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This chapter presents an effective means for exploring aggressive motorcycle trajectories. It discusses the problem of generating an optimal speed profile, taking into account the constraints imposed to the maximum acceleration and deceleration. The chapter describes a nonlinear control system (the virtual rider) with the capability of driving a multibody two-wheeled vehicle along a general user-specified ground path with a desired velocity profile. It describes a reduced-order manoeuvre regulation controller for controlling a multibody motorcycle model along the obtained optimal speed profile. The virtual rider is based on the sliding plane motorcycle (SPM) model. Dynamics inversion for the SPM model is obtained by embedding its dynamics into an extended control system by adding two non-physical control inputs. By optimizing away this additional control effort, a flatland trajectory can be converted into a full state-input trajectory. The controller is connected directly to an interface, allowing for closed-loop simulations.

Background The nose is a functionally complex organ with also a critical role in aesthetics. For reconstruction of full thickness nasal defects, multiple stages are needed and there is risk for resorption resulting in residual deformity. The aim of this report was to develop and evaluate a new method for full thickness total/subtotal nose reconstruction using the medial femoral condyle free flap (MFCFF) in combination with a paramedian forehead flap. Methods Between November 2015 and January 2018, eight patients (four males, four females) mean age 52 years (range 40-73 years) undergoing a total/subtotal nasal excision and subsequential reconstruction with MFCFF plus paramedian forehead flap were enrolled. Six cases were squamous cell carcinomas while two were basal cell carcinomas. The MFCFF was stabilized, with the periosteum as inner layer, with plates and a paramedian forehead flap was used as external skin coverage. All patients were evaluated for with postoperative nasal endoscopy and CT scan. A postoperative questionnaire was given 6 months after surgery. Results The mean MFCFF size was 2-3.8 cm × 2.25-2.5 cm with a mean pedicle length of 6.3 cm (range 4.1-9.4 cm). The postoperative period was uneventful. The mean follow-up was 16 months, no bone displacement or resorption was observed at the CT scan, no evidence of nasal stenosis occurred. All patients had a satisfying aesthetic evaluation and a good subjective nasal function. Conclusions In this series, the MFCFF in combination with the paramedian forehead flap appeared to provide a valid subtotal nose reconstruction, allowing for the recreation of all the three nasal layers and maintaining the nose projection and airway patency in the long term.

Soft tissue defects of the lower extremity that expose underlying bones, joints, and tendons pose challenging problems and generally require free tissue transfer for a successful reconstruction. Historically, muscle flaps were the gold standard choice for lower limb reconstruction. To obviate the unpredictable appearance and high donor-site morbidity of muscle flaps, fasciocutaneous flaps were introduced. Recently, perforator flaps, such as the anterolateral thigh flap, gained a leading role in the reconstructive scenario. There is growing evidence in the literature supporting that fasciocutaneous and perforator flaps are comparable to muscle flaps in terms of flap survival, postoperative infection, osteomyelitis, bone union, and ambulation. With the advances of knowledge in perforator anatomy and their mapping, a new era of lower limb reconstruction has begun. Propeller flap could be raised on any suitable perforator vessel and, without the aid of microsurgical anastomosis, used to restore small- to middle-sized soft tissue defects. In this review, we intend to analyze pros and cons of muscle and fasciocutaneous free flaps and the applicability of the propeller flaps in lower limb reconstruction.

Background: The goal of this study was to evaluate with a three-dimensional method the long-term quality of alveolar ossification in unilateral cleft lip and palate patients who underwent early secondary gingivoalveoloplasty according to the Milan surgical protocol. Methods: The sample consisted of 63 computed tomographic scans of unilateral cleft lip and palate patients in permanent dentition. The average age at the time of assessment was 15.7 years. Alveolar thickness, nasoalveolar height, nasal floor ossification, and hard palate morphology were evaluated using dental, axial, and coronal cuts on computed tomographic scans and three-dimensional models. All measurements were normalized and ratios of the affected side versus the nonaffected side were provided. Volume measurements and ratios of each hemimaxilla were added. The presence or absence of the permanent lateral incisor on the cleft side was also recorded. Results: Alveolar thickness and height were ideal or good, respectively, in 89.5 and 91.4 percent of the sample. Insufficient ossification (