-cm incision was made over the left shoulder of each dog. The deltoideus muscle was disrupted and traumatized. Groups A and B (n = 8) had wound contamination with 1.4 x 10(9) Staphylococcus aureus followed 75 minutes later by high pressure lavage or bulb syringe irrigation, respectively. Groups C and D (n = 2) had no contamination, followed by the same treatment. Bacterial counts were obtained before and after wound irrigation. Blood cultures were obtained before, during, and 15 minutes after irrigation. Positive control cultures were obtained during injection of bacteria into the antecubital vein. A detectable bacteremia did not occur during or after high pressure lavage or bulb syringe irrigation of acute contaminated wounds but did occur in 18 of 20 positive controls. Bacterial levels were reduced by an average of 70% +/- 10% by high pressure lavage and 44% +/- 50% by bulb irrigation. Reduction of wound bacteria was achieved more consistently with high pressure lavage than with bulb syringe irrigation.

Animals↗
PubMed1997

Open pelvic fractures. A multicenter retrospective analysis.

A marked discrepancy exists in the reported mortality rates in patients with open pelvic fractures, ranging from 4.8% to 50%. A retrospective review of patients with open pelvic fractures was performed at three centers. Thirty-nine patients with open pelvic fractures were identified; the average age was 32. The average injury-severity score was 29 (13-75). There were 10 (26%) deaths. Factors that correlated with mortality and morbidity were instability of the pelvic fracture and the presence of a rectal injury. Delay in performing diverting colostomy correlated with a poor outcome. Previously described methods of treatment are still valid; however, there is a need for re-emphasis of early diverting colostomy in the patient with a rectal or perineal injury. A classification system for open pelvic fractures is proposed in this article.

Adult↗
PubMed1997

Incidence of sciatic nerve injury in operatively treated acetabular fractures without somatosensory evoked potential monitoring.

OBJECTIVE: The authors investigated the incidence of sciatic nerve injury associated with the operative repair of acetabular fractures without somatosensory evoked potential (SSEP) monitoring. DESIGN: Retrospective case review of prospectively documented pre- and postoperative physical examinations. SETTING: A level I trauma hospital. PATIENTS: All the cases were reviewed of patients with open reduction and internal fixation of acetabular fractures who underwent posterior or extensile approaches (129) performed by the three senior authors from January 1991 through March 1995. INTERVENTION: Intraoperative SSEP monitoring was not used during any of the procedures. The procedures included sixty-five Kocher-Langenbeck approaches, thirty-four combined Kocher-Langenbeck and iliofemoral approaches, four extended iliofemoral approaches, and four triradiate approaches. RESULTS: One case of iatrogenic nerve injury resulted in a sensory deficit. No patient suffered an exacerbation of a preexisting nerve injury. CONCLUSION: The results of this study indicate that open reduction and internal fixation of acetabular fractures, using current techniques with visualization and protection of the sciatic nerve, can reduce the incidence of neurologic injury to a negligible level. There does not appear to be justification for the addition of SSEP or electromyograph modalities to the operative routine of experienced surgeons.

Acetabulum↗
PubMed1997

Comparative biomechanical analysis of supracondylar femur fracture fixation: locked intramedullary nail versus 95-degree angled plate.

OBJECTIVES: To compare the initial stability of the genucephalic (GSH) intramedullary nail and the 95-degree condylar compression screw and side plate (DCS) for distal femur fractures. DESIGN: Human cadaveric biomechanical study. PARTICIPANTS: Twelve matched pairs of fresh frozen human cadaveric femurs. INTERVENTION: Genucephalic intramedullary nail device (Smith and Nephew Richards, Memphis, TN, U.S.A.) and the 95-degree DCS device (Synthes USA, Paoli, PA, U.S.A.) were compared. Grouped or dispersed screw constructs were tested for each fracture fixation system with progressively more severe simulated fracture patterns. MAIN OUTCOME MEASUREMENT: Axial and torsional stiffness values. RESULTS: The DCS plate with the dispersed screw configuration had the greatest torsional stiffness (p < 0.0011). The GSH nail with the grouped screw configuration absorbed more energy (work) during axial loading compared with the plate constructs (p < 0.0007). There were no significant differences in axial or torsional stiffness within treatment groups for fracture patterns of increasing severity. CONCLUSIONS: Based on the authors' results, the selection of a GSH nail or a DCS plate should not be determined by the severity of the fracture. If a DCS plate construct is selected, the authors recommend a dispersed screw configuration, including the most proximal hole in the plate, to provide superior stiffness in torsional loading and equal stiffness in axial loading when compared with the GSH nail constructs. If a GSH nail is selected, the authors recommend a grouped screw configuration, which absorbed more energy during axial loading compared with the DCS plate constructs and the nail with the dispersed screw configuration.

Adult↗
PubMed1995

Toxic effects of wound irrigation solutions on cultured tibiae and osteoblasts.

Irrigating wounds with solutions of antiseptic or antibiotic agents is routinely performed in orthopaedic surgery to reduce the incidence of microbial infection. The effects of these agents on healthy bone tissue is unknown. Three commonly employed antiseptic agents (hydrogen peroxide, Betadine solution, Betadine scrub) and one antibiotic solution (bacitracin) were tested on tibiae and osteoblasts isolated from embryonic chicks. Osteoblast function was evaluated by glycolytic energy metabolism (lactate production), cell number (DNA content), and collagen synthesis ([3H]proline hydroxylation). Two series of experiments were performed. To study concentration-related effects, tibiae or cells were exposed to a range of concentrations of the agents (diluted in saline, 0.9% NaCl) for 2 min, rinsed with saline, and incubated for 24 h in medium containing [3H]proline. For the recovery study, the cells were exposed to an effective, but nonlethal, concentration of the antiseptic agents for 2 min, rinsed with saline, and the incubation was continued in complete culture medium for 6, 12, 24, 48, or 72 h with [3H]proline added for the final 6 h. Solutions containing the antiseptic agents were cytotoxic to both bones and cells at concentrations well below those used clinically in irrigation solutions. In contrast, bacitracin at the concentrations tested was safe for osteoblasts and tibiae. These results suggest that the use of irrigation solutions containing H2O2, Betadine solution, or Betadine scrub on exposed bone tissue should be considered with caution.

Animals↗
PubMed1995

Open tibial diaphyseal fractures. Results of unreamed locked intramedullary nailing.

Forty-three high energy open tibial diaphyseal fractures were treated with unreamed locked intramedullary nails from 1989 to 1992, and were reviewed at a minimum of 1 year from injury. There were 6 Grade I, 2 Grade II, 16 Grade IIIA, 9 Grade IIIB, and 1 Grade IIIC open fractures. Ninety-eight percent of the fractures united in an average time of 6.1 months. However, 47% of the fractures required an additional procedure before union. Complications included 49% of fractures with malunions, 12% deep infections, 41% locking screw breakages, and 20% compartment syndromes. These results are similar to those achieved with external fixation of open tibial fractures. The unreamed locked intramedullary nail has not improved the outcome of open tibial diaphyseal fractures because the biologic consequences of the injury are of greater significance than the methods or techniques of fracture stabilization.

Adult↗