Primary outcomes of a femoral neck-preserving stem: a multicentre clinical-radiological analysis at 5-year follow-up.

PURPOSE: The aim of this prospective study was to evaluate the clinical-radiological outcomes of the Alteon Neck Preserving Stem (ANPS) (Exactech, Gainesville, FL, USA) implanted in four different centres by five senior hip surgeons with a minimum of 5 years of follow-up. MATERIAL AND METHOD: We conducted a multicentre prospective study that analysed 155 consecutive total hip replacements during 2014. We performed clinical-radiological analysis measuring Harris Hip Score (HHS), subjective satisfaction evaluation, radiolucencies, position of components, limb length discrepancy, heterotopic ossification, medical and surgical complications and a survival analysis at 5 years follow-up. RESULTS: Thigh pain was reported in 5 cases (3.2%), 2 of which reported mild pain, 2 moderate, and 1 severe. In 2 cases, subsidences of 3 mm were detected in the first scheduled X-ray, both related to intraoperative fractures with no progression after 3 months. The overall complication rate was 5.8% and 6 of the 9 complications were in the first 30 cases. Mean HHS improved from 42.9 points (range 37.2-55.7 points) preoperatively to 94.9 on average (range 87-98) at the end of the follow-up (p <0.01). Subjective evaluation was excellent in 130 (83.87%) cases and good in 25 patients (16.13%). CONCLUSIONS: The clinical-radiographic results of ANPS THR are satisfactory. The mid-term results are promising. However, long-term follow-up studies are necessary to confirm the validity of the concept.

4- to 8-year complication analysis of 2 'partial collum' femoral stems in primary THA.

OBJECTIVES: Compare the clinical and radiological outcome of CFP stem with the MiniHip design in a prospective series, with special interest in intraoperative periprosthetic fracture (IPPF). METHODS: We prospectively followed 101 cases treated with the MiniHip stem (Group 1) and 89 with the CFP stem (Group 2) operated between 2010 and 2014. No significant demographic differences were observed between both groups. Median follow-up was 72 months. Average stem length was 41% shorter in the MiniHip group (p < 0.001). Radiological parameters were measured and a logistcic regression model was created to evaluate factors associated with IPPF. RESULTS: Mean mHHS improved from 54 to 95 in the MiniHip group (p < 0.001) and from 64 to 98 in the CFP group (p < 0.001). No significant differences were observed in terms of loosening, infection or instability. We observed 7 IPPFs (3.68%), 3 in group 1 and 4 in group 2. After adjusting for confounders, CFP was not associated with a greater risk of IPPF (OR 3.23; 95% CI, 0.250-42.034, p = 0.368), however, a more complex fracture pattern was observed with this stem design. Prior acetabular fractures were associated with IPPF (OR 66.85; 95% CI, 1.142-3911, p = 0.043). Compared to Dorr A femurs, type Dorr B appeared protective against IPPF (OR 0.039; 95% CI, 0.001-1.109, p = 0.058). Valgus alignment tended to increase the risk of IPPF (OR 20.59; 95% CI 0.870-487.221, p = 0.061). CONCLUSIONS: MiniHip showed similar radiological outcomes to CFP at short- to mid-term follow-up without increasing IPPFs with a shorter stem length. Given that CFP produced a more complex IPPF pattern, surgeons should be cautious with alignment of this particular design, especially in Dorr A femur.

[Use of metaphyseal stems «Proxima¼ DePuy: our experience to more than five years]. / Utilización de los vástagos metafisarios «Próxima¼ DePuy: nuestra experiencia a más de cinco años.

The total hip arthroplasty with short stems to preserve bone is a good choice in young patients that expected future revision surgery, it is also a good choice when we use approaches for minimal invasive surgeries. In this study, we have evaluated, clinically and radiologically, our experience in total hip arthroplasty with the use of short stems and metaphyseal anchorage. In total we have involved 23 patients with a mean age of 50.2 years (range 45 to 69 y/o) at the time of surgery. The median follow-up was greater than five years. There was a slight Varus femoral stem in three cases, one of them in severe varus. The latter presented continuous pain in the lateral aspect of the thigh that increased with time, with a diaphyseal reaction and an increase in radiolucencies around the stem that required revision surgery 12 months postoperative. A longer follow-up is required to analyze the results and confirm the durability of the observed clinical findings. Patients were evaluated radiological and clinically using the scale of Merle dAubigné (MD).

La artroplastía total de cadera con los vástagos cortos encaminada a preservar el hueso es una buena opción en pacientes jóvenes a quienes se les prevé futuras cirugías de revisión. También es una buena elección cuando se utilizan cirugías con abordajes miniinvasivos. En este estudio clínico y radiológico hemos evaluado nuestra experiencia en el uso de artroplastía total de cadera con vástagos cortos de anclaje metafisario tipo DePuy Próxima. En total se han intervenido 23 pacientes con una edad media de 50.2 años (rango de 45 a 69 años) en el momento de la cirugía. El seguimiento medio fue de más de cinco años. Hubo un ligero varo del tallo femoral en tres casos, uno de ellos en varo severo. Este último caso presentó dolor continuo en las caras laterales del muslo que aumentó con el tiempo junto con una reacción diafisaria y un aumento en el tallo que requirió cirugía de revisión a los 12 meses postoperatorios. Se requiere un seguimiento más prolongado para analizar los resultados y confirmar la durabilidad de los resultados clínicos observados. Los pacientes fueron evaluados radiológica y clínicamente utilizando el baremo de Merle dAubigné (MD).

Utilización de los vástagos metafisarios «Próxima¼ DePuy: nuestra experiencia a más de cinco años / Use of metaphyseal stems «Proxima¼ DePuy: our experience to more than five years

Resumen: La artroplastía total de cadera con los vástagos cortos encaminada a preservar el hueso es una buena opción en pacientes jóvenes a quienes se les prevé futuras cirugías de revisión. También es una buena elección cuando se utilizan cirugías con abordajes miniinvasivos. En este estudio clínico y radiológico hemos evaluado nuestra experiencia en el uso de artroplastía total de cadera con vástagos cortos de anclaje metafisario tipo DePuy Próxima. En total se han intervenido 23 pacientes con una edad media de 50.2 años (rango de 45 a 69 años) en el momento de la cirugía. El seguimiento medio fue de más de cinco años. Hubo un ligero varo del tallo femoral en tres casos, uno de ellos en varo severo. Este último caso presentó dolor continuo en las caras laterales del muslo que aumentó con el tiempo junto con una reacción diafisaria y un aumento en el tallo que requirió cirugía de revisión a los 12 meses postoperatorios. Se requiere un seguimiento más prolongado para analizar los resultados y confirmar la durabilidad de los resultados clínicos observados. Los pacientes fueron evaluados radiológica y clínicamente utilizando el baremo de Merle d'Aubigné (MD).

Abstract: The total hip arthroplasty with short stems to preserve bone is a good choice in young patients that expected future revision surgery, it is also a good choice when we use approaches for minimal invasive surgeries. In this study, we have evaluated, clinically and radiologically, our experience in total hip arthroplasty with the use of short stems and metaphyseal anchorage. In total we have involved 23 patients with a mean age of 50.2 years (range 45 to 69 y/o) at the time of surgery. The median follow-up was greater than five years. There was a slight Varus femoral stem in three cases, one of them in severe varus. The latter presented continuous pain in the lateral aspect of the thigh that increased with time, with a diaphyseal reaction and an increase in radiolucencies around the stem that required revision surgery 12 months postoperative. A longer follow-up is required to analyze the results and confirm the durability of the observed clinical findings. Patients were evaluated radiological and clinically using the scale of Merle d'Aubigné (MD).

A proposal for the study of cementless short-stem hip prostheses / Una propuesta para el estudio de prótesis de cadera de vástago corto

Abstract: Background: With the recent evolution of hip arthroplasty, new models of short stems have emerged. So far, we do not have a clear strategy to analyze their outcomes, since there is confusion around the definition of short stem and there is no consensus for their classification. Purposes: The purpose of this study was to review the current state of the art of cementless short stems considering the main design characteristics; it provides a definition of short stem and proposes a classification, grouping them into families by means of a nomenclature that describes them accurately. Material and methods: We conducted a search in the PubMed and Scopus databases and consulted various implant manufacturers, foundations devoted to research on joint arthroplasty, organizations of independent experts on medical device analysis, and national arthroplasty registries. The stems studied were classified according to a new nomenclature system. Conclusions: We identified 44 different models that share 84 design variables and may be grouped into three types and 16 generic families. The stems were manufactured by 20 different companies. Short stems are those occupying the neck, metaphysis and the proximal aspect of the limit between the metaphysis and diaphysis, regardless of the geometric type of endosteum present. A wide variety of models was identified, with multiple design variables. In order to classify them, it was necessary to design a whole new nomenclature capable of describing them in an unequivocal, unique and distinctive way.

Resumen: Antecedentes: Con la reciente evolución de la artroplastia de cadera han surgido nuevos modelos con componentes femorales cortos. Aún no se tiene una forma clara de analizar sus resultados pues existe confusión en las definiciones y no tenemos una clasificación universal. Objetivos: Revisar el estado del arte de los componentes femorales cortos no cementados, considerar sus características de diseño, tratar de establecer una clasificación y una nomenclatura que permita una mejor definición del implante. Material y métodos: Realizamos una búsqueda en PubMed y Scopus, consultamos a varios fabricantes, fundaciones dedicadas a la investigación en artroplastías, organizaciones dedicadas al análisis de los implantes y algunos registros nacionales de artroplastías. Los componentes femorales estudiados se agruparon en esta clasificación propuesta. Conclusiones: Identificamos 3 tipos y 16 familias genéricas de implantes, se logró establecer una clasificación que generó una nueva nomenclatura que permite la identificación específica de cada uno de los diseños.

A proposal for the study of cementless short-stem hip prostheses.

BACKGROUND: With the recent evolution of hip arthroplasty, new models of short stems have emerged. So far, we do not have a clear strategy to analyze their outcomes, since there is confusion around the definition of short stem and there is no consensus for their classification. PURPOSES: The purpose of this study was to review the current state of the art of cementless short stems considering the main design characteristics; it provides a definition of short stem and proposes a classification, grouping them into families by means of a nomenclature that describes them accurately. MATERIAL AND METHODS: We conducted a search in the PubMed and Scopus databases and consulted various implant manufacturers, foundations devoted to research on joint arthroplasty, organizations of independent experts on medical device analysis, and national arthroplasty registries. The stems studied were classified according to a new nomenclature system. CONCLUSIONS: We identified 44 different models that share 84 design variables and may be grouped into three types and 16 generic families. The stems were manufactured by 20 different companies. Short stems are those occupying the neck, metaphysis and the proximal aspect of the limit between the metaphysis and diaphysis, regardless of the geometric type of endosteum present. A wide variety of models was identified, with multiple design variables. In order to classify them, it was necessary to design a whole new nomenclature capable of describing them in an unequivocal, unique and distinctive way.

Con la reciente evolución de la artroplastia de cadera han surgido nuevos modelos con componentes femorales cortos. Aún no se tiene una forma clara de analizar sus resultados pues existe confusión en las definiciones y no tenemos una clasificación universal.

Aseptic loosening rate of the Mayo femoral stem with medium-term follow up.

The aseptic loosening rate of the Mayo hip prosthesis femoral stem was determined in a 44 patient (52 hips) series, by comparing preoperative and postoperative clinical and radiographic parameters, over a minimal 5-year postoperative period. Loosening was obvious before five years in four hips (7.6%), while the stem was considered stable in the remaining 48 hips over a mean 6.1 year period, therefore accounting for a 92.3% Kaplan-Meier survival rate. We conclude that the aseptic loosening rate is too high for the Mayo hip prosthesis femoral stem, as compared to literature data concerning the non-conservative stems.