The Ideal Total Hip Replacement Bearing Surface in the Young Patient: A Prospective Randomized Trial Comparing Alumina Ceramic-On-Ceramic With Ceramic-On-Conventional Polyethylene: 15-Year Follow-Up

2018 ◽  
Vol 33 (6) ◽  
pp. 1752-1756 ◽  
Author(s):  
Amit Atrey ◽  
Jesse I. Wolfstadt ◽  
Nasir Hussain ◽  
Amir Khoshbin ◽  
Sarah Ward ◽  
...  
Children ◽  
2021 ◽  
Vol 8 (10) ◽  
pp. 858
Author(s):  
Giovanni Trisolino ◽  
Stefano Stallone ◽  
Francesco Castagnini ◽  
Barbara Bordini ◽  
Monica Cosentino ◽  
...  

Background: total hip replacement (THR) is a rare surgical option in children and adolescents with disabling hip diseases. The aim of this study is to report results from a retrospective cohort of patients aged 18 years or less who underwent cementless Ceramic-on-Ceramic (CoC) THR at a single institution, investigating clinical and radiographic outcomes, survival rates, and reasons for revision of the implants. Materials and methods: we queried the Registry of Prosthetic Orthopedic Implants (RIPO) to identify all children and adolescents undergoing THR between 2000 and 2019 at a single Institution. Inclusion criteria were patients undergoing cementless CoC THR, aged less than 18 years at surgery, followed for at least 2 years. Sixty-eight patients (74 hips) matched all the inclusion criteria and were enrolled in the study. We assessed the clinical and radiographic outcomes, the rate of complications, the survival rate, and reasons for revision of the implants. Results: The mean follow-up was 6.6 ± 4.4 years (range 2–20). The most frequent reason for THR was post-traumatic or chemotherapy-induced avascular necrosis (38%). The overall survival rate of the cohort was 97.6% (95% CI: 84.9–99.7%) at 5 years of follow-up, 94.4% (95% CI: 79.8–98.6%) at 10 years and 15 years of follow-up. Two THR in two patients (2.7%) required revision. With the numbers available, Cox regression analysis could not detect any significant interaction between preoperative or intraoperative variables and implant survivorship (p-value 0.242 to 0.989).” The average HOOS was 85 ± 14.3 (range 30.6–100). Overall, 23 patients (48%) reported excellent HOOS scores (>90 points), 21 patients (44%) reported acceptable HOOS scores (60–90 points) while 4 patients (8%) reported poor outcomes (<60 points). Twenty-one patients (43%) were regularly involved into moderate- to high-intensity sport activities (UCLA ≥ 6). Conclusions: Cementless CoC THR is a successful procedure in children and teenagers, having demonstrated high implant survivorship and low rates of complications and failure. A meticulous preoperative planning and implant selection is mandatory, to avoid implant malposition, which is the main reason of failure and revision in these cases. Further studies are needed to assess the impact of the THR on the psychosocial wellbeing of teenagers, as well as risks and benefits and cost-effectiveness in comparison to the hip preserving surgical procedures.


Author(s):  
Mark Sidebottom ◽  
D. G. Allan ◽  
Manish Paliwal

Ceramic-on-Ceramic (CoC) bearings are an ideal choice for a total hip replacement because of the ceramic bearings’ longer wear life than Metal-on-Metal or Metal-on-Polyethylene bearings. Friction-induced squeaking has been reported in 1–10% of patients who have a ceramic-on-ceramic total hip replacement, which is a subject of annoyance. Many mechanisms have been proposed to address the squeaking phenomena in CoC hip replacements, but there is no consensus among researchers on the root cause behind the squeaking of hip implants. The goal of this study was to investigate the possible factors attributing to the hip squeak, and understand the underlying phenomenon based on the coupling stiffness of the bearing surface. Boundary conditions for the CoC hip bearing to produce audible noise were also identified. An explanted Stryker Trident CoC hip bearing that had been removed due to squeaking was analyzed visually and by computer simulation. Grey marks on the femoral head of the implant showed material transfer of titanium alloy onto the alumina head. Using modal analysis, the natural frequencies of all the components of the implant were determined. Random vibration analysis was conducted to identify the ideal boundary conditions for the CoC hip bearing. The results from the modal analysis and calculated stiffness and damping coefficients were used in the mathematical two degree-of-freedom (DOF) model to calculate the velocity and position of the two masses in the system. State-Space plots of the parametric analysis were used to evaluate the stability of the system. Mathematical Analysis involved the investigation of the role of the frictional stick-slip phenomenon of the metal shell and ceramic liner on squeal. The size of the limit cycle provides an indication of the degree of severity of a noisy condition. With only metallic shell affixed to the acetabulum constrained, the modal natural frequency was 3600 Hz which was very close to the free vibration results of the bearing. The Power Spectral Densities displayed the audible frequencies at 11.4 kHz. The limit cycle plots show that a variation in coupling contact stiffness has an influence on the behavior/stability of the system. The study underscored the relevance of material transfer on the bearing surface using the mathematical analysis by varying the coupling stiffness of the bearing surface. In addition, random vibration analysis in conjunction with the parametric analysis identified the ideal boundary condition to produce the squeal frequencies as observed by others.


Sign in / Sign up

Export Citation Format

Share Document