The biomechanical effect of injury and repair of the inferior glenohumeral ligament on glenohumeral stability: Contribution of the posterior band.

Background: Many surgical procedures are proposed to manage shoulder instability with recurrent dislocation but there is still a high rate of failure or complications. Repairs are often limited to anterior part of inferior glenohumeral ligament but some authors are reporting better clinical results if its posterior band is also repaired. This biomechanical study aimed to investigate the impact of a supplementary posterior injury compared with an isolated anterior injury and to analyze the contribution of a posterior repair of the inferior glenohumeral ligament compared with an isolated anterior repair.

Upper limb kinematics after Latissimus Dorsi transfer in children with brachial plexus birth palsy.

Background: Brachial plexus birth palsy remains a frequent condition and one of its treatments is to transfer the Latissimus Dorsi tendon to the infraspinatus muscle. The aim of this study was to analyse, for the first time, the three-dimensional kinematic effects of this operation on the upper limb joints during the five Mallet tasks and their correlation with clinical parameters.

Methods: Kinematic analysis was performed using an electromagnetic device.

De novo generation in an in vivo rat model and biomechanical characterization of autologous transplants for ligament and tendon reconstruction.

Background: Surgical reconstruction of ligaments and tendons is frequently required in clinical practice. The commonly used autografts, allografts, or synthetic transplants present limitations in terms of availability, biocompatibility, cost, and mechanical properties that tissue bioengineering aims to overcome. It classically combines an exogenous extracellular matrix with cells, but this approach remains complex and expensive.

Shoulder and elbow kinematics during the Mallet score in obstetrical brachial plexus palsy.

Background: The physical signs of obstetrical brachial plexus palsy range from temporary upper-limb dysfunction to a lifelong impairment and deformity in one arm. The aim of this study was to analyze the kinematics of the upper limb and to evaluate the contribution of glenohumeral and scapulothoracic joints of obstetrical brachial plexus palsy children.

Methods: Six children participated in this study: 2 males and 4 females with a mean age of 11.

Biomechanical Comparison of Locking Compression Plate and Limited Contact Dynamic Compression Plate Combined with an Intramedullary Rod in a Canine Femoral Fracture-Gap Model.

Objective: To compare the biomechanical properties of locking compression plate (LCP) and a limited contact dynamic compression plate combined with an intramedullary rod (LC-DCP-R) in a cadaveric, canine, femoral fracture-gap model.

Study Design: In vitro biomechanical study; nonrandomized, complete block (dog).

Sample Population: Paired cadaveric canine femora (n = 10 dogs).

Abrasive properties of braided polyblend sutures in cuff tendon repair: an in vitro biomechanical study exploring regular and tape sutures.

Purpose: This study aimed to evaluate the abrasive properties of different suture materials (tape or regular) on the infraspinatus tendon of sheep.

Methods: Four types of sutures were compared: FiberWire (Arthex, Naples FL), FiberTape (Arthrex), Orthocord (DePuy Mitek, Raynham, MA) and ForceFiber (Tornier, Bloomington, MN). Each suture (n = 10) was cycled with a filxed load of 10 N and an alternating motion of the suture through sheep infraspinatus tendon, with an excursion of 30 mm.

Bankart repair versus Bankart repair plus remplissage: an in vitro biomechanical comparative study.

Purpose: To biomechanically compare Bankart lesion repair alone and Bankart lesion repair associated with infraspinatus capsulotenodesis described as «remplissage», in the treatment of combined Bankart and Hill-Sachs lesions.

Methods: Seven pairs (right and left) of cadaveric shoulders have been tested, first without any lesion and then after performing a combined Bankart and Hill-Sachs lesions. For each pair, the specimens were then randomly assigned for Bankart lesion repair alone on one side or for Bankart lesion repair associated with remplissage on the other side.

Assessment of upper limb function in young Friedreich ataxia patients compared to control subjects using a new three-dimensional kinematic protocol.

Background: The assessment of Friedreich ataxia effects on upper limb function in clinical follow-up remains a challenging issue. To complete the usual clinical scales, an upper limb kinematic protocol adapted to Friedreich ataxia children and young adults has been developed and applied to both patients and control subjects.

Methods: Nineteen Friedreich ataxia patients (7-24 years old) and fifteen healthy controls (9-24) were examined twice during three tasks (drawing, pointing, pro-supination) inspired from the "International Cooperative Ataxia Rating Scale".

Upper limb motion analysis in children with hemiplegic cerebral palsy: proximal kinematic changes after distal botulinum toxin or surgical treatments.

Purpose: The purpose of this study is to describe the kinematic changes in children with cerebral palsy (CP) after treatments performed on the forearm, wrist or thumb, with specific attention to the changes around the trunk, shoulder and elbow kinematics.

Methods: With the use of a specific kinematic protocol, we first described the upper limb kinematics in a group of 27 hemiplegic patients during two simple daily tasks. Eight of these children were treated with botulinum toxin (Botox(®), Allergan) injection or surgery and were, thereafter, evaluated with another kinematic analysis in order to compare the pre- and post-therapeutic condition.

Biomechanical comparison of 4.0-mm short-threaded cannulated screws and 4.0-mm short-threaded cancellous screws in a canine humeral condylar fracture model.

Objective: To compare biomechanical properties of a humeral condylar fracture model stabilized either with a 4.0-mm short-threaded cancellous screw (CCS) or with a 4.0-mm short-threaded cannulated screw (CNS).

Tendon fixation in arthroscopic latissimus dorsi transfer for irreparable posterosuperior cuff tears: an in vitro biomechanical comparison of interference screw and suture anchors.

Background: The fixation of the tendon to the bone remains a challenging problem in the latissimus dorsi tendon transfer for irreparable cuff tears and can lead to unsatisfactory results. A new arthroscopic method of tendon to bone fixation using an interference screw has been developed and the purpose of this study was to compare its biomechanical properties to the ones of a standard fixation technique with anchors.

Methods: Six paired fresh frozen cadaveric human humeri were used.

Mesenchymal stem cell therapy regenerates the native bone-tendon junction after surgical repair in a degenerative rat model.

Background: The enthesis, which attaches the tendon to the bone, naturally disappears with aging, thus limiting joint mobility. Surgery is frequently needed but the clinical outcome is often poor due to the decreased natural healing capacity of the elderly. This study explored the benefits of a treatment based on injecting chondrocyte and mesenchymal stem cells (MSC) in a new rat model of degenerative enthesis repair.

In vitro biomechanical comparison of three different types of single- and double-row arthroscopic rotator cuff repairs: analysis of continuous bone-tendon contact pressure and surface during different simulated joint positions.

Hypothesis: We assessed bone-tendon contact surface and pressure with a continuous and reversible measurement system comparing 3 different double- and single-row techniques of cuff repair with simulation of different joint positions.

Materials And Methods: We reproduced a medium supraspinatus tear in 24 human cadaveric shoulders. For the 12 right shoulders, single-row suture (SRS) and then double-row bridge suture (DRBS) were used.

A novel platform for in vitro analysis of torque, forces, and three-dimensional file displacements during root canal preparations: application to ProTaper rotary files.

We proposed a new testing setup and in vitro experimental procedure allowing the analysis of the forces, torque, and file displacements during the preparation of root canals using nickel-titanium rotary endodontic files. We applied it to the preparation of 20 fresh frozen cadaveric teeth using ProTaper files (Dentsply Maillefer, Ballaigues, Switzerland), according to a clinically used sequence. During the preparations, a clinical hand motion was performed by an endodontist, and we measured the applied torque around the file axis and also the involved three-dimensional forces and 3-dimensional file displacements.

Kinematic analysis of the upper limb: a useful tool in children with cerebral palsy.

Upper limb involvement in cerebral palsy is usually more complex than lower limb involvement. Each child has a specific brain lesion and the clinical pattern is highly variable. Current clinical methods of assessment do not fully evaluate the kinematic activity during simple activities of daily life.