Costa et. al. performed recently a multi-center study including 18 trauma centers throughout the United Kingdom. They randomized patients with distal radius fractures to volar locking plates or Kirschner wires. They managed to randomize 461 patients and follow-up 90% after 1 year using self-reported scores. They could not find any difference after 1 year regarding their primary outcome, PRWE-score (−1.3 points, 95% CI -4.5 to 1.8). This was well below their stipulated minimally clinically important difference of 6 points. Could this be the end of the volar locking plate era?
The study is certainly interesting and is cause to question one of the most common orthopaedic procedures. I like the execution and how it was performed, but as always there are some things that need consideration. If the study would have shown a difference, the protocol would have been fine, but the lack of difference requires that we ask a few question:
- Some of the inclusion criteria were vague:
- “the treating surgeon believed that the patient would benefit from surgical fixation of the fracture” – If there are fractures included that do not require treatment, any difference will be attenuated. There seems to be a reasonable distribution regarding AO-class (Table 1) but it would be nice to also have shortening and an independent review of the indication with a subgroup analysis.
- “if the articular surface of the fracture could not be reduced by indirect techniques” – This is stated as an exclusion criteria, but I can’t find any indication of how many patients that were subjected to this. This could possibly cause an attenuation effect and it jeopardizes the generalizeability of the study.
- The randomization was prior to surgery, optimal would have been to randomize just before surgery. There is always a risk that the surgery considered to be more complicated will be allocated to the more experienced surgeon. There is no strong indication of surgeon selection bias in Table 2, but this is difficult to determine using the number of surgeries and seniority as proxies.
- There was little standardization of techniques. The surgical requirements were understandably set to a minimum in order to get maximum participation from the centers, unfortunately this also opens for the possibility of poor techniques at certain centers that add noise to the results, obscuring any differences.
- Lack of radiological assessment of surgery. This relates to the previous point – an attempt to assess the surgical success using plain x-rays could remedy the lack of a standardized surgical protocol.
- 1 year may be too short to show any true impact from a better anatomical positioning. The authors state an ambition to survey these patients further, but indicate that this will be mostly regarding adverse events and not for the main outcome scores.
In summary I believe that this is a valuable addition to the orthopaedic knowledge bank. It would be nice to see a revival of the Kirschner wire-technique.
M. L. Costa, J. Achten, N. R. Parsons, A. Rangan, D. Griffin, S. Tubeuf, S. E. Lamb, och on behalf of the DRAFFT Study Group, ”Percutaneous fixation with Kirschner wires versus volar locking plate fixation in adults with dorsally displaced fracture of distal radius: randomised controlled trial”, BMJ, vol 349, num aug05 2, ss g4807–g4807, aug 2014.