The Relationship Between Arthroplasty Surgeons' Experience Level and Optimal Cable Tensioning in the Fixation of Extended Trochanteric Osteotomy.

Introduction: In this study, our aim was to examine the relationship between the arthroplasty surgeons' experience level and their aptitude to adjust the cable tension to the value recommended by the manufacturer when asked to provide fixation with cables in artificial bones that underwent extended trochanteric osteotomy (ETO).

Materials And Methods: A custom-made cable tensioning device with a microvoltmeter was used to measure the tension values in Newtons (N). An ETO was performed on 4 artificial femur bones.

Knotless anchors offer better prevention of meniscal excursion than knotted anchors: An experimental study of the bovine knee.

Objective: Due to the biomechanical importance of the meniscal root ligament, several surgical techniques have been defined in order to treat meniscal root tear. Different application techniques have different levels of difficulty. We aimed to find a stronger and simpler repair technique.

3D printed poly(ε-caprolactone) scaffolds modified with hydroxyapatite and poly(propylene fumarate) and their effects on the healing of rabbit femur defects.

A large variety of approaches have been used to treat large and irregular shaped bone defects with less than optimal success due to material or design issues. In recent years patient specific constructs prepared by additive manufacturing provided a solution to the need for shaping implants to fit irregular defects in the surgery theater. In this study, cylindrical disks of poly(ε-caprolactone) (PCL) were printed by fused deposition modeling and modified with nanohydroxyapatite (HAp) and poly(propylene fumarate) (PPF) to create a mechanically strong implant with well-defined pore size and porosity, controllable surface hydrophilicity (with PPF) and osteoconductivity (with HAp).

Non-integer viscoelastic constitutive law to model soft biological tissues to in-vivo indentation.

Purpose: During the last decades, derivatives and integrals of non-integer orders are being more commonly used for the description of constitutive behavior of various viscoelastic materials including soft biological tissues. Compared to integer order constitutive relations, non-integer order viscoelastic material models of soft biological tissues are capable of capturing a wider range of viscoelastic behavior obtained from experiments. Although integer order models may yield comparably accurate results, non-integer order material models have less number of parameters to be identified in addition to description of an intermediate material that can monotonically and continuously be adjusted in between an ideal elastic solid and an ideal viscous fluid.

Mechanical design, analysis, and laboratory testing of a dental implant with axial flexibility similar to natural tooth with periodontal ligament.

At the interface between the jawbone and the roots of natural teeth, a thin, elastic, shock-absorbing tissue, called the periodontal ligament, forms a cushion which provides certain flexibility under mechanical loading. The dental restorations supported by implants, however, involve comparatively rigid connections to the jawbone. This causes overloading of the implant while bearing functional loading together with neighboring natural teeth, which leads to high stresses within the implant system and in the jawbone.

Impact of fibular torsion and rotation on chronic ankle instability.

Background: The fibula is known not to involve in transmission of weight but known simply as an ankle stabilizer. However, its main function in stabilizing the ankle remains obscure. Since the fibula has an impact on torsion and rotation of the ankle, its effect on lateral ankle instability should be investigated.

Predicting bone remodeling around tissue- and bone-level dental implants used in reduced bone width.

The objective of this study was to predict time-dependent bone remodeling around tissue- and bone-level dental implants used in patients with reduced bone width. The remodeling of bone around titanium tissue-level, and titanium and titanium-zirconium alloy bone-level implants was studied under 100 N oblique load for one month by implementing the Stanford theory into three-dimensional finite element models. Maximum principal stress, minimum principal stress, and strain energy density in peri-implant bone and displacement in x- and y- axes of the implant were evaluated.

Effects of custom-made insole on gait pattern of patients with unilateral displaced intra-articular calcaneal fracture: evaluation with computerized gait analysis.

Objective: The aim of this study was to investigate whether use of custom-fabricated insoles improves the gait pattern in patients with displaced intra-articular calcaneal fractures.

Methods: Fourteen patients (7 female, 7 male; mean age: 39 ± 12 years) and 11 healthy individuals (mean age: 42 ± 13 years) were included in the study. Treatment protocol included conservative treatment involving immobilization, with or without closed reduction, active exercises, wear of a custom-fabricated insole and prospective follow-up.

Ankle clonus and its relationship with the medium-latency reflex response of the soleus by peroneal nerve stimulation.

Ankle clonus and soleus medium-latency reflex are stretch-induced responses. Clonus is traditionally considered to be the result of oscillation in the group Ia mediated spinal stretch reflex but the soleus medium-latency reflex response originates mainly from the activation of group II afferents. The medium latency reflex response (MLR) was recorded in soleus muscle by peroneal nerve stimulation and clonus beats were recorded in soleus muscle using EMG in 19 spastic patients.

Numeric simulation of time-dependent remodeling of bone around loaded oral implants.

Purpose: The objective of this study was to investigate the time-dependent biomechanics of marginal bone around osseointegrated dental implants within physiologic loading conditions.

Materials And Methods: The remodeling of marginal bone around a 4.1-mm-diameter, 10-mm-long implant was studied by implementing the Stanford theory into axisymmetric mathematical models simulating different bone support at the implant neck: 1-mm-thick cortical bone (model 1), 0.

Predicting time-dependent remodeling of bone around immediately loaded dental implants with different designs.

The purpose of this study was to predict time-dependent biomechanics of bone around cylindrical screw dental implants with different macrogeometric designs under simulated immediate loading condition. The remodeling of bone around a parallel-sided and a tapered dental implant of same length was studied under 100N oblique load by implementing the Stanford theory into three-dimensional finite element models. The results of the analyses were examined in five time intervals consisting loading immediately after implant placement, and after 1, 2, 3 and 4 weeks following implantation.

Axial rotation and mediolateral translation of the fibula during passive plantarflexion.

Background: Since the fibula is linked to the ankle as well as the knee joint, its importance for knee and ankle disabilities should be investigated. This study evaluates its movement during range of motion of the ankle.

Materials And Methods: An instrument, together with the experimental protocol, was devised to determine the relative motion of the fibula in reference to the tibia with motion of the ankle joint on 20 paired lower extremity cadaver specimens.

Numerical study of the aerodynamic effects of septoplasty and partial lateral turbinectomy.

Objectives: To investigate, first, the effects of septal deviation and concha bullosa on nasal airflow, and second, the aerodynamic changes induced by septoplasty and partial lateral turbinectomy, using computational fluid dynamics (CFD).

Methods: A three-dimensional model of a nasal cavity was generated using paranasal sinus computed tomography images of a cadaver with concha bullosa and septal deviation. Virtual septoplasty and partial lateral turbinectomy were performed on this model to generate a second model representing the postoperative anatomy.

Dynamic function of the fibula. Gait analysis evaluation of three different parts of the shank after fibulectomy: proximal, middle and distal.

The purpose of this case study was to investigate the dynamic features of fibular movement to gait pattern by analyzing the gait of individuals with three different parts of the fibula resected. Gait analyses revealed that proximal fibula resection impaired knee stability, whereas distal fibula resection disturbed ankle kinematics significantly. Except a mild secondary quadriceps weakness, middle fibula resection did not cause a significant biomechanical disturbance on gait.

The annular ligament: an anatomical study.

Background: Despite documentations of ligamentous structures of the elbow, the anatomy and clinical and functional importance of the annular ligament has not been comprehensively defined in the orthopaedic literature.

Hypothesis: The annular ligament is an important component of both the proximal radioulnar and humeroradial joints, as well as an important component of the neighboring muscles and ligaments.

Study Design: Descriptive laboratory study.

Functional evaluation of intraarticular severely comminuted fractures of the calcaneus with gait analysis.

Twenty-one patients (23 feet) treated nonsurgically for severely comminuted intraarticular fractures of the calcaneus were evaluated prospectively with a clinical scoring scale and computerized gait analysis. All patients had Sanders type III and type IV fractures. The treatment protocol consisted of no closed reduction, immobilization in removable splint, physiotherapy after edema subsided, and weightbearing after 8 weeks.

Accuracy of a manual torque application device for morse-taper implants: a technical note.

Purpose: The objective of this study was to compare torques applied by new and used manual torque devices for Morse-taper implants.

Material And Methods: Fifteen ITI manual torque devices were tested. Those in group 1 (n = 5) were new (ie, never used), those in group 2 (n = 5) had been used 50 to 200 times, and those in group 3 (n = 5) had been used 500 to 1,000 times.

Nonlinear viscoelastic material property estimation of lower extremity residual limb tissues.

Axisymmetric nonlinear finite-element analysis was used to simulate force-relaxation and creep data obtained during in vivo indentation of the residual limb soft tissues of six individuals with trans-tibial amputation [1]. The finite-element models facilitated estimation of an appropriate set of nonlinear viscoelastic material coefficients of extended James-Green-Simpson material formulation for bulk soft tissue at discrete, clinically relevant test locations. The results indicate that over 90% of the experimental data can be simulated using the two-term viscoelastic Prony series extension of James-Green-Simpson material formulation.

An anatomical study of the meniscofibular ligament.

We examined the anatomical structure of a ligament (ligamentum meniscofibulare) between apex fibulae and lateral meniscus by macroscopic and microscopic dissection and transillumination method in 50 knees of 25 cadavers (5 were fresh). We analyzed the function of this ligament, which runs between the head of the fibulae and lateral meniscus. The existence of a connection between knee joint and proximal tibiofibular joint was demonstrated by injecting colored liquid into the knee joint space and transillumination.

Nonlinear elastic material property estimation of lower extremity residual limb tissues.

The interface stresses between the residual limb and prosthetic socket have been studied to investigate prosthetic fit. Finite-element models of the residual limb-prosthetic socket interface facilitate investigation of the mechanical interface and may serve as a potential tool for future prosthetic socket design. However, the success of such residual limb models to date has been limited, in large part due to inadequate material formulations used to approximate the mechanical behavior of residual limb soft tissues.