Einsatz eines modularen Knierevisionssystems MML im Rahmen des Knieprothesenwechsels und der Tumorendoprothetik

Abstract

Increasing age and a higher level of mobility lead to an increasing incidence in revision arthroplasty after total knee replacement and tumor surgery. So far, the reconstruction of large defects in bony and soft tissue environments can be accomplished by the modern modular components of revision implants. The consecutive reconstruction of the extensor mechanism in extended revision has its own drawbacks and is often associated with significant functional limitations for the patient. Specially designed implants and methods are required to generate good functional results. The modular knee revision system MML provides specific modifications of the tibial component for reconstruction of the extensor mechanism. Combined with artificial strips, an excellent functional outcome could be achieved. In this study, 70 patients were operated with the MML endoprosthesis in knee revision or tumor surgery. An excellent functional outcome could be determined. At 7 years after surgery, an average of 32+/-13 points was achieved on the Oxford Knee Score. The outcome measurement using the functional scoring system of the American Knee Society (AKS score) showed similarly good results with 71+/-25 points out of 100. A minor deficit of only 2 degrees in active extension could be observed after reconstruction of the extensor mechanism. In conclusion, we have demonstrated that the MML modular revision system is appropriate for reconstruction of segmental bone defects.

Distal femoral replacement with the MML system: a single center experience with an average follow-up of 86 months

“…Hence, the design was changed and the second-generation prostheses had strengthened central axis bolts [16]. In our cohort, only second generation prostheses were implanted.…”

“…Hence, it is not well understood whether complications after DFR depend on the indication for surgery or, for instance, the patients’ age. Further, there have been but few reports that evaluated functional outcomes after these reconstructions with the modular Munich-Luebeck (MML) knee prosthesis for various indications [15, 16]. …”

Short- to long-term follow-up of total femoral replacement in non-oncologic patients

“…In the literature, the incidence of prosthetic component breakage in megaprostheses ranges between 0% and 7.7%, with lower incidences in TFR compared to distal or proximal femoral replacement. Again, this might be accounted for by an absence of diaphyseal stems in TFR which are a known weak spot in modular megaprostheses [24]. Other authors conclude, reduced mobility and activity in this population as a reason for lower rates of structural failure probably due to lesser activity in this population [16, 18, 19, 21–23].…”

Is total femoral replacement for non-oncologic and oncologic indications a safe procedure in limb preservation surgery? A single center experience of 22 cases

“…In the literature, the incidence of prosthetic component breakage in megaprostheses is 0–7.7%, with lower incidences in TFR than in PFR/DFR. Again, this might be attributed to the absence of diaphyseal stems in TFR, which are known weak spots in modular megaprostheses [ 30 ]. Other authors conclude that the lower mobility and activity in this population is a reason for lower rates of structural failure [ 10 , 23 , 25 , 26 , 28 , 29 ].…”