Ten-year results of a press-fit, porous-coated acetabular component

We retrospectively reviewed, ten years after surgery, 100 consecutive total hip replacements in which the Duraloc 300 cup had been used. Post-operative radiographs were analysed for placement of the cup and interface gaps and follow-up radiographs for lucent lines, osteolysis, wear and migration. All the components were found to be stable with no evidence of loosening. The mean rate of wear was 0.12 mm/year. Three hips developed acetabular osteolysis at the level of the apex hole. Two have successfully undergone bone grafting without removal of the implants and one patient is awaiting surgery. The Duraloc 300 cup has a survival of 100% at ten years with no aseptic loosening and a low incidence of pelvic osteolysis.     

Experiences with the Plasmacup--early stability, wear, remodelling, and outcome

Whilst advances in cementing technique have led to improvement in the survival of cemented femoral stems in total hip arthroplasty (THA), cup failure due to aseptic loosening remains a major clinical problem. These observations have led to a move away from cemented cup designs, particularly in young patients, towards uncemented implants. The Plasmacup is a hemispherical, press-fit, cementless, titanium-shelled, acetabular component with a polyethylene liner. In this article we review our experience of its pattern of early migration, wear, bone remodelling, and mid-term survival. In 18 cups followed for 2 years in subjects with a mean age at operation of 58 years, the mean total vectorial cup migration was 0.75 mm, and cup orientation remained stable (EBRA method). The mean polyethylene linear wear rate over this period was 0.21 mm/year. In 27 cups followed for 6 months using dual-energy X-ray absorptiometry (DXA), average bone loss was -5%, and the pelvic bone-remodelling pattern was consistent with the rim-loading principle of the cup design. In a clinical review of the outcome of 128 cups in 104 patients with a mean age at operation of 51 years and follow-up of 59 months, we found that 82% of patients had a good or very good Merle D'Aubigne score, and cup survival rate was 98% (Kaplan-Meier). Four cups had small radiographic areas of focal osteolysis and three had been revised (two for recurrent dislocation and one for deep sepsis; none were revised for aseptic loosening). The mean linear wear rate in this series was 0.14 mm/year. In conclusion, the Plasmacup shows satisfactory early stability, a wear rate similar to other uncemented cups, and favourable mid-term clinical function and survival rates.     

Midterm survivorship of a press-fit, plasma-sprayed, tri-spike acetabular component

Press-fit acetabular cups without screw holes can limit migration of particulate wear debris and reduce risk of acetabular osteolysis and device loosening. The Tri-Spike cup (Biomet, Inc, Warsaw, Ind) includes a titanium alloy plasma spray porous surface and does not require screw fixation. We retrospectively examined the incidence of cup loosening and acetabular osteolysis after implantation of 45 cups (44 patients) with mean follow-up of 7.3 years (range, 4-9 years). Only one patient (one cup) had evidence of less than 1 mm of retroacetabular radiolucency at 3 years (nonprogressive), which was found to remain firmly fixed during revision of the aseptically loosened femoral component. No cups were removed or revised at latest follow-up. Projected Kaplan-Meier survivorship at 9 years was 100% for cup loosening/revision and 97.8% for radiolucency.     

Acetabular revision without cement

We reviewed the clinical and radiologic results of 47 cementless acetabular revisions performed by a single surgeon. The mean follow-up period was 58 months. The American Academy of Orthopaedic Surgeons (AAOS) acetabular defect classification was type I in 4 hips, type II in 9 hips, and type III in 32 hips. All patients received AML (Depuy, Warsaw, IN) Duraloc cup implants. Morcellized allograft was used in 23 hips (49%), and screw augmentation in 22 hips (47%). The Harris Hip score improved from 72 to 90 points. No revisions were performed for aseptic loosening. Nonprogressive thin radiolucent lines were found in a single zone in 10 hips (21%) and in all 3 zones in 5 hips (11%). No migration was found in any cups with radiolucent lines, and the presence of a radiolucent line was considered clinically unimportant. Progressive loosening with migration of the cup was found in 1 hip (2%). Kaplan-Meier survivorship using revision for aseptic loosening or radiologic loosening as end points was 92% at 72 months. No statistically significant difference was found in the survival of the cups fixed with or without screws. These encouraging midterm results confirm the role of cementless acetabular revision.     

Migration analysis of cemented Müller polyethylene acetabular cups versus cement-free Zweymüller screw-attached acetabular cups

OBJECTIVE: Is the cementless Zweymüller hip cup superior to the cemented Müller cup? METHOD: This article presents a radiographic analysis of 25 cemented Müller acetabular cups versus 22 cementless Zweymüller cups using the Einbildr?ntgenanalyse (EBRA), a software tool for radiographic measurement of acetabular cup migration. In addition, we determined the effects of the cup anteversion and inclination, the polyethylene wear, the lateral bone coverage of the acetabular cup, the position of the center of rotation, and individual factors on the incidence of cup migration. RESULTS: The incidence of cup migration was 64% in the cementless group and 48% in the cemented group after a mean follow-up of 6 years. The average migration rate was 0.33 mm/a for cementless Zweymüller cups and 0.38 mm/a for cemented Müller cups. Cup anteversion and inclination showed no effect on the incidence of cup migration. The combination metal-polyethylene (0.17 mm per year) demonstrated a significantly higher wear rate in comparison to the ceramic-polyethylene combination (0.11 mm per year). Incompletely lateral covered cups demonstrated a significantly higher incidence of cup migration. Cranial or medial deviations of the center of rotation up to 5 mm are tolerable, in contrast to caudal or lateral deviations that lead to a significantly higher incidence of cup migration. CONCLUSION: The superiority of the cementless Zweymüller cup was not observed. We recommend a complete lateral bone coverage of the hip cup. Cranial and medial deviations of the center of rotation up to 5 mm are tolerable. In the present study the polyethylene wear of the ceramic-polyethylene combination was significantly less as compared with the metal-polyethylene combination.     

Long-term results with cementless Fitek (or Fitmore) cups

Fitek cementless cups have been adopted in our department in 1989. The first 100 consecutive Fitek implants were analyzed clinically (Harris hip score) and radiographically (anteroposterior and lateral x-rays) with a mean follow-up of 9.7 years. We did not have any case of cup loosening or any other problem requiring cup revision. In this series, we had 86 excellent, 10 good, 2 fair, and 2 poor results. The 2 poor results were because of 2 cases of aseptic loosening of the stem (1 cemented and 1 cementless). The x-rays showed an average angle of cup inclination of 36.5 degrees (range 16 degrees -54 degrees ) after surgery and no variations at the last follow-up. Bidimensional linear wear of the acetabular component showed 6 cases of measurable wear with an average wear rate per year of 0.265 mm. The overall wear rate per year was 0.02 mm. At the time of the last follow-up examination, we had 3 femoral osteolysis and no case of acetabular osteolysis. In our series, we observed "lack of contact" zones above the polar depression in 71 cases immediately after surgery. The average thickness of these lines was 1 (range 0.5-3.5) mm. Of these, at the last follow-up, 61 cases (86%) showed a complete "filling" of the "lack of contact," whereas in 10 (24%), the "filling" was incomplete (4 cases still showing a radiolucent line [相似文献   

Wear and periprosthetic osteolysis of modular, hemispheric acetabular cups]

Osteolysis associated with polyethylene wear has become one of the most prevalent complications associated with uncemented modular, hemispherical cups. Sixty-five consecutive total hip arthroplasties (ABG i, Howmedica, Stryker) were followed 6-12 years. Cumulative survivorship for the cup was 55.7% after 10 years. There were 20 cups revisions because of polyethylene wear and periprosthetic osteolysis (14 cups) or cup loosening (6 cups). Stability was assessed intraoperatively, 14 cups were revised, whereas 6 new polyethylene cups were cemented into stable metal-back of acetabular component. The average annual wear of revised cups was 0.32 mm. The annual wear of not revised cups was 0.12 mm. The differences were statistically significant (p = 0.002). The mean area of osteolysis was 472 mm2 (SD 257 mm2). There was no significant correlation between wear and area of osteolysis. There was significant correlation R = 0.54, p = 0.014) between time to revision and area of osteolysis. There were no significant differences of wear of polyethylene inlay or area of osteolysis between stable and unstable acetabular cups.     

Migration of the Duraloc cup at two years

We carried out 71 primary total hip arthroplasties using porous-coated, hemispherical press-fit Duraloc '100 Series' cups in 68 consecutive patients; 61 were combined with the cementless Spotorno stem and ten with the cemented Lubinus SP II stem. Under-reaming of 2 mm achieved a press-fit. Of the 71 hips, 69 (97.1%) were followed up after a mean of 2.4 years. Migration analysis was performed by the Ein Bild Rontgen Analyse method, with an accuracy of 1 mm. The mean total migration after 24 months was 1.13 mm. Using the definition of loosening as a total migration of 1 mm, it follows that 30 out of 63 cups (48%) were loose at 24 months.     

A Comparison of a Second- and a Third-Generation Modular Cup Design : Is New Improved?

The highly cross-linked polyethylene liners currently used with modular uncemented cups have substantially decreased wear and osteolysis at early follow-up. However, retroacetabular osteolysis has still been reported in some cases with DePuy Orthopaedic's (Warsaw, IN) second-generation Duraloc acetabular shell. DePuy's third-generation Pinnacle cup incorporates a different shell-liner locking mechanism. We compared the clinical outcome among a matched series of 42 Duraloc and 42 Pinnacle cups at a mean follow-up of 5.9 years. Although the Harris Hip Scores and wear rates were not statistically different between the 2 cup designs, retroacetabular osteolysis behind the central hole was absent among the Pinnacle cups but noted among 19% of the Duraloc cups.     

Effect of Cementless Acetabular Component Orientation,Position, and Containment in Total Hip Arthroplasty for Congenital Hip Disease

We evaluated the effect of the inclination angle, position, and containment of 53 cementless cups inserted in patients with congenital hip disease (CHD), after a minimum of 10 years of follow-up. The polyethylene wear rate was significantly greater when the cup was placed in more than 45° inclination (P = .045) or if the cup was placed lateral to the teardrop position by more than 25 mm (P = .001). Aseptic loosening of the femoral component was significantly greater when the cup was placed more than 25 mm superiorly to the teardrop (P = .049). Cup placement of more than 25 mm lateral to the teardrop affected significantly periacetabular osteolysis (P = .032). In CHD cases, it is preferable to avoid excessive vertical inclination, lateral, and superior placement of cementless cups in an attempt to obtain better containment.     

Modes of failure of a threaded acetabular cup

A radiographic study of a singular type of threaded cup, revised due to aseptic loosening, was performed with Einzel-Bild-Roentgen-Analyse (EBRA) to detect eventual risk factors and patterns of loosening. Fifty-three cups of 50 patients were revised. Forty-two cups could be measured with EBRA. No cup had obvious osteolysis, 33 cups demonstrated early migration, and all cups had migrated at the time of revision. Twenty-eight of the cups had a change of inclination and 21 of anteversion, respectively. The mean migration was 1.9 mm in the medial and 7.9 mm in the cranial direction; the mean wear rate was 0.2 mm/year. Cups with early migration had a higher migration rate. All male patients had early migration; medially placed cups had less migration than the other cups. Wear was not significantly affected by the migration of the implant. No cup had a complete radiolucent line, and the only radiographic sign for loosening was the change of position of the cup. Medial placement showed less migration in case of loosening. Regular radiographic follow-up is recommended for the examined implant, and the cup should not be used in the future.     

Long-term results of uncemented Parhofer-Mönch screw rings

AIM: The aim of this study was an analysis of the long-term behaviour and implant migration of the Parhofer-M?nch-screw cup seen in patients between 1982 and 1991. METHOD: 92 cups (m : f = 53 : 39, mean age 53 +/- 7 years) were included mainly prospectively. After 118 +/- 45 months all patients were examined clinically and radiologically. Digital migration analysis was performed using the single-film X-ray analysis (Einbildr?ntgenanalyse, EBRA). RESULTS: 5 patients had died. 32 cups were revised, in 7 patients a loosening of the cup was suspected. The 10-year-survival was 71.4 %. In 53 of 81 analysed cups a migration of more than 1 mm was shown, 28 cups did not migrate. In comparison to these stable implants the survival of migrated cups was significantly inferior. CONCLUSION: The 10-year-survival and the high rate of implant migration document the poor results of the PM cup. In spite of an extraordinary primary stability, the failure of secondary osseointegration represents the main cause of loosening in this type of cup.     

Primary Total Hip Arthroplasty With Duraloc Cup in Patients Younger Than 50 Years : A 5- to 7-Year Follow-Up Study

We evaluated the clinical and radiographic results of 67 (64 patients) cementless Duraloc-300 cups for young active patients after a mean follow-up period of 6.2 years. The preoperative mean Harris hip score improved from 46.24 to 96.5 points at 5 years. The survivorship of the cup, using radiographically confirmed aseptic loosening as the end point, was 100% at 5 years. The mean rate of liner wear was 0.125 mm/y (00-0.39 mm/y). Acetabular osteolysis was found in 14% (9 hips) of the 67 hips, and the osteolysis is related to polyethylene wear (P = .0024) and sex (P = .001). Although there was no aseptic loosening of the components, there was a high rate of liner wear of the polyethylene liner and acetabular osteolysis.     

13-Jahres-Ergebnisse der CLS-Spreizpfanne in der primären Hüftendoprothetik

BACKGROUND: Clinical studies of the CLS expansion cup in hybrid hip arthroplasty generally show good results. However, follow-up times are limited to between 5 and 10 years. The aim of our study was to assess the clinical and radiological outcome of the CLS cup after more than 10 years. MATERIAL AND METHOD: After a follow-up of 13 years (10-15 years), 41 of 186 patients with a total of 41 CLS cups were available for clinical and radiological evaluation. In addition, a digital analysis of all radiographs was done. This included measurement of the migration, inclination, polyethylene wear, shaft subsidence, and osteolytic lesions. RESULTS: The average preoperative Harris hip score was 48, which increased to 81 at final follow-up. No acetabular loosening was found. Two cups (5%) showed osteolytic lesions not exceeding 50% of the specific zone according to DeLee and Charnley and were considered stable. There was no migration or inclination of the cups. The average polyethylene wear corresponded to 0.1 mm/year. Sixteen patients (39%) showed osteolyses around the stem and were considered loose. CONCLUSION: The CLS expansion cup provides excellent clinical results after 13 years in hybrid total hip arthroplasty. Time-correlative polyethylene wear and the extremely high rate of stem loosening have no consequences for the cup stability in our patient group. Acetabular osteolysis is rare.     

Ten to twelve-year results with the Zweymüller cementless total hip prosthesis

Between January 1987 and December 1990, 221 Zweymüller cementless total hip arthroplasties were performed in 211 patients with idiopathic osteoarthritis. A total of 136 patients (142 prostheses) were evaluated at a mean follow-up of 134 months (SD 9.5). The study group consisted of 78 Hochgezogen and 64 Stepless stem prostheses, all with a threaded titanium cup and ceramic head. No clinical and radiological differences were found between the 2 stem prostheses. Seven cups had been revised because of aseptic loosening; 17 cups showed radiolucent lines, osteolysis, or migration. Mean linear polyethylene wear of 105 (74%) cups was 0.46 mm (SD 0.27), with an annual wear of 0.04 mm (SD 0.02). Wear did not correlate with pain, cup migration, radiolucent lines, or osteolysis. Cumulative survival was 96%. Zweymüller cementless total hip arthroplasty showed good midterm results.     

Inferior stabilization of cementless compared with cemented dual-mobility cups in elderly osteoarthrosis patients: a randomized controlled radiostereometry study on 60 patients with 2 years’ follow-up

Background and purpose — Elderly patients may benefit from a dislocation low-risk dual-mobility (DM) articulation in total hip arthroplasty, but the best cup fixation method is unknown. We compared cup migration for cemented and cementless DM cups using radiostereometry.Patients and methods — In a patient-blinded randomized trial, 60 patients (33 female) with osteoarthritis were allocated to cemented (n = 30) or cementless (n = 30) Avantage DM cup fixation. Criteria were age above 70 years, and T-score above –4. We investigated cup migration, periprosthetic bone mineral density (BMD), and patient-reported outcome measures (PROMs) until 24 months postoperative follow-up.Results — At 24 months mean proximal cup migration was 0.11 mm (95% CI 0.00–0.23) for cemented cups and 0.09 mm (CI –0.09 to 0.28) for cementless cups. However, cementless cups generally migrated more than cemented cups at 12 and 24 months. Cemented cups had no measurable migration from 3 months’ follow-up, while cementless cups had not yet stabilized at 24 months in all rotations. Cementless cups showed statistically significantly more maximum total point motion (MTPM) at 12- and 24-month follow-up compared with cemented cups in patients with low systemic BMD (p = 0.01). Periprosthetic BMD changes did not statisticially significantly correlate to proximal migration in either cup fixation group (p > 0.05). PROMs improved similarly in both groups.Interpretation — Cemented cups were well fixed at 3 months. The cementless cups migrated more in patients with low BMD, showed an inconsistent pattern of migration, and migrated in different directions during the first and second year without tendency to stabilization. Cemented fixation of the Avantage DM cup seems safer in elderly patients

The most common indication for revision of a conventional primary total hip arthroplasty (THA) is aseptic loosening of the components (SHAR 2016, NJR 2017, DHAR 2018).Implant fixation method (i.e., cemented or cementless) in primary THA seems mainly based on the surgeon’s preference and national trends. The Danish Hip Replacement Registry report shows a decrease in the use of cemented cup fixation in osteoarthrosis (OA) patients above 70 years (DHAR 2018). This trend has also been described in the United Kingdom (UK) and Australian Joint Registries, while in Sweden and Norway cemented cup fixation is still the preferred fixation method in elderly patients (SHAR 2016, NAR 2017, NJR 2017).The dual-mobility (DM) concept, with 2 articulation surfaces and increased jump distance, may decrease the dislocation rate and increase range of motion compared with standard single mobility (SM) THAs. The long-term survival and the best fixation method of the newer Avantage Reload DM cup in elderly patients is currently unknown but retrospective studies on other types of primary DM THAs suggest acceptable survival rates (Batailler et al. 2017) .Excessive early (2-year) implant micromotion measured with radiostereometric analysis (RSA) is a strong predictor for later implant loosening and poor survival (Karrholm et al. 1997, Nieuwenhuijse et al. 2012, Pijls et al. 2012), and our primary aim was to investigate the early RSA-measured migration of cemented and cementless Avantage DM cups in elderly (> 70 years old) OA patients until 24 months’ follow-up. Secondary endpoints included systemic and periprosthetic bone mineral density (BMD) measurements, and clinical outcome scores.     

Cementless acetabular replacement in patients with rheumatoid arthritis: a 6- to 14-year prospective study

Sixty-three consecutive patients who had 82 Harris-Galante porous acetabular cups (HGP1) (Zimmer Inc, Warsaw, IN) implanted for the treatment of rheumatoid arthritis were prospectively assessed since 1986. At last examination, 12 patients (16 hips) had died, and 1 patient (1 hip) was lost to follow-up. A total of 65 hips in 50 patients were available for the latest review. The follow-up period was 6.8 years to 14 years (mean, 9.1 years). There had been 6 revisions: 1 for deep infection and 5 for polyethylene cup wear. Survivorship analysis for all failures estimated that 75% of hips would still be revision-free after 4558 days (12.5 years). Polyethylene wear has been identified in a further 7 cases at last examination. The average linear cup wear per year was 0.05 mm(range, 0.00-0.66 mm). There were no cases of acetabular loosening or acetabular migration. These results demonstrate the excellent durability of fixation of the HGP1 cups in patients with rheumatoid arthritis. However, a 32-mm head should probably not be used with this cup given the high associated incidence of polyethylene wear.     

Fixation of ultrahigh-molecular-weight polyethylene liners to metal-backed acetabular cups

Locking mechanisms and metal-liner interface surfaces of six modular acetabular systems were evaluated to determine their effect on micromotion and backside wear of the polyethylene liner. Rotational and axial motion between the metal shell and polyethylene liner was measured in the Duraloc (DePuy, Warsaw, IN), Harris-Galante (Zimmer, Warsaw, IN), Impact (Biomet, Warsaw, IN), Lip Loc (Biomet). Precision Osteoloc (Howmedica, Rutherford, NJ), and Reflection (Smith & Nephew Orthopaedics, Memphis, TN) designs at the start of each test, and at 1 million, 5 million, and 10 million cycles. At 10 million cycles, the Lip Loc and Reflection cups had significantly lower rim micromotion than the Duraloc and Harris-Galante cups (F < .0010). The Impact, Precision Osteoloc, and Reflection cups had significantly lower rim subsidence than the Harris-Galante cup (F < .0025). The Harris-Galante cup had significantly greater rotational micromotion than the Lip Loc cup (F < .0074), and had significantly greater interface slippage than the Impact and Reflection cups (F < .0070). The Lip Loc produced significantly lower dome micromotion than the Harris-Galante (F < .0300). The Lip Loc and Reflection cups had significantly less backside wear than the Duraloc and Harris-Galante cups (P < .0001), the Impact cup (P < .0243), and the Precision Osteoloc (P < .0027) cup.     

No association between serum metal ions and implant fixation in large-head metal-on-metal total hip arthroplasty

Background — The mechanism of failure of metal-on-metal (MoM) total hip arthroplasty (THA) has been related to a high rate of metal wear debris, which is partly generated from the head-trunnion interface. However, it is not known whether implant fixation is affected by metal wear debris.

Patients and methods — 49 cases of MoM THA in 41 patients (10 women) with a mean age of 52 (28–68) years were followed with stereoradiographs after surgery and at 1, 2, and 5 years to analyze implant migration by radiostereometric analysis (RSA). Patients also participated in a 5- to 7-year follow-up with measurement of serum metal ions, questionnaires (Oxford hip score (OHS) and Harris hip score (HHS)), and measurement of cup and stem positions and systemic bone mineral density.

Results — At 1–2 years, mean total translation (TT) was 0.04 mm (95% CI: –0.07 to 0.14; p = 0.5) for the stems; at 2–5 years, mean TT was 0.13 mm (95% CI: –0.25 to –0.01; p = 0.03), but within the precision limit of the method. For the cups, there was no statistically significant TT or total rotation (TR) at 1–2 and 2–5 years. At 2–5 years, we found 4 cups and 5 stems with TT migrations exceeding the precision limit of the method. There was an association between cup migration and total OHS < 40 (4 patients, 4 hips; p = 0.04), but there were no statistically significant associations between cup or stem migration and T-scores < –1 (n = 10), cup and stem positions, or elevated serum metal ion levels (> 7µg/L (4 patients, 6 hips)).

Interpretation — Most cups and stems were well-fixed at 1–5 years. However, at 2–5 years, 4 cups and 5 stems had TT migrations above the precision limits, but these patients had serum metal ion levels similar to those of patients without measurable migrations, and they were pain-free. Patients with serum metal ion levels > 7 µg/L had migrations similar to those in patients with serum metal ion levels < 7 µg/L. Metal wear debris does not appear to influence the fixation of hip components in large-head MoM articulations at medium-term follow-up.