Is Bilateral Total Knee Arthroplasty Staged at a One-Week Interval Safe? A Matched Case Control Study

Controversy surrounds the safety of bilateral total knee arthroplasty (TKA) and whether staging the procedures one week apart represents a safer option. A consecutive series of 234 patients underwent either a simultaneous (103 patients) or staged bilateral TKA (131 patients) from 2007 to 2012 and were compared to a matched control group of unilateral TKA (131 patients). Staged patients had no difference in one-year complication rate when compared to simultaneous bilateral TKA and the matched unilateral TKA control group (15% vs. 19% vs. 15%, P = 0.512). There was also no difference in perioperative complications (10% vs. 14% vs. 7%, P = 0.231) or 90-day readmissions (8% vs. 4% vs. 4%, P = 0.295). In selected patients with bilateral knee OA, TKA staged at a one-week interval is a safe alternative.     

Advanced multiplicity adjustment methods in clinical trials

During the last decade, many novel approaches for addressing multiplicity problems arising in clinical trials have been introduced in the literature. These approaches provide great flexibility in addressing given clinical trial objectives and yet maintain strong control of the familywise error rate. In this tutorial article, we review multiple testing strategies that are related to the following: (a) recycling local significance levels to test hierarchically ordered hypotheses; (b) adapting the significance level for testing a hypothesis to the findings of testing previous hypotheses within a given test sequence, also in view of certain consistency requirements; (c) grouping hypotheses into hierarchical families of hypotheses along with recycling the significance level between those families; and (d) graphical methods that permit repeated recycling of the significance level. These four different methodologies are related to each other, and we point out some connections as we describe and illustrate them. By contrasting the main features of these approaches, our objective is to help practicing statisticians to select an appropriate method for their applications. In this regard, we discuss how to apply some of these strategies to clinical trial settings and provide algorithms to calculate critical values and adjusted p‐values for their use in practice. The methods are illustrated with several numerical examples. Copyright © 2013 John Wiley & Sons, Ltd.     

Acute lymphoblastic leukemia presenting with limping in a young adult

Acute lymphoblastic leukemia is one of the rare malignancies in adult. We report a 29‐year‐old man presented with progressive limping followed a chronic back pain. Imaging showed reduced vertebral body height and diffuse lytic skeletal infiltration. Bone marrow aspiration confirmed B‐acute lymphoblastic leukemia/lymphoma, and the patient was treated with chemotherapy.     

Utilizing the McGill Thyroid Nodule Score to compare between hemithyroidectomy cases who required completion thyroidectomy and cases of hemithyroidectomy alone

ObjectivesThis study aims to evaluate whether the McGill Thyroid Nodule Score (MTNS) accurately helps to decide the extent of surgery (hemithyroidectomy versus total thyroidectomy) based on the malignancy risk and to assess whether its use lowers the rate of completion thyroidectomy in cases of indeterminate thyroid nodules.MethodsWe performed a retrospective cohort study comparing MTNS results of patients undergoing hemithyroidectomy in King Abdulaziz Medical City, NGHA, Jeddah from the period of January 2013 to December 2017. We divided the cases into hemithyroidectomy who required completion and hemithyroidectomy who did not need completion surgery. The pre-operative indeterminate FNA biopsy subgroup comprised of Bethesda type III (atypia of undetermined significance/follicular lesion of undetermined significance) and Bethesda type IV (follicular neoplasm/suspicious for a follicular neoplasm/Hurthle cell neoplasm). Post-operative histopathology was divided into benign or malignant groups.ResultsOf the 501 patient charts reviewed, 111 (22.2%) had an indeterminate FNA biopsy. 97 (87.4%) patients were females and 14 (12.6%) were males. In the hemithyroidectomy group, the pre-operative mean of the MTNS was 6.65, while in the completion thyroidectomy the mean was 11.47. The median MTNS was 7 (32% risk of malignancy) for the hemithyroidectomy group and 11 (63% risk of malignancy) for the completion thyroidectomy group (p < 0.001).ConclusionsBased on the MTNS the risk of malignancy in cases of hemithyroidectomy who required completion surgery was significantly higher than those who underwent hemithyroidectomy only. The MTNS can be of value to thyroid surgeon in the pre-operative decision-making when dealing with an indeterminate thyroid nodule on FNA biopsy.     

Pheochromocytoma presenting with severe abdominal pain and abnormal liver enzymes

Pheochromocytoma can present with right hypochondrial pain, elevated liver enzymes, and a misleading appearance on ultrasound scan mimicking hepatic mass due to the proximity of adrenal masses to the liver.     

Magnetic resonance imaging of mouse spinal cord.

The feasibility of performing high-resolution in vivo MRI on mouse spinal cord (SC) at 9.4 T magnetic field strength is demonstrated. The MR properties of the cord tissue were measured and the characteristics of water diffusion in the SC were quantified. The data indicate that the differences in the proton density (PD) and transverse relaxation time between gray matter (GM) and white matter (WM) dominate the contrast seen on the mouse SC images at 9.4 T. However, on heavily T(2)-weighted images these differences result in a reversal of contrast. The diffusion of water in the cord is anisotropic, but the WM exhibits greater anisotropy and principal diffusivity than the GM. The quantitative data presented here should establish a standard for comparing similar measurements obtained from the SCs of genetically engineered mouse or mouse models of SC injury (SCI).     

Magnetic resonance angiography of rat spinal cord at 9.4 T: a feasibility study.

In this study we investigated the feasibility of performing 3D time-of-flight magnetic resonance angiography to remotely image the arteries of rat spinal cord. Using a custom-designed implantable radiofrequency coil, we acquired angiograms from normal and injured cords. The potential of the approach was evaluated in terms of longitudinally monitoring the vascular reorganization of spinal cord following an injury.     

Use of pelvic incidence as a guide to reduction of H-type spino-pelvic dissociation injuries

OBJECTIVE: Describe the use of a radiographic parameter (pelvic incidence) to assess the sagittal plane reduction of H-type sacral fractures associated with spinopelvic dissociation, and assess the relationship between standing lumbar lordosis to pelvic incidence after spinopelvic dissociation. DESIGN: Retrospective radiographic and clinical review of treatment outcomes for patients with spinopelvic dissociation injuries secondary to H-type sacral fractures. SETTING: Level I Trauma Center. INTERVENTION: Pelvic incidence (PI), a radiographic parameter that measures the orientation of the lumbar spine relative to the pelvis, has been shown to have a correlation with the adequacy of surgical reduction as well as the risk of progression of high-grade spondylolisthesis. We used this parameter as a measure of sagittal plane reduction of spinopelvic dissociation injuries. PATIENTS/PARTICIPANTS: The clinical records and radiographs of five patients with spinopelvic dissociation injuries were reviewed. MAIN OUTCOME MEASUREMENTS: Radiographic measurements included standing PI and lumbar lordosis (LL). The relationship of lumbar lordosis on pelvic incidence was tested by a regression analysis. Clinical outcome was assessed by the self-reported ability of the patient to comfortably maintain an upright stance. RESULTS: The average follow-up period was 32 (range: 12-53) months. The average final PI was 82 (60-115) degrees. The average final lumbar lordosis was 58.2 (42-77) degrees. LL was found to be significantly related to PI (P<0.05). One patient with an abnormally high PI had lumbar fatigue with persistent stance. CONCLUSIONS: Pelvic incidence is a potentially useful radiographic parameter that can be used to assess the adequacy of sagittal plane reduction in patients with spinopelvic dissociation injuries.