Xavier Flecher

A 12-28-year followup study of closing wedge high tibial osteotomy.

Current indications for high tibial osteotomy (HTO) are controversial although several risk factors have been associated with HTO survival. We ascertained the influence of preoperative variables in a consecutive series of patients who had closing wedge HTO at a minimum of 12 year followup (mean 18-year, range 12 to 28 years). Three hundred one of an initial 372 high tibial osteotomies (313 patients) were included (81% followup); 71 knees were eliminated because patients died (30 knees) or were lost to followup (41 knees). The mean age was 42 years (range, 15-76 years), 194 were men and 119 were women. The osteotomy was fixed by a Blount staple and an AO half-tube plate with three screws. Forty-three knees (14%) in 39 patients were revised for progression of osteoarthritis at an average of 102 months. Survival was 85% at 20 years with revision as the endpoint. Knee function was considered satisfactory by 77% of patients. At final followup, ½ of the knees showed radiographic signs of medial osteoarthritis. The most important risk factors predicting revision were age greater than 50 years and a preoperative arthritis Ahlback grade of 3 or more. Level of Evidence: Level IV, therapeutic study (case series). See the Guidelines for Authors for a complete description of levels of evidence.

Patellofemoral arthroplasty: an update.

The rationale for presenting this updated study is to report long-term clinical and survival results of patellofemoral arthroplasty and to ascertain whether the preoperative diagnosis influenced outcomes and therefore indications. We retrospectively updated a previous evaluation of 66 patients who had unilateral patellofemoral arthroplasty between 1972 and 1990. The mean age of the patients at the initial surgery was 57 years (range, 21-82 years). The patients had an average followup of 16.2 years (range, 12-20 years). Preoperative diagnosis included instability, fracture, and primary arthritis. Revision surgery was done in 14 patients for femorotibial osteoarthritis, in 11 for loosening, and in four for stiffness. Survivorship was 58% at 16 years. The knee function score improved from 40 points preoperatively to 81 points at last followup. The best results were in patients with preoperative instability and corrected alignment of the extensor mechanism. Stiffness occurred only in those patients with osteoarthritis from previous fracture. Progressive degeneration of the tibiofemoral joint was noted mainly in the primary osteoarthritis etiologic group. This long-term evaluation of patellofemoral arthroplasty showed the importance of patient selection while excluding knees with significant frontal tibiofemoral malalignment. Level of Evidence: Therapeutic study, Level IV-1 (case series). See the Guidelines for Authors for a complete description of levels of evidence.

Anatomy of the Dysplastic Hip and Consequences for Total Hip Arthroplasty

Total hip arthroplasty in dysplastic hips is challenging because of the modified anatomy of the proximal femur and acetabulum. We studied three-dimensional anatomic parameters in 247 dysplastic hips from 218 adult patients using radiographs and computed tomography, and analyzed the consequences for total hip arthroplasty. A cohort of 310 primary osteoarthritic hips was used as a control group. According to the classification of Crowe et al, 78 of the dislocated hips were graded Class I, 26 as Class II, 20 as Class III or IV, and 169 dysplastic hips had no subluxation. Compared with primary osteoarthritis, the intramedullary femoral canal had reduced mediolateral and anteroposterior dimensions. With high grade subluxations the femoral neck shaft angle decreased but with low grades, especially in Class II, the neck shaft angle increased. The proximal femur had more anteversion with individual variations ranging from 1° to 80°. The true acetabulum had a reduced anteroposterior diameter. The large individual morphologic variability across all levels of dysplastic hips suggests the femoral prosthesis cannot be chosen on the basis of the severity of the subluxation alone.

Three-dimensional anatomy of the hip in osteoarthritis after developmental dysplasia

Using radiography and computer tomography (CT) we studied the morphology of 83 hips in 69 Caucasian adults with osteoarthritis secondary to developmental dysplasia of the hip (DDH). A previously published series of 310 hips with primary osteoarthritis was used as a control group. According to the Crowe classification, 33 of the dysplastic hips were graded as class I, 27 as class II and 23 as class III or class IV. The intramedullary femoral canal had reduced mediolateral and anteroposterior dimensions in all groups compared with the control group. Only in Crowe class II hips was the femoral neck-shaft angle increased. The proximal femur had more anteversion in all the developmental dysplasia of the hip groups, ranging from 2 degrees to 80 degrees. Templated measurement of acetabular dimensions for plain radiography closely matched measurements taken by CT. The results of our study confirm the observations previously confined to the Japanese population.

Evaluation of the hip center in total hip arthroplasty for old developmental dysplasia.

We describe the problems with positioning the hip center according to the severity of dislocation in 97 cementless total hip arthroplasty for developmental dysplasia of the hip. The mean location of the hip center from the interteardrop was 30.4 +/- 8.7 mm horizontally and 23.4 +/- 5.4 mm vertically. The presence of a limp correlated with a superior placement of the cup. Four cups were revised, 2 of which with a significant high hip center. The survival rate of the acetabular component was 95% at 12 years. Craniopodal repositioning was easy in class 1. In class 2, the cup was the largest. In class 3, the greatest variations of the hip center were found. In class 4, the smallest implants were necessary for positioning in the true acetabulum.

Tiges fémorales sur mesure non cimentées pour séquelle de dysplasie et luxation congénitale de hanche

Resume L’etude comportait 257 cas de dysplasie et luxation congenitale de hanche, traites par tige sur mesure, etudies avec un recul moyen de 82 mois (43 a 162 mois). L’âge moyen etait de 55 ans. Le bilan radiotomodensitometrique preoperatoire a etudie : le stade de la luxation, l’inegalite de longueur, l’angle d’anteversion, le diametre de l’acetabulum. La cupule etait non cimentee avec crochet dans le trou obturateur pour guider l’implantation dans le paleo-acetabulum. La cavite endomedullaire du femur etait preparee a l’aide d’une râpe mousse a la forme de la prothese definitive et le col prothetique adapte pour chaque cas au bras de levier et a l’anteversion. Il y avait 174 dysplasies et 83 luxations. L’allongement moyen a realiser etait de 39 mm. L’angle d’helitorsion moyen etait de 28 ± 16,6 et le diametre anteroposterieur de l’acetabulum de 51 mm. Le score de Postel Merle d’Aubigne est passe de 10,4 points en preoperatoire a 16,7 points au recul. L’analyse radiographique postoperatoire a montre une osteo-integration dans 88%, une osteolyse dans 5% et un enfoncement de tige dans 1 cas. Dix hanches (3,9%) ont ete reprises. La survie etait de 95,6% (IC = 94,6 a 97,6) a 13 ans. Cette etude confirme les modifications anatomiques rencontrees dans les sequelles de dysplasie sans correlation entre l’importance de la luxation et le degre d’anteversion, difficiles a evaluer sans tomodensitometrie preoperatoire. La partie intra-medullaire de la tige non cimentee doit etre adaptee aux dimensions du canal femoral et le col prothetique adapte au bras de levier et a l’anteversion.

Three-dimensional custom-designed cementless femoral stem for osteoarthritis secondary to congenital dislocation of the hip

A clinical and radiological study was conducted on 97 total hip replacements performed for congenital hip dislocation in 79 patients between 1989 and 1998 using a three-dimensional custom-made cementless stem. The mean age at operation was 48 years (17 to 72) and the mean follow-up was for 123 months (83 to 182). According to the Crowe classification, there were 37 class I, 28 class II, 13 class III and 19 class IV hips. The mean leg lengthening was 25 mm (5 to 58), the mean pre-operative femoral anteversion was 38.6 degrees (2 degrees to 86 degrees ) and the mean correction in the prosthetic neck was -23.6 degrees (-71 degrees to 13 degrees ). The mean Harris hip score improved from 58 (15 to 84) to 93 (40 to 100) points. A revision was required in six hips (6.2%). The overall survival rate was 89.5% (95% confidence interval 89.2 to 89.8) at 13 years when two hips were at risk. This custom-made cementless femoral component, which can be accommodated in the abnormal proximal femur and will correct the anteversion and frontal offset, provided good results without recourse to proximal femoral corrective osteotomy.

Reprise des descellements acétabulaires aseptiques par cupule non cimentée, vissée et allogreffe morcelée impactée

Resume La chirurgie de reconstruction acetabulaire dans les reprises de protheses totales de hanches, implique de restaurer le capital osseux, d’assurer une stabilite primaire satisfaisante et de restaurer le centre de rotation anatomique de la hanche. Le but de notre etude etait d’evaluer les resultats d’une technique de reconstruction acetabulaire associant des allogreffes morcelees impactees et anneau de soutien non cimente dans les reprises de prothese totale de hanche avec perte de substances acetabulaires de type III de l’AAOS. Cette serie retrospective homogene comporte 34 reconstructions acetabulaires pour descellement acetabulaire aseptique avec perte de substance osseuse de type III de l’AAOS associant un anneau de soutien non-cimente et une allogreffe morcelee impactee. L’analyse radiologique postoperatoire au recul portait sur la position de l’implant acetabulaire, sa stabilite, la restauration du centre de rotation de la hanche et l’integration de la greffe. Le recul moyen etait de 6,6 ans (3-13 ans). Sept patients ont presente une complication necessitant une reintervention, dont 2 avec changement d’implant acetabulaire en raison d’une infection. La survie selon Kaplan-Meier etait de 91,3 % a 10 ans. Le score de Harris moyen passait de 53 points en preoperatoire a 94 points au recul. Sur le plan radiologique aucune migration de cupule n’a ete observee, l’integration de la greffe etait bonne dans 100 % des cas et la lateralisation de la hanche etait restauree dans 66 % des cas. L’association d’une technique cumulant les avantages d’une cupule « press-fit » non cimentee et d’un anneau de recentrage a des greffes morcelees impactees a permis de repondre aux objectifs fixes dans notre etude : reconstruction osseuse, stabilite de la fixation et recentrage de la hanche dans les revisions acetabulaires avec perte de substance de type III de l’AAOS.

Lower limb length and offset in total hip arthroplasty.

Restoration of normal hip biomechanics is a key goal of total hip arthroplasty (THA) and favorably affects functional recovery. Furthermore, a major concern for both the surgeon and the patient is preservation or restoration of limb length equality, which must be achieved without compromising the stability of the prosthesis. Here, definitions are given for anatomic and functional limb length discrepancies and for femoral and hip offset, determined taking anteversion into account. Data on the influence of operated-limb length and offset on patient satisfaction, hip function, and prosthesis survival after THA are reviewed. Errors may adversely impact function, quality of life, and prosthetic survival and may also generate conflicts between the surgeon and patient. Surgeons rely on two- or three-dimensional preoperative templating and on intraoperative landmarks to manage offset and length. Accuracy can be improved by using computer-assisted planning or surgery and the more recently introduced EOS imaging system. The prosthetics armamentarium now includes varus-aligned and lateralized implants, as well as implants with modular or custom-made necks, which allow restoration of the normal hip geometry, most notably in patients with coxa vara or coxa valga. Femoral anteversion must also receive careful attention. The most common errors are limb lengthening and a decrease in hip offset. When symptoms are caused by an error in length and/or offset, revision arthroplasty may deserve consideration.

Le corps adipeux infra-patellaire : carrefour antérieur du genou

Infrapatellar fat pad: anterior crossroads of the knee The infrapatellar fat pad or Hoffa’s fat pad is a cylindrical extrasynovial collection of fat located in the infrapatellar region. Anatomical, biomechanical and imaging data show that the infrapatellar fat pad constitutes a true crossroads between patella, femur and tibia and helps in understanding if not describing regional pathology. Intrinsic lesions (with abnormal signal on MRI) such as hoffitis, anterolateral impingement, plica syndrome, post-arthroscopic changes, trauma, patellar dislocation and extrasynovial tumors are less frequent. On the other hand, extrinsic lesions are more frequent and may affect the synovium, patellar ligament, vascular structures, and bursae. Mucoid and parameniscal cysts may develop in the infrapatellar fat pad. In this article, the anatomical and imaging features of the infrapatellar fat pad will be summarized and the most common lesions will be illustrated.