Novel concept of a modular hip implant could contribute to less implant failure in THA: a hypothesis

Abstract

BackgroundThe modularity in total hip arthroplasty (THA) allows orthopaedic surgeons for an exact reconstruction of hip biomechanical parameters especially in revision and tumor arthroplasty. Modular structured femoral stems using taper junctions showed increased implant breakage in the recent past.Presentation of the hypothesisWe hypothesize that a novel modular stem-neck-interface leads to less implant breakage compared to conventional femoral stems.Testing of the hypothesisFor this purpose, a novel modular femoral stem for THA was to design and manufacture. Therefore, three different variants of interface mechanisms were developed that enable a simple connection between the stem and the neck modules and allow for intra-operatively adjustment. Three prototypes A, B and C were manufactured and subsequently dynamic fatigue (ISO 7206–6) and body donor tested.Implication of the hypothesisModularity in THA is mainly applied in THA as well as in revision and tumor arthroplasty. Modular implants are barely used because of the high risk of breakage. Another risks in this context are taper fretting, corrosion and disconnection. With the novel design, it should be possible to detach the stem and neck module intra-operatively to adapt the anatomical situation. The novel coupling mechanism of the rotating interface seems to be the most suitable for a secure stem-neck connection and is characterized by good intraoperative handling.

Three-dimensional models increase the interobserver agreement for the treatment of proximal humerus fractures

“…Although the prevalence of proximal humerus fractures is relevant and growing worldwide [ 20 ], we still have problems with diagnosis and definitions about the best treatment [ 2 , 3 , 7 , 8 , 13 , 21 – 28 ]. With these findings presented here, we believe that surgeons, while still in training, are influenced by tactile rather than exclusively visual aspects to understand shoulder fractures.…”

“…The classifications proposed by Charles Neer, 1970 [ 5 ] and the AO / OTA group - Arbeit Gemeinschaft für Osteosynthesefragen [ 6 ], the most widespread and used worldwide, were not able to find a relevant reproducibility for diagnosis of proximal humerus fractures [ 21 – 23 ]. It seems logical, therefore, that the best choice to treat patients has uncertainties [ 2 , 3 , 13 ]. Handoll et al [ 2 ] state that there is not enough evidence that surgical treatments are superior to conservative ones.…”

“…Despite being a routine in orthopedic medical practice, understanding different patterns of shoulder fractures, the number associated injuries, the classification, and proposed treatment remains uncertain. The diversity of treatments has been discussed as a relevant subject in studies involving traumatology and shoulder surgery [ 1 – 3 ].…”

“…The widespread and well-known classifications are the Charles Neer, in 1970 [ 4 , 5 ] and the AO/OTA group - Arbeit Gemeinschaft für Osteosynthesefragen [ 6 ]. However, several studies demonstrate low agreement for intra and interobserver reproducibility and the correlation between the diagnosis, classification, and therapeutic proposal involving these lesions [ 2 , 3 , 7 , 8 ]. These limitations encourage new studies to improve the classifications known or even alternative diagnostic methods.…”

Global prevalence and reasons for case cancellation on the intended day of surgery: A systematic review and meta-analysis

“…Cancellation of operation on the intended day of surgery affects the efficiency of OR, reduces utilization of OR time and waste resources which incur a significant financial loss for the patient hospital and health care cost of a country at large [ [2] , [3] , [4] , [5] , [6] , [7] , [9] , [10] , [11] , [12] , [13] , [14] , [15] , [16] , [17] ].…”