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J R Chapman

Publications and source records attributed to J R Chapman.

At least 37 records · Page 2Linked to original sources
PubMed2000

Type II odontoid fractures in the elderly: early failure of nonsurgical treatment.

The optimum treatment of Type II odontoid fractures in the geriatric population remains controversial. Coexisting medical conditions encountered in the elderly patient often increase operative risk and make cervical immobilization difficult to tolerate. Previous studies have shown increased morbidity and mortality and decreased fusion rates for Type II odontoid fractures treated with cervical orthoses in the geriatric population, whereas low morbidity and mortality rates with operative management have recently been documented. To investigate the role of surgical and nonsurgical treatment, a retrospective analysis was performed of patients with Type II odontoid fractures who were at least 65 years old and were consecutively admitted to a single medical center from 1994 to 1998. Twenty patients met inclusion criteria. In 12 patients nonsurgical management with a cervical orthosis was attempted. The nonsurgical management failed early in six patients, with one associated death. Eleven patients were treated surgically with either anterior odontoid screw fixation or posterior C1-2 transarticular screw fixation and modified Gallie fusion. Postoperatively one patient required revision of the C1-2 transarticular screws, and there was one death. In conclusion Type II odontoid fractures in this elderly population were associated with early 10% morbidity and 20% mortality rates. Nonsurgical management of Type II odontoid fractures failed early in six (50%) of 12 patients, whereas surgical treatment failed early in one of 11 (9%) patients. Both the nonsurgical and surgical treatments resulted in approximately 10% morbidity and 10% mortality rates.

Aged↗
PubMed2000

Posttransplant cataract: lessons from kidney-pancreas transplantation.

INTRODUCTION: Cataract is a major cause of visual disturbance after transplantation. Although corticosteroid therapy has been linked with posterior subcapsular cataract, its natural history in the cyclosporine era is not well understood. METHODS: Baseline and regular postoperative slit-lamp biomicroscopy and ophthalmic examinations (n=432) were performed in 108 eyes of simultaneous kidney/pancreas (SPK) recipients (n=54) for up to 10 years after transplantation. Triple therapy immunosuppression of cyclosporine, azathioprine, and prednisolone was used. RESULTS: Cataract was present in 40% of eyes at simultaneous kidney/pancreas associated with duration of diabetes, lower insulin dose, and the use of pretransplant hemodialysis (P<0.05-0.01). Cataract became increasing more common 2 years after simultaneous kidney/pancreas, and lens abnormalities were virtually universal at 6-10 years by slit lamp biomicrosopy. The instantaneous hazard rate for new cataract formation was highest within the first 2 years and remained abnormal for the study duration. Nuclear and posterior subcapsular cataract increased significantly after transplantation (P<0.05) and were the predominant types of cataract presenting late. Risk factors for posttransplant cataract formation included older age and high-dose pulse methylprednisolone dose. Visual acuity was reduced by severity of cataract grade, presence of combined nuclear and subcapsular cataract, retinal hemorrhage and underlying diabetic retinopathy (P<0.05-0.001). Cataract formation imposed significant additional impairment of visual acuity above that of diabetic retinopathy. Cataract surgery was undertaken in 14% of eyes, improving visual acuity from mean decimalized score of 0.28 to 0.43, P<0.01 but did not normalize it to the noncataract level of 0.72. CONCLUSION: Transplantation substantially increases all types of cataract, and is highly prevalent by slit lamp examination. High-risk patients are older and diabetic, and received hemodialysis and pulse corticosteroid therapy. In contrast to older studies using high-dose corticosteroid and azathioprine, the pattern of cataract in the cyclosporine era is different with broader cataract types, a weaker association with corticosteroids and a progressive course. Regular screening of visual acuity and appropriate surgery for posterior subcapsular or severe cataract are recommended.

Adult↗
PubMed2000

Progression of macrovascular disease after transplantation.

INTRODUCTION: Cardiovascular and cerebrovascular disease are major causes of morbidity and mortality after kidney transplantation. The aim of this longitudinal study was to examine the natural history of carotid plaque and to determine risk factors for the progression of vascular disease in uremic, type 1 diabetic patients who received a combined kidney and pancreas transplant. METHODS: Carotid artery (n=765) and lower limb vascular duplex scanning (n=656) were prospectively undertaken in 82 recipients before transplantation, at 6 months, and then at annual intervals for up to 10 years. Plaque in the internal carotid artery (ICA), external carotid artery, and common carotid artery was classified by type, location, extent, and degree of functional obstruction, and evaluated using multivariate analysis. RESULTS: Carotid plaque was present in 22.5% of patients at initial scanning, but increased to 56.6% by 7-10 years after transplantation, especially in the ICA and common carotid artery. Both the severity and extent of plaque increased, and plaque became more complex and heterogeneous with time after transplantation (P<0.001). Carotid plaque was associated with older age, current cigarette smoking, hyperphosphatemia, hypoalbuminemia, duration of pretransplantation dialysis, and presence of lower limb plaque (P<0.05-0.001). The severity of carotid plaque increased in older, hypertensive recipients and was associated with metabolic acidosis and hyperphosphatemia (all P<0.05). Severity of ICA disease correlated with disease in the contralateral ICA (r=0.57, P<0.001) and femoral arteries (r=0.42, P<0.001). Paradoxically, each carotid artery progressed independently of the other. ICA disease severity progressed when heterogenous, calcified, or new plaque was present on scanning, and with reduced renal transplant function (P<0.01-0.001). The mean ICA blood flow remained stable with time but was progressively impaired by hypertension, fasting hyperglycemia, and a lower prednisolone dose (P<0.05). Cerebrovascular events occurred in only four patients and were unrelated to carotid disease, implying relative plaque stability. CONCLUSION: Extensive carotid vascular wall abnormalities increased significantly despite kidney and pancreas transplantation. Initiation of plaque was associated with systemic factors, whereas progression of established plaque was largely influenced by local factors within the arterial wall.

Adult↗
PubMed2000

The anterior T-frame external fixator for high-energy proximal tibial fractures.

The authors' experience using anterior T-frame external fixation combined with percutaneous internal fixation for treatment of high-energy proximal tibial fractures is reported. Thirty-six patients (38 fractures) were reviewed who were treated during a consecutive 42-month period. Three patients died and one patient had an amputation for a Type IIIC open injury, leaving 20 males and 12 females with 21 closed and 13 open fractures (two Type II, seven Type IIIA, three Type IIIB, and one Type IIIC). The average followup was 26 months. Fractures united at a mean of 20 weeks. Ten secondary surgical procedures were planned, including seven antibiotic bead removals with autogenous bone grafting and three soft tissue coverage procedures. Nine (26%) complications were found, including one deep infection (septic arthritis) and three pin tract infections, and one each malunion, nonunion, refracture, knee stiffness requiring manipulation under anesthesia, and deep venous thrombosis. The average Knee Society score was 85 for pain and 83 for function. All patients achieved full knee extension and mean flexion was 125 degrees. The anterior T-frame external fixator with percutaneous internal fixation is a reliable method to stabilize these injuries. It is simple, inexpensive, and effective.

Adolescent↗
PubMed2000

Use of structural allografts in spinal osteomyelitis: a review of 47 cases.

OBJECT: The use of structural allografts in spinal osteomyelitis remains controversial because of the perceived risk of persistent infection related to a devitalized graft and spinal hardware. The authors have identified 47 patients over the last 3.5 years who underwent a surgical decompression and stabilization procedure in which fresh-frozen allografts were used after aggressive removal of infected and devitalized tissue. The patients subsequently underwent 6 weeks of postoperative antibiotic therapy (12 months for those with tuberculosis [TB]). METHODS: Follow-up data included results of serial clinical examinations, radiography, laboratory analysis (erythrocyte sedimentation rate and white blood cell count), and clinical outcome questionnaires. Of the original 47 patients (14 women and 33 men, aged 14-83 years), 39 were available for follow up. The average follow-up period at the time this article was submitted was 17 +/- 9 months (median 14 months, range 6-45 months). In the majority of cases (57%), a Staphylococcus species was the infectious organism. Predisposing risk factors included intravenous drug abuse (IVDA), previous surgery, diabetes, TB, and concurrent infections. During the follow-up period only two patients suffered recurrent infection at a contiguous level; both had a history of IVDA and one also had a chronic excoriating skin condition. No other recurrent infections have been identified, and no patient has required reoperation for persistent infection or allograft/hardware failure. CONCLUSIONS: It is the authors' opinion that the use of structural allografts in combination with aggressive tissue debridement and adjuvant antibiotic therapy provide a safe and effective therapy in cases of spinal osteomyelitis requiring surgery.

Adolescent↗
PubMed1999

Predictors of renal transplant histology at three months.

BACKGROUND: The quality of a damaged kidney, the complexity of the surgery, and the events in the first weeks after transplantation, such as delayed graft function (DGF) and acute rejection, may influence its histological appearance and long-term survival. The aim of this study was to evaluate the importance of these factors in predicting renal allograft histology at 3 months. METHODS: Prospective, protocol kidney biopsy specimens (n=112), obtained 3 months after transplantation, were scored for chronic damage by the Banff schema and evaluated by multivariate analysis against donor factors, implantation histology, prior recipient sensitization, ischemia, perioperative factors, and subsequent clinical events, such as DGF and acute rejection. RESULTS: Adequate samples were obtained in 102 of 112 biopsies and classified as chronic Banff grade 0 (n=22), grade I (n=56), grade II (n=23), or grade III (n=1). Acute Banff scores were minimal. DGF occurred in 49% and was the strongest predictor of tubulointerstitial damage at 3 months. DGF correlated with acute tubular necrosis on the implantation biopsy specimen and with the number of acute rejection episodes; DGF also correlated with the Banff grades of chronic glomerulitis, chronic interstitial fibrosis, and tubular atrophy scores (P<0.05-0.001) in the 3-month biopsy specimen. By multivariate analysis, chronic tubular atrophy was independently predicted by the presence of vascular disease in the donor biopsy specimen, DGF, and vascular rejection occurring within the first 3 months (P<0.05-0.001). Chronic interstitial fibrosis was unrelated to fibrosis in the donor biopsy specimen but was independently predicted by DGF, donor age, and vascular rejection (P<0.05-0.001). Vascular disease in the donor biopsy specimen correlated with chronic intimal thickening (r=0.36, P<0.01) and arteriolar hyalinosis score (r=0.54, P<0.001) on the 3-month biopsy specimen. Banff chronic intimal vascular thickening was independently predicted by donor biopsy specimen vascular grade, prior vascular rejection episodes, and renal cold ischemia time (P<0.05-0.01). There were no correlates with the mean cyclosporine (CsA) dose, blood levels, diagnosis of CsA toxicity, or cellular rejection within the first 3 months. CONCLUSIONS: This study has demonstrated that the quality of the donor organ at implantation was strongly predictive of subsequent renal histology in grafts functioning at 3 months. Vascular rejection and DGF had a significant long-term effect on graft damage, but cellular rejection and simple measures of CsA exposure did not.

Acute Disease↗
PubMed1999

Successful obstetric outcome after simultaneous pancreas and kidney transplantation.

A 34-year-old woman became pregnant two years after having a simultaneous pancreas and kidney (SPK) transplantation, necessitated by type 1 diabetes and end-stage renal disease. The pregnancy was uneventful until 30 weeks' gestation, when she developed pancreatitis and a worsening of mild hypertension. A healthy 1700 g boy was delivered by caesarean section at 34 weeks' gestation. This is the first report of a successful pregnancy after SPK transplantation in Australia.

Adult↗
PubMed1999

Mercaptoacetyltriglycine diuretic renography and output efficiency measurement in renal transplant patients.

Suspected urinary tract obstruction following renal transplantation presents a diagnostic dilemma. The purposes of this study were: (1) to establish a normal range of measurement of output efficiency (OE) in the renal transplant population, and (2) to assess prospectively the usefulness of OE in the setting of allograft obstruction. Twenty-two renal transplant patients with stable renal function and no evidence of hydronephrosis on serial ultrasound examination had a diuretic mercaptoacetyltriglycine scan with calculation of OE. Three renal transplant patients with confirmed graft obstruction were also studied. Standard qualitative and quantitative parameters as well as OE were calculated. The mean OE for the 22 normal renal transplant patients was 86.3%+/-3.7% (range: 77%-91%). OE values in the three obstructed patients were 59%, 68% and 75% respectively. It is concluded that OE should normally exceed 77% in renal graft recipients. OE is a promising means of diagnosing functional obstruction in these patients.

Adult↗
PubMed1999

Diabetic retinopathy after combined kidney-pancreas transplantation.

Diabetic retinopathy (DR) is amenable to good diabetic control; however, only successful pancreas transplantation can achieve sustained normoglycaemia. The aim of this long-term study was to examine the course of DR in insulin-dependent diabetic recipients of a simultaneous kidney and pancreas transplant (SPK). Successful SPK recipients (n = 46) and failed pancreas transplant with a functioning kidney transplant (n = 8) were assessed by baseline and regular post-transplant ophthalmic examinations (n = 432) for up to 10 yr after SPK. At the time of SPK (n = 108 eyes), the mean duration of diabetes was 25 +/- 7 yr, ten eyes were blind, and 79% of eyes had advanced DR that had panretinal laser (panretinal photocoagulation, PRP. Successful SPK recipients had normal glucose control with a mean HBA1C of 5.2 +/- 0.6%. DR remained stable in 75% of both the study and control groups, with no difference between groups. The DR mostly evolved towards inactive proliferative DR. After SPK, 14% of non-blind eyes showed improvement of DR, 76% remained stable and 10% progressed. Early vitreous haemorrhage occurred in 6.1% of eyes, and was related to established DR. Cataract of all types increased after transplantation (p < 0.01), which reduced visual acuity (VA) in affected eyes. The mean overall VA remained unchanged for the study duration. In summary, uremic patients from diabetic nephropathy had a high prevalence of severe proliferative DR and blindness at the time of presentation for SPK. This was subsequently stabilised to inactive proliferative DR by appropriate laser therapy followed by metabolic control achieved by SPK.

Cataract↗
PubMed1999

Low-dose dopamine after kidney transplantation: assessment by Doppler ultrasound.

Low-dose dopamine (LDD) is commonly used after kidney transplantation as a renoprotective agent, although the benefits of dopamine (DA) in this setting are controversial. LDD increases renal blood flow, decreases resistive index (RI) and causes diuresis in normal kidneys. We hypothesised that the vasculature of a denervated renal transplant may not respond to DA in the same way as healthy native kidneys. In a prospective, controlled study, renal blood flow velocity and vascular resistance were measured by Doppler ultrasound in recent kidney transplants (n = 20) over a range of DA doses (0-5 microg/kg/min). Main renal artery velocity was lower in kidneys with acute renal dysfunction than in those with normal function (0.60 +/- 0.31 vs. 0.81 +/- 0.24, respectively, p < 0.05). There was no demonstrable haemodynamic effect of LDD on either RI or main renal artery velocity as measured by Doppler ultrasound. Interestingly, the only significant correlation with mean RI was trough cyclosporin A level (r = 0.57, p < 0.001). Technical or timing factors cannot be used to explain the absence of DA effect, with equivalent doses capable of producing vasodilatation and reduced RI in studies of normal kidneys. In summary, these findings contrast the DA response of healthy native kidneys and may explain studies showing no clinical benefit of LDD in the early post-transplant period. These data suggest an insensitivity of recently implanted kidneys to the vasodilatory effects of LDD, that other factors such as cyclosporin A vasoconstriction may also be important, and question the rationale for routine LDD after kidney transplantation.

Adult↗
PubMed1999

Occult vertebral fractures in ankylosing spondylitis.

STUDY DESIGN: A retrospective review of patients with ankylosing spondylitis involved in a blunt trauma. SETTING: Patients referred to two Level I tra uma centers. OBJECTIVES: To determine the incidence and clinical sequelae in thi s patient population where vertebral injury was diagnosed on a delayed basis. SUMMARY OF BACKGROUND DATA: The ankylosed spine is at increased risk for fracture and spinal cord injury. Radiological identification of injury is more difficult than in the normal spine. RESULTS: Over a 5 year period, 21 patients were identified with seven having an occult vertebral fracture not recognized as the primary injury or occurring as a second non-contiguous injury level. In these cases, delay in diagnosis of the occult injury was from 3 to 22 days. Development of secondary neurological deficits occurred in three patients. CONCLUSIONS: A high index of suspicion and an appreciation of the extreme instability of a fracture in ankylosing spondylitis must be present.

Accidental Falls↗
PubMed1999

Brefeldin A-induced apoptosis in prostatic cancer DU-145 cells: a possible p53-independent death pathway.

OBJECTIVE: To investigate the growth inhibitory mechanism of brefeldin A (BFA), an antiviral antibiotic, in androgen-independent prostatic cancer DU-145 cells. MATERIALS AND METHODS: The inhibitory effects of BFA (30 ng/mL) on cell growth were monitored by cell counting and viability tests after specified exposures. Flow cytometry and western immunoblot analysis were performed to examine the effects of BFA on the cell cycle and on specific growth regulators. The possible induction of apoptosis by BFA was further assessed by in situ hybridization (ISH) assay and by qualitative DNA analysis using agarose-gel electrophoresis. RESULTS: Cell growth was completely inhibited with BFA (30 ng/mL), accompanied by 40-50% cell death. Cell cycle analysis revealed that this growth inhibition coincided with an 85% reduction in the S-phase cell population. Western blots showed that the expression of cell cycle-dependent kinases (cdk2 and cdk4), cyclin D1 and p53 was significantly reduced, while WAF1 was increased, after BFA treatment. Apoptosis was confirmed by both the ISH assay, which showed the characteristic brownish staining of BFA-treated cells, and by DNA analysis, which revealed the internucleosomal DNA ladder. CONCLUSION: BFA-induced growth inhibition in DU-145 cells is primarily due to the modulation of specific G1 cell-cycle regulators, blocking the G1-S phase progression. Such a growth arrest ultimately results in apoptosis, presumably through a p53-independent pathway.

Antiviral Agents↗
PubMed1999

Early versus delayed surgery for acute cervical spinal cord injury.

The optimal timing of surgical intervention in cervical spinal cord injuries has not been defined. The goals of the study were to investigate changes in neurologic status, length of hospitalization, and acute complications associated with surgery within 3 days of injury versus surgery more than 3 days after the injury. All patients undergoing surgical treatment for an acute cervical spinal injury with neurologic deficit at two institutions between March 1989 and May 1991 were reviewed retrospectively. Forty-three patients initially were evaluated. At one institution, patients with neurologic spinal injuries had surgical intervention within 72 hours of injury. At the other institution, patients underwent immediate closed reduction with subsequent observation of neurologic status for 10 to 14 days before undergoing surgical stabilization. This study indicates that patients who sustain acute traumatic injuries of the cervical spine with associated neurologic deficit may benefit from surgical decompression and stabilization within 72 hours of injury. Surgery within 72 hours of injury in patients sustaining acute cervical spinal injuries with neurologic involvement is not associated with a higher complication rate. Early surgery may improve neurologic recovery and decrease hospitalization time in patients with cervical spinal cord injuries.

Adolescent↗
PubMed1999

Risk of early closed reduction in cervical spine subluxation injuries.

OBJECT: The authors retrospectively reviewed 121 patients with traumatic cervical spine injuries to determine the risk of neurological deterioration following early closed reduction. METHODS: After excluding minor fractures and injuries without subluxation, the medical records and imaging studies (computerized tomography and magnetic resonance [MR] images) of 82 patients with bilateral and unilateral locked facet dislocations, burst fractures, extension injuries, or miscellaneous cervical fractures with subluxation were reviewed. Disc injury was defined on MR imaging as the presence of herniation or disruption: a herniation was described as deforming the thecal sac or nerve roots, and a disruption was defined as a disc with high T2-weighted signal characteristics in a widened disc space. Fifty-eight percent of patients presented with complete or incomplete spinal cord injuries. Thirteen percent of patients presented with a cervical radiculopathy, 22% were intact, and 9% had only transient neurological deficits in the field. Early, rapid closed reduction, using serial plain radiographs or fluoroscopy and Gardner-Wells craniocervical traction, was achieved in 97.6% of patients. In two patients (2.4%) closed reduction failed and they underwent emergency open surgical reduction. The average time to achieve closed reduction was 2.1+/-0.24 hours (standard error of the mean). The incidence of disc herniation and disruption in the 80 patients who underwent postreduction MR imaging was 22% and 24%, respectively. However, the presence of disc herniation or disruption did not affect the degree of neurological recovery, as measured by American Spinal Injury Association motor score and the Frankel scale following early closed reduction. Only one (1.3%) of 80 patients deteriorated, but that occurred more than 6 hours following closed reduction. CONCLUSIONS: Although disc herniation and disruption can occur following all types of traumatic cervical fracture subluxations, the incidence of neurological deterioration following closed reduction in these patients is rare. The authors recommend early closed reduction in patients presenting with significant motor deficits without prior MR imaging.

Cervical Vertebrae↗
PubMed1999

Anterior cortical allograft in thoracolumbar fractures.

A prospective cohort study of consecutive patients with thoracolumbar fractures from two centers was conducted to evaluate the use of cortical allograft for anterior spine reconstruction. The purpose was to determine whether allograft bone had deleterious effects on fusion rates and maintenance of correction. Thirty-six patients were followed for a minimum of 2 years. A radiologic fusion rate of 81% was found, and there was a loss of postoperative correction in eight patients. The addition of posterior instrumentation was not significantly different from anterior surgery alone with respect to union rates but did provide a more reliable maintenance of correction of deformity. There were no cases of disease transmission. The authors conclude that cortical allograft for anterior spine reconstruction in trauma is safe and despite having a fusion rate lower than autogenous iliac crest, little clinical significance is attributable to the radiologic appearance of nonunion at the host-allograft junctions.

Adult↗
PubMed1998

Treatment of type II, IIIA, and IIIB open fractures of the tibial shaft: a prospective comparison of unreamed interlocking intramedullary nails and half-pin external fixators.

OBJECTIVE: To compare unreamed intramedullary nailing (IMN) with external fixation (EF) in patients with Type II, IIIA, and IIIB open fractures of the tibial shaft. DESIGN: An inception cohort of consecutive patients with Type II, IIIA, and IIIB tibial fractures incurred between January 1988 and March 1993 were systematically allocated into one of two treatment groups. Patients were treated and followed with a prospectively designed protocol. PATIENTS AND SETTING: All patients were skeletally mature and had incurred a fracture of the tibial diaphysis within twenty-four hours of presentation to the tertiary care hospital, a Level I Trauma Center. One hundred seventy-four fractures in 168 patients were stabilized with either IMN (104) or half-pin EF (70). There were 132 men and thirty-six women, with an average age of thirty-three years (range, 14 to 77 years). INTERVENTION: Except for the selection of the fixation device, open fracture care was similar in the two treatment groups. All patients underwent emergent irrigation and debridement with concomitant skeletal stabilization. Cephalosporin antibiotics were administered perioperatively for twenty-four to forty-eight hours. No wounds were closed primarily. Delayed primary closure, skin grafting, and/or myoplasty were performed between three and ten days after injury. MAIN OUTCOME MEASURES: The main outcome measures were final fracture alignment, presence of infection or inflammation, hardware failure, time to union, and the number of operative procedures. RESULTS: The IMN group had significantly fewer incidences of malalignment than did the EF group [8 vs. 31 percent; p = 0.00005; confidence interval (CI) = 0.18, 0.76] and had significantly fewer subsequent procedures (mean of 1.7 vs. mean of 2.7 per fracture; p = 0.001; CI = 0.45, 1.59). IMN resulted in fewer infections/ inflammatory problems than did EF at the injury site (13 vs. 21 percent; p = 0.73; CI = -0.63, 0.45) and significantly fewer at surgical interfaces (i.e., pin sites, nail and interlocking screw insertion sites; 2 vs. 50 percent; p = 0.000; CI = 0.39, 0.60). No significant difference was found in the healing rates for the two implant groups. The more severe Gustilo injury types had longer healing times regardless of the type of fixation. CONCLUSIONS: Results suggest that unreamed interlocking intramedullary nails are more efficacious than half-pin external fixators, in particular with regard to maintenance of limb alignment. However, the severity of soft tissue injury rather than the choice of implant appears to be the predominant factor influencing rapidity of bone healing and rate of injury site infection.

Adolescent↗