Introduction. Durable bone fixation of uncemented porous-coated acetabular cups can be observed at a long-term, however, polyethylene (PE) wear and osteolysis may affect survivorship. Accurate wear measurements correlated with clinical data may offer unique research information of clinical interest about this highly debated issue. Objetive. We assessed the clinical and radiological outcome of a single uncemented total hip replacement (THR) after twenty years analysing polyethylene wear and the appearance of osteolysis. Materials and Methods. 82 hips implanted between 1992 and 1995 were prospectively evaluated with a mean follow-up of 20.6 years (range, 18 to 23). A hemispherical porous-coated acetabular cup matched to a proximally hydroxyapatite-coated anatomic stem and a 28 mm standard PE liner, sterilised by gamma irradiation in air, was used in all hips. Radiological position and the possible appearance of loosening and osteolysis were recorded over time. Penetration of the prosthetic head into the liner was measured by the Roentgen Monographic Analysis (ROMAN) Tool at 6 weeks, 6 months, one year and yearly thereafter. Results. Six cups were revised due to wear and four due to late dislocation. All cups were radiographically well-fixed and all stems showed radiographic ingrowth. Six un-revised hips showed osteolysis on the acetabular side and two on the proximal femoral side. Creep at one year was 0.30 (±0.23) mm. Mean total femoral head penetration was 1.23 mm at 10 years, 1.52 mm at 15 years and 1.92 mm at 23 years. Overall mean wear was 0.12 (± 0.1) mm/year and 0.09 (±0.06) mm/year after the creep period. Mean wear was 0.08 (± 0.06) mm/year in hips without osteolysis and 0.14 (±0.03) mm/year in revised hips or with osteolysis (p<0.001). Conclusions. Although continued durable fixation can be observed with a porous-coated cups and a proximally hydroxyapatite-coated anatomic stem, true wear continues to increase at a constant level over time. PE wear remains as the main reason for revision surgery and osteolysis in uncemented THR after twenty years

Introduction. The mid- or long-term results of acetabular revision total hip arthroplasty (THA) in Korea are rare. The purpose of this study is to report the mid-term radiographic results (> 5 years) of acetabular revision THA with porous-coated cementless Trilogy. ®. cup (Zimmer, Warsaw, IN, USA). Materials and Methods. Between 1999 and 2010, 77 patients (79 hips) had underwent acetabular revision THA with Trilogy. ®. cup. Eight patients (8 hips) were excluded due to death before 5-year follow-up, and 22 patients (23 hips) were excluded due to less than 5-year follow-up or follow-up loss. Forty-seven patients (48 hips) were included in our study. The mean age was 57.9 years (range, 36 to 76 years) and the mean follow-up was 9.8 years (range 5.0 to 16.2 years). The causes of revision were aseptic loosening in 40 hips, and septic loosening in 8 hips, respectively. Both acetabular and femoral revisions were performed in 14 hips and isolated acetabular revision was done in 34 hips. Preoperetive acetabular bone defect according to Paprosky classification was; 1 in type I, 6 in IIA, 11 in IIB, 9 in IIC, 15 in IIIA, and 6 in IIIB. Results. Radiolucent lines less than 2mm were found in 2 hips; one in zone I, another in zone I, II, III. Four hips (1 in type IIC, 1 in IIIA and 2 in IIIB) showed cup migration greater than 5 mm accompanying change of position greater than 5 degrees. However, these patients did not complain pain and showed fixation by secondary stabilization. The Kaplan-Meier survivorship with aseptic loosening as the end point at 10 years was 92.6% (95% confidence interval [CI], 82.6 – 100) and at 15 years was 83.8 % (95% CI, 69.1 – 98.6), respectively. Non-recurrent dislocations occurred in 4 hips. There were no other complication such as sciatic nerve palsy, infection and deep vein thrombosis. Conclusion. Mid-term radiographic results (>5 years) of acetabular revision THA with porous-coated cementless Trilogy. ®. cup showed durable longevity. However, other options such as anti-protrusio cage or cup-cage construct should be considered in severe acetabular bone defect

The technique for removal of bone ingrown extensively coated devices involves cutting the stem below the metaphyseal portion of the stem, followed by removal of the proximal stem and trephine removal of the cylindrical distal portion of the stem. This can be done with or without an extended trochanteric osteotomy (ETO). When the proximal portion of the stem is not bone ingrown (extensive proximal osteolysis, or the stem is broken) or the metaphyseal bone is easily accessed (there is no collar) the stem can be cut through a bone window. In all other cases an ETO at the level where the stem becomes a cylinder is required to disrupt the metaphyseal bone prosthesis interface, cut the stem and extract the proximal portion of the stem.

Glassman described the techniques for removal of cementless stems in 1992. Forty-two loose stems were easily removed, 11 fibrous stable implants were removed with thin osteotomes, and 11 bone ingrown, canal filling, extensively coated stems were removed with trephines. In no cases was reconstruction precluded by stem removal. The critical tools required included manufacturer specific removal tools, high speed burs, thin osteotomes, universal extraction device for connection to the neck, and multiple trephines.

More recently, Kancherla reported the use of trephines to remove 36 porous coated stems. Eighty-six percent of cases were bone ingrown after removal, however complications included an extruded trephine causing a femoral fracture and two periprosthetic fractures thought to be secondary to trephine induced osteonecrosis. The authors recommend bypassing the most distally trephined bone by a minimum of 4cm.

Trephines are very helpful for removing distally fixed stems. Multiple trephines need to be irrigated and changed frequently to avoid dull cutting teeth which can lead to bone necrosis.

Aims

Only a small number of studies exist that report the results of EBM-produced porous coated trabecular titanium cups in primary total hip arthroplasty (THA). This study aims to investigate the patient satisfaction level, clinical function and radiographic outcomes of the patients who underwent THA using an EBM-produced porous coated titanium cup.

Introduction

Fixation has been shown to be the primary indicator of an implant's long-term success. Failure to achieve attachment, especially in acetabular and TKR, has been attributed to a lack of initial stability and gaps between the implant and bone. Gaps greater than 150 microns allow fibrous tissue to form. Properly addressing implant design features can help avoid adverse outcomes.

ASTM International Standards (F1854-09) do not assess the relationship between porosity of the coating and that of cancellous bone, which can lead to an absence of mechanical interlock. This study developed a virtual program that uses human cancellous bone to predict potential skeletal attachment for implants properly placed for TJR. The goal of the Virtual Paradigm was to assess initial contact surface area at the time of implantation.

The use of cementless acetabular components is currently the gold standard for treatment in total hip arthroplasty (THA). Porous coated cups have a low modulus of elasticity that enhances press-fit and a surface that promotes osseointegration. Monoblock acetabular cups represent a subtype of uncemented cup with the liner moulded into the metal shell, minimizing potential backside wear and eliminating the chance of mal-seating. The aim of this study was to compare the short-term clinical and radiographic performances of a modular cup with that of a monoblock cup, with particular interest in the advent of lucent lines and their correlation with clinical outcomes. In this multi-surgeon, prospective, randomized, controlled trial, 86 patients undergoing unilateral THA were recruited. Participants were randomized to either a porous-coated, modular metal-on-polyethylene (MoP) acetabular component (n=46) or a hydroxyapatite (HA)- and titanium-coated monoblock shell with ceramic-on-ceramic (CoC) bearing (n=42). The porous-coated cup had an average pore size of 250 microns with an average volume porosity of 45%, whereas the monoblock shell had an average pore size of 300 microns with an average volume porosity of 48% and a HA coating thickness of 80 nm. There were no baseline demographic differences between both groups regarding sex, age, body mass index (BMI), or American Society of Anaesthesia (ASA) class (p>0.05). All of the sockets were under-reamed by 1 mm. Radiographs and patient-reported outcome measures (PROMs), including modified Harris Hip Score (mHHS), Western Ontario and McMaster Universities Arthritis Index (WOMAC) and University of California at Los Angeles (UCLA) Hip Score, were available for evaluation at a minimum of 2 years of follow-up. A radiolucent distance between the cup and acetabulum of ≥0.5 mm was defined as gap if it was diagnosed from outset or as radiolucency if it had sclerotic edges and was found on progressive x-ray analyses. Thirty-two gaps (69%) were found in the modular cup group and 28 (6%) in the monoblock one (p=0.001). Of the former, 17 filled the gaps whereas 15 turned into a radiolucency at final assessment. Of the latter, only 1 of the gaps turned into a radiolucency at final follow-up (p 0.05) in both groups. Only the porous-coated cup was an independent predictor of lucent lines (OR:0.052, p=0.007). No case underwent revision surgery due to acetabular loosening during the study period. Only 2 cases of squeaking were reported in the CoC monoblock shell. Both porous-coated modular and hydroxyapatite-coated monoblock cups showed successful clinical results at short-term follow-up, however, the former evidenced a significantly higher rate of radiolucent line occurrence, without any association with PROMs. Since these lines indicate the possibility of future cup loosening, longer follow-up and assessment are necessary

Background. Well-fixed cementless stems are sometimes needed to be extracted in patients with complications including periprosthetic infection, stem-neck breakage or trunnionosis. The purpose of this study was to report the clinical outcome in patients undergoing re-implantation surgery following removal of a well-fixed porous-coated cementless stem by the femoral longitudinal split (FLS) procedure(Fig.1, Fig.2). Methods. We conducted a retrospective study and radiographic review of 16 patients who had undergone re-implantation following the FLS procedure to remove a well-fixed stem due to periprosthetic infection, stem-neck breakage or trunnionosis. The study group consisted of 2 men and 14women with an average age of 68.4 years. Mean follow-up was 33.1± 25.0 months. Operation time, intraoperative bleeding, complications, causes of re-operation and clinical score were evaluated and the Kaplan-Meier method was used to evaluate the longevity of the stem. Results. The average operation time was 272±63 minutes and intraoperative bleeding was 420±170 ml. Although postoperative dislocation occurred in 5 hips and sinking of the stem was found in 3 hips after surgery, no progression of the stem sinking was observed and the clinical JOA and JHEQ scores were both improved after re-implantation surgery. Re-implantation surgery with Zweymüller-type stems, which are shorter than those removed, revealed evidence of osseointegration of the stem without femoral fracture. Kaplan-Meier survival analysis of stem revision for any reason as the end point revealed 70.3% survival at 9 years (Fig.3). Conclusion. The FLS procedure is expected to confer successful clinical results without loosening of the stem, following safe extraction of well-fixed porous-coated cementless stems without fracture and will allow re-implantation with shorter cementless stems than those removed. For any figures or tables, please contact the authors directly

The first porous-coated femoral component approved for use without cement was released in 1983. Today, there are many implants with a similar amount of porous coating. The hallmark of these porous-coated implants is a cylindrical shape distally and a triangular metaphyseal shape. Extensively coated components gain initial stability in the femoral diaphysis. Since 1982, we have used extensively porous-coated femoral components in all our patients. Our oldest series of patients is a consecutive non-selected group of 211 hips that have been followed for a mean of 20 years. Combining the loose and the revised, there is only a 3% femoral failure. In addition, we have studied patients with disease processes not originally thought to work well with cementless techniques, including rheumatoid arthritis, avascular necrosis and patients over 65. Despite the good results, the main concern is that proximal bone loss secondary to the stress shielding caused by a stiff extensively porous-coated femoral component will lead to difficulty at the time of revision. At a mean 14 years, we have not seen any adverse clinical consequences that can be attributed to proximal stress shielding, though the longer term consequences of adaptive femoral remodeling need to be followed. In our patients, extensive proximal bone loss secondary to stress shielding is a radiographic sign of bone ingrowth that occurs in 25% of cases. In the remaining 70–75% of cases, lesser degrees of proximal bone loss occur which confirm bone ingrowth. Extensively coated components gain stability in the femoral diaphysis. The femoral diaphysis is prepared with straight reamers until the reamer engages the cortex for 5cm. A slightly larger straight femoral component is inserted with a scratch fit. No matter what the shape of the femur or how osteoporotic the patient, there will always be 4–5cm of cortical bone for fixation of a straight 6 inch stem

The aim of this study was to assess the long-term results of the Kudo type-5 total elbow prosthesis and compare the results of two types of cemented ulnar components. The Kudo type-5 unlinked total elbow prosthesis (Biomet UK Ltd, Bridgend Wales) was developed in 1993. The stem of humeral component is porous-coated with a plasma spray of titanium alloy for cementless use. The ulnar component may be metal-backed with a porous-coated stem or polyethylene alone; the latter designed mainly for cement use. A metal-backed type without a porous-coated stem designed for cement use also came into being after 2003. Between 1993 and 2010, the Kudo type-5 total elbow arthroplasty was performed on 364 elbows in 274 consecutive patients with rheumatoid arthritis. The mean age of the patients at the time of the operation was 60.7 (27–86) years. Twenty elbows had Larsen grade III, 224 had grade IV, and 120 had grade V changes pre-operatively. Before the operation, 346 elbows had severe or moderate pain, 95 had gross valgus-varus instability. Clinical symptoms and revision rates were assessed 4 to 20 years (mean, 9 years) postoperatively. The mean Mayo elbow performance scores were all poor except for three initially (mean overall score, 39.5 points). The overall score had improved substantially both at the early follow-up (1 to 3 years after the operation) and the latest follow-up (4 to 20 years after the operation), with 89.5 and 84.7 points, respectively. At the latest follow-up the overall result was excellent for 185 elbows, good for 103, fair for 11 and poor for 30, with almost complete relief from pain for 298. The arc of movement had increased from a mean of 85.7 °pre-operatively to 95.1 ° post-operatively, and to 98.1 °at the latest follow-up. Spot welds around the humeral stem suggesting solid osseous integration were often seen in the elbows with cementless fixation of the porous humeral stem. At the latest follow-up, implants were removed due to infection in 3 elbows. Twenty-five elbows required ulnar component revision due to loosening of the all-polyethylene component. Two elbows required ulnar component revision due to loosening of the metal-backed component. Seven elbows required humeral component revision due to loosening of the humeral components. One elbow required revision due to dislocation. A survival analysis with revision or removal of one or both components as the end point was performed according to the Kaplan and Meier method. The overall survival rate of the prosthesis was 75.2% at 19 years. The survival of 87.0% in the metal-backed group was higher than the 74.3% in the all-polyethylene group. Loosening of the all-polyethylene ulnar component was the main reason for deterioration in the long-term outcome. We conclude that the long-term results of the Kudo type-5 total elbow arthroplasty is acceptable and cemented fixation of metal-backed ulnar component had better long-term survival than the all-polyethylene component

Stems are a crucial part of implant stabilization in revision total knee arthroplasty. In most cases the metaphyseal bone is deficient, and stabilization in the diaphyseal cortical bone is necessary to keep the implant tightly fixed to bone and to prevent tilt and micromotion. While sleeves and cones can be effective in revision total joint arthroplasty, they are technically difficult and may lead to major bone loss in cases of loosening or infection, especially if the stem is cemented past the cone. A much more conservative method is to ream the diaphysis to the least depth possible to achieve tight circumferential fixation, and to apply porous augments to the undersurface of the tibial tray or inner surface of the femoral component to allow them to bottom out against the bone surface and apply compressive load. If a robust, strong taper, stem and component combination is used, rim contact on only one side is necessary to achieve rigid permanent fixation. Porous and non-porous stems are available. The non-porous stems should have a spline surface that engages the diaphyseal bone and achieves rigid initial fixation but does not provide long-term axillary support. In that way the porous rim-engaging surface can bear compressive load and finally unload the stem and taper junction. Correctly designed stems do not stress relieve unless they are porous-coated. In situations where metaphyseal bone is not available, porous-coated stems that link to hinge prostheses are a very important part of the armamentarium in complex revision arthroplasty. Use of stems requires experience and special technique. Slight underreaming and initial scratch fit are necessary techniques. This does not result in tight fixation every time because split of the cortex does occasionally occur. In most cases these splits do not need to be repaired, but when there is a question, an intra-operative x ray should be taken and the surgeon should be prepared to repair the fracture. Stems are an essential part of revision total knee arthroplasty. A tightly fit stem in the diaphysis is necessary for fixation when metaphyseal bone is deficient. No amount of cement pressed into the deficient metaphyseal bone will substitute for rigid stem fixation

Introduction. Patients with osteonecrosis of the femoral head are typically younger, more active, and often require high rates of revision following primary total hip arthroplasty. However, outcomes of revision hip arthroplasty in this patient population have been rarely reported in the literature. The purpose of this study was to report the intermediate-term clinical and radiographic outcomes of revision hip arthroplasty in patients with osteonecrosis of the femoral head. Materials & Methods. Between November 1994 and December 2009, 187 revision hip arthoplasty were performed in 137 patients who had a diagnosis of osteonecrosis of the femoral head. Exclusion criteria included infection, recurrent instability, isolated polyethylene liner exchange, and inadequate follow-up (less than 3 years). The final study cohort of this retrospective review consisted of 72 patients (75 hips) with a mean age of 53.3 years (range, 34 to 76). Components used for the acetabular revision included a cementless porous-coated cup in 58 hips and an acetabular cage in 2 hips. Components used for the femoral revision included a fully grit-blasted tapered stem in 30 hips and a proximally porous-coated modular stem in 9 hips. The mean duration of follow-up was 7 years (range, 3 to 17). Results. Mean Harris hip score improved 49 points preoperatively to 90 points. At the time of final follow-up, 11 hips (14.7%) patients required additional reoperation procedure. Of these, six for aseptic loosening of acetabular cup and/or femoral stem, two for deep infection, one for recurrent dislocation, one for periprosthetic femoral fracture, and one for ceramic head fracture. Kaplan-Meier survivorship with an end point for cup revision for aseptic loosening was 98.4% at 5 years, 93.4% at 10 years, and with an end point for stem revision for aseptic loosening was 100% at 5 years, 97.4% at 10 years (Fig. 1). Conclusions. Unlike the previous report, our study showed lower failure rate of femoral stem after revision hip arthroplasty using modern cementless femoral components in patients with osteonecrosis of the femoral head. Aseptic cup loosening or osteolysis is the most common mechanism of failure at the medium-term follow-up following revision hip arthroplasty in these patients group

In properly chosen patients, cementless total knee arthroplasty has achieved success rates equal to cemented designs. The initial variable results of early cementless total knee replacements were a function of design, surgical technique and patient selection. Important design considerations that have enhanced biologic ingrowth include the use of commercially pure titanium with optimal pore size and porosity, and avoidance of porous-coated stems and plugs that cause stress shielding of the bone-implant interface. Factors in surgical technique that enhance bone ingrowth include precise bone cuts that maximise bone-implant contact, and the application of autogenous bone slurry to cut surfaces. Additional factors are restoration of normal alignment, appropriate ligament balance, and the reproduction of the patient's native tibial slope in order to prevent tibial component subsidence. Young and active patients are ideal biological hosts for the use of cementless knee fixation. Their relatively dense cancellous bone and rich blood supply provides for robust purchase for initial fixation and the appropriate milieu for long-term biologic fixation. With increasing life expectancy, this more durable interface is desirable. With avoidance of porous-coated stems and pegs and prevention of fibrous tissue attachment, potential future revisions are more bone-sparing relative to methylmethacrylate fixation. Numerous reports, as well as the authors’ published 10- to 14-year results, demonstrate that cementless fixation in appropriately selected patients provides results comparable to cemented TKA, with the advantage of conserving bone stock and eliminating the potential problems of cement fixation

The purpose of this investigation is to assess the rate of wear the effect once the “bedding in period”/ poly creep had been eliminated. Creep is the visco-elastic deformation that polyethylene exhibits in the first 6–12 weeks. We also assessed the wear pattern of four different bearing couples in total hip arthroplasty (THA): cobalt-chrome (CoCr) versus oxidized zirconium (OxZir) femoral heads with ultra-high molecular weight polyethylene (UHMWPE) versus highly-crosslinked polyethylene (XLPE) acetabular liners. This was a randomized control study involving 92 patients undergoing THA. They were randomized to one of four bearing couples: (1) CoCr/UHMWPE (n= 23), (2) OxZir/UHMWPE (n=21), (3) CoCr/XLPE (n=24), (4) OxZir/XLPE (n=24). Patients underwent a posterior approach from one of three surgeons involved in the study. All patients received a porous-coated cementless acetabular shell and a cylindrical proximally coated stem with 28 mm femoral heads. Each patient was reviewed clinically and radiographically at six weeks, three and 12 months, two, five and 10 years after surgery. Standardized anteroposterior and lateral radiographs were taken. All polyethylene wear was measured by an independent blinded reviewer. Linear and volumetric wear rates were measured on radiographs using a validated computer software (Polyware Rev. 5). Creep was defined as the wear at 6 or 12 weeks, depending on if there was a more than 10% difference between both measurements. If a greater than 10% difference occurred than the later period's wear would be defined as creep. 72 hips were included in analysis after exclusion of seven revisions, three deaths and 10 losses to follow-up. The annual linear wear rates (in mm/y) at 10 years were (1) 0.249, (2) 0.250, (3) 0.074 and (4) 0.050. After adjusting for creep these rates become were (1) 0.181, (2) 0.142, (3) 0.040 and (4) 0.023. There is statistical differences between raw and adjusted linear wear rates for all bearing couples. The percentage of the radiographically measured wear at 10 years due to creep is (1) 30% (2) 44%, (3) 58.5% and (4) 51.5% with significant differences in couples with XLPE versus those with UHMWPE. There was no significant correlation between age, gender, cup size, tilt, planar anteversion and the linear or volumetric wear rates. The linear wear rate of both UHMWPE and XLPE are even lower thxdsxzan previously described when creep is factored out. XLPE has again demonstrated far superior linear wear rates at 10 years than UHMWPE. There were no significant differences in wear rate at 10 years between CoCr and OxZir, this may be due to an underpowered study. XLPE exhibits proportionally more creep than UHMWPE within the first 6–12 weeks and accounts for more of the total wear at 10 years as measured radiographically at the end period

Since 1982, we have used extensively porous-coated femoral components. Our oldest series of patients is a consecutive non-selected group of 211 hips that have been followed for a mean of 20 years. Combining the loose and the revised, there is a 3% femoral failure. Currently we are following 8,020 hips with a mean follow up of 7 years (0–29 years). Twenty-six percent of the patients have a follow up visit more than 10 years after surgery. The mean age of at the time of surgery was 62 years old (15–97 years). One percent of hips have been revised most commonly for failure of ingrowth-49, infection-19, and stem fracture-7. We have studied patients with disease processes not originally thought to work well with noncemented techniques, including rheumatoid arthritis, avascular necrosis and patients over 65. In 422 hips with more than 20 year follow up, 96% remain satisfied, with less pain, and increased function. Ten years after surgery 57% can walk more than 60 min. or unlimited distances. Using survivorship analysis 96% of patients continue to live independently or with their family 10 years after surgery. For those patients not retired at the time of surgery, 58% continue to work 10 years after surgery. Despite the good results, the main concern is that proximal bone loss secondary to the stress shielding caused by a stiff extensively porous-coated femoral component will lead to difficulty at the time of revision. At a mean 14 years, we have not seen any adverse clinical consequences that can be attributed to proximal stress shielding. Extensive proximal bone loss secondary to stress shielding occurs in 25% of cases. In the remaining 70–75% of cases, lesser degrees of proximal bone loss occur which confirm bone ingrowth

In properly chosen patients, cementless total knee arthroplasty has achieved success rates equal to cemented designs. The initial variable results of early cementless total knee replacements were a function of design, surgical technique and patient selection. Important design considerations that have enhanced biologic ingrowth include the use of commercially pure titanium with optimal pore size and porosity, and avoidance of porous-coated stems and plugs that cause stress shielding of the bone-implant interface. Factors in surgical technique that enhance bone ingrowth include precise bone cuts that maximize bone-implant contact, and the application of autogenous bone slurry to cut surfaces. Additional factors are restoration of normal alignment, appropriate ligament balance, and the reproduction of the patient's native tibial slope in order to prevent tibial component subsidence. Young and active patients are ideal biological hosts for the use of cementless knee fixation. Their relatively dense cancellous bone and rich blood supply provides for robust purchase for initial fixation and the appropriate milieu for long-term biologic fixation. With increasing life expectancy, this more durable interface is desirable. With avoidance of porous-coated stems and pegs and prevention of fibrous tissue attachment, potential future revisions are more bone-sparing relative to methylmethacrylate fixation. Numerous reports, as well as the authors' published 10- to 14-year results, demonstrate that cementless fixation in appropriately selected patients provides results comparable to cemented TKA, with the advantage of conserving bone stock and eliminating the potential problems of cement fixation

Introduction:. Non-cemented, porous-coated metaphyseal sleeves have been designed to improve biologic fixation and stability in revision total knee arthroplasty (TKA) with major bone defects. The aim of this study was to evaluate the clinical results and osteointegration of these sleeves in major bone loss. Materials and Methods:. Between 2008 and 2011, 24 revision TKAs with major bone loss were reconstructed with non-cemented, porous-coated proximal sleeve (DePuy, Warsaw, IN). All patients were prospectively followed for a minimum of 2 years. Indications for use of sleeves were major metaphyseal tibial and femoral bone loss, younger age, and higher activity level. Osteointegration around the sleeves were classified as: . –. Grade 1: Complete osteointegration in all views without any demarcation. –. Grade 2: Sleeves that are not completely osteointegrated but they are stable. Grade 2A: Demarcation less than 2 mm on any view. Grade 2B: Demarcation more than 2 mm on any view . –. Grade 3: Sleeves that are not osteointegrated and unstable with evidence of subsidence. Grade 3A: Subsidence less than 2 mm on any view. Grade 3B: Subsidence more than 2 mm on any view. Results:. Mean range of motion and Knee Society Scores were 108 degrees and 92 respectively. 14 cases were revised for aseptic loosening and 10 cases for infection (which were treated with two stage revision arthroplasty). There was no malalignment, subsidence or re-revision at final follow-up. All sleeves were osteointegrated with majority grade 1 or 2a. Discussion and conclusion:. Short-term results of non-cemented metaphyseal sleeves in major bone loss for loosening of infection demonstrated excellent clinical results and osteointegration

Traditional procedures for orthopedic total joint replacements have relied upon bone cement to achieve long-term implant fixation. This remains the gold standard in number of procedures including TKR and PKR. In many cases however, implants fixed with cement have proven susceptible to aseptic loosening and 3. rd. body wear concerns. These issues have led to a shift away from cement fixation and towards devices that rely on the natural osteoconductive properties of bone and the ability of porous-coated implants to initiate on-growth and in-growth at the bone interface, leading to more reliable fixation. To facilitate long-term fixation through osseointegration, several mechanical means have been utilized as supplemental mechanism to aid in stabilizing the prostheses. These methods have included integrated keels and bone screws. The intent of these components is to limit implant movement and provide a stable environment for bone ingrowth to occur. Both methods have demonstrated limitations on safety and performance including bone fracture due keel induced stresses, loosening due to inconsistent pressfit of the keel, screw-thread stripping in cancellous bone, head-stripping, screw fracture, screw loosening, and screw pullout. An alternative method of fixation utilizing blade-based anchoring has been developed to overcome these limitations. The bladed-based fixation concept consists of a titanium alloy anchor with a “T-shaped” cross-section and sharped-leading end that can be impacted directly into bone. The profile is configured to have a bladed region on the horizontal crossbar of the “T” for engagement into bone and a solid rail at the other end to mates with a conforming slot on the primary body of the prosthesis. A biased chisel tip is added to the surface of the leading blade edge to draw the bone between the anchor's horizontal surface and surface of the implant, thus generating a compressive force at the bone-to-prothesis interface. The anchoring mechanism has been successfully been integrated into the tibial tray component of a partial knee replacement; an implant component that has a clinical history of revision due to loosening. A detailed investigation into the pulloff strength, wear debris generation, compressive-force properties, and susceptibility to tibial bone fracture was carried out on the anchor technology when integrated in a standard tibial tray of a partial knee replacement. When tested in rigid polyurethane bone foam (Sawbones, Grade 15) the pulloff strength of the construct increased by 360% when utilizing the anchor. The tibial tray and anchor construct were cycled under compressive loading and demonstrated no evidence of interface corrosion or wear debris generation after 1 million cycles. In addition, the anchor mechanism was shown to generate 340N of compressive force at the tibial tray-to-bone interface when evaluated with pressure sensitive film (Fuji Prescale, Medium Grade). Finally, the ultimate compressive load to induce tibial fracture was shown to increase by 17% for the anchored tray as compared to a traditional keeled tray when tested in an anatomic tibial sawbones model; and by 19% when evaluated in human cadaveric tibias. For any figures or tables, please contact authors directly

Hypothesis. The Synergy femoral component was introduced in 1996 as a second generation titanium proximally porous-coated tapered stem with dual offsets to help better restore femoral offset at THR. The purpose of this prospective study was to evaluate the long-term (minimum 10 year) clinical and radiographic results and survivorship of this femoral component at our institution. Methods & Analysis. From 1996 to 1999, 256 cementless Synergy femoral components were inserted and followed prospectively in 254 patients requiring THR. 185 were standard offset stems (72.3%) while 71 stems (27.7%) were high offset. The average follow-up was 11.2 years (range 10.0 to 12.9 years). Average age at index THR was 58.9 year. Two hundred and eight stems had standard porous coating while 48 had additional HA coating. Fifty-two cases were either lost to follow-up or had died prior to 10 years follow-up. Patients were followed prospectively using validated clinical outcome scores and radiographs. Kaplan-Meier survival analysis was performed. Results. All health-related outcomes were significantly improved from pre-operative with a mean Harris Hip score and WOMAC at last follow-up of 91.6 and 81.8, respectively. From the initial 256 femoral stems inserted, only 5 stems have been revised. Two stems have been revised for infection. Only one stem has been revised due to subsidence at nine months, likely as a result of a calcar fracture at the index THR. Two stems were revised for peri-prosthetic fracture as a result of patient falls. Radiographic review of remaining stems in situ identified no cases of loosening. Kaplan-Meier survivorship analysis of the femoral component, with revision for aseptic loosening, was 99.2% at 12 years. Conclusion. The Synergy femoral component, a second generation titanium proximally porous-coated tapered stem design with dual offsets, has demonstrated excellent clinical and radiographic results and long-term survivorship (99% at 10 years) at our institution

Background. Aseptic loosening is rare with most cementless tapered stems in primary total hip arthroplasty (THA), however different factors can modify results. We ask if the shape and technique of three current different femoral components affects the clinical and radiological outcome after a minimum follow-up of ten years. Methods. 889 cementless tapered stems implanted from 1999 to 2007 were prospectively followed. Group 1 (273 hips) shared a conical shape and a porous-coated surface, group 2 (286 hips) a conical splined shape and group 3 (330 hips) a rectangular stem. Clinical outcome and anteroposterior and sagittal radiographic analysis were compared. Femoral type, stem position, femoral canal filling at three levels and the possible appearance of loosening and bone remodelling changes were assessed. Results. No thigh pain was reported in unrevised patients. Mean Harris Hip score was lower for patients in group 3 for pain and function at 6 months, two years and at latest follow-up. The survival rate of not having revision of the stem for any cause was 98.5% (95% CI 98.8–100) for group 1 at 12 years, 99.3 % ((95% Confidence Intervals (CI) 97.9–100) for group 2 at 16 years and 97.7% (95% (CI) 94–100) for group 3 at 14 years, and (log rank= 0.109). Thirteen stems from the latter were revised for aseptic loosening. No revision for aseptic loosening was found in the other designs. After controlling all confounding factors, the risk for aseptic loosening in group 3 was related to a lower femoral canal filling (p=0.039, Hazard Ratio (HR):0.918, 95% Confidence Interval (CI):0.846–0.996) and a stem position outside neutral limits in the sagittal alignment (p=0.048, HR:3.581, 95% CI:1.010–12.696). Conclusions. Conical tapered cementless stems are more reliable than rectangular straight designs in primary THA after ten years

Porous-coated acetabular hemispherical components have proven successful in all but the most severe revision acetabular defects. A revision jumbo porous coated component has been defined as a cup with minimum diameter of 66mm in men and 62mm in women. In published studies this size cup is used in 14–39% of acetabular revisions. The advantages of this technique are ease of use, most deficiencies can be treated without structural graft, host bone contact with the porous surface is maximised, and the hip center is generally normal. Jumbo cups are typically used in Paprosky Type 2, 3A, and many 3B defects. Requirements for success include circumferential acetabular exposure, an intact posterior column, and much of the posterior wall. The cup should be stable with a press-fit between the ischium and anterior superior acetabulum with the addition of some superior lateral support. Additional support is provided with multiple dome or rim screws. Survivorship of the metal shell with revision for any reason has been reported to be 80%-96% at time frames from 15–20 years. The most common post-operative complication is dislocation