Why climb a ladder when you can take the elevator?

Reconstruction of the chin using an expanded deltopectoral flap following multiple recurrences of oral cancer

An important alternative to free tissue transfer in patients requiring correction of soft tissue chin defects are local and regional flaps, such as the pectoralis major myocutaneous flap and deltopectoral flap. With predictable vascular supply, potential for large size, and good aesthetic match for facial and cervical skin, the deltopectoral flap can offer the reconstructive surgeon additional options in patients who lack vessels suitable for free tissue transfer. The use of an expanded deltopectoral flap for a staged reconstruction of the chin in a patient with cancer recurrences, concomitant resections, radiation and multiple reconstructions is reported.

Combined rib-latissimus flap; the "picket fence" concept for reconstruction of upper tibia defects

Background:

Upper tibia defects ,type3b Gustilo, due to huge size and volume are very difficult to reconstruct; usually several operations are needed for bone and soft tissue defects and the definite one stage reconstruction is yet to be found.

Objectives:

In this article we reintroduce the rib- latissimus flap as an acceptable method to reconstruct tibia defects in selected cases.

Materials and Methods:

The latissimus muscle with one or two ribs revascualrized by reverse flow from perforators is harvested; the ribs are bisected after harvest yielding four to six struts of vascularized bone to fill the huge upper tibia defect. Internal fixation is very important and we favor LCP plates for long bone fixation and the rib struts are fixed in place by small titanium screws to maintain the “picket fence” design. The muscle is then wrapped around the ribs and the defect is completely reconstructed.

Results:

During the past 9 years we have used the rib-latissimus dorsi (RLD) muscle flap, without serratus muscle, in 7 patients with combined bone and soft tissue defects of the upper tibia. All the flaps healed without any major complications and only one stress fracture was seen and treated. The ribs healed and in a median of 14 months hypertrophied to the size of the upper tibia. Nonunion was not observed and patients with lower extremity defects were able to bear full weight within an average of seven months.

Conclusions:

The fractures of tibia type 3a and 3b Gustilo are devastating injuries requiring several operations. Several combinations of RLD-Serratus have already been reported but a rib-LD muscle with “picket fence” design has not been reported .The RLD transfer with two ribs divided into four struts for bone coverage and muscle to cover all the upper tibia soft tissue defect can be a useful tool in the armamentarium of the surgeon treating combined defects in a single stage.

3D microfabricated bioreactor with capillaries

We present in this paper the implementation of an innovative three dimensional (3D) microfabrication technology coupled with numerical simulation to enhance the mass transport in 3D cell culture. The core of this microfabrication technology is a high-resolution projection micro stereolithography (PmicroSL) using a spatial light modulator as a dynamic mask which enables a parallel fabrication of highly complex 3D microstructures. In this work, a set of poly (ethylene glycol) microfabricated bioreactors are demonstrated with PmicroSL technology. We observed both experimentally and numerically the regulation of metabolism and the growth of yeast cells by controlling the density of micro-capillaries. Further development of these 3D microfabricated bioreactors is expected to provide artificially constructed tissues for clinical applications.

The roles of tissue engineering and vascularisation in the development of micro-vascular networks: a review

The construction of tissue-engineered devices for medical applications is now possible in vitro using cell culture and bioreactors. Although methods of incorporating them back into the host are available, current constructs depend purely on diffusion which limits their potential. The absence of a vascular network capable of distributing oxygen and other nutrients within the tissue-engineered device is a major limiting factor in creating vascularised artificial tissues. Though bio-hybrid prostheses such as vascular bypass grafts and skin substitutes have already been developed and are being used clinically, the absence of a capillary bed linking the two systems remains the missing link. In this review, the different approaches currently being or that have been applied to vascularise tissues are identified and discussed.