Prognosis of the contralateral hip after primary total hip replacement: Can it be predicted? / ¿Se puede predecir el pronóstico de la cadera contralateral tras una artroplastia total de cadera?

INTRODUCTION: Coxarthrosis is one of the most frequent and disabling pathologies. 20% of individuals over 60 years of age will develop symptomatic coxarthrosis and 10% of them will need a hip replacement; it is probably one of the orthopaedic procedures that most increases quality of life. When we recommend arthroplasty in clinical practice, patients often ask about the prognosis of their other hip. Will it deteriorate in the same way? Will it be necessary to replace it? When? The aim of the study is to determine if there is any variable or radiological sign that predicts the medium-term prognosis of the contralateral hip after total hip arthroplasty. MATERIAL AND METHODS: A retrospective review of patients who underwent total hip arthroplasty in our hospital during 2011 and 2012 was carried out, with a total of 543 patients. The coxarthrosis degree at X-ray was determined at the time of the first arthroplasty and at regular intervals during follow-up, according to the JOA and Tönnis classifications, analyzing each of the items included in these classifications. Its relation with the progression of osteoarthritis and the need of contralateral hip replacement was established. RESULTS AND CONCLUSIONS: A progression of osteoarthritis of the contralateral hip could be expected in the next 3 years in 10% of patients. This progression will be greater and faster in those with JOA grade III-IV/Tönnis grade II-III, especially, in those with greater joint narrowing and femoral head shape score, and can reach between 25 and 30% of patients. The initial JOA/Tönnis degree is a predictive factor for requiring a hip replacement on the contralateral side.

[Translated article] Prognosis of the contralateral hip after primary total hip replacement: Can it be predicted?

INTRODUCTION: Coxarthrosis is one of the most frequent and disabling pathologies. 20% of individuals over 60 years of age will develop symptomatic coxarthrosis and 10% of them will need a hip replacement; it is probably one of the orthopaedic procedures that most increases quality of life. When we recommend arthroplasty in clinical practice, patients often ask about the prognosis of their other hip. Will it deteriorate in the same way? Will it be necessary to replace it? When? The aim of the study is to determine if there is any variable or radiological sign that predicts the medium-term prognosis of the contralateral hip after total hip arthroplasty. MATERIAL AND METHODS: A retrospective review of patients who underwent total hip arthroplasty in our hospital during 2011 and 2012 was carried out, with a total of 543 patients. The coxarthrosis degree at X-ray was determined at the time of the first arthroplasty and at regular intervals during follow-up, according to the JOA and Tönnis classifications, analyzing each of the items included in these classifications. Its relation with the progression of osteoarthritis and the need of contralateral hip replacement was established. RESULTS AND CONCLUSIONS: A progression of osteoarthritis of the contralateral hip could be expected in the next 3 years in 10% of patients. This progression will be greater and faster in those with JOA grade III-IV/Tönnis grade II-III, especially, in those with greater joint narrowing and femoral head shape score, and can reach between 25 and 30% of patients. The initial JOA/Tönnis degree is a predictive factor for requiring a hip replacement on the contralateral side.

Computer-assisted navigation in total knee arthroplasty without femoral hardware removal.

PURPOSE OF THE STUDY: The use of navigation applied to total knee arthroplasty in knees with femoral hardware retained has not been studied. MATERIAL AND METHODS: We use navigation in six patients to implant a total knee arthroplasty while retaining the femoral hardware. The retained materials were screws in two cases, diaphyseal plates in another two, intramedullary nails in one and supracondylar tube/plate in another one. Preoperative knee scores were within the 46-66 range, whereas the functional scores were within 40-68. The coronal deformity varied between 30° varus and 5° valgus. RESULTS: The final femoral mechanical axis was between 2° valgus and 3° varus; the axis of the limb was between 4° valgus and 3° varus. Knee scores improved in all cases, with scores between 75 and 90 points (p = 0.028); functional scores were between 64 and 90 points (p = 0.043).The final range of mobility was within the 70°-110° range, with a slight improvement over the preoperative status (p = 0.042). No complications have arisen throughout the follow-up (mean 16 months). CONCLUSIONS: The use of navigation constitutes a good option in the treatment with total arthroplasties for patients with femoral hardware retained.

Frontal alignment in total knee arthroplasty. Comparative study between radiographic measurement and surgical navigation. / Alineación frontal en la artroplastia total de rodilla. Estudio comparativo entre medición radiográfica y con navegación quirúrgica.

OBJECTIVE: To establish the concordance between angulation of the femoro-tibial mechanical axis measured with x-rays and surgical navigation in both the pre and postoperative period after a total knee arthroplasty (TKA) was implanted. MATERIAL AND METHOD: Pre and postoperative measurements were analyzed in 88 TKA of the same model and all performed with the same surgical navigation system. The mechanical frontal angle (MFA) and femoro-tibial anatomic angle were measured before and after the TKA. The angulation was digitally measured with a teleradiography. In the navigation, the femoro-tibial angle at rest, forced varus and valgus were registered and the average of these three measurements was calculated. RESULTS: The mean preoperative MFA measured on the radiograph was 4.55°. The mean of the same angle measured on the postoperative radiograph was 1.72°, (p=0.05). The mean of the MFA measured with navigation before TKA was 3.12° and after the implant with navigation was 0.53 (P=.013). The concordance coefficient between the MFA in teleradiography and in navigation was 0.869 (P<.001) preoperatively and 0.709 postoperatively (P=.017). CONCLUSIONS: We found a strong concordance between radiographic and surgical navigation measurements of the MFA. This may imply that teleradiography is not necessary when using surgical navigation in TKA.

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).

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.

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.