Reverse oblique intertrochanteric femoral fractures treated with the gamma nail.

We studied 47 reverse oblique intertrochanteric femoral fractures that were treated with gamma nails between 1992 and 2000. Fracture reduction was satisfactory in 38 patients (81%), the hip screw position was correct in 42 (89%) and there were no peri-operative complications. However, in three patients the nail displaced, resulting in non-union in one and protrusion into the acetabulum in another. A logistical regression analysis of our series showed that an incorrect position of the hip screw in the femoral head was the only predictor for complications. Thus, we consider that the gamma nail is a good option for the treatment of these complex fractures.

Extensively hydroxyapatite-coated stems in revision hip arthroplasty: A radiological mid-term follow-up study.

Femoral revision surgery involves the placement of a stable stem and the regeneration of the damaged bone structure. We retrospectively reviewed 36 cases of femoral revision surgery in which an extensively hydroxyapatite-coated porous stem was implanted with a five-year minimum follow-up. Nine of the cases had type I defects, 12 had type II defects, six had III-A defects and nine had III-B defects. The mean follow-up was 7.7 years (range 5-11). No cases of revision surgery, subsidence or displacement were detected. In 35 cases the integration of the stem had been achieved, the bone structure had been restored and there was no fibrous interface visible between the implant and the bone. The fully hydroxyapatite-coated stems thus proved a valuable alternative for femoral revision surgery in mild and moderate bone defects. (Hip International 2005; 15: 38-45).

Cirugía asistida con ordenador en las artroplastias de rodilla. Estudio prospectivo / Computer-assisted surgery in knee arthroplasty. Prospective study

Objetivo. Estudiar la utilidad de un sistema inalámbrico de cirugía asistida por ordenador (navegación quirúrgica) para la implantación de prótesis de rodilla. Material y método. Estudio prospectivo y aleatorizado. Se han analizado 40 pacientes a los que se les implantó una prótesis de rodilla: en un grupo de 20 pacientes se utilizó un sistema de navegación inalámbrico y en otro, también de 20 pacientes, la técnica estándar con alineación instrumentada manual. Sobre una tomografía computarizada de la extremidad, tomada en el período postoperatorio inmediato, se midió el ángulo femoral (formado entre el eje mecánico del fémur y el componente femoral), el ángulo tibial (formado entre el eje mecánico tibial y la plataforma tibial) y el ángulo femorotibial (formado entre los ejes mecánicos femoral y tibial).Resultados. En el grupo sin navegador el ángulo femoral osciló entre 90º y 94º, con una media de 91,7º; el ángulo tibial se situó entre 87º y 95º, con una media de 90,2º; y el angulo femorotibial varió de 172º a 180º, con una media de 175,9º, lo que indica un ligero predominio de la desviación en varo del eje mecánico de la extremidad. En el grupo con navegador el ángulo femoral se situó entre 87º y 93º, con un promedio de 90,2º; el ángulo tibial entre 85º y 93º, con una media de 89,6º; y el ángulo femorotibial entre 177º y 182º con una media de 179,2º. La diferencia fue significativa para el ángulo femoral (p = 0,001), siendo muy significativa en el ángulo femorotibial (p < 0,001). Todos los casos pertenecientes al grupo con navegador mostraron un ángulo femorotibial considerado como ideal (180º ñ 3º), mientras que solo ocurrió en 9 de los pacientes intervenidos con la técnica estándar (p < 0,001). Conclusiones. La utilización de un sistema de navegación quirúrgica inalámbrico para la implantación de las prótesis de rodilla favorece la colocación del implante en una posición más cercana al eje mecánico ideal (AU)

Loosening of threaded acetabular cups in arthroplasty of the hip. The association with different types of coxarthrosis.

Seventy-nine patients underwent hip arthroplasty using a threaded acetabular cup during 1988 and 1989. Out of 71 cups implanted for coxarthrosis, radiographs of 62 have been reviewed at a mean follow up of 69 months. The survival rate at 5.5 years was 77.5%. The mean age at operation was 61 years. Loosening of the cup occurred in 7 cases with pain on walking; 5 had a revision operation. In another 28 patients, radiolucent lines greater than 1 mm were found around the cup and 7 of these were unstable. The previous coxarthrosis was classified as atrophic with 5 loose cups, normotrophic with 2 loose cups and hypertrophic with no loosening. This difference between loosening in the atrophic and hypertrophic types of preexisting coxarthrosis was statistically significant. Radiolucent lines were present in 61% of the atrophic cases, 53.4% of the normotrophic and 25% of the hypertrophic, which was also significant. If the cases of loosening are added to those with radiolucent lines, the types of coxarthrosis show highly significant differences. Threaded cups had a high percentage of failure which was greater in cases with atrophic coxarthrosis.

Patellar complications after total knee arthroplasty.

One hundred total knee arthroplasties implanted between 1989 and 1993 in 70 women and 30 men (average age 67.4 years) have been retrospectively reviewed. Six late patellar complications occurred: two fractures, two subluxations, one dislocation and one loosening. Four had a further operation. The patient's age, type of implant, lateral patellar release, thickness of the implant and the final range of movement were studied. Complications have been more common in men (8.7%) than women (5.2%) with a statistically significant difference (p < 0.05). This may be because men make a greater functional demand on their arthroplasties. No other factors were relevant.