[Current state of doing minimal invasive total hip replacement in Germany, the use of new implants and navigation--results of a nation-wide survey]

Abstract

Aim: Total hip replacement has been developed to a very successful surgical procedure over 3 decades. In the last years many new helpful implants were introduced to the market, minimally invasive procedures were presented together with the technique of navigation. There is no scientific proof of the benefit of these procedures. The objective of this study was to collect data about the preferences of the surgeons for procedures and implants.

Methods: In a countrywide anonymous survey, staff of 240 German trauma surgery and orthopaedic surgery departments were asked about their MIS procedures and their treatment strategies (August 2006).

Results: 184 of the questionnaires have been returned representing 64,569 THRs, 65% with cementless fixation, 12.6% with bone conserving implants and 4.1% with resurfacing. We found that 77% of the respondents were doing minimally invasive THR. 34% of all THR are minimally invasive (MIS) procedures, while 23% of the patients ask for MIS. Most of the surgeons (54%) define "minimally invasive" as the preservation of muscle, tendons and soft tissue, and 33% as the length of skin incision to be less than 10 cm. 78% are convinced that long-term survival is achievable even with less invasive methods. The most common MIS approach is the anterior/anterolateral (42%), for the standard procedure (not MIS) the dorsal approach is the most used (42%), and for revision surgery the lateral approach (44%). 77% of the respondents never use navigation and 54% are convinced that there is no sense in it. 75% of MIS surgeons use special MIS instruments: 97% use redon drainage, 48% the cell-saver, 71% of the operations are performed by senior/head surgeons. The assistant quota was largest in high-volume centres.

Conclusion: Innovative implants are used with care, more than one-third of all implants are still fixed with cement. MIS is performed in one-third of the THRs and it is not driven by sensationalised reports in the media. Even the surgeons' philosophy is oriented by long-term survival, most of them are defining MIS by preventing soft tissue damage and not by the length of skin incision. The transgluteal approach is still widespread, the drawbacks are hardly detectable, the soft tissue damage irreversible. Still lacking an adequate definition of the term "MIS", it is unclear whether the soft tissue is spared or the damage to it is the same under a smaller skin incision. Computer-aided surgery in THR is not used by most of the surgeons, for the majority it is not favourable.