Introduction and purpose: The aim of this study is to determine whether a porous tantallium implant is effective in the treatment of femoral head osteonecrosis (ON) in its early stages.

Materials and methods: Between December 2002 and March 2006, 20 tantalum-on-rod screws were implanted in 15 patients with femoral head ON. A retrospective study was performed to analyze distribution by sample age, sex and etiology, stage of ON according to the Ficat and Arlet classification and the Shimuzu et al classification as modified by Lieberman et al. The result obtained was quantified according to subjective clinical evolution, ON evolution as determined by x-rays and the subsequent need for total hip replacement.

Results: Good results were obtained, with clinical remission and absence of necrosis progression in 60% of ON cases. Conversion to total hip replacement was necessary in 35% of hips. Mean follow-up was 16.4 months.

Conclusions: The treatment of ON with porous tantallium implants is quick and simple. It is important to use an accurate technique with implantation at the appropriate level and limit this surgery to the initial stages of the disease. To obtain more significant results it is necessary to study more cases and carry out a longer follow-up.

Introduction: For the health-care system and for society in general, fractures of the femoral neck are epidemic among the elderly. With increased life expectancy, this type of pathology will continue increasing in the future. The study of possible biological causes of this phenomenon will provide better understanding of the pathology and help us prevent such fractures. Different genes involved in the synthesis of nitric oxide and interleukins are related to the occurrence of fractures of the femoral neck.

Materials and methods: We studied 111 patients with fractures of the femoral neck between 2002 and 2004 and a control group of 127 patients operated on for total hip or knee replacement in the same period. In both groups we looked at different genetic polymorphisms of IL-1 alpha, IL-1 beta, IL-1 RA, NOS2 and NOS3. We also measured the levels of IL-1 beta, IL-6 and TNF alpha in patient sera.

Results: We found a significant difference for certain genetic polymorphisms related to IL-1 beta and NOS3 and patients with fractures of the femoral neck.

Conclusions: There are different genes related to inflammatory reactants which are significantly related to the presence of fractures of the femoral neck.

Purpose: Vascular complications in lumbar disc surgery are rare, difficult to diagnose and may have serious consequences. We review our experience in eight cases treated in the past 30 years.

Methods: Between 1976 and 2005 we operated on 16,391 cases of vascular pathology, eight for vascular complications after lumbar discectomy (herniated disc), six men and two women aged 36 to 70 (mean 52 years). The symptoms were abdominal pain in four, ischial irradiation in one, episodes of heart failure in one, limb oedema in two, acute haemorrhage in three, abdominal murmur in two. The diagnosis was made during surgery in two cases and immediately postoperative in the third due to severe hypovolemia. The others were diagnosed because of abdominal murmur, limb oedema and suspected abdominal aneurism. Abdominal CT scans and arteriography were performed in five cases. Treatment was surgical, with direct closure in seven cases and interposition of a Dacron aortoiliac prosthesis in the other. No sequelae were seen during follow-up, which lasted a maximum of fifteen years. All the patients returned to normal life and there was no mortality.

Conclusions: Because of the severity and rareness of this complication, few cases have been described in the literature, and its real incidence is therefore unknown. We should think of it whenever there is any unexplained, sustained haemodynamic disorder during lumbar disc surgery or immediately postoperative. Treatment should be immediate.

Introduction.- Some of the recommended alternatives to increase the cementless acetabular cups stability are the plasma sprayed porous coated and HA and the press-fit impaction. The incorporation of three peripheral fins improves final fixation avoiding micromotion at the immediate post operative period. From 1992 we have implanted 4068 cups, the majority of them in primary cases (78%). The rest 22% in revision cases.

Cup characteristics: hemispheric with fins to improve prumary fixation and HA coating; ring-long ystem in common with other Biomet models, reason why liner are interchangeables.

Material and methods.- 4.068 Bihapro cups (Biomet-Merck) were implanted at a multicenter study in three Hospitals, adjoined to the University, between 1992 and 2003. This is a press-fit model with a porous surface coated with HA and three peripheral fins to improve primary fixation and also dome holes to allow the use ob bone screws.

Prymary indication: osteoarthritis (76%), AVN (7%), fractures (8%), dysplasias (3%), rheumatoid arthritis (6%). Surgical approach: lateral (49%), posterolateral (34,2%), anterior (16,8%). Prophylaxis: antitrombotic (LMWH), antibiotic (1st generation cephalosporins), heterotopic ossification (indomethacin).

Results.- Results. 24 patients showed dislocation and 47 % had some degree of periarticular ossification one year alter surgery; the approach used did not show significative differences. The survival study was done using Kaplan-Meier’s curve. The end-point for failure in this study was the need to perform aesptic revision surgery; being the survival at 9 years of 99.49 % (CI 95 % 99.08 – 99.90). Seven cases needed revision surgery (0.3 %); two cases for migration of the cup and five cases for iterative dislocations.

Conclusions.- Acetabular cups with Plasma Spray Porous Coating in combination with HA, results stable at mid term. The supplementary fixation of the three peripheral fins avoids micromotion optimizing long-term fixation.

Aims: Hydroxyapatite HA-coated hip replacements were introduced in the late 1980ñs when the intermediate term results of porous-coated hip replacements were not proving to be satisfactory with a high rate of thigh pain even well þxed implants. The aim of our retrospective study was to review the results of group of patients who underwent HA-coated cup between 1992 and 2001, and evaluate the clinical and radiological outcome of the HA-coated cup over a 7 to 10 year period. Methods: In a multicenter study between 1992 and 2001 were used 2899 Bihapro cups (Biomet-Merck). This is a press-þt model with a porous surface coated with hydroxyl-apatite and three peripheral þns to improve primary þxation and also dome holes to allow the use of bone screws. In 993 (34.2%) cases a posterior approach was performed, lateral approach in 1419 (49%) and the anterior approach in 487 (16.8%) cases. All patients were mobilised on the second post-operative day once drains had been removed. They were encouraged to use crutches while walking for the þrst 6 weeks. Results: 35 patients (1.2%) showed dislocation. 47% of the seires had some degree of periarticular ossiþcation one year after surgery; the approach used did not show signiþ-cative differences. The survival study was done using Kaplan-Meierñs score. The end point for failure in this study was the need to perform aseptic revision surgery; being the survival at 9 years of 99.49% (CI 95%: 99.08 Ð 99.90).Conclusions: The acetabular shells with plasma spray porous coating in combination with HA results stable at mid term. The supplementary þxation of the three peripheral þns avoids micromotion optimizing lon-term þxation.

Introduction and Objectives: Though not a common disease, proximal femoral epiphysiolysis (PFE) is one cause of premature degeneration of the joint. The aetio-pathogenesis is unknown. The challenge with this disorder is making an early diagnosis. This study presents the experience of our center in surgical treatment of this condition.

Materials and Methods: This is a retrospective study of 27 cases of PFE in 25 patients treated between 1990 and 1998, analyzing therapeutic management at the time of presentation and clinical, radiographic, and subjective findings in the short and medium terms. Based on duration of symptoms, the disorder is classified as acute, chronic, or subacute. Degree of displacement is classified as mild (less than 30%), moderate (30–60%), and severe (great than 60%). Dunn and Angel’s criteria were used for clinical evaluation, as modified for this study. Radiographic follow-up was based on the capitodiaphyseal Southwick angle, measuring the amount of correction postoperatively and in the medium-term examination.

Results: There were 17 males (63%) and 10 females (37%). Average age was 12.5 years. The right side was affected in 10 cases (40%), the left in 13 (52%), and both sides in 2 (8%). The majority of patients presented with chronic epiphysiolysis (44%) with mild displacement (74%). In most cases, surgical intervention consisted of in situ fixation with or without a previous attempt at reduction, based on the degree of displacement on an orthopaedic table with scope guidance. Fixations were performed primarily with Kirschner wire or cannulated screws. Preoperative complications included incomplete reduction of the fracture, breakage of the Kirschner wire, and superficial infection of the surgical wound.

Discussion and Conclusions: The worst results were seen in patients with epiphysiolysis with severe initial displacement and in patients who developed aseptic necrosis of the femoral head or chondrolysis. Intra-articular penetration with this material and valgus positioning should be avoided. At present, we are doing the fixation of the epiphysis using a single cannulated screw. We believe early detection of the process is very important in cases featuring gradual displacement.