Minimally invasive: not the bee’s knees

20. October 2011

In Germany too much surgery is done, it is said again and again. "Innovations" are said to be popular. But regardless of whether that's true, something is indisputably certain: New is not always better. Just one example of this is the minimally invasive implantation of knee prostheses.

The second-opinion German portal “Vorsicht Operation“ (caution operation) and the statements of its founder opened some debates recently. “I can’t stand how operations go on out there which bring nothing to the patient, but benefit only the doctor”, Heidelberg professor and knee expert Hans Pässler is quoted, who along with other leading orthopaedists and surgeons brought the portal to life.

A continuous controversy

Among the operations that have increased in Germany are hip implantations and knee prostheses. Pensioners without an artificial knee or hip could soon be in the minority, it was said in a 2010 press release from German health insurer Barmer GEK. “With respect to the insertion of endoprostheses we are world champions, in this even the U.S. is far behind us,” cites Professor Volker Ewerbeck of the University Hospital Heidelberg, who recently reiterated indications of some supply problems. There are no medical reasons, he says. The former president of the Orthopaedic Society, Professor Joachim Grifka of the University Hospital Regensburg, even speaks of a “concerning over-supply.”

The facts are well known: Germany is the leader in Europe in numbers of artificial hip and knee joints. Nearly 400,000 of these procedures the German Society for Orthopaedics and Orthopaedic Surgery has counted – and the tendency is a rising one. If one makes a statistical correction for the population’s age increase, the provision of hip joints since 2003 has increased by nine percent, with knee joints by 43 percent, according to Barmer GEK. The “number of knee endoprosthesis implantations is growing annually by about 6.8 percent” alone, Mannheim-based orthopedic surgeons Professor Hanns-Peter Scharf and Dr. Astrid Schulze also add in one contributory article in 2010 in Endoprothetic Knee Replacement.

var dcmv = new DcMediaViewer(); dcmv.embed({“slider”: “0evVEF3YeqWVWkzojx3FeQ”, “view”: “max”, “tooltips”: false });

The figures can’t be accounted for solely by demographic trends says Barmer GEK, one of those who pay the most for this development. The question is allowed to be raised here about “whether the range of indications for surgery is too wide so that there is already a tendency to overprovision,” says Dr. Rolf-Ulrich Schlenker, deputy chairman of the fund. However “perhaps we previously had a deficiency, and are only now slowly approaching reasonable levels of provision. I believe that in the past we did not adequately provide for many patients”, says Professor Karsten Dreinhöfer of Medical Park Berlin Humboldtmühle, vice president of the Professional Association of Specialists in Orthopedics and Trauma Surgery. He also believes that there still “are a lot of patients who would benefit from a prosthesis, but unfortunately have not been operated on”. Resolving the question of whether there is in the area of prosthetics an overprovision, underprovision or misuse will probably also hardly be assisted by the Arthroplasty Register which was set up this year. Participation is voluntary. Such a register just doesn’t say anything about the specific indications, says Dreinhöfer.
In relation to the question about what the real situation is with respect to provision, the remark of Hamburg biomechanics professor Michael Morlock probably still holds: At a function of the German Federation of Medical Technology in Berlin he stated:
Everyone can say what he wants, as there is no reliable solid data.

Study analysis shows: mininmal-invasive implantation is no advancement

Nevertheless, it is undisputed that, on the one hand, new medical methods are usually something sought-after; they are ennobled by terms such as innovation or “breakthrough” and therefore ever increasingly lead to a “supply-induced volume expansion,” as stated in the “double-Dutch” of the experts. On the other hand, it is undeniable that new is not always really better than old. It is often also more a matter of perspective: What is a step forward for scientists and is for companies a “breakthrough” is for health insurance another cost factor and for patients sometimes just a hope. An example of the problem “new versus old” ist the choice between “minimally invasive or conventional implantation of knee endoprostheses”.

Since minimally-invasive is a general trend, for several years there have also been knee prostheses happily implanted by minimally invasive methods. Orthopedists in Ulm working under Professor Heiko Reichel have therefore looked more precisely, to see what advantages and disadvantages this method has. For their meta-analysis (author Dr. Thomas Kappe), the team evaluated 28 prospective and retrospective studies. 

Altogether 2783 total knee prostheses were studied. Studies that compare minimally invasive to conventional-entry were analysed for the parameters of blood loss, soft tissue trauma, post-operative pain and mobilisation, mobility, implant positioning, complications and clinical outcomes. The sobering conclusion of the Ulm group: The minimally invasive surgical technique have in none of the actual problem areas brought any progress. Minimally invasive approaches have indeed allowed the implantation of a knee prosthesis via a shorter incision. But that’s just cosmetic. In contrast to a “potentially more rapid remobilisation” are nevertheless the “risks of impaired wound healing, increased complications and often incorrectly positioned implants.” Even in regard to perioperative blood loss there is no advantage “derivable“ from the available data. However, there are advantages in postoperative pain, analgesic requirements are therefore lower.

In addition, the patients were mobile again sooner, rehabilitation could be started earlier – a plus, to which recently Dr. Andreas Haider, chief physician of the Sana Clinics Sommerfeld, also pointed at the annual meeting of the North German Orthopaedic and trauma surgeons. Nevertheless, the results are not “overwhelming”. Perhaps they may even provide an overly positive picture because In the meta-analysis of the Ulm studies there were exclusively published results used from specialised centres with experienced surgeons. Complication rates for minimally-invasive knee prostheses carried out in less specialised centres could differ significantly from those of conventional implantation, “especially during the learning curve period”, Thomas Kappe and his colleagues emphasise.

2 rating(s) (2.5 ø)

Copyright © 2020 DocCheck Medical Services GmbH
Follow DocCheck: