Tibial tunnel enlargement after anterior cruciate ligament reconstruction by autogenous bone-patellar tendon-bone graft.

This retrospective study was designed to evaluate changes in the diameter of the tibial tunnel over time following the reconstruction of the anterior cruciate ligament (ACL) with a bone-patellar tendon-bone autograft in 44 patients. The changes in the geometry of the bone tunnels were measured radiographically during the immediate postoperative period and at time intervals between 3 and 36 months after surgery. The dimensions at 1 year were correlated with the 1-year clinical results. The distance between the sclerotic margins of the tibial tunnel was measured at the distal tunnel exit on the medial tibial cortex, in the middle of the tunnel, and proximally at the level of the joint line. The dimensions were calculated by using a magnification factor determined by reference to the interference screw of known diameter located within the tunnel. The position of the centre of the tibial tunnel with regard to Blumensaat's line was also measured. The average tunnel diameter at the proximal tibial exit increased from 12 +/- 1.9 mm (mean +/- standard deviation) postoperatively to 14 +/- 2.2 mm at 3 months. The average proximal tunnel diameter did not significantly change from 3 months to 2 years, and then decreased to 13 +/- 2.4 mm at 3 years. At 1 year, most of the patterns of osteolysis were of the cone type (57%), followed by the cavity type (40%) and line type (3%). The degree of osteolysis was not related to the tibial tunnel position with respect to Blumensaat's line. There was no correlation between the changes in tunnel diameter and either the IKDC score or the residual joint laxity measured by a KT-100 arthrometer. The aetiology of tunnel enlargement is currently unknown. Possible factors responsible for bone resorption include micromotion of the graft relative to the tunnel wall, leading to an inflammatory response in the tunnel, or stress shielding of the tunnel wall proximal to the interference screw.

[Idiopathic massive osteolysis of the femur. Syndrome called Gorham-Stout syndrome]. / Ostéolyse massive idiopathique du fémur. Syndrome dit de Gorham-Stout.

A case of massive osteolysis (disappearing bone disease, phantom bone, Gorham's massive osteolysis) was observed in a young african man with two lesions of the femur. This is a very rare syndrome characterized by an acute spontaneous resorption of bone, without any sign of malignant or infectious disorder. The lesion may develop in any part of the skeleton, with extensive bone loss, but is benign. Bone is replaced by haemangiomatous tissue. The diagnosis lead on the association of clinical, radiological and histological signs. The pathogenesis is still unknown and the treatment remains controversial. Osteolysis stops after a few years, but this is unpredictable; in our case, we have proposed prosthetic replacement, associated with bone grafting and irradiation.

[Single-compartment "Lotus" type knee prosthesis in the treatment of lateralized gonarthrosis: results in 135 cases with a mean follow-up of 4.6 years]. / Prothèses unicompartimentaires du genou type "Lotus" dans le traitement des gonarthroses latéralisées: résultats de 135 cas avec un recul moyen de 4.6 ans.

Controversy exists on the indications and results of unicompartmental arthroplasty in the treatment of unicompartmental knee arthritis. This led us to study 135 Lotus prostheses implanted from December 1974 to February 1990. The follow-up lower than 1 year for 14 knees (11 were lost to follow-up, 3 were reoperated). One hundred and twenty-one knees were clinically evaluated with an average follow-up of 4 years and 6 months using both the GUEPAR and the Knee society grading systems. 71.9 per cent of the knees were rated good, 28.1 per cent were rated poor (19 per cent were revised). This important rate of poor results was due to poor technique (11 knees) and to poor indications (7 knees). Polyethylene wear, and radiolucent line especially when it was evolutive were significantly correlated to failures and poor results. Failures were seldom unifactorial but often multifactorial. Over or undercorrection of coronal deformity, absence or lengthening of the anterior cruciate ligament were the failure factors most often found. Decrease of good results with time, and polyethylene wear of unicompartmental arthroplasties are factors which lead us to carefully consider osteotomy for patients under 65 years. The failure rate may decrease with good indications and a better technique allowing unicompartmental arthroplasty to be a good choice for unicompartmental arthritis.

[Knee prosthesis in 1990. Apropos of a 15 years' experience]. / Les prothèses de genou en 1990. A propos d'une expérience de 15 ans.

Knee prostheses have been greatly refined over the past ten years. A range of prostheses with various designs are currently used. On the basis of their 15-year experience, the authors assess the role of the various prostheses. Among partial prostheses, the femoropatellar prosthesed have a restricted place and are reserved for isolate degenerative diseases of the femoropatellar joint without femorotibial involvement: 34 such prostheses have been used by the authors and the department of professor J.H. Aubriot in Caen. About 75% of the results are satisfactory, with a follow-up in time of more than 8 years in 6 of these cases. Single-compartment prostheses are used in degenerative disease on an angular deviation, condylar necrosis or post-traumatic lesions, as far as one compartment only is affected. The authors have inserted 115 "Lotus" uni-compartment prostheses at Saint-Louis hospital. 75.6% of these have very good or good results maintained in time, as 72% of the 32 prostheses still produce satisfactory results after 5 years or more. The greatest progress was made above all for total prostheses replacing all the compartments of the knee. Hinge prostheses now have only rare indications as first-intention prostheses due to the immediate vital risks and to the high percentage of suppuration and long-term loosening. Sliding prostheses have taken an increasingly dominant place. The authors used Insall's total condylar prostheses, which do not preserve the posterior cruciate ligament, until 1983. 45 prostheses were followed up for 1 to 10 years, showing 71% of very good or good results.(ABSTRACT TRUNCATED AT 250 WORDS)