Intraoperative Fluoroscopy Allows the Reliable Assessment of Deformity Correction during Periacetabular Osteotomy.

We aimed to determine the accuracy and reliability of measures characterizing anterior, lateral, and posterior acetabular coverage on intraoperative fluoroscopic images compared to postoperative radiographs when performing periacetabular osteotomies (PAOs). A study involving 100 PAOs was initiated applying a standardized intraoperative imaging protocol. Coverage was determined by the lateral center edge angle (LCEA), the Tönnis angle (TA), and the anterior and posterior wall index (AWI, PWI). An intraclass correlation coefficient (ICC) model was used to assess interrater (ICC (3,2)) and intrarater (ICC (2,1)) reliability. The ICC (2,2) between analyses obtained from intraoperative fluoroscopy and postoperative radiographs and the corresponding 95% confidence interval (CI) were determined and complemented by Bland-Altman analysis, the mean difference, and 95% limits of agreement (LOA). The ICCs were 0.849 for the LCEA (95% CI 0.783-0.896), 0.897 for the TA (95% CI 0.851-0.930), 0.864 for the AWI (95% CI 0.804-0.907), and 0.804 for the PWI (0.722-0.864). The assessed interrater reliability was excellent except for the AWI, which was graded good (ICC = 0.857, 95% CI 0.794-0.902). Interrater agreement was generally good and fair for the AWI (ICC = 0.715, 95% CI 0.603-0.780). For each postoperative radiograph, interrater reliability was good with ICCs ranging from 0.813 (TA) to 0.881 (PWI). Intrarater reliability was good for all measurements and excellent for the preoperative TA (ICC = 0.993, 95% CI 0.984-0.997) and PWI (ICC = 0.954, 95% CI 0.919-0.97). In summary, we confirm the validity and reliability of intraoperative fluoroscopy as an alternative imaging modality to radiography to evaluate acetabular fragment orientation during PAO. We affirm the LCEA and TA as precise measures for lateral head coverage, and show the suitability of the AWI and PWI to steadily assess acetabular version.

Function and activity after minimally invasive total hip arthroplasty compared to a healthy population.

PURPOSE: The aim of the present study was to compare the daily activity and functionality in a patient cohort 12 months after total hip arthroplasty (THA) using a direct anterior approach with a healthy non-operated control population. METHODS: Sixty-four patients who underwent THA and 59 healthy individuals (control) were assessed regarding their daily activity and joint functionality utilizing the Harris hip score (HHS), the extra short musculoskeletal functional assessment questionnaire (XSFMA), the Short Form 36 (SF-36) health survey and a Stepwatch™ Activity Monitor (SAM). Post-operative x-ray images after THA were analysed regarding inclination and stem positioning. RESULTS: Twelve months after surgery, the average HHS showed no significant difference between both groups equalling 90.7 points in the THA patient group and 90.8 in the healthy volunteer group. The XSFMA functional index scores were 11.0 (THA) and 5.0 (control) while the bother index summed up to a score of 15.3 (THA) and 7.6 (control) respectively thus differing significantly (p < 0.001). Daily activity equalled 4227 (THA) and 4687 (control) load cycles per day (p = 0.327) while a number of 5658 (THA) and 6417 (control) steps per day (p = 0.011) was recorded. The SF-36 physical component scores were 47.3 (THA) and 50.6 (control) points while the psychometric properties added up to a score of 56.1 (THA) and 55.9 (control). The physical component was determined to be significantly different (p < 0.001) whereas no statistically significant difference could be shown for the psychometric properties (p = 0.511). The radiographic analysis revealed an average cup inclination of 39.9° without signs of migration. Stem positioning was neutral in 53% of all cases while 36% were graded varus and 11% valgus. CONCLUSION: In summary, our short-term results show an activity, functionality and quality of life for patients one year after THA comparable to healthy control individuals.

How smart do biomaterials need to be? A translational science and clinical point of view.

Over the last 4 decades innovations in biomaterials and medical technology have had a sustainable impact on the development of biopolymers, titanium/stainless steel and ceramics utilized in medical devices and implants. This progress was primarily driven by issues of biocompatibility and demands for enhanced mechanical performance of permanent and non-permanent implants as well as medical devices and artificial organs. In the 21st century, the biomaterials community aims to develop advanced medical devices and implants, to establish techniques to meet these requirements, and to facilitate the treatment of older as well as younger patient cohorts. The major advances in the last 10 years from a cellular and molecular knowledge point of view provided the scientific foundation for the development of third-generation biomaterials. With the introduction of new concepts in molecular biology in the 2000s and specifically advances in genomics and proteomics, a differentiated understanding of biocompatibility slowly evolved. These cell biological discoveries significantly affected the way of biomaterials design and use. At the same time both clinical demands and patient expectations continued to grow. Therefore, the development of cutting-edge treatment strategies that alleviate or at least delay the need of implants could open up new vistas. This represents the main challenge for the biomaterials community in the 21st century. As a result, the present decade has seen the emergence of the fourth generation of biomaterials, the so-called smart or biomimetic materials. A key challenge in designing smart biomaterials is to capture the degree of complexity needed to mimic the extracellular matrix (ECM) of natural tissue. We are still a long way from recreating the molecular architecture of the ECM one to one and the dynamic mechanisms by which information is revealed in the ECM proteins in response to challenges within the host environment. This special issue on smart biomaterials lists a large number of excellent review articles which core is to present and discuss the basic sciences on the topic of smart biomaterials. On the other hand, the purpose of our review is to assess state of the art and future perspectives of the so called "smart biomaterials" from a translational science and specifically clinical point of view. Our aim is to filter out and discuss which biomedical advances and innovations help us to achieve the objective to translate smart biomaterials from bench to bedside. The authors predict that analyzing the field of smart biomaterials from a clinical point of view, looking back 50 years from now, it will show that this is our heritage in the 21st century.