Purpose: The posterior cruciate ligament (PCL) has two strands, an anterolateral strand (AL) and a posteromedial strand (PM). Its femoral insertion fans out over 3 cm and cannot be replaced by a unique transplant during surgical reconstruction. The purpose of this study was to define the anatomic centre of the femoral insertion of each stand in order to identify precise and reproducible landmarks for the bone tunnels (one for each strand) used to fix the transplants during reconstruction of the PCL.

Material and methods: A metallic landmark was placed on the centre of the femoral insertion of the two PCL strands in ten cadaver knees. The Metros software package was used to analyse the digitalised radiograms of each knee to determine the position of the strands on the medial condyle. Intra- and inter-observer variability was determined.

Results: The AL strand was situated 31.6 + 2.45% (47.2 + 6.02% for the PM strand) from the anterior border of the notch or 41.18 + 2.73% (54.46 + 5.07% for the PM) from the anterior border of the medial condyle relative to the Blumensaat line and 16.12 + 4.45% (33.68 + 7.2 for the PM) from the apex of the notch.

Discussion: Clinical and objective results of reconstruction depend on the ideal, basically femoral, position of the PCL insertions. Intraoperative identification of the ideal point for the femoral insertion can be improved with measurements made on cadaver knees. The values observed in the present study are reproducible. Presented in the form of percentages of length limiting the errors related to patient morphotype can be integrated into navigation systems.

Purpose: There are three main causes of failure after valgisation osteotomy of the tibia requiring repeated osteotomies: insufficient valgus, excessive valgus, or loss of the valisation correction after a variable delay. The purpose of this study was to evaluate outcome after repeated oseotomies performed in relatively young patients or too active to propose arthroplasty. The technical problems were different for each aetiology.

Material and methods: The series included 47 knees operated on between 1974 and 1998 after a first osteotomy performed at a mean age of 46 years. Mean delay between the two operations was five years (1 to 12). A medial closure osteotomy had been performed at the first operation in 34 cases and a lateral opening osteotomy in 13. For the 19 knees with valgus, the second osteotomy was a medial closure in 14 and a lateral opening in five. A repeat valgisation was performed in 28 cases, 18 by lateral closure, one by medial opening and nine by curviplanar osteotomy. The IKS score was determined to assess function. The femoraotibial axes (HKA angle) were determined on full stance views. The Ahl-back osteoarthritis grading was used. For 17 patients who had undergone operations in other institutions, exact measurements were not always available concerning the preoperative status and the initial correction.

Results: The overall IKS score for function improved in 87% of the cases with a mean follow-up of five years. The IKS knee score improved from 73 to 89 points and the IKS function score from 65 to 81 points. For the 19 over-corrections, the mean HKA angle was changed from 190° to 184°. For the 28 under-corrections, the mean HKA angle was changed from 173° to 182°. The tibial tilt remained unchanged at 7° as did lateral gapping at 3°. Delay to consolidation was a mean 96 days.

Discussion: Revision osteotomies performed for correction defects should be distinguished. For these procedures, it would be logical to expect a good result if a 3 to 5 degree valgus is achieved. Revisions after a long period (33 cases) are different; required for wear, these cases correspond to progressive loss of the initial osteotomy effect. These patients are often candidates for prosthesis if seen after 70 years. Good results can however be obtained with a second osteotomy irrespective of the initial technique. We prefer reoperating with medial opening after initial lateral closure.

Purpose: Several techniques have been described for the treatment of unstable fractures of the upper humerus. None appear to be appropriate for subtuberosity fractures, associated or not with a fracture of the trochiter or impacted valgus cephalotuberosity fractures, allowing a stable fixation with anatomic reduction while preserving blood supply to the bone fragments. For the last year, we have studied prospectively a percutaneous minimally invasive technique for this type of fracture. Our preliminary results are analysed here.

Material and methods: We used this technique for 12 patients aged 30 to 87 years with five displaced subtuberosity fractures, six subtuberosity fractures with a trochiter fracture and one impacted valgus cephalotuberosity fracture. Excepting the cephalotuberosity fracture, the joint fragment of the head was reduced by external manipulation under image amplifier guidance. Fixation was achieved with two 25/10 threaded pins inserted percutaneously in retrograde fashio from the anterolateral cortical to the humeral shaft. For eight cases, a third pin was inserted percutaneously from the trochiter to the medial cortical of the humerus. When percutaneous reduction of the trochiter was impossible (three cases) and for the cephalotuberosity fracture, we used a minimal transdeltoid lateral incision to reduce the trochiter and achieve reduction.

Results: Reduction was very satisfactory in all cases. There was one superficial infection that required pin withdrawal at three weeks leading to the only secondary displacement that was minimal and tolerable. We removed the pins after a mean two months. There were no nonunions. Seven patients have a follow-up greater than six months and exhibited a Constant score of 87% (71% to 100%).

Discussion: This techniques has provided very satisfactory results for rapid and stable fixation of the cephalic fragment without loss of blood supply and with a material easy to remove.

Conclusion: These early results are very encouraging and incite us to pursue this technique and analyse long-term results.

We have measured anterior and posterior displacement in 563 normal knees and 487 knees with chronic deficiency of the anterior cruciate ligament (ACL). We performed stress radiography using a simple apparatus which maintained the knee at 20° of flexion while a 9 kg load was applied. There was no significant difference in posterior translation dependent on the condition of the ACL. Measurement of anterior translation in the medial compartment proved to be more reliable than in the lateral compartment for the diagnosis of rupture of the ACL, with better specificity, sensitivity and predictive values.

We have classified anterior laxity based on the differential anterior translation of the medial compartment and identified four grades in each of which we can further distinguish four subgrades for laxity of the lateral compartment. Within each of these subgroups, either internal or external rotation may dominate and sometimes there is a major translation of both compartments.

Radiological evaluation of displacement of the knee in 20° of flexion provides conclusive evidence of rupture of the ACL. A detailed study of pathological displacement is the basis for a classification of laxity. It is then possible to decide for each type of laxity, the surgical treatment which is specifically adapted to the lesion, and to define a reference value for judging outcome.