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Total hip arthroplasty revision is increasingly becoming a common procedure, but the acetabular bone loss and the advanced age of the patients make revision procedures extremely complex and technically demanding. The aim of the present work is to examine the clinical and radiological results of the Burch-Schneider anti-protrusio cage (APC) implanted in revision hip arthroplasty with severe acetabular bone deficiency in elderly people. Between February 1994 and November 2005, a total of 60 revision operations of acetabular components were performed in 60 select patients (42 females and 18 males), using the Burch-Schneider APC. The indication for the Burch-Schneider APC use was massive pelvic bone loss with migration of the prosthesis cup and high-grade acetabular defects (type III or IV AAOS). The mean age at the time of surgery was 82 years (range 78-85 years). Polymethylmetacrylate cement (PMMA) was used to fill bony deficiencies in all the procedures. No graft was used. The average Harris Hip Score had improved from 28.2 preoperatively to 82.5 points at the time of follow-up. According to the classification of Gill et al., we have seen no Burch-Schneider cages definitely loose or probably. Only one acetabular component has been revised (for recurrent dislocation). Acetabular reconstruction with the use of cement and an acetabular support ring appears to have a useful role in the treatment of severe acetabular bony deficiency in elderly patients and may provide a definitive reconstruction.

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Impulsiveness is multifactorial in nature; hence, to investigate its components diverse theoretical models supported by different measurement tools have been proposed. Attention has been particularly focused on the effects that impulsiveness can have in determining and/or maintaining a behaviour of dependence. In the present study a group of subjects with alcohol dependence in treatment (N = 20) were compared with a control group (N = 21); the two groups were administered three different instruments designed to investigate the dimension of impulsiveness. A significant difference was found concerning the performance on the Iowa Gambling Task. This is a test that simulates a gambling situation and so evaluates the capacity to discern, in a decisional task, advantageous vs. non-advantageous options, where the former permit an immediate modest gain but also a future modest loss while the latter carry a heavier penalty than they allow to gain, even if the gains are very big. The alcoholics persisted in making impulsive choices significantly more than the control group, preferrng thus the higher wins but risking also greater losses. This result, in line with what is reported by the present contributions on the decisional style of subjects characterized by drug abuse, may be important in understanding the factors that predispose to and maintain excessive drinking behaviour.

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A computer-based pre- and post-operative analysis of total hip replacement (THR) is presented. The analysis was performed by using and innovative combination of X-ray measurements and gait analysis. The several important biomechanical factors that affect effective THR are analysed in a test clinical case of conversion of hip fusion into THR. Geometrical positioning of the artificial joint should restore correct motion and adequate leverage of the surrounding muscles in order to exert the appropriate functional joint moments. Hip joint centre positioning pre- and post-operation was evaluated using a computer-based X-ray measurement tool. This enabled the calculation of the medio-lateral and proximal-distal off-set of the joint centre, the lever arms of the abductor muscles and the limb length discrepancy. Pre- and post-operative function was also evaluated using gait analysis, including joint kinematics, kinetics and electromyography. The whole analysis suggests that a good restoration of joint motion, a regression of pelvic compensation and a phasic activity of gluteus medius occur only when a good positioning of the prosthetic hip joint is obtained. This study proved a fundamental role played by these two computer-based tools in the support of the clinical decision making process.

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From May 1993 to January 1997, a total of 130 humeral fractures and nonunions were treated using an "elastic" unreamed nail. The elastic nail consists of a cylindrical proximal component tapered for the application of the impactor-extractor, distally containing the proximal ends of four or five secondary nails preloaded to diverge and held together by a retaining system. The surgical approach is through the olecranic fossa apex. Once introduced, the proximal end of the nail locks automatically by diverging the secondary nails in the proximal humeral epiphysis. Distally, the elastic nail is locked with a crossbolt. The elastic nail enables stable fixation of fractures or nonunions and allows early rehabilitation.

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The aim of the present paper was to evaluate the effectiveness of a sitting system based on the application of magnetic fields in the prevention of posture-related musculoskeletal disorders. We studied 5 healthy male volunteers during laboratory simulation tests including 60-minute sessions of "driving" and computer-work. Two subjects performed a 60-minute driving test on an isotonic dynamometer with a steering wheel, in which they had to steer for 2 min and drive normally for 3 min, alternatively. They repeated the test with and without the magnet-based sitting system. Three subjects performed a 60-minute computer-work test in a seated position with and without the magnet-based sitting system. EMG activity was registered in the trapezius muscles and at L1 and L5 lumbar level bilaterally with surface electrodes. The EMG trapezius activity continuously recorded was analysed with the APDF method, as proposed by Jonsson. Before and after the tests, the subjects performed a 60-sec isometric back extension at 60% MVC with a specific back dynamometer, while paraspinal EMG was recorded. The slope of decay of the median frequency of the EMG power spectrum was then calculated as an index of localised muscle fatigue. The results showed a decreased myoelectric activity both at shoulder and lumbar level by using the magnet-based sitting system for prolonged seated work tasks. Thus, the system appears to be an effective tool in preventing muscle contractures secondary to prolonged, constrained positions.

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The authors describe two cases of subacute epiphysiolysis with severe slipping submitted to corrective subcapitate osteotomy of the femur with an anterior approach. The patients were followed-up after approximately 7 years, and satisfactory results were observed: movement in flexo-extension was preserved with mild limitation of intrarotation. The accuracy of the osteotomy during surgery is emphasized in order to avoid necrosis of the femoral head, and hypercorrection in valgus to avoid shortening.

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The authors reviewed 61 cases of cervico-brachialgia due to posterolateral disc herniation treated at the Rizzoli Orthopaedic Institute between 1975 and 1985. Results were positive in 69.3% of the cases, partially negative or negative in 30.7%. An analysis of the results reveals a high correspondence between clinical diagnosis and surgical findings (82%): but the percentage of error in clinical diagnosis (18%) cannot be overlooked. For this reason the clinical diagnosis must be confirmed by CT and/or MRI. In our experience, the posterior approach has proven to be suited to resolving most cervico-brachial pain syndromes due to posterolateral disc herniation.

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The authors analyse the results of 23 cases of high tibial osteotomy for genu recurvatum in adults performed at the Rizzoli Orthopaedic Institute from 1968 to 1983. The osteotomy is at the supratuberosity level. After detaching the patella tendon an anterior bone wedge is inserted and the tendon reinserted at a higher level. This operation has produced better results than other surgical techniques. It is indicated in the osseous type of recurvatum or in the combined type in which the osseous component is predominant. In the combined type with a capsulo-ligamentous prevalence, the poor results obtained with osteotomy alone indicate the need for combining the operation with a plastic reconstruction of the posterior capsulo-ligamentous structures.

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The angle of anteversion, assessed by the Dunlap technique, was determined in 30 patients suffering from primary osteoarthritis of the hip. This was compared with the same angle in 10 normal subjects. The patients with arthritis showed a statistically significant increase in the angle. This is considered by the authors to play a significant part in the pathogenesis of primary osteoarthritis of the hip.

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In adult patients with considerable loss of function due to an unreduced congenital dislocation of the hip with a false acetabulum, the authors posed the question "Is it feasible, with a reasonable chance of success, to perform an arthroprosthesis in the "pathological" position, using the false acetabulum as a seating for the cup?" The aim of this study was to assess, in particular, the holding properties of the cup which has to be fitted after appropriate reaming, into this rather precarious false acetabulum. They define the indications for this procedure and describe their technique. The results of 34 operations, followed up for an average of 5 years, confirm the validity of this procedure.

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Decompensated arthrosis secondary to genu varum is always a severely disabling condition. In English speaking countries there is an increasing trend towards prosthetic replacement surgery, but the present paper aims to show that valgising tibial osteotomy is still a valid form of treatment. The authors also discuss the various techniques that have been used and describe the advantages and results of their own preferred technique of "domed" osteotomy.

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This study is an evaluation of intertrochanteric osteotomy in cases of idiopathic osteonecrosis of the femoral head (I.O.F.H.) in patients too young to be suitable for prosthetic replacement. The variety of material, the length of follow-up, and the detailed evaluation on a points system, are sufficient for valid comparison with more recently introduced methods of treatment.

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There are obvious advantages in intramedullary osteosynthesis by closed reduction as compared with open reduction and osteosynthesis using a plate and screws in non-articular fractures of the long bones. This has led to a modification of Küntscher's nail with a view to improving its effectiveness and enlarging the indications.

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