Simultaneous reconstruction of the Achilles tendon and soft-tissue defect using only a latissimus dorsi muscle free flap

The combined loss of the Achilles tendon and the overlying soft tissue in the young ambulant patient with expectations of a normal life is a challenging problem. These patients need not only soft tissue but also dynamic and functional reconstruction. Four cases of major defects of the Achilles tendon and overlying soft tissue after trauma are presented. In each case, the tendon and the overlying soft tissues were reconstructed using only a latissimus dorsi muscle free flap and overlying split-thickness skin graft. In conventional methods, evolved in the reconstruction of the Achilles tendon and soft tissue, the size of the defect was a limit. However, this technique can be used to reconstruct an extensive defect, including distal calf muscle to the plantar metatarsal area. In one case, the flap was harvested in a myocutaneous unit, and the skin portion was deepithelialized for the coverage and enough padding on the bony exposure area in reverse position. The purpose of the present study was to reevaluate the potential of denervated muscle flap for a force-bearing conduit as an alternative reconstructive method of the Achilles tendon. The denervated latissimus dorsi muscle in this study eventually experienced the process of atrophy and fibrosis but maintained its original length. Although there remained some atrophic muscle fibers, a fibrosis of the muscle fibers formed a tendon-like fibrous band, and so the action of the posterior calf muscle could be transmitted through the tendon-like fibrotic change of the denervated latissimus dorsi muscle. The advantages of this technique are that (1) it is a single procedure, (2) it is adaptable to a wide range of defect sizes, (3) it allows faster wound healing supported by well-vascularized tissues, (4) it produces satisfactory function of the ankle joint and a padding effect, and (5) it produces good contour of the posterior calf to the sole and an acceptable donor-site morbidity.     

Medial plantar flap based distally on the lateral plantar artery to cover a forefoot skin defect

The authors report a simple, single-step procedure to promote the distal transfer of the instep island flap for coverage of the submetatarsal weight-bearing zone. First described in 1991 by Martin et aI, this procedure remained unknown. As opposed to the medial plantar flap, this technique proposes an instep island flap based on the lateral plantar artery. The inflow and outflow of blood is assured by the anastomosis between the dorsalis pedis and lateral plantar vessels. This approach allows for the transfer of similar tissue and provides adequate coverage of the weight-bearing zone of the distal forefoot.     

Partial and complete reconstruction of Achilles tendon defects with the fasciocutaneous infragluteal free flap

Multiple attempts to repair the Achilles tendon can be associated with major soft-tissue defects of skin and tendon necessitating reconstruction with free flaps. In view of its specific anatomical characteristics, the fasciocutaneous infragluteal free flap is best suited for restoring sensibility and achieving nearly full function, including resumption of sporting activities, with minimum donor-site morbidity. The anatomy, dissection technique, and results of 100 percent successful skin and tendon defect reconstruction in seven patients are presented.     

Simultaneous reconstruction of cervical soft tissue and esophagus with a gastro-omental free flap

A microvascular transfer of gastric tube and omentum was used to simultaneously reconstruct cervical soft-tissue and esophageal defects in five patients. All patients had previous high-dose radiation and multiple flap reconstructions. The largest esophageal and soft-tissue defects were 10 cm and 160 cm2, respectively. All wounds healed primarily except for one orocutaneous fistula. There was one death from an intraoperative stroke. The gastro-omental flap is useful in cases where the reconstructive surgeon is faced with both esophageal and soft-tissue defects--particularly in heavily irradiated patients who have few reconstructive options.     

Effect of implanting a soft tissue autograft in a central-third patellar tendon defect: biomechanical and histological comparisons

Previous studies by our laboratory have demonstrated that implanting a stiffer tissue engineered construct at surgery is positively correlated with repair tissue stiffness at 12 weeks. The objective of this study was to test this correlation by implanting a construct that matches normal tissue biomechanical properties. To do this, we utilized a soft tissue patellar tendon autograft to repair a central-third patellar tendon defect. Patellar tendon autograft repairs were contrasted against an unfilled defect repaired by natural healing (NH). We hypothesized that after 12 weeks, patellar tendon autograft repairs would have biomechanical properties superior to NH. Bilateral defects were established in the central-third patellar tendon of skeletally mature (one year old), female New Zealand White rabbits (n?=?10). In one limb, the excised tissue, the patellar tendon autograft, was sutured into the defect site. In the contralateral limb, the defect was left empty (natural healing). After 12 weeks of recovery, the animals were euthanized and their limbs were dedicated to biomechanical (n?=?7) or histological (n?=?3) evaluations. Only stiffness was improved by treatment with patellar tendon autograft relative to natural healing (p?=?0.009). Additionally, neither the patellar tendon autograft nor natural healing repairs regenerated a normal zonal insertion site between the tendon and bone. Immunohistochemical staining for collagen type II demonstrated that fibrocartilage-like tissue was regenerated at the tendon-bone interface for both repairs. However, the tissue was disorganized. Insufficient tissue integration at the tendon-to-bone junction led to repair tissue failure at the insertion site during testing. It is important to re-establish the tendon-to-bone insertion site because it provides joint stability and enables force transmission from muscle to tendon and subsequent loading of the tendon. Without loading, tendon mechanical properties deteriorate. Future studies by our laboratory will investigate potential strategies to improve patellar tendon autograft integration into bone using this model.     

Tensor fasciae latae perforator flap for reconstruction of composite Achilles tendon defects with skin and vascularized fascia

The surgical management of large defects of the Achilles tendon and overlying skin is very demanding and necessitates, as a rule, a free vascularized graft. The ideal characteristics of a thin layer of skin and a strong tendon component, combined with a reliable blood supply and minimal morbidity at the donor site, have only been partially met by all previous grafts used in this situation. The authors performed reconstructions in five patients with large defects of the Achilles tendon and overlying skin by using a perforator flap derived from the tensor fasciae latae flap. A vascularized skin-subcutis-fascia lata flap could be raised by dissecting out two to three perforating arteries through the tensor fasciae latae muscle to the ascending branch of the lateral circumflex femoral artery; the muscle was left in situ in the process. All the flaps took well without complications. At final examination after an average of 20 months, the reconstructed Achilles tendon showed good functional results, although there was a 50 to 70 percent reduction in power during plantar flexion when compared with the normal side. A very good aesthetic result could be obtained after a debulking operation was performed on the skin flap.     

Implantation of a novel tissue-engineered graft in a large tendon defect initiated inflammation, accelerated fibroplasia and improved remodeling of the new Achilles tendon: a comprehensive detailed study with new insights

We constructed a new artificial collagen-based graft as a tendon proper and covered it with a polydioxanone sheath. This bioimplant was tested in vitro and also its effectiveness was tested in a large tendon defect model in vivo. A 2-cm full defect in the left Achilles tendon of all animals (n?=?120) was created. The animals were andomly divided into three groups: control (n?=?40), treated with collagen-based graft (n?=?40) and treated with collagen-Polydioxanone-based graft (n?=?40). Clinical examination was done weekly. The animals were euthanized at 60 and 120 days post-injury (DPI). The serum level of platelet-derived growth factor (PDGF) was measured. Hydroxyproline and dry matter content together with gross morphologic, histomorphometric, ultrastructural and biomechanical characteristics of the healing tissues were studied. The mechanism of host–graft interactions was studied in another 55 pilot animals. The graft was able to initiate inflammation, accelerate fibroplasia and improve remodeling of the neotenon in the defect area. Except for small remnants, most parts of the implants were gradually absorbed and substituted by a newly regenerated tendon. The preserved remnants were accepted as a part of neotenon and acted as scaffolds for the newly regenerated collagen fibrils. Unlike the controls, the treated lesions showed lower peritendinous adhesion, muscle fibrosis and atrophy and higher hydroxyproline concentration, dry matter content, ultimate strength, yield strength and modulus of elasticity. Numbers, diameter, density and differentiation of collagen fibrils were also greater in the treated lesions than the control ones. This study showed that the implant was cytocompatible, biodegradable, biocompatible and effective in tendon healing.