Luc Kerboull

Is the so-called ‘French paradox’ a reality?: LONG-TERM SURVIVAL AND MIGRATION OF THE CHARNLEY-KERBOULL STEM CEMENTED LINE-TO-LINE

We have evaluated the in vivo migration patterns of 164 primary consecutive Charnley-Kerboull total hip replacements which were undertaken in 155 patients. The femoral preparation included removal of diaphyseal cancellous bone to obtain primary rotational stability of the stem before line-to-line cementing. We used the Ein Bild Roentgen Analyse femoral component method to assess the subsidence of the femoral component. At a mean of 17.3 years (15.1 to 18.3) 73 patients were still alive and had not been revised, eight had been revised, 66 had died and eight had been lost to follow-up. The mean subsidence of the entire series was 0.63 mm (0.0 to 1.94). When using a 1.5 mm threshold, only four stems were considered to have subsided. Our study showed that, in most cases, a highly polished double-tapered stem cemented line-to-line does not subside at least up to 18 years after implantation.

Prevention of heterotopic ossification in hip arthroplasty: The influence of the duration of treatment

Abstractu2002A retrospective study has been carried out to assess the effectiveness of indomethacin in preventing heterotopic ossification after total hip arthroplasty, and the effect of using it for different periods of time. One hundred and sixty-eight hips operated on in 1983 were not given indomethacin and acted as a control. One hundred and fifty hips operated on in 1988 were given indomethacin and divided into 3 groups: 42 received indomethacin for 5 days, 49 for 11 days and 59 for 45 days. The results indicate that ossification is significantly reduced in those patients receiving indomethacin for 5 and 11 days, but there was no additional reduction when it was given for 45 days. Treatment should begin on the night of operation and continued for 11 days while the patient remains in hospital.Résuméu2002La révision de 318 patients opérés pour arthroplastie totale à l’hôpital Cochin a permis aux auteurs d’évaluer l’efficacité de l’indométacine pour la prévention de la survenue d’ossifications, et de comparer les résultats obtenus en fonction de la durée de traitement. La réduction de l’incidence des ossifications obtenue avec l’indométacine est très significative, passant de 61,3% dans le groupe non traitéà 26% pour l’ensemble des patients traités, encore plus nette pour les ossifications de haut grade (21,8% dans le groupe non traité contre 4,6% dans le groupe traité). Un seul patient développant des ossifications de degré 3 sur les 150 patients traités. L’analyse des résultats en fonction de la durée de traitement met en évidence une réduction significativement des ossifications pour des traitements de 5 jours (40,5% d’ossifications), une réduction significativement meilleure pour des traitements de 11 jours (20,4% d’ossifications), sans réduction d’incidence supplémentaire pour des traitements plus long. Ces résultats démontrent que la durée optimale de traitement pour une prévention efficace des ossifications péri-prothétiques est de l’ordre de 11 jours, soit en pratique une administration limitée à la durée d’hospitalisation, et débutée le soir ou le lendemain de l’intervention.

Impaction grafting in association with the Charnley-Kerboull cemented femoral component: OPERATIVE TECHNIQUE AND TWO- TO 16-YEAR FOLLOW-UP RESULTS

We describe 129 consecutive revision total hip replacements using a Charnley-Kerboull femoral component of standard length with impaction allografting. The mean follow-up was 8.2 years (2 to 16). Additionally, extramedullary reinforcement was performed using struts of cortical allograft in 49 hips and cerclage wires in 30. There was one intra-operative fracture of the femur but none later. Two femoral components subsided by 5 mm and 8 mm respectively, and were considered to be radiological failures. No further revision of a femoral component was required. The rate of survival of the femoral component at nine years, using radiological failure as the endpoint, was 98%. Our study showed that impaction grafting in association with a Charnley-Kerboull femoral component has a low rate of subsidence. Reconstruction of deficiencies of distal bone with struts of cortical allograft appeared to be an efficient way of preventing postoperative femoral fracture for up to 16 years.

Length of clinically proven cemented hip stems: State of the art or subject to improvement?

PurposeThe purpose of this study was to identify the shortest possible length of an established cemented hip stem in order to reduce stress shielding and optimise its bending behaviour.MethodsTwenty-five prototypes from the same batch (five for each stem length) were included. Lengths resulted from the original length (100xa0%) and four distal shortenings to 94, 88, 83 and 78xa0% of original length. For standardised implantations, synthetic femurs were prepared. Relative movements under axial torque and stem bending under varus–valgus torque applications were investigated consecutively. Analyses of variance (ANOVA) were applied to detect differences between lengths.ResultsThe maximum torque transfer occurred at the level of the lesser trochanter (pu2009<u20090.01). In particular, for the 78xa0% version, relative motion of the stem tip increased significantly compared with all other lengths (pu2009=u20090.02-0.04). Comparable findings were made for mean overall movements. In regards to varus–valgus torque, both the distal tip and the proximal shoulder always bent in the same direction following the femoral deflection. For the 83xa0% version bending of stem’s shoulder was increased compared with the other length (pu2009=u20090.01 - 0.02), whereas tip bending was always comparable (pu2009=u20090.45-0.91).ConclusionsOur data show that the intention to preclinically optimise the mechanical behaviour of cemented stems by modifying their length seems to be a reasonable option. Advantages are decreased inner bone stiffening to reduce stress shielding and a lower cement volume, which is involved in cellular interactions.

Acetabular reinforcement rings associated with allograft for severe acetabular defects

Acetabular revisions with severe bone defects can be challenging procedures. Several grading systems have been set into place to help the surgeon adequately gauge the degree of bone loss within the acetabulum. Internationally innovative research in orthopedics and bio-engineering has helped with progression of successful techniques and rings to re-establish the normal anatomy of the hip. The purpose of this review is to evaluate the outcomes of the different acetabular reinforcement rings in the setting of severe acetabular defects. A successive report of relevant data from the literature of multiple techniques will be provided. The procedures include the cup-cage, the Müller ring, the Ganz Ring, the Kerboull acetabular reinforcement device (KARD), the graft augmentation prosthesis (GAP) ring, and the Burch-Schneider ring. The main focus of this overview is rings only; other devices such as trabecular augments, custom-made cages, or oblong cups are not discussed. Furthermore, a special emphasis on the surgical technique of the KARD is also given. Procedures using these rings are usually associated with bone grafts either bulk or morselized. When considering the available data on these various rings used for reconstruction of the severely damaged acetabulum, the cup-cage, the KARD, and the Burch-Schneider ring appear to be reliable options for more successful long-term outcomes.

Crowe Type IV Developmental Hip Dysplasia: Treatment with Total Hip Arthroplasty. Surgical Technique and 25-Year Follow-up Study

A consecutive series of 118 total hip arthroplasties was performed for Crowe type IV developmental hip dysplasia in 89 patients. The mean age of the patients was 52 years. All procedures were carried out through a transtrochanteric approach by the same surgeon. In all cases, the acetabular component was placed at the level of the true acetabulum. The mean lengthening of the operated limb was 3.8 cm. The average follow-up of the whole series was 16.9 years. At the last follow-up evaluation, 41 patients (48 hips) had died and 7 patients (9 hips) were lost to followup. Forty patients (61 hips) were still alive at a mean follow-up of 22 years. At the time of last follow-up, the mean Merle d’Aubigne hip score was 17 compared with 10.6 preoperatively. The survival rate, with revision for any reason as the endpoint, was 75% at 25-year follow-up.