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1.
Anna C. Rienmüller Sandro M. Krieg Franziska A. Schmidt Elias L. Meyer Bernhard Meyer 《The spine journal》2019,19(1):113-120
Background Context
The concept of dynamic stabilization (DS) of the lumbar spine for treatment of degenerative instability has been introduced almost two decades ago. Dynamic stabilization follows the principle of controlling movement in the coronal plane by providing load transfer of the spinal segment without fusion and, at the same time, reducing side effects such as adjacent segment disease (ASD). So far, only little is known about revision rates after DS due to ASD and screw loosening (SL).Purpose
The present study aimed to evaluate the longitudinal revision rates following dynamic pedicle screw stabilization in the lumbar spine and to determine specific risk factors predictive for ASD, SL, and overall reoperation in a large cohort with considerable follow-up.Design
We carried out a post hoc analysis of a prospectively collected database in a level I spine center.Patients Example
The patient sample comprised 283 (151 female/132 male) consecutive patients suffering from painful degenerative lumbar segmental instability with or without spinal stenosis who underwent DS of the lumbar spine (Ulrich Cosmic, Ulrich Medical, Ulm, Germany) between January 2008 and December 2011.Outcome Measures
Longitudinal reoperation rate and risk factors predictive for revision surgery were evaluated.Methods
We analyzed the longitudinal reoperation rate due to ASD and SL and overall reoperation. Risk factors such as age, gender, body mass index, lumbar lordosis (LL), number of segments, and number of previous surgeries were taken into account. Regular and mixed model logistic regressions were performed to determine risk factors for revision surgery on a patient and on a screw level.Results
The mean age was 65.7±10.2 years (range 31–88). One hundred thirty-two patients were stabilized in 1 segment, 134 in 2 segments, 15 in 3 segments, and 2 patients in 4 segments. Reoperation rate for ASD and SL after 1 year was 7.4 %, after 2 years was 15.0%, and after a mean follow-up of 51.4±15 months was 22.6%. Reasons for revision were SL in 19 cases (6.6%), ASD in 39 cases (13.7%), SL and ASD in 6 cases, hematoma in 2 cases (0.7%), cerebrospinal fluid fistulae in 3 cases (1.1%), infection in 6 cases (2.1%), and implant failure in 1 case (0.4%). The patients' age, the number of stabilized segments, and the number of previous surgeries and postoperative LL had a significant influence on the probability for revision surgery.Conclusions
Reoperation rates after DS of the lumbar spine are comparable with rigid fixations. The younger the patient and the more segments are involved, the lower the LL and the more previous surgeries were found, the higher was the risk of revision. Risk of revision was almost twice as high in men compared with women. We therefore conclude that for clear clinical indication and careful evaluation of preoperative imaging data, DS using the Cosmic system seems to be a possible option. The presented data will help to further tailor indication and patient selection. 相似文献2.
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Leonidas JC; Berdon WE; Valderrama E; Neveling U; Schuval S; Weiss SJ; Hilfer C; Godine L 《Radiology》1996,198(2):377
6.
JC Sitek† M Loeb‡ JR Ronnevig¶ 《Journal of the European Academy of Dermatology and Venereology》2007,21(7):891-896
BACKGROUND: Since 1997, a number of trials have shown promising results in treating generalized vitiligo with narrowband ultraviolet B (UVB) both in adults and children. However, there is little knowledge concerning the duration and permanency of the treatment-induced repigmentation. OBJECTIVE: Our main objective was to perform a follow-up trial of successfully treated patients receiving narrowband UVB for generalized vitiligo. METHODS: We have investigated to what degree the treatment-induced repigmentation remains stable for up to 2 years post-treatment. We performed an initial open trial including 31 patients with generalized vitiligo. They received narrowband UVB thrice weekly for up to 12 months. Patients experiencing > 75% repigmentation were defined responders and were included in the follow-up trial. Responders were followed every 6 months for up to 2 years after cessation of treatment. We observed the pigmentation status and registered any changes indicating loss of pigmentation and relapse. RESULTS: Eleven of the 31 treated patients were included in the follow-up trial. Six patients had relapse and five patients had stable response 24 months after cessation of treatment. Four out of six relapses were within 6 months post-treatment. CONCLUSION: In our study population of 31 patients with generalized vitiligo, five patients (16%) experienced > 75% stable repigmentation 2 years after cessation of a treatment programme of up to 1 years narrowband UVB therapy. 相似文献
7.
Ongoing pregnancies after intracytoplasmic injection using cryopreserved testicular spermatozoa 总被引:4,自引:2,他引:2
Perraguin-Jayot S; Audebert A; Emperaire JC; Parneix I 《Human reproduction (Oxford, England)》1997,12(12):2706-2709
We report two clinical pregnancies occurring after intracytoplasmic sperm
injection (ICSI) using cryopreserved spermatozoa obtained from testicular
biopsy, made in two different infertility situations in our clinic. The
first patient showed a secretory azoospermia associated with elevated serum
follicular stimulating hormone (FSH) level and spermiogenesis maturation
arrest. The second patient was affected by azoospermia resulting from
bilateral epididymal obstruction. Spermatozoa present in the wet
preparation of testicular biopsy made on the day of scrotal exploration
were cryopreserved within the testicular tissue for both men.
Intracytoplasmic injections were performed at a later date, using
spermatozoa prepared from frozen-thawed tissues. In each case, three
embryos were obtained and transferred in utero. The transfers resulted in a
twin pregnancy for the first case, and in a singleton pregnancy for the
second. Living foetuses were seen in the ultrasound scan at the 7th week
and both pregnancies are proceeding to date beyond 30 weeks without
complications.
相似文献
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Satoshi Hisano Winnie Chan Kay Latta Richard J Krieg Jr. James CM Chan 《Clinical and experimental nephrology》1997,1(3):179-186
Growth retardation is a major complication in children with uremia. Protein restriction, calorie deficit, metabolic acidosis,
renal osteodystrophy, and endocrinologic disturbances contribute to the growth failure. The effect of these factors on growth
retardation can be attenuated in part by therapy with vitamin D metabolites, adequate nutrition, alkalization, and dialysis.
Linear growth in children with uremia is markedly retarded despite normal or increased levels of circulating serum growth
hormone. An increased growth hormone level in children with uremia is due to normal growth hormone secretion from the pituitary
gland and impaired growth hormone clearance in the kidney. However, the elevated growth hormone level does not lead to a commensurate
rise in serum insulin-like growth factor I (IGF-I); the serum IGF-I level is decreased or normal in relation to the degree
of renal failure. This discrepancy suggests growth hormone resistance in the liver in uremia. Recent molecular techniques
open a new era in studying the gene expression for growth hormone or IGF-I. There is no doubt today that growth hormone treatment
has the beneficial effect of growth promotion in children with uremia, which also suggests endogenous growth hormone resistance
in target organs or target cells in uremia. 相似文献