[Influence of chronic, structural changes of the muscle-tendon unit on the indication and technique of rotator cuff reconstruction]

Rotator cuff lesions are common and the incidence increases with age. After tendon rupture of the rotator cuff, the muscle-tendon unit retracts, which is accompanied by muscle fatty infiltration, atrophy, and interstitial fibrosis of the musculature, thus, fundamentally changing the muscle architecture. These changes are important prognostic factors for the operative rotator cuff reconstruction outcome. Selection of the correct time point for reconstruction as well as the optimal mechanical fixation technique are decisive for successful attachment at the tendon-to-bone insertion site. Thus, knowledge of the pathophysiological processes plays an important role. The goal of this article is to establish a relationship between currently existing evidence with respect to the preoperatively existing changes of the muscle-tendon unit and the choice of the time for the operation and the operative technique.

Development and implementation of a web-enabled 3D consultation tool for breast augmentation surgery based on 3D-image reconstruction of 2D pictures

Producing a rich, personalized Web-based consultation tool for plastic surgeons and patients is challenging.

Reconstruction of large supra-eyebrow and forehead defects using the hatchet flap principle and sparing sensory nerve branches

To reconstruct a forehead defect, a plastic surgeon must be knowledgeable about the neural, vascular, and muscular anatomy. The position of fixed structures such as eyebrows and hairline should be respected. For the past 5 years, we have used double hatchet flaps for reconstruction of relatively large supra-eyebrow and forehead defects. Because this flap does not appear to be among the techniques used by young plastic surgeons, we thought that it would be valuable to report our experience.

Evaluation of late results in breast reconstruction by latissimus dorsi flap and prosthesis implantation

BACKGROUND: Breast reconstruction by latissimus dorsi myocutaneous flap in combination with a prosthesis is a widely used, well-established procedure. Short- and medium-term evaluation after this procedure is well described in the literature, but there have been no evaluations of the late course (over 10 years) published until now. METHODS: In a retrospective study, 68 patients operated on by means of this technique at the authors' institution from 1981 to 1993 resulting in a minimal follow-up of 10 years were included. Patients were invited to an interrogation, clinical examination, and photographic documentation (n = 51). Incidence of late flap or prosthesis-related complications, number of and indications for corrective procedures, and the correlation of the patients' subjective judgment and objective results in the late course have been the main interest of the authors' survey. RESULTS: The authors found that 50 percent of the patients needed a late reoperation for change or removal of the prosthesis. Seven (10 percent) of 68 patients needed a definitive removal of the implant in the late course. Assessment of the photographic documentation of the late result by four nonprofessionals showed that the objective aesthetic results of a considerable number of the authors' reconstructions were not sufficient. CONCLUSION: The procedure combines two basic techniques of reconstructive surgery, the soft-tissue restoration by a pedicled flap as the autologous reconstructive component and the volume reconstruction by prosthesis. Therefore, these patients are subject to a cumulation of the basic morbidity of the two techniques. The authors conclude that the indication for this procedure should be restricted to patients not qualifying for "pure" reconstructive techniques.

Reconstruction of patient-specific 3D bone surface from 2D calibrated fluoroscopic images and point distribution model

Reconstruction of patient-specific 3D bone surface from 2D calibrated fluoroscopic images and a point distribution model is discussed. We present a 2D/3D reconstruction scheme combining statistical extrapolation and regularized shape deformation with an iterative image-to-model correspondence establishing algorithm, and show its application to reconstruct the surface of proximal femur. The image-to-model correspondence is established using a non-rigid 2D point matching process, which iteratively uses a symmetric injective nearest-neighbor mapping operator and 2D thin-plate splines based deformation to find a fraction of best matched 2D point pairs between features detected from the fluoroscopic images and those extracted from the 3D model. The obtained 2D point pairs are then used to set up a set of 3D point pairs such that we turn a 2D/3D reconstruction problem to a 3D/3D one. We designed and conducted experiments on 11 cadaveric femurs to validate the present reconstruction scheme. An average mean reconstruction error of 1.2 mm was found when two fluoroscopic images were used for each bone. It decreased to 1.0 mm when three fluoroscopic images were used.