Application and survival curve of total hip arthroplasties: a systematic comparative analysis using worldwide hip arthroplasty registers

Purpose

The aim of the study was to compare primary total hip arthroplasty (THA) implantations between different countries in terms of THA number per inhabitant, age, and procedure type and to compare the survival curve including all THAs using hip arthroplasty registers.

Methods

THA registers were compared between different countries with respect to the number of primary implantations per inhabitant and age, procedure type and survival curve. We performed a literature search for all national hip arthroplasty registers providing annual reports for 2009 or, if not available, a more recent period. The data from these reports were analysed in terms of number, age distribution and procedure type of primary THAs and survival curves.

Results

We identified nine hip arthroplasty registers, which comprised sufficient data to be included. A large variation was found in the annual number of primary THA implantations per inhabitant. The procedure type varied greatly as well, e.g. in Sweden 67 % are cemented THAs whereas in Emilia-Romagna (Italy) 89 % are cementless THAs.

Conclusions

This study revealed large differences in terms of the annual number of primary THAs per inhabitant and primary THA procedure type across countries. These data can be used to rank local primary THA implantations within an international context.     

Prognostic value of diffusion tensor imaging parameters in severe traumatic brain injury

Diffusion tensor imaging (DTI) has recently emerged as a useful tool for assessing traumatic brain injury (TBI). In this study, the prognostic value of the relationship between DTI measures and the clinical status of severe TBI patients, both at the time of magnetic resonance imaging (MRI), and their discharge to acute TBI rehabilitation, was assessed. Patients (n=59) admitted to the trauma center with severe closed head injuries were retrospectively evaluated after approval from the institution's institutional review board, to determine the prognostic value of DTI measures. The relationship of DTI measures, including apparent diffusion coefficient (ADC), fractional anisotropy (FA), axial (λ‖) and radial diffusivity (λ⊥) from the whole brain white matter, internal capsule, genu, splenium, and body of the corpus callosum, were compared with neurological status at MRI and at discharge to acute TBI rehabilitation. Whole brain white matter averages of ADC, λ‖, and λ⊥, and their coefficient of variation (CV) were significantly correlated with the Glasgow Coma Scale (GCS) score on the day of MRI. The average λ‖ was significantly correlated with GCS scores on the day of MRI in all measured brain regions. Outcomes were associated with whole brain white matter averages of ADC and λ‖, and the CVs of FA, ADC, λ‖, and λ⊥; and the averages and CVs of FA and λ‖ in all corpus callosum regions. The inclusion of regional and global DTI measures improved the accuracy of prognostic models, when adjusted for admission GCS score and age (p<0.05). Whole brain white matter and regional DTI measures are sensitive markers of TBI, and correlate with neurological status both at MRI and discharge to rehabilitation. The addition of DTI measures adjusted for age, gender, and admission GCS score significantly improved prognostic models.     

End-stage extension of the knee and its influence on tibial tuberosity-trochlear groove distance (TTTG) in asymptomatic volunteers

Purpose

Increased tibial tuberosity-trochlear groove distance (TTTG) is one potential correcting parameter in patients suffering from lateral patellar instability. It was hypothesized that end-stage extension of the knee might influence the TTTG distance on MR images.

Methods

Transverse T1-weighted MR images of the knee were acquired at full extension, 15° and 30° flexion of the knee in 30 asymptomatic volunteers. MRI parameters: slice thickness: 3 mm, matrix: 256 × 384, FOV: 150 × 150 mm. Two observers independently measured the TTTG at all positions.

Results

Mean TTTG for observer 1 was 15.1 ± 3.2 mm at full extension, 10.0 ± 3.5 mm at 15° flexion and 8.1 ± 3.4 mm at 30° flexion. Mean TTTG for observer 2: 14.8 ± 3.3 mm at full extension, 9.4 ± 3.0 mm at 15° flexion, 8.6 ± 3.4 mm at 30° flexion. Mean values were significantly different (p < 0.001) between full extension and 15° as well as 30° flexion for both observers. Mean values were significantly different (p < 0.001) between 15° and 30° for observer 1, but not for observer 2 (n.s.). Interobserver agreement was very good (intraclass correlation coefficient: 0.87–0.88; p < 0.001).

Conclusions

The TTTG increases significantly at the end-stage extension of the knee. Therefore, the comparability of published TTTG values measured on radiographs, CT and MRI at various flexion/extension angles of the knee are limited.

Level of evidence

Development of diagnostic criteria in a consecutive series of patients and a universally applied ‘gold’ standard, Level II.     

Vertebral body stapling procedure for the treatment of scoliosis in the growing child

Thirty-nine consecutive patients have had vertebral body stapling of 52 curves (26 patients with one curve stapled and 13 with two). For the group with patients who were 8 years or older with less than 50 degrees preoperative curve and a minimum 1-year followup, coronal curve stability was 87% when defined by progression less than or equal to 10 degrees . Fusion was necessary in two patients. No curves less than 30 degrees at the time of stapling progressed greater than or equal to 10 degrees . Major complications occurred in one patient (2.6%, diaphragmatic hernia) and minor complications occurred in five patients (13%). Further followup of the patient cohort and further research into efficacy and indications are warranted.     

Nicht adjustierbare Bänder zur Therapie der männlichen Belastungsharninkontinenz

Even though the artificial sphincter is still the treatment of choice in the surgical therapy of male stress urinary incontinence, recent developments have introduced numerous minimally invasive treatment options with acceptable clinical results. The male slings have been included into the EAU guidelines for treatment of male stress urinary incontinence. A distinct choice of patients and treatment options will lead to the highest chance of success. Besides the adjustable compressive slings, the non-adjustable and non-compressive AdVance® Sling offers a possible option for a functional approach to treatmentratio. A critical assessment of all these methods remains essential and prospective randomized trials are still missing.     

A Comparison of FES with KAFO for Providing Ambulation and Upright Mobility in a Child with a Complete Thoracic Spinal Cord Injury

Abstract

This study compared functional and physiologic measures of ambulation and upright mobility with functional electrical stimulation (FES) versus knee-ankle-foot-orthoses (KAFO) in an 11-year-old boy with a T-10 level spin.il cord injury. The child was a limited community ambulator with bilateral KAFO and loftstrand crutches. The FES system consisted of percutaneous intramuscular electrodes controlled by a portable stimulator and thumbswitch, an AFO for ankle and foot support, and loftstrand crutches. The subject used a swing-through gait pattern with both modes of mobility. The Functional Independence Measure scoring system and time to completion were used to compare performance in 6 standardized activities: donning, high transfer, inaccessible toilet transfer, ascend/descend stairs, and floor-to-standing transfer. Ten repeated measures were performed for each mode. Physiologic measures included energy expenditure, postural stability using forceplates, and a Functional Standing Test (FST). The subject performed all 6 mobility activities independently with FES and KAFO. In 4 of 6 activities, there was a trend toward faster times with FES, but this was not statistically significant. Toilet transfers and stair descent were performed significantly faster with KAFO. There was no difference in completion times on the activities of the FST. Measures of postural sway suggested that the subject was more stable with KAFO during quiet standing, while the modes were equal during a dynamic activity (raising arm for functional use). Energy expenditure results revealed no significant difference in oxygen cost per meter but a significantly higher oxygen consumption rate per minute for FES. Ambulation with both modes was performed at levels consistent with strenuous exercise. Maximum ambulation distances were relatively equal while the subject’s velocity was significantly faster with FES. Of note, the subject reported ceasing ambulation during maximum distance trials due to general fatigue when using FES and due to shoulder pain with KAFO ambulation. For this subject, FES provided a means of performing upright mobility tasks independently, comparable with that of KAFO, while providing a faster ambulation velocity and a potential means of cardiovascular training.     

Conserved quaternary structure of ligand-gated ion channels: the postsynaptic glycine receptor is a pentamer.

The postsynaptic glycine receptor of rat spinal cord is a glycosylated membrane protein that, after affinity purification, contains membrane-spanning subunits of Mr 48,000 and 58,000 and an associated peripheral polypeptide of Mr 93,000. Here, the quaternary structure of the transmembrane core of the receptor was investigated by chemically crosslinking its subunits. Upon treatment with crosslinking reagents of different side-chain specificities and lengths, a consistent set of adducts up to Mr 260,000 was detected after separation by NaDodSO4/PAGE. The observed pattern of adducts was similar irrespective of whether purified receptor protein or synaptosomal membranes were crosslinked. Compositional analysis revealed that the crosslinked adducts contained the Mr 48,000 and 58,000 subunits in varying ratios but not the peripheral Mr 93,000 polypeptide. Thus adducts of intermediate molecular weight represent dimers, trimers, and tetramers of the transmembrane subunits, whereas the major adduct of Mr 260,000 corresponds to a pentameric assembly of subunits forming the ion channel of the glycine receptor. This subunit arrangement is similar to that reported for the nicotinic acetylcholine receptor of fish electric organ and skeletal muscle. Hence, we suggest that the different ligand-gated ion channels of excitable membranes share a similar quaternary structure.