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PURPOSE: This study aimed to compare the position of the patella at 90° of flexion before and after implantation of two TKA models with identical tibiofemoral geometry but different trochlear and patellar designs. The hypothesis was that the design with the deeper 'anatomic' trochlea could produce more natural patellar positions. METHODS: Intra-operative navigation data were collected from 22 consecutive cases that received two TKA designs (9 HLS Noetos(®) and 13 HLS KneeTec(®)). Both implants were cemented postero-stabilised TKAs with mobile tibial inserts and patellar resurfacing. Operations were guided by a non-image-based system that recorded relative femoral, tibial and patellar positions pre- and post-operatively. RESULTS: The two groups exhibited little difference in femoral internal-external rotation and anterior-posterior translation during knee flexion. The two groups exhibited significant differences in patellar position at 90° of flexion. Post-operatively, the patella was similarly shifted medially relative to the femur (Noetos 6.9 mm, KneeTec 6.0 mm, n.s.). Patellar flexion was equivalent in native knees (Noetos 18.3°, KneeTec 20.5°, n.s.), but in implanted knees, it was considerably different (Noetos 6.3°, KneeTec 23.5°, p = 0.031). CONCLUSIONS: The present study compared intra-operative navigation data from two patient series that received TKA implants with identical tibiofemoral articular geometry but different patellofemoral designs. The results confirm that tibiofemoral kinematics are unchanged, but that patellar positions at 90° of flexion offer greater mechanical advantage to the quadriceps using the KneeTec than using the Noetos. The findings raise awareness of influence of patellofemoral geometry on mid-flexion kinematics and help surgeons select the most suitable implant for patients with weak quadriceps muscles or with history of patellar instability. LEVEL OF EVIDENCE: Comparative study, Level III.

Objectifs (1) Evaluer a moyen terme les resultats fonctionnels des reparations arthroscopiques des ruptures massives de la coiffe des rotateurs et (2) determiner les facteurs pronostiques influencant les resultats. Materiel et methodes A partir d’une serie continue de 525 reparations arthroscopiques de la coiffe des rotateurs, nous avons analyse retrospectivement les resultats de 73 patients traites pour rupture massive. Le recul moyen etait de 41 mois (29–55) et les resultats fonctionnels ont ete analyses avec le score de Constant (CS) et le « Subjective Shoulder Value » (SSV). Une analyse multivariee a ete realisee pour determiner si les resultats fonctionnels etaient influences par le nombre de tendons rompus, l’infiltration graisseuse musculaire preoperatoire et par la reparabilite operatoire. Resultats Le CS median etait augmente de 34 a 81 points ( p n = 33) et antero-superieures (85, n = 13) que pour les ruptures a 3 tendons (74, n = 27) ( p n = 28) que pour les stades 2 (78, n = 34) ( p n = 11) ( p = 0,04). Les scores de Constants n’etaient que legerement superieurs en cas de reparations tendineuses completes (81,5, n = 50) comparees aux reparations partielles (79, n = 23) ( p = 0,11). L’analyse echographique a mis en evidence une cicatrisation tendineuse incomplete dans 10 des 50 cas repares integralement et dans 11 des 23 cas repares partiellement. Conclusions Nos resultats fonctionnels a moyen terme sont comparables a ceux de la litterature recente et confirment le benefice significatif des reparations arthroscopiques des ruptures massives de la coiffe des rotateurs, meme partielles. Alors que les resultats fonctionnels absolus sont superieurs pour les ruptures de 2 tendons, le benefice relatif des reparations des ruptures de 3 tendons est equivalent et permet aux patients d’obtenir un resultat tres satisfaisant et de retrouver leur autonomie.

The design of the trochlear compartment is crucial in patellofemoral arthroplasty (PFA), because 78% of patients with isolated patellofemoral arthritis present concomitant trochlear dysplasia with patellar maltracking and therefore remain predisposed to post-operative patellar subluxation and dislocation. The study investigated whether current PFA implants are designed with anatomic trochlear parameters such as the sulcus angle, lateral facet height and groove orientation.Five trochlear components of commercially available PFA implants were scanned, and the generated three-dimensional surfaces were measured using engineering design software. The mediolateral trochlear profiles were plotted at various flexion angles (0°, 15°, 30° and 45°) to deduce the following variables: sulcus angle, height of lateral facet and trochlear groove orientation.Four specimens had sulcus angle144° in the 45° of flexion, and all five specimens had sulcus angle143° in 30° of flexion. Three specimens had a facet5 mm high through the entire range of early flexion (0°-30°), and two specimens had a facet5 mm high beyond early flexion (30°-45°). The trochlear groove was oriented laterally in all specimens (range 1.6°-13.5°).Current PFA trochlear components are not always designed with anatomic parameters, and some models exhibit characteristics of trochlear dysplasia. Surgeons are therefore advised to implant components with a deep sulcus, particularly in patients with history of patellofemoral disorders, and to adapt the surgical technique and extensor mechanism if the component implanted has a shallow sulcus, to ensure normal patellar tracking.III.

PURPOSE: The goal of this study was to compare the kinematics of knees before and after total knee arthroplasty (TKA) that relies on an inter-condylar 'third condyle'. The hypothesis was that the 'third condyle' provides sufficient flexion stability and induces a close to normal femoral rollback, thus granting natural joint kinematics. METHODS: Intra-operative navigation data were collected from 29 consecutive cases that received a cemented TKA (HLS Noetos, Tornier SA, France) designed with an inter-condylar 'third condyle' that engages within the tibial insert beyond 35° flexion. Operations were guided by a non-image-based system (BLU-IGS, Orthokey Italia srl, Italy) that recorded relative femoral and tibial positions in native and implanted knees during: passive range of motion, anterior drawer test at 90° flexion, and varus-valgus stress tests at full extension and at 30° flexion. RESULTS: The total internal tibial rotation during flexion was similar for native (8.2 ± 4.2°) and implanted knees (8.0 ± 5.4°). The lateral femoral condyle was more posterior in implanted knees (1.2 ± 9.4 mm) than in native knees (9.5 ± 3.6 mm) throughout early flexion (p < 0.01), but this difference diminished beyond 100° flexion (n.s.). The implanted knees did not exhibit paradoxical external tibial rotation. Varus-valgus laxity in full extension was lower for implanted knees than for native knees (p = 0.0221), but at 30° flexion was almost identical for both native and implanted knees. Anteroposterior laxity was similar in implanted and native knees. CONCLUSIONS: The 'third condyle' TKA provides similar anteroposterior and mediolateral stability to the natural knee. This feature granted an adequate balance between laxity and constraint to reproduce natural joint kinematics, including smooth femoral rollback, without causing paradoxical external tibial rotation.

Anterior knee pain (AKP) is observed in total knee arthroplasty (TKA) both with and without patellar resurfacing, and neither patellar denervation nor secondary resurfacing are effective for treating the symptoms. The exact causes for pain remain unclear, though abnormal patellofemoral forces due to patellar malalignment or inadequate implant design can play an important role. The purpose of this study was to arthroscopically evaluate patellofemoral congruence after wound closure following TKA without patellar resurfacing and correlate it to patellar morphology and postoperative pain and function.The authors prospectively studied 30 patients that received uncemented mobile-bearing TKA. Patellofemoral congruence was assessed arthroscopically after wound closure by estimating the contact area between the native patella and the prosthetic trochlea (two-thirds,one-third,one-third). The findings were correlated to preoperative assessments of patellar geometry (Wiberg classification using X-rays) and clinical outcomes [Knee Society Score (KSS), AKP on Visual Analogic Scale (VAS), and patient satisfaction].Knees of 22 women and 8 men aged 69.8 years (range, 61-84 years) were analyzed at 16 months (range, 12-23 months). Preoperative patellar geometry was Wiberg type A in 11, type B in 12 and type C in 7 knees. Postoperative KSS was 79.1 (range, 50.0-94) and the VAS for AKP was 1.6±1.3 (median, 1; range, 0-5). Patellar congruence was correlated with patellar morphology (P0.001) but not correlated with any clinical outcomes (KSS, VAS or satisfaction). There were also no statistical correlations between patellar morphology or patellofemoral congruence and patient characteristics.While patellar morphology and patellofemoral congruence are strongly related, they are not associated with clinical outcomes or patient demographics. Considering that numerous incongruent patellofemoral joints were pain-free, and conversely, many perfectly congruent patellofemoral joints had anterior pain, the authors suppose that pain is probably caused by mechanisms other than patellofemoral pressures.

Background: Osteoconductive additives are used in resorbable interference screws for anterior cruciate ligament (ACL) reconstruction to improve graft incorporation and mitigate adverse effects. There are no published studies that compare biological performances of bioresorbable and biocomposite screws without artifacts due to different follow-up times and intrinsic patient characteristics. Purpose/Hypothesis: The purpose of this study was to evaluate the efficacy of osteoconductive agents in bioresorbable screws for ACL reconstruction at minimum follow-up of 2 years by intrapatient comparison. The hypothesis was that osteoconductive ceramics would result in slower resorption, improved ossification, and less tunnel widening. Study Design: Cohort study; Level of evidence, 2. Methods: A total of 28 ACL reconstructions at 2 centers were randomly assigned into 2 comparable groups: (1) the graft was fixed in the tibia using standard bioresorbable screws and in the femur using biocomposite screws with osteoconductive agents (biphasic calcium phosphate), and (2) the graft was fixed in the femur using a standard bioresorbable screw and in the tibia using a biocomposite screw with osteoconductive agents. Results: Twenty-seven patients completed evaluations at 29.9 ± 4.0 months. Resorption was complete for more bioresorbable (81%) than biocomposite (37%) screws ( P = .0029), whereas satisfactory ossification was observed in more biocomposite (52%) than bioresorbable (15%) screws ( P = .0216). The tunnel shape was normal in more biocomposite (81%) than bioresorbable (48%) screws ( P = .0126), and marked cortical formation was twice more frequent for biocomposite (78%) than bioresorbable (37%) screws ( P = .0012). Bioresorbable screws exhibited faster resorption in the femur ( P = .0202) but not in the tibia (not significant). Conversely, biocomposite screws demonstrated better ossification, less tunnel widening, and more cortical formation in the tibia ( P < .0001, P = .0227, and P < .0001, respectively) but not in the femur (not significant for all). Conclusion: Osteoconductive additives can reduce the extent of resorption while improving ossification, reducing tunnel widening, and increasing cortical formation. Clinical Relevance: The benefits of osteoconductive agents justify their associated costs for ACL reconstruction, particularly in the tibia.

Introduction La litterature confirme l’interet des mesures laximetriques dans le diagnostic des ruptures du ligament croise anterieur (LCA). D’autres facteurs influencant ces mesures n’ont pas ete evalues. Le but de cette etude est d’evaluer la relation entre la pente tibiale, la laximetrie et les lesions meniscales dans les ruptures du LCA. Patients et methode Une etude prospective monocentrique de 185 patients operes d’une rupture du ligament croise anterieur a ete realisee entre janvier et juillet 2014. Les criteres d’inclusion etaient les ruptures du LCA a l’exception des lesions multi-ligamentaires et des lesions du LCA associees a une arthrose. Ont ete mesure la pente tibiale posterieure, la translation tibiale anterieure sur des radiographies de profil en appui monopodal a 20° et sur des radiographies dynamiques a 15 kg. Le bilan meniscal de reference etait etabli au moment de l’intervention. Resultats L’âge operatoire moyen etait de 30 ± 10 ans ; 7,6 % des patients avaient une rupture iterative du LCA. La translation tibiale anterieure moyenne etait de 3 ± 3 mm en appui monopodal et de 10 ± 4 mm aux radiographies dynamiques. La translation tibiale du genou controlateral etait de 4 ± 3 mm. Le differentiel moyen etait de 6 ± 4 mm. La pente tibiale moyenne etait de 10,0 ± 3° et la pente controlaterale de 9,5 ± 3°. Cette difference etait significative (Wilcoxon p = 0,001). La valeur de la pente tibiale etait correlee a la translation tibiale anterieure en appui monopodal (Spearman r = 0,35, p Discussion/conclusion La mesure de la pente tibiale confirme les donnees de la litterature – la pente tibiale est augmentee chez les patients operes d’une rupture du LCA par rapport a la population normale. Il existe une correlation nette entre la pente tibiale et la translation tibiale anterieure, a la fois sur les radiographies en appui monopodal, et sur les radiographies dynamiques. La laximetrie est un bon moyen de quantifier la laxite anterieure du genou et peut egalement etre un element predictif de lesions meniscales mediales associees.

Malgre l’efficacite reconnue de l’echographie pour le diagnostic et le suivi des pathologies de la coiffe des rotateurs, il n’existe pas de classification echographique pour le suivi des ruptures de coiffe. Cette etude avait pour objectif de valider une classification echographique developpee a partir de la classification IRM existante pour le suivi des reparations arthroscopiques de la coiffe des rotateurs. De janvier 2007 a juin 2010, 257 patients presentant une rupture complete de la coiffe ont ete inclus. La reparation a ete effectuee selon une technique en double rang. Les scores de Constant, UCLA et SSV ont ete utilises pour le suivi clinique. Un controle echographique a ete realise par un radiologue specialise a 3,6 et 12 mois postoperatoires selon un protocole predefini. Une evaluation a distance par le meme radiologue reunissant les criteres IRM decrits par Sugaya et al. a ete realisee en vue de la classification echographique en 5 stades. Stade I pour des tendons de plus de 2 mm d’epaisseur et d’echostructure normale, stade II pour une modification de l’echostructure, stade III pour un amincissement du tendon (

Summary Background Rotation of tibial component has not been analysed in literature for unicompartmental knee arthroplasty. The purpose of the study was to determine and compare the rotation of medial and lateral unicompartmental knee arthroplasty (UKA) tibial components. We assumed both components (lateral and medial) were positioned with external rotation. Material and methods Eighteen lateral and 19 medial UKA patients were scanned postoperatively in neutral position with computed tomography enabling lower extremity three-dimensional image acquisition from the hip to the ankle. All the patients were operated by three different senior surgeons using the same surgical technique. From the reconstructions we measured the two-dimensional (2D) rotation of the tibial components. Results The rotation of the tibial component was external (mean 6.5°, SD 5.1°) for the medial UKA and external (mean 7.3°, SD 10.3°) as well for the lateral UKA. The difference was statistically insignificant (p = 0.717). Discussion This study presents the first 2D in vivo analysis accurately determining and comparing medial and lateral UKA component rotation. Despite a wide range of value, we found both components were indeed externally rotated. The variability in implant positioning was observed despite the rigorous performance of an experienced surgeon using routine techniques in patients selected under routine criteria. Further analysis of these patients for satisfaction and implant survivorship in relation to implant rotation may give us an optimal range for the tibial component. If it is found that this ideal range cannot be consistently obtained with current surgical techniques then there may be a case for the use of a navigation system. Level of evidence Level IV Retrospective study.