Purpose of the study: The tibial slope is an important parameter for knee surgery. Tibial slope designates the inclination of the tibial plateaus in the sagittal plane. The presence of a tibial slope and its value is intimately related to the condylotrochleal profile. The importance of tibial slope in knee disease and knee surgery is now universally recognised.

Material and method: We reviewed 140 cases of anterior cruciate ligament (ACL) ligamentoplasty performed at the institute; 25 failures were identified. After analysis of the position of the tunnels, particularly the femoral tunnels, the most documented cause of failure, as well as other factors of failure, we measured the mean tibial slope in all operated patients.

Results: Subjective Lachmann and the IKDC and ARPEGE scores associated with the dynamic study (TELOS) helped understand why knees can become unstable despite good surgical technique.

Discussion: William and Lissner established a mathematical relations between tibial slope and stress forces applied to the ACL. Dejour and Bonnin demonstrated the effect of the tibial slope on anterior subluxation and single leg stance. The tibial slope should thus be considered for all knee procedures. Bonnin demonstrated that an excessive slope can be a factor of plasty failure.

Purpose of the study: This work examined the clinical, radiological, and videoarthroscopic features of partial tears of the anterior cruciate ligament (ACL) and analysed results of ligament plasties.

Material and method: Mean age was 32 years. Patients complained of instability accidents in 70% of cases. The Lachman test was noted soft endpoint to + or ++ in 90%. A palpable click was found in 60% but was considered severe in two cases only. Telos laxity was moderate (about 5 mm) in 80%. Mean time to surgery was relatively short (9 months). Arthroscopic exploration revealed rupture of the anteromedial head of the ACL with preservation of the posterolateral component. There was a meniscal injury in nine knees. Early in our experience we performed a total plasty for nine patients (six using hamstring tendons and three with the patellar tendon). At the present time, we spare the posterolateral head and make a partial plasty of the anteromedial head (11 knees: 3 harvesting a single tendon [gracilis] and eight using the gracilis and the semitendious) associated with lateral reinforcement in five.

Results: Mean follow-up was 30 months; 30% of patients had knee pain. Three knees exhibited a soft endpoint (+) all after a total plasty. There were no cases of quadriceps motion deficit or amyotrophy.

Discussion: The existence of partial tears of the ACL were confirmed in this series. This type of tear corresponds to an objective condition seen arthroscopically and also to precise clinical presentations and biological findings: minor signs of instability with moderate objective anterior instability to the order of 5 mm.

Conclusion: Considering this work and a review of the literature, the diagnosis of partial tears of the ACL could be established from the physical examination and measurements of anterior knee laxity. Reconstruction of a single head provides better results than complete reconstruction which would sacrifice an intact portion of the ACL.

Purpose: Aneurysmal bone cyst is a benign osteodystrophic pseudotumor. It can occur as a primary lesion or develop on a pre-existing lesion. The etiopathogenesis, diagnosis and treatment remain subjects of interest.

Material and methods: For this retrospective analysis, we collected 48 peripheral aneurysmal bone cysts over a 27-year period. Most cysts occurred in children, adolescents, or young adults, with a slight female predominance. Imaging included standard x-rays, computed tomography, and for the more recent cases magnetic resonance imaging (MRI). MRI provided new imaging features increasing diagnostic accuracy. Second readings of histology slides enabled establishment of the correct diagnosis in certain cases but differential diagnosis was established only with benign tumours. Surgical treatment predominated. Other treatments included curettage-filling with cancellous bone, resection, resection-reconstruction,curettage-filling with cement. Adjuvant treatments mainly involved use of calcitonin. Therapeutic abstention with surveillance confirmed the possibility of spontaneous regression after biopsy. Curettage-filling with cancellous bone was performed in 58% of cases, giving an Enneking function score of 95.7%.

Results: We reviewed outcome at mean 7 years follow-up. There were four recurrent cysts and the mean global Enneking score was 95%. Our series showed the several methods can be used for the treatment of aneurysmal bone cysts, the indication taking into consideration the patient’s age, the location of the lesion and is progression. We propose a therapeutic schema. The role of calcitonin remains to be determined.

Conclusion: The diagnosis of bone cysts requires a close collaboration between the surgeon, the radiologist, and the pathologist. The indication for surgery must be made case by case to achieve cure without sequelae.

Purpose: Surgery is generally proposed for the treatment of giant-cell bone tumours but other options are discussed. The problem is to decide between curettagefilling and enucleation, using or not local adjuvant treatment with curettage, and filling with an autograft, an allograft, or cement. The purpose of this work was to provide a new perspective to the treatment of giant-cell tumours based on the tumour pathophysiology and calcitonin infiltration.

Material and methods: We report 25 cases of benign giant-cell tumours treated by calcitonin. Mean patient age was 31 years. Female gender clearly predominated (75%). All of the tumours were located at the extremity of long bones. We grouped the tumours as quiescent benign tumours, and active or aggressive tumours according to the Enneking classification. Our treatment protocol included four stages after histological confirmation of the diagnosis on the biopsy specimen. The first stage was aggressive curettage, followed by intramuscular injection of calcitonin until cutaneous healing. The third stage involved daily washing of the tumour cavity with saline solution for one month. The final stage lasted two months with intramuscular injections of calcitonin.

Results: We analysed outcome at mean three years (range 2 – 20 years). Progressive filling of the tumour cavity was observed in the majority of patients starting with the first month of treatment even for the aggressive forms where tumour resection was tempting. Using the Enneking scale, our rates were near 90%, largely above the rates obtained with other conventional techniques. There were no complications. We did however have eight cases of recurrence including three which were treated again with the same protocol with good outcome.

Discussion and conclusion: Giant-cell bone tumours are clearly hormone sensitive. Calcitonin would appear to arrest the osteolytic process by attacking the osteoclast-like cell which bears calcitonin-receptors. Daily washing of the tumour cavity is designed to modify the microenvironment and eliminate tumour growth factors and cytokines expressed by giant-cells. More detailed studies of the cell membrane might reveal an explanation of certain calcitonin escape phenomena which are the cause of more or less long-term recurrence.

Purpose: Osteoid osteoma is a benign small-sized painful osteoblastic tumour usually observed in young subjects. The purpose of this work was to study the epidemiological, clinical, radiological, and histological features, focusing on clinical course after treatment and differences by location.

Material and methods: We report a retrospective series of 56 osteoid osteomas located in limbs treated over a 25-year period from 1976 to 2001. The tumour involved the femur (n=21), the tibia (n=14), the hand (n=8), the foot (n=7), and the olecranon, the lateral humeral condyle, the humeral neck, and the acetabulum (n=1 each). Pain was the pain symptom, found in all patients. The aspirin test was positive in 82%. The joint locations led to an arthropathy in 87%. The typical nidus aspect was found on 78.5% of the plain x-rays. Computed tomography was performed in 25 patients and scintigraphy in 10. Magnetic resonance imaging was performed in 4. Surgical treatment consisted in en bloc resection (n=48), intra-lesions curettage (n=6), computed tomography-guided percutaneous resection (n=2). Mechanical protection was obtained with a plaster cast (n=21) and osteosynthesis material (n=7). A bone graft was used in 22 patients. Pathology confirmed osteoid osteoma in all patients. Lymphocyte plasma cell infiltrations were observed in seven of the articular localisations.

Results: Mean follow-up was 5 years. Complete pain relief was achieved after a single resection in 53 patients and after re-operation of a second resection in the others. For the joint localisations, complete joint movement was recovered in three-quarters of the patients. Postoperative x-rays were performed in all cases. The main early complications were iatrogenic fracture (9%), mainly in patients with a tibial tumour. Late complications included osteoarthritis for the acetabular tumour and two cases of talal degeneration.

Conclusion: Osteoid osteoma is an uncommon tumour general easy to recognise. Atypical clinical and radiological presentations are rare. Computed tomography is the key to diagnosis and provides important therapeutic information.

Purpose: Leg fractures are a daily problem in orthopaedic surgery. The frequency has increased due to the growing number of traffic accidents. Social impact is important because the injured population is young and active. The purpose of this work was to analyse anatomic and functional results obtained in a series of patients and to identify indications and limitations of centro-medullary alignment nailing for the treatment of leg fractures.

Material and methods: This series included 207 leg fractures treated with this method at the Kassab Orthopaedic Institute. There were 174 men and 33 women, mean age 35 years (15–75). Male predominance was considerable (84%). Centromedullary nailing was completed with a plaster cast and weight bearing after a mean four to five weeks with a Sarmiento walking case until bone healing.

Results: Results were analysed at mean 12 months follow-up (4 months–18 years). Bone healing was achieved in 99% of the cases within a mean time of 15.3 weeks (6–66 weeks). There were 16 cases with a deformed callus (7.8%) predominantly in varus (n=10) and thirteen secondary dislocations (6.3%). This was significantly more frequent for fractures of the proximal third in comparison with the mid third, or comminutive bifocal fractures, and when weight bearing occurred before the fourth week.

Discussion: The functional outcome showed pain at walking in 15% of the patients. Walking distance was unlimited in three-quarters of the patients and joint motion was good. Alignment nailing is a reliable easy to use technique providing satisfactory results for the treatment of simple fractures of the mid third of the leg. Fractures of the upper and lower third, as well as bifocal and comminutive fractures require a locked nail to neutralise the risk of secondary displacement and misalignment callus.