Latarjet procedure (transfer of coracoid process to the anterior glenoid rim) has been widely used for severe anterior shoulder instability. The purpose of the present study was to investigate the intraarticular stress distribution after this procedure to clarify the pathomechanism of its postoperative complications. CT-DICOM data of the contralateral healthy shoulder in 10 patients with unilateral anterior shoulder instability (9 males and 1 female, age: 17–49) was used for the present study. Three-dimensional finite element models of the glenohumeral joint was developed using software, Mechanical Finder (RCCM, Japan). In each shoulder, a 25% bony defect was created in the anterior glenoid cavity, where coracoid process was transferred using two half-threaded screws. The arm position was determined as 0-degree and 90-degree abduction. While medial margin of the scapula was completely constrained, a standard compressive load (50 N) toward the centre of the glenoid was applied to the lateral wall of the greater tuberosity. A tensile load (20N) was also applied to the tip of coracoid process along the direction of conjoint tendon. Then, elastic analysis was performed, and the distribution pattern of Drucker-Prager equivalent stress was investigated in each model. The proximal half of the coracoid represented significantly lower equivalent stress than the distal half (p < 0.05). In particular, the lowest mean equivalent stress was seen in its proximal-medial-superficial part. On the other hand, a high stress concentration newly appeared in the antero-inferior aspect of the humeral head exactly on the site of coracoid bone graft. We assumed that the reduction of mean equivalent stress in the proximal half of the coracoid was caused by the stress shielding, which may constitute one of the pathogenetic factors of its osteolysis. A high stress concentration in the humeral head may eventually lead shoulder joint to osteoarthritis.

Purpose of the study: These fractures, and the patients, are generally unstable. Mortality associated with these fractures remains high. It is mainly due to the haemorrhagic risk of the presacral venous plexus and the iliac system. Different techniques have been described to control the haemorrhage: pelvic girdle, embolisation, ligature of the iliac arteries, pelvic packing, pelvis clamp or external fixator. Our objective was to analyse our series of fractures of this type in order to optimise patient outcome.

Material and methods: A prospective study was undertaken from January 2003 to December 2006. Among 450 multiple injury patients, 68 presented an unstable fracture of the pelvis, type B or C. The 38 patients included in this series were haemodynamically unstable. The mean ISS for these patients was 53, mean age 38.6 years (range 24–51). Fractures were diagnosed on plain x-rays of the pelvis, ap view, completed by a total body scan.

Results: All patients were victims of high-energy traffic accidents and were managed using the ATLS protocol. Five patients died early despite intensive care. The patients were divided into three groups: group X: 19 patients treated with a first-intention external fixator, with or without arteriography, 18 patients survived, 94%; group Y: 8 patients treated with a first-intention external fixator with arteriography and followed by laparotomy, 7 patients survived, 87%; group Z: 6 patients had laparotomy without an external fixator, 6 patients died, 100% mortality.

Conclusion: In our experience, the best way to control bleeding associated with unstable fractures of the pelvis is as follows: pelvic girdle at the scene of the accident to the emergency room, emergency external fixation followed by laparotomy if the ultrasound is positive. False positives occur due to suffusion of the retroperitoneal haematoma. Emergency laparotomy without prior external fixation of the pelvis lead to 100% mortality in our series. Similarly pelvic packing or the retroperitoneal approach cannot be proposed without exploration.

Purpose: We aimed to provide an anatomical basis for surgical techniques in rotator cuff reinsertion. The purpose of this study was to investigate the 3-dimensional trabecular bone mineral density (BMD) in the humeral head bone and determine areas of low density. Limited information exists for humeral head to understand its mechanical behaviour.

Materials and Methods: 15 unpaired fresh humeral heads were harvested and frozen. The mean age was 75 years old. All abnormal bones underlying fractures, major arthrosis or surgical interventions were excluded from the study All the heads were scanned using a three-dimensional HR-pQCT system providing 80 microns slices nominal resolution. Manually outlining of the contours of cancellous bone was done in different areas: lesser tuberosity, greater tuberosity, articular part and centre. The parameters included in the analysis were: bone volume density (BV/TV, Trabecular thickness (tb.Th)(mm), Trabecularseparation(TB.Sp)(mm), Trabecular number(TB.N. (1/mm)

Results: The average density of the lesser tuberosity is the highest of the whole head (BV/TV= 0,228). The centre of the head is devoided of large trabeculae with a very low density (BV/TV =0,1). The greater tuberosity is rich in thin trabeculae (Tb Th = 0,265) separated by large spaces (1,5). The articular part presents the higher density (BV/TV =0,3).

Conclusions: Emphasis has traditionally been placed on cortical bone as quality predictor due to its stiffness for achieving primary stabilisation. However screws and anchors are mainly in contact with cancellous part of bone, and mechanical characteristics of cancellous bone also influence the load-bearing capacity of implant –bone union This studies is interesting in showing areas of poor cancellous bone quality and may help to improve surgical techniques.

Introduction: Early mortality associated with unstable pelvic ring injuries is often secondary to continuous pelvic bleeding. Hemostatic measures such as pelvic binders or external fixation may help to control low pressure bleeding from lacerated veins or broad fracture surfaces, while control of high pressure arterial bleeding may require embolization.

Purpose: Evaluate our experience with the control of hemorrhagic shock associated with pelvic ring injuries during initial patient management.

Methods: From January 2003 until December 2006, all [105] patients admitted to our level I trauma center with a pelvic or an acetabular fracture were prospectively entered into our polytrauma data base. Of 105 patients, 67 were classified with a type B or C pelvic fracture. All these patients received a pelvic strap belt by the paramedic team at the scene of the accident. Pelvic fractures were diagnosed on the initial anteroposterior pelvic radiograph and computed tomography. From this initial group of 67 patients, we identified 38 as unstable requiring blood transfusion and intensive care monitoring. The results and survival rate were evaluated according to the initial sequence of surgical procedures and the patients were divided into 3 groups, X,Y, and Z Follow-up physical examination and radiographs was performed for all survivors at an average of 10 months post-injury (range, 6 months to 3 years).

Results: The average age of the 38 patients was 38.6 years (range, 24–51 years) and their average ISS was 53 (range 21–75).All were injured in a high velocity motor vehicle accident or a fall from a height. The patients were managed in the emergency department by a multidisciplinary team according A.T.L.S. guidelines. Of the 38 patients, five died shortly after arrival in the emergency department despite resuscitation efforts. Within the first 24 hours, pelvic stabilization was performed in 27 patients with either an anterior external fixator frame (n=13), pelvic clamp (n=11) or primary open reduction internal fixation (n=3). In group X, of 19 patients initially treated with external fixation and eventual arterial embolization without laparotomy, 18 (94 %) survived. In group Y, there were 8 patients treated by external fixation, eventual arterial embolization and laparotomy, and 7 (87 %) survived. In group Z, all 6 patients in whom a scratch laparotomy with packing prior to any skeletal fixation was attempted,no patient survived ! All survivors underwent definitive open reduction and plate and screw fixation, with an average ICU stay of 10 days (3–15).

Conclusion: This study shows that optimal control of bleeding associated with pelvic ring injuries is achieved by initial skeletal fixation prior to any other surgical procedures. Immediate laparotomy was associated with a high rate of intraoperative death due to the failure to control bleeding.

Objectives: The aim of this study was to quantify bone microarchitecture within the glenoid fossa of the scapula.

High-resolution micro-computed tomography ([mu]CT) imaging have been instrumental in providing true quantitative and qualitative three-dimensional data on baseline bone morphology

Materials and Methods: 25 fresh-frozen human cadaveric shoulders were analysed. The mean age of the specimens was 66 years. All scapulae were inspected for normal anatomic landmarks.

The glenoids were cut at the glenoid neck and at the base of the coracoid process.

The total, trabecular, and cortical BMDs of the 5 regions of the glenoids were determined by use of peripheral quantitative computed tomography (pQCT) (Xtrem Ct;Scanco, Zurich, Ch) Each glenoid was fixed horizontally in a custom-made jig, and axial pQCT scans (pixel size,1536/1536; slice thickness 80 microns), perpendicular to the articular surface, were obtained at the level of each area. From the resulting binarized three-dimensional reconstruction, Scanco software was used to calculate the bone volume per tissue volume; mean trabecular separation; mean trabecular number, connectivity density.

Results: The total BMD of the posterior and superior glenoid were significantly higher than those of the anterior and inferior glenoid. Trabecular BMD of the posterior glenoid was significantly higher than that of the anterior glenoid, and cortical BMD of the superior glenoid was significantly higher than that of the inferior glenoid.

The mean total BMD in different regions of 20 glenoid specimens ranged from 0,243 to 0,489 g/cm2. The center of the glenoid was surprisingly poor in trabecular structures as we found a bony gap at 8 mm of distance from the articular surface.

Conclusions and clinical relevance: Although the specimen age was quite high in our material, we believe aging does not affect our study as shoulders prosthesis are generally performed on old patients.

In the future, component design should use areas of stronger subchondral bone. Posterior and superior bone area could be another alternative for fixation in decreasing glenoid-loosening rates. As the inferior center of the glenoid is an area devoided of trabecular bone, center-keel design component doesn’t seem to be the best choice.

Introduction One of the most difficult aspects of shoulder arthroplasty is retroversion. The ideal angle is about 30 of posterior rotation of humeral head with regard to the frontal plane so that the humeral head squarely faces the glenoid surface in the resting position. The axis, lateral epicondyle- medial epicondyle is often taken as reference and serves as landmark in many arthroplasty instrumentation. [1,2]

Clinical experience has shown that estimating a 30 angle in space is definitely not easy even with the help of diverse goniometers.

Methods Each operator has to put 3 prostheses with a 30 degrees retroversion according to the position of the forearm so we had proceeded to 52 putting of prostheses .

The measures were made by taking into account of the humerus axis, the plan of condyles and angle of inclination of the collar, given by the angle of cutting. Three barycentres of the three humeral sections have determined the humeral axis. The condylar axis is determined from the 2 barycentres of the digitalized points on the anterior articular condylar surfaces. These 2 axis determine the frontal plane on which a reference mark R(x, y, z) is attached with Z lined up with the humeral shaft and X lined up on the condyles. Different angles could then be determined.

In the sagittal plan (perpendicular in the humeral axis), the retroversion angles of the prosthesis and the angle of cutting are calculated.

Results The standard deviation of the retroversion angle of the prosthesis is 14,22 which is really too high. In fact, 4 prostheses were inserted with poor retroversion (17°, 17°, 18°, 4,4°) and 20 with excessive retroversion (max =65°). This retroversion angle is not dependant on the other factors (cut angle, inclination angle...) The implant height was not taken into account

Conclusions Only 28 of the prostheses were placed in the right orientation within 20° to 40° of retroversion angle. It shows the difficulties to place a shoulder prosthesis in good position.even in standard conditions and with the standard marks.