RESUMEN
PURPOSE: This clinical fluoroscopy study investigated knee kinematics of two different cemented fixed-bearing, posterior-stabilised (PS) total knee arthroplasty (TKA) designs: an asymmetric tibial component including an asymmetric insert designed to optimise personalised balance and fit and its precursor symmetrical design with symmetric insert. METHODS: A consecutive series of patients (16 TKAs from each treatment group) participating in a randomised controlled trial comparing TKA migration was included. The exclusion criterion was the use of walking aids. Flat-panel fluoroscopic recordings of step-up and lunge motions were acquired 1-year postoperatively. Medial and lateral contact points (CPs) were determined to calculate CP displacement, femoral axial rotation and pivot position. Using linear mixed-effects modelling techniques, kinematics between TKA designs were compared. RESULTS: During knee extension between 20° flexion and full extension, the CPs moved anteriorly combined with a small internal femoral rotation (a screw-home mechanism). Whereas CP movement was reversed: femoral rollback, external femoral rotation while flexing the knee between full extension and 20° knee flexion, At larger flexion angles, femoral axial rotation (FAR) occurred around a lateral pivot point both during step-up and lunge. The symmetric design had a 2.3° larger range of FAR compared to the asymmetric design during lunge (p = 0.02). All other kinematics were comparable. CONCLUSION: Despite the differences in design, this study showed that the asymmetric and symmetric PS TKA designs had mostly comparable knee kinematics during step-up and lunge motions. It is therefore expected that the functionality of the successor TKA design is similar to that of its precursor design. LEVEL OF EVIDENCE: Level II, prospective comparative study.
Asunto(s)
Artroplastia de Reemplazo de Rodilla , Prótesis de la Rodilla , Diseño de Prótesis , Rango del Movimiento Articular , Tibia , Humanos , Artroplastia de Reemplazo de Rodilla/métodos , Artroplastia de Reemplazo de Rodilla/instrumentación , Fluoroscopía , Fenómenos Biomecánicos , Femenino , Masculino , Anciano , Tibia/cirugía , Persona de Mediana Edad , Articulación de la Rodilla/cirugía , Articulación de la Rodilla/fisiopatología , Rotación , Osteoartritis de la Rodilla/cirugía , Osteoartritis de la Rodilla/fisiopatologíaRESUMEN
BACKGROUND AND PURPOSE: Different marker-selection methods are applied to represent implant and tibial segments in radiostereometric analysis (RSA) studies of total knee arthroplasty (TKA). Either a consistent set of markers throughout subsequent RSA examinations ("consistent-marker method") is used or all available markers at each follow-up ("all-marker method"). The aim of this secondary analysis was to compare marker-selection methods on individual and group level TKA migration results. METHODS: Data from a randomized RSA study with 72 patients was included. Tibial baseplate migration was evaluated at 3 months, 1, 2, and 5 years postoperatively with both marker-selection methods. Additionally, migration was calculated using 5 fictive points, either plotted based on the consistent set of markers or all available markers. RESULTS: Migration could be calculated with both marker-selection methods for 248 examinations. The same prosthesis and bone markers (n = 136), different prosthesis markers (n = 71), different bone markers (n = 21), or different prosthesis and bone markers (n = 20) were used. The mean difference in maximum total point motion (MTPM) between all examinations was 0.02 mm, 95% confidence interval -0.26 to 0.31 mm. 5 implants were classified as continuously migrating with the consistent-marker method versus 6 implants (same 5 plus one additional implant) with the all-marker method. Using fictive points, fewer implants were classified as continuously migrating in both marker-selection methods. Differences between TKA groups in mean MTPM were comparable with both marker-selection methods, also when fictive points were used. CONCLUSION: Estimated group differences in mean MTPM were similar between marker-selection methods, but individual migration results differed. The latter has implications when classifying implants for estimated risk of future loosening.
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Artroplastia de Reemplazo de Rodilla , Prótesis de la Rodilla , Osteoartritis de la Rodilla , Humanos , Artroplastia de Reemplazo de Rodilla/efectos adversos , Artroplastia de Reemplazo de Rodilla/métodos , Estudios de Seguimiento , Análisis Radioestereométrico , Falla de Prótesis , Diseño de Prótesis , Osteoartritis de la Rodilla/cirugíaRESUMEN
Opening remarks: These guidelines are the result of discussions within a diverse group of RSA researchers. They were approved in December 2023 by the board and selected members of the International Radiostereometry Society to update the guidelines by Valstar et al. [1]. By adhering to these guidelines, RSA studies will become more transparent and consistent in execution, presentation, reporting, and interpretation. Both authors and reviewers of scientific papers using RSA may use these guidelines, summarized in the Checklist, as a reference. Deviations from these guidelines should have the underlying rationale stated.
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Análisis Radioestereométrico , Tomografía Computarizada por Rayos X , Humanos , Falla de Prótesis , Guías de Práctica Clínica como AsuntoRESUMEN
Radiostereometric analysis can be used for computing movement of a tibial baseplate relative to the tibia (termed migration) to determine stability of fixation. Quantifying migration in six degrees of freedom requires establishing a coordinate system in which to express the movement. Establishing consistent migration directions among patients and baseplate designs remains challenging. Deviations in imaging alignment (tibia/baseplate alignment during image acquisition) and surgical alignment (baseplate alignment on tibia) will affect computed migrations when using the conventional globally-aligned baseplate coordinate system (BCS) (defined by calibration box). Computing migration using a local BCS (defined by baseplate) may be preferrable. This paper (1) summarizes the migration equations when using a globally-aligned versus local BCS, (2) proposes a method for defining a local BCS, and (3) demonstrates differences in the two BCSs for an example patient whose baseplate has rotational deviations due to imaging or surgical alignments. Differences in migration for the two BCSs ranged from about ±0.5 mm in translations and -0.4 deg to 0.7 deg in rotations. Differences were largest for deviations in internal-external rotation and smallest for deviations in varus-valgus rotation. An example demonstrated that the globally-aligned BCS resulted in migration being quantified as subsidence instead of liftoff, thereby changing fundamental interpretations. Because migrations computed using a local BCS are independent of imaging and surgical alignments and instead characterize migration using baseplate features, a local BCS enhances consistency in migration directions among patients and baseplate designs relative to the interface in which fixation may be compromised.
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Artroplastia de Reemplazo de Rodilla , Prótesis de la Rodilla , Humanos , Artroplastia de Reemplazo de Rodilla/métodos , Articulación de la Rodilla , Análisis Radioestereométrico , Tibia/diagnóstico por imagen , Tibia/cirugíaRESUMEN
INTRODUCTION: Dual mobility implants have been successful in reducing postoperative hip dislocation but mid-term results of cup migration and polyethylene wear are missing in the literature. Therefore, we measured migration and wear at 5-year follow-up using radiostereometric analysis (RSA). MATERIALS AND METHODS: A cohort of 44 patients (mean age 73, 36 female) with heterogeneous indications for hip arthroplasty but all with a high risk of hip dislocation received total hip replacement (THA) with The Anatomic Dual Mobility X3 monoblock acetabular construct and a highly crosslinked polyethylene liner. RSA images and Oxford Hip Scores were obtained perioperatively and 1, 2, and 5 years postoperatively. Cup migration and polyethylene wear were calculated using RSA. RESULTS: Mean 2-year proximal cup translation was 0.26 mm (95% CI 0.17; 0.36). Proximal cup translation was stable from 1- to 5-year follow-up. Mean 2-year cup inclination (z-rotation) was 0.23° (95% CI - 0.22; 0.68) and was greater in patients with osteoporosis compared to patients without osteoporosis (p = 0.04). Using 1-year follow-up as baseline, the 3D polyethylene wear rate was 0.07 mm/year (0.05; 0.10). Oxford hip scores improved 19 (95% CI 14; 24) points from mean 21 (range 4; 39) at baseline, to 40 (9; 48) 2 years postoperatively. There were no progressive radiolucent lines > 1 mm. There was 1 revision for offset correction. CONCLUSIONS: Anatomic Dual Mobility monoblock cups were well-fixed, the polyethylene wear rate was low, and the clinical outcomes were good until 5-year follow-up suggesting good implant survival in patients of different age groups and with heterogeneous indications for THA.
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Artroplastia de Reemplazo de Cadera , Luxación de la Cadera , Prótesis de Cadera , Humanos , Femenino , Polietileno , Luxación de la Cadera/cirugía , Falla de Prótesis , Diseño de Prótesis , Acetábulo/cirugía , Artroplastia de Reemplazo de Cadera/métodos , Estudios de SeguimientoRESUMEN
BACKGROUND AND PURPOSE: Dual-mobility hip arthroplasty utilizes a freely rotating polyethylene acetabular liner to protect against dislocation. As liner motion has not been confirmed in vivo, we undertook this using dynamic radiostereometry (RSA). PATIENTS AND METHODS: 6 patients with Anatomical Dual Mobility acetabular components were included. Markers were implanted in the liners using a drill guide. Static RSA recordings and patient-reported outcome measures were obtained postoperatively and at 1-year follow-up. Dynamic RSA recordings were obtained at 1-year follow-up during passive hip movement: abduction/external rotation, adduction/internal rotation (modified FABER-FADIR), to end-range and at 45° hip flexion. Liner and neck movements were described as anteversion, inclination, and rotation. RESULTS: Liner movement during modified FABER-FADIR was detected in 12 of 16 patients. Median (range) absolute liner movements were: anteversion 10° (5-20), inclination 6° (2-12), and rotation 11° (5-48) relative to the cup. Median absolute change in the resulting liner/neck angle (small articulation) was 28° (12-46) and in liner/cup angle (larger articulation) was 6° (4-21). Static RSA showed changes in median liner anteversion from 7° (-12 to 23) postoperatively to 10° (-3 to 16) at 1-year follow-up and inclination from 42° (35-66) postoperatively to 59° (46-80) at 1-year follow-up. Liner/neck contact was associated with high initial liner anteversion (p = 0.01). INTERPRETATION: The polyethylene liner moves over time. 1 year after surgery the liner can move with or without liner/neck contact. The majority of movement is in the smaller articulation between head and liner.
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Artroplastia de Reemplazo de Cadera , Prótesis de Cadera , Artroplastia de Reemplazo de Cadera/efectos adversos , Humanos , Polietileno , Análisis Radioestereométrico , Rango del Movimiento ArticularRESUMEN
Background and purpose - The Taperloc Complete hip is the successor of the Taperloc hip, aiming to increase range of motion and optimizing femoral fit with intermediate stem sizes. We evaluated whether these design changes affect fixation, and this RSA study compares 2-year migration. Patients and methods - In this prospective, multi-arm study, 100 patients were randomized to cementless total hip arthroplasty (THA) with Taperloc Complete full profile (TCFP), Taperloc Complete reduced distal (TCRD), Taperloc full profile (TFP), or Taperloc reduced distal (TRD). Migration was measured with model-based RSA postoperatively, and after 3, 12, and 24 months. Results - Results based on mixed-model analysis on 2-year postoperative RSA data from 74 patients showed similar subsidence (mm) in the first 3 months (mean [95% CI] TCFP 0.44 [0.20-0.69], TCRD 0.91 [0.40-1.42], TFP 0.71 [0.22-1.19], TRD 1.25 [0.58-1.91]) and stabilization afterwards. The TCFP showed statistically significantly less retroversion (°) at 2-year postoperatively compared with TFP and TCRD (mean [95% CI] TCFP: -0.13 [-0.64 to 0.38], TCRD: 0.84 [0.35-1.33], TFP: 0.56 [0.12-1.00], TRD: 0.37 [-0.35 to 1.09]). Interpretation - As expected in successful cementless THA, RSA shows stabilization after initial subsidence. Based on these results the Taperloc Complete stem is expected to have similar long-term fixation to the Taperloc stems. The reduced distal groups have larger, but statistically non-significant, initial migration compared with the TCFP group, which could be due to implantation in Dorr B, C femur types. It may be important to consider the femur shape for choosing a full profile or reduced distal stem to minimize migration.
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Artroplastia de Reemplazo de Cadera , Prótesis de Cadera , Artroplastia de Reemplazo de Cadera/efectos adversos , Artroplastia de Reemplazo de Cadera/métodos , Fémur/cirugía , Estudios de Seguimiento , Humanos , Estudios Prospectivos , Diseño de Prótesis , Falla de Prótesis , Análisis RadioestereométricoRESUMEN
BACKGROUND AND PURPOSE: In total knee arthroplasty (TKA), metal-backed (MBT) and all-polyethylene (APT) designs have shown comparable implant migration up to 2 years postoperatively using radiostereometric analysis (RSA). However, studies comparing mid-term migration of both designs are lacking. Furthermore, continuously migrating TKAs up to 2 years may continue to migrate or stabilize thereafter. Therefore, we compared 5-year migration of MBT and APT using either cruciate-stabilizing (CS) or posteriorstabilizing (PS) designs and specifically assessed migration profiles of continuously migrating TKAs beyond 2 years. PATIENTS AND METHODS: The present study includes results from 2 randomized trials comparing migration of cemented MBT with APT of either CS (CS study, n = 59) or PS (PS study, n = 56) design. 2 surgeons performed all surgeries. We used a linear mixed model for the analyses. RESULTS: The overall migration between MBT and APT TKAs was similar for either the CS or PS design over a 5-year period. In both studies combined, 9 implants showed continuous migration in the second postoperative year, of which 1 (APT-CS) was revised for instability, 4 (2 MBT-CS, MBT-PS, APT-PS) stabilized, and 4 (2 MBT-CS, APT-CS, MBT-PS) lacked 5-year data. INTERPRETATION: Overall migration was similar between MBT and APT TKAs up to 5 years, for both the CS and PS design. 4 initially migrating TKAs stabilized between 2- and 5-year follow-up, stressing the need for longer-term followup to determine whether second-year continuous migration correctly predicts loosening.
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Artroplastia de Reemplazo de Rodilla , Prótesis de la Rodilla , Osteoartritis de la Rodilla , Artroplastia de Reemplazo de Rodilla/efectos adversos , Artroplastia de Reemplazo de Rodilla/métodos , Estudios de Seguimiento , Humanos , Articulación de la Rodilla/cirugía , Prótesis de la Rodilla/efectos adversos , Osteoartritis de la Rodilla/cirugía , Diseño de Prótesis , Falla de Prótesis , Análisis Radioestereométrico , Ensayos Clínicos Controlados Aleatorios como AsuntoRESUMEN
BACKGROUND AND PURPOSE: Ceramic liners may reduce early stability of uncemented acetabular components due to higher stiffness. However, the bone ingrowth capacities of porous trabecular titanium might compensate for this effect. This prospective randomized trial quantifies migration patterns of the Delta-TT cup, and compares polyethylene and ceramic liners. PATIENTS AND METHODS: Patients undergoing primary uncemented total hip arthroplasty with the Delta-TT cup and femoral stem with ceramic head were randomized to a polyethylene (n = 25) or ceramic (n = 28) liner. Radiostereometric analysis (RSA) radiographs, patient-reported hip function (HOOS-PS, OHS), and quality of life (EQ5D) were collected at baseline and 1.5, 3, 6, 12, and 24 months postoperatively. Model-based RSA was used to calculate 3D cup translation and rotation, and mixed models were used to compare effects over time between groups. RESULTS: At 2 years follow-up, Delta-TT cups showed similar mean proximal translation of 0.56 mm (95% CI 0.38-0.75) in the ceramic (CE) group and 0.54 mm (0.30-0.77) in the polyethylene (PE) group, with a between group effect of 0.02 mm (-0.20-0.23). Most cup migration occurred in the first 1.5 to 3 months, stabilizing within 6 months. Any between-group effects were ≤ 0.30 mm for translation and ≤ 0.45° for rotation. Improvements in patient-reported hip function and quality of life were similar in both groups. INTERPRETATION: Regardless of liner type, Delta-TT cups showed some initial migration and stabilized within 6 months, which seems promising for long-term fixation in both cup-liner constructs.
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Artroplastia de Reemplazo de Cadera , Prótesis de Cadera , Artroplastia de Reemplazo de Cadera/efectos adversos , Cerámica , Humanos , Polietileno , Estudios Prospectivos , Diseño de Prótesis , Falla de Prótesis , Calidad de Vida , Análisis Radioestereométrico , TitanioRESUMEN
BACKGROUND: The number of revisions after TKA is expected to rise because of aging populations in many countries and because patients are undergoing TKA at younger ages. Aseptic loosening is a major reason for late revision, which can be predicted by radiostereometric analysis (RSA) of small groups of patients at 2 years of follow-up. RSA is therefore an ideal tool to assess new TKA designs before they are introduced to the market, although not every TKA design has been studied with RSA. If RSA-tested TKA designs have lower 10-year revision rates in national registries than non-RSA-tested TKA designs, RSA testing of all new designs could be advocated. QUESTIONS/PURPOSES: In this study, we asked: Is there a difference in the all-cause revision rate between non-RSA-tested and RSA-tested TKA designs registered in national knee arthroplasty registries at 5 and 10 years of follow-up? METHODS: Knee arthroplasty registries were identified through the European Federation of National Associations of Orthopaedics and Traumatology webpage and through a manual internet search. Inclusion criteria were a minimum follow-up duration of 10 years and available revision or survival data per TKA design. Twenty-six registries were identified; seven were included comprising 339 TKA designs, of which 236 designs were classified as RSA-tested and 103 as non-RSA-tested. Six registries were excluded because no report was published. One registry was excluded because no fixation method was mentioned (79 TKA designs). Another registry was excluded because there was no 10-year data available (22 non-RSA-tested designs; 10 RSA-tested designs). Eleven registries were excluded because they did not provide revision rates per design and had not reached 10 years follow-up. The revision rates with their standard errors were extracted per design. We used the data from a recent meta-analysis to identify whether a TKA design was previously tested with RSA. This meta-analysis found 53 RSA studies comprising 70 different TKA designs. The prosthesis model, fixation method and insert type were extracted from these RSA-studies. The design characteristics of the TKA reported in the knee arthroplasty registries were also extracted, and if possible, matched to the TKA designs reported in the RSA-studies. At 5 years of follow-up, 191 TKA designs were identified as non-RSA-tested and 92 were identified as RSA-tested. At 10 years of follow-up, 154 TKA designs and 74 TKA designs were classified as non-RSA-tested and RSA-tested, respectively. A random-effects model using the Metafor Package in R statistics was used to estimate the pooled revision rate at 5 and 10 years of follow-up for both groups. The difference in revision rates between groups at 5 and 10 years of follow-up was estimated by including RSA as a factor in the random-effects model. RESULTS: Mean all-cause revision rates at 5 years for non-RSA-tested and RSA-tested implants were 3.6% (95% CI 3.4 to 3.8) and 2.9% (95% CI 2.7 to 3.0), with a mean difference of 0.6% favoring RSA-tested implants (95% CI 0.4 to 0.8; p < 0.001). Mean all-cause revision rates at 10 years for non-RSA-tested and RSA-tested implants were 5.5% (95% CI 5.2 to 5.9) and 4.4% (95% CI 4.1 to 4.7), with a mean difference of 0.9% favoring RSA-tested implants (95% CI 0.4 to 1.3; p < 0.001). CONCLUSIONS: Although there are exceptions, across registries, TKA designs that have been tested in an RSA setting have a slightly lower (about 1%) mean all-cause revision rate at 5-year and 10-year follow-up than those tested in a non-RSA setting. Acknowledging the inherent limitations of this observational study, a risk difference of 1% could potentially translate into an approximate 20% decrease in revision burden up to 10 years, which may have a profound impact on patient morbidity and health-related costs. LEVEL OF EVIDENCE: Level III, therapeutic study.
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Artroplastia de Reemplazo de Rodilla/instrumentación , Análisis de Falla de Equipo , Articulación de la Rodilla/cirugía , Prótesis de la Rodilla , Complicaciones Posoperatorias/cirugía , Falla de Prótesis , Análisis Radioestereométrico , Reoperación , Anciano , Artroplastia de Reemplazo de Rodilla/efectos adversos , Fenómenos Biomecánicos , Femenino , Humanos , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/fisiopatología , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/diagnóstico por imagen , Complicaciones Posoperatorias/fisiopatología , Diseño de Prótesis , Recuperación de la Función , Sistema de Registros , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Resultado del TratamientoRESUMEN
Background and purpose - The uncemented Symax hip stem has shown early proximal ingrowth as result of the BONIT-hydroxyapatite (HA) coating and the distal DOTIZE surface treatment. We evaluated 2-year postoperative radiostereometric analysis (RSA) migration of the Symax hip stem in THA patients. We also investigated the correlation between migration at 4 weeks and clinical outcomes after 2 years.Patients and methods - Patients in a 2-year clinical follow-up single-centre RSA randomized controlled trial were randomized to 2 different cup designs. All 45 patients received a Symax hip stem. RSA migration patterns of the Symax hip stem is presented here as a single cohort. RSA examinations were performed postoperatively, but before weight-bearing, and subsequently after 1, 3, 6, 12, and 24 months. Clinical outcomes and radiographic evaluations were assessed 3, 6, 12, and 24 months postoperatively.Results - During the first 4 weeks, the Symax hip stem subsided, rotated into retroversion, and translated posteriorly, after which the migration ceased and the prosthesis stabilized. All clinical outcomes improved from preoperatively to 2 years. There was no clinically or statistically significant correlation between subsidence and retroversion at 4 weeks and clinical outcomes after 2 years.Interpretation - RSA evaluation of the uncemented Symax hip stem confirms that the design principles and coating properties lead to early stabilization of the stem, as early as 4 weeks postoperatively. There was no correlation between subsidence and retroversion at 4 weeks and clinical outcomes after 2 years. Based on the predictive potential of the RSA technique, we anticipate excellent long-term survival of this hip stem.
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Artroplastia de Reemplazo de Cadera/métodos , Prótesis de Cadera/efectos adversos , Falla de Prótesis/etiología , Adulto , Anciano , Artroplastia de Reemplazo de Cadera/efectos adversos , Artroplastia de Reemplazo de Cadera/instrumentación , Cementación , Materiales Biocompatibles Revestidos , Durapatita , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Osteoartritis de la Cadera/cirugía , Complicaciones Posoperatorias/diagnóstico por imagen , Diseño de Prótesis , Radiografía , Análisis Radioestereométrico , Rotación , Resultado del TratamientoRESUMEN
Background and purpose - Little is known about the long-term migration pattern of cementless stems in total hip arthroplasty (THA). Furthermore, the role of bioactive coatings in fixation, and thus migration, remains uncertain. Hydroxyapatite (HA) is the most commonly used bioactive coating. However, delamination of the coating might induce loosening. Alternatively, fluorapatite (FA) has proved to be more thermostable than HA, thereby potentially increasing longevity. We assessed the long-term migration of cementless stems with different coatings using radiostereometric analysis (RSA), thereby establishing a reference for acceptable migration. Patients and methods - 61 THAs in 53 patients were randomized to receive either a HA, FA, or uncoated Mallory-Head Porous stem during the years 1992 to 1994. Primary outcome was stem migration measured using RSA and secondary outcome was the Harris Hip Score (HHS). Evaluation took place preoperatively and postoperatively on the second day, at 6, 12, 25 and 52 weeks, and annually thereafter. At the 25-year follow-up, 12 patients (17 THAs) had died and 1 patient (1 THA) was lost to follow-up. Due to the high number of missing second-day postoperative RSA radiographs, the 1-year postoperative RSA radiograph was used as baseline for the comparative analyses. Results - Mean follow-up was 17 years (SD 6.6). All stems showed initial rapid migration with median subsidence of 0.2 mm (-0.1 to 0.6) and median retroversion of 0.9° (-3.2 to 2) at 12 months, followed by stable migration reaching a plateau phase. No stem was revised, albeit 1 stem showed continuous subsidence up to 1.5 mm. Comparing the different coatings, we could not find a statistically significant difference in overall 25-year migration (p-values > 0.05). Median subsidence at 15-year follow-up was for HA -0.1 mm (-0.4 to 0.2), for FA 0 mm (-0.1 to 0.2), and for uncoated stems 0.2 mm (-0.1 to 0.5). Median internal rotation at 15-year follow-up was for HA not available, for FA 1.1° (-0.5 to 2.6), and for uncoated stems 0° (-0.5 to 0.4). HHS were also comparable (p-values > 0.05), with at 15-year follow-up for HA 85 points (41-99), for FA 76 points (61-90), and for uncoated stems 79 points (74-90). Interpretation - The long-term migration pattern of cementless stems using different bioactive coatings has not previously been described. No beneficial effect, or side effect at long-term follow-up of bioactive coatings, was found. The provided migration data can be used in future research to establish thresholds for acceptable migration patterns cementless stem designs.
Asunto(s)
Apatitas/farmacología , Artroplastia de Reemplazo de Cadera , Durapatita/farmacología , Fémur/diagnóstico por imagen , Efectos Adversos a Largo Plazo , Complicaciones Posoperatorias , Falla de Prótesis/etiología , Anciano , Artroplastia de Reemplazo de Cadera/efectos adversos , Artroplastia de Reemplazo de Cadera/instrumentación , Artroplastia de Reemplazo de Cadera/métodos , Materiales Biocompatibles Revestidos/farmacología , Femenino , Estudios de Seguimiento , Prótesis de Cadera/efectos adversos , Humanos , Efectos Adversos a Largo Plazo/diagnóstico , Efectos Adversos a Largo Plazo/etiología , Masculino , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/etiología , Diseño de Prótesis/efectos adversos , Diseño de Prótesis/métodos , Análisis Radioestereométrico/métodosRESUMEN
Background and purpose - The all-polyethylene tibial (APT) component, introduced in the early 1970s, was surpassed by metal-backed tibial (MBT) trays as the first choice for total knee arthroplasty (TKA). With improved polyethylene, the modern APT components can reduce costs, and have shown equivalent results in survivorship and early migration of the cruciate-retaining and cruciate-stabilizing designs. This study compares the 2-year migration of a similarly designed APT-posterior stabilized (PS) and a MBT-PS TKA, using radiostereometric analysis (RSA).Patients and methods - 60 patients were randomized to receive either an APT Triathlon PS or an MBT Triathlon PS TKA (Stryker, NJ, USA). Migration measured by RSA and clinical scores were evaluated at baseline and at 3, 12, and 24 months postoperatively. Repeated measurements were analyzed with a linear mixed model and generalized estimating equations.Results - The mean maximum total point movement (MTPM) at 3, 12, and 24 months was 0.41 mm (95% CI 0.33-0.50), 0.57 mm (0.44-0.70), and 0.56 mm (0.42-0.69) respectively in the MBT group and 0.46 mm (0.36-0.57), 0.61 mm (0.49-0.73), and 0.64 mm (0.50-0.77) in the APT group. 2 MBT and 1 APT implant were considered unstable at the 2-year follow-up. The KSS Knee score and KSS Function across 3, 12, and 24 months were comparable in both groups.Interpretation - For an APT-PS designed component, MTPM measured with RSA is comparable to the MBT-PS component after 2 years of follow-up. No differences in complications or clinical outcomes were found.
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Artroplastia de Reemplazo de Rodilla/instrumentación , Articulación de la Rodilla/diagnóstico por imagen , Prótesis de la Rodilla , Diseño de Prótesis , Análisis Radioestereométrico , Anciano , Femenino , Humanos , Masculino , Medición de Resultados Informados por el Paciente , PolietilenoRESUMEN
Background and purpose - Hydroxyapatite (HA)-coated implants have been associated with high polyethylene wear in hip arthroplasties. HA coating as a promoter of wear in knee arthroplasties has not been investigated. We compared the wear-rate of the polyethylene bearing for cemented and cementless HA-coated Oxford medial unicondylar knee arthroplasties (UKA). Secondarily, we investigated whether wear-rates were influenced by overhang or impingement of the bearing. Patients and methods - 80 patients (mean age 64 years), treatment-blinded, were randomized to 1 of 3 Oxford medial UKA versions: cemented with double-pegged or single-pegged femoral component or cementless HA-coated with double-pegged femoral component (ratios 1:1:1). We compared wear between the cemented (n = 55) and cementless group (n = 25) (ratio 2:1). Wear, impingement, and overhang were quantified between surgery and 5-year follow-up using radiostereometry. Clinical outcome was evaluated with the Oxford Knee Score. Results - The mean wear-rate for patients without bearing overhang was 0.04 mm/year (95% CI 0.02-0.07) for the cemented group and 0.05 mm/year (CI 0.02-0.08) for the cementless group. The mean difference in wear was 0.008 mm/year (CI -0.04 to 0.03). No impingement was identified. Half of the patients had medial bearing overhang, mean 2.5 mm (1-5). Wear increased by 0.014 mm/year for each mm increment in overhang. The mean Oxford Knee Score was 39 for the cementless group and 38 for the cemented group at the 5-year follow-up. Interpretation - The wear-rates were similar for the 2 fixation methods, which supports further use of the cementless Oxford medial UKA. However, a caveat is a relatively large 95% CI of the mean difference in wear-rate. Component size and position is important as half of the patients presented with an additional increase in wear-rate due to medial bearing overhang.
Asunto(s)
Artroplastia de Reemplazo de Rodilla , Cementos para Huesos/uso terapéutico , Prótesis de la Rodilla/efectos adversos , Polietileno/uso terapéutico , Artroplastia de Reemplazo de Rodilla/efectos adversos , Artroplastia de Reemplazo de Rodilla/instrumentación , Artroplastia de Reemplazo de Rodilla/métodos , Cementación/métodos , Materiales Biocompatibles Revestidos/uso terapéutico , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Osteoartritis de la Rodilla/cirugía , Diseño de Prótesis , Falla de Prótesis , Análisis Radioestereométrico , Resultado del TratamientoRESUMEN
Background and purpose - Pooling data of studies evaluating total knee arthroplasty migration using radiostereometric analysis (RSA) may be compromised when the RSA method used would influence estimated differences between groups. We therefore reanalyzed a marker-based RSA study with model-based RSA to assess possible limitations of each RSA method, including insert micromotions in modular TKA and their effect on estimated group differences. Patients and methods - All patients had received a cemented Triathlon implant (Stryker, Mahwah, NJ, USA) with either an all-polyethylene (n = 29) or a metal-backed (n = 28) tibial component. The latter group was reanalyzed with model-based RSA. Precision of each RSA method was calculated using double examinations. Bland-Altman plots were constructed to determine the limits of agreement between the 2 RSA methods. Polyethylene insert micromotion was quantified by measuring migration with respect to the metal tray. Finally, analyses of the original study were repeated with the model-based RSA results. Results - Systematic differences were found in translations between marker-based and model-based RSA as a result of different reference origins being used for migration calculations. Micromotions of the polyethylene insert within the metal tray were negligibly small. Mean migration results were comparable between marker-based and model-based RSA when using the same reference origin, even though conclusions on individual patients may differ between RSA methods due to various types of measurement error (e.g., marker occlusion and model-fit inaccuracies). Interpretation - At least for the studied TKA design, pooling mean migration data of different RSA methods appears justified. For translations, however, adjustments should be made to correct for differences in reference origin. Migration patterns of individual patients may differ as a result of distinct types of measurement error.
Asunto(s)
Artroplastia de Reemplazo de Rodilla/efectos adversos , Prótesis de la Rodilla/efectos adversos , Falla de Prótesis , Biomarcadores , Humanos , Análisis Radioestereométrico , Factores de TiempoRESUMEN
Frailty is highly prevalent in the elderly, increasing the risk of poor health outcomes. The Groningen Frailty Indicator (GFI) is a 15-item validated questionnaire for the elderly. Its value in patients with end-stage hip or knee osteoarthritis (OA) has not yet been determined. This study assesses the validity of the GFI in this patient group. End-stage hip or knee OA patients completed the GFI (range 0-15, ≥ 4 = frail) before arthroplasty surgery. Convergent validity was determined by Spearman-rank correlation between the SF-12 physical (PCS) and mental (MCS) component scores and the physical and mental GFI-domains, respectively. Discriminant validity was assessed by means of overall GFI-score and the pain-domain of the Hip/Knee Osteoarthritis Outcome Score (HOOS/KOOS). Altogether 3275 patients were included of whom 2957 (90.3%) completed the GFI. Mean GFI-scores were 2.78 (2.41) and 2.28 (1.99) in hip and knee OA-patients, respectively, with 570 (35.9%) of hip and 344 (24.1%) of knee patients considered frail. The convergent validity was moderate to strong (physical domain R = - 0.4, mental domain R = - 0.6) and discriminant validity low (R HOOS/KOOS-pain domain = - 0.2), confirming the validity of the GFI-questionnaire in this population. With 90% of participants completing the GFI, it is a feasible and valid questionnaire to assess frailty in end-stage hip and knee OA-patients. One-third (33.3%) of the patients undergoing hip arthroplasty and a quarter (24.1%) of those undergoing knee arthroplasty are frail. Whether this is associated with worse outcomes and can thus be used as a pre-operative predictor needs to be explored.
Asunto(s)
Fragilidad/diagnóstico , Osteoartritis de la Cadera/diagnóstico , Osteoartritis de la Rodilla/diagnóstico , Encuestas y Cuestionarios , Actividades Cotidianas , Factores de Edad , Anciano , Evaluación de la Discapacidad , Estudios de Factibilidad , Femenino , Anciano Frágil , Fragilidad/fisiopatología , Fragilidad/psicología , Estado de Salud , Humanos , Masculino , Salud Mental , Persona de Mediana Edad , Países Bajos , Osteoartritis de la Cadera/fisiopatología , Osteoartritis de la Cadera/psicología , Osteoartritis de la Cadera/cirugía , Osteoartritis de la Rodilla/fisiopatología , Osteoartritis de la Rodilla/psicología , Osteoartritis de la Rodilla/cirugía , Dimensión del Dolor , Valor Predictivo de las Pruebas , Pronóstico , Calidad de Vida , Reproducibilidad de los ResultadosAsunto(s)
Artroplastia de Reemplazo de Rodilla , Procedimientos de Cirugía Plástica , Procedimientos Quirúrgicos Robotizados , Robótica , Artroplastia de Reemplazo de Rodilla/efectos adversos , Humanos , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/cirugía , Procedimientos Quirúrgicos Robotizados/efectos adversosRESUMEN
Background and purpose - Implant inducible micromotions have been suggested to reflect the quality of the fixation interface. We investigated the usability of dynamic RSA for evaluation of inducible micromotions of the Oxford Unicompartmental Knee Arthroplasty (UKA) tibial component, and evaluated factors that have been suggested to compromise the fixation, such as fixation method, component alignment, and radiolucent lines (RLLs). Patients and methods - 15 patients (12 men) with a mean age of 69 (55-86) years, with an Oxford UKA (7 cemented), were studied after a mean time in situ of 4.4 (3.6-5.1) years. 4 had tibial RLLs. Each patient was recorded with dynamic RSA (10 frames/second) during a step-up/step-down motion. Inducible micromotions were calculated for the tibial component with respect to the tibia bone. Postoperative component alignment was measured with model-based RSA and RLLs were measured on screened radiographs. Results - All tibial components showed inducible micromotions as a function of the step-cycle motion with a mean subsidence of up to -0.06 mm (95% CI: -0.10 to -0.03). Tibial component inducible micromotions were similar for cemented fixation and cementless fixation. Patients with tibial RLLs had 0.5° (95% CI: 0.18-0.81) greater inducible medio-lateral tilt of the tibial component. There was a correlation between postoperative posterior slope of the tibial plateau and inducible anterior-posterior tilt. Interpretation - All patients had inducible micromotions of the tibial component during step-cycle motion. RLLs and a high posterior slope increased the magnitude of inducible micromotions. This suggests that dynamic RSA is a valuable clinical tool for the evaluation of functional implant fixation.
Asunto(s)
Artroplastia de Reemplazo de Rodilla/métodos , Articulación de la Rodilla/diagnóstico por imagen , Prótesis de la Rodilla , Falla de Prótesis/etiología , Anciano , Artroplastia de Reemplazo de Rodilla/efectos adversos , Fenómenos Biomecánicos , Cementos para Huesos , Cementación , Prueba de Esfuerzo/métodos , Femenino , Estudios de Seguimiento , Humanos , Articulación de la Rodilla/fisiopatología , Articulación de la Rodilla/cirugía , Prótesis de la Rodilla/efectos adversos , Masculino , Persona de Mediana Edad , Movimiento (Física) , Medición de Resultados Informados por el Paciente , Diseño de Prótesis , Análisis Radioestereométrico/métodos , Tibia/diagnóstico por imagenRESUMEN
Background and purpose - Stability and survival of cemented total hip prostheses is dependent on a multitude of factors, including the type of cement that is used. Bone cements vary in viscosity, from low to medium and high. There have been few clinical RSA studies comparing the performance of low- and high-viscosity bone cements. We compared the migration behavior of the Stanmore hip stem cemented using novel low-viscosity Palamed bone cement with that of the same stem cemented with conventional high-viscosity Palacos bone cement. Patients and methods - We performed a randomized controlled study involving 39 patients (40 hips) undergoing primary total hip replacement for primary or secondary osteoarthritis. 22 patients (22 hips) were randomized to Palacos and 17 patients (18 hips) were randomized to Palamed. Migration was determined by RSA. Results - None of these 40 hips had been revised at the 10-year follow-up mark. To our knowledge, the patients who died before they reached the 10-year endpoint still had the implant in situ. No statistically significant or clinically significant differences were found between the 2 groups for mean translations, rotations, and maximum total-point motion (MTPM). Interpretation - We found similar migration of the Stanmore stem in the high-viscosity Palacos cement group and the low-viscosity Palamed cement group. We therefore expect that the risk of aseptic loosening with the new Palamed cement would be comparable to that with the conventional Palacos cement. The choice of which type of bone cement to use is therefore up to the surgeon's preference.
Asunto(s)
Artroplastia de Reemplazo de Cadera/métodos , Cementos para Huesos , Prótesis de Cadera , Polimetil Metacrilato , Anciano , Femenino , Estudios de Seguimiento , Humanos , Masculino , Diseño de Prótesis , Estudios Retrospectivos , Factores de TiempoRESUMEN
Aims: The aim of this study was to compare the migration of the femoral component, five years postoperatively, between patients with a highly cross-linked polyethylene (HXLPE) insert and those with a conventional polyethylene (PE) insert in an uncemented Triathlon fixed insert cruciate-retaining total knee arthroplasty (TKA). Secondary aims included clinical outcomes and patient-reported outcome measures (PROMs). We have previously reported the migration and outcome of the tibial components in these patients. Methods: A double-blinded randomized controlled trial was conducted including 96 TKAs. The migration of the femoral component was measured with radiostereometry (RSA) at three and six months and one, two, and five years postoperatively. PROMs were collected preoperatively and at all periods of follow-up. Results: There was no clinically relevant difference in terms of migration of the femoral component or PROMs between the HXLPE and PE groups. The mean difference in migration (maximum total point motion), five years postopeatively, was 0.04 mm (95% CI -0.06 to 0.16) in favour of the PE group. Conclusion: There was no clinically relevant difference in migration of the femoral component, for up to five years between the two groups. These findings will help to establish a benchmark for future studies on migration of femoral components in TKA.