Clinical and patient reported outcomes of Vitamin E diffused highly cross-linked polyethylene liner versus moderately cross linked polyethylene liner in total hip arthroplasty: A meta-analysis

Introduction@#In the modern era of Medicine, total hip arthroplasty (THA) is found to last longer than ever before due to the fact that there has been improved bearing surfaces and materials available. Despite these modern approaches, failure caused by polyethylene wear, aseptic loosening, instability and mispositioning and even infection could affect THA survival. In the course of addressing anti-wear characteristics of the conventional polyethylene surface various approaches have been made. To date, there are very limited studies done in which polyethylene liner is better.@*General Objective@#To compare the effects of vitamin E diffused highly cross-linked polyethylene liner versus moderately cross-linked polyethylene liner in THA. @*Methodology@#Meta-analysis research design was used in this study. The primary investigators conducted a comprehensive literature search from Medline, Cochrane Library, PubMed, Elsevier, Google Scholar, Embase and ClinicalTrial.gov as electronic database. All randomized controlled trials comparing the effects of vitamin E diffused highly cross-linked polyethylene liner versus moderately cross-linked polyethylene liner in THA were included in the review. @*Conclusions@#The investigation disclosed no statistical significance between moderately cross-linked polyethylene liner and vitamin E diffused highly cross-linked polyethylene liner in terms of migration, head penetration and wear on mediolateral, longitudinal and anteroposterior axes after 2 and 5 years of undergoing THA. Moreover, the data pertaining to patient reported outcomes and clinical outcomes measure also indicated no statistical significance between moderately cross-linked polyethylene liner and vitamin E diffused highly cross-linked polyethylene liner. This indicates that vitamin E diffused highly cross-linked polyethylene liner is comparable with the conventional moderately cross-linked polyethylene liner. Vitamin E-infused highly cross-linked polyethylene ( VEPE) showed an almost similar stability with regard to the wear rates and the component showed similar stability with that of moderately cross-linked polyethylene liner.

Evaluación costo-efectividad de las prótesis con superficie cerámica-polietileno vs. metal-polietileno para reemplazo articular primario de cadera en Colombia / Cost-Effectiveness of Ceramic-Polyethylene Vs Metal-Polyethylene Bearing for Primary Total Hip Replacement in Colombia

Introducción Existe una diferencia estadísticamente significativa del 1.2% en la tasa de revisión a 15 años a favor de cerámica- polietileno altamente entrecruzado (CP), demostrada en el registro nacional de artroplastia australiano. Nuestro objetivo es evaluar la costo-efectividad entre los pares: cerámica-polietileno altamente entrecruzado (CP) y metal- polietileno altamente entrecruzado (MP) para el pagador en Colombia. Materiales y métodos Se construyó un árbol de decisiones TreeAge Pro® comparando CP vs MP desde la perspectiva del Sistema de Salud Colombiano (SSC). Los parámetros se tomaron de la mejor evidencia disponible, para la efectividad se realizó una revisión sistemática de la literatura y para los costos se usaron tarifas del mercado local. Se determinó la relación de costo-efectividad incremental, asumiendo un horizonte temporal de 15 años y aplicando una tasa de descuento del 5% para costos y efectividad. La incertidumbre fue controlada por un análisis de sensibilidad determinístico y probabilístico. Resultados Para el SSC, con un umbral de 1 PIB per cápita por año de vida ganado ajustado por calidad (AVAC), en adultos llevados a RTC el uso de CP no es costo-efectiva, dado que la efectividad es similar (MP:11,32 AVAC vs CP: 11,36 AVAC) y el costo es tres veces mayor (MP $ 861.826 COP vs CP $ 2.298.090 COP). El análisis de sensibilidad determinístico demuestra que la variable más importante en el resultado es el costo de la cerámica. Discusión Para el SSC el uso rutinario de cabezas de cerámica en RTC no es una estrategia costo-efectiva.

Background There is a statistically significant difference of 1.2% in the revision rate in a 15 year follow in favour of the use of ceramic on highly cross-linked polyethylene (CP) recently described in the Australian National Joint Registry. The purpose of this study is to compare the cost-effectiveness of CP implants and metal-on-highly cross-linked polyethylene (MP) implants in patients undergoing total hip replacement (THR). Materials and methods A TreeAge Pro® decision tree was constructed in order to determine cost-effectiveness between two bearing surfaces: CP or MP from the perspective of the Colombian Health Care System (CHCS). The model parameters where taken from the best available evidence. For the effectiveness, a systematic review of the literature was performed, and costs were taken from local market rates. The incremental cost-effectiveness ratio was determined assuming a time horizon of 15 years, and a discount rate of 5% was used for costs and effectiveness. Cost-effectiveness uncertainty was controlled with deterministic and probabilistic sensitivity analysis. Results For the CHCS, with a 1PIB per capita threshold adjusted per QALY in adults undergoing (THR), the use of a CP implant is not cost-effective, given that the effectiveness is similar (11.32 QALY for MP vs 11.36 QALY for CP), and the cost is three times higher (MP $ 861.826 COP vs CP $ 2.298.090 COP). The deterministic sensitivity analysis showed that the most important variable in the results is the ceramic cost. Discussion for the CHCS the routine use of ceramic-highly cross-linked polyethylene bearing surface in a THR is not a cost-effective strategy.

Results of Total Hip Arthroplasty with 36-mm Metallic Femoral Heads on 1st Generation Highly Cross Linked Polyethylene as a Bearing Surface in Less than Forty Year-old Patients: Minimum Ten-year Results / 대한고관절학회지

PURPOSE: We evaluated long-term clinical and radiographic results in patients underwent primary total hip arthroplasty (THA) using 36-mm metallic femoral head and 1st generation highly cross-linked polyethylene among patients aged 40 years and less, with minimum 10 years follow-up. MATERIALS AND METHODS: We retrospectively reviewed 20 hips underwent primary THA by one hip surgeon using 36-mm femoral head and 1st generation highly cross-linked polyethylene from 2004 to 2006. Mean follow up was 131.55 months. Clinical follow-ups included functional measurements. And we evaluated post operative complications, prosthesis loosening, failure, and osteolysis. For radiologic evaluations, together with position of acetabular cup at 6 weeks later of postoperation, we separately calculated the penentrations of femoral heads into polyethylene liners during postoperation and one year later check-ups, and during one year later check-ups and final check-ups. Polywear pro3D 5.10 software was used to measure penetrations of femoral head. RESULTS: Mean acetabular cup inclination and anteversion were 49.02° and 10.19°, respectively. Mean thickness of the polyethylene liner at 45° was 6.44 mm. There were no major complications such as implant loosening or osteolysis, and one case of dislocation occurred. Average modified Harris hip score at final follow-up was 91, and Merle d'Aubigne and Postel scores 15 were or over. Average femoral head penetration of bedding wear was 0.170±0.039 mm/year. Steady-state wear rates was 0.059±0.006 mm/year. CONCLUSION: Results of THA with 36-mm metallic femoral heads on 1st generation highly cross linked as a bearing surface in less than 40 year-old patients were satisfactory.

Results of Primary Total Hip Arthroplasty Using 36 mm Femoral Heads on 1st Generation Highly Cross Linked Polyethylene in Patients 50 Years and Less with Minimum Five Year Follow-up / 대한고관절학회지

PURPOSE: We evaluated the clinical and radiographic midterm results of primary total hip arthroplasty (THA) using a 36 mm diameter femoral head on 1st generation highly cross-linked polyethylene (HXLPE) in patients 50 years and less with minimum five year follow-up. MATERIALS AND METHODS: We retrospectively reviewed 31 patients (41 hips) aged 50 years and less underwent primary THA with a 36 mm diameter femoral head on HXLPE between 2004 and 2010. Clinical follow-ups included specific measurements like modified Harris hip scores (HHS) and Merle d'Aubigne and Postel score. For radiologic evaluations, together with position of acetabular cup at six weeks later of postoperation, we separately calculated the penentrations of femoral head into polyethylene liners during postoperation and one year later check-ups, and during one year later check-ups and final check-ups. RESULTS: There were no major complications except for one case of dislocation. Average modified HHS at final follow-up was 88 (81-98), and Merle d'Aubigne and Postel scores were more than 15. Mean acetabular cup inclination and anteversion were 45.81°(36.33°-54.91°) and 13.26°(6.72°-27.71°), respectively. Average femoral head penetration of steady-state wear rate determined using radiographs taken at one-year postoperatively and at latest follow-up was 0.042±0.001 mm/year. CONCLUSION: Based on minimum 5 years clinical results, we think 36 mm metal head coupling with HXLPE as the good alternate articulation surface when planning THA for patients aged 50 years and less.

A Liner Breakage in Total Hip Arthroplasty after Using 1st Generation Highly Cross Linked Polyethylene Mated against 36-mm Metal Head: A Case Report / 대한고관절학회지

It has been known the highly cross linked polyethylene (HXLPE) has an advantage of improved wear rate. However, the alteration in mechanical properties such as decreased tensile yield and fatigue strength make concerns about fragility of HXLPE. We experienced a case of HXLPE breakage. But, this case of liner breakage happened although patient belonged to normal BMI and proper acetabular cup position so called "safe zone" on radiographs. So, we report this case with reference review.

Total Hip Arthroplasty Using Metal Head on a Highly Cross-linked Polyethylene Liner / 대한고관절학회지

PURPOSE: This retrospective study was performed to evaluate the clinical results and measure polyethylene liner wear in total hip arthroplasty (THA) with highly cross-linked polyethylene. MATERIALS AND METHODS: Except for patients who had died or were unable to have follow-up at least 2 years, 60 of 78 hips that underwent THA were included this study. The mean age was 64.5 years (range, 25-81 years) and the mean body mass index (BMI) was 23.0 kg/m2 (18.1-32.3 kg/m2). Diagnosis at the time of the operation was osteonecrois of the femoral head in 28 hips, primary osteoarthritis in 14, hip fracture in 13, and other diseases in 5. The mean follow-up period was 3.8 years (2.1-7.1 years). Harris hip score (HHS) was reviewed before THA and at the last follow-up. On the anteroposterior pelvic radiographs, acetabular cup inclination and ante-version were also measured. The annual linear wear rate was measured using Livermore's method on the radiographs. RESULTS: The mean HHS was 60.1 (28-94) before operation and 90.4 (47-100) at the last follow-up. In the immediate post-operation, the average inclination and anteversion angles of the acetabular cups were 46.3degrees (standard deviation, +/-6.7degrees) and, 21.4degrees(+/-10.1degrees) respectively. The mean of the annual linear polyethylene wear was 0.079 mm/year (0.001-0.291 mm/year). Age, gender and BMI were not statistically related to linear polyethylene wear but the period of follow-up and the acetabular cup's inclination showed significant negative and positive correlation respectively. CONCLUSION: The wear rate of a highly cross-linked polyethylene was shown to correlate negatively with duration of follow-up. However, our study was based on a short-term follow-up, so a long-term follow-up study is necessary in the future.

Results of Primary Total Hip Arthroplasty with 36-mm Femoral Heads on Highly Cross-linked Polyethylene-Minimum Seven-years Follow-up / 대한고관절학회지

PURPOSE: We evaluate the clinical and radiographic midterm results of primary total hip arthroplasty (THA) using a 36 mm diameter femoral head on highly cross-linked polyethylene (minimum 7-year follow-up). MATERIALS AND METHODS: We retrospectively reviewed 73 patients (74 hips) that underwent primary THA with a 36 mm diameter femoral head on highly cross-linked polyethylene between July 2004 and February 2007. Clinical follow-ups included specific measurements like modified Harris hip scores (HHS) and Merle d'Aubigne and Postel score. For radiologic evaluations, together with position of acetabular cup at 6 weeks later of post-operation, we separately calculated the penentrations of femoral heads into polyethylene liners during post-operation and one year later check-ups, and during one year later check-ups and final check-ups. RESULTS: There were no complications except for one case of dislocation. Average modified HHS at final follow-up was 88+/-7.5 (range, 81-96), and Merle d'Aubigne and Postel scores were more than 15 (range, 15-18). Mean acetabular cup inclination and anteversion were 50.1degrees(range, 35degrees-58degrees) and 23.6degrees(range, 5degrees-38degrees), respectively. Average femoral head penetration during the first postoperative year was 0.071+/-0.034 mm/year, and steady-state wear rate determined using radiographs taken at one-year postoperatively and at latest follow-up was 0.051+/-0.022 mm/year. Average femoral head penetration during entire follow-ups was 0.058+/-0.013 mm/year. CONCLUSION: Primary THA with a large diameter femoral head on highly cross-linked polyethylene was found to produce the results comparable to previous in vitro laboratory hip simulation studies. And we also find out good scores in terms of patient's functionality.