Designing and Prototyping of New Device for Scapholunate Ligament Repair

Abstract

Scapholunate instability, caused mainly due to tears in the scapholunate interosseous ligament (SLIL), may result in chronic pain, hand weakness, and lack of motion. Several open surgery procedures are used to repair it however long recovery time, widespread scarring and movement limitations are associated. Focusing on arthroscopy surgery, the combination of arthroscopy techniques and a prosthesis could be a good solution to manage it. A new prosthesis to substitute the SLIL was designed and manufactured. The design process was assessed by expert surgeons in wrist arthroscopy and the prototype manufactured allowed to analyze advantages and drawbacks of the adopted solution.

Headless Screw Fixation of Metacarpal Neck Fractures: A Mechanical Comparative Analysis

“…HCSs have been used with increasing frequency in hand surgery. This construct was initially described for scaphoid fracture fixation, 1,11 but its use has recently increased to a number of different injuries including scapholunate ligament tears, 25 radial and ulnar styloid fractures, 20 and fractures of the phalanges and metacarpals. 7 Metacarpal neck and shaft fracture fixation with an HCS was recently studied in vivo with promising functional outcomes and high union rates at 3-month follow-up.…”

Equivalent Representation Form of Oscillators with Elastic and Damping Nonlinear Terms

“…In (11) and (12), and are fitting parameters whose values must be fixed to ensure that the equivalent restoring forces are qualitatively and quantitatively similar to those of the original equations of motion. During the transformation process, the values of 0 and are assumed to remain constant.…”

“…This dynamics model is known as the one-fifth power law model [9]. Of course, there are other models that consider different values of to characterize the damping and the elastic nonlinearities observed in different experimental measurements [10][11][12]. In an attempt to cover the gap between viscous, dry friction, and drag forces in turbulent fluids, Litak and coworkers considered a nonlinear damping term with a fractional exponent to model the behavior of double well oscillators.…”

Design optimization using Statistical Confidence Boundaries of response surfaces: Application to robust design of a biomedical implant

“…In the common life, wounds can appear, due to sports activities or accidents in the home. Often, prostheses or implants are then used to restore the functional capacity of the patient [1]. The design of biomedical products is however constrained by many criteria (biocompatibility of the materials, lifespan of the implant, small available geometrical space...) and needs multi-objective optimization methods.…”