MDCT Arthrography of the Hip: Value of the Adaptive Statistical Iterative Reconstruction Technique and Potential for Radiation Dose Reduction

Au cours des deux dernières décennies, la technique d'imagerie arthro-scanner a bénéficié de nombreux progrès technologiques et représente aujourd'hui une excellente alternative à l'imagerie par résonance magnétique (IRM) et / ou arthro-IRM dans l'évaluation des pathologies de la hanche. Cependant, elle reste limitée par l'exposition aux rayonnements ionisants importante. Les techniques de reconstruction itérative (IR) ont récemment été mis en oeuvre avec succès en imagerie ; la littérature montre que l'utilisation ces dernières contribue à réduire la dose d'environ 40 à 55%, comparativement aux protocoles courants utilisant la rétroprojection filtrée (FBP), en scanner de rachis. A notre connaissance, l'utilisation de techniques IR en arthro-scanner de hanche n'a pas été évaluée jusqu'à présent. Le but de notre étude était d'évaluer l'impact de la technique ASIR (GE Healthcare) sur la qualité de l'image objective et subjective en arthro-scanner de hanche, et d'évaluer son potentiel en terme de réduction de dose. Pour cela, trente sept patients examinés par arthro-scanner de hanche ont été randomisés en trois groupes : dose standard (CTDIvol = 38,4 mGy) et deux groupes de dose réduite (CTDIvol = 24,6 ou 15,4 mGy). Les images ont été reconstruites en rétroprojection filtrée (FBP) puis en appliquant différents pourcentages croissants d'ASIR (30, 50, 70 et 90%). Le bruit et le rapport contraste sur bruit (CNR) ont été mesurés. Deux radiologues spécialisés en imagerie musculo-squelettique ont évalué de manière indépendante la qualité de l'image au niveau de plusieurs structures anatomiques en utilisant une échelle de quatre grades. Ils ont également évalué les lésions labrales et du cartilage articulaire. Les résultats révèlent que le bruit augmente (p = 0,0009) et le CNR diminue (p = 0,001) de manière significative lorsque la dose diminue. A l'inverse, le bruit diminue (p = 0,0001) et le contraste sur bruit augmente (p < 0,003) de manière significative lorsque le pourcentage d'ASIR augmente ; on trouve également une augmentation significative des scores de la qualité de l'image pour le labrum, le cartilage, l'os sous-chondral, la qualité de l'image globale (au delà de ASIR 50%), ainsi que le bruit (p < 0,04), et une réduction significative pour l'os trabuculaire et les muscles (p < 0,03). Indépendamment du niveau de dose, il n'y a pas de différence significative pour la détection et la caractérisation des lésions labrales (n=24, p = 1) et des lésions cartilagineuses (n=40, p > 0,89) en fonction du pourcentage d'ASIR. Notre travail a permis de montrer que l'utilisation de plus de 50% d'ASIR permet de reduire de manière significative la dose d'irradiation reçue par le patient lors d'un arthro-scanner de hanche tout en maintenant une qualité d'image diagnostique comparable par rapport à un protocole de dose standard utilisant la rétroprojection filtrée.

Revue des arthroplasties totales de la hanche et du genou infectées--à propos de 28 cas [Review of infected total arthroplasties of the hip and knee--apropos of 28 cases]

This study is a long-term analysis of a group of patients with infected arthroplasties of the hip or the knee. We identified 28 patients with an infected arthroplasty (22 hips, 6 knees) documented by bacterial culture or on direct examination. At the time of diagnosis and on follow-up (a mean of 46 months after treatment) we evaluated the clinical picture, the radiological appearances of the articulation and the biological parameters. 19/28 patients showed a typical clinical picture, whereas in 9 others the picture was more doubtful. The treatments were 14 two-stage replacements of the arthroplasties, 7 simple resections, 5 conservative treatments and 2 one-stage replacements. On follow-up, 25 patients were considered as cured of their infection and 3 as failures. From a functional viewpoint, 9 patients showed no limitation, whereas 19 were limited in the daily activity. Half of the patients had no pain. Radiology showed that 20/26 evaluated patients had no signs of recurrence. Paraclinical examinations are important in the diagnosis of persistent low grade infections, particularly the demonstration of bacteria by pre-surgical sampling (fine needle aspiration, culture from draining sinuses). In spite of the cure of infection, the functional and painful sequellae are often considerable. As a result of our experience, we recommend a two-stage surgical procedure. Only when the general condition of the patient is poor, or when the infection is not under control, would we envisage an alternative procedure (arthrodesis, girdelstone, conservative).

Problème de surcharge de l'articulation coxo-fémorale chez l'adolescent [Overuse injuries of the hip in adolescents].

Painful femoro-acetabular impingement symptoms localized in the groin in flexion, adduction and internal rotation can be explained either by a primary disease of the labrum often post-traumatic, and more frequently as part of femoro-acetabular primary or secondary dysmorphia. The kinematic of the normal hip joint depends of peri-acetabular structures, geometry of joints and possible pathologies that could contribute to modify either the geometry or the proprioceptive function. By combining and analyzing these parameters it is possible to describe a joint concept of centricity, an essential parameter for optimal functions of the joint. The concept of overload is explained as the inability of the hip to ensure its centricity during activities that could lead to the occurrence of any degenerative disorders.

MDCT arthrography of the hip: value of the adaptive statistical iterative reconstruction technique and potential for radiation dose reduction.

OBJECTIVE: The purpose of this article is to assess the effect of the adaptive statistical iterative reconstruction (ASIR) technique on image quality in hip MDCT arthrography and to evaluate its potential for reducing radiation dose. SUBJECTS AND METHODS: Thirty-seven patients examined with hip MDCT arthrography were prospectively randomized into three different protocols: one with a regular dose (volume CT dose index [CTDIvol], 38.4 mGy) and two with a reduced dose (CTDIvol, 24.6 or 15.4 mGy). Images were reconstructed using filtered back projection (FBP) and four increasing percentages of ASIR (30%, 50%, 70%, and 90%). Image noise and contrast-to-noise ratio (CNR) were measured. Two musculoskeletal radiologists independently evaluated several anatomic structures and image quality parameters using a 4-point scale. They also jointly assessed acetabular labrum tears and articular cartilage lesions. RESULTS: With decreasing radiation dose level, image noise statistically significantly increased (p=0.0009) and CNR statistically significantly decreased (p=0.001). We also found a statistically significant reduction in noise (p=0.0001) and increase in CNR (p≤0.003) with increasing percentage of ASIR; in addition, we noted statistically significant increases in image quality scores for the labrum and cartilage, subchondral bone, overall diagnostic quality (up to 50% ASIR), and subjective noise (p≤0.04), and statistically significant reductions for the trabecular bone and muscles (p≤0.03). Regardless of the radiation dose level, there were no statistically significant differences in the detection and characterization of labral tears (n=24; p=1) and cartilage lesions (n=40; p≥0.89) depending on the ASIR percentage. CONCLUSION: The use of up to 50% ASIR in hip MDCT arthrography helps to reduce radiation dose by approximately 35-60%, while maintaining diagnostic image quality comparable to that of a regular-dose protocol using FBP.

Influence of the ankle arthropathies on the 3D kinematics of the lower limbs during gait: analysis with an ambulatory system.

Introduction: Ankle arthropathy is associated with a decreased motion of the ankle-hindfoot during ambulation. Ankle arthrodesis was shown to result in degeneration of the neighbour joints of the foot. Inversely, total ankle arthroplasty conceptually preserves the adjacent joints because of the residual mobility of the ankle but this has not been demonstrated yet in vivo. It has also been reported that degenerative ankle diseases, and even arthrodesis, do not result in alteration of the knee and hip joints. We present the preliminary results of a new approach of this problem based on ambulatory gait analysis. Patients and Methods: Motion analysis of the lower limbs was performed using a Physilog® (BioAGM, CH) system consisting of three-dimensional (3D) accelerometer and gyroscope, coupled to a magnetic system (Liberty©, Polhemus, USA). Both systems have been validated. Three groups of two patients were included into this pilot study and compared to healthy subjects (controls) during level walking: patients with ankle osteoarthritis (group 1), patients treated by ankle arthrodesis (group 2), patients treated by total ankle prosthesis (group 3). Results: Motion patterns of all analyzed joints over more than 20 gait cycles in each subject were highly repeatable. Motion amplitude of the ankle-hindfoot in control patients was similar to recently reported results. Ankle arthrodesis limited the motion of the ankle-hindfoot in the sagittal and horizontal planes. The prosthetic ankle allowed a more physiologic movement in the sagittal plane only. Ankle arthritis and its treatments did not influence the range of motion of the knee and hip joint during stance phase, excepted for a slight decrease of the hip flexion in groups 1 and 2. Conclusion: The reliability of the system was shown by the repeatability of the consecutive measurements. The results of this preliminary study were similar to those obtained through laboratory gait analysis. However, our system has the advantage to allow ambulatory analysis of 3D kinematics of the lower limbs outside of a gait laboratory and in real life conditions. To our knowledge this is a new concept in the analysis of ankle arthropathy and its treatments. Therefore, there is a potential to address specific questions like the difficult comparison of the benefits of ankle arthroplasty versus arthrodesis. The encouraging results of this pilot study offer the perspective to analyze the consequences of ankle arthropathy and its treatments on the biomechanics of the lower limbs ambulatory, in vivo and in daily life conditions.

Recessive multiple epiphyseal dysplasia (rMED) with homozygosity for C653S mutation in the DTDST gene - phenotype, molecular diagnosis and surgical treatment of habitual dislocation of multilayered patella: case report.

BACKGROUND: Multiple epiphyseal dysplasia (MED) is one of the more common generalised skeletal dysplasias. Due to its clinical heterogeneity diagnosis may be difficult. Mutations of at least six separate genes can cause MED. Joint deformities, joint pain and gait disorders are common symptoms. CASE PRESENTATION: We report on a 27-year-old male patient suffering from clinical symptoms of autosomal recessive MED with habitual dislocation of a multilayered patella on both sides, on the surgical treatment and on short-term clinical outcome. Clinical findings were: bilateral hip and knee pain, instability of femorotibial and patellofemoral joints with habitual patella dislocation on both sides, contractures of hip, elbow and second metacarpophalangeal joints. Main radiographic findings were: bilateral dislocated multilayered patella, dysplastic medial tibial plateaus, deformity of both femoral heads and osteoarthritis of the hip joints, and deformity of both radial heads. In the molecular genetic analysis, the DTDST mutation g.1984T > A (p.C653S) was found at the homozygote state. Carrier status was confirmed in the DNA of the patient's parents. The mutation could be considered to be the reason for the patient's disease. Surgical treatment of habitual patella dislocation with medialisation of the tibial tuberosity led to an excellent clinical outcome. CONCLUSIONS: The knowledge of different phenotypes of skeletal dysplasias helps to select genes for genetic analysis. Compared to other DTDST mutations, this is a rather mild phenotype. Molecular diagnosis is important for genetic counselling and for an accurate prognosis. Even in case of a multilayered patella in MED, habitual patella dislocation could be managed successfully by medialisation of the tibial tuberosity.

Tibio-talar arthrodesis with long anterograde nail after complex open fracture-dislocation of the ankle : P17

Introduction: Posttraumatic painful osteoarthritis of the ankle joint after fracture-dislocation often has to be treated with arthrodesis. In the presence of major soft tissue lesions and important bone loss the technique to achieve arthrodesis has to be well chosen in order to prevent hardware failure, infection of bulky implants or non-union. Methods: We present the case of a 53 year-old biker suffering of a fracture-dislocation of the ankle associated with a mayor degloving injury of the heel. After initial immobilization of the lesion by external fixation in Spain the patient was transferred to our hospital for further treatment. The degloving injury of the heel with MRSA infection was initially treated by repeated débridement, changing of the configuration of the Ex Fix and antibiotic therapy with favourable outcome. Because of the bony lesions reconstruction of the ankle-joint was juged not to be an option and arthrodesis was planned. Due to bad soft-tissue situation standard open fixtion with plate and/or screws was not wanted but an option for intramedullary nailing was taken. However the use of a standard retrograde arthrodesis nail comes with two problems: 1) Risk of infection of the heel-part of the calaneus/nail in an unstable soft tissue situation with protruding nail. And 2) talo-calcaneal arthrodesis of an initially healthy subtalar joint. Given the situation of an unstable plantar/heel flap it was decided to perform anklearthrodesis by means of an anterograde nail with static fixation in the talus and in the proximal tibia. Results:This operation was performed with minimal opening at the ankle-site in order to remove the remaining cartilage and improve direct bone to bone contact. Arthrodesis was achieved by means of an anterograde T2 Stryker tibial nail.One year after the anterograde nailing the patient walks without pain for up to 4 hours with a heel of good quality and arthrodesis is achieved. Conclusion: Tibiotalar arthrodesis in the presence of mayor soft tissue lesions and bone loss can be successfully achieved with antegrade nailing.

Failure of the surgical treatment in 115 infected hip arthroplasties-­analysis of a 12-­year prosthetic joint cohort study (1999-­2010)

Background:¦Infection after total or partial hip arthroplasty (HA) leads to significant long-­term morbidity and high healthcare cost. We evaluated reasons for treatment failure of different surgical modalities in a 12-­year prosthetic hip joint infection cohort study.¦Method:¦All patients hospitalized at our institution with infected HA were included either retrospectively (1999-­‐2007) or prospectively¦(2008-­‐2010). HA infection was defined as growth of the same microorganism in ≥2 tissues or synovialfluid culture, visible purulence, sinus tract or acute inflammation on tissue histopathology. Outcome analysis was performed at outpatient visits, followed by contacting patients, their relatives and/or treating physicians afterwards.¦Results:¦During the study period, 117 patients with infected HA were identified. We excluded 2 patients due to missing data. The average age was 69 years (range, 33-­‐102 years); 42% were female. HA was mainly performed for osteoarthritis (n=84), followed by trauma (n=22), necrosis (n=4), dysplasia(n=2), rheumatoid arthritis (n=1), osteosarcoma (n=1) and tuberculosis (n=1). 28 infections occurred early(≤3 months), 25 delayed (3-­‐24 months) and 63 late (≥24 months after surgery). Infected HA were¦treated with (i) two-­‐stage exchange in 59 patients (51%, cure rate: 93%), (ii) one-­‐stage exchange in 5 (4.3%, cure rate: 100%), (iii) debridement with change of mobile parts in 18 (17%, cure rate: 83%), (iv) debridement without change of mobile¦parts in 17 (14%, cure rate : 53% ), (v) Girdlestone in 13 (11%, cure rate: 100%), and (vi) two-­‐stage exchange followed by¦removal in 3 (2.6%). Patients were followed for an average of 3.9 years (range, 0.1 to 9 years), 7 patients died unrelated to the infected HA. 15 patients (13%) needed additional operations, 1 for mechanical reasons(dislocation of spacer) and 14 for persistent infection: 11 treated with debridement and retention (8 without change; and 3 with change of mobile parts) and 3 with two-­‐stage exchange. The average number of surgery was 2.2 (range, 1 to 5). The infection was finally eradicated in all patients, but the functional outcome remained unsatisfactory in 20% (persistent pain or impaired mobility due to spacer or Girdlestone situation).¦Conclusions:¦Non-­‐respect of current treatment concept leads to treatment failure with subsequent operations. Precise analysis of each treatment failure can be used for improving the treatment algorithm leading to better results.

Does previous hip arthroscopy negatively influence the short term clinical result of total hip replacement?

INTRODUCTION: The risk that hip preserving surgery may negatively influence the performance and outcome of subsequent total hip replacement (THR) remains a concern. The aim of this study was to identify any negative impact of previous hip arthroscopy on THR. METHODS: Out of 1271 consecutive patients who underwent primary THR between 2005 and 2009, 18 had previously undergone ipsilateral hip arthroscopy. This study group (STG) was compared with two control groups (CG, same approach, identical implants; MCG, paired group matched for age, BMI and Charnley categories). Operative time, blood loss, evidence of heterotopic bone and implant loosening at follow-up were compared between the STG and the MCG. Follow-up WOMAC were compared between the three groups. RESULTS: Blood loss was not found to be significantly different between the STG and MCG. The operative time was significantly less (p < 0.001) in the STG. There was no significant difference in follow-up WOMAC between the groups. No implant related complications were noted in follow-up radiographs. Two minor complications were documented for the STG and three for the MCG. CONCLUSION: We have found no evidence that previous hip arthroscopy negatively influences the performance or short-term clinical outcome of THR.

Cross-cultural adaptations of the Oxford-12 HIP score to the French speaking population.

BACKGROUND: An objective measurement of surgical procedures outcomes is inherent to professional practices quality control; this especially applies in orthopaedics to joint replacement outcomes. A self-administered questionnaire offers an attractive alternative to surgeon's judgement but is infrequently used in France for these purposes. The British questionnaire, the 12-item Oxford Hip Score (OHS) was selected for this study because of its ease of use. HYPOTHESIS: The objective of this study was to validate the French translation of the self-assessment 12-item Oxford Hip Score and compare its results with those of the reference functional scores: the Harris Hip Score (HHS) and the Postel-Merle d'Aubigné (PMA) score. MATERIALS AND METHODS: Based on a clinical series of 242 patients who were candidates for total hip arthroplasty, the French translation of this questionnaire was validated. Its coherence was also validated by comparing the preoperative data with the data obtained from the two other reference clinical scores. RESULTS: The translation was validated using the forward-backward translation procedure from French to English, with correction of all differences or mistranslations after systematized comparison with the original questionnaire in English. The mean overall OHS score was 43.8 points (range, 22-60 points) with similarly good distribution of the overall value of the three scores compared. The correlation was excellent between the OHS and the HHS, but an identical correlation between the OHS and the PMA was only obtained for the association of the pain and function parameters, after excluding the mobility criterion, relatively over-represented in the PMA score. DISCUSSION AND CONCLUSION: Subjective questionnaires that contribute a personal appreciation of the results of arthroplasty by the patient can easily be applied on a large scale. This study made a translated and validated version of an internationally recognized, reliable self-assessment score available to French orthopaedic surgeons. The results obtained encourage us to use this questionnaire as a complement to the classical evaluation scores and methods.

Infection prothétique de hanche à Listeria monocytogenes [Prosthetic hip infection due to Listeria monocytogenes: review of the literature and case report].

With the ageing of the population, articular prosthetic replacements are becoming more and more frequent. One of the most feared complications is prosthetic infection, mostly due to bacteria of the cutaneous flora. Listeria monocytogenes is rarely the cause. This paper describes the management of a hip prosthetic infection due to Listeria monocytogenes. The patient was cured with antimicrobial therapy and a two-stage exchange. This case report creates an opportunity to review the literature in the aim of determining the risk factors and the optimal care.

Five-Year Denosumab Treatment of Postmenopausal Women with Osteoporosis: Results from the first two Years of the Freedom Trial Extension

Objectives : The FREEDOM trial1 open-label extension is designed to evaluate the long-term efficacy and safety of denosumab for up to 10 years. We report the results from the first 2 years of the extension, representing up to 5 years of denosumab exposure.Materials/Methods : Postmenopausal women enrolled in the extension previously completed FREEDOM. During the extension, all women receive denosumab (60 mg) every 6 months and calcium and vitamin D daily. For the FREEDOM denosumab group, the data reflect 5 years of denosumab treatment (long-term group). For the FREEDOM placebo group, the data reflect 2 years of denosumab treatment (de novo group). P-values are descriptive.Results : There were 4550 (70.2%) FREEDOM women enrolled in the extension (2343 long-term; 2207 de novo). During the 4th and 5th years of denosumab treatment, the long-term group had further 1.9% and 1.7% increases in lumbar spine BMD and further 0.7% and 0.6% increases in total hip BMD (all P<0.0001 compared with extension baseline). Total BMD increases with 5-year denosumab treatment were 13.7% (lumbar spine) and 7.0% (total hip). In the de novo group, BMD increased during the first 2 years of denosumab treatment by 7.9% (lumbar spine) and 4.1% (total hip) (all P<0.0001 compared with extension baseline). After denosumab administration, serum CTX was rapidly and maximally reduced in both groups with the characteristic attenuation observed at the end of the dosing interval, as previously reported.2 Incidences of new vertebral and nonvertebral fractures were low and below rates observed in the FREEDOM placebo group. Adverse event reports were similar for both groups: in the long-term group, 83.4% reported AEs and 18.9% were serious. In the de novo group, the percentages were 82.8% and 19.4%, respectively. In FREEDOM, the respective percentages were 92.8% and 25.8% in the denosumab group and 93.1% and 25.1% in the placebo group. Two subjects in the de novo group had AEs adjudicated to ONJ which healed without further complications ; one resolved within the 6-month dosing interval and denosumab was continued. There were no atypical femoral fractures.Conclusions : Denosumab treatment for 5 years was well-tolerated and continued to significantly reduce CTX and significantly increase BMD. Reference: 1)Cummings;NEJM;2009;361:756, 2)Eastell;JBMR;2010; doi-10.1002/jbmr.251 Disclosure of Interest: This study was funded by Amgen; S Papapoulos: Consulting fees from Amgen, Merck, Novartis, Procter & Gamble, GSK, and Wyeth; R Chapurlat: Research grants and/or consulting fees from Amgen, Merck, Novartis, sanofi-aventis, Roche, Servier, and Warner Chilcott;ML Brandi: Research grants and/or consulting fees from Amgen, Eli Lily, GSK, MSD, NPS, Nycomed, Roche, Servier, and Stroder; JP Brown: Research grants and/or consulting or speaking fees from Abott, Amgen, Bristol Myers Squibb, Eli Lilly, Pfizer, Roche, Novartis, Merck, and Warner Chilcott; E Czerwinski: Research grants from Amgen, Astrazeneca, Danone Research, Eli Lilly, Merck Sharp & Dohme, Merck Serono, Novartis, Pfizer, Roche, SantoSolve AS, and Servier; N Daizadeh, A Grauer, C Libanati: Employed by Amgen and own Amgen stocks or stock options; M-A Krieg, D Mellstrom, H Resch: None; S Radominski: Research grants from Amgen, Pfizer, Novartis, Bristol-Myers Squibb, Roche, and Aventis; Z Man: Lecture fees and/or consulting fees from Merck, Novartis, Roche, and sanofi-aventis. Novartis steering committee member; JA Roman: Research grants from Roche; J-Y Reginster: Research grants, consulting fees, and/or lecture fees from Amgen, Analis, Bristol Myers Squibb, Ebewee Pharma, Genevrier, GSK, IBSA, Lilly, Merck Sharp & Dhome, Negma, Novartis, Novo-Nordisk, Nycomed, NPS, Roche, Rottapharm, Servier, Teijin, Teva, Theramex, UCB, Wyeth, and Zodiac; C Roux: Research grants and/or consulting fees from Amgen, MSD, Novartis, Servier, and Roche; SR Cummings: Research grants and/or consulting fees from Amgen, Eli Lilly, Novartis, and Merck; HG Bone: Research grants and/or consulting or speaking fees from Amgen, Eli Lilly, Merck, Nordic Bioscience, Novartis, Takeda, and Zelos