Dual-mobility tripod cup for revision hip arthroplasty: long-term (five to fourteen years) evaluation of a new generation cementless implant.

PURPOSE: The aims of this study were to evaluate the survivorships of a new generation cementless DMC with tripod additional fixation in revision total hip arthroplasty and complications at a minimum five year follow-up. METHODS: One hundred and fifteen revisions (THA) treated with tripod DMC performed between 2009 and 2015 were included in this retrospective study. Acetabular defects were classified as Paprosky 1 (n = 38, 33%), 2 (n = 75, 65%) or 3 (n = 2, 2%). Unipolar or bipolar revision was performed for the following indications: aseptic acetabular loosening (63%), infection (14%), aseptic bipolar loosening (11%), instability (4%), aseptic femoral loosening (3%), ALVAL (3%) and iliopsoas impingement (2%). Mean follow-up was 9.4 years ± two (range, 5 to 14). RESULTS: At the final follow-up, a single episode of dislocation occurred within three months after the procedure (0.8%) with no revision. Three cases of aseptic loosening were diagnosed (2.6%). Four infections (3.5%) required reoperation: three required a two stage bipolar revision; one was treated by DAIR procedure. At the latest follow-up, the survivorship of the acetabular cup for aseptic loosening was 98% [95% CI (91.2-99.4)] and for any reasons was 94.4% [95% CI (90.1%-98.9%)]; the mean HHS improved from 60 points (range, 18-94 points) to 83 points (range, 37-100 points) (p < .001). CONCLUSION: This study reports a low complication rate in favour of the use of a tripod DMC in revision THA with a satisfactory survivorship at a ten year follow-up.

Evaluation of the arterial kink point during flexion of the hip: A dynamic angiographic study in iliac endofibrosis patients.

PURPOSE: The aim of the study was to determine the flexion point's location of the ilio-femoral arterial axis and its angulation. MATERIALS AND METHODS: Thirty-seven dynamic digital subtraction angiographies were analyzed and were included in the current study. Different lengths were measured, based on specific anatomical landmarks: the origin of the external iliac artery, the inguinal ligament and the bifurcation of the femoral artery. These lengths were measured in extension and during flexion of the hip in order to determine the flexion point of the artery. RESULTS: In extension, some physiological angulations of the external iliac artery were measured. During flexion of the hip joint, the distance from the kink point to the bifurcation of the common iliac artery was respectively 82 ± 21 mm (range 48-116) on the right side and 95 ± 20 mm (range 59-132) on the left side. The distance from the kink point to the inguinal ligament was respectively 38 ± 40 mm (range 12-138) on the right side and 26 ± 23 mm (range 8-136) on the left side. The distance from the kink point to the bifurcation of the femoral artery was respectively 45 ± 29 mm (range 15-107) on the right side and 27 ± 12 mm (range 10-66) on the left side. During flexion, the angulation of the flexion point of the ilio-femoral axis was 114 ± 18° (range 81-136°). CONCLUSIONS: The flexion point was located cranially to the inguinal ligament and below the departure of the external iliac artery.

An anatomical study of the meniscal roots of the knee: landmarks for its surgical reconstruction and implications for knee surgeons.

PURPOSE: The aim of this anatomical study was to describe the anatomy of the meniscal roots and their relationships with respect to the main adjacent structures in order to improve their surgical reconstruction. METHODS: Fourteen knees were included. The mean age of the donors was 92 years (range 89-96). We studied the general characteristics of the anterior and posterior roots of the medial meniscus and lateral meniscus by measuring their widths at their base and area. We investigated the relations between anterior and posterior roots of the medial and lateral menisci with respect to the anterior and posterior cruciate ligaments (ACL and PCL). RESULTS: The mean width of the anterior root of the lateral meniscus was 10.5 ± 1.4 mm. The mean width of the anterior root of the medial meniscus was 10 ± 1.5 mm. The mean width of the posterior root of lateral meniscus was 11.4 ± 1.4 mm. The mean width of the posterior root of medial meniscus was 10.5 ± 1.0 mm. The mean distance between the anterior cruciate ligament and the anterior root of lateral meniscus was 9.8 ± 2.9 mm, for the medial meniscus it was 15.9 ± 3.4 mm. The mean distance between the posterior cruciate ligament and the posterior root of the lateral meniscus was 11.5 ± 2.7 mm, for the medial meniscus, it was 11 ± 2.6 mm. CONCLUSION: The anterior and posterior meniscal roots have precise landmarks, and this article contributes to define the location of the meniscal roots with respect to their adjacent anatomical structures: ACL, PCL and intercondylar tubercle. Having precise measures of the distances between the meniscus roots and these structures allows knee surgeons to perform ACL reconstruction, meniscal root repair and meniscal allograft transplantation.

Relationships of the superficial fibular nerve and sural nerve with respect to the lateral malleolus: implications for ankle surgeons.

PURPOSE: Superficial fibular nerve (SFN) and sural nerve are at risk during osteosynthesis of the lateral malleolus. The aim of this anatomical study was to describe the relationships of the superficial fibular and sural nerves with respect to the lateral malleolus. METHODS: Nine corpses (18 ankles) were dissected, using a direct lateral approach. Measurements were recorded between the fibula and the nerves, and the pattern variations of the SFN were recorded for both right and left side to assess intra-individual variability. RESULTS: Distance between the tip of the lateral malleolus and the piercing of fascia cruris was 111 ± 26 mm for type 1 pattern, and range was 46-161 mm all types included. 78% (14 SFN) were type 1 pattern, 17% (3 SFN) were type 2 pattern, and 5% (1 SFN) were type 3 pattern. 44% (4 specimen) had a type 1 pattern SFN on one ankle and another pattern on the other ankle. The sural nerve was always observed just posterior to the lateral malleolus. CONCLUSION: This study demonstrated a great inter-individual variability especially for the SFN, but also an intra-individual variability with frequent different patterns between right and left leg. It is important to know the anatomical variations of the SFN and sural nerve to decrease the risk of intra operative nerve injury during direct lateral approach of lateral malleolus.

Tarsal Tunnel Syndrome: Outcome According to Etiology.

Surgical results in tarsal tunnel syndrome are variable, and etiology seems to be a factor. Three possible etiologies can be distinguished. The aim of the present study was to compare surgical results according to etiology. Three continuous retrospective series (45 patients overall) of tarsal tunnel syndrome were compared. Group 1 presented a permanent intra- or extra-tunnel space-occupying compressive structure. Group 2 presented intermittent intra-tunnel venous dilatations. Group 3 comprised idiopathic tarsal tunnel syndrome. The mean follow-up was 3.6 +/- 1.8 years. The main endpoint was subjective postoperative improvement on Likert scale. Group 1 reported greater improvement than groups 2 and 3. Preoperative neuropathy on ultrasound was associated with poorer improvement, which was not the case for neuropathy on electromyography. Surgical treatment of tarsal tunnel syndrome provides better results in etiologies involving structural compression.

Safety and efficacy of a strategy of vitamin K antagonist reversal with prothrombin complex concentrates compared to vitamin K in patients with hip fracture.

Background: Increased preoperative delay in patients with hip fractures may be responsible for increased morbidity and mortality. We hypothesized that a strategy of reversal of vitamin K antagonist (VKA) by prothrombin complexes concentrates (PCCs), as compared to vitamin K, is safe and reduces preoperative delay and hospital length of stay (LOS). Methods: In this pilot study, we reviewed the records of patients admitted to a university-affiliated hospital for hip fracture between Jan. 1, 2012, and Dec. 31, 2016, who were taking VKA. Patients were stratified according to reversal strategy (vitamin K v. PCC). Adverse effects, time to surgery, LOS and mortality were collected from the electronic medical record and were compared between the 2 study groups and a control group not treated with VKA. Results: A total of 141 patients were included in the study: 65 in the vitamin K group, 26 in the PCC group and 50 in the control group. The median preoperative delay in the PCC group (20 h [interquartile range (IQR)] 13-25 h]) and the control group (20 h [IQR 15-33 h]) was lower than that in the vitamin K group (45 h [IQR 31-52 h]) (p < 0.001). Patients in the PCC group had a shorter median hospital LOS than those in the vitamin K group (6 d [IQR 4-9 d] v. 8 d [IQR 6-11 d], p < 0.05). No difference was observed in the proportion of patients who received a red blood cell transfusion, or had thrombotic or hemorrhagic complications. No difference in mortality at 12 months was observed between the groups. Conclusion: In patients with hip fracture, the use of PCCs as compared to vitamin K to reverse the effect of VKA significantly reduced preoperative delay and hospital LOS, and was not associated with an increase in the rates of thrombotic or hemorrhagic complications. Prospective studies involving a greater number of patients are required to confirm these promising results.

Contexte: L'allongement du délai préopératoire chez les patients atteints d'une fracture de la hanche pourrait expliquer l'augmentation de la morbidité et de la mortalité. Selon notre hypothèse, une stratégie d'inversion des antagonistes de la vitamine K (AVK) au moyen de concentrés de complexes prothrombiques (CCP), plutôt que de vitamine K, est sécuritaire et réduit le délai préopératoire et la durée du séjour hospitalier. Méthodes: Pendant cette étude pilote, nous avons passé en revue les dossiers de patients sous AVK admis dans un centre universitaire pour fracture de la hanche entre le 1er janvier 2012 et le 31 décembre 2016. Les patients ont été stratifiés selon la stratégie d'inversion choisie (vitamine K c. CCP). Les effets indésirables, le délai préopératoire, la durée du séjour hospitalier et la mortalité ont été recueillis à partir des dossiers médicaux électroniques et ont été comparés entre les 2 groupes de l'étude et un groupe témoin non sous AVK. Résultats: En tout, 141 patients ont été inclus dans l'étude, 65 dans le groupe sous vitamine K, 26 dans le groupe sous CCP et 50 dans le groupe témoin. Le délai préopératoire médian pour le groupe sous CCP (20 h [éventail interquartile (ÉIQ)] 13­25 h]) et le groupe témoin (20 h [ÉIQ 15­33 h]) a été plus bref que pour le groupe sous vitamine K (45 h [ÉIQ 31­52 h]) (p < 0,001). Les patients du groupe sous CCP ont eu un séjour hospitalier médian plus bref que les patients du groupe sous vitamine K (6 j [ÉIQ 4­9 j] c. 8 j [ÉIQ 6­11 j]) (p < 0,05). Aucune différence n'a été observée quant à la proportion de patients ayant reçu une transfusion de culot globulaire ou ayant manifesté des complications thrombotiques ou hémorragiques. Aucune différence quant à la mortalité à 12 mois n'a été observée entre les groupes. Conclusion: Chez les patients atteints d'une fracture de la hanche, l'utilisation des CCP plutôt que de la vitamine K pour inverser l'effet des AVK a significativement abrégé le délai préopératoire et la durée du séjour hospitalier, et n'a pas été associée à une augmentation des taux de complications thrombotiques ou hémorragiques. Des études prospectives sur un plus grand nombre de patients sont nécessaires pour confirmer ces résultats prometteurs.

Metasul vs Cerasul bearings: a prospective, randomized study at a mean eighteen years.

BACKGROUND: The aims of our study were to compare the clinical, radiographic outcomes and survivals between second-generation metal-on-metal (Metasul) and ceramic-on-ceramic (Cerasul) bearings at a very long-term follow-up. METHODS: A prospective, randomized study was originally performed on a consecutive series of 250 cementless, 28-mm head and primary total hip arthroplasties between 1999 and 2002. For each bearing (Metasul or Cerasul), 125 THAs were initially included. All cases were evaluated both clinically and radiographically, and survival was assessed, considering revisions for aseptic loosening or for any reason as the end points for failure. RESULTS: At a mean 18-year follow-up, clinical and radiographic outcomes were similar. Harris Hip Score increased 30% in the Metasul group and 32% in the Cerasul group (p = 0.6). Survival free of aseptic loosening was higher for Cerasul (100%), than for Metasul (94% [CI 88-99.9]) (p = 0.04). Survival free of any revision was 91% ([CI 84-98%]) for Cerasul and 91% ([CI 84-98%]) for Metasul. Fractures of Cerasul insert occurred in four cases (3%) at a mean 12.5 ± 3.3 years (range, 6 to 17 years). CONCLUSION: At 18 years, Cerasul demonstrated higher survivorship than Metasul considering aseptic loosening as an end point. However, Cerasul liners had high rate of fracture because of its sandwich design (thin ceramic liner into polyethylene). These implants are no more available on the market.

Molecular pathology of total knee arthroplasty instability defined by RNA-seq.

Total knee arthroplasty (TKA) is a durable and reliable procedure to alleviate pain and improve joint function. However, failures related to flexion instability sometimes occur. The goal of this study was to define biological differences between tissues from patients with and without flexion instability of the knee after TKA. Human knee joint capsule tissues were collected at the time of primary or revision TKAs and analyzed by RT-qPCR and RNA-seq, revealing novel patterns of differential gene expression between the two groups. Interestingly, genes related to collagen production and extracellular matrix (ECM) degradation were higher in samples from patients with flexion instability. Partitioned clustering analyses further emphasized differential gene expression patterns between sample types that may help guide clinical interpretations of this complication. Future efforts to disentangle the effects of physical and biological (e.g., transcriptomic modifications) risk factors will aid in further characterizing and avoiding flexion instability after TKA.

Quadriceps Snip in 321 Revision Total Knee Arthroplasties: A Safe Technique in a Matched Cohort Study.

BACKGROUND: Quadriceps snips (QSs) are commonly used to gain enhanced exposure during revision total knee arthroplasties (TKAs). The goals of this study were to evaluate the longer-term clinical outcomes and complications in a contemporary cohort of patients treated with QS and to compare them to a matched cohort treated with standard exposure during revision TKAs. METHODS: We retrospectively identified 3107 revision TKAs performed at our institution between 2002 and 2012. QS was performed in 321 of these knees. Each QS revision TKA was 1:1 matched to a control (standard exposure) based on age, gender, body mass index, surgery date, and reason for revision. Clinical outcomes studied included Knee Society Score, range of motion, and extensor lag. Other outcomes assessed were complications (especially extensor mechanism disruption) and survivorship. Mean follow-up was 5 years. RESULTS: The mean Knee Society Score improvement was not significantly different between groups (P = .9). At latest follow-up, the mean range of motion was 93° in the QS group and was slightly higher at 100° in the control group (P = .002). Postoperative extensor lag of 10 degrees or more was present in 21 (6.7%) QS knees versus 19 (6.8%) control knees (P = .95). Complication rates were similar in both groups with extensor mechanism disruption occurring in 3 in the QS group (0.7% at 10 years) versus 4 in the control group (0.8% at 10 years; P = .91). Kaplan-Meier survivorships free of revision for aseptic loosening, free of any revision, and free of any reoperation were similar at 10 years (85%, 71%, and 61%, respectively, in the QS group vs 89%, 70% and 60%, respectively, in the control group). CONCLUSION: This matched cohort study is the largest to report the results of QS and also the largest to report results compared with patients treated with standard exposure. Building on the results of smaller historical series, this study demonstrates QS was a facile technique in complex revision TKAs allowing for safe exposure with few complications. LEVEL OF EVIDENCE: III (case-control study).

Long-term survivorship of a monoblock long cementless stem in revision total hip arthroplasty.

PURPOSE: The purpose of this study was to assess the clinical outcomes, complications, and survival of a long cementless titanium femoral stem in revision total hip arthroplasty (THA) at a minimum five year follow-up. METHODS: Between 2000 and 2010, 114 patients (116 hips), with a mean age of 68 ± 12 years, underwent revision THA using a KAR® stem (DePuy, Leeds, UK). The main reasons for revision were aseptic loosening (82%), periprosthetic joint infections (PJI) (11%), and periprosthetic fractures (6%). Mean follow-up was ten ± three years (range, 5-16). Harris Hip Score (HHS), Oxford Hip Score (OHS), and Postel-Merle d'Aubigné (PMA) score were recorded. Radiographic analysis assessed stem osseointegration and subsidence. Survival was analyzed using the Kaplan-Meier (KM) method and cumulative incidence function (CIF). RESULTS: Post-operative HHS was 83 ± 15 (range, 35-99) and OHS was 37 ± 8 (range, 8-48). PMA score significantly increased from 12 ± 2 (range, 5-18) pre-operatively to 14.6 ± 2 (range, 9-18) post-operatively (p = 0.0004). The radiographic Engh score was 15 ± 8 (range, 7-22). Stem subsidence was observed in two cases (3%). At ten years, five stems had been revised, three for infections and two for periprosthetic fractures. Using the KM method, ten year survival free of stem revision for aseptic loosening was 100%, free of revision for any reason 95%, and free of any re-operation 81%. CONCLUSIONS: The present study reported satisfactory outcomes and survival of a long tapered unlocked cementless femoral stem in revision THA at a minimum follow-up of five years.

A comparative study about the incidence of dislocation and peri-prosthetic fracture between dual mobility versus standard cups after primary total hip arthroplasty.

PURPOSE: Dislocation and peri-prosthetic fracture (PPF) are major reasons for revision THA (total hip arthroplasty). The main advantage of dual mobility (DM) cups is to minimize the incidence of dislocation compared to single mobility (SM) cups. We hypothesized that the use of DM would lead to an increased risk of PPF because of its greater stability. In contrast, standard cups would be at higher risk of dislocation. METHODS: A retrospective comparative study was performed in our institution including 126 revision THAs between January 2013 and December 2017. Collected data included gender, age, BMI, Parker score, ASA score, the etiology for primary THA, type of cup (SM or DM), cortical index, Noble index, and the stem fixation. RESULTS: Overall, 53 standard and 73 DM cups were included for study. In the dislocation group, 29 had standard cups (83%) and 6 had DM cups (17%). Dislocation was 12-fold higher in SM cups (p < 0.001). In the PPF group, 24 had standard cups (26%) and 67 had DM cups (74%). PFF was 12-fold higher for DM cups (p < 0.001). A higher Parker score and a higher cortical index had a protective effect on the risk of PPF (OR = 0.76 (p = 0.03), OR = 0.57 (p = 0.048)). CONCLUSION: The use of DM increased hip stability but led to a higher rate of PPF by load transfer on the femur. Further studies with larger cohort and follow-up are needed to confirm these findings and measure the incidence of these complications.

The history of anatomy teaching in Lyon University: in the footsteps of Rabelais, Petit, Lisfranc, Testut and Latarjet, and many others.

Anatomy and Lyon have a very long history together since the first hospital in France was set up on the banks of the Saône River in the fourteenth century. The Lyon school of Anatomy was originally in the Hôtel-Dieu, which later housed the "secondary" (1821) then "preparatory" (1841) schools. Only in 1877 was the Medicine and Pharmacy Faculty set up. The development of anatomy teaching followed the rise of printing in the fifteenth century. The rise of surgery was founded on knowledge of anatomy and the ability to teach it. Before the days of anesthesia, surgery required perfect anatomical skills, to keep operative time to a minimum. Correlation with anatomy accompanied the introduction of radiology and later of medical imaging in general; the science of Anatomy is nowadays enriched by robotics and information technology.

Prior Knee Arthroscopy Does Not Influence Long-Term Total Knee Arthroplasty Outcomes and Survivorship.

BACKGROUND: Arthroscopic knee surgery frequently precedes total knee arthroplasty (TKA). There have been mixed data on the effect of prior arthroscopic surgery on results of TKA. The purpose of this study was to compare the 10-year Knee Society Score (KSS), survivorship, and complications of TKA in a cohort of patients who had a previous knee arthroscopy to a control cohort. METHODS: A retrospective review of 1315 TKAs who underwent a primary TKA between 2003 and 2004 was performed. Of these, 160 TKAs had previous arthroscopy (excluding ligamentous reconstruction). A matched cohort study 2:1 was carried out with a group of 320 controls (no prior surgery). Outcomes were assessed with the original KSS, range-of-motion, complications, and survivorships. Mean follow-up was 9 years. RESULTS: The mean KSS increased from 36-84 in the arthroscopy group vs 35-86 in the control group (P = .5). The mean preoperative and postoperative range-of-motion was not different between groups (P = .2). The survivorship free of complication at 5 years was similar in both groups (94.3% in arthroscopy group vs. 95.3% in the control; P = .7) with infection in 2 controls and 3 arthroscopy cases (P = .2). The survivorships free of revision for aseptic loosening, revision for any reason, and reoperation were similar at 10 years (96.5%, 94.6%, and 89.2%, respectively, in the arthroscopy group vs 96.2%, 95.9%, and 91.5% in the control group). CONCLUSION: There were no significant differences between both groups. These data are reassuring and valuable in an era in which many candidates for TKA will have had previous arthroscopic knee surgery.

Seasonality of Periprosthetic Femur Fractures in 12,700 Primary and Revision Total Hip Arthroplasties.

BACKGROUND: Periprosthetic femur fractures after primary and revision total hip arthroplasty (THA) are one of the most common long-term reasons for reoperation after THA. Previous investigations have analyzed the incidence and risk factors of these fractures. No previous study, however, has analyzed a variation in periprosthetic femur fractures between meteorologic seasons. The aim of this study was to compare the incidence of periprosthetic femur fractures after primary and revision THAs depending on the meteorologic season. METHODS: We identified 8920 patients (10,672 hips) who underwent primary THAs and 1830 patients (1998 hips) who underwent revision THAs at our institution between 1995 and 2011. All patients resided in the Upper Midwest at the time of surgery. Patients who experienced periprosthetic femur fractures were identified and categorized based on the meteorologic season. A Cox model was used to assess the association of seasonality with the risk of fracture. RESULTS: During the study period, 165 primary THAs and 80 revision THAs sustained a periprosthetic femur fracture. Using winter as a reference, the risk of a periprosthetic femur fracture after primary THA was not statistically higher in the spring (hazard ratio [HR] = 1.3; P = .2), autumn (HR = 1.4; P = .2), and summer (HR = 1.415; P = .1). Similarly, the risk of periprosthetic femur fracture after revision THA was not statistically higher in the spring (HR = 0.9; P = .6), autumn (HR = 0.6; P = .1), and summer (HR = 0.9; P = 1.0). CONCLUSION: The risk of periprosthetic femur fracture after primary and revision THA does not significantly differ between meteorologic seasons.

Dual mobility cups in revision total hip arthroplasty.

AIM: The purpose of our study was to evaluate the dislocation and aseptic loosening rates of a dual mobility construct in revision total hip arthroplasty (THA). METHODS: Three hundred thirty-four revision THAs performed between 2006 and 2011, using a dual mobility cup, were included in this retrospective study. The indications for revision were aseptic loosening (70%), infection (21%) and recurrent instability (9%). The minimum follow-up was five years (mean 7 ± 2 years, maximum 10 years). RESULTS: At the latest follow-up, 11 episodes of dislocation occurred, seven of which were recurrent (1.3% for aseptic loosening, 2.8% for infection and 3.4% for recurrent dislocation). Ten cases of aseptic loosening occurred; in seven of them, a cemented cup into a reinforcement ring had been used (OR = 14, p = 0.0001). CONCLUSION: This study provided evidence of the advantages of dual mobility cups in all revision THA indications.

The AES total ankle arthroplasty analysis of failures and survivorship at ten years.

BACKGROUND: AES mobile-bearing total ankle replacement was developed from the Buechel Pappas model. It was withdrawn in 2009, after identification of a higher than expected complication rate. The purpose of the current study was to analyse clinical outcomes, failures and survival of the initial series of 50 AES published in 2009. METHODS: In this single-centre continuous prospective study (2003-2006), 50 AES prostheses were included. Pre-operative osteoarthritis was mainly post-traumatic (50%) and secondary to instability (36%). All patients were assessed with clinical and radiographic follow-up at six months, one year, two years and every two to three years thereafter. A CT-scan was systematically performed before procedure, and at two years, five years and ten years. At last follow-up, all patients with TAR had a functional (SF 36, AOFAS) and clinical assessment. All complications or surgical events were analysed. RESULTS: The mean follow-up was ten ± two years (range, 9-13). The mean AOFAS score was 75 points (range, 26-100). The mean SF 36 score was 69 points (range, 35-97). There was a significant deterioration in AOFAS score at five years and at last follow-up (p < 0.05). Fifteen TARs underwent reoperation for cyst curettage-graft because of development of periprosthetic lesions. Six of them ended up with prosthesis removal-arthrodesis. At the last follow-up, 14 TARs were removed for arthrodesis. Of the 30 prostheses seen at last follow-up, four are awaiting prosthesis removal-arthrodesis and one for cyst curettage-graft. The ten year survivorships free of any prosthesis removal or arthrodesis and free of any reoperation were 68% (95% CI, 55-85) and 57% (95% CI, 44-74), respectively. CONCLUSION: Our data suggested a high rate of reoperation. Overall ten year survival was lower than with other designs, particularly due to cyst lesions. LEVEL OF EVIDENCE: Level IV, prospective case series.

Prospective longitudinal study of one hundred patients with total hip arthroplasty using a second-generation cementless dual-mobility cup.

PURPOSE: The aim of our study was to assess the radio-clinical results, mid-term survivorship and dislocation rate of a new-generation dual-mobility cup. METHODS: The first 100 patients (104 primary total hip arthroplasties) who were implanted with a new-generation cementless dual-mobility cup (Sunfit TH, Serf, Décines) were included in our study, with a minimum follow-up of five years. RESULTS: Average follow-up was six years ± 0.44 (5-7). At last follow-up, the Harris and PMA scores were significantly improved, from 56 to 94 and 13 to 17 respectively (p < 0.001). No radiolucent line could be observed. There were no cases of prosthetic or intraprosthetic dislocation in our series. Survivorship without cup loosening as the endpoint was 100 %. CONCLUSIONS: This study confirmed the interest of dual mobility in preventing prosthetic hip dislocation. Intraprosthetic dislocation is a complication that seems to have been resolved in the mid-term follow-up.

Periprosthetic osteolysis after AES total ankle replacement: Conventional radiography versus CT-scan.

BACKGROUND: The aim of this study was to compare conventional X-rays and CT-scan in detecting peri-prosthetic osteolytic lesions, a major concern after total ankle replacement (TAR). METHODS: We prospectively assessed 50 patients (mean age 56 years), consecutively operated on by the same senior surgeon, between 2003 and 2006 and with a mean follow-up period of 4 years (range, 2-6.2). The component used was AES total ankle replacement. The etiologies for total ankle arthroplasty were: posttraumatic in 50%, osteoarthritis secondary to instability in 36%. Plain radiographs were analyzed by 4 independent observers, using a 10-zone protocol (location) and 5 size categories. RESULTS: At 4-year follow-up, all patients had been CT-scan assessed with the same protocol by 2 independent observers. Plain radiographs showed dramatic progression of severe periprosthetic lyses (>10mm): from 14% to 36% of interface cysts for the tibial component respectively at 2 and 4-year follow-up and from 4% to 30% for the talar implant. The talar component was more accurately assessed by CT-scan (mean frontal and sagittal talar lesion: from 270 mm2 to 288 mm2 for CT-scan versus 133 mm2 to 174 mm2 for X-rays). For tibial cysts, axial views showed larger lesions (313 mm2 than frontal (194 mm2) or sagittal (213.5 mm2) views. At 4-year follow-up, 24% of patients had revision with curetage or arthrodesis, and at 7 years follow-up 38% were revised. CONCLUSION: These results are similar to recent AES series, justifying withdrawal of this device. CT-scan was more accurate than X-rays for detecting and quantifying periprosthetic osteolysis. We recommend a yearly radiological control and CT-scan in case of lesion on X-rays.

Anatomical study of the medial patello-femoral ligament: landmarks for its surgical reconstruction.

PURPOSE: The aim of this dissection study was to describe the anatomical insertions of the medial patello-femoral ligament (MPFL), and to assess its relationship with surrounding structures to improve its surgical reconstruction. METHODS: Twelve knees (7 cadavers) were included for the study. Measurements and general features of the MPFL were assessed: lengths, widths and insertions. RESULTS: The MPFL was found in all knees, presenting a triangular shape, and extending from the medial part of the patella to its femoral insertion (its length was of 59 ± 6.6 mm), distal to the adductor tubercle. The mean femoral insertion of the MPFL was 7.2 ± 2.7 mm proximal and 7.4 ± 4.0 mm posterior to the medial femoral epicondyle (MFE). It was also at a mean 11 ± 2.8 mm distal and 1.3 ± 2.1 mm posterior to the adductor tubercle, and 22 ± 6.4 mm anterior to the posterior condyle. We did not find any double-bundle organization on the patellar insertion. The width of the MPFL was 8.8 ± 2.9 mm at the femoral insertion, 27 ± 5.9 mm at the patellar insertion, and 12 ± 3.1 mm in the middle of the MPFL. The vastus medialis obliquus was found to be inserted on the superior part of the MPFL. CONCLUSION: The adductor tubercle appeared to be a better landmark than the MFE for the femoral tunnel positioning during surgical reconstructions of the MPFL because it was easier to identify and its relationship with the femoral insertion of the MPFL was constant (10 mm below).