Constrained acetabular liners in hip revision surgery. A low-cost solution for senile patients.

The objective of this study was to analyze the results of a cemented polyethylene model that captures the hip prosthetic head. In a retrospective study we reviewed 36 cemented constrained acetabular liners implanted in patients older than 75 years (mean 83, SD : 4.4), of which 30 patients were aged 80-90 years and 26 were women. The average period of follow-up of our patients was 25.4 months (12-39 months, SD : 7.3). In 26 patients this model was implanted due to recurrent dislocation or instability, in 8 other cases this model was implanted during revision surgery for periprosthetic fractures, aseptic loosening of the -acetabular component, wear of the polyethylene or replacement of the implant because of infection. There was a single case of recurrent dislocation (2.8%). Cemented acetabular constrained liners are a good option in revision surgery in senile patients in which the femoral stem is firmly fixed to the bone.

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.

Metal-on-metal surface hip arthroplasties. Is annual monitoring of blood metal levels necessary? / Artroplastias de superficie metal-metal en cadera. ¿Es necesario realizar seguimiento anual mediante determinación de metales en sangre?

INTRODUCTION: Blood cobalt (Co) and chromium (Cr) ion levels have been used as surveillance tools for adverse reaction to metal debris in metal-on-metal (MoM) hip arthroplasty. The aim of our study was to present serial 7-13 year blood Co and Cr levels in a cohort of MoM total hip arthroplasties in asymptomatic patients. MATERIAL AND METHODS: A total of 52 MoM surface total hip arthroplasties were included in this study with data collected prospectively. Annual follow-up with blood Co and Cr measurements was performed. Revision surgery was necessary for 16 patients and therefore they dropped out of the study. The metal ion levels were analyzed separately in 31 asymptomatic patients. RESULTS: High Cr or Co levels were not found continuously in any of the asymptomatic patients. The median Cr in blood was maintained between 1.3 and 5.4µg/L and that of Co between 0.5 and 1.2µg/L. After 7 years, there was no significant change in Co and Cr values. CONCLUSION: In the medium term and in asymptomatic patients, the metallic blood levels remained unchanged; therefore, it does not seem appropriate to repeat these tests on a permanent basis in annual controls.

Navigated versus conventional total knee arthroplasty: A prospective study at three years follow-up. / Artroplastia total de rodilla navegada versus convencional; estudio prospectivo a 3 años de seguimiento.

OBJECTIVE: Computer-assisted surgery application in total knee arthroplasty (TKA) has shown more accurate implant alignment compared with conventional instrumentation and is associated with more homogeneous alignment results. Although longer implant survival and superior clinical outcomes should be expected from navigated TKA, currently available evidence does not support this hypothesis. The aim of this study was to compare navigated TKA with conventional TKA regarding clinical and radiological outcomes after a 3-year follow-up under the hypothesis that navigated TKA would provide better outcomes than conventional TKA. MATERIAL AND METHOD: In a prospective multicentre study, 119 patients underwent navigated TKA and 80 patients received conventional instrumentation. Patients were evaluated at the baseline and at postoperative months 3, 12, 24, and 36. Analysis included the American Knee Society Score (KSS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Short Form-12 (SF12) Health Survey, and radiographic assessment. RESULTS: All clinical scores improved significantly for all patients during the follow-up but were significantly better in the navigation group. The percentage of patients showing a mechanical axis between 3° of varus and 3° of valgus was significantly higher in the ATR group (93%) than in the conventional TKA group (71%) (P<.01). CONCLUSIONS: The use of computer-assisted surgery in TKA provides more accurate mechanical alignment and superior short-term functional outcomes compared to conventional TKA.

Fever, Malaise, and Dyspnea in a Diabetic Heart Transplant Patient: A Case Report.

Patients with solid-organ transplants usually present at the emergency department with nonspecific symptoms. The physician should consider a great variety of syndromes and diseases, given the greater risk that solid-organ transplant patients carry because of immunosuppression and transplant-related conditions. Myocardial infarction caused by cardiac allograft vasculopathy must be always suspected and ruled out, even when initial symptoms do not orientate in that direction. We present a case that conjugates signs that can be present in different pathologies. It shows that fever is not always related to infection or rejection but could also appear in acute cardiac allograft vasculopathy. It emphasizes the need of a multi-disciplinary team led by a heart transplant specialist when dealing with this sort of clinical case.

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.

Behavior of the femoral stem in the Bihapro hip prosthesis.

This study evaluated the hydroxyapatite-coated femoral stem of the Bihapro hip prosthesis (Biomet Ltd, Bridgend, United Kingdom) using radiography, TC-99 scintigraphy, and bone densitometry. Thirty stems with >2 years of follow-up (mean: 31 months) were evaluated. No loosening or changes in the position of the implant were seen, and the mean subsidence was 2.2 mm. Radiography revealed a densification in the metaphyseal zone with reconstruction of the trabecular lines in 21 cases, while in 22 patients, radiolucent lines in the distal area of the femoral component were observed. Scintigraphy showed a diaphyseal normo-captation in 19 cases and a hypercaptation <1.4 with a mean index of 1.1 in 10 patients. Metaphyseal hypercaptation >1.4 was seen in 24 patients. Bone densitometry revealed increased density in the metaphyseal zones in 29 patients with a periprosthetic/normal bone quotient of 1.4.

[The risk of thromboembolism in prosthetic surgery of the hip, and its prevention by administration of individualized heparin dosages]. / Le risque thrombo-embolique et sa prévention en chirurgie prothétique de la hanche, par administration d'héparine en dose personalisée.

After hip replacement, thromboemboli remain a very frequent and severe complication. Different techniques of prevention have been described but there is no pharmacological method of definitively proving the effectiveness of such techniques. The use of low-dose heparin has been recommended, but owing to the variable results obtained in this type of surgery, certain authors prefer using an individualized dose. The authors report their experience with this regimen in 30 patients with certain individual thromboembolic risk factors who underwent hip arthroplasty. Despite these cases of deep vein thrombosis, no symptomatic pulmonary emboli were diagnosed. There were two patients with hematomas at the iliac crest which resolved without sequelae after drainage. The different rules to be followed for prevention of these complications are analyzed; the authors underscore the need for individual adaptation of the heparin dose.

Acetabular loosening in cemented arthroplasty of the hip. Relationship with atrophic arthrosis.

Between 1976 and 1982, 126 low friction arthroplasties were implanted in primary arthrosis of the hip. The displacement rate or acetabular loosening related to the type osteoblastic response to the disease were studied. The hips were subdivided into three groups based on the radiographical aspect observed prior to implant. The atrophic type revealed a greater incidence for this type of complication (27.3%) whereas cases classified as normotrophic revealed a 5.6% incidence and hypertrophic a 6.1% incidence. The authors conclude that the type of bone response in primary arthrosis plays an important role in the occurrence of acetabular mobilization, and that osteoblastic response may be considered to be of prognostic value together with other well-known factors in the evolution of this type arthroplasty.

[Vascular complications after pelvic rami fracture]. / Complicación vascular tras fractura de ramas pélvicas.

The case is presented of a 78 year-old patient who suffered a right ileo- and ischiopubic rami fracture after a casual fall. A few hours later, she presented with sudden abdominal pain and hypotension. Imaging test showed extraperitoneal hemorrhage with active bleeding and hemodynamic compromise. The progressive worsening, with anemia and hemodynamic instability, required her being sent to the reference hospital for selective embolization of the bleeding point. After embolization, the patient́s situation stabilized, and she was then able to sit down one week later. The fracture consolidated 3 months later. Although low-energy pelvic fractures by lateral compression do not usually present with complications, sometimes they require a strict control due to the potential risk of vascular injuries.

[Detection of metal ions in hair after metal-metal hip arthroplasty]. / Detección de iones metálicos en cabello tras artroplastia de cadera metal-metal.

OBJECTIVE: There is an increase in the levels of metals in the serum and urine after the implantation of some models of metal-metal hip prosthesis. It has recently been demonstrated that there is an association between these levels and the levels found in hair. The aim of this study is to determine the presence of metals in hair, and to find out whether these change over time or with the removal of the implant. MATERIAL AND METHOD: The levels of chromium, cobalt and molybdenum were determined in the hair of 45 patients at 3, 4, 5, and 6 years after a hip surface replacement. The mean age was 57.5 years, and two were female. Further surgery was required to remove the replacement and implant a new model with metal-polyethylene friction in 11 patients, 5 of them due to metallosis and a periarticular cyst. RESULTS: The mean levels of metals in hair were chromium 163.27 ppm, cobalt 61.98 ppm, and molybdenum 31.36 ppm, much higher than the levels found in the general population. A decrease in the levels of chromium (43.8%), molybdenum (51.1%), and cobalt (91.1%) was observed at one year in the patients who had further surgery to remove the prosthesis. CONCLUSIONS: High concentrations of metals in the hair are observed in hip replacements with metal-metal friction, which decrease when that implant is removed. The determination of metal ions in hair could be a good marker of the metal poisoning that occurs in these arthroplasty models.

[Does the medial-lateral stability of total knee replacements have an effect on short-term clinical outcomes? One-year results of a multicentre study with computer assisted surgery]. / Influye la estabilidad mediolateral de las artroplastias totales de rodilla en la evolución clínica a corto plazo? Estudio multicéntrico a un año con cirugía asistida por ordenador.

OBJECTIVE: To evaluate the influence of the medial-lateral stability of the joint on the short-term clinical outcomes after performing navigation in total knee replacement. MATERIAL AND METHODS: A multicentre prospective study was conducted on 111 consecutive total knee replacements performed with computer assisted surgery. The study included the evaluation of KSS, WOMAC, and SF-12 preoperatively, and at 3 and 12 months of follow-up, and correlation with stability data obtained during surgery, in extension and at 20° and 90° of flexion. RESULTS: No differences were found in WOMAC, KSS and SF-12 relative to coronal stability during surgery. CONCLUSIONS: Variations in coronal stability were shown to have no influence on the short-term clinical results of navigated total knee replacement.

[Minimally invasive surgery versus conventional surgery. A review of the scientific evidence]. / Cirugía de mínima invasión frente a cirugía convencional. Una aproximación desde la evidencia científica.

The concept that small incisions lead to a better outcome in many procedures has extended into most surgical areas, orthopaedic surgery among them. However, in some cases there is not enough scientific evidence to recommend these procedures. This article attempts to provide an updated review of the works published with sufficient scientific evidence on the advantages of minimally invasive surgery (MIS) compared to conventional access approaches. The published articles, meta-analyses and systematic literature reviews with level I or II evidence are reviewed in topographic order. Wherever possible, the information available on the costs-benefits of this type of surgery is also reviewed.

Navigation in total knee arthroplasty. A multicenter study.

We carried out a multicentre study to compare the postoperative femorotibial radiographic axis in two total knee replacement groups; one using manual instrumentation and the other using navigation. In the latter group, three navigation systems were used: Stryker, Orthopilot and Navitrack. The prior circumstances of patients in terms of age, weight, aetiology, epicondylar perimeter, patellar tendon length and knee deformity was similar in both groups. The duration of the operation was longer in the group with navigation (16.7 min). A normal femorotibial axis was more frequently obtained in the group with a navigator compared to the manual group (48.1% and 30%, respectively). A varus axis was most common in the manual group (42.2 and 26.9%, respectively). When we analysed the final postoperative radiographic axis, taking 180 degrees to be a normal result, we noted that cases where manual instrumentation was used deviated by 1.19 degrees more than those carried out with navigation, with this difference being statistically significant (P<0.001). No significant differences were found in the final angle of the extremity with the different navigation systems. The navigation systems used in this study improve the frontal angle of the arthroplasty.

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.

Mechanical failure in double cup arthroplasty of the hip.

Mechanical complications of double cup arthroplasty of the hip are common, particularly loosening of the components. This paper describes a series of 26 such operations with an average follow-up of 67 months. There was a failure rate or 53.8% and these hips had to be revised with another type of replacement. Our results are compared with other reported series.

Chondrosarcoma of the bones of the hand. Report of two cases.

Implantation of chondrosarcoma in the bones of the hands is an infrequent occurrence. We present two cases in which the fifth metacarpal and the proximal phalanx of the index finger, respectively, were affected in two patients aged 47 and 67 years, who, without previous known lesions, came to consultation on the appearance of pain and progressive local growth of tumour. After histological diagnosis we proceeded to disarticulation at the level of the affected bone. We review the literature on the appearance of this type of tumour in the hand.

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.