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Pavlos Katonis

Publications and source records attributed to Pavlos Katonis.

17 recordsLinked to original sources
PubMed2007

Postoperative infections of the thoracic and lumbar spine: a review of 18 cases.

We retrospectively reviewed 18 consecutive patients (age range, 19-81 years; average age, 55 years) with postoperative infections of the spine. Postdiscectomy-laminectomy infections confined to the disc space (n = 2) were treated with percutaneous transpedicle drainage. Open débridement was performed in patients with an epidural or paraspinal abscess (n = 3). Infections after posterior instrumentation that manifested during the first postoperative month were treated with single (n = 3) or multiple débridements and delayed closure (n = 7), with preservation of instrumentation. Infections that presented more than 9 months after the initial operation (n = 3) were treated with open débridement and removal of instrumentation. The minimum followup was 1 year (mean 2 years, range, 1-4 years). Infections in 17 of the 18 patients resolved effectively and one patient with metastatic cancer died of sepsis. Transpedicle drainage resulted in immediate relief of back pain. Instrumentation can be retained safely in patients with infections that manifest during the first month after implantation. Single surgical débridement is effective in selected cases. After repeated débridements, the presence of healthy granulation tissue in the wound and decreasing C-reactive protein activity were associated with safe and effective wound closure. Despite radiographic evidence of hardware loosening in infections manifested more than 9 months after implantation, we removed hardware without destabilizing the spine.

Adult↗
PubMed2006

Surgical treatment of spinal brucellosis.

UNLABELLED: We retrospectively reviewed 10 patients with spinal brucellosis of the thoracic and lumbar spine who were treated successfully with a combination of surgery and antibiotics. All patients had back pain; six patients had radiculopathy and one patient had paraparesis. Patients with spondylodiscitis without epidural abscesses (n = 3) had transpedicle discectomy and drainage. Epidural abscesses in the lumbar area caused by spondylodiscitis (n = 3), spondylitis (n = 2), and discitis with infected disc herniation (n = 1), were drained using a posterior approach combined with posterolateral fusion in two patients with spondylodiscitis and discectomy in the patient with a herniated disc. One patient presented with a pathologic fracture and neural compression and was treated with anterior corpectomy and reconstruction. Antibiotic treatment was given for 3 to 9 months. Mean followup was 3 years. Back pain improved soon after surgery. Recovery from radiculopathy and paraparesis was complete. One patient had recurrence of infection 9 months after initial treatment. Clinical manifestation of spinal brucellosis can include spondylitis, spondylodiscitis, discitis, epidural abscess, paraspinal abscess, and vertebral collapse. Transpedicle drainage allows tissue diagnosis and facilitates treatment. Because brucellosis usually responds to antibiotics, surgery is considered as the last resort in treating spinal brucellosis, but severe neurologic deficit and incapacitating back pain often necessitate surgical intervention. LEVEL OF EVIDENCE: Therapeutic study, level IV (case series). Please see the Guidelines for Authors for a complete description of levels of evidence.

Adult↗
PubMed2005

Does raloxifene treatment influence back pain and disability among postmenopausal women with osteoporosis?

Clinical studies have suggested that postmenopausal women on estrogen replacement treatment are more likely to experience back pain and related disability compared to women who do not take estrogens. Raloxifene, a selective estrogen receptor modulator has estrogen-like effects on bone tissue, and antagonize the action of estrogens on endometrium and breast tissue. It is unknown if the treatment of osteoporosis with raloxifene has estrogen-like or opposite effects on back pain and functional capacity among postmenopausal women with osteoporosis. A total of 120 postmenopausal women with osteoporosis and chronic back pain were randomized to receive raloxifene 60 mg with 1,000 mg calcium, and 800 IU vitamin D daily or 1,000 mg calcium and 800 IU vitamin D daily. Pain intensity and pain-related disability were measured before treatment at 6 months and after 1 year. Repeated measures of ANOVA, did not reveal statistically significant differences over time, on pain intensity and disability scores, between groups studied. There was a trend in pain intensity changes during the follow-up period, but the differences between the groups were not statistically significant. It seems that treatment with raloxifene does not influence back pain and disability among postmenopausal women with osteoporosis. Raloxifene may have estrogenic agonist effects on nociceptive processing in the central nervous system.

Back Pain↗
PubMed2004

Chemoprophylactic and bactericidal efficacy of 80 mg gentamicin in a single and once-daily dosing.

OBJECTIVE: The objective was to examine the biodistribution, the chemoprophylactic, and the bactericide efficacy of 80-mg gentamicin single or once-daily dosing. STUDY DESIGN: Ninety-six patients who had had cesarean section or gynecological surgery received 80 mg gentamicin for chemoprophylaxis. A second group of 92 patients with Gram-negative infection received once-daily 80-mg gentamicin intramuscularly, combined with cefoxitin or ceforanide, for 5 days. Gentamicin serum and tissue concentration was determined 1 h after the first administration. RESULTS: The chemoprophylactic efficacy of gentamicin was 93.7%. The treatment efficacy was high in patients with chorioamnionitis and endometritis (92.9%), moderate in those with wound infection (69.5%), and less effective in those with septicemia (55.6%). Twenty-six percent of patients continued with antibiotics for infection control. The mean serum level was 4.48+/-0.49 and 5.56+/-0.66 microg/ml in obstetrical and gynecological patients respectively (p>0.05). Serum levels >4 microg/ml were achieved in 91% of patients. CONCLUSIONS: A single dose of 80 mg gentamicin offers chemoprophylaxis and achieves therapeutic serum-concentrations 1 h after administration. The 5-day combination of once-daily 80 mg gentamicin with a second-generation cephalosporin is effective in patients with chorioamnionitis and endometritis, but only moderately effective in those with wound infections and septicemia.

Adult↗
PubMed2004

Review of clinical and toxicological features of acute pesticide poisonings in Crete (Greece) during the period 1991-2001.

BACKGROUND: In Crete, the largest island of Greece, many pesticide formulations are increasingly used in agriculture in order to raise crop production. This study reviews a number of pesticide poisoning cases registered at the Center of Toxicology and Forensic Sciences Research at the University of Crete between 1991 and 2001. MATERIAL/METHODS: The medical records and toxicological data of the pesticide poisonings are presented. The analyzed samples were mainly blood and/or urine, but also gastric fluids and other tissues. Analysis involved a variety of techniques. RESULTS: Eleven poisonings caused by paraquat (7 men, 4 women, aged 15-58 years) are reported, five of which had fatal outcome. Initial paraquat plasma levels ranged between 0.4-165 pg/ml. Thirteen intoxications due to various organophosphorous agents are presented (11 men, 2 women, aged 13-69 years). Pesticide blood levels upon admission ranged from 1.0-108 pg/ml and there were six fatalities. Carbamate poisonings (4 men, 2 women, aged 32-60 years) were caused by methomyl (initial blood levels 1.6-57 mg/l) and resulted in death. A case of methyl bromide intoxication is also presented. CONCLUSIONS: The results of the study highlight the toxic and potentially lethal effects of pesticide formulations used in agriculture. Special seminars should be run to educate farmers on the proper use of these agents and the supply of pesticides should be restricted to those who follow all safety measures. Physicians should be trained to promptly identify and treat pesticide intoxications.

Adolescent↗
PubMed2004

Estimation of patient dose and associated radiogenic risks from fluoroscopically guided pedicle screw insertion.

STUDY DESIGN: An experimental model for the assessment of patient dose and associated radiogenic risks associated with pedicle screw internal fixation surgical procedures. OBJECTIVES: To provide data for the accurate determination of patient effective dose, gonadal dose, and entrance skin dose from fluoroscopically assisted pedicle screw insertion procedures and to investigate the potential of both stochastic and deterministic radiogenic effects to occur following such procedures. SUMMARY OF BACKGROUND DATA: There is increased concern on radiation exposure of patients undergoing fluoroscopically guided interventional procedures. METHODS: The cumulative screening time and dose area product, for each fluoroscopic projection used, were monitored in 20 patients undergoing pedicle screw internal fixation. The dose absorbed by each radiosensitive organ/tissue was determined from direct measurements obtained using an anthropomorphic phantom appropriately loaded with thermoluminescence dosimeters. RESULTS: An average pedicle screw insertion procedure requires 1.2 minutes and 2.1 minutes of fluoroscopic exposure along anteroposterior and lateral projections, respectively, resulting in a dose area product of 232 cGy cm and 568 cGy cm, correspondingly. Gender-specific normalized data for the determination of effective, gonadal, and entrance skin dose to patients undergoing fluoroscopically guided pedicle screw internal fixation procedures were derived. The effective dose from an average procedure was 1.52 and 1.40 mSv and the gonadal dose 0.67 and 0.12 mGy for female and male patients, respectively. The average radiogenic risks for fatal cancer and genetic defects were 115 and 4 per million of patients treated, respectively. Induction of skin injuries might be induced when fluoroscopy along the lateral projection is highly extended and the source to skin distance is kept low. CONCLUSIONS: Patient dose and radiogenic risks associated with an average pedicle screw internal fixation procedure are tolerable. However, for young patients with complex spinal disorders requiring extended fluoroscopy, radiogenic risks may be considerable. Present data may beused for estimation of effective dose, gonadal dose, and entrance skin exposure and associated radiogenic risks to patients undergoing fluoroscopically guided pedicle screw insertion in any institution.

Adult↗
PubMed2004

Factors associated with good outcome using lateral mass plate fixation.

The immediate and long-term outcomes of 70 consecutive patients who underwent subaxial lateral mass fixation between June 1996 and June 2001 were reviewed. Intraoperative fluoroscopy and somatosensory evoked potential (SEP) monitoring were used in all patients. Immediate postoperative computed tomography (CT) was performed to determine screw trajectory and placement. Follow-up ranged from 2 to 7 years. Postoperative CT showed 206 (58%) of 356 screws had unicorticate and 42% bicorticate purchase. Furthermore, 96 (27%) screws had suboptimal trajectory, but only 5 of these screws minimally penetrated the foramen transversarium without resultant vascular or neurological sequelae. A sudden unilateral intraoperative SEP amplitude decrease during screw placement in 2 patients resolved with screw removal and alteration of screw trajectory. The overall fusion success rate was 91.5% and screw pull-out developed in 2 patients. The recommended drilling technique and trajectory (15 degrees - 25 degrees rostral in the sagittal plane, 20 degrees - 30 degrees lateral in the axial plane), supplemented bone grafting, and intraoperative SEP monitoring are all associated with good screw placement, fusion, and neurological outcome and are recommended for all lateral mass fusion procedures.

Adult↗
PubMed2004

Surgical decompression for cervical spondylotic myelopathy: correlation between operative outcomes and MRI of the spinal cord.

Forty-two patients who underwent decompressive surgery for cervical spondylotic myelopathy were studied. The pre- and postoperative magnetic resonance imaging (MRI) findings and the Japanese Orthopedic Association score were analyzed to evaluate whether the different appearances of intramedullary high-signal intensity on T2-weighted MRI are related to the surgical prognosis. Magnetic resonance imaging signal intensities were classified as type 0 if no intramedullary high-signal intensity on T2-weighted images was noted, type 1 if high-signal intensity involved only one segment, and type 2 if high-signal intensity extended over two segments. Statistical analyses of the recovery ratio showed that type 0 and type 1 intramedullary high-signal intensity indicates better prognosis than type 2.

Adult↗
PubMed2004

Spontaneous and simultaneous bilateral rupture of the quadriceps tendon. A case report.

Simultaneous bilateral rupture of the quadriceps tendon has rarely been reported; it generally occurs in association with chronic metabolic disorders, such as chronic renal failure, obesity, diabetes mellitus and secondary hyperparathyroidism. The case presented here was in an 85-year-old man with no known risk factors, who sustained simultaneous and spontaneous rupture of both quadriceps tendons. The patient suffered from spinal stenosis and degenerative changes in the knee menisci. These findings suggest that instability of the knee due to meniscal damage, and quadriceps weakness as a result of spinal stenosis, may have played a significant role in the pathogenesis of this injury.

Accidental Falls↗
PubMed2003

Prediction of Cobb angle in idiopathic adolescent scoliosis.

We did a prospective study of 291 children and adolescents with idiopathic scoliosis to identify possible correlations between clinical (scoliometer value, age, height) and radiographic (Cobb angle, Nash-Moe rotation, Risser iliac apophysis classification) parameters to predict the curve angle. There was a statistically significant correlation between thoracic, thoracolumbar, and lumbar scoliometer values and the thoracic, thoracolumbar, and lumbar Cobb angles, respectively (Pearson's r-0.685, 0.572, and 0.677, respectively). There was a statistically significant correlation between Cobb angle in the thoracic, thoracolumbar, and lumbar spine and the patients' age and height. Mathematical formulas that predict the Cobb angle of thoracic, thoracolumbar, and lumbar scoliosis using the scoliometer measurements are reported.

Adolescent↗
PubMed2003

Complications and problems related to pedicle screw fixation of the spine.

This retrospective study analyzes the complications and the problems developed during and after pedicle screw fixation in patients with spinal disorders and trauma. One hundred twelve patients were treated using the Cotrel-Dubousset pedicle screw fixation system for degenerative disease (57 patients), trauma (42 patients), infection (eight patients), and tumor (five patients) of the lumbar or thoracolumbar spine. The average age of the patients was 47 years and the average followup was 35 months. Forty-seven general complications were seen in 41 patients (36.5%). In addition, hardware failures were observed in 12 patients (10.7%), junctional problems were seen in five patients (4.5%), problems in the instrumented segments were seen in 39 patients (34.7%), and problems of balance occurred in five patients (4.5%). Although the rate of the reported complications was high, the final outcome of the patients was not affected significantly. Placement of the pedicle screws in the thoracolumbar and lumbar spine is a technically demanding procedure. It should be used by experienced and qualified surgeons who are aware of the pitfalls associated with its use.

Adolescent↗
PubMed2003

Treatment of closed unstable metacarpal fractures using percutaneous transverse fixation with Kirschner wires.

BACKGROUND: The vast majority of metacarpal bone fractures are stable and are treated conservatively; however, when surgical intervention is to be preferred, many different operative procedures have been described. The purpose of this prospective study was to assess the anatomic and functional outcome of percutaneous transverse fixation with Kirschner wires (K-wires) of closed metacarpal neck, shaft. and intra-articular fractures of the base of the fifth metacarpal. METHODS: Twenty-four consecutive patients with 25 closed metacarpal fractures were treated with this technique between 1999 and 2001. Under fluoroscopy, closed reduction and osteosynthesis with three K-wires, one proximally and two distally, was performed on the fracture site. All patients were reviewed clinically and radiologically after 3 weeks, 6 weeks, and 3 months. RESULTS: The postoperative dorsal angulation ranged from 0 to 3 degrees. No measurable metacarpal shortening was observed. Callus formation was obvious in all fractures at 6 weeks. No complications were recorded, and all patients were cosmetically and functionally satisfied. CONCLUSION: Treatment of closed metacarpal neck, shaft, and intra-articular fractures of the base of the fifth metacarpal with percutaneous transverse pinning, using two K-wires distally and one proximally, has shown excellent functional and anatomic outcome.

Adult↗
PubMed2003

Functional evaluation after primary flexor tendon repair in zone II.

The purpose of this prospective study was to evaluate the results of primary treatment of flexor tendon laceration in zone II according to Verdan's zone system. Special emphasis was given to the postoperative rehabilitation program. Nineteen patients (23 fingers) with laceration of the flexor tendons in zone II were treated operatively. Twelve males and seven females were included in the study. Their mean age was 28 years (range, 16 to 50 years). In 12 cases a concomitant laceration of the digital nerve was present. In all cases primary repair of all injured tendons and nerves was performed and a dorsal splint was applied. On the third to fifth postoperative day an exercise program commenced involving passive flexion-active extension of the injured fingers. Eighteen (22 fingers) of 19 patients completed the follow-up. The results were evaluated according to Strickland's original classification system. The result was excellent in 15 cases, good in five and fair in two. After primary repair of injured flexor tendons, a program of close follow-up, early protected motion and unrestricted motion of the interphalangeal joints offers the best chance of restoring optimal function to the hand.

Adolescent↗
PubMed2002

No difference in clinical outcome after posterolateral lumbar fusion between patients with isthmic spondylolisthesis and those with degenerative disc disease using pedicle screw instrumentation: a comparative study of 112 patients with 4 years of follow-up.

We compared the clinical outcome after spinal fusion between patients with isthmic spondylolisthesis and those with degenerative disc disease of the lumbar spine, using multiple logistic regression analysis. A questionnaire describing medication, pain, vocational status and patient satisfaction was mailed to all the patients at a median interval of 4 years after their operation. Fusion was evaluated on plain radiographs at a minimum of 12 months after surgery, and patients were classified as fused or not fused. The overall satisfaction rate was 70%. The results of the present study showed no difference in the outcome after spinal fusion between the two groups of patients. The factors that significantly increased the likelihood of an optimal result - defined as patient satisfaction, return to work, and reduced medication - were male gender, being in work prior to surgery, and being a non-smoker. Since spinal fusion is an expensive treatment with potentially serious risks, and leaves one-third of the patients with an unsatisfactory result, we believe that more studies focusing on the indications for surgery should be performed.

Adolescent↗