[slideshow_deploy id=’286′]
Bidirectional Total Hip Prosthesis – “Have It Both Ways”
After total hip arthroplasty, dislocation is one of the most frequent serious early complications. This occurs in part due to impingement (catching and leverage of the neck-cup on the inlay/cup border). Impingement may also negatively impact long-term outcomes. Through isolation of the two main trajectories of motion, and modifications with corresponding gaps to the inlay/cup areas as well as oppositional banking in the abduction/adduction plane, the combination of a snap-fit acetabular cup with reduced cup profile was the result: the „bidirectional total hip prosthesis“, invented and engineered by Dr. Dr. Andrej Nowakowski at the Osteoarthritis Research Center. Under standardized parameters, the ranges of impingement for typical implants are not directly opposite one another (at 180°), but are found instead at an angle of 108.3°. Complications such as dislocation and impingement may possibly be avoided with the bidirectional total hip prosthesis. Typical implantation parameters yield an implant design with rotational asymmetr
Transversal Support Tibial Plateau – “For Retaining Both Cruciate Ligaments”
The important role of the anterior cruciate ligament with regard to knee stability, physiologic kinematics and proprioception are unquestioned. Thus, various efforts have been made to retain the anterior cruciate ligament during total knee arthroplasty. Neither of the existing implantation techniques, such as bicruciate retaining prostheses and implantation of two unicondylar prostheses, have been successful because of concept-specific problems as well as general difficulties with implant fixation.
Dr. Andrej Nowakowski at the Osteoarthritis Research Center invented and generated a new transversal support tibial plateau concept. It is a prosthesis of two individual joint surfaces reinforced beneath the articular line by joint surface supports and buttressed by a single transversal support. This configuration, allowing retention of both cruciate ligaments, should provide good bony fixation and ensure long term alignment of the individual joint surfaces.
For cement removal in revision arthroplasty”
In revision of cemented total arthroplasty, complete removal of the remaining intramedullary cement mantle remains a challenging task, always fraught with the risk of extensive loss of substance as well as perforation or fracture of the remaining bone stock. By the use of the new Universal Medullary Drill System, invented by Dr. Andrej Nowakowski, safe and complete cement removal was performed successfully both in artificial bone and in real bone preparations under avoidance of perforation or fracture of the preparations.
The first adoption of the theoretical approach of guided drilling for intramedullar cement removal is promising. In order to be well achievable, further development should aim the following :
• efficient, safe and complete removal of the cement,
• preservation of bone stock,
• avoidance of perforation and fracture of the cortical bone,
• reduction of the operative radiation exposure,
• reduction of the operation time.
Crutches for Long Term Usage – “The Ulnar-Pro Technology”
Demographic changes result in a higher prevalence of aged people. Therefore, degenerative musculoskeletal diseases such as osteoarthritis, rheumatic diseases or spine disorders are an increasing health burden. The number of individuals requiring permanent medical walking aids such as crutches will increase substantially in the near future. Current available crutches are cheap and highly functional. The focus of conventional crutches purely is on function, they are not designed for long term use. Overuse is associated with skin bruises and pain. Subsequently, a decrease of mobility, a higher risk of falling and a reduced quality of life is reported by the patients.
We develop walking aids in our laboratory allowing long term use of crutches. The “Ulnar protection” technique preserves the ulnar bone, potentially leading to less bruises and less pain. Our prototypes are currently tested in a clinical trial.
Trabecular Metal™ Ankle Interpositional Spacer – „Filling the gap“
In the rare case of an total ankle prosthesis removement, ankle fusion usually is complicated by substantial bone defects. To overcome this problem, Prof. Valderrabano and two colleagues from the United States have developed the Trabecular Metal™ Ankle Interpositional Spacer.
Trabecular Metal™ has physical and mechanical properties of bone and the advanced fixation surface allows the bone naturaly to grow into the device. At the same time, the spacer maintains the height of the ankle joint when primary ankle fusion procedure is performed.
This technique is a clever alternative for allografts. Our center was the first to implant this device in Europe.