A Modular Repository-based Infrastructure for Simulation Model Storage and Execution Support in the Context of In Silico Oncology and In Silico Medicine.

The plethora of available disease prediction models and the ongoing process of their application into clinical practice - following their clinical validation - have created new needs regarding their efficient handling and exploitation. Consolidation of software implementations, descriptive information, and supportive tools in a single place, offering persistent storage as well as proper management of execution results, is a priority, especially with respect to the needs of large healthcare providers. At the same time, modelers should be able to access these storage facilities under special rights, in order to upgrade and maintain their work. In addition, the end users should be provided with all the necessary interfaces for model execution and effortless result retrieval. We therefore propose a software infrastructure, based on a tool, model and data repository that handles the storage of models and pertinent execution-related data, along with functionalities for execution management, communication with third-party applications, user-friendly interfaces to access and use the infrastructure with minimal effort and basic security features.

High hip center technique using a biconical threaded Zweymüller cup in osteoarthritis secondary to congenital hip disease.

BACKGROUND: The high hip center technique used for a deficient acetabulum is reconstruction of the hip at a high center of rotation. In the literature, there is no consensus regarding the value of this technique. QUESTIONS/PURPOSES: We investigated whether the new-generation biconical threaded Zweymüller cup fixed in a high nonanatomic position in patients with arthritis secondary to congenital hip disease experienced different rates of polyethylene wear and long-term survivorship when compared with anatomically positioned cups. PATIENTS AND METHODS: We studied the polyethylene wear rate and Kaplan-Meier survivorship of 104 titanium threaded Zweymüller cups in 88 patients (81 females), placed in 70 hips at near-normal hip center and in 34 hips at a high hip center position at a distance of 31.1 to 60 mm (mean, 39.7 mm) from the interteardrop line. Minimum followup was 2 years (mean +/- SD, 8.6 +/- 3.5 years; range, 2-15 years). RESULTS: The mean linear polyethylene wear rates in the near-normal and high hip center groups were not different (0.110 +/- 0.050 mm and 0.113 +/- 0.057 mm, respectively). The Kaplan-Meier 15-year cup survivorship rates with revision for any reason as an event of interest in the near-normal and high hip center groups also were not different (97.2% [95% confidence interval, 88.5%-99.3%] and 97.1% [95% confidence interval, 73.8%-99.3%], respectively). CONCLUSIONS: The high hip center technique using a biconical threaded Zweymüller cup in patients with arthritis secondary to congenital hip disease results in a polyethylene wear rate and long-term cup survivorship comparable to those observed in anatomically positioned cups. LEVEL OF EVIDENCE: Level III, therapeutic study. See the Guidelines for Authors for a complete description of level of evidence.

High tibial osteotomies: indications and techniques.

The rationale, definition, and techniques of high tibial osteotomies are discussed. The principle indication includes unicompartmental medial or varus knee gonarthrosis with a well-maintained range of motion. Preservation of bone stock and intraarticular structures and realignment during chondral resurfacing procedures are the major advantages of high tibial osteotomies. Newer techniques have provided for less invasive surgical methods, more rigid fixation, accelerated rehabilitation, and improved accuracy of correction for high tibial osteotomies. However, permanent pain relief with high tibial osteotomies is unlikely; overall survival approximates 8 to 10 years. Subsequent conversion to a total knee arthroplasty may at times be technically demanding but the long-term results are likely to be similar to a primary total knee replacement.

Ankle arthrodesis using a tibio-calcaneal external fixator.

The results of open ankle arthrodesis in 23 patients with primary and secondary ankle-talar arthritis are presented. All patients were treated with open ankle arthrodesis using the Citieffe/CH-N external fixator with pins inserted in the tibia and the calcaneus. Union rate was 91% (21 patients) at an average of 13 weeks (range, 12-16 weeks). Mean follow-up was 6 years. Most of the patients (91%) were satisfied with the end results of the operation.