Trauma surgeries in the pelvic area are often difficult and prolonged processes that require comprehensive preoperative planning based on a CT scan. Preoperative planning is essential for the appreciation and spatial visualisation of the bone fragments, for planning the reduction strategy, and for determining the optimal type, size, and location of the fixation hardware.

We have developed a novel haptic-based patient specific preoperative planning system for pelvic bone fractures surgery planning. The system provides a virtual environment in which 3D bone fragments and fixation hardware models are interactively manipulated with full spatial depth and tactile perception. It supports the choice of the surgical approach and the planning of the two mains steps of bone fracture surgery: reduction and fixation. The purpose of the tool is to provide an intuitive haptic spatial interface for the manipulation of bone fracture 3D models extracted from CT images, to support the selection of bone fragments, the annotation of the fracture surface, the selection and placement of fixation screws, and the creation and placement of fixation plates with an anatomically fit shape.

The system incorporates ligament models that constrain the bone fragments motions and provides a realistic interactive fracture reduction support feeling to the surgeon. It allows the surgeon to view the fracture from various directions, thereby allowing fast and accurate fracture reduction planning. Two haptic devices, one for each hand, provide tactile feedback when objects touch without interpenetrating. To facilitate the reduction, the system provides an interactive, haptic fracture surface annotation tool and a fracture reduction algorithm that automatically minimises the pairwise distance between the fracture surfaces. For fracture fixation, the system provides a screw creation and placement capability as well as custom anatomical-fit fixation plate creation and placement. The screw placement is facilitated by the transparent viewing mode that allows the surgeon to navigate the screws inside the bone fragments while constraining them to remain within the bone fragments with haptic forces.

Our experimental results with five surgeons show that the method allows highly accurate reduction planning to within 1 mm or less. To evaluate the alignment in terms of quantity, we created a model of an artificial fracture in a healthy pelvis bone. The created model is placed in its anatomic location thus allowing us to measure the error in relation to its initial position. We calculate the anatomic alignment error by measuring the Hausdorff distance in mm between the fragment positioned in the desired location and the fragment placed by the surgeon. The new haptic-based system also supports patient-specific training of pelvic fracture surgeries.

Purpose: This study attempted to determine if the form of feedback provided by a computer-based navigation technique improves the learning of the placement of cannulated screws across a femoral neck fracture in the surgical trainee.

Method: A prospective, randomized, appropriately powered, and controlled study involving 39 surgical trainees (first-year residents and fourth-year medical students) with no prior experience in surgically managing femoral neck fractures were used in the study. After a training session, participants underwent a pretest by performing the surgical task on a simulated hip fracture using fluoroscopic guidance. Immediately after, 20 participants were randomized into undergoing a training session using a conventional fluoroscopy-guided technique while the other participants were randomized into undergoing a training session using a computer-based navigation technique. Immediate post-tests and retention tests (4 weeks later) were performed. A transfer test was used to assess the impact of the type of training on surgical performance – after performing the retention test, each group repeated the task but used the other technique to guide them (i.e. those trained with fluors-copy used computer navigation and vice versa).

Results: Screw placement was equal and to the level of an expert surgeon with either training technique during the post-, retention, and transfer tests. Participants that were trained with computer navigation took fewer attempts to position hardware and used less fluoroscopy time than those that trained with fluoroscopy. When participants that trained with computer navigation reverted to conventional fluoroscopic technique at the transfer test, more fluoroscopy time and dosage was used. Participants that trained with fluoroscopy used less fluoroscopy time and took fewer attempts to position hardware when they subsequently used computer navigation to perform the task during the transfer test.

Conclusion: Computer navigation does not harm the learning of surgical novices in this basic orthopaedic surgical skill. Training with computer navigation minimizes radiation exposure and decreases the number of attempts to perform the task. No compromise in learning occurs if a surgical novice trains with one type of technology and transfers to using the other.

Background: The purpose of this study was to analyze the applicability and advantages of the intraoperative use of a mobile isocentric C-arm with 3-dimensional imaging (SIREMOBIL ISO-C-3D) in fixation of intraarticular fractures.

Methods: Intraoperative CT-quality visualization was performed on a series of 72 closed-intraarticular fractures in 70 patients following fixation. Fracture distribution was; calcaneus (25), tibial plateau (17), tibial plafond (12), acetabulum (11), distal radius (3), ankle (3), femoral head (l). The mean patient age was 41. Intraoperative revision was performed based on the additional information Iso-C-3D provided beyond routine fluoroscopy used for fracture reduction and fixation. The primary outcome measure was revision rate after final Iso-C-3D data acquisition and prior to wound closure. Secondary objectives were to measure the additional time required for Iso-C-3D use and to determine the rate of further re-do surgeries.

Results: Eight out of 70 (11%) fracture fixations were judged by the surgeon to require intraoperative revision following Iso-C-3D imaging. In 7 cases this was due to hardware misplacement and in 1 this was for intraarticular loose fragment. Prior to leaving the operating room, the surgeon was satisfied with fracture alignment in all the procedures. The mean additional operative time using Iso-C-3D was 7.5 minutes. No patient required re-do surgery.

Conclusion: Intraoperative 3-dimensional visualization of intraarticular fractures enables the surgeon to identify inadvertent malreductions or implant malpositions which may be overlooked by routine C-arm fluoroscopy and hence eliminates the need for re-do procedures. Iso- C-3D adds little operative time and may preclude the need for preoperative and postoperative CT-scans in selected cases.

Introduction: Cell-based strategies for regeneration and reconstitution of musculoskeletal tissues are gaining interest. The difficulty in obtaining the required amount of mesenchymal stem cells (MSC) stems from their scarcity and the time needed to grow them in culture. We developed a rapid and efficient method to isolate MSC from bone marrow aspirate based on their surface markers, as a platform for future cell based therapy.

Methods: Bone marrow was aspirated from the iliac crest of fifteen adult subjects undergoing surgeries involving this bone. 15 ml samples were obtained, fractionated for mononuclear cells and then subjected to immunomagnetic isolation using microbeads of directly conjugated mouse anti–human CD105 antibodies. Recovered cell fraction was analyzed for phenotype and functional parameters.

Results: The samples yielded an average of 14.6±2.5x10⁶ mononuclear cells per ml. Of these, fraction of CD105 positive cells consisted of 2.3±0.45%, which accounts for 0.25±0.06x10⁶ cells per ml. Post isolation analysis shows that 79±3.2% were positively stained for CD105 and 36±5.8% stained positive for CD45. These cells generated 6.3±1.4 Colony Forming Units (CFU) per 10⁵ cells. MSC concentration is higher in males and lower in smokers. Processing time is approximately 3 hours.

Discussion and Conclusion: Regeneration of mesenchymal tissues using progenitor cells with appropriate matrix and signals was shown feasible, however large numbers of these rare cells are needed. An effective and safe method for purification of autologous MSC enables us to avoid the risks and the time span associated with culture expansion. We conclude that this method is both effective and rapid.

Introduction: Fluoroscopy-based navigation systems enables surgeons to place implants with a simultaneous multi-planar monitoring. Percutaneous fixation of femoral neck fractures is an example of the growing usage of these systems in orthopedic trauma surgery. Growing evidence suggests that the accuracy of screw placement might affect the fracture outcome.

Methods: Between 2/2001 and 8/2005, 80 patients underwent internal fixation of femoral neck fractures using computerized navigation system. Three cannulated screws were implanted in an inverted triangle formation. The average patient’s age was 62±20 years (range 11–88), and 12 patients were under the age of 40 years. 53 patients were female, 27 male. 68 patients sustained the fracture due to a simple fall, 4 fell from high ground, 3-bicycle injuries, 2 due to motor vehicle accidents, and 3 patients suffered from insufficiency fractures with no trauma. The data includes results for both undisplaced fractures and fully displaced fractures which underwent closed reduction.

Results: The average length of hospital stay was 6.3±4 days (range 1–19). The average operating room time was 82±22 minutes (range 30–135), this including the preparation of the patient and instrumentation. Complications included one case of infection which necessitated long term antibiotic treatment, four patients requiring hip arthroplasty due to avascular necrosis of the femoral head, and one patient who underwent hip arthroplasty due to osteoarthritis. The total failure rate is 6%.

Conclusions: Computerized navigation for the internal fixation of subcapital femoral neck fractures allows improved screw positioning, which may reduce fracture complications, and provides reduced radiation to both the surgeon and the patient.

Introduction: To enable navigated-assisted orthopedic surgery, a reference frame must be rigidly fixed to a stable bony structure. This may create technical obstacles and wound complications. Instead, we propose to attach the reference frame to the fracture table.

Methods: The study population consisted of 10 patients who underwent fixation of subcapital femoral neck fracture with three cannulated screws, using fluoroscopy-based navigation. Step 1 – the patient was positioned on a fracture table and the reference frame was attached to the iliac crest. Three guide wires were inserted under fluoroscopy-based navigation. 2 – New fluoroscopic images were acquired. 3 – Navigated drill guide placed over each guide wire to record final navigated drill guide position – these images include actual guide wire positions and the trajectories of the navigated drill guide. Navigation accuracy was validated, measuring translational and angular deviations of the virtual trajectory from the implant on the same fluoroscopic image in anteroposterior and lateral views. 4 – The reference frame was removed from the iliac crest and attached to the fracture table. Step 3 was then repeated.

Results: The translational deviation of the virtual trajectory from the inserted guide wire when the reference frame was attached to the iliac crest was not statistically significant from the deviation when it was attached to the fracture table. Angular differences were also not statistically significant.

Conclusions: In our experience, attaching the reference frame to the fracture table instead of to the iliac crest allows for similar accuracy of the navigation process with the possible benefit of reducing patient morbidity.

Background: The purpose of this study is to evaluate the applicability and advantages of the intraoperative use of a mobile isocentric C-arm with 3-dimensional imaging (SIREMOBIL ISO-C-3D) in trauma surgery.

Patients & Methods: Between November, 2004 and September, 2005, the ISO-C-3D was used at our institution for intraoperative CT-quality visualization of 33 trauma cases with the fractures of calcaneus (13), tibial plateau (7), tibial plafond (6), acetabulum (4), distal radius (2) and talus (1). The mean patient age was 42 and male to female ratio 25 to 8. In 30 cases ISO-C-3D was used during the surgery after the reduction and fixation of the fracture to assess the accuracy of reduction and implant position prior to wound closure and in 3 cases the device was used before starting the operation to obtain real-time CT images which were transferred to a navigation system to perform computer navigated procedures.

Results: This novel technique was highly beneficial from 4 aspects; intraoperative diagnosis, proper reduction, correct implant placement and feasibility in combining the CT images to computer navigation. In 40% of the cases (13/33) who had no regular CT scan before the surgery, intraoperative three dimensional imaging with ISO-C-3D has been a superior modality in diagnosis. In one case the reduction and implant position was corrected during the surgery after the ISO-C-3D scan. In all the procedures with ISO-C-3D navigation, satisfactory reconstruction of the articular surfaces with precise fixation was achieved.

Conclusion: Intraoperative 3-dimensional visualization with ISO-C-3D provides useful information in trauma surgery which enables the surgeon to re-evaluate the injury diagnostically and to judge the reduction and implant position before wound closure. Combining the ISO-C-3D images with computer navigation makes the reduction and implant placement highly accurate.

Introduction: Non union of the humerus in the ostoeportic bone is a great challenge for the orthopedic surgeon. The non weight bearing nature of this bone together with extreme osteoporosis seen in the elderly had rendered a high degree of failure in different modes of internal fixation of established humeral non union. Tantalum is a trabecullar metal with biomechanical properties similar to bone with a high modulus of elasticity and low rigidity. It is proved both in vitro and in vivo to induce excellent bone and vascular in growth and have been used successfully treating other application in orthopedics. We have introduced the tantalum rod for the treatment of humeral non union in the elderly.

Patients and Methods: Six patients with humeral non-union were selected for tantalum rod implantations. All were above 60 years old. All patients had established non and 4 had failures after previous osteosynthesis. The surgical technique was exploration of the fracture site via a posterior or an anterolateral approach, debridement of the fracture site and intramedullary insertion of a 100 mm x 10 mm tantalum rod. No bone grafting was used. Ancillary fixation included a 4.5 broad DCP plate with screws drilled into both bone and rod or screws alone drilled into the bone and tantalum construct. Follow up period was up to one year.

Results: All fractures united clinically and radiographicaly up to 3 months. All patients achieved satisfactory shoulder and elbow range of motion and regained functional activity. No infection or foreign body reaction was noted.

Conclusion: Intramedullary tantalum rodding is a viable treatment option for the cases in both primary and secondary non union of the humeral shaft in osteoporotic bone.

Introduction: Numerous studies had been published concerning the classification, biomechanics and the management of penetrating extremity trauma involving long-bone fractures. Significant controversy exists in protocols of the management and outcomes of these serious injuries. Bullets and multiple shrapnel injuries due to terror attacks may differ in injury pattern and severity. The role of immediate internal fixation still remains questionable. During a period of four years 92 patients suffering from 103 long bone fracture due to penetrating gunshot and shrapnel injuries were treated in our level I trauma center. The aim of this retrospective study is to evaluate the outcome of these patients regarding our treatment protocol.

Patients and Methods: 92 patients suffering from 113 long bone fractures caused by firearms and shrapnel injuries were treated in a level I trauma centre between 1/2000 and 12/2003. There were 36 femoral fractures, 50 tibial fractures, 5 humeral fractures and 24 forearm fractures. 43% of the patients suffered from associated injuries. Fifty eight percent of the patients had an Injury severity score (ISS) of 9–14 and 21% had an ISS greater than 25. 30% of the patients suffered form an associated vascular injury and 32% from an associated nerve injury of the fractured extremity. 36% of patients had multiple fractures. Overall mortality rate was 4%.

Results: 77% of the fractures were fixated primarily and 23% were splinted or put in a cast. 3% of limbs were amputated. Out of the primary fixation group, 45% of the fractures were fixed with intramedullary nails, 44% with an external fixator and 11% with plates. 28% of the fractures required arterial repair, 18% required nerve repair and soft tissue coverage procedures were needed in 14% of the fractures.

The infection rate for the entire group was 12%. Non-union occurred in 8%. Secondary amputation rate was 4%

Discussion: The surge of violence in our region had produced penetrating long bone injuries with increased severity, often associated with polytrauma, differing from other published series. Our management of these serious injuries was aggressive with the increased use of primary intramedullary nailing and internal fixation with comparable results of other published series. We conclude that aggressive primary surgical approach using multidisciplinary teams can result in favourable results in these unique patients subset.

Introduction: Minimally invasive surgery (MIS) is associated with reduced postoperative morbidity and faster recovery of function. The PerCutaneous Compression Plate (PCCP) device was recently developed by Got-fried as a MIS technique for the fixation of osteoporotic hip fractures. PCCP provides rotational stability by means of two hip screws, and lateral cortical support by a proximal extension of the plate and by the relatively small diameter (9.3 mm) of the hip screws. The purpose of this prospective study is to compare the outcome of PCCP to the “gold standard” Compression Hip Screw (CHS) device.

Methods: 104 Patients with intertrochanteric fractures were randomized to be treated by PCCP (50 patients) or CHS (53 patients). One patient was switched from PCCP to CHS during surgery. Inclusion criteria were age above 60, close fracture reduction, no pathological fracture, and no surgical procedure in the same leg in the last year.

Results: The groups were comparable in patient age, gender, ASA, length of surgery and hospital stay. Operative blood loss was 177.8 ml in the PCCP group and 371.3 ml in the CHS group (p< 0.0001). At the 6^th week clinic visit, patients in the PCCP group were able to bear more weight on the injured leg than patients in the CHS group (p< 0.03). Mortality during the first year follow-up period was 10% in the PCCP group and 24.5% in the CHS group (p~0.05). Analysis of X-ray radiographs revealed collapse in 4% of the patients in PCCP group and 19% in CHS group (p< 0.01).

Conclusions: Our results suggest that PCCP provides some of the advantages of MIS: reduced blood loss, as well as improves the stability of fracture fixation, demonstrated by improved early weight bearing and less fracture collapse. We found a trend for decreased first year mortality rate.

Introduction: Cementless hydroxyapatite coated prosthesis are mainly selected for a relatively young and active patient population. Most clinical studies demonstrate excellent osseous integration of the HA coating and good outcome. The clinical follow-up reports of the ABG group suggest excellent results, however we observed an alarming rate of acetabular osteolysis and polyethylene wear which required revision surgery. Thus a comprehensive retrospective evaluation of all operated patients had been conducted.

Patients and Methods: 162 ABG hips were replaced in 148 patients, of them 75 patients were studied and followed-up. Mean age was 56 (range 33–71). 48 patients were women and 27 were men. 8 patients had bilateral hip replacement. Etiology of hip disease varied and included primary osteoarthritis (27 patients – 36%), congenital hip dysplasia (24 patients – 32%), osteonecrosis (12 patients – 16%), ankylosing spondylitis (5 patients – 6.6%), post traumatic arthritis (5 patients – 6.6%) and post-infectious arthrosis (2 patients – 2.6%). Postoperative follow-up period averaged 4 years (range 15–80 months).

Results: The mean postoperative Harris hip score was 89 (range 52–100). 23 patients (30%) reported of modified life activity after surgery, and the majority had resumed their previous occupations.

Complications included 3 early and one late dislocations – one patient required an early cup revision, one patient suffered a fracture of the femur during stem insertion, and 3 patients (4%) had deep vein thrombosis. There was one case of a femoral vein injury and one resolving superficial infection. No deep infections were noted.

13 patients had undergone cup revision due to severe polyethylene wear and periacetabular osteolysis. Of them 5 were diagnosed during this retrospective study and 8 were referred for revision due to clinical symptoms. Thus the revision rate of the entire operated population is 13/162 = 8.0% and 13/75 = 17.3% of the studied patients. The true loosening rate should be between these 2 figures.

In 2 patients the entire cups were removed and revised due to loosening. In 11 patients following the removal of the polyethylene inserts the metal back proved to be stable. In these cases the bone defects were filled-up with bone graft substitute, and a highly cross-linked polyethylene (22 mm head) were cemented into the metal shell. No stems needed revision.

Conclusion: In spite of a relatively high Harris Hip Score and generally good long-term follow-up a high rate of acetbular lysis and polyethylene wear were observed. This observation warrants avoiding the use of the ABG cups until further investigation is performed. A continued clinical and radiographic analysis is required for the entire operated patients. In all cases of polyethylene wear or significant osteolysis revision is indicated.

Background: Osteoarticular disease is the most common complication of brucellosis and has been described in 10–85% of patients. Spondylitis is the most prevalent clinical form, also arthritis, bursitis, tenosynovitis, sacroileitis and osteomyelitis have been also described.

Method: We describe our experience concerning three patients with brucellar prosthetic joint infection in Israel.

Results

Case 1: A 38 year old artist was admitted for revision of total hip replacement due to increased pain accompanied by loosening of the prosthesis. Four years prior admission total hip arthroplasty was performed due to psoriatic arthritis treated by methotrexate. Revision surgery demonstrated necrotic tissue which grew Brucella melitensis. Doxycycline and rifampicin were administered for 12 weeks. Second stage revision was performed on the 6th week of antibiotic therapy with favorable results.

Case 2: A 62 year old Arab male underwent right total knee arthroplasty 4 years prior admission due to osteoarthritis. Past medical history included hip arthritis. A second TKA was performed due to septic arthritis caused by Staphylococcus epidermidis and Acinetobacter baumanii. The first stage of the arthroplasty grew Brucella melitensis.

Antibiotic treatment and second stage revision surgery were followed successfully.

Case 3: A 67 year old Arab male was admitted due to fever, right pelvic and back pain lasting for 6 weeks. Five years prior admission the patient underwent left total knee arthroplasty. Computerized tomography was normal. Following admission severe left knee pain developed. Joint aspirate grew Brucella melitensis. Antibiotic treatment and two stages revision surgery were performed successfully.

In all three cases consumption of unpasteurized dairy products was documented. All three patients had serum brucella antibody titer of 1:1600.

Conclusion: Brucella melitensis should be added to the differential diagnosis of prosthetic joint infection, mainly in the Mediterranean basin and the Arabian Gulf. Only two other cases of brucella prosthetic joint infections were reported involving prosthetic knees.