Introduction. Primary stability of the Burch-Schneider ring (BSR) in case of acetabular revision is discussed controversial. In a retrospective two centre cohort study we analyzed the influence of the mode of screw fixation and the restoration of the center of rotation on migration, loosening and other radiographic parameters. Material/Methods. Patients with a minimal radiographical follow-up of 2 years and suitable for EBRA analysis were included. In group 1 (46 patients) screws were placed through the cranial spherical part of the ring and covered by cement and cup, in group 2 (40 patients) screws were placed through the cranial flange. Preoperative bone defects were classified, the postoperative centre of rotation was determined. Changes of screws were recorded, migration exceeding >1mm was seen as significant. Results. Demographic data and size of bone defect were comparable in both groups. No cups in group 1 and in group 2 were re-revised. In group 1 the centre of rotation was medialized mean 5.5 (SD 8.2) mm, in group 2 it was lateralised mean 11.0 (SD 10.3) mm (p<.001). Screw changes were observed in 5 (10.9%) patients in group 1 and 14 (35%) patients in group 2 (p=.009). Migration at 2 years was observed for 17 (37%) patients in group 1, mean migration was 1.0 (SD 1.0) mm. In group 2 21 (52.5%) patients showed migration at 2 years (p=.193), mean migration was 1.6 (SD 1.7) mm (p=.031). Conclusion. Medialization of the implant and screw fixation with compression of the ring against the acetabular roof reduces migration and screw changes. The improved stability might be due to better osteointegration of the BSR and angular stability of the screws which are additionally fixed with cement

Introduction. Current artificial discs include 1 or 2 bearing surfaces, providing 3 or 5 degrees of freedom. The ESP® is a one-piece e implant made of silicon and polycarbonate -urethane securely fixed to titanium endplates. It allows limited rotation and translation with elastic return. This cushion without fixed rotation center achieves 6 degrees of freedom including shock absorption. This objective of this study was to evaluate the safety and efficacy of the concept in a prospective nonrandomized trial. Material and methods. Prior to clinical implantations, the device was endurance tested at least 40 millions cycles. The polymer core weight and properties, the geometrical characteristics and cohesion of the implants remained stable. A prospective trial was initiated in 2004 for L3L4, L4L5 and L5S1 levels. Total disc replacements have been performed in 153 lumbar levels through extra-peritoneal mini-invasive anterior approach with a minimum 2 years follow-up. Results. There was no clinical or radiological device related complication, except 2 early revisions for post-traumatic implant migrations (8, 17 days post-op.). When comparing the device to other implants, clinically relevant improvements in VAS, SF-36 and ODI scores were observed. At ultimate follow-up, the index level was mobile in 83% of the cases (5,3 ° ± 4.1). The mean centre of rotation was in the physiological area in 78% of cases without relevant modification of adjacent disc levels (Spineview® analysis). Conclusion. The 6 years clinical follow-up demonstrate the reliability of the concept and the safety and forgiveness of the implant

Introduction. Reverse shoulder replacement is a surgical option for cuff tear arthropathy. However scapular notching is a concern. Newer designs of glenospheres are available to reduce scapular notching. Eccentric glenosphere with a lowered centre of rotation have been shown to improve range of adduction in vitro. We hypothesize that the eccentric glenosphere improve clinical outcomes and reduce scapular notching. Method. This is an ongoing randomized controlled double blind prospective clinical trial. Patients 70 years or older at North Shore hospital who have a diagnosis of cuff tear arthropathy and require surgery were consented for this study. Patients were allocated a concentric or eccentric 36 mm glenosphere intraoperatively, using a computer generated randomization contained in a sealed envelope. The surgical technique and post operative rehabilitation were standardized. Patients were followed up by a research nurse and postoperative radiographs were also taken at regular intervals. Clinical assessment include a visual analogue pain score, subjective shoulder rating, American Shoulder and Elbow Society Score, and Oxford shoulder score. Complications were checked for and radiographs were assessed for scapular notching. Results. There were 23 patients in the concentric and 24 patients in the eccentric glenosphere group. Average age and duration of follow up were comparable. There was no statistical significant difference but there was a trend towards better functional outcome and better range of motion in the eccentric glenosphere group. There was no scapular notching in the eccentric and three cases of scapular notching in the concentric glenosphere group. Conclusions. Reverse shoulder replacement significantly improve pain, function and range of motion in patients with cuff tear arthropathy. Eccentric glenosphere prevents scapular notching in the SMR reverse prosthesis

Objectives. The additive use of an external modular device may improve dorsal compression forces in pelvic external fixation. This would improve the efficiency of indirect reduction and stabilization with an anterior pelvic external fixator. The purpose of this study was to determine the forces of the posterior pelvis achieved by a new device improving the application of a supraacetabular anterior external fixator compared with other constructs. Material and Method. Synthetic pelvic models were used. Complete pelvic ring instability was created by symphyseal and unilateral sacroiliac joint disruption. Four different constructs of fixation were tested. A pressure-sensitive film was placed in the sacroiliac joint. The constructs were applied in a standardized way. The maximum sacroiliacal compression loads (N) of each trial was recorded. Statistics was performed with the student t-test. Results. Standard supraacetabular two-pin external fixator achieved a dorsal compression load of 13.84 (SD 8.13). The new dorsal pelvic compression device delivered 177.05N (SD 32.32) of load across the sacroiliac joint when the pins were inserted half way and 183.58N (SD 46.64) with full pin insertion. Both the half- and full-pin construct demonstrated a significant dorsal load improvement with the pelvic compressor (p<0.05) compared with the standard supraacetabular fixator group. The C-clamp revealed compression forces of 384.88N (SD 22.95), which was significantly greater than all the other groups (p<0.05). Conclusion. We tested a simple and new modular device for improved application of pelvic external fixation. The centres of rotation of supra-acetabular pins were determined and used to achieve greater dorsal compression forces in disrupted pelvic ring injuries. The compression load is less than with a C-Clamp, but significantly greater than the familiar technique of standard external supra-acetabular fixation. This improves the initial stability in acute management of unstable, disrupted and life threatening pelvic ring fractures

INTRODUCTION. Limb salvage surgery is a common treatment for patients who suffer from bone tumors. In the case of pelvic tumors this creates a challenge for the surgeon and the treatment remains controversial because the oncologic complications like local recurrence, dissemination and orthopaedic ones, like infection, haemorrhage, and mechanical problems of reconstructions Tumors affecting the acetabulum are a challenge for the surgeon because of the impact in the function of the extremity. There are many reconstruction techniques described in the literature like prosthesis, allograft systems, arthrodesis, etc…, but still there is not a gold standard due to the poor functional results at long term follow up, and the associated complications of all techniques. In this study we show the experience in our center on pelvic reconstructions after tumors affecting the acetabulum area (zone II). MATERIAL AND METHODS. We surgically treated 81 pelvic tumors from 1997 to 2009 following the Enneking and Dunham calssification attending to the localization of the tumor: Zone I 38 (iliac bone)Zone II 25 (acetabulum)Zone III 18 (pelvic branches)In zone II tumors we performed pelvic reconstruction in eight cases, with different type of prosthesis. In 5 cases we performed saddle prosthesis (group A) and in 3 cases we performed Coned-Stanmore Implants type prosthesis with sacro-iliac anchorage. The mean follow up of the serie was 3,5 years (1–6 years). In group A the mean follow up was 5 years and in group A and in group B the mean follow up was 1 year due to the recent implantation in our center of Coned type prosthesis for pelvic reconstruction. We evaluated our results with these two types of prosthesis. RESULTS. Oncologic: group A we had a local recurrence of 25% and 25% of the patients died. group B we had no cases of local or systemic recurrence and we didn't registered any death. Functional: In group A the patients showed local pain and difficulty to walk probably due to the change of the center of rotation of the hip and instability of the saddle prosthesis. In group B all patient's followed physical therapy programs without problems and were able to walk with crutches ten months after surgery. Complications:group A we had a 25% of perioperative infection and a 25% of dislocation of the prosthesis. In group B we did not have any of these complications. CONCLUSIONS. Saddle prosthesis mantain the length of the extremity and allow weight bearing but they do not give a good stability. Even if we only have one year follow up with this Coned prosthesis with sacro iliac anchorage we achieved much better functional results and a lower rate of complications

Aims

To evaluate the outcomes of cemented total hip arthroplasty (THA) following a fracture of the acetabulum, with evaluation of risk factors and comparison with a patient group with no history of fracture.

We used an inverted shoulder arthroplasty in 43 consecutive patients with a mean age of 78 years (65 to 97) who had sustained a three- or four-part fracture of the upper humerus. All except two were reviewed with a mean follow-up of 22 months (6 to 58).

The clinical outcome was satisfactory with a mean active anterior elevation of 97° (35° to 160°) and a mean active external rotation in abduction of 30° (0° to 80°). The mean Constant and the mean modified Constant scores were respectively 44 (16 to 69) and 66% (25% to 97%). Complications included three patients with reflex sympathetic dystrophy, five with neurological complications, most of which resolved, and one with an anterior dislocation. Radiography showed peri-prosthetic calcification in 36 patients (90%), displacement of the tuberosities in 19 (53%) and a scapular notch in ten (25%). Compared with conventional hemiarthroplasty, satisfactory mobility was obtained despite frequent migration of the tuberosities. However, long-term results are required before reverse shoulder arthroplasty can be recommended as a routine procedure in complex fractures of the upper humerus in the elderly.

The purpose of this study was to assess the stability of a developmental pelvic reconstruction system which extends the concept of triangular osteosynthesis with fixation anterior to the lumbosacral pivot point. An unstable Tile type-C fracture, associated with a sacral transforaminal fracture, was created in synthetic pelves. The new concept was compared with three other constructs, including bilateral iliosacral screws, a tension band plate and a combined plate with screws. The pubic symphysis was plated in all cases. The pelvic ring was loaded to simulate single-stance posture in a cyclical manner until failure, defined as a displacement of 2 mm or 2°. The screws were the weakest construct, failing with a load of 50 N after 400 cycles, with maximal translation in the craniocaudal axis of 12 mm. A tension band plate resisted greater load but failure occurred at 100 N, with maximal rotational displacement around the mediolateral axis of 2.3°.

The combination of a plate and screws led to an improvement in stability at the 100 N load level, but rotational failure still occurred around the mediolateral axis. The pelvic reconstruction system was the most stable construct, with a maximal displacement of 2.1° of rotation around the mediolateral axis at a load of 500 N.

This randomised study compared outcomes in patients with displaced fractures of the clavicle treated by open reduction and fixation by a reconstruction plate which was placed either superiorly or three-dimensionally. Between 2003 and 2006, 133 consecutive patients with a mean age of 44.2 years (18 to 60) with displaced midshaft fractures of the clavicle were allocated randomly to a three-dimensional (3D) (67 patients) or superior group (66). Outcome measures included the peri-operative outcome index, delayed union, revision surgery and symptoms beyond 16 weeks. CT was used to reconstruct an image of each affected clavicle and Photoshop 7.0 software employed to calculate the percentage of the clavicular cortical area in the sagittal plane. The patients were reviewed clinically and radiographically at four and 12 months after the operation. The superior plate group had a higher rate of delayed union and had more symptomatic patients than the 3D group (p < 0.05). The percentage comparisons of cortical bone area showed that cortical bone in the superior distal segment is thicker than in the inferior segment, it is also thicker in the anterior mid-section than in the posterior (p < 0.05).

If fixation of midshaft fractures of the clavicle with a plate is indicated, a 3D reconstruction plate is better than one placed superiorly, because it is consistent with the stress distribution and shape of the clavicle.