Introduction: Clinical follow-up studies are sample based, in contrast to arthroplasty register data, which refer to the entire population treated. Aim of this study is to assess the differences in revision rate to quantify bias-factors in published literature.

Materials and Methods: A structured literature review of Medline-listed peer reviewed journals on examples has been performed concerning implants with sufficient material in both data sources available. Products with inferior outcome were subsumed in a subgroup.

Results: The number of cases presented in peer reviewed journals are relatively low in general and show a high variability.

The average revision rate in peer reviewed literature is significantly lower than in arthroplasty register data-sets.

Studies published by the inventor of an implant tend to show superior outcome compared to independent publications and Arthroplasty Register data. Factors of 4 to more than 10 have been found, which has a significant impact for the results of Metaanalyses.

When an implant is taken from the market or replaced by a successor there is a significant decrease in publications, which limits the detection of failure mechanisms such as PE wear or insufficient locking mechanisms.

The final statement made about the product under investigation seem to follow a certain mainstream.

Discussion and Conclusion: Arthroplasty Register datasets are superior to Metaanalyses of peer reviewed literature concerning revision rate and the detection of failure mechanisms. Combined reviews could reduce bias factors and thereby raise the quality of reports.

The implementation of standards for deformity correction planning of axial deformities and leg length discrepancy in paediatric orthopaedics and posttraumatic cases have improved the results of postoperative alignment and joint orientation. A variety of externally and internally applicable devices have been developed for limb lengthening and deformity correction. One of the most recent developments is the Taylor Spatial Frame Fixator based on a hexapod system and a computer software for deformity correction. But little is published about clinical results using this sophisticated technique and its possible advantages over other traditional unilateral fixators or ring systems. In times of difficulties financing our health care systems, a surgeons choice for a comparatively costly system should be based on qualified data. The aim of the present study was to compare the results of deformity correction and limb lengthening using a Taylor Spatial Frame with those of other ring fixators or unilateral systems.

Between 1996 and 2004, 72 deformity corrections and/or limb lenghtenings have been performed on 52 patients with the unilateral Orthofix system (n=32), the Ilizarov system (n=22) and the TSF device (n=18). Statistical analysis showed a direct correlation between the healing index and the age at operation, as well as between the lengthening distance and the rate of complications. There were no significant differences of the healing index between all three fixators and the number of complications between the Ilizarov and TSF device, but the unilateral Orthofix fixator showed significantly more axial deviations during distraction osteogenesis.

The Taylor Spatial Frame is easier to handle than the Ilizarov fixator but did not show superior results in clinical use.