Scapholunate Kinematics After Combined Palmar and Dorsal Ligament Reconstruction: A Quantitative Evaluation Using Four-Dimensional Computed Tomography.

Purpose: This observational pilot study investigated (1) carpal positioning in the neutral wrist pose, (2) the scapholunate (SL) rotation axis, (3) physiological SL motion, and (4) the SL distance after combined palmar and dorsal SL ligament reconstruction using quantitative four-dimensional computed tomography (4D-CT) imaging.

Methods: Six subjects were included, and 4D-CT images of both wrists were obtained. Kinematic parameters of the treated side were compared to those of the healthy contralateral side, which was used as the normal reference.

Patient-specific scaphoid prosthesis: surgical technique.

The scaphoid bone is essential for wrist stability, force transmission, and movement, being crucial for maintaining carpal kinematics. In cases where the scaphoid is non-reconstructable, a complete replacement can serve as a treatment option to preserve carpal alignment and motion. This approach has evolved since its first descriptions in 1945, benefiting significantly from advancements in patient-specific implant design, additive manufacturing/3D printing, and material use in recent years.

Bilateral symmetry assessment of healthy forearm kinematics using 4D-CT.

Advanced stage distal radio-ulnar joint (DRUJ) injury may warrant radius corrective osteotomy or arthroplasty. These procedures aim to restore geometry, function and kinematics and could benefit from preoperative planning where the contralateral forearm is typically used as reference. Natural variations regarding geometry and function between forearms are known but kinematic differences are not.

Complete absence of GLUT1 does not impair human terminal erythroid differentiation.

The glucose transporter 1 (GLUT1) is 1 of the most abundant proteins within the erythrocyte membrane and is required for glucose and dehydroascorbic acid (vitamin C precursor) transport. It is widely recognized as a key protein for red cell structure, function, and metabolism. Previous reports highlighted the importance of GLUT1 activity within these uniquely glycolysis-dependent cells, in particular for increasing antioxidant capacity needed to avoid irreversible damage from oxidative stress in humans.

Assessment of bone marrow edema on dual-energy CT scans in people with diabetes mellitus and suspected Charcot neuro-osteoarthropathy.

Objective: This study aimed to quantitatively assess the diagnostic value of bone marrow edema (BME) detection on virtual non-calcium (VNCa) images calculated from dual-energy CT (DECT) in people with diabetes mellitus and suspected Charcot neuro-osteoarthropathy (CN).

Materials And Methods: People with diabetes mellitus and suspected CN who underwent DECT of the feet (80kVp/Sn150kVp) were included retrospectively. Two blinded observers independently measured CT values on VNCa images using circular regions of interest in five locations in the midfoot (cuneiforms, cuboid and navicular) and the calcaneus of the contralateral or (if one foot was available) the ipsilateral foot.

Non-invasive quantitative assessment of induced component displacement can safely and accurately diagnose tibial component loosening in patients: A prospective diagnostic study.

Purpose: Aseptic loosening often requires major, expensive and invasive revision surgery. Current diagnostic modalities merely show indirect signs of loosening. A recent proof of concept study proposed a non-invasive technique for the quantitative and visual assessment of implant movement as a diagnostic aid for tibial component loosening.

A three-dimensional algorithm for precise measurement of human auricle parameters.

Measurement of auricle parameters for planning and post-operative evaluation presents substantial challenges due to the complex 3D structure of the human auricle. Traditional measurement methods rely on manual techniques, resulting in limited precision. This study introduces a novel automated surface-based three-dimensional measurement method for quantifying human auricle parameters.

Minimal but potentially clinically relevant anteroinferior position of the humeral head following traumatic anterior shoulder dislocations: A 3D-CT analysis.

In unstable shoulders, excessive anteroinferior position of the humeral head relative to the glenoid can lead to a dislocation. Measuring humeral head position could therefore be valuable in quantifying shoulder laxity. The aim of this study was to measure (1) position of the humeral head relative to the glenoid and (2) joint space thickness during passive motion in unstable shoulders caused by traumatic anterior dislocations and in contralateral uninjured shoulders.

Performance of the Aptis Distal Radioulnar Joint Implant: A Clinical Case Series Including Four-Dimensional Computed Tomography Kinematic Analysis.

High complication rates and surgical revision rates following Aptis implant placement have been reported in the literature. This study evaluates the performance of the Aptis implant of twelve patients using four-dimensional kinematic analysis. The (mean) follow-up was 58 months.

Promising results of an non-invasive measurement of knee implant loosening using a loading device, CT-scans and 3D image analysis.

Background: After total knee arthroplasty up to 13% requires revision surgery to address loosening. No current diagnostic modalities have a sensitivity or specificity higher than 70-80% to detect loosening, leading to 20-30% of patients undergoing unnecessary, risky and expensive revision surgery. A reliable imaging modality is required to diagnose loosening.

Kinematic analysis of forearm rotation using four-dimensional computed tomography.

This study aimed to quantify forearm kinematics with a focus on the forearm rotation axis. Ten healthy volunteers were included in the study. One three-dimensional computed tomographic scan and two four-dimensional computed tomographic scans were done in all the arms to capture forearm joint motion.

Weight-bearing cone-beam CT: the need for standardised acquisition protocols and measurements to fulfill high expectations-a review of the literature.

Weight bearing CT (WBCT) of the lower extremity is gaining momentum in evaluation of the foot/ankle and knee. A growing number of international studies use WBCT, which is promising for improving our understanding of anatomy and biomechanics during natural loading of the lower extremity. However, we believe there is risk of excessive enthusiasm for WBCT leading to premature application of the technique, before sufficiently robust protocols are in place e.

Functional bracing in distal radius fractures: a cadaveric pilot study.

Background: Extra-articular distal radius fractures are often treated by circular casting. A functional brace, however, may equally support the fracture zone but allows early mobilization of the radiocarpal joint. Since the amount of fracture movement for different types of fixation is currently unknown, a study was initiated to investigate the degree of bone displacement in extra-articular distal radius fractures fixated by regular circular casting, functional bracing, or no-fixation.

The Amsterdam Foot Model: a clinically informed multi-segment foot model developed to minimize measurement errors in foot kinematics.

Background: Foot and ankle joint kinematics are measured during clinical gait analyses with marker-based multi-segment foot models. To improve on existing models, measurement errors due to soft tissue artifacts (STAs) and marker misplacements should be reduced. Therefore, the aim of this study is to define a clinically informed, universally applicable multi-segment foot model, which is developed to minimize these measurement errors.

Lower leg symmetry: a Q3D-CT analysis.

Purpose: In fracture and realignment surgery, the contralateral unaffected side is often used as a model or template for the injured bone even though clinically valuable quantitative data of bilateral symmetry are often unavailable. Therefore, the objective of the present study was to quantify and present the bilateral symmetry of the tibia and fibula.

Methods: Twenty bilateral lower-leg CT scans were acquired in healthy volunteers.

Biomechanical and musculoskeletal changes after flexor tenotomy to reduce the risk of diabetic neuropathic toe ulcer recurrence.

Objective: To assess the effect of flexor tenotomy in patients with diabetes on barefoot plantar pressure, toe joint angles and ulcer recurrence during patient follow-up.

Methods: Patients with a history of ulceration on the toe apex were included. They underwent minimally invasive needle flexor tenotomy by an experienced musculoskeletal surgeon.

Four-dimensional CT analysis of carpal kinematics: An explorative study on the effect of sex and hand-dominance.

Wrist pathology is often diagnosed by using the contralateral wrist as a comparison of baseline motion and strength. However, recent range of motion studies suggest that females have different carpal motion patterns compared to males and that the dominant carpal bones have different motion patterns. The purpose of this study is to evaluate the effect of sex and hand dominance on in vivo kinematics of the scaphoid, lunate and capitate using four-dimensional computed tomography (4D-CT) analysis in healthy uninjured volunteers.

Validation of Noninvasive Epicardial and Endocardial Repolarization Mapping.

The detection and localization of electrophysiological substrates currently involve invasive cardiac mapping. Electrocardiographic imaging (ECGI) using the equivalent dipole layer (EDL) method allows the noninvasive estimation of endocardial and epicardial activation and repolarization times (AT and RT), but the RT validation is limited to studies. We aimed to assess the temporal and spatial accuracy of the EDL method in reconstructing the RTs from the surface ECG under physiological circumstances and situations with artificially induced increased repolarization heterogeneity.

Comparison of an oblique single cut rotation osteotomy with a novel 3D computer-assisted oblique double cut alignment approach.

An oblique double-cut rotation osteotomy (ODCRO) enables correcting a complex bone deformation by aligning, in 3D, the distal, middle and proximal bone segments with a target bone, without intersegmental gaps. We propose virtual preoperative planning of an ODCRO. To minimize a residual translation error, we use an optimization algorithm and optimize towards bone length, alignment in the transverse direction, or a balanced reconstruction.

Madelung Deformity: Radioscapholunate Arthrodesis With a Neo-DRUJ.

Background: Madelung deformity is a rare wrist anomaly that causes considerable pain while restricting function. In this study, we describe a radioscapholunate (RSL) arthrodesis with a neo-distal radioulnar joint (DRUJ) in Madelung deformity patients with an abnormal sigmoid notch and compare results to patients after a reverse wedge osteotomy.

Methods: Six wrists underwent RSL arthrodesis with a neo-DRUJ in a two-phase approach: (1) modified RSL arthrodesis with triquetrectomy; and (2) distal scaphoidectomy.

The Effect of Roux-en-Y Gastric Bypass on Bone Marrow Adipose Tissue and Bone Mineral Density in Postmenopausal, Nondiabetic Women.

Objectives: This study aimed to determine the effect of bariatric surgery-induced weight loss on bone marrow adipose tissue (BMAT) and bone mineral density (BMD) in postmenopausal, nondiabetic women.

Methods: A total of 14 postmenopausal, nondiabetic women with obesity who were scheduled for laparoscopic Roux-en-Y gastric bypass surgery (RYGB) were included in this study. Vertebral bone marrow fat signal fraction was determined by quantitative chemical shift magnetic resonance imaging, and vertebral volumetric BMD (vBMD) was determined by quantitative computed tomography before surgery and 3 and 12 months after surgery.