The treatment of joint-fractures is a common task in orthopaedic surgery causing considerable health costs and patient disabilities. Percutaneous techniques have been developed to mitigate the problems related to open surgery (e.g. soft tissue damage), although their application to joint-fractures is limited by the sub-optimal intra-operative imaging (2D- fluoroscopy) and by the high forces involved. Our earlier research toward improving percutaneous reduction of intra-articular fractures has resulted in the creation of a robotic system prototype, i.e. RAFS (Robot-Assisted Fracture Surgery) system.

We propose a robot-bone attachment device for percutaneous bone manipulation, which can be anchored to the bone fragment through one small incision, ensuring the required stability and reducing the “biological cost” of the procedure. It consists of a custom-designed orthopaedic pin, an anchoring system (AS secures the pin to the bone), and a gripping system (GS connects the pin and the robot). This configuration ensures that the force/torque applied by the robot is fully transferred to the bone fragment to achieve the desired anatomical reduction.

The device has been evaluated through the reduction of 9 distal femur fractures on human cadavers using the RAFS system. The devices allowed the reduction of 7 fractures with clinical acceptable accuracy. 2 fractures were not reduced: in one case the GS failed and was not able to keep the pin stationary inside the robot (pin rotates inside the GS). The other fracture was too dislocated (beyond the operational workspace capability of the robot). A more stable GS will be designed to avoid displacements between the pin and the robot.

Background

Treating fractures is expensive and includes a long post-operative care. Intra-articular fractures are often treated with open surgery that require massive soft tissue incisions, long healing time and are often accompanied by deep wound infections. Minimally invasive surgery (MIS) is an alternative to this but when performed by surgeons and supported by X-rays does not achieve the required accuracy of surgical treatment.

One of the more difficult tasks in surgery is to apply the optimal instrument forces and torques necessary to conduct an operation without damaging the tissue of the patient. This is especially problematic in surgical robotics, where force-feedback is totally eliminated. Thus, force sensing instruments emerge as a critical need for improving safety and surgical outcome. We propose a new measurement system that can be used in real fracture surgeries to generate quantitative knowledge of forces/torques applied by surgeon on tissues.

We instrumented a periosteal elevator with a 6-DOF load-cell in order to measure forces/torques applied by the surgeons on live tissues during fracture surgeries. Acquisition software was developed in LabView to acquire force/torque data together with synchronised visual information (USB camera) of the tip interacting with the tissue, and surgeon voice recording (microphone) describing the actual procedure. Measurement system and surgical protocol were designed according to patient safety and sterilisation standards.

The developed technology was tested in a pilot study during real orthopaedic surgery (consisting of removing a metal plate from the femur shaft of a patient) resulting reliable and usable. As demonstrated by subsequent data analysis, coupling force/torque data with video and audio information produced quantitative knowledge of forces/torques applied by the surgeon during the surgery. The outlined approach will be used to perform intensive force measurements during orthopaedic surgeries. The generated quantitative knowledge will be used to design a force controller and optimised actuators for a robot-assisted fracture surgery system under development at the Bristol Robotics Laboratory.

Despite the in-depth research into the treatment of acute septic arthritis of the knee, the morbidity and mortality are still significant.

The purpose of our study was to evaluate the efficacy of a treatment protocol including arthroscopic irrigation and debridement in resolving septic arthritis of the knee.

During a 6-year period, 18 patients presenting with septic arthritis of the knee were included in this study. In 10 cases, septic arthritis occurred after knee arthroscopy, in 2 after open trauma, in 2 more after joint aspiration or injection; there were 2 hematogenous infections and 2 following contiguous spread from an adjacent site. The patients were treated with an arthroscopic debridement protocol consisting of (1) arthroscopic debridement and synovectomy, (2) suction drainage for 24 hours, (3) repeat arthroscopy for persisting clinical and laboratory findings and (4) antibiotics IV for four weeks and per.os. for two months (ciprofloxacin – rifampicin). The onset of the symptoms presented 18.2 days in average after the cause. The patients complained of swelling (18/18), fever ~39° C (16/18), stiffness (13/18), pain (12/18), erythema (6/18) and weakness (6/18). Arthroscopic drainage (average 1.5 procedures) was performed at an average of 8.4 days from the initiation of the symptoms. Laboratory data revealed elevated ESR (erythrocyte sedimentation rate) (average 68.9), CRP (average: 10.9) and WBC (average: 8894.3).

The mean follow-up period was 3.5 years. Cultures from knee joint aspirations were negative in 9 cases. Five knees were infected with Staphylococcus aureus, 2 with Staphylococcus epidermidis, 1 with Escherichia Coli and 1 with multiple organisms. One month after the last arthroscopic debridement, the ESR and CRP levels were normalised in all cases. Lysholm scores averaged 91. Most of the patients (15/18) returned to their pre-infection level of functioning. Overall success in clinical eradication of infection was 100%.

Our conclusions are:

early aggressive arthroscopic debridement as part of a treatment protocol can be an effective treatment option,

Aims: To evaluate the long-term results of arthroscopic meniscal repair of any longitudinal meniscal tear in red-red or red-white zone. Methods: 60 patients 30.5 years old average (range 15 to 50) underwent arthroscopic meniscal repair (Ç inside-out È technique, Jacobs-Staue-bli method, 1988) and were followed up 30.1 months on average. 34 patients (50%) had an additional ACL rapture, which was repaired at the same operation. Postoperatively, all patients followed a particular program of rehabilitation using a controlled motion knee brace: immediate weight-bearing with the brace locked in 10¡, motion without weight-bearing from 10 to 90 degrees of ßexion for the þrst six weeks and then weight-bearing in motion was allowed. Results: Patients were re-examined and average Lysholm score was 95, while recurrence occurred in 5 patients (7.3%) and 3 of them submitted to meniscectomy. The rest of the patients returned to their former activities in a six-month period, including those who underwent an ACL reconstruction. Conclusions: Arthroscopic meniscal repair has excellent functional results and should always be applied on any longitudinal meniscal tear in red-red or red-white zone. Additional ACL ruptures should be treated at the same time.

Aim: We report on the use of external þxation as an alternative þxation of femoral fractures in patients where internal þxation is a borderline indication. Patients and method: From 1991 to 2001, twenty-þve patients with femoral diaphysis fractures were treated by external þxation. Indications included candidates with multiple injuries and unstable general condition, open fractures IIIA, B, C, neglected open fractures with or without infection, comminuted shaft fractures, gunshut injuries and infections after internal þxation. The fractures were stabilized with a unilateral external þxation or with a special anti-varus frame. Results: In twenty patients, external þxation was the deþnitive method of stabilization, while in þve, it was a temporary method. The average time to union was 5 months. Complications included: pin tract infection, restricted knee motion, and loss of reduction. Conclusion: External þxation should not be routinely used for þxation of femoral fractures, but may be considered in multiply injured and critically ill patients. As in any method of þxation, the surgeon must be familiar with the device used, the mechanical and the application properties of such devices, and, most importantly, the postoperative management of the patient.

Aim: The role of external þxation in the deþnite management of open tibial fractures is reviewd based on a study of 180 tibial fractures during 1992– 2001. Method: From the 180 patients, 70 fulþlled the criteria (anatomical or acceptable reduction, optimal fragmemts contact, high rik for infection, technical difþculties for internal þxation) and was included to the study. Fractures were stabilized with a unilateral frame, or with V or delta frame. In sixty-one cases, bony consolidation in optimal aligment occurred. In the remaining nine patients, external þxation was removed because of major pin tract infection, loss of reduction or in delayed union. Results: Sixty-one patients achieved union with the external þxation in a mean time of 4,5 months (3 to 6 months). There was no malunion. Minor pin track infection was seen in 32/280 pin sites (11.4%). No remarkable shortening of the injured leg observed. After consolidation, 44 (72.1%) fractures had a very good or good functional recovery. An acceptable result was achieved in 16 patients (26.3%), and one (1.6%) had bad function of the injured leg. Conclusion : Given the stringent adherence to the important principles of þxator application, attentive choice of the patient and the type of the fracture, and well supervised follow up, we believe that deþnitive, successful management of open tibial fractures can be obtained with external þxation.

Aims: a) To review donor site morbidity and record problems coming out during bone harvesting, b) to evaluate bone graft adequacy and effectiveness. Methods: Senior author operated 127 patients using cancellous bone autografts (from May 1988 to September 2001). Bone grafts were obtained from iliac crest (83 patients), proximal tibial metaphysis (39 patients) and other donor sites (5 patients). In all cases intraopera-tive problems and early postoperative problems were recorded. Late postoperative problems were evaluated either subjectively (questionnaire) or clinically for 109 patients. Minimum length of follow up was 12 months. Results: In all the cases, the goals of graft harvesting were accomplished. Generally, grafts were adequate in quantity and quality (apart from 2 cases in which grafts were taken from proximal tibial metaphysis). Blood loss from the proximal tibia was less than iliac bone. Iliac pain was more severe than tibial, resulting to delayed mobilization and pain could persist for a long period of time. Conclusions: Proximal tibial metaphysis, as a donor site, is associated with far less morbidity than iliac and it should be chosen in patients with lower-extremity fractures or nonunions. Harvesting from tibia is adequate and easier comparing to iliac. Tibial bone grafts were as effective as iliac, despite that iliac bone graft is widely used and generally referred as a better quality autologus bone graft.