Pedicled-perforator (propeller) flaps in lower extremity defects: a systematic review

Pedicled-perforator (propeller) flaps for lower extremity reconstruction have gained popularity due to minimal donor site morbidity, relatively simple surgical technique, and replacement of tissue using "like-by-like" principles. We reviewed and analyzed the clinical use of these flaps in regards to patient age and gender, etiology and location of the defect, size and type of flap, arc of rotation, and complications to determine the reliability of this technique. A systematic review of the PubMed database using search terms to include perforator, pedicled, and propeller flaps in the lower extremity. Data from 15 case series provided 186 cases of pedicled-perforator (propeller) flaps for analysis using Chi-square tests. The Peroneal Artery Perforator (PAP) flaps and Posterior Tibial Artery Perforator (PTAP) flaps were the most frequently used flaps. The overall complication rate was 25.8% and the failure rate was 1.1%. No significant differences were found in complication rate related to age, gender, etiology or location of the defect, type or size of the flap. The most common complications were partial flap loss and venous congestion (11.3 and 8.1%). Pedicled-perforator flaps appear to be a reliable and safe procedure for the coverage soft tissue defects of the lower extremity based on favorable results reported in the literature.     

Mesodiencephalic projections to the vestibular complex in the cat

The distribution of cells in the rostral medial mesencephalon and caudal diencephalon which project to the vestibular complex was mapped in the cat by using retrograde axonal transport of wheat germ agglutinin conjugated to horseradish peroxidase (WGA-HRP). Subsequent experiments using anterograde transport of WGA-HRP clarified the position of the terminations of the mesodiencephalic-derived afferents in the vestibular complex. After large injections which involved the entire vestibular complex, retrogradely labeled cells were seen in both the ipsilateral and contralateral interstitial nucleus of Cajal (INC) and were more numerous in its rostral pole. Labeled cells also occurred in the perifascicular region, both immediately adjacent to the fasciculus retroflexus and rostroventral to it. Fusiform midline cells of the Edinger-Westphal nucleus were also labeled, as well as a number of cells in the adjacent somatic portion of the oculomotor complex (OMC). Another group of labeled cells was observed within the contralateral medial terminal nucleus of the accessory optic tract (MTN) and in the posterior hypothalamic nucleus. Injections limited to subregions of the vestibular complex resulted in similar but slightly varying distributions and numbers of retrogradely labeled cells. After injections covering the caudal half of the medial vestibular nucleus (MVN) and descending vestibular nucleus (DVN), labeled cells in the INC and tegmentum dorsal to it were especially prominent, but none was seen in the MTN or OMC. Injections placed in the rostral MVN, lateral vestibular nucleus, y group, and superior vestibular nucleus resulted in a distribution of labeled cells similar to that seen following global vestibular injections, but these cells were fewer in number. After an injection confined to the y group, a small number of retrogradely labeled cells were seen in the rostral pole of the INC and immediately ventral to the fasciculus retroflexus. Projections from the rostral medial mesencephalon and caudal diencephalon to the MVN, DVN, and y group were confirmed by using anterograde transport of WGA-HRP. Direct projections from the INC-perifascicular regions and somatic neurons of the OMC to the caudal vestibular complex could play a role in eye-head coordination. Those projections from the rostral INC and MTN to the rostral vestibular complex may play a role in vertical eye movements and responses to visual stimuli which move in the vertical plane.     

Comparative topography of projections from the mesodiencephalic junction to the inferior olive, vestibular nuclei, and upper cervical cord in the cat

Distributions of neurons located in the central rostral mesencephalon and caudal diencephalon that project to the upper cervical spinal cord, vestibular nuclei, or inferior olive were studied in the cat by using retrograde axonal transport of wheat germ agglutinin conjugated to horseradish peroxidase (WGA-HRP). Afferent sources to all of these targets were observed in the interstitial nucleus of Cajal (INC), the region surrounding the fasciculus retroflexus (PF), and the nucleus of the fields of Forel (NFF). Three-dimensional reconstruction revealed differences in densities of cells projecting from these common areas. Spinal projecting cells were present in slightly greater numbers in the caudal two-thirds of the INC, whereas those projecting to the vestibular complex were more numerous in the rostral two-thirds of this nucleus. A relatively smaller number of olivary projecting cells were dispersed throughout the INC. Olivary afferent sources outnumber those with spinally directed or vestibularly directed axons in the PF region. In the fields of Forel, cells projecting to the vestibular nuclei or inferior olive were concentrated medially, whereas cells projecting to the spinal cord appeared both medially and laterally. Each type of afferent source was also seen in the nucleus of the posterior commissure and the posterior ventral lateral hypothalamic area. Unique sources of afferents to the inferior olive were observed in the parvicellular red nucleus (ipsilateral to the injections) and the anterior and posterior pretectal nuclei. A large number of labeled neurons was seen in the nucleus of Darkschewitsch after injections of tracer into the inferior olive, but this projection did not appear to be unique, as small numbers of labeled cells were also seen after injections into the cervical spinal cord. The Edinger-Westphal nucleus and the adjacent somatic oculomotor nucleus contained cells which projected separately to the spinal cord or the vestibular complex, and the superior colliculus contained cells which projected separately to the contralateral spinal cord or the contralateral inferior olive. In this study, it was also noted that neurons in the medial terminal nucleus of the accessory optic tract projected to the ipsilateral inferior olive or to the contralateral vestibular complex. These differences in locations and densities of cells projecting to the cervical spinal cord, vestibular complex, and inferior olive may underlie functional specializations in these areas in relation to vertical eye and head movement control and to neural systems controlling postural adjustments accompanying limb movements.     

Projection from the vestibular nuclei to the inferior olive in the cat: An autoradiographic and horseradish peroxidase study

Injections of horseradish peroxidase (HRP) in the inferior olive of 13 cats resulted in the labeling of neurons in the medial (MVN) and descending vestibular nuclei (DVN) as well as in subgroups g, p.h., s.v., x and z. The contribution of groups p.h. and z. could not be definitively established. Injections of triated leucine in the vestibular nuclei and adjacent reticular formation in 4 cats indicated that the previously identified vestibular nuclei and subgroups project bilaterally to the dorsomedial cell column and ipsilaterally to subnucleus beta of the inferior olive. In view of the known topography of olivocerebellar projections, the present results suggest that climbing fiber-mediated vestibular information may influence the uvula and the fastigial nucleus.     

Maximizing aesthetic outcome in autologous breast reconstruction with implants and lipofilling

Background

Free flap breast reconstruction is an option widely sought in postmastectomy breast reconstruction. However, the volume of autologous tissue from the patient is often not sufficient for symmetrical reconstruction. In these cases, flaps can be used in combination with implants or autologous fat injections to augment volume and achieve shape, symmetry, and contour.

Methods

A retrospective chart review was performed on patients who underwent postmastectomy free flap reconstruction with secondary augmentation using autologous fat grafting or implant from 2008 to 2011.

Results

Twenty-four patients (39 breasts) received further augmentation of autologous tissue reconstruction during this period. Sixteen patients (26 breasts) had fat graft augmentation only, four patients (eight breasts) had implant augmentation only, and three patients (five breasts) had both procedures. Among patients who had fat grafting, operative intervention was required twice for fat necrosis. Contrastingly, of patients who received implants, one patient required operative intervention for implant malpositioning. These differences were not significant (P?=?0.57). The group with both fat grafting and implant augmentation had significantly higher aesthetic scores regarding overall appearance, contour, and volume, but not projection, than the group with fat grafting only and the group with implant only.

Conclusions

Autologous fat grafting offers several contouring aesthetic advantages, including selectively augmenting areas of hollowness to improve contour and maximize symmetry. However, implant augmentation generally allows for a larger increase in projection in a single procedure, with similar rates of postaugmentation complications. Use of both autologous fat grafting and implant augmentation may allow for superior aesthetic results. Level of Evidence: Level IV, therapeutic study.