Different types of highly cross-linked polyethylene (HXLPE) have been introduced widely in acetabular cups in hip prostheses to reduce the incidence of wear debris-induced osteolysis. Also, we reported that HXLPE cups with 28-mm
Introduction. Wear of the ultra high molecular weight polyethylene (UHMWPE) cup and the resulting loosening has been shown to limit the long-term results of the Charnley low-frictional torque arthroplasty (LFA). Factors affecting wear rates have been studied: level of patient activity, effective roughness of the stainless steel head, impingement and the possible variations in wear characteristics of UHMWPE. Since patients' activity level cannot be predicted or modified, alternative materials were examined. Methods and Results. The Charnley 22.225 mm diameter head of
Local concentration of antibiotic at the site of infection is a major parameter for its efficiency. However, bone diffusion is poor leading either to their non-use (ex: gentamicin) or the use of high concentration (ex: vancomycin). Local administration could optimize their local concentration combined with lower side effects. We report the clinical experience and pharmacological results of an antibiotic loaded porous alumina used to replace infected bone in 4 patients. Two patients had a destroyed sternum following mediastinitis; one presented a femoral chronic osteomyelitis due to MRSA and one had an infected ankle arthroplasty. The ceramic was loaded with gentamicin in three cases and vancomycin for the ankle infection. Local dosages thanks to Redon's drain and blood samples were performed. Loading was done to protect the device while implanted in an infected area and was combined with conventional antibiotic therapy.Aim
Method
The fourth generation ceramic, in which zirconia is incorporated into the alumina matrix, was developed to reduce the risk of ceramic fractures. The purpose of this study was to evaluate the survivorship, clinical and radiographic results, and bearing-related failures associated with total hip arthroplasty using zirconia-toughened alumina ceramic-on-ceramic bearings over a minimum follow-up of 5 years. We retrospectively analysed 135 patients (151 hips) who underwent cementless total hip arthroplasty using zirconia-toughened alumina ceramic-on-ceramic bearings. There were 58 men and 77 women with mean age of 55.9 years (range, 20 to 82 years) at index surgery. Acetabular and femoral components were cementless in all hips. A 36 mm head was used in 81 of 151 hips and a 32 mm head was used in 70 hips with smaller acetabular shells. The mean duration of follow-up was 6.1 years (range, 5 to 6.8 years).Purpose
Materials and methods
The optimal bearing for hip arthroplasty is still a matter of debate. in younger and more active patients ceramic-on-polyethylene (CoP) bearings are frequently chosen over metal-on-polyethylene (MoP) bearings to reduce wear and increase biocompatibility. However, the fracture risk of ceramic heads is higher than that of metal heads. This can cause serious issue, as ceramic fractures pose a serious complication often necessitating major revision surgery – a complication more frequently seen in ceramic-on-ceramic bearings. To date, there are no long-term data (> 20 years of follow-up) reporting fracture rates of the ceramic femoral heads in CoP bearings. We retrospectively evaluated the clinical and radiographic results of 348 cementless THAs treated with 2nd generation Biolox® Al2O3 Ceramic-on-Polyethylene (CoP) bearings, which had been consecutively implanted between January 1985 and December 1989. At implantation the mean patient age was 57 years. The cohort was subsequently followed for a minimum of 20 years. At the final follow-up 111 patients had died, and 5 were lost to follow-up (Fig. 1). A Kaplan-Meier survivorship analysis was used to estimate the cumulative incidence of ceramic head fractures over the long-term.Introduction
Patients and Methods
Young patients (< 50 years old) have been reported to have a higher risk of revision following total hip arthroplasty (THA) than older patient cohorts, possibly to due higher activity, a higher incidence of deformity and greater probability of prior surgery. Ceramic-on-ceramic bearing surfaces have been proposed for use in young and active individuals due to their low wear, low risk of adverse biologic reaction, and long-term survivorship. We assessed the clinical results and long-term survivorship of uncemented ceramic-on-ceramic THA in a young patient population. Between August 1999 and December 2007, 220 total hip arthroplasties in 191 patients under 50 years of age at the time of surgery were performed using alumina ceramic-ceramic bearings as part of a prospective, non-randomized study. All patients received uncemented acetabular components with flush-mounted acetabular liners using an 18 degree taper, and uncemented femoral components. The average patient age at the time of surgery was 42.1 ±7.2 years (range: 17.4 years to 49.9 years), and the average time to follow-up was 10.1 ±2.4 years (range: 4.2 years to 15.2 years). We evaluated implant-related complications and performed Kaplan-Meier analyses to determine survivorship of the THA components with revision for any reason as the endpoint.INTRODUCTION
METHODS
Young patients have been reported to have a higher risk of revision following total hip arthroplasty than older cohorts. This was attributed to the higher activity level which led to increased wear, osteolysis, and component fracture. We prospectively assessed the clinical results, wear and osteolysis, the incidence of squeaking, and the survivorship of ceramic on ceramic THA in patients younger than 50 years (mean age of 42 [18–50] years). The series included 425 THAs in 370 patients with 368 hips followed for a minimum of 2 years (mean 7.1 years, range 2–14 years). All patients received uncemented acetabular components with flush-mounted acetabular liners using an 18 degree taper. No osteolysis was observed in any uncemented construct. There was osteolysis around one loose cemented femoral component. The survivorship for reoperation for implant revision was 96.7%. There were only two acetabular liner fractures (0.47%) and one femoral head fracture (0.24%). Two of the three fractures involved a fall from a significant height. There were no hip dislocations. Five patients (1.17%) noted rare or occasional squeaking. None had reproducible squeaking. In summary, the current study shows that ceramic-on-ceramic THAs in the young patient population are extremely reliable with a very low revision rate and an absence of wear-induced osteolysis. In addition, it shows that both bearing fracture in this young patient population typically occurs with polytrauma and squeaking issues that have been raised relative to ceramic bearings occur very rarely with the flush-mounted ceramic liner design used in this study.
Introduction. The success of total hip arthroplasty has meant its indications have been extended to the younger more active patient. Due to the higher activity levels and increased demands of these patients, revision rates have been traditionally higher than when compared to older patients [1]. Ceramic on ceramic bearings may offer a viable long term solution as manufacturing methods have evolved resulting in improved mechanical properties, particularly of third and fourth generation ceramics. We report the outcome of primary cementless, alumina-on-alumina hip arthroplasty with a minimum 10 year follow up in 110 patients under the age of 55 years of age at time of surgery. Methods. A series of 120 consecutive total hip arthroplasties in 110 patients were performed between June 1997 and February 1999 by the two senior authors. All patients had an Osteonics ABC acetabular component and SecurFit or SecurFit Plus femoral component (Stryker Orthopaedics, Mahwah, NJ) with an
Key Points:. Historically, 22.25, 26, 28, or 32 mm metal femoral heads were used in primary total hip arthroplasty, but innovations in materials now permit head sizes 36 mm or larger. Stability and wear of primary total hip arthroplasty are related to the diameter and material of the femoral head. Larger diameter femoral heads are associated with increased joint stability through increases in arc range of motion and excursion distance prior to dislocation. Fixation of the acetabular component may be related to the size of the femoral head, with increased frictional torque associated with large diameter heads and certain polyethylene. Linear wear of highly crosslinked polyethylenes seems unrelated to femoral head diameter, but larger heads have been reported to have higher volumetric wear. Mechanically assisted crevice corrosion at the connection between the modular femoral head and neck may be associated with the femoral head size and material. Cobalt chromium alloy,
INTRODUCTION. Squeaking after total hip replacement has been reported in up to 10% of patients. Some authors proposed that sound emissions from squeaking hips result from resonance of one or other or both of the metal parts and not the bearing surfaces. There is no reported in vitro study about the squeaking frequencies under lubricated regime. The goal of the study was to reproduce the squeaking in vitro under lubricated conditions, and to compare the in vitro frequencies to in vivo frequencies determined in a group of squeaking patients. The frequencies may help determining the responsible part of the noise. METHODS. Four patients, who underwent THR with a Ceramic-on-Ceramic THR (Trident(r), Stryker(r)) presented a squeaking noise. The noise was recorded and analysed with acoustic software (FMaster(r)). In-vitro 3
Aim.
One of serious issues in total hip arthroplasty (THA) is the osteolysis which results in aseptic loosening caused by the wear particles from a polyethylene (PE) acetabular cup. In addition, oxidation degradation of PE cup resulting in the fracture or the severe wear caused by the reduction of mechanical properties in vivo is also the issue. The oxidation degradation is considered to be induced by residual free radicals generated by gamma-ray irradiation for cross-linking to reduce wear or for sterilization. In this study, (1) wear property, (2) oxidation degradation of retrieved PE and highly cross-linked PE (CLPE) cups against
Introduction. From a tribological point of view and clinical experience, a ceramic-on-ceramic bearing represents the best treatment option after rare cases of ceramic component fracture in total hip arthroplasty (THA). Fractured ceramic components potentially leave small ceramic fragments in the joint capsule which might become embedded in PE acetabular liners. Purpose. This in vitro study compared for the first time the wear behaviour of femoral ball heads made of ceramic and metal tested with PE liners in the presence of ceramic third-body debris. The contamination of the test environment with third-body ceramic debris, insertion of ceramic fragments into the PE liners and implementation of continuous subluxation simulated a worst-case scenario after revision of a fractured ceramic component. Materials and Methods. Ceramic femoral ball heads (ϕ 32 mm) made of alumina matrix composite (AMC; BIOLOX® delta, CeramTec, Germany) were tested in combination with PE and cross-linked liners and compared to metal femoral ball heads (CoCrMo) of the same diameter. All PE liners were fixed into Ti-6Al-4V metal shells by conical fixation as intended for clinical use. The tests were performed based on ISO 14242-1 utilizing a hip simulator (EndoLab, Germany).
Introduction.
INTRODUCTION. In theory, Finite Element Analysis (FEA) is an attractive method for elucidating the mechanics of modular implant junctions, including variations in materials, designs, and modes of loading. However, the credence of any computational model can only be established through validation using experimental data. In this study we examine the validity of such a simulation validated by comparing values of interface motion predicted using FEA with values measured during experimental simulation of stair-climbing. MATERIALS and METHODS. Two finite element models (FEM) of a modular implant assembly were created for use in this study, consisting of a 36mm CoCr femoral head attached to a TiAlV rod with a 14/12 trunnion. Two head materials were modelled: CoCr alloy (118,706 10-noded tetrahedral elements), and
Aim. To study the efficacy of Hydroxyapatite (HAC) Ceramic Coated hip arthroplasty. Is it suitable for the younger patient?. Methods. This series of 2390 primary HAC hip arthroplasties has been studied for up to 21 years. (569 hips over 10 years including 98 hips over 15 years) Patients are assessed by Harris Hip Score and plain X-ray. The prosthesis consists of a fully coated stem and a fully coated acetabulum. A ceramic head articulates with an acetabular liner which is either plastic (UHMW polythene) or ceramic. No cement is used. HA coated implants are physiologically fixed to cancellous bone by a process of osseointegration. Other uncemented implants are pathologically fixed by fibrous scar tissue. These two methods of fixation should be considered separately and not combined as ‘uncemented’. Results. Aseptic loosening in this series is 0.63 %. The revision rate in this series for all reasons is only 3.5%. Harris Hip Score (HHS) demonstrates excellent medium to long term results in 97% of cases (i.e. up to 20 years). Poor HHS results (36 cases: 1.51%) are mostly related to medical or other joint problems. HA fixation will outlast some of the components and wear in polythene acetabular liners can be a problem after 15 years. A sub-group of 629 hips using
Background/Purpose. Total hip arthroplasties (THAs) with ceramic bearings are widely performed in young, active patients and thus, long-term outcome in these population is important. Moreover, clinical implication of noise, in which most studies focused on ‘squeaking’, remains controversial and one of concerns unsolved associated with the use of ceramic bearings. However, there is little literature regarding the long-term outcomes after THAs using these contemporary ceramic bearings in young patients. Therefore, we performed a long-term study with a minimum follow-up of . 1. 5 years after THAs using contemporary ceramic bearings in young patients with osteonecrosis of the femoral head (ONFH) less than fifty. Materials and Methods. Among sixty patients (71 hips) with a mean age of 39.1 years, 7 patients (7 hips) died and 4 patients (4 hips) were lost before 15-year follow-up. The remaining 60 hips were included in this study with an average follow-up period of 16.3 years (range, 15 to 18). All patients underwent cementless THA using a prosthesis of identical design and a 28-mm third-generation alumina head by single surgeon. The clinical evaluations included the modified Harris hip score (HHS), history of dislocation and noise around the hip joint: Noise was classified into squeaking, clicking, grinding and popping and evaluated at each follow-up. Snapping was excluded through physical examination or ultrasonography. Radiographic analysis was performed regarding notching on the neck of femoral component, loosening and osteolysis. Ceramic fracture and survivorship free from revision were also evaluated. Results. The mean Harris hip score improved from 55.3 to 95.5 points (range, 83 to 100) at the time of the final follow-up. Seventeen patients (34.7%) reported noise around the hip joint: “squeaking” in one and “clicking” in 16 patients. Notching on the neck of femoral component suggesting impingement between neck and ceramic liner was demonstrated in 9 hips (15%) at average of 6.9 years postoperatively and located at 2 to 3.5 mm distal to edge of ceramic head. Although no chip fracture of ceramic ‘liner’ occurred, notching was associated with “clicking” sound (p<0.01). One patient who reported clicking sound underwent a revision THA because of ceramic ‘head’ fracture. Loosening, osteolysis or dislocation was not observed in any hip and survivorship free from revision at 5 years was 98%. Conclusion. Cementless THAs using 28-mm contemporary
Introduction. Ceramic total knee arthroplasty (TKA) was introduced as a new-generation of knee prostheses in clinical practice, and are expected to reduce polyethylene wear due to its resistance to abrasion and lubrication. In 1992, we developed a cruciate retaining LFA-I total knee prosthesis (KYOCERA Medical Co., Japan), which comprises an
Two types of ceramic materials currently used in total hip replacements are third generation hot isostatic pressed (HIPed)
Despite 46 years clinical experience with ceramic-on-ceramic (COC) hip bearings, there is no data on what constitutes a successful long-term wear performance. There have been many studies of short-term failures (Dorlot, 1992; Nevelos, 2001, Walters, 2004). One retrieval study using optical-CMM technology (OCM) documented volumetric wear-rates ranging up to 7mm. 3. /year on femoral heads (Esposito 2012). It was noted that 83% of these revisions showed stripe damage within 3–4 years. The supposition would appear to be that these were bearing-related failures. Our selected COC case for this study was particularly interesting, a female patient having her index surgery performed at age 17 and revised at age 49 (following onset of hip pain). This patient led an active lifestyle, went dancing multiple times per week, and was mother to three children. The 38mm Autophor. TM. THA (left hip) was eventually revised due to the cup painful migrating (Fig. 1: 32-years follow-up). Radiographs showed cup inclination at approximately 19. °. Impingement marks were noted on the CoCr neck and collared stem (Fig. 2). Implant geometry and form factors were analyzed by standard contour measurement (CMM) while SEM and EDS imaging provided wear topography and evidence of metal contaminants. Linear and volumetric wear in head and cup were studied by OCM at Redlux (Southampton, UK). The head's main wear-pattern consisted of two overlapping circular areas (Fig. 3). The narrowest margin made by the wear-pattern was used to define the superior aspect of the head. By light microscopy, the superior main-wear zone covered 1490–1680mm. 2. area while the total bi-lobed area covered larger 2170mm. 2. area. OCM analysis delineated the same bi-lobed appearance of head wear with the superior worn area assessed at 1365mm. 2. The cup revealed a more extensive wear pattern that circumnavigated its surface. The black staining identified by EDS imaging in the cup revealed Co and Cr elements. By OCM technique the head volumetric wear was 179 mm³ and the cup was 214mm. 3. (Fig. 4), i.e. 20% greater than head. Volumetric wear-rate averaged 12.3mm. 3. per year for this pioneering