Clinical studies

One of the key objectives of AOCID is to organize and conduct clinical studies that provide evidence regarding the clinical benefit of AO methods and implants. The gold standard study design to achieve this is a randomized clinical trial (RCT). We therefore considered this design for the LCP distal radius study right from the start.

While simple on paper, the process of randomization met with some practical obstacles. Which treatment would be optimal to compare the LCP with? For which indication? Would surgeons be prepared to randomize patients? In fact, we could not find a consensus on the best control treatment, since the new LCP plate is based on a new concept and does not replace an existing system on a one by one basis. An RCT was judged inappropriate, in particular because surgeons were convinced that the LCP will provide a better outcome for the patient and therefore were not willing to use the conventional system any longer.

The best compromise was to conduct an observational study where the treatment decision remains in the hand of the surgeons. This design allows documentation of the range of indications for treatment with the LCP, and both clinical and radiological outcomes, after plating of the distal radius. By collecting data from a large number of cases, we will identify different cohorts (e.g. patients treated with different plates) that will be compared.

The LCP Distal radius study includes three prospective studies and one retrospective study.

• Conservative distal radius study in the UK documenting all distal radius fractures, and all types of treatment (majority of fractures treated conservatively).
• LCP 3.5 mm distal radius study, involving centers mainly using the 3.5 mm LCP system (10 centers).
• LCP 2.4 mm distal radius study, focused on the 2.4mm LCP system (6 centers).
• Retrospective study documenting the treatment of all distal radius fractures in the past year (before the LCP plate was available). The same clinical journal form is used, with no follow-up visits, and no collection of X-ray images (7 centers).

We have two types of questionnaires for the prospective studies, one for all plated cases (any type of plate and fulfilling inclusion and exclusion criteria), including follow-up forms up to two years post-operatively, and a shorter one for all other cases (making the clinical journal).

A schematic overview of the LCP 3.5 mm and 2.4mm study, combined with the retrospective study is shown in the figure below. The same inclusion and exclusion criteria, as well as clinical (including the Gartland and Werley, the DASH and the SF-36 scoring systems) and radiological (centrally evaluated) outcome criteria are used in the different prospective studies. While follow-up is implemented for all cases in the "Conservative" distal radius study, only plated cases are followed in the two other prospective studies.

Special attention will be given to the expected advantages of the new LCP concept as well as to maintenance of reduction, the additional use of bone grafting, and the learning curve. The studies are controlled in order allow a comparison of the LCP systems to other conventional plating systems and conservative treatment of distal radius fractures. The retrospective part of the study (documenting the situation before the introduction of the LCP system) will show whether any shift in indication from e.g. external fixator to the LCP system has occurred and in order to define a control group accordingly for future studies.

The different studies were started at the end of 2001.