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In the 1970s, high failure rates of cemented acetabular components, especially in young patients, in the middle- and long-term prompted a search for alternatives. The Mecring was one of the most popular first generation uncemented, threaded cups widely used in the 1980s for arthroplasty of the hip. First generation threaded cups commonly had smooth surface treatment and showed unacceptably high failure rates in the mid-term. In a consecutive series of 209 patients, 221 threaded uncemented acetabular cups with smooth surface treatment (Mecring) had been implanted in combination with one type of uncemented stem. Patients were followed up clinically and radiographically. The mean time of follow-up was 17 (range 15-20) years. In 91 (41%) hips the acetabular component had been revised or was awaiting revision: two hips for infection and 84 (38%) for aseptic loosening. Five hips were awaiting revision. The survival rate for all revisions including hips awaiting revision was 49% (95% CI: 41-57%) at 17 years. These results support the view that smooth, threaded acetabular components do not provide satisfactory long-term fixation and should be abandoned. Patients with these components must be closely monitored as the failure rate remains high in the long-term. [ABSTRACT FROM AUTHOR]

Uncemented, threaded acetabular components with smooth surface treatment were widely used in continental Europe in the 1970s and 1980s for primary total hip arthroplasty (THA). Previously published studies showed high failure rates in the mid-term. In a consecutive series of 116 patients, 127 threaded cups with smooth surface treatment (Weill cup; Zimmer, Winterthur, Switzerland) were implanted in combination with one type of uncemented stem. Patients were followed up clinically and radiographically. Mean time of follow-up was 17 years (range 15-20). At the time of follow-up, the acetabular component had been revised or was awaiting revision in 30 hips (24%). Two hips were revised for infection and 23 for aseptic loosening. Four polyethylene liners were exchanged because of excessive wear. One hip was awaiting revision. The survival rate for all acetabular revisions including one hip awaiting revision was 75% (95%CI: 65-85%) at 17 years. These results support the view that smooth, threaded acetabular components do not provide satisfactory long-term fixation and should be abandoned. It is important to closely monitor patients with these components as the failure rate remains high in the long-term. [ABSTRACT FROM AUTHOR]

The aim of the study was to determine whether the incidence of radiolucencies can be reduced using pulsed lavage before cementing the tibia in unicompartmental knee arthroplasty (UKA). We prospectively studied a consecutive series of 112 cemented Oxford UKA in 100 patients in two centres. In group A (n = 56) pulsed lavage and in group B (n = 56) conventional syringe lavage was used to clean the cancellous bone. The same standardised cementing technique was applied in all cases. At a minimum follow-up of one year patients were evaluated clinically and screened radiographs were obtained. The cement bone interface under the tibial plateau was divided into four zones and evaluated for the presence of radiolucent lines. All radiographs were evaluated (n = 112), and radiolucencies in all four zones were found in two cases in group A (4%) and in 12 cases in group B (22%) (p = 0.0149). Cement penetration showed a median of 2.6 mm (group A) and 1.5 mm (group B) (p < 0.0001). We recommend the routine use of pulsed lavage in Oxford UKA to reduce the incidence of radiolucency and to improve long-term fixation. [ABSTRACT FROM AUTHOR]

High survival rates have been reported for the uncemented CLS Spotorno stem up to 10 years. To confirm survival at longer followup we report the minimum 15-year (mean, 17 years; range, 15-20 years) for 257 hips using this stem. We retrospectively evaluated the clinical and radiographic results of all 326 patients (354 THAs) operated between 1985 and 1989. The patients had a mean age of 57 years using an uncemented grit-blasted, tapered titanium femoral stem. Eighty-six patients (89 hips) died and eight patients (eight hips) were lost to followup, leaving 240 patients (257 hips) for evaluation. The femoral component was revised in 35 hips: eight for infection, nine for periprosthetic fracture, one for traumatic loosening, and 17 for aseptic loosening. Survival of the stem was 88% at 17 years (95% confidence interval, 84%-92%), and survival with femoral revision for aseptic loosening as an end point was 94% (95% confidence interval, 91%-97%). The median Harris hip score at followup was 80 points. No thigh pain was reported. Small osteolytic lesions (< 1 cm(2)) were found in the proximal Gruen zones (1 or/and 7) in 28 hips (15%). No distal femoral osteolysis was found. The long-term survival with this type of femoral component remains high in the second decade. [ABSTRACT FROM AUTHOR]

Background: Minimal invasive surgery (MIS) has gained growing popularity in total hip arthroplasty (THA) but concerns exist regarding component malpositioning. The aim of the present study was to evaluate femoral and acetabular component positioning in primary cementless THA comparing a lateral to a MIS anterolateral approach., Methods: We evaluated 6 week postoperative radiographs of 52 hips with a minimal invasive anterolateral approach compared to 54 hips with a standard lateral approach. All hips had received the same type of implant for primary cementless unilateral THA and had a healthy hip contralaterally., Results: Hip offset was equally restored comparing both approaches. No influence of the approach was observed with regard to reconstruction of acetabular offset, femoral offset, vertical placement of the center of rotation, stem alignment and leg length discrepancy. However, with the MIS approach, a significantly higher percentage of cups (38.5 %) was malpositioned compared to the standard approach (16.7 %) (p = 0.022)., Conclusions: The MIS anterolateral approach allows for comparable reconstruction of stem position, offset and center of rotation compared to the lateral approach. However, surgeons must be aware of a higher risk of cup malpositioning for inclination and anteversion using the MIS anterolateral approach.

Purpose: Concerns have been raised in relation to metal-on-metal (MoM) articulations with catastrophic soft-tissue reactions due to metal debris. We reviewed how small head MoM articulations perform in primary uncemented total hip arthroplasty (THA) in young patients at a minimum of ten years., Methods: We retrospectively evaluated the clinical and radiographic results of the first 100 consecutive primary cementless THAs using the 28-mm Metasul MoM articulation in 91 patients younger than 50 years of age at the time of surgery., Results: After 13 years, survival for the endpoint revision due to any reason was 90.9 % and 98.9 % for revision due to aseptic implant loosening. The cumulative incidence of MoM related revisions was 1.2 %. Small proximal femoral osteolysis was found in 18 % of hips. No acetabular osteolysis or loosening was detected. Two hips showed signs of femoral neck impingement with severe damage to the neck., Conclusions: Early in the second decade, MoM-associated complications were rare using the 28-mm Metasul articulation, and aseptic loosening was not a major mode of failure in this cohort of young patients., Level of Evidence: Therapeutic Level IV.

Background: Uncemented femoral components in primary total hip arthroplasty (THA) are commonly used today, but few studies have evaluated their survival into the third decade., Questions/purposes: We evaluated (1) survivorship using femoral revision for any reason as the end point; (2) survivorship using femoral revision for aseptic loosening as the end point; and (3) patient-related and surgical risk factors for aseptic stem loosening at a minimum 20-year followup with an uncemented tapered titanium stem., Methods: We reviewed the clinical and radiographic results of 354 THAs in 326 patients performed between January 1985 and December 1989 using an uncemented grit-blasted, tapered titanium femoral stem. Mean age at surgery was 57 years (range, 13-81 years). Kaplan-Meier survivorship analysis was used to estimate long-term survival. Minimum followup evaluation was 20 years (mean, 22 years; range, 20-25 years); at that time, 120 patients (127 hips) had died, and four patients (five hips) were lost to followup. Multivariate survival analysis using a Cox regression model was performed., Results: Survivorship at 22 years with revision of the femoral component for any reason as the end point was 86% (95% confidence interval [CI], 81%-90%). Survivorship for femoral revision for aseptic loosening as the end point was 93% at 22 years (95% CI, 90%-96%). Undersized stems (canal fill index≤80%) and stems in hips with cup revision were at higher risk for aseptic loosening (hazard ratio, 4.2 and 4.3, respectively). There was a high rate of acetabular revision in this series (38%), mostly related to smooth-threaded, cementless sockets., Conclusions: Uncemented femoral fixation was reliable into the third decade. Age, male sex, and diagnosis were not associated with a higher risk of aseptic loosening., Level of Evidence: Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

The objective of the present cross-sectional study was to determine in vivo titanium ion levels following cementless total hip arthroplasty (THA) using a modular stem system with different shapes for femoral canal fit and multiple neck options. A consecutive series of 173 patients (190 hips) who underwent cementless modular neck THA and a ceramic on polyethylene bearing with a median follow-up of 9 (7-13) years was evaluated retrospectively. According to a standardized protocol, titanium ion measurements were performed on 67 patients using high-resolution inductively coupled plasma-mass spectrometry. Ion levels were compared to a control group comprising patients with non-modular titanium implants (n=11) and to individuals without implants (n=23). Modular neck THA did not result in elevated titanium ion levels compared to non-modular THA. Compared to individuals without implants, both modular THA and non-modular THA showed elevated titanium ion levels. Absolute titanium ion levels, however, were comparatively low for both implants. The data suggest that the present modular stem system does not result in elevated systemic titanium ion levels in the medium term when compared to non-modular stems. Further longitudinal studies are needed to evaluate the use of systemic titanium ion levels as an objective diagnostic tool to identify THA failure and to monitor patients following revision surgery., (Copyright © 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

Purpose: The objective of this retrospective cohort study was to assess the long-term outcome of cementless femoral reconstruction in patients with previous intertrochanteric osteotomy (ITO)., Methods: We evaluated the clinical and radiographic results of a consecutive series of 45 patients (48 hips, mean age 50 years) who had undergone conversion hip replacement following ITO with a cementless, grit-blasted, double-tapered femoral component. Clinical outcome was determined using the Harris hip score. Stem survival for different end points was assessed using Kaplan-Meier survivorship analysis., Results: At a mean follow-up of 20 (range, 16-24) years, 11 patients (12 hips) had died, and no patient was lost to follow-up. Six patients (six hips) underwent femoral revision, two for infection, three for aseptic loosening and one for periprosthetic fracture. Mean Harris hip score at final follow-up was 78 points (range, 23-100 points). Stem survival for all revisions was 89% (95%CI, 75-95) at 20 years, and survival for aseptic loosening was 93% (95%CI, 80-98)., Conclusions: The long-term results with this type of cementless femoral component in patients with previous intertrochanteric osteotomy are encouraging and compare well to those achieved in patients with normal femoral anatomy.

Purpose: Whilst excellent long-term results with contemporary uncemented stems have been reported for total hip arthroplasty in young patients, the survival rates for the whole reconstruction are often compromised by high failure rates on the acetabular site due to peri-acetabular osteolysis and accelerated wear., Methods: In patients 60 years old or younger, we retrospectively reviewed the results at a minimum of ten years of 89 consecutive uncemented total hip replacements in 88 patients using the press-fit Fitmore acetabular component in combination with the CLS Spotorno stem and a 28-mm Metasul metal-on-metal articulation or a 28-mm alumina ceramic on conventional polyethylene bearing. The mean age at the time of surgery was 49 years (range, 25-60). The mean clinical and radiological follow-up was 12 years (range, 10-15)., Results: Six patients (six hips) died and two patients (two hips) were lost to follow-up. Five hips were revised: one for deep infection, one for peri-prosthetic femoral fracture, and one for aseptic stem loosening. In two hips an isolated revision of the acetabular liner was performed (one for recurrent dislocation and one for unexplained pain). No revision was performed for accelerated wear, osteolysis or aseptic loosening of the acetabular shell. We could not detect peri-acetabular osteolysis visible on plain radiographs in those hips evaluated radiographically. The Kaplan-Meier survival with revision for any reason as the endpoint was 94% (95% confidence interval, 86-97) at 12 years., Conclusions: The survival rates and the radiological outcomes with this implant combination in this young and active patient group are encouraging when compared to the results reported for other uncemented cups in this age group.

In a prospective clinical study, 59 patients with anteromedial osteoarthritis of the knee (61 knee joints) underwent minimally invasive medial Oxford unicompartmental arthroplasty phase 3. Clinical and radiographic examinations of 56 knees were carried out at five (4-7) years. American Knee Society (AKS) scores improved from mean 45.5 (20-80) points (knee score) and 55 (15-100) points (function score) before surgery to 90 (30-100) points in both scores after surgery. The position of each implant was determined on screened radiographs using an image intensifier. The implant position was analysed according to the Oxford X-ray rating system. We evaluated nine measures, and there was no detectable correlation between implant position and clinical result. However, long-term studies are needed before it is possible to elaborate an evidence-based guideline on positioning.

The aim of this study was to analyse the complication rates of six different shoulder arthroplasty concepts for different diagnoses in the short and midterm. The study included 485 primary shoulder arthroplasties. The mean follow-up of the cohort was 3.5 (1-10) years. Complications were classified into three categories: (1) without reoperation, (2) soft tissue revision and (3) implant revision. In total, 56 complications were recorded (11.6%): 34 (7%) were category 1 complications, 11 (2.3%) were category 2 and 11 (2.3%) were category 3. For the whole cohort the median follow-up was 1.6 years (1-10 years) and the survival rate without any complication was 90.5% (95% CI: 87.9-93.1). Patients rated the result of their surgery in 270 (55.7%) cases as very satisfied, in 148 (30.5%) as satisfied, in 43 (8.9%) as somewhat disappointed and in 24 (4.9%) as disappointed. A relatively low complication rate was found in this study. Long-term observations are necessary to confirm these results.

Osteoarthritis (OA) secondary to dislocation and dysplasia is a common problem in patients with cerebral palsy. The purpose of this study was to evaluate the results of total hip replacement (THR) in ambulatory patients with cerebral palsy. Eighteen total hip arthroplasties were performed in 16 ambulatory patients with cerebral palsy. The patient's mean age at surgery was 42 +/- 8 years (range 32-58 years), and the mean follow-up was 10 +/- 6 years (range 2-18 years). Data were obtained by a standardised telephone interview. There was a significant postoperative reduction in pain on the NAS (narrative analogue scale) from 8.4 preoperatively to 1.1 postoperatively (p = 0.002). At follow-up no stem had been revised. Three cups were revised for aseptic loosening at two and six years, and one cup was revised for recurrent dislocation of the hip. One hip was revised for infection 12 years after the index surgery. One hip dislocated (three months postoperatively) and was treated by closed reduction. In ambulatory patients with cerebral palsy and secondary osteoarthritis of the hip THR can provide long-term pain relief and improved function. The rate of long term complications was moderate in this series; however, the dislocation rate was higher than in standard OA cases.

The purpose of this prospective study was to describe cementless humeral surface replacement arthroplasty (CHSRA) as a bone preserving treatment option for patients with fixed anterior glenohumeral dislocation. Ten patients with post-traumatic fixed anterior glenohumeral dislocation underwent CHSRA with a mean follow-up of 24 months. All patients were evaluated clinically using the Constant score and with radiographs in two planes. There were two reoperations: one patient developed glenoid erosion and was revised and in another case redislocation occurred. Clinical or radiographical signs of implant loosening were not found. The humeral head centred in the glenoid in nine out of ten cases radiographically. The Constant score increased from 20 points preoperatively to 61 points postoperatively (p < 0.007). CHSRA is a viable treatment option for elderly patients with fixed anterior glenohumeral dislocation and bone defects of the humeral head. Good clinical results and a moderate complication rate were found in the short term.

In a cadaver study, we prepared 20 matched pairs of human femora using chipped-tooth broaches and robotic milling with the same geometry. For robotic bone preparation the CASPAR robotic system with a rotating milling head was used. Cancellous bone was irrigated with 1 liter of pulsed lavage and the specimens were embedded in specially-designed pots. After vacuum mixing, bone cement was introduced in a retrograde manner and subjected to a standard pressure protocol with a constant force of 3,000 N. Radiographs were taken and horizontal sections were obtained at predefined levels, using a diamond saw. Microradiographs of the bone slices were taken, digitized and analyzed to assess cement penetration into cancellous bone. No femoral fractures or fissures occurred with either preparation technique. The microradiographic evaluation showed no morphometric differences between chipped-tooth broaches and robotic milling as regards cement penetration into cancellous bone. Therefore, in the presence of pulsed lavage, we conclude that robotic bone preparation does not increase cement penetration into cancellous bone of the proximal end of the femur.

We evaluated the clinical and radiographic results of the first consecutive 154 implantations of a cementless, double-tapered straight femoral stem (cementless Spotorno (CLS), Sulzer Orthopedics) in 141 patients under the age of 55 (mean 47 (13-55)) years. After a mean follow-up of 12 (10-15) years, 11 patients (11 hips) had died and 7 (7 hips) could not be located. 5 patients (5 hips) underwent femoral revision-1 for infection, 1 for periprosthetic fracture and 3 for aseptic loosening of the stem. The overall survival rate of the stem was 97% at 12 years (95% confidence limits, 93%-100%), and survival with femoral revision for aseptic loosening as an end point 98 (95-100)%. The survival rate of the acetabular components was 78 (71-85)% after 12 years. The median Harris hip score at follow-up was 84 points. None of the patients had thigh pain. Radiolucent lines in Gruen regions 1 and 7 were present in 21 hips (17%). 2 hips had radiolucent lines in regions 2-6 on anteroposterior (AP) radiographs. No femoral osteolysis was detected. The mid- to long-term survival with this type of femoral component is excellent and compares favorably with cemented stems in this age group. However, the high rate of cup loosening and the low Harris hip scores are a concern in this subgroup of young patients.

We performed an experimental study to compare the effectiveness of robotic bone milling (Robodoc and CASPAR) with hand-broaching as regards primary rotational stability of 7 different cementless stems. Using 48 synthetic femora and a specially-designed apparatus, we compared the implant stability of proximal and distal rotational stem displacement (slip) in relation to the cortex. We also measured stem deformation (twist) and the location of torque transfer from stem to cortex (i.e., fixation pattern). 5-ROM, Antega, and ABG stems were more stable in hand-broached femora. Osteolock stems showed no difference between CASPAR and hand preparation, but rotational stability was better in the Robodoc group. G2, VerSys ET and Vision 2000 stems gave increased rotational stability in the robotic groups. When placed too laterally, Vision 2000 showed a pattern of more distal fixation. The findings emphasize the current difficulties in creating a perfect match of robotically-milled cavity and stem geometry to achieve enhanced primary rotational stability. The pattern of fixation seems to depend not only on stem design, but also on canal preparation and stem positioning.