[The Department of Orthopaedics and Traumatology of the University Clinics of Brussels, Erasme Hospital]. / Le Service d'Orthopédie-Traumatologie des Cliniques Universitaires de Bruxelles, hôpital Erasme.

On the occasion of the thirty years since its inauguration, the Department of Orthopaedics and Traumatology of the University Hospital Erasme reviews the milestones of its development. Various original new techniques have been implemented: monitoring of implants using strain gauges, external fixation of the limbs, external minifixation, miniinvasive anterior approach in hip arthroplasty, knee ligamentoplasties, orthopaedic microsurgery and composite tissue allotransplantation. The care of aged patients takes place in close collaboration with the Department of Geriatrics. Two new clinical units have been created, the Unit of Hand and Peripheral Nerve Surgery, and the Centre for Sports. The Department has organized an efficient Bone Bank. The new day care hospital improves the possibilities of ambulatory surgery. The article details as well the activities of teaching and research of the members of the Department.

[Historical review of the treatment of fractures. Contribution of the Belgian surgery to the origin and development of osteosynthesis]. / Aperçu historique du traitement des fractures. Apport de la chirurgie belge dans la naissance et le développement de l'ostéosynthèse.

The word osteosynthesis was proposed by A. Lambotte in 1904. His definition, given in 1908, is still valid today: "Osteo-synthesis is the artificial contention of the bone fragments of fractures, by special devices acting directly on bones, exposed or not, with the aim to strongly fix them in their original position". The authors review the methods of contention before the invention of osteosynthesis and later the developments of bone fixation techniques. They insist in particular on the durable innovations of various pioneers including A. Lambotte, R. Danis, R. Hoffmann and G. Küntscher. The School of Brussels has been implicated in the developments and conceptualisation of osteo-synthesis.

[Evolution of the biomechanical principle of osteosynthesis]. / Evolution du principe biomécanique des techniques d'ostéosynthèse.

Through the technological evolution of the medical devices used for the treatment of bone fractures, two main concepts are in opposition: the internal rigid and the external elastic fixations. For forty years, the limitation due to the mechanical resistance of the materials have determined the various methods of treatment of fractures and influenced the comprehension of the physiopathology of bone healing. Two main figures of the Belgian orthopaedics and traumatology, Robert Danis and Franz Burny, had a determinant impact in this evolution.

[Study of the plantar arch: correlations between podometrical and radiological parameters. results of a prospective study of 79 cases]. / Etude de la voûte plantaire: corrélations entre des paramètres podométriques et radiologiques. Résultats d'une etude prospective de 79 cas.

The authors present a prospective study on the potential correlations between eight footprint parameters and three radiological parameters in the study of the plantar arch. Seventy nine patients were evaluated in 2001. The eight footprint parameters were as fellows : the arch angle, the Chippaux-Smirak's index, the Quamra's contact index 2,3 and 4, the Schwartz's footprint angle, the Staheli's arch index and the arch length index. The three radiological parameters were as fellows : the Djian-Annonier's angle, the Méary's angle and the calcaneal inclination. This prospective study confirms the best correlation, found in others studies, obtained between the Djian-Annonier's angle and the Chippaux-Smirak. The use of the Méary's angle and the calcaneal inclination is not justified because they have bad correlations with footprint parameters.

[Increasing incidence of knee ligament injuries in alpine skiing: epidemiology and etiopathogenetic hypotheses]. / Incidence croissante des traumatismes ligamentaires du genou lors de la pratique du ski alpin: épidémiologie et hypothèses étiopathogéniques.

20 to 25% of all the injuries are due to traumas of the knee since forty years. The amount of serious sprains has been in constant increasing during the last four decades. The ratio of one to two in 1960 between and ankle injuries was of six to one in 1987. The inversion of this ratio is probably due to the evolution of technics from 1960 forth, to plastic shoes with thicker soles, to the wrong adjustment of binding and to the higher speed of the skiers thanks to better mending of tracks. The frequency of injury of ligamental structures is higher for the internal lateral ligament and for the anterior cruciate ligament. A valgus associated to internal leg rotation in consequence of blocking of internal edge and of forward falling causes internal lateral ligament injury. The three lesional mechanisms of the anterior cruciate ligament are the valgus connected with external rotation, the anterior draw caused by the shoe in case of backward falling and the association valgus-flexion-internal rotation ("foot-phantom"). These lesions of ligaments are often connected with lesions of the external meniscus and with osseous contusions concerning the external femoral condyle and the external tibial plate.

[The orthopedics-traumatology department]. / Le Service d'Orthopédie-Traumatologie.

The Department is involved in clinical and research activities. We pioneered the clinical application of "smart of Orthopaedic implants". The monitoring concept, bringing a high added value, helps in assessing fracture healing or implant fixation. The technique, featuring the 21st century, also requires advanced knowledge in biomaterials. Such implants have been used during the ESA Parabolic Flight Campaigns. These measurements are a prerequisite to establish prevention programs of the bone demineralisation during space flights but also in disuse osteoporosis. The Department is deeply involved in external fixation. In vitro studies of the mechanical insertion and holding parameters of external fixation pins have been performed to produce new implants, which efficiency has been proved by a clinical study. We defined original clinical principles of external fixation as its use in upper limb indications, to maintain microsurgery transplant, preserving devascularization and providing adequate fixation. Our biomechanical approach of the upper limb, now confirmed by others research groups, questioned old clinical concepts. The isokinetic evaluation assesses the dynamic function of articulations, i.e. after arthroplasty, and is also used for medico-legal evaluation. The clinical research touches orthopaedic (or systemic) diseases as algodystrophy, Kienböck disease, Kashing Beck. We conducted a multidisciplinary research on the effect of electromagnetic fields (EMF) on cells differentiation. In addition to possible healing properties, it helps as an objective support to analyse the exposure to the environmental EMF.

Fracture of the posterior aspect of the lateral tibial plateau: radiographic sign of anterior cruciate ligament tear.

Plain radiographs obtained in 25 patients with acute anterior cruciate ligament (ACL) tears detected with magnetic resonance imaging were retrospectively evaluated to identify associated bone lesions. Fracture of the posterior part of the lateral tibial plateau (LTP) was seen in 11 patients, impacted fracture of the lateral femoral condyle (LFC) in two, lateral tibial rim fracture (Segond fracture) in three, and avulsion fracture of the tibial attachment of the ACL in two. The latter three fractures have been associated with an ACL tear. Conversely, fractures of the posterior part of the LTP have not been associated with ACL tear and are recognizable on plain radiographs. Impaction of the LFC on the LTP and avulsion of the posterior tibial capsular junction may account for the association of the fracture of the LTP with the acute ACL tear. This type of fracture represents the most frequent indirect sign of ACL tear seen on plain radiographs.

Transverse geniculate ligament of the knee: appearance at plain radiography.

Visualization of the transverse geniculate ligament of the knee in four patients is described. This normal variant was seen on lateral plain radiographs as a small, rounded opacity surrounded by fatty tissue and located anterior to the knee joint. Magnetic resonance imaging helped confirm this image to be that of the transverse geniculate ligament.

Treatment of forearm fractures by Hoffman external fixation. A study of 93 patients.

Ninety-three patients with acute fractures of the diaphysis of one or both bones of the forearm were treated by a Hoffmann external fixator, using a half-frame configuration. Whenever possible, closed methods of reduction were used. The versatility of the Hoffmann external fixator allows multiple attempts and possible secondary resumption of the reduction. The half-frame configuration is stable enough, allowing the restoration and maintenance of the precise anatomy of the forearm bones and early active postoperative motion. The median length of retention of the external fixator was 13 weeks. Because of the elastic type of fixation, a solid periosteal callus was usually obtained. Non-union occurred in 8.5% of the patients. One refracture at the former fracture site was observed.

Treatment of mandibular fractures by external fixation.

This series encompasses thirteen fractures of the mandible treated by external fixation. The indications were five fractures of edentulous mandible, four fractures through missile wounding, and four fractures without soft tissue lesion treated in Africa. Twelve patients were found to show good or excellent results. In our indications, this method is a successful approach to the treatment of the fractured jaw.

[Osteosynthesis of the clavicle using an external fixator]. / Ostéosynthèse de la clavicule par fixateur externe.

Twenty-four fractures or nonunions of the clavicle were treated by a Hoffmann external fixator, for selected indications. No vascular or pleural complications were observed. All clavicles healed, after a mean duration of 52 days.

External fixation of the clavicle for fracture or non-union in adults.

A technique of osteosynthesis of the clavicle with Hoffmann external fixation was used to treat twenty patients for selected indications, including an open fracture, inability of a patient to tolerate prolonged conservative treatment, or a painful non-union. No vascular or pleural complication was observed. The average time that the external fixator was retained was fifty-one days. All of the clavicles united well. Mobility of the shoulder returned to normal in all patients.

Comminuted fractures of the base of the first metacarpal treated by distraction-external fixation.

A new technique is presented for the treatment of comminuted intraarticular fractures of the base of the thumb metacarpal. A triangular Hoffmann external radius and first- and second-metacarpal fixator is used. The reduction is maintained by prolonged distraction and abduction of the first metacarpal bone. The application of the technique in three cases is reported.

External fixation pin: an in vitro general investigation.

Surgical drilling and pin insertion can lead to mechanical and thermic damage of the bone. A methodology giving reproducible in vitro records of insertion and holding parameters of threaded implants is presented. Both drilling and tapping are related to the cutting technology. To understand the basic principles of the cutting technology some important parameters of drilling and tapping of an external fixation pin are defined. A bone model was selected based on specific mechanical and thermal properties of the bone tissue. In addition, a specific instrumentation was designed in order to compare the insertion characteristics and the anchorage of different pins. Electronic scanning microscopy of the samples was systematically performed to evaluate the quality of the bone thread. The in vitro measurements of the shearing torque and the pull-out force are representative of the immediate holding power of a pin. The different holding parameters were then correlated. Temperature measurements were performed during drilling, smooth part penetration (transfixing pins), tapping, and screwing. The final objective of the study was to develop new threaded implants with better biomechanical characteristics.

[Complications following talus trauma]. / Komplikationen nach Talustrauma.

The injuries of the talus are rare. In this retrospective study, complications of 359 talar lesions are studied. Secondary displacement occurred in 8%. Bone infection remained low in spite of frequent primary skin injury (20%). Bone fusion was slow but no case of non-union could be found. Avascular necrosis of the body or of the trochlea occurred in 33% but could be partially prevented by accurate reduction of the fractured bone. Osteoarthritis occurred in 33%.

Maximum Torque at the Time of Retrieval (MTR).

The MTR can be considered as representative of the quality of the anchorage of a cylindrical implant. We present preliminary investigations in the patients of our "External Fixation Clinic." The quality of the anchorage of the pins may decrease according to the duration of implantation. Appreciation of clinical loosening is valuable and can be used to roughly assess the quality of the anchorage.

External fixation of the fracture of the humerus: a review of 164 cases.

During our experience with external fixation for the fractures of the shaft of the humerus since 1967, the indications have been extended to include complex metaphyseal and epiphyseal fractures of both the proximal and the distal part of the bone. We propose elastic fixation of the fragments using half frame Hoffmann external fixation. Because of anatomical considerations, the two proximal pins must be inserted laterally in the upper third of the humerus, and the two distal pins in the posterior aspect of the lower third above the olecranon fossa. If the mechanical properties of the bone are poor (due to osteoporosis) more than two pins must be used in each fragment. The advantages of the technique include fast and easy application requiring simple materials; versatility of use for fractures at different levels; possible closed reduction, as in conservative treatments; early rehabilitation of joint function; fast periosteal callus formation; and retrieval of the fixator on an outpatient basis.The reduction and the immobilization of the fracture by osteotaxis are done in emergency. Closed reduction is performed as in conservative treatments. In cases of important muscular interposition, open reduction is possible. Associated internal fixation was required in 18.4% (unstable or articular fractures). A secondary transient radial palsy is observed in 5% of the patients. Intolerance to the external fixation appears in 5.6% of cases, usually consisting of drain age and redness around the pin tracts. A general evaluation of the results gives 73.8% very good results and 93.6% satisfactory results after rehabilitation.