Scalp Surgery: Anatomic and Biomechanical Considerations

BACKGROUND: The purpose of surgery is to effect functional and/or cosmetic benefit while causing as few adverse consequences as possible. At its core lies incision/excision, tissue mobilization, and reconstruction. Each body region presents its own particular surgical challenge. Scalp is made up of collagen, elastin, blood vessels, nerve fibers, and lymphatics with mucopolysaccharide ground substance and tissue fluid, together with hair follicles, sweat, and sebaceous glands. All these elements are anatomically and biologically affected by each modality of surgery. OBJECTIVE: To establish technical guidelines for scalp surgery compatible with maximal functional/cosmetic benefit and complication-free results. METHODS: More than 3000 scalp operations done personally were reviewed. These included the entire spectrum of plastic and reconstructive surgery and hair restoration procedures. RESULTS: Some guidelines compatible with improved scalp surgery results were derived. CONCLUSION: Complication-free scalp surgery is most likely to occur when incisions spare neurovascular structures; do not transect collagen or elastin; undermining is modest and discriminate; deep plane fixation is used; and hair directional orientation (drape) is preserved.     

Initial Multi-institutional Experience with Transoral Robotic Surgery

Objective To assess the initial experience for transoral robotic surgery (TORS), as observed in the French TORS group. Study Design A multi-institutional prospective cohort study. Setting Seven tertiary referral centers. Subjects and Methods One hundred thirty consecutive patients who were scheduled for a TORS between October 2008 and March 2011 were included. The operative times, conversion rates, morbidity, and alternatives were described. The serious adverse effects encountered were analyzed, and recommendations for avoiding them are specified. Results Most of the patients (65%) had a laryngeal (supraglottic) and/or hypopharyngeal resection. Thirty-nine of the 130 patients receiving TORS would have had a transoral laser resection as their alternative surgery. The tumor exposure was suboptimal in 26% of the cases. Six of the 130 patients needed conversion to an open approach. There were 15 postoperative hemorrhages and 2 deaths due to posthemorrhage complications in patients with significant comorbidities at 9 and 18 days after the surgery. The median setup and procedure times were 52 ± 46 and 90 ± 92 minutes, respectively. The learning curve was characterized by better selection and management of potential patients. Conclusion The visualization offered by the robotic assistance allowed transoral resections of tumors that were difficult to resect or unresectable by laser surgery. Self-assessment of surgical exposure and a decrease in the need to convert to an open procedure over time suggested improvement in TORS-related surgical skills. Nevertheless, strict patient selection is essential. Even with a minimally invasive approach, some patients will need a tracheostomy for safety reasons.     

Anteriorly Based Pericranial Flap: An Anatomic Study of Feeding Arteries

The purpose of this study was to obtain anatomic data on the branching levels of the deep branches of the supraorbital artery (SoA) and of the supratrochlear artery (StA) in pericranial flaps. Ten preserved cadavers were used for this study. Each vessel was identified on 12 sides. The deep branch of the SoA had a larger caliber than that of the StA in seven of nine sides. The branching level of the deep branch of the SoA was cephalad to that of the StA on six of nine sides. The deep branch of the SoA diverged shortly after emerging from the supraorbital foramen or notch. However, there were a few cases in which the branch originated at a distance of a few millimeters before or after the foramen or notch. From a practical standpoint, dissection of this pericranial flap below the level of the supraorbital ridge is not advised, and preservation of both feeding arteries is encouraged in order to establish abundant vascularity for this flap.     

Retrosigmoid Transmeatal Approach: An Anatomic Study of an Approach Used for Preservation of Hearing in Acoustic Neuroma Surgery and Vestibular Neurotomy

The limitations of the transmeatal phase of the retrosigmoid transmeatal approach are shown, and the problems of opening the internal acoustic meatus via this approach and the criteria for its use are discussed.     

Surgical Planning for Flexor Digitorum Longus Tendon Transfers: An Anatomic Study

Posterior tibial tendon dysfunction is often coupled with various degrees of hindfoot valgus and equinus. Preoperative planning is essential to appropriate procedure choice and surgical efficiency. The purpose of the present study was to assess the anatomy at the harvest site for flexor digitorum longus tendon transfer, specifically at the master knot of Henry. Thirty fresh-frozen below-the-knee cadavers were used for dissection. A standard anatomic approach was performed for posterior tibial tendon debridement and flexor digitorum longus tendon transfer. The flexor digitorum longus tendon was harvested and measured at the master knot of Henry. The present anatomic study evaluated the tendon width of the flexor digitorum longus tendon at a common harvest site. Of the 30 specimens, 20 (67%) measured 5 mm and 10 (33%) measured 4 mm. A 5.0-mm interference screw would be acceptable in each specimen and therefore would be the safest choice. A 4.0-mm interference screw would be acceptable in only 33% of the specimens. Males have a slightly more robust flexor digitorum longus tendon than females at the harvest site. This information will assist surgeons in preoperative planning during stage II flatfoot correction for posterior tibial tendon dysfunction.     

An Anatomic Safe Zone for Posterior Ankle Arthroscopy: A Cadaver Study

Posterior ankle arthroscopy has traditionally been associated with concern for injury to the posterior tibial nerve and vessels, and this concern is greatest when the patient is positioned supine. Positioning the patient prone could be a safer method for posterior ankle arthroscopy. The purpose of this cadaver study was to determine the anatomic safe zone devoid of vital structures relative to the posteromedial and posterolateral arthroscopic portals created. In addition, exposure of the posterior ankle was evaluated by direct visualization and fluoroscopy to determine the relative utility of these portals. Based on our findings, which are consistent with other previously reported results, we believe that a wide range of ankle pathology can be suited to treatment by means of posterior arthroscopy with the patient in the prone position.     

The Precochlear Approach to the Anterior Petrous Apex: An Anatomic Study

The petrous apex is the most inaccessible portion of the temporal bone and surgical exposure presents considerable challenge. The transmastoid precochlear approach offers a direct intra temporal route to this region, providing good visual exposure with cochlea preservation. An anatomic study of 20 human temporal bones was performed to delineate the landmarks for this approach. Measurements to the tegmen tympani, carotid artery, and the anterior-superior limit of the cochlea were made from the cochleariform process, a constant landmark in the middle ear. Distances to the tegmen averaged 5.4 mm (range: 3.5-9 mm), to the carotid artery 9.3 mm (8-11 mm), and the cochlea 3.1 mm (2-5 mm). The entry to the apex admitted an average burr size of 3.5 mm (2-7 mm). We anticipate this approach will prove useful in the treatment of benign petrous apex lesions.