Biomedical subjects

R Kotz

Publications and source records attributed to R Kotz.

At least 163 records · Page 9Linked to original sources

PubMedDate not supplied

[Arthroscopic menisectomy in older patients: assessing health-related quality of life].

AIM: Little information is available on partial arthroscopic menisectomy in patients 60 years of age or older. Due to the co-morbidity of meniscal tears and osteoarthritis in this age group, the effectiveness of this procedure is controversial. The purpose of this study was to evaluate the outcome of this procedure in terms of function and mobility in patients 60 years of age or older. METHOD: Between 1990 and 1999, 1920 arthroscopies of the knee were performed in a single primary care institution, and 51 patients, 60 years of age or older, had a partial arthroscopic menisectomy done. Outcomes were rated using the SF-36 Health Survey and a specially designed questionnaire including items of published scores. RESULTS: The mean age at surgery was 67 years (range: 60.3 - 78.9) and the mean follow-up was 5 years (range: 2 - 12). Due to persistent pain, 4 patients underwent a second operation including knee replacement in 3 cases and a high tibial osteotomy in 1 case. 41 patients (87.1 %) stated the arthroscopy had improved their quality of life. In terms of pain and daily life activities, the majority of the subjects showed an improvement after surgery. The SF-36 showed no clinically relevant difference compared to the control in all but one subscale. CONCLUSION: Despite of the presence of osteoarthritis in this age group, arthroscopic partial menisectomy can improve pain, function and mobility in the mid-term course.

Aged↗

PubMedDate not supplied

[Neoadjuvant chemotherapy of osteosarcoma. Preliminary results of the cooperative COSS-86 osteosarcoma study].

The neoadjuvant study COSS-86 was undertaken aiming at (1) improving the cure rate in osteosarcoma by early intensification of chemotherapy in high risk patients and (2) investigating the effect of intraarterial (i.a.) versus intravenous (i.v.) administration of cisplatinum. (1) Ifosfamide was added to the well proven drugs in osteosarcoma such as doxorubicin, high-dose methotrexate and cisplatinum in patients with large tumor size or/and high portion of chondroid groundsubstance or/and scintigraphic nonresponse after 4 weeks of preoperative chemotherapy. It was given in combination with cisplatinum. (2) The same patients were allocated to either the intraarterial study arm or the intravenous control arm of the study. The response rate (greater than 90% tumor necrosis) of all patients was 75% (88/118). No advantage in response rate was achieved by i.a. infusion of cis-platinum within this highly efficient 4-drug regimen (i.a. 75% (33/44) vs. i.v. 74% (35/47)). The significantly improved response rate in this study results in a better metastasis free survival (MFS) of 77% (+/- 4) at 4 years.

Adolescent↗

PubMedDate not supplied

[Neoadjuvant chemotherapy of osteosarcoma. Results of the cooperative studies COSS-80 and COSS-82 after 7 and 5 years].

The analysis of the results of two German Pediatric Oncology (GPO) cooperative, neoadjuvant chemotherapy trials after a followup of 7 (COSS-80) and 5 years (COSS-82) allows several conclusions concerning both systemic and local treatment of patients suffering from osteosarcoma. A metastasis free survival rate (MFS) of 59% was reached in the reduced study group of the first study, COSS-80. In addition to size of the primary tumor, the extent of chemotherapy induced devitalisation was very closely related to the probability of survival without systemic recurrence. Following this observation, it was the aim of the next study, COSS-82, to improve the MFS of patients with poorly responding tumors by altering their postoperative chemotherapy regimen. However, this "salvage" approach failed. Moreover, an effort to reduce treatment related toxicity by sparing some patients from the side effects of two particularly toxic drugs, adriamycin (ADR) and cisplatinum (CDDP), by only giving these postoperatively and only after insufficient tumor response to preoperative therapy, failed (MFS of the study arm of COSS-82 45% at 5 years vs. 68% for the control arm with primary use of ADR and CDDP, p less than 0.05). The value of an effective primary chemotherapy is further enhanced by the observation, that en bloc resection of tumors which were poor responders to preoperative therapy was associated with an increased risk of distant metastases when compared with amputation and rotation plasty, while this was not the case for good responders. In conclusion, both systemic tumor control and optimal local therapy require that all effects drugs are to be used as early as possible in the primary treatment of osteosarcoma, in order to enforce maximum tumor cell destruction and hence an optimistic outlook for the individual patient.

Antineoplastic Combined Chemotherapy Protocols↗

PubMedDate not supplied

[The German Society of Pediatric Oncology Cooperative Ewing Sarcoma Studies CESS 81/86: report after 6 1/2 years].

The GPO Cooperative Ewing's Sarcoma Study (CESS 81 with 10 months four-drug combination chemotherapy (vincristine, actinomycin D, cyclophosphamide, and adriamycin = VACA) and local control with surgery and/or radiation, following week 18, resulted in a Kaplan-Meier estimated disease-free survival of 51% after 6 1/2 years (51/93 patients disease-free). Tumor volume and histological response to primary chemotherapy were identified as most significant prognostic factors. As a consequence, the CESS 86 regimen was stratified according to risk of relapse. Standard risk patients (extremity tumors less than 100 ml tumor volume) were continued on VACA chemotherapy. In high risk patients (extremity tumors greater than 100 ml tumor volume, central tumors), cyclophosphamide in conventional dose (1200 mg/m2/course) was replaced by high doses of ifosfamide (6 g/m2/course) with mesna uroprotection (VAIA). Local control was obtained following week 9. Patients with radiation were randomised for conventional fractionation or accelerated split-course hyperfractionation. The study was piloted from February to December 1985: 27/37 patients were disease-free on October 1, 1987. The ongoing trial was started on January 1, 1986. On October 1, 1987. 63/66 patients were disease-free. In patients with large primaries, according to Kaplan-Meier life-table analysis, the disease-free survival was significantly better in patients receiving VAIA chemotherapy, compared to the previous VACA regimen. The toxicity of both combination chemotherapy regimens was comparable.

Antineoplastic Combined Chemotherapy Protocols↗

PubMedDate not supplied

[Results of treatment of primary metastatic Ewing sarcoma. A retrospective analysis of 48 patients].

The clinical presentation of the disease and the results of treatment in 48 patients with metastases at diagnosis of Ewing's sarcoma, entered into the Cooperative Ewing's Sarcoma Studies (CESS) 1981 and 1986 of the German Society of Pediatric Oncology (GPO), were analysed. The period of observation ranged from 1 to 82 months, the median relapse-free time was 26 months. There was a male predominance of 35 to 13, which was even more pronounced in patients older than 15 years. The predominant localization of the primary tumor was the pelvic region, followed by the extremities, the chest wall, and the spine. The most common site of primary metastases were the lungs, followed by bone and bone marrow. Nine patients presented with combined metastases. The disease-free survival according to Kaplan-Meier life-table analysis was 18% after 7 years. Best results were obtained in patients with pulmonary metastases only, who underwent surgical resection of the primary tumor and received radiation to the lungs. Without bone marrow transplantation the prognosis of patients with bone metastases was extremely poor.

Adolescent↗

PubMedDate not supplied

[Results of the COSS-77 and COSS-80 studies on adjuvant chemotherapy in osteosarcoma of the extremities].

In the first study, COSS-77, 100 patients with OS were treated for 12 months according to a CT-protocol consisting of high-dose methotrexate (HD-MTX), adriblastine (ADR) and cyclophosphamide (CP). At 40 months the expected continuous disease-free survival (CDFS) rate of the 71 evaluable patients was 55%. After exclusion of local recurrences (n = 2) and fatal chemotherapy toxicities (n = 0) a reduced group of 69 patients remained and the expected CDFS rate at 40 months became 56%. In the second study, COSS-80, the MTX dose was doubled. Two groups were randomly selected, one of which received cisplatinum (CPL) and the other the triple drug combination bleomycin + CP + dactinomycin (BCD) in addition to MTX and ADR, both groups being treated for 8 months. Furthermore some randomly selected patients received fibroblaste-interferon (IF). The expected CDFS rate at 40 months of the 115 evaluable COSS-80 patients was 67%. 106 patients remained in a reduced group defined as above (4 local recurrences and 5 CT toxicities) in which the expected CDFS rate at 40 months was 73%. This is significantly better (p less than 0.05) than the results obtained from the COSS-77 group. No differences were found between the CPL and BCD arms of the COSS-80 group or between the arms receiving or not receiving IF. A significant increase in the CDFS rate for young (less than 12 years) and male patients over that in COSS-77 was observed in COSS-80, probably due to the increased MTX dose.(ABSTRACT TRUNCATED AT 250 WORDS)

Amputation, Surgical↗

PubMedDate not supplied

[The use of a rapid infusion system in orthopedics].

Major orthopedic surgery such as partial resection of the pelvis and subsequent implantation of a prosthesis is highly connected with massive bleeding. Therefore we tested the hypothesis that the use of a rapid infusion device, which was originally designed for liver transplantations, can prevent hypovolemic shock. We studied 20 patients: in one group (n = 10) the iv volume was given in a conventional way (37 degrees C) by use of pressure infusion bags. Patients of the second group (n = 10) received the iv volume via the Rapid Infusion system (Haemonetics Corp., Braintree, MA). We can conclude that with this new device for rapid volume replacement it is possible to keep the patient's vital functions stable even during times of excessive bleeding and to prevent from metabolic consequences following hypovolemic shock.

Adult↗

PubMedDate not supplied

[KMFTR (Kotz Modular Femur Tibia Reconstruction System) modular tumor endoprosthesis system for the lower extremity].

206 patients with tumorendoprosteses of the KMFTR-type at the lower extremity were operated at the Institute Rizolli Bologna and at the University Clinic of Vienna. The minimum follow up was 2 years (mean 3.2, max. 8 years). In order to bridge the defect caused by tumor resection the proximal femur was replaced in 42 cases, the distal femur in 119 cases and in 6 patients a total femur prosthesis was used. The proximal tibia was replaced in 35 cases and in 4 cases a total knee prosthesis was implanted. Clinical evaluation according to Enneking revealed 71.6% excellent and good results. In 83.4% the radiological score was higher then 20. We saw deep infections in 8.2% (17 patients), breakage of the prosthesis in 6.8% and aseptic loosening in 5.8%. 3 patients had to be amputated due to infection. In the remaining cases of infection in 66% of the patients healing was observed. All cases of aseptic loosening or breakage could be revised successfully by an exchange of the prostheses and therefore salvage of the leg was achieved.

Adolescent↗

PubMedDate not supplied

[The limits of saving the extremity--amputation versus resection].

On the basis of the extensive data contained in the Vienna Bone Tumor Register, i.e. 839 primary malignant bone tumors, as well as of 554 cases treated at the Orthopedic Department of the University of Vienna Medical School, a comparison between the methods of surgery applied at pelvis and extremities during the past two decades can be drawn. Resectional therapy had been performed in twice as much patients as amputation therapy, and barely 20%, mostly with multiple metastases, had been merely treated with palliative surgery or were just biopsied and underwent chemo- and radiotherapy. An analysis of amputations and resections, subdivided into pelvis and sacrum resections, resectional reconstructions and resectional reimplantations at the extremities, shows approximately the same low incidence of local recurrences in the groups amputation versus resection, but a significantly higher involvement of pelvis and sacrum resections as well as no local recurrences in the group of 48 resectional reimplantations. As regards the oncologic radicality of surgical margins, in cases of resections, as compared to amputations, about twice as much inadequate operations had to be accepted, though. The fact that the local recurrences did not increase to the same degree, but were approximately equilibrated, seems to be due to the new chemotherapeutic treatment which had been initiated at the same time as the frequent application of resectional therapy. The conservation of extremities contains twice as high a risk of inadequate operation, but it is, in cases of effective chemotherapy, comparable with the former results of amputations, as regards local recurrences.(ABSTRACT TRUNCATED AT 250 WORDS)

Amputation, Surgical↗

PubMedDate not supplied

[Surgical treatment of spinal metastases].

87 patients were treated for metastatic disease of the spine between 1970 and 1992. In the majority of the patients anterior decompression and stabilization was performed. The posterior approach was chosen only in case of predominant infiltration of the dorsal parts of the vertebra or in case of inaccessibility of the tumor via an anterior approach. The most common primary tumors were cancer of the breast, kidney and thyroid. Overall survival was 15.1 months. Only patients with metastases of thyroid cancer showed a statistically significant longer survival. Clinical results showed an improvement of pain in 83% and preoperative neurologic dysfunction could be improved in 53% of the patients. Our results suggest that surgical treatment improves life quality also in patients with short life expectancy. Patients who are expected to have longer survival times should be treated according to the general principles of stabilizing spine surgery.

Bone Plates↗

PubMedDate not supplied

[Total spondylectomy in metastasizing osteosarcoma of the spine--case report].

We report on a case of a 28 year old male patient, on whom in 1984 a rotation plasty was performed, due to an osteogenic sarcoma of the left distal femur. Eight years after the incidence of the primary tumor, a metastasis of the osteogenic sarcoma in the twelfth thoracic vertebra occurred. The tumor extended from the vertebral body to one pedicle and did not pass over the bony limits. After neoadjuvant chemotherapy an total spondylectomy was performed. Due to this method wide surgical margins could be achieved. Up to now these margins could only be executed with malignant bone tumors located in the extremities, whereas they could not be realized with the methods of spondylectomy, that were already introduced. By this case we want to present an innovative operation method for the treatment of primary malignant tumors or solitary metastasis of the spine, with the help of which we could give these patients a promising life expectancy.

Adult↗

PubMedDate not supplied

[Salter's pelvic osteotomy in the treatment of congenital hip dislocation and hip dysplasia with special reference to pelvic tilt].

On the basis of 63 Salter pelvic osteotomies which were performed in 57 patients with congenital dislocation and subluxation of the hip between 1970 and 1986 at the Orthopaedic University Clinic of Vienna, we tried to work out the reasons for the rate of failures of 29% in our material. The mean age at operation was 4.1 years (1.5-18), that at follow up 15.7 years (4.6-28). We based our assessments on the clinical and radiological criteria of the Commission for the Study of Hip Dysplasia of the German Society of Orthopaedics and Traumatology. The number of failures at follow up (hip value III + IV) increased from 25%, if the operation was done before the age of four years, to 41%, if it was performed at a later age. In the latter group we were not able to observe any spontaneous improvement, which was typical for the younger age group. A moderately pathologic hip dysplasia (hip value III) could be improved to a normal value at follow up in 87%, an extremely pathologic one just in 50% of the cases. In just some of the patients we found postoperatively a tilt of the distal pelvic fragment, which could be registered by the oval shape of the foramen obturatum. Above all in young children a pelvic tilt was rare because of the elasticity of the triradiate cartilage. Out of 37 evaluable cases a tilt of the distal pelvic fragment by the operation could be verified in only 12 cases.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMedDate not supplied

[Muscle function of the thigh 10 years following a malignant bone tumor and implantation of a tumor prosthesis in the knee].

To objectify the muscle function of 5 patients ten years after implantation of a tumor endoprosthesis of the knee simultaneous muscle force and IEMG was recorded. The muscular activity in the operated leg was found to be reduced for the extension muscles (8-20%) and for the flexion muscles (28-52%) when comparing to the normal leg. Knee extension of the operated leg resulted from the function of the rectus femoris muscle. During normal exercise in daily life all patients were not handicapped und some of them did sport.

Adolescent↗

PubMedDate not supplied

[Surgical therapy of metastases of the pelvis and sacrum].

We are reporting on 42 surgical and 5 conservative treatment approaches in metastases of the pelvis and sacrum. With an average disease-free survival of 14.4 months the majority of the lesions were resected intralesionally. In the area of the ischium and the pubis resection alone was done without further stabilizing measures. If the resection was in the area of the iliac wings, stabilization was achieved by means of osteosynthesis in 50% of the cases. Periacetabular resections required reconstruction with endoprotheses in all cases. In patients with good prognosis and solitary metastases also extralesional resections were performed. Reoperated embolization was used in advanced stages of the disease or if the metastases were not easily accessible surgically. Because of the complexity of pelvic resections and the often considerable loss of function, patients with metastases are often treated with intralesional resection and osteosynthesis. In exceptional cases, if radiotherapy had failed or multiple intralesional resections were followed by recurrences, we feel however that extralesional resection should be attempted with good prognosis for the patient.

Adenocarcinoma↗

PubMedDate not supplied

[Algodystrophy in pregnancy].

Algodstrophy during pregnancy occurs very seldom. Indeed there are only 28 exactly described cases on record and not one of these in German. The symptoms are, however, very severe and considerably affect the well-being of the patients. According to the most recent findings, the MRT examination should be the most suitable diagnostic procedure; a biopsy is not necessary. The focus of the therapy is the treatment of the symptoms. The etiology is still obscure. From the analysis of the described cases, however, the combination of hormones during pregnancy seems to be the most significant factor.

Adult↗

PubMedDate not supplied

[Neoadjuvant therapy for localized osteosarcoma of extremities. Results from the Cooperative osteosarcoma study group COSS of 925 patients].

BACKGROUND: Owing to twenty years of multicentric interdisciplinary cooperation, the COSS group has been able to collect data on a large group of osteosarcoma patients treated by neoadjuvant therapy. This paper reviews results achieved in patients with localized extremity tumors. PATIENTS AND METHODS INCLUSION CRITERIA: Registration into a completed neoadjuvant COSS-Study. Histologically confirmed, primary, localized, high-grade, central osteosarcoma of an extremity; age < 40 years; no pretreatment; interval diagnosis to chemotherapy < or = 3 weeks; no severe comorbidity. Chemotherapy: HD-methotrexate +/- doxorubicin +/- cisplatin +/- ifosfamide +/- BCD. Scheduled local therapy: Surgery. RESULTS: 925 evaluable patients from 101 institutions. Median age 15 years, m:f 1.4:1. Primary site: femur 510, tibia 251, humerus 100, fibula 51, other 13. Tumor-size < 1/3 of the involved bone 616, > or = 1/3 304. Definitive surgery in 903/925 cases, 443 limb salvage procedures. Good response (> 90% necrosis) in 469/806 (58.2%) evaluated tumors. Median follow-up for surviving patients: 5.42 years. Actuarial survival after 5 and 10 years: 72.5% (95%-CI 69.3-75.7) and 66.3% (62.5-70.0), relapse-free 62.1% (58.7-65.4) and 59.4% (55.8-63.0). 683/925 alive (601 first remission), 242 deceased (212 tumor progression, 30 other causes). 66.2% (97.3%) of all relapses within 2 (5) years. Prognosis correlates with tumor-size (< vs. > or = 1/3: 69.9% vs. 58.3% at 10 years) and -site (tibia: 74.2%, humerus: 54.5%) and -response (good vs. poor: 78.2% vs. 52.5%) (all p < 0.01). Actuarial 10-year survival by response grading I-VI according to Salzer-Kuntschik 80.9%, 82.8%, 71.1%, 60.7%, 47.7%, 27.3%. COSS-studies with preoperative 4-drug therapy more efficacious than less aggressive protocols. No impact of doxorubicin scheduling (sequential: rapid vs. 48 h-continuous infusion) or cisplatin scheduling (randomized: 5 h vs. 72 h-infusion) on prognosis detected. CONCLUSIONS: Intensive multiagent chemotherapy and delayed surgery for localized extremity osteosarcoma led to excellent oncologic results in the COSS-studies. Tumor-size, -site, and -response as well as the intensity of upfront chemotherapy correlated with outcome. Giving doxorubicin and cisplatin by continuous infusions did not result in discernible prognostic disadvantages.

Adolescent↗

PubMedDate not supplied

[Effect of a local surgical procedure on the incidence of metastases following neoadjuvant chemotherapy of osteosarcoma].

Following preoperative chemotherapy of 9-18 weeks duration limb salvage procedures were performed instead of ablative surgery in about 1/2 of the patients (pts). Overall continuous disease-free survival rate is 69% (80/115) at 37 (21-51) months. 5 pts died from therapy related complications, 4 developed a local failure (2 following amputation and 2 following limb salvage each) and 26 pts developed pulmonary metastases. The incidence of pulmonary metastases after en bloc resection, but not after shank rotation plasty, was found to be significantly increased over that after ablative surgery (83% vs 60% metastases free survival (MFS) at 40 months, p less than 0.05). The outcome was most unfavourable following en bloc resection of large tumors (36% MFS) and of tumors poorly responding to preoperative chemotherapy. Delaying surgery for preoperative chemotherapy in itself did not influence MFS-rate but it enabled a thorough planing and preparation of surgical procedures. Chemotherapy has very much improved the prognosis of osteosarcoma, trials on limb salvage surgery are indicated therefore. However, these procedures appear to be hazardous by increasing the rate of pulmonary metastases. Until the underlying mechanisms are not uncovered and preventive strategies worked out, limb salvage surgery in osteosarcoma has to be regarded and handled as an experimental procedure.

Amputation, Surgical↗

PubMedDate not supplied

[The incidence of recurrence in phenol treated and non-phenol treated bone cavities following intralesional resection of non-malignant bone tumors].

Between 1955 and 1986 intralesional excisions were performed at Vienna University Orthopedic Clinic on 103 patients suffering from aneurysmatic or juvenile bone cysts, chondromyxoid fibromas or giant cell tumors. In 31 patients phenol was applied to the wall of the bone cavity after this had been carefully curetted or fraised. The chemical cauterization effect is intended to destroy any remaining tumor cell remnants. The cavity is then filled with autologous or homologous spongiosa. In a total of 72 nonphenolized bone cavities there were 21 recurrences (29.1%). By using phenol following intralesional excision of nonmalignant bone tumors in 31 patients the recurrence rate was significantly lowered (3 recurrences - 9.7%).

Adolescent↗