3D MODEL of an anatomically inert human hand: feasibility study.

OBJECTIVES: Surgery for congenital malformation of the hand is complex and protocols are not available. Simulation could help optimize results. The objective of the present study was to design, produce and assess a 3D-printed anatomical support, to improve success in rare and complex surgeries of the hand. MATERIAL AND METHODS: We acquired MRI imaging of the right hand of a 30 year-old subject, then analyzed and split the various skin layers for segmentation. Thus we created the prototype of a healthy hand, using 3D multi-material and silicone printing devices, and drew up a printing protocol suitable for all patients. We printed a base comprising bones, muscles and tendons, with a multi-material 3D printer, then used a 3D silicone printer for skin and subcutaneous fatty cell tissues in a glove-like shape. To evaluate the characteristics of the prototype, we performed a series of dissections on the synthetic hand and on a cadaveric hand in the anatomy lab, comparing realism, ease of handling and the final result of the two supports, and evaluated their respective advantages in surgical and training contexts. A grading form was given to each surgeon to establish a global score. RESULTS: This evaluation highlighted the positive and negative features of the model. The model avoided intrinsic problems of cadavers, such as muscle rigidity or tissue fragility and atrophy, and enables the anatomy of a specific patient to be rigorously respected. On the other hand, vascular and nervous networks, with their potential anatomical variants, are lacking. This preliminary phase highlighted the advantages and inconveniences of the prototype, to optimize the design and printing of future models. It is an indispensable prerequisite before performing studies in eligible pediatric patients with congenital hand malformation. CONCLUSION: The validation of 3D-printed anatomical model of a human hand opens a large field of applications in the area of preoperative surgical planning. The postoperative esthetic and functional benefit of such pre-intervention supports in complex surgery needs assessing.

[Burn: epidemiology, evaluation, organisation of care]. / Brûlures : épidémiologie, évaluation, offre de soins.

Burn: epidemiology, evaluation, organisation of care. Burn is a trauma regarding 9 000 inpatients a year in France. One third of them are infants (less than 5 years). Burn occurs seasonally and on basis of an emergency admittance. For the non-specialist, the main goal is to estimate burn area the most accurately possible (new technologies can help) and recognize signs of seriousness in order to guide the patient at best. Despite a strict and rigorous organization of burn care promoted by French healthcare regulatory authorities, more than 50% of inpatient is admitted outside burn centers (ie non specialized units).

Brûlures : épidémiologie, évaluation, offre de soins. La brûlure est un traumatisme qui concerne chaque année 9 000 hospitalisés, dont un tiers d'entre eux sont des enfants (âgés de moins de 5 ans pour la plupart), avec une saisonnalité marquée. Ces patients nécessitent une prise en charge d'urgence. Faire une évaluation rigoureuse de la surface brûlée et savoir reconnaître les signes de gravité éventuels sont indispensables à une prise en charge adaptée. Les nouvelles technologies offrent une aide précieuse à la prise en charge et permettent de joindre un professionnel de la brûlure capable de donner un avis spécialisé. En dépit d'une organisation imposée par l'État, plus de 50 % de ces patients sont encore traités en dehors des filières spécialisées.

Pulley rupture and reconstruction in rock climbers.

Hand-grip techniques in modern rock climbing generate climbing-related injuries, especially at the flexor tendon sheath level. The most frequent injury is A2 pulley rupture. The clinical diagnosis is based on bowstringing of the flexor tendon and confirmed by computed tomograph scan or magnetic resonance imaging. The surgical procedure is based on an extensor retinaculum graft to reconstruct the ruptured pulley. It is the only efficient treatment regardless of the time between accident and surgery. Thanks to this surgical procedure, patients recover or improve their former climbing performance. Some precautions before climbing may prevent this injury, and these are listed.