Case Report: Atypical acute compartment syndrome of the forearm in a child following minor trauma with consecutive osteomyelitis.

Introduction: Forearm compartment syndrome (CS) in children is above all a clinical diagnosis whose main cause is traumatic. However, rarer causes such as infection can alter its clinical presentation. Clinical case: An 8-year-old boy has been seen in the emergency department complaining of severe forearm pain under a splint in a mild traumatic context. The previous radiological imaging examination three days before had not revealed any fractures. On admission, he presented with major signs of skin inflammation, loss of mobility, paresthesia and a significant biological inflammatory syndrome. The acute CS diagnosis has been made and was treated, but its atypical presentation raised a series of etiological hypotheses, in particular infectious, even if it remains rare. Complementary imaging examinations confirmed the presence of osteomyelitis of the distal radius as well as an occult Salter-Harris II fracture. Discussion: Beyond the classic "five P's of CS" -pain, paresthesia, paralysis, pallor and pulselessness-, CS's clinical presentations are multiple, especially in pediatric patients. In children, severe pain and increasing analgesic requirement must be indicators of a CS. We hypothesize that this patient sustained a nondisplaced Salter-Harris II fracture with a hematoma colonized by hematogenous osteomyelitis explaining its initial clinical presentation. Conclusion: Hematogenous osteomyelitis complicated by CS is rare and may be accompanied by a traumatic history. It's atypical presentation in pediatric patients requires vigilance and prompt diagnosis given the disastrous and irreversible complications.

[Management of the meniscal lesion]. / Prise en charge de la lésion méniscale.

About 1,5 million arthroscopies are each year performed in the world, 50 % for meniscal affections. The menisci participate in the femoro-tibial load transmission and in the joint shock absorption; they contribute to the knee stability and play a role in the joint lubrication. The menisci are therefore important structures, and, in the case of a lesion, surgical abstention or repair should be favoured. When a meniscectomy has to be performed, it should be economical, preserving the meniscal wall. Meniscectomy is contra-indicated in the child and in the case of knee osteoarthrosis. Meniscal healing is compromised if the knee is unstable. If after total meniscectomy a patient presents symptomatic early osteoarthrosis, without marked loss of alignment, meniscal allografting is a therapeutic option, especially at the lateral compartment.

[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.

[Reconstruction of the knee anterior cruciate ligament: single or double bundle?]. / Reconstruction du ligament croisé antérieur du genou: simple ou double faisceau?

Anatomical and biomechanical studies have shown that the anterior cruciate ligament (ACL) consists of two distinct bundles, the anteromedial (AM) and posterolateral. Each bundle has its specific role during the motion of the knee. ACL reconstruction techniques have focused on the restauration of the anteroposterior stability by substituting the more isometric AM bundle. Although these ligamentoplasties provide overall good results, in the last ten years double-bundle ACL reconstruction techniques have been developed, to better replicate the ligament anatomy. Despite the growing number of published studies, including randomized controlled trials comparing single bundle and double bundle reconstructions, there is still a lack of evidence of any superiority of the double-bundle technique. Furthermore, many series are criticized for their poor assessement of rotational stability, using most of the time subjective pivot shift clinical testing. Among the methods available to measure tibial rotation, 3-D optoelectronic evaluation is an attractive tool and has been used in some studies reporting rotational mesurements after ACL single-bundle reconstruction. Our Department of Orthopaedics and Traumatology has been using double-bundle techniques for a few years. We conducted a preliminary prospective randomized study, in order to compare single and double-bundle techniques by clinical and optoelectronic evaluations.

[Changes in knee kinematics and quadriceps and hamstrings moment arms after high valgus and varus tibial "dome" osteotomy: An in vitro study]. / Modifications de la cinématique du genou et des bras de levier du quadriceps et des ischio-jambiers après ostéotomie tibiale haute "curviplane" de valgisation ou de varisation: étude in vitro.

PURPOSE OF THE STUDY: Analysis of the correction or over-correction of high valgus and varus tibial osteotomies is generally limited to the frontal plane. Most likely however, the deformation observed radiographically in the frontal plane is simply a one-dimensional expression of a more complex three-dimensional deformation. This might be one of the causes for certain failures after surgery and recurrent problems which are difficult to solve. We proposed using 3D electrogoniometric to measure of the effect of a "dome" osteotomy on patellar and femoro-tibial kinematics and the changes in the moment arms of the knee muscles. MATERIAL AND METHODS: We used five lower limbs harvested from non-fixed cadavers. A "dome" osteotomy was stabilized by external fixation. Three-dimensional analysis of the femoro-tibial and femoro-patellar kinematics was performed using two electrogoniometers with six degrees of freedom. Changes in the lengths of the hamstrings and quadriceps was measured using four LVDT linear variable differential transformers. The muscles lever arms were measured with the tendon excursion method. RESULTS: At 90 degrees flexion, varus osteotomy induced internal rotation while valgus osteotomy induced the opposite effect. Beyond 40 degrees flexion, there was a clear internal rotation of the patella for varus and neutral corrections. Valgus corrections however induced external rotation. The peak lever arm of the quadriceps increased with valgus, while the angle of the peak was higher for varus correction. Valgus appeared to increase the lever arm of the semitendinous. DISCUSSION: Our study demonstrated that the effect of tibial osteotomy is not limited to the frontal plane. Tibial rotations are observed systematically for all corrections in the frontal plane. Varus correction tends to create internal rotation while valgus correction tends to have the opposite effect. Axial correction also affects patellar kinematics. Interanal rotation is induced by varus correction and external rotation by valgus correction. This patellar rotation could result from tibial rotations induced by the different corrections. The loss of the parallelism between the patellar crest and the trochlear groove could produce changes in femoropatellar surface contact and pressure, potentially leading to pain or cartilage degeneration. The maximal value of the quadriceps moment arm appears to increase with valgus. The efficacy of the quadriceps could thus be improved with valgus, potentially increasing extension force. Valgus increases the moment arm, improving limb flexion, while varus correction has the opposite effect. This could explain a loss in flexion amplitude in patients with varus or who underwent varus osteotomy. Tibial osteotomy is designed to correct the deviation solely in the frontal plane but also has effects in all three planes. Further 3D analyses of the morphology and physiology of the knee joint would be needed to better understand the physiological and pathological processes involved.

In vitro biomechanical study of femoral torsion disorders: effect on moment arms of thigh muscles.

BACKGROUND: Lower limb torsion disorders have been considered as a factor inducing gonarthrosis and the three-dimensional effect of the surgical correction is not well reported yet. This paper reports an in vitro study aiming at quantifying the relationships between experimental femoral torsion disorders and moment arms of thigh muscles. METHODS: Five unembalmed lower limbs were used and fixed on an experimental jig. Muscles were loaded and 6 Linear Variable Differential Transformers were used to measure tendon excursions. Experimental osteotomies were performed to simulate torsions by steps of 6° up to 18°. Moment arms of the main thigh muscles were estimated by the tendon excursion method during knee flexion. FINDINGS: Moment arms of the tensor of fascia latae, the gracilis and the semitendinosus were significantly influenced by experimental conditions while the rectus femoris, the biceps femoris and the semimembranosus did not show modifications. Medial femoral torsion decreased the moment arm of both the gracilis and the semimembranosus. Opposite changes were observed during lateral femoral torsion. The moment arm of the tensor of fascia latae decreased significantly after 30° of knee flexion for 18° of medial femoral torsion. INTERPRETATION: Our results showed that medial and lateral femoral torsion disorders induced alterations of the moment arms of the muscles located medially to the knee joint when applied in aligned lower limbs. These results highlight a potential clinical relevance of the effect of femoral torsion alterations on moment arms of muscles of the thigh which may be related, with knee kinematics modifications, to the development of long-term knee disease.

In vitro biomechanical study of femoral torsion disorders: effect on femoro-tibial kinematics.

BACKGROUND: Gonarthrosis is a degenerative disease mainly found in elderly persons. Frontal plane deviations are known to induce lateral and medial gonarthrosis. Nevertheless, patients suffer from gonarthrosis without frontal deviations. Lower limb torsions disorders have been considered as a factor inducing lateral and medial gonarthrosis. This paper reports an in vitro study aiming at quantifying the relationships between experimental femoral torsion disorders and femoro-tibial kinematics. METHODS: Five fresh-frozen lower limbs were used. Specimens were fixed on an experimental jig and muscles were loaded. A six-degree-of-freedom Instrumented Spatial Linkage was used to measure femoro-tibial kinematics. Experimental femoral osteotomies were performed to simulate various degrees of medial and lateral torsion. Internal tibial rotation, abduction/adduction and proximo-distal, medio-lateral and antero-posterior translations were measured during knee flexion. FINDINGS: Internal tibial rotation and abduction/adduction were significantly influenced (P<0.001) by femoral torsion disorder conditions. Medial femoral torsion increased tibial adduction and decreased internal rotation during knee flexion. Opposite changes were observed during lateral femoral torsion. Concerning translations, medial femoral torsion induced a significant (P<0.05) decrease of medial translation and inversely for lateral femoral torsion. No interactions between femoral torsion disorders and range of motion were observed. INTERPRETATION: Our results showed that medial and lateral femoral torsion disorders induced alterations of femoro-tibial kinematics when applied in normally aligned lower limbs. These results highlight a potential clinical relevance of the effect of femoral torsion alterations on knee kinematics that may be related to the development of long-term knee disease.