Introduction: The ilio-inguinal approach is used to achieve internal fixation of acetabular fractures. Although the outcomes of this procedure have been extensively reported, information is lacking on potential complications. More specifically, the effect on the ilio-psoas muscle, whose iliac attachments are almost completely released, has not been accurately evaluated.Hypothesis: Endopelvic dissection does not alter the ultrasound structure of the ilio-psoas muscle compared to the normal side at a distance from acetabular internal fixation via the ilio-inguinal approach.Patients and methods: We retrospectively evaluated 26 patients who underwent internal fixation of acetabular fractures via the ilio-inguinal approach between 2006 and 2010. Two patients with multiple injuries died shortly after the procedure, leaving 24 patients with unilateral fractures for the study. In 2012, an observer who was not involved in the surgical treatment of these patients conducted an assessment (Oxford score except in the 8 patients who required revision surgery for arthroplasty and evaluation for a deficit of the lateral femoral cutaneous nerve in the full cohort). At the same time point, ultrasonography was performed to compare ilio-psoas muscle morphology on the two sides. Any other complications (vascular, nervous, or parietal) were recorded.Results: Of the 24 patients, 11(45%) experienced complications, of whom only 3 required further surgery, 2 with infections that recovered fully after lavage and 1 with a haematoma responsible for compression of the urinary bladder. The lateral femoral cutaneous nerve was injured in 8 (33%) patients, including 4 who had achieved a full recovery at last follow-up. At last follow-up, none of the 24 patients had ultrasound evidence of a significant difference in ilio-psoas muscle size at the lateral window: mean transverse diameter was 51.8 + 0.8 mm (range, 44-58 mm) on the operated side versus 51.7 + 0.79 mm (range, 44-59 mm) on the other side (P= 0.9). After a mean follow-up of 49 months (range, 31-70 months), the mean Oxford score in the 16 patients who had not required further surgery was 20.5160 (range, 12-44).Discussion: Our results show that, despite extensive endopelvic dissection, the ilio-inguinal approach has no effect on the ultrasound morphology of the ilio-psoas muscle. There is a high risk of injury to the lateral femoral cutaneous nerve that should be disclosed to the patient before the procedure. In contrast, no parietal complications were recorded. In selected patients, the Cole-Stoppa approach is an alternative that spares the lateral femoral cutaneous nerve. Level of evidence: Level IV, retrospective study. (C) 2014 Elsevier Masson SAS. All rights reserved.

La voie d’abord ilio-inguinale est utilisée pour l’ostéosynthèse des fractures de l’acétabulum. Si les résultats des synthèses par cette voie sont connus, les complications ne sont pas décrites de façon détaillée et notamment le devenir du muscle psoas-iliaque, largement desinséré dans sa portion iliaque, n’est pas évalué avec précision. La dissection endopelvienne n’entrave pas la morphologie échographique du muscle psoas-iliaque par rapport au côté sain à distance d’une ostéosynthèse de l’acétabulum par voie ilio-inguinale. Nous avons évalué rétrospectivement 26 voies ilio-inguinales pratiquées entre 2006 et 2010 pour l’ostéosynthèse de l’acétabulum. Deux patients sont décédés précocement d’un polytraumatisme laissant 24 patients ayant une lésion unilatérale qui ont été évalués rétrospectivement en 2012 par un observateur non opérateur (score Oxford sauf pour les 8 patients repris par prothèse, recherche d’une atteinte déficitaire du nerf cutané latéral de la cuisse) et en échographie pour mesure comparative de la morphologie du muscle iliaque. Les autres complications ont été colligées (vasculaires, nerveuses, pariétales). Sur les 24 patients, nous dénombrons 11 (45 %) complications dont seulement 3 ont donné lieu à une nouvelle intervention : 2 infections ayant guéri après lavage, un hématome avec compression vésicale, et 8 atteintes du nerf cutané latéral de la cuisse (33 %) dont 4 ont récupéré au recul. Pour les 24 patients au recul, l’échographie n’a pas montré de différence significative sur la taille du muscle psoas-iliaque au niveau de la fenêtre latérale : diamètre transversal 51,8 mm ± 0,8 [44–58 mm] côté opéré versus 51,7 mm ± 0,79 [44–59 mm] (p = 0,9). Au recul moyen de 49 mois (31–70 mois), le score Oxford des 16 patients non repris était au recul de 20,5/60 (12 à 44). Cette série montre que malgré une dissection endopelvienne étendue, la voie ilio-inguinale ne retentit pas sur la morphologie échographique du muscle iliaque. Le taux d’atteinte du nerf cutané latéral de la cuisse est élevé et doit être annoncé au patient dans l’information préopératoire. En revanche, aucune complication pariétale n’a pas été observée. La voie de Cole-Stoppa constitue dans certaines indications une alternative qui permet d’épargner le nerf cutané latéral de la cuisse. Niveau IV. Étude rétrospective.

Purpose of the study: For young active patients, implantation of metal backed socket with a metal-on-metal bearing is an attractive tribological alternative when a standard prosthesis cannot be implanted. Metal ion assays have not been reported in this type of population. The purpose of this work was to present the clinical, radiographic and metal ion results. Material and methods: Between 1998 and 2003 23 total hip arthroplasties (THA) (six primary and 17 revision) were implanted with a cemented Metasul™ bearing in a Muller inlay. Mean follow-up was 6.1 years (5–10). None of the patients was lost to follow-up. The Harris and PMA scores were noted as were signs of implant loosening or migration. Metal ions were assayed in total blood (Cr and Co) by mass spectrometry and atomic emission spectrometry (Ti). Results: At follow-up, the mean Harris and PMA scores were significantly increased, from 62.2 to 95.2 (p = 0.01) and from 12.9 to 17.4 (p = 0.02) respectively. No revisions were required for aseptic loosening or failure of fixation. The radiographs did not reveal any signs of osteolysis or lucency. The mean levels of Cr, Co and Ti were 1.85μg/l (0.8–3.2). 1.24μg/l (0.5–1.86) and 9.62μg/l (5–18) respectively. Ti > 10μg/l was noted in six patients; Ti > 10 μg/l and Cr > 2μg/l in five patients. There was no correlation of metal ion levels with size of the implants, activity level, gender, clinical scores or cup inclination. Discussion: The mean Co and Cr levels observed in this series were similar to those reported in the literature for standard THA (cementless press fit cups). Ti levels have only been reported in rare studies so that comparison with other series is hazardous. The Ti level observed here appeared to depend on the femoral stem resurfacing (in our series, the porous surface of the stem was coated with a Ti-6Al-7nB alloy). Conclusion: Cementing the metal-on-metal bearing in the supporting inlay appears to be a reliable and attractive technique for this young and active population. Levels of Cr and Co in blood were the same as reported for standard implants. These levels of metal ions should be followed to confirm the long-term results.

Les fractures interprothétiques sont une entité rare et grave, source de difficultés de consolidation et de stabilisation en raison de conditions mécaniques défavorables liées à la fragilité osseuse et à l’encombrement prothétique. Le but de ce travail était de souligner les difficultés de prise en charge de ces fractures, les options thérapeutiques et les constatations réalisées amenant à proposer un complément aux classifications de Vancouver pour la hanche et de la Société française de chirurgie orthopédique et traumatologique (Sofcot) pour le genou. Il s’agit d’une série rétrospective multicentrique de 14 fractures fémorales interprothétiques dont huit cas de type double C (type C pour la hanche et le genou) de cinq cas de type C autour de la hanche et type B autour du genou et un cas de type double B (type B pour la hanche et le genou). Ces fractures étaient survenues sur un implant standard (n = 15) ou de révision (n = 13). Ainsi, dans six cas la fracture concernait un fémur envahi par une quille d’extension fémorale de prothèse totale de genou (PTG) et dans huit cas, il s’agissait de PTG sans quille diaphysaire fémorale, assimilables à des fractures type C. Aucune des six fractures sur PTG contrainte à quille n’a consolidé de première intention alors que sept des huit fractures de type C ont consolidé de première intention. À terme, 12 cas ont évolué favorablement au prix de trois reprises par fémur complet, un patient décédait à six mois non consolidé et non repris, et un patient restait en attente d’un fémur prothétique complet. Pour décrire l’état du fémur intermédiaire et son envahissement médullaire, nous proposons l’ajout d’une classe D aux classifications Sofcot et Vancouver, correspondant aux fractures interprothétiques survenant autour d’une PTG avec quille d’extension diaphysaire. L’ostéosynthèse d’une fracture interprothétique doit faire appel à une fixation longue pontant les deux prothèses. En cas d’implant descellé, un changement peut être proposé, mais en cas d’extension diaphysaire, le fémur résiduel entre les extensions diaphysaires doit être protégé des pics de contraintes par une plaque étendue en amont et en aval. Face à un stock osseux limité, par ostéolyse ou en raison d’un envahissement médullaire fémoral initial, qui plus est si un ou deux des implants sont descellés, l’indication d’un fémur prothétique complet peut être discutée car les possibilités de consolidation apparaissent limitées en raison d’une situation mécanique précaire. Type IV rétrospectif.

Nous rapportons le cas d’une patiente de 34 ans qui a présenté à six semaines de la fixation d’une fracture de l’acétabulum par voie iliofémorale élargie une subluxation antérolatérale de la tête fémorale. En l’absence d’incongruence articulaire recherchée sur les radiographies et la tomodensitométrie, une capsulorraphie a été menée par voie antérieure de Hueter. Cette plastie capsulaire a permis de stabiliser la hanche pendant deux ans, mais une dégradation arthrosique a conduit à effectuer une arthroplastie. Au recul de deux ans, l’évolution de l’arthroplastie secondaire était favorable. L’importante exposition musculaire de la face latérale de l’acétabulum et la capsulotomie circonférentielle liées à l’usage de la voie iliofémorale ont été retenues comme facteurs favorisants de cette complication. En cas d’impossibilité de mobilisation précoce postopératoire, un maintien temporaire du membre en abduction et flexion peut être recommandé après la réalisation d’une voie iliofémorale élargie avec capsulotomie circonférentielle.

Purpose of the study: Drilling along yields disappointing results for osteonecrosis of the femoral head due to the high failure rate despite prolonged rest and also because of the risk of fracture. To prevent these problems, we have developed a new drilling technique which was evaluated prospectively. Material and methods: The procedure performed percutaneously uses a lateral cortical orifice measuring 5mm, non-concentrated autologous bone marrow was injected after drilling. Osteoinductive protein (BMP7) was associated in random fashion (groups BMP+ and BMP−). Ficat stage 1 and 2 necrosis was included. Outcome was the rate or revision for prosthesis. Results: Forty hips (36 patients) were included and assessed at mean four years (range 2–6). The necrosis was related to: alcoholism (n=5), cortisone (n=25), barotraumas (n=2), metabolic disease (n=4), idiopathic condition (n=4). Group BMP- (drilling+bone marrow) included 24 hips and group BMP+ (drilling+bone marrow+BMP7) 16 hips. The groups were comparable regarding necrosis stage (15% stage 3, 65% stage 2, 20% stage 1) and mean Koo index (27 BMP+ vs 34 BMP-; NS). There were no infections and no fractures despite immediate and complete weight-bearing. The revision rate for prosthesis was higher in the BMP- group (67%) than in the BMP+ group (43%) but the difference did not reach significance (p=0.10). The failure rate was not affected by the severity of the necrosis in the BMP+ group: all stage 3 hips were revised in the BMP- group versus none in the BMP+ group. The only variable predictive of revision for prosthesis was the Koo index (p=0.02). Discussion: Adjunction of BMP did not improve significantly the success rate of drilling with bone marrow adjunction but adding BMP appeared to limit the unfavourable impact of server necrosis observed in the BMP- group. To reach a statistical power of 80%, 40 cases would be needed in each arm. This threshold has not yet been reached. It can be noted however that the proposed method does ensures early weight bearing without the risk of complications. Similarly, since it is a percutaneous procedure, later arthroplasty is not compromised. The principle confounding factor, the richness of the bone marrow, was not assessed, motivating a new randomized trial with measurement of CFU-F.

We report the case of a 34-year-old female patient who, six week following her acetabular fracture ORIF through an extended iliofemoral approach, presented with anterolateral incomplete dislocation of the femoral head. In the absence of joint incongruence as demonstrated on radiographs and CT images, a capsular tightening was performed via the anterior Hueter approach. This capsular plasty stabilized the hip for 2 years, but gradual osteoarthritis deterioration resulted in the need for arthroplasty. At the 2-year follow-up, this secondary arthroplasty showed satisfactory result. The substantial muscle exposure of the lateral aspect of the acetabulum and the circumferential capsulotomy related to the use of the iliofemoral approach were retained as factors promoting this complication. In case early postoperative mobilization is impossible, temporarily maintaining the limb in abduction and flexion can be recommended after an extended iliofemoral approach with circumferential capsulotomy.

Introduction: Interprosthetic fracture is a rare but serious entity, impairing consolidation and stability due to adverse mechanical conditions related to bone fragility and implant volume.Objective: The present study highlights the difficulties involved in managing such fractures, details treatment options and reports findings leading to a proposed additional grade in the comparable Vancouver (hip) and French Orthopedic and Traumatologic Surgery Society (Societe francaise de chirurgie orthopedique et traumatologique: SoFCOT) (knee) classification systems. Patients and methods: A multicenter retrospective series included 14 interprosthetic femoral fractures: eight type double C (type C for both hip and knee), five type C for hip and B for knee, and one type double B (type B for both hip and knee) on the Vancouver and SoFCOT classifications. Fracture occurred on standard (n = 15) or revision (n = 13) implants. Six cases involved a femoral shaft encumbered by a total knee replacement (TKR) femoral extension stem and eight cases TKR without femoral long stem, assimilable to type C fracture.Results: None of the six fractures proximal to a constrained TKR with stem-achieved union by primary intention, whereas seven of the eight type-C fractures did so. Finally, 12 cases showed favorable evolution, with three secondary total femur replacements (TFR) and one death at 6 months without bony union or revision and one patient waiting for TFR.Discussion: To describe the status of the intermediate femur and its medullary canal encumbrance, we propose adding a category D to the SoFCOT and Vancouver classifications, corresponding to interprosthetic fracture on TKR with diaphyseal extension stem. Interprosthetic fracture internal fixation should begin with long devices bridging the two prostheses. When the implant is loose, it may be replaced; in case of diaphyseal extension, however, the residual femur between the two extensions should be protected against peak stress by a plate extending upward and downward. In case of limited bone stock, due to osteolysis or initial femoral medullary canal compromise, especially if one or both implants are loose, TFR may be indicated as consolidation, is jeopardized by the uncertain mechanical situation.Level of evidence: Level IV, retrospective study. (C) 2011 Elsevier Masson SAS. All rights reserved.

Purpose of the study: Locked implants have yielded favourable results for femoral bone reconstruction for revision total hip arthroplasty, but defective integration has also been reported due to insufficient bioactive coating. The purpose of this work was to evaluate a locked pivot with a two-third proximal hydroxyapatite coating. Material and methods: From 1996 to 2007, 158 femoral implants (Linea™) were implanted for hip arthroplasty revision. The 143 cases with more than one year follow-up were reviewed (14 deaths, 1 lost to follow-up); 83 revisions for aseptic loosening, 41 periprosthetic fractures, 19 revisions in an infected context. Patients were reviewed retrospectively by a non-operator observer. These were older patients (mean age 68 years, range 31–93) and 36 patients had complex situations requiring at least two prior prostheses; 25% had severe grade 3 or 4 (SOFCOT) bone lesions and 59% diaphyseal damage. Results: Clinical improvement was significant, the Postel Merle d’Aubigne score improved from 7.7 + 4.3 (0–17) to 15.6 + 2.2 (8–18) at mean 50 months (14–131) (p Discussion: Compared with older models of locked pivots, this implant reduced the rate of thigh pain while allowing constantly satisfactory bone reconstruction. The metaphyseal and diaphyseal filling index is the main factor predictive of clinical and radiological success by favouring osteointegration. Maximal filling, obtained with a full range of implant diameters and lengths, contributes to this good result.

Introduction: Cementless revision hip arthroplasties require a stable initial fixation that does not compromise a subsequent bone reconstruction. In case of severe femoral bone loss, stems usually requires distal fixation that may induce stress shielding and finally reduce the spontaneous bone reconstruction. We introduced the use of distally locked revision stems in 1993 hoping strong fixation and bone reconstruction. The goal of the current study was to assess if these components fulfill these two objectives.Materials and Methods: 101 cementless femoral revision stems with distal locking by screws (Ultime™ Wright-Cremascoli) were inserted from 1993 to 2001. These stems were smooth distally and porous coated with or without HA 1/3 proximally. The indication to use these components was severe bone loss (Paprosky grade IIC and III in 51%) when press fit distal fixation could not be obtained. The use of bone graft was limited to segmental defects or to treat trochanteric non-union. An extended trochanteric osteotomy was performed in 89%. The revision was performed because of aseptic loosening in 43,4%, periprosthetic fracture in 24,2% and infected loosening in 25,2%. The results were assessed after a mean follow-up of 6 years (5–12).Results: 13 patients deceased and 2 were lost for follow-up. All the extended trochanteric osteotomies healed. Merle d’Aubigne hip score increased from 8.3 to 13.4, but thigh pain was observed in 44%. Bone reconstruction was significant according to Hoffman index at 3 levels of assessment. The 5-year survivorship was 87% considering aseptic revision for any reason. Seventeen repeated femoral procedures were performed: 9 related to thigh pain (because there was no proximal osteointegration) that were revised for short primary stems, 8 because of stem fractures (all occurred at the level of the proximal hole with the same stem size because there was no proximal fixation as long as the stems were smooth or without HA-coating.Discussion: This serie has the longest follow-up using locked revision stems. Despite severe pre-operative bone loss, primary fixation and significant bone reconstruction were obtained for all the cases without extensive bone grafting. The major weakness, thigh pain and stem break, were related to unadequate femoral coating for these cementless stems that did not achieved osteointegration. Conversly, the reoperations were simple, allowing the use of short primary designs as bone reconstruction was achieved in all cases without extensive bone grafting. These locked stems allow a strong primary distal fixation that does not compromise bone regeneration. An improvement of femoral coating (extension to 2/3 and use of hydroxyapatite) may reduce the rate of thigh pain and reoperation.

Diagnosis of total hip arthroplasty malfunction is usually based on clinical and radiographic findings, while metal ion blood levels monitoring is generally recommended for metal-on-metal bearings hip replacements. However, these measurements may be very useful in detecting anomalies in other bearing surfaces such as plasma sprayed ceramic bearings. We report on the case of a patient with a painful cementless ceramic-on-ceramic total hip prosthesis (Plasmaceram) for which metal ions blood levels suggested revision surgery in the absence of any demonstrable radiographic anomaly. The high Cobalt and moderate Chromium ion levels in blood suggested a mechanical dysfunction of the bearing couple which revealed to be a severe cam effect requiring revision surgery of both components. Measurement of metal ion blood levels may play a substantial role in the assessment of a total hip prosthesis mechanism when using another bearing surface than metal-on-metal for which this measurement is usually recommended.

Le défaut de fonctionnement d’une arthroplastie totale de hanche est habituellement diagnostiqué sur des arguments cliniques et radiographiques, tandis que les dosages d’ions métalliques sanguins ne sont recommandés que pour la surveillance des prothèses à frottement métal-métal. Ces dosages peuvent s’avérer très utiles afin de détecter l’anomalie de fonctionnement d’autres couples de frottement comme le métal céramisé. Nous rapportons le cas d’une patiente porteuse d’une arthroplastie totale de hanche sans ciment douloureuse porteuse d’un couple de frottement dur-dur en métal céramisé (Plasmaceram™), pour lequel les résultats des dosages sanguins ont été décisifs à l’indication de révision en l’absence d’anomalie radiographique. L’élévation importante du Cobalt et modérée du Chrome dans le sang total faisait suspecter une anomalie du couple de frottement qui s’est révélée être un effet came sévère et a conduit à la révision des deux composants. Le dosage des ions métalliques sanguins peut être utile à l’évaluation du fonctionnement d’une prothèse totale de hanche avec un couple de frottement d’un autre type que le métal-métal pour lequel il est classiquement recommandé.

Purpose of the study: Theoretically, long-term functional and radiographic degradation is predictable after ankle fusion, but sound evidence from consecutive analysis of the same cohort is lacking. The purpose of this study was to evaluate the same cohort of patients who underwent ankle fusion. Material and Methods: The cohort included 52 ankle fusions which had been analyzed in 1984 at seven years (2–22 years) of follow-up then again in 2000 using the same evaluation criteria. Among the 52 patients, six were lost to follow-up, 20 had died and one had undergone leg amputation. The second analysis thus included 25 patients (18 men and 7 women), mean age 62±12.6 years (40–94) at the 2000 assessment performed 23±4.5 years (19–36 years) after the fusion. Functional outcome was assessed with the 100-point Duquennoy scale. Osteoarthritis of the subtalar and mediotarsal joints were assessed preoperatively and at follow-up using the same scale. Results: The functional outcome did not deteriorate significantly between 1984 and 2000. The mean score was 65.8±22.6 (19–92) in 1984 and 64.7±18.3 (34–90) in 2000 (p=0.67). Fifteen patients (60%) had a good or very good outcome at seven years, and 14 (56%) at 23 years. Between 1984 and 2000, ten patients improved their score (on average 10.4 points, range 1–21 points), two had an unchanged score and thirteen a lower score (on average 10 points, range −1 to −24). Ten of these thirteen patients developed severe intercurrent conditions explaining the degradation. At last follow-up, sixteen ankles were pain free or nearly pain free. Twelve patients considered their ankle as a forgotten problem and had no regrets concerning the operation. The evolution of the subtalar joint in 16 cases (nine fusions including five at the same time as the ankle fusion and four performed within four years) showed that all developed early osteoarthrtic degradation with aggravation between 1984 and 2000, leading in the majority of cases to severe degenerative disease. This osteoarthritis was painful in less than one-third of the cases (including the four secondary subtalar fusions and the four sub-talar fusions which were painful at mobilization). The mediotarsal joints degradation was later and less severe than for the subtalar joint with a majority of moderate osteoarthritis. Ten ankles exhibited compensatory hypermobility of the forefoot measured at more than 15° without pain. Discussion: This long-term follow-up with two successive assessments using the same evaluation criteria did not demonstrated late degradation of function expected after ankle fusion. It did show however the presence of radiographic degradation of the subtalar joint but with little clinical expression at a minimal follow-up of 19 years. There was no need for complementary fusion between 4 and 23 years follow-up.

Les couples de frottement dur-dur peuvent imposer une modularité acétabulaire, pour laquelle le polyéthylène est fréquemment utilisé comme pièce d’interposition (sandwich). Cependant, les différences de module d’élasticité rendent incertaine la fixation de l’insert. Le but de ce travail était de rapporter un cas bilatéral de dessertissage entre l’insert métallique et le sandwich de polyéthylène d’un couple métal-métal. Une arthroplastie bilatérale en deux séances à quatre mois d’intervalle était pratiquée chez une femme de 53ans pour une nécrose après corticothérapie. Les prothèses comportaient un pivot sans ciment, une cupule hémisphérique impactée dans laquelle était placé un sandwich de polyéthylène avec un insert métallique (Sikomet™). Trois ans plus tard, elle consultait en raison d’un bruit anormal sur la hanche droite et la radiographie était jugée normale. Trois mois plus tard, elle consultait de nouveau devant la persistance du bruit. Une dissociation entre l’insert métallique et le sandwich de polyéthylène était alors diagnostiquée, motivant un changement acétabulaire au profit d’un couple métal-polyéthylène. Après des suites simples, la patiente décrivait quatre mois plus tard la même complication à gauche, motivant la même révision. Au cours des reprises, une ostéolyse secondaire à une métallose était constatée, justifiant dans les deux cas une synovectomie et une allogreffe acétabulaire de comblement. Les suites opératoires ont été émaillées à gauche de trois luxations sur neuf mois, traitées orthopédiquement sans récidive. Il s’agit du premier cas bilatéral de dessertissage quasiment simultané décrit entre un insert dur-dur et un sandwich de polyéthylène. Ce cas bilatéral implique un défaut de fixation de l’insert dans le polyéthylène. Cette observation rappelle que tout bruit anormal sur un couple de frottement dur-dur doit faire rechercher une complication mécanique (dessertissage, fracture d’implant…) et confirme la nécessité de surveillance des arthroplasties et l’importance de la sémiologie radiographique. La faible teneur en carbone du couple Sikomet™ peut être incriminée dans cet échec par l’augmentation du couple de friction, et par la métallose déjà observée dans la littérature avec ce modèle d’implant.

Introduction: Hard-on-hard bearings for total hip replacement may require a modular acetabular inlay for which polyethylene is often used in a sandwich-type configuration. However, differences in the elastic modulus of the materials make fixation of this metal insert uncertain. The aim of this study is to report a case of bilateral separation of the metal insert from the polyethylene sandwich in a metal-on-metal bearings prosthesis.Materials and methods: A bilateral total hip arthroplasty was performed in two operations, four months apart, in a 53-year-old woman following a corticosteroid-induced osteonecrosis. The total hip replacement system included a cementless stem, and a press-fit hemispheric cup containing a polyethylene sandwich with a metallic insert (Sikomet (TM)).Results: Three years later, the patient consulted because of abnormal noise in her right hip which appeared normal on conventional X-ray. Three months later she consulted again for persistent noise. Separation of the metal insert from the polyethylene sandwich was diagnosed and an acetabular revision was performed selecting a metal-on-polyethylene articulation system. The postoperative course, for this revision, was uneventful, but the patient returned with the similar symptoms in her left hip four months later, resulting in the same type of revision. During the revisions, osteolysis secondary to metallosis was diagnosed, requiring synovectomy and acetabular reconstruction with morcelized allograft impaction. The left side postoperative course included three dislocations in nine months which were conservatively treated and have not since recurred.Discussion and conclusion: This is the first reported case recording an almost simultaneous bilateral dissociation of a hard-on-hard inlay from its polyethylene sandwich. This bilateral case suggests that the fixation of the metal insert inside the polyethylene was probably defective. This case is also a reminder that mechanical complications (separation, implant fracture) should be searched for in presence of any abnormal noise occurring after hard-on-hard bearings prosthetic implantation. This confirms the necessity of periodical follow-up of hip arthroplasties and the importance of knowing their radiological features. The low carbon content of the Sikomet (TM) bearing may have been the cause of this failure by increasing frictional torque on the bearing surface, causing metallosis which has already been described in the literature in this type of hip replacement system. (c) 2009 Elsevier Masson SAS. All rights reserved.

Purpose of the study: Because of its specific properties, linezolid (LZD) is an alternative to glycopeptides for the treatment of BJI causes by resistant Gram-positive cocci. The efficacy and tolerance of long-term (> 28d) administration remain to be determined with precision. Material and methods: This was a retrospective analysis of the files of patients who received long-term LZD for BJI with a post-treatment follow-up of at least twelve months. Results: Between January 2001 and December 2003, 68 patients (mean age 54.6 years) received LZD (600 mg/12h) intravenously then orally for a mean duration of 14.6 weeks on average (range 6–36 weeks). The orthopedic implants were infected in 31 patients (45.6%, 27 prostheses and 4 external fixators). A fistulization was diagnosed in 29 patients (42.6%). Medical and surgical treatment was undertaken in 51 patients (75%). Germs isolated from deep samples were staphylococci (n=57, 51 meti-R), and strepotococci (n=11). A polymicrobial infection was recorded in six patients (8.8%). Clinical success was achieved in 52 patients (76.5%) at the end of treatment, a result which was sustained for 48 of them to mean follow-up of 16.8 months (range 12–48). Sixty-three episodes of side effects were noted: anemia (n=29), peripheral neuropathy (n=9), nausea (n=14), headache (n=2), neutropenia (n=2), and thrombopenia (n=1), leading to discontinuation of LZD in 23 patients (33.8%) on average 11.9 weeks (range 6–36) after onset of treatment. Fifteen patients (22.1%) required transfusion. Discussion: Among the patients in this series with BJI, most caused by a multiresistant germ, the rate of success was satisfactory (48/68, 70.6%) with LZD. Treatment was associated with a high frequency of serious adverse effects leading to discontinuation in one-third of patients. Conclusion: Long-term treatment of BJI with LZD appears to be effective, including in patients with infected orthopedic material. Conversely, tolerance problems can limit is use to infections caused by mul-tiresistant Gram-positive cocci unresponsive to other compounds.