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101.
102.

Background

The genu valgum deformity seen in the Ellis-van Creveld syndrome is one of the most severe angular deformities seen in any orthopaedic condition. It is likely a combination of a primary genetic-based dysplasia of the lateral portion of the tibial plateau combined with severe soft-tissue contractures that tether the tibia into valgus deformations. Progressive weight-bearing induces changes, accumulating with growth, acting on the initially distorted and valgus-angulated proximal tibia, worsening the deformity with skeletal maturation. The purpose of this study is to present a relatively large case series of a very rare condition that describes a surgical technique to correct the severe valgus deformity in the Ellis-van Creveld syndrome by combining extensive soft-tissue release with bony realignment.

Methods

A retrospective review examined 23 limbs in 13 patients with Ellis-van Creveld syndrome that were surgically corrected by two different surgeons from 1982 to 2011. Seven additional patients were identified, but excluded due to insufficient chart or radiographic data. A successful correction was defined as 10° or less of genu valgum at the time of surgical correction. Although not an outcomes study, maintenance of 20° or less of genu valgum was considered desirable. Average age at surgery was 14.7 years (range 7–25 years). Clinical follow-up is still ongoing, but averages 5.0 years (range 2 months to 18 years). Charts and radiographs were reviewed for complications, radiographic alignment, and surgical technique. The surgical procedure was customized to each patient’s deformity, consisting of the following steps:
  1. Complete proximal to distal surgical decompression of the peroneal nerve
  2. Radical release and mobilization of the severe quadriceps contracture and iliotibial band contracture
  3. Distal lateral hamstring lengthening/tenotomy and lateral collateral ligament release
  4. Proximal and distal realignment of the subluxed/dislocated patella, medial and lateral retinacular release, vastus medialis advancement, patellar chondroplasty, medial patellofemoral ligament plication, and distal patellar realignment by Roux-Goldthwait technique or patellar tendon transfer with tibial tubercle relocation
  5. Proximal tibial varus osteotomy with partial fibulectomy and anterior compartment release
  6. Occasionally, distal femoral osteotomy

Results

In all cases, the combination of radical soft-tissue release, patellar realignment and bony osteotomy resulted in 10° or less of genu valgum at the time of surgical correction. Complications of surgery included three patients (five limbs) with knee stiffness that was successfully manipulated, one peroneal nerve palsy, one wound slough and hematoma requiring a skin graft, and one pseudoarthrosis requiring removal of hardware and repeat fixation. At last follow-up, radiographic correction of no more than 20° of genu valgum was maintained in all but four patients (four limbs). Two patients (three limbs) had or currently require revision surgery due to recurrence of the deformity.

Conclusion

The operative approach presented in this study has resulted in correction of the severe genu valgum deformity in Ellis-van Creveld syndrome to 10° or less of genu valgum at the time of surgery. Although not an outcomes study, a correction of no more than 20° genu valgum has been maintained in many of the cases included in the study. Further clinical follow-up is still warranted.

Level of evidence

IV.  相似文献   
103.
104.
Accumulation of the transactive response DNA-binding protein 43 (TDP-43) is a major hallmark of several neurodegenerative disorders, collectively known as TDP-43 proteinopathies. The most common TDP-43 proteinopathies, frontotemporal lobar degeneration with TDP–43-positive inclusions, and amyotrophic lateral sclerosis, share overlapping neuropathological and clinical phenotypes. The development and detailed analysis of animal models of TDP-43 proteinopathies are critical for understanding the pathogenesis of these disorders. Transgenic mice overexpressing mutant human TDP-43 (herein referred to as hTDP-43) are characterized by neurodegeneration and reduced life span. However, little is known about the behavioral phenotype of these mice. Here we report the novel finding that hTDP-43 mice develop deficits in cognition, motor performance, and coordination. We show that these behavioral deficits are associated with the accumulation of nuclear and cytosolic TDP-43 C-terminal fragments, a decrease in endogenous TDP-43 levels, and synaptic loss. Our findings provide critical insights into disease pathology, and will help guide future preclinical studies aimed at testing the effects of potential therapeutic agents on the onset and progression of TDP-43 proteinopathies.  相似文献   
105.
IntroductionDolutegravir (DTG) has become a preferred component of first‐line antiretroviral therapy (ART) in many settings but may be associated with excess weight gain. We evaluated changes in weight and body mass index (BMI) after switch to single‐tablet tenofovir/lamivudine/dolutegravir (TLD) by people living with HIV (PLWH) in four African countries.MethodsThe African Cohort Study (AFRICOS) prospectively follows adults with and without HIV in Kenya, Uganda, Tanzania and Nigeria. Demographics, ART regimen, weight, BMI and waist‐to‐hip ratio were collected every 6 months. Multivariable Cox proportional hazards modelling was used to estimate hazard ratios and 95% confidence intervals (CIs) for factors associated with developing a BMI ≥25 kg/m2. Linear mixed effects models with random effects were used to examine the average change in BMI, weight and waist‐to‐hip ratio.ResultsFrom 23 January 2013 to 1 December 2020, 2950 PLWH were enrolled in AFRICOS and 1474 transitioned to TLD. In adjusted models, PLWH on TLD had 1.77 times the hazard of developing a high BMI (95% CI: 1.22–2.55) compared to PLWH on non‐TLD ART. Examining change in weight among all PLWH on ART, participants on TLD gained an average of 0.68 kg (95% CI: 0.32–1.04) more than PLWH on other regimens after adjusting for duration on ART, sex, age, study site and CD4 nadir. Among participants who switched to TLD, the average change in weight prior to TLD switch was 0.35 kg/year (95% CI: 0.25–0.46) and average change in weight was 1.46 kg/year (95% CI: 1.18–1.75) in the year following transition to TLD after adjustment for confounders.ConclusionsElevated BMI and weight gain among PLWH on TLD are concerning safety signals. Implications for the development of metabolic comorbidities should be monitored, particularly if annual weight gain persists during continued follow‐up after transitioning to TLD.  相似文献   
106.
Background: The COVID-19 pandemic has had a wide-reaching impact. Graduate medical education of orthopedic surgeons was not spared from the jarring changes. Purpose: We sought to survey fellowship program directors in the field of orthopedic surgery about how the COVID-19 pandemic affected the education of the 2019 to 2020 and 2020 to 2021 fellowship classes and the future of their programs. Methods: In October 2020, an 18-item survey was distributed by an official of the American Academy of Orthopedic Surgeons (AAOS) to the specialty societies that govern fellowship training. Each specialty society then distributed the survey to its respective program directors. A reminder email was sent during the enrollment period. Each respondent was able to complete the survey once. Survey questions were grouped into 3 sections: general information about the fellowship training programs, the impact of COVID-19 on the 2019 to 2020 fellowship class, and the future impact of COVID-19 on the fellowship training programs. Results: Of the 564 accredited orthopedic surgery fellowship programs in the United States, 190 directors responded. Of these, 73.59% reported COVID-19 had a negative impact on the 2019 to 2020 fellowship class. A normal distribution of responses was found regarding didactic and academic learning, research, and mentorship opportunities. A majority of respondents said they believe that there will be no negative impact on patient care the fellows provide in the years to come. Conclusion: Orthopedic surgery fellowship program directors acknowledged that while there were negative effects to training in the pandemic, they did not think these would negatively affect patient care provided by 2019 to 2020 fellows in the short and medium term. They also reported positive outcomes from the experience of the pandemic, including new ways to educate fellows.  相似文献   
107.
108.
Objective:To investigate the effects of 30-day treatment with therapeutic dose equivalent levels of tramadol on serum testosterone level, sperm parameters, and ...  相似文献   
109.
Bottle‐feeding is an infant feeding modality that has been in existence since ancient times, and currently, a significant number of infants are being fed via a bottle with either breastmilk or formula. Although research on bottle‐feeding has continued, it exists in fragmented, often small studies that focus on singular aspects of feeding an infant using a bottle, with limited information on the bottle‐feeding act. Systems theory was the approach used to define the act of bottle‐feeding and identify the parts within this act. Health databases were searched using MeSH terms. A summary of the studies are included. The findings of this review revealed that healthy term bottle‐feeding infants use similar tongue and jaw movements, can create suction and sequentially use teat compression to obtain milk, with minimal differences in oxygen saturation and SSB patterns, when compared with breastfeeding infants. Bottle and teat characteristics were revealed to affect infant feeding and milk intake. An infant's milk intake during feeding was shown to have a strong association with the interaction between the infant and parent/caregiver. With the issue of who controls the feed, mother or infant, likely to affect an infant's ability to self‐regulate their milk intake. Redefining bottle‐feeding as a holistic system identifies the interrelationship of the various parts which will improve the understanding of the reciprocal nature of infant feeding. To optimize bottle‐feeding outcomes, further research is required on parents' and health professionals' knowledge and understanding of the parts within the act of bottle‐feeding.  相似文献   
110.
Leukocytes contain within their lysosomal granules enzymatic activity that will generate from C5 chemotactic activity for leukocytes (neutrophils) and tumor (Walker carcinosarcoma) cells. Similar activity has been found in phagocytic supernatant fluids from neutrophils and in purified preparations of the leukocyte neutral proteases elastase and cathepsin G. White leukotactic activities can be generated from either the third (C3) or the fifth (C5) components of complement, only C5 serves as a source for generation of the chemotactic activity for tumor cells. As has been previously shown with trypsin, the C5-related chemotactic activities generated by leukocyte proteases are time-dependent: leukotactic activity appears early, then disappears, and is replaced by chemotactic activity for tumor cells. The generation of these chemotactic activities from C5 is blocked by prior treatment of leukocyte preparations with the neutral protease inhibitor Trasylol. The demonstration that enzyme activities from leukocytes have the ability to generate tumor cell chemotactic factors from C5 suggests a possible mechanism by which the development of metastatic lesions may be promoted at sites of tissue injury or inflammation.  相似文献   
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