Less risk of conversion to total knee arthroplasty without significant clinical and survivorship difference for opening-wedge high tibial osteotomies in varus knee deformities at 10-year minimum follow-up compared to closing-wedge high tibial osteotomies.

PURPOSE: The purpose of this study was to evaluate the clinical outcomes and survivorship at minimum 10-year follow-up of patients undergoing primary valgisation high tibial osteotomy (HTO) for medial osteoarthritis (OA), treated by Opening-Wedge HTO (OW-HTO) or Closing-Wedge HTO (CW-HTO). METHODS: This was a retrospective cohort study of consecutive patients presenting to a single institution undergoing HTO for isolated medial compartment OA. Two hundred and twenty three HTOs for isolated medial tibio-femoral OA were performed between January 2002 and December 2010. Patients were eligible if they had minimum 10-year follow-up and received either a CW or OW-HTO. Fifteen (6.7%) patients died and twenty-five (11.2%) were lost to follow-up. One hundred and eighty three (82.1%) patients were included in the final analysis and divided into two groups: OW-HTO (96/183; 52.4%) and CW-HTO (87/183; 47.6%). Range of motion, KSS, KOOS scores, and conversion to TKA rate were analyzed between groups. Both groups were comparable regarding age, arthrosis stage, gender, ASA score and BMI at the time of HTO. Survival analysis was conducted with re-intervention for TKA as the end point. RESULTS: At the time of HTO, mean age was 55 years ± 7.9 (27-73.9) with 72.7% of patients being male. The mean follow-up was 13.3 years ± 2.7 (10-19). Sixty-four (34.9%) patients underwent TKA at a mean delay of 9.3 years ± 3 (3-16). The conversion to TKA rate was significantly higher in the CW-HTO group versus the OW-HTO group: 42.5% (37/87) versus 28.1% (27/96) (p = 0.04). The survival at 15-year follow-up was 59.2% in the OW-HTO group versus 54.6% in the CW-HTO group (n.s.). At 13-year follow-up, KSS Function score was significantly better in the OW-HTO (90.9 versus 82.4; p = 0.007). No significant difference was observed between the two groups regarding the KOOS score, KSS Knee Score and complication rate. CONCLUSION: At mean follow-up of 13 years, no significant clinical and survivorship difference was observed between the two groups. The conversion to TKA was significantly lower following OW-HTO. Minor correction was associated with risk of requiring subsequent TKA. LEVEL OF EVIDENCE: Retrospective case series, IV.

No significant clinical and radiological differences between fixed versus mobile bearing total knee replacement using the same semi-constrained implant type: a randomized controlled trial with mean 10 years follow-up.

PURPOSE: The aim of this study was to compare the long-term clinical and radiological results between fixed (FB) and mobile bearing (MB) implants with identical design from the same manufacturer. METHODS: From March 2007 to May 2009, we recruited 160 patients in a prospective, single centered, randomized controlled trial. The authors compared 81 FB total knee arthroplasty (TKA) versus 79 MB with medial compartment osteoarthritis. The same posterior stabilized HLS Noetos knee prosthesis (CORIN) was used in all patients. The two groups only differed by the tibial insert (fixed or mobile). The authors compared the postoperative Knee Society Score (KSS), the passive clinical and active radiological knee flexion, the implant survivorship, the complications, and the presence of radiolucent lines. RESULTS: At mean 10.5 years' follow-up (range 8-12.1 years) no significant differences were found in clinical scores (KSS (p = 0.54), pain score (p = 0.77), stair climbing (p = 0.44), passive maximum flexion (p = 0.5)) or for radiological analyses (maximum active radiological flexion (p = 0.06), presence of progressive radiolucent lines (5 (MB group) versus 6 (FB group); p = 0.75)) between groups. No significant difference was found in overall implant survivorship (82% (MB group) versus 78% (FB group) p = 0.58) or complication rate (p = 0.32) at the last follow-up. CONCLUSION: No significant clinical and radiological differences were found between fixed and mobile bearing TKA using the same semi-constrained implant type with comparable overall survivorship. The choice between a fixed or mobile bearing implant should be based on surgeon preference and experience with the selected implant. LEVEL OF EVIDENCE: Prospective randomized controlled trial, Level II.

Combined ACL reconstruction and opening wedge high tibial osteotomy at 10-year follow-up: excellent laxity control but uncertain return to high level sport.

PURPOSE: The purpose of this study was to report the long-term outcomes of a continuous series of patients who underwent simultaneous anterior cruciate ligament (ACL) reconstruction and opening wedge high tibial osteotomy (HTO) for varus-related early medial tibio-femoral osteoarthritis. It was hypothesized that this combined surgery sustainably allowed return to sport with efficient clinical and radiological results. METHODS: From 1995 to 2015, all combined ACL reconstruction (bone-patellar tendon-bone graft) and opening wedge HTO for anterior laxity and early medial arthritis were included. Clinical evaluation at final follow-up used Tegner activity score, Lysholm score, subjective and objective IKDC scores. Radiologic evaluation consisted in full-length, standing, hip-to-ankle X-rays, monopodal weight-bearing X-rays and skyline views. AP laxity assessment used Telos™ at 150 N load. Student's t test was performed for matched parametric data, Wilcoxon for nonparametric variables and Friedman test was used to compare small cohorts, with p < 0.05. RESULTS: 35 Patients (36 knees) were reviewed with a mean follow-up of 10 ± 5.2 years. The mean age at surgery was 39 ± 9. At final follow-up 28 patients (80%) returned to sport (IKDC ≥ B): 11 patients (31%) returned to sport at the same level and 6 (17%) to competitive sports. Mean subjective IKDC and Lysholm scores were 71.8 ± 14.9 and 82 ± 14.1, respectively. The mean decrease of the Tegner activity level from preinjury state to follow-up was 0.8 (p < 0.01). Mean side-to-side difference in anterior tibial translation was 5.1 ± 3.8 mm. Three patients were considered as failures. The mean preoperative mechanical axis was 4.2° ± 2.6° varus and 0.8° ± 2.7° valgus at follow-up. Osteoarthritis progression for medial, lateral, and femoro-patellar compartments was recorded for 12 (33%, p < 0.05), 6 (17%, p < 0.001), and 8 (22%, p < 0.05) knees, respectively. No femoro-tibial osteoarthritis progression was observed in 22 knees (61%). CONCLUSIONS: Combined ACL reconstruction and opening wedge HTO allowed sustainable stabilization of the knee at 10-year follow-up. However, return to sport at the same level was possible just for one-third of patients, with femoro-tibial osteoarthritis progression in 39% of cases. LEVEL OF EVIDENCE: III.

Early complications and causes of revision after rotating-hinge TKA.

INTRODUCTION: The use of rotating-hinge total knee arthroplasties (TKA), despite several developments in prosthetic design, remains controversial. Results as well as indications of these devices are still discussed in primary intention and for young patients. The aim was to analyze early complications and survival rate of rotating-hinge TKA in primary intention and for revisions. METHODS: A retrospective study included all the patients operated for primary or revision TKA procedure using a rotating-hinge TKA between 2015 and 2018. Clinical and radiological data were collected before surgery and then at a minimum follow-up of 1 year. The primary endpoint was the aseptic revision-free survival rate. Secondary endpoints were the overall survival rate, IKS scores, range of motion and patellar complications. RESULTS: Forty patients were included at an average follow-up of 18 months. Primary implantation was performed for 12 patients (30%), and revision for 28 cases (70%). At a mean follow-up of 18 months, only one implant was removed for a septic cause. The cumulative survival rate at 24 months was 95%. At final review, eight knees (20%) had been revised, five (12.5%) due to infection, two (5%) because of extensor mechanism failure, two (5%) for global stiffness. The objective and subjective IKS were significantly higher postoperatively in both primary and revision groups (p < 0.0001). Patellar height was significantly smaller after revision (p = 0.04), while ROM significantly improved in this group (p = 0.02). At final endpoint, one implant was removed for a septic cause. CONCLUSION: This rotating-hinge TKA provides satisfying clinical and functional outcomes in primary intentions and in revision cases. There was no implant-associated complication. The complication rate remains high for revision surgery cases, mostly due to previous joint infections and poor soft tissue quality causing extensor mechanism failure. A longer-term study should be conducted to confirm this trend.

Increased valgus laxity in flexion with greater tibial resection depth following total knee arthroplasty.

PURPOSE: Soft tissue balancing is of central importance to outcome following total knee arthroplasty (TKA). However, there are lack of data analysing the effect of tibial bone cut thickness on valgus laxity. A cadaveric study was undertaken to assess the biomechanical consequences of tibial resection depth on through range knee joint valgus stability. We aimed to establish a maximum tibial resection depth, beyond which medial collateral ligament balancing becomes challenging, and a constrained implant should be considered. METHODS: Eleven cadaveric specimens were included for analysis. The biomechanical effects of increasing tibial resection were studied, with bone cuts made at 6, 10, 14, 18 and 24 mm from the lateral tibial articular surface. A computer navigation system was used to perform the tibial resection and to measure the valgus laxity resulting from a torque of 10 Nm. Measurements were taken in four knee positions: 0° or extension, 30°, 60° and 90° of flexion. Intra-observer reliability was assessed. A minimum sample size of eight cadavers was necessary. Statistical analysis was performed using a nonparametric Spearman's ranking correlation matrix at the different stages: in extension, at 30°, 60° and 90° of knee flexion. Significance was set at p < 0.05. RESULTS: There was no macroscopic injury to the dMCL or sMCL in any of the specimens during tibial resection. There was no significant correlation found between the degree of valgus laxity and the thickness of the tibial cut with the knee in extension. There was a statistically significant correlation between valgus laxity and the thickness of the tibial cut in all other knee flexion positions: 30° (p < 0.0001), 60° (p < 0.001) and 90° (p < 0.0001). We identified greater than 5° of valgus laxity, at 90° of knee flexion, after a tibial resection of 14 mm. CONCLUSION: Increased tibial resection depth is associated with significantly greater valgus laxity when tested in positions from 30° to 90° of flexion, despite stability in extension. Greater than 5° of laxity was identified with a tibial resection of 14 mm. When a tibial bone cut of 14 mm or greater is necessary, as may occur with severe preoperative coronal plane deformity, it is recommended to consider the use of a constrained knee prosthesis.

Faster return to sport after robotic-assisted lateral unicompartmental knee arthroplasty: a comparative study.

INTRODUCTION: Unicompartmental knee arthroplasty (UKA) is frequently performed on active patients with symptomatic osteoarthritis who desire a quick return to sports. The aim of this study was to compare return to sport after lateral UKA performed by robotic-assisted and conventional techniques. MATERIALS AND METHODS: This retrospective study has assessed 28 lateral UKA (25 patients), 11 performed with robotic-assisted technique and 17 with conventional technique, between 2012 and 2016. The mean age was 65.5 and 59.5 years, with a mean follow-up of 34.4 months (range 15-50) and 39.3 months (range 22-68). Both groups were comparable pre-operatively. Sport habits and the details of the return to sports were assessed using University of California, Los Angeles Scale (UCLA) and direct questioning. RESULTS: Robotic-assisted surgical technique provided significantly quicker return to sports than conventional technique (4.2 ±1.8 months; range 1-6 vs 10.5 ± 6.7 months; range 3-24; p < 0.01), with a comparable rate of return to sports (100% vs 94%). The practiced sports after lateral UKA were similar to those done preoperatively, with mainly low- and mid-impact sports (hiking, cycling, swimming, and skiing). CONCLUSION: Robotic-assisted lateral UKA reduces the time to return to sports at pre-symptomatic levels when compared with conventional surgical technique. The return to sports rate after surgery is high in both groups. A long-term study would provide data on the prothesis wear in this active population. LEVEL OF EVIDENCE: Comparative retrospective study, Level III.

Hypoxia potentiates the BMP-2 driven COL2A1 stimulation in human articular chondrocytes via p38 MAPK.

OBJECTIVE: Since the biological effect of cartilage mediators is generally studied in a non-physiologic environment of 21% O2, we investigated the effects of a chronic hypoxia on the capability of articular chondrocytes to respond to one anabolic stimulation. DESIGN: Human Articular Chondrocytes (HACs) were cultured under hypoxia and stimulated with the chondrogenic growth factor BMP-2. The phenotype of the chondrocytes was studied by RT-PCR, and the cartilage-specific type II collagen production and deposition were also examined by western immunoblot and immunofluorescence. The Bone Morphogenetic protein (BMP) signalling pathway was also analysed. RESULTS: BMP-2 is much more efficient to stimulate the expression of the cartilage-specific gene COL2A1 by HACs when cultured under hypoxia (1%O2) compared to normoxia (21%O2). Analysis of the BMP-activated signalling shows that the Smad pathway is inhibited under hypoxia, whereas p38 MAPK is activated, and is involved in a synergy between hypoxia and BMP signalling, thus contributing to the enhanced anabolic response. CONCLUSIONS: Our study shows that hypoxia interplays with a chondrogenic factor and enhances the overall anabolic activity of the HACs. Alternatively to Hypoxia-Inducible Factor (HIF) signalling, and through a cross-talk with the BMP signalling which involves the p38 pathway, hypoxic stimulation markedly increases the capability of chondrocytes to produce the cartilage-specific type II collagen. Therefore our study provides new evidences of the multilayered effects of hypoxia in the anabolic functions of chondrocytes. This understanding may help promoting the anabolic function of articular chondrocytes, and thus improving their manipulation for cell therapy.

The effect of lateral opening wedge distal femoral osteotomy on leg length.

PURPOSE: Varisation distal femoral osteotomy is a well-described treatment for lateral compartment arthrosis in the young, active patient. This treatment may potentially alter the length of the lower limb . The objective of this study was to quantify the change in leg length following lateral opening wedge distal femoral osteotomy using a blade plate. METHODS: Between 1998 and 2011, 29 lateral opening wedge distal femoral osteotomies were performed for symptomatic genu valgum with signs of lateral compartment arthrosis or patello-femoral symptoms. The mean age was 44.4 years (±11.3). Average follow-up was 80.2 months (±50.6). RESULTS: The mean osteotomy opening was 8.3° (±2.3). The femoro-tibial mechanical axis (mFTA) was improved significantly, from 187.8° (±3.5) to 180.4° (±2.6) post-operatively (p < 0.001). The pre-operative leg length discrepancy was -0.7 cm, compared to -0.6 cm post-operatively, which was not significant (n.s.). There were five revisions to arthroplasty for disease progression at meantime of 166.6 months post-operatively. The probability of survival at 60 months was 91.4% (95% CI 74.9-100%) with end-point of revision to total knee arthroplasty and 87.6% (95% CI 74.1-100%) of revision for complications. CONCLUSIONS: Lateral opening wedge distal femoral osteotomy, performed for symptomatic genu valgum, has no effect on leg length. This technique allows good correction of the axis of the lower limb; however, the complication rate is not insignificant (14%). Complications occurred mainly in post-traumatic cases and may be avoidable with attention to technique and optimum rehabilitation. The procedure should be reserved for young, active patients with significant symptoms. LEVEL OF EVIDENCE: IV.

The role of the meniscotibial ligament in posteromedial rotational knee stability.

PURPOSE: Tears of the posterior horn of the medial meniscus (PHMM) are very common in the ACL-deficient knee. Specific lesions of the PHMM have been described in the setting of ACL rupture: ramp lesions and injuries to the meniscotibial ligament. There are little data available regarding the role these lesions play in knee instability. The aim of this study is to analyse the biomechanical consequences of ramp and meniscotibial ligament lesions on knee stability. Our hypothesis was that these lesions would cause increased instability in the setting of ACL rupture. METHODS: A cadaveric study was undertaken: ten knees were included for analysis. The biomechanical repercussions of different meniscoligamentous injuries were studied in four stages: stage 1 involved testing the intact knee, stage 2 after transection of the ACL, stage 3 following creation of a ramp lesion, and stage 4 after detachment of the meniscotibial ligament. Four parameters were measured during the experiment: anterior tibial translation under a force of 134 N, internal and external tibial rotation under a torque of 5 Nm, and valgus angulation under a torque of 10 Nm. Measurements were taken in four knee flexion positions: 0° or full extension, 30°, 70°, and 90° of flexion. RESULTS: There was a statistically significant increase in anterior tibial translation for stage 2 (6.8 ± 1.3 mm, p ≤ 0.001), stage 3 (9.4 ± 1.3 mm, p ≤ 0.001), and stage 4 (9.3 ± 1.3 mm, p ≤ 0.001) compared to stage 1. There was no significant difference between stage 2 and stage 3 (2.6 mm, n.s.) or stage 4 (2.5 mm, n.s.). We did, however, demonstrate an increase in anterior tibial translation of 2.6 mm after the creation on a lesion of the PHMM compared to isolated division of the ACL, for all flexion angles combined. There was an increase in internal tibial rotation between stage 1 and stage 4 (3.2° ± 0.7°, p ≤ 0.001) and between stage 2 and stage 4 (2.0° ± 0.7°, p = 0.023). A significant difference was demonstrated for external rotation under 5 Nm torque between stages 4 and 1 (2.2° ± 0.5°, p ≤ 0.001) and between stages 4 and 2 (1.7° ± 0.5°, p = 0.007) for all knee flexion angles combined. No created lesion had a significant effect on medial laxity under a 10-Nm valgus torque at any degree of knee flexion. CONCLUSION: Lesions of the posterior horn of the medial meniscus are frequent in cases of anterior cruciate ligament rupture. These lesions appear to play a significant role in knee stability. Ramp lesions increase the forces in the ACL, and the PHMM is a secondary restraint to anterior tibial translation. Lesions of the meniscotibial ligament may increase rotatory instability of the knee.

The role of high tibial osteotomy in the treatment of knee laxity: a comprehensive review.

PURPOSE: The purpose of this study is to review the indications for and outcomes of high tibial osteotomy in the treatment of patients with chronic knee laxity. METHODS: A comprehensive literature review was performed to identify surgical indications and results of high tibial osteotomy for the treatment of chronic knee laxity. RESULTS: Four distinct situations were identified in which a high tibial osteotomy may be advantageous: (1) anterior laxity with varus osteoarthritis, (2) chronic anterior laxity in the setting of varus with lateral ligamentous laxity, (3) chronic anterior laxity in the setting of a high tibial slope, and (4) chronic posterior laxity or posterolateral corner injury. A total of 24 studies were included in this report, including reports of the treatment of 410 knees as well as several review articles. The most frequently reported indication for that addition of HTO was anterior laxity in the setting of varus OA, which was noted to have good results, minimizing anterior knee laxity and allowing return to sports, while reducing the progression of osteoarthritis. More advanced cases in which lateral structures have also become stretched and incompetent are an excellent indication for HTO, with the need for subsequent lateral procedures dependent on the degree of varus laxity and especially hyperextension that is present. Excessive tibial slope has been identified as a cause of ACL reconstruction failure, and some authors have recommended addressing very high slope in revision cases. In knees with chronic posterior or posterolateral instability, correction of alignment first is generally recommended, with subsequent ligamentous procedures performed when instability persists. CONCLUSIONS: Knees with chronic instability pose a difficult treatment challenge. In all cases, the contribution of coronal plane alignment to varus-valgus knee stability must be carefully considered and addressed prior to ligament surgery. Sagittal plane alignment is also key and must not be overlooked. Such considerations drive the indication for osteotomy as well as the type of osteotomy that is chosen. Level of evidence IV.

Gait changes of the ACL-deficient knee 3D kinematic assessment.

PURPOSE: Static, one-dimensional testing cannot predict the behaviour of the anterior cruciate ligament (ACL)-deficient knee under realistic loading conditions. Currently, the most widely accepted method for assessing joint movement patterns is gait analysis. The purpose of the study was in vivo evaluation of the behaviour of the anterior cruciate ligament-deficient (ACLD) knees during walking, using 3D, real-time assessment tool. METHODS: Biomechanical data were collected prospectively on 30 patients with ACL rupture and 15 healthy subjects as a control group, with KneeKg™ System. Kinematic data were recorded in vivo during treadmill walking at self-selected speed. Flexion/extension, abduction/adduction, anterior/posterior tibial translation and external/internal tibial rotation were compared between groups. RESULTS: The ACLD patients showed a significant lower extension of the knee joint during stance phase (p < 0.05; 13.2° ± 2.1° and 7.3° ± 2.7°, for ACLD and control group, respectively). A significant difference in tibial rotation angle was found in ACLD knees compared to control knees (p < 0.05). The patients with ACLD rotated the tibia more internally (-1.4° ± 0.2°) during the mid-stance phase, than control group (0.2° ± 0.3°). There was no significant difference in anteroposterior translation and adduction-abduction angles. CONCLUSION: Significant alterations of joint kinematics in the ACLD knee were revealed in this study by manifesting a higher flexion gait strategy and excessive internal tibial rotation during walking that could result in a more rapid cartilage thinning throughout the knee. The preoperative data obtained in this study will be useful to understand the post-ACL reconstruction kinematic behaviour of the knee. CLINICAL RELEVANCE: The findings in this study indicate that ACLD knee may adapt functionally to prevent excessive anterior-posterior translation but they fail to avoid rotational instability.

Lateral uni-compartmental knee replacement: current concepts and future directions.

Uni-compartmental knee replacement (UKR) is an attractive surgical option for the treatment of single compartment femoro-tibial osteoarthritis. While UKR for medial compartment arthritis is a well-established procedure with an excellent track record, UKR for lateral compartment arthritis has seen more limited success and remains a challenging operation, even in the hands of experienced arthroplasty surgeons. Despite this, several studies have now reported satisfactory mid- and long-term results with lateral UKR in appropriately selected patients. A better understanding of the aetiology and biomechanics of lateral compartment arthritis, as well as an appreciation for the technical challenges unique to lateral UKR, are likely to lead to improved outcomes with this procedure. The purpose of this level 4 study is to highlight the current concepts surrounding lateral UKR, to review the current body of literature, and to explore future directions for improving the results of lateral UKR.

Rotational laxity greater in patients with contralateral anterior cruciate ligament injury than healthy volunteers.

Rotational stability of the knee has been traditionally difficult to quantify, limiting the ability of the orthopedic community to determine the potential role of rotational laxity in the etiology of anterior cruciate ligament (ACL) injuries. The purposes of this multicenter cohort study were to evaluate the reliability of a robotic axial rotation measurement system, determine whether the uninjured knees of patients that had previous contralateral ACL reconstruction demonstrated different rotational biomechanical characteristics than a group of healthy volunteers, and determine whether knee rotational biomechanical characteristics differ between male and female non-injured limbs in groups of both healthy volunteers and patients with a previous contralateral ACL injury. Fourteen healthy volunteers and 79 patients with previous unilateral ACL injury participated in this study. Patients were tested using a computerized tibial axial rotation system. Only the normal (non-operated) knee data were used for analysis. In order to assess the reliability of the robotic measurement system, 10 healthy volunteers were tested daily over four consecutive days by four different examiners. Rotational laxity and compliance measures demonstrated excellent reliability (ICC = 0.97). Patients with a contralateral ACL injury demonstrated significantly increased tibial internal rotation (20.6° vs. 11.4°, P < 0.001) and reduced external rotation (16.7° vs. 26.6°, P < 0.001) compared to healthy volunteers. Females demonstrated significantly increased internal and external rotation, as well as significantly increased rotational compliance compared with males (P < 0.05). Computer-assisted measurement techniques may offer clinicians an accurate, reliable, non-invasive method to select the most appropriate preventative or surgical interventions for patients with increased knee rotational laxity.

Combined Patellar Tendon lengthening and partial Extensor Mechanism Allograft reconstruction for the treatment of patella infera: A case report.

Patella infera is an uncommon but potentially crippling pathology of the knee, resulting in stiffness and anterior knee pain. Several surgical methods have been described for its treatment, but there remains no clear technique of choice. We present the case of a 63-year-old male with patella infera, affecting a native knee, following Complex Regional Pain Syndrome. This patient was treated with a combined technique of Patellar Tendon lengthening and partial Hourglass Extensor Mechanism Allograft reconstruction. The results were excellent at 24 months of follow-up. To our knowledge, this technique has not yet been published, and we present it as a promising treatment option in selected cases.

[Confrontation of the radiographic preoperative planning with the postoperative data for uncemented total hip arthroplasty]. / Confrontation de la planification radiographique préopératoire et des données postopératoires lors de la mise en place des prothèses totales de hanche non cimentées.

PURPOSE OF THE STUDY: For hip prosthesis surgery, the challenge is to obtain optimal function of the instrumented hip but also to eliminate any limb length discrepancy, correct the femur offset and guarantee the center of rotation of the hip joint. Preoperative planning for total hip arthroplasty (THA) enables determination of the appropriate length for the prosthetic neck and the size and eventually the type of implants to use. From a prospective series of 86 patients who underwent first-intention THA for implantation of a noncemented prosthesis, we studied the precision of the outcome as function of the preoperative planning. We also ascertained whether the preoperative planning was sufficient to provide the measurements necessary for correct implant position. MATERIAL AND METHODS: We analyzed a prospective series of patients who underwent first-intention THA from January 2004 through January 2006. To be eligible for inclusion, patients could not have a THA of the contralateral hip. The series was composed of 58 females and 28 males, mean age 70.2 years (range 45-93). The reasons for THA were primary degenerative disease (n=76) and aseptic osteonecrosis (n=10). The contalateral hip was intact and free of osteoarthritis with an anatomic presentation considered to be normal. The standard X-ray protocol included an anteroposterior view of the pelvis in the upright position and 10 degrees internal rotation obtained preoperatively and three months postoperatively. All radiographic measurements were made by the same investigator using a manual nondigitalized technique. We compared planning parameters (pivot size and type, length of the neck, and size of the cup) with the final outcome in order to determine the compliance with the preoperative planning. All operations were performed in the lateral supine position under general anesthesia and by the same surgeon. The posterolateral Moore approach was used. All implants were press fit without cement, both for the cup and for the femoral piece. RESULTS: All planning parameters selected for study (offset, size of the head and the cup, length of the neck) were available for 32 hips, giving an overall conformity of 37%. The length of the neck was as planned in 75% of hips, the size of the cup in 62% and the size of the femoral stem in 64%. The offset defined preoperatively was never changed during the operation. Ideal implantation (+/- 5mm for all criteria selected for study) was obtained in 60% of hips; the height of the center of rotation was reproduced in 81% and the lateralization in 84%. Femur lateralization was reproduced in 75% of the hips and hip offset in 66%. Leg length discrepancy was avoided in 85% of the patients. DISCUSSION AND CONCLUSION: Preoperative planning reliably predicts the final offset of the implanted femoral stem. It is more difficult to predict the size of a press fit cup but in our experience the difference does not greatly affect restitution of the hip anatomy. We readily changed the length of the neck during the operation if necessary and have found that the leg length has been better with this approach. This leads to the observation that all of the planning parameters are not fully accurate because of the magnification effect, anatomic conditions, or possible defective execution. While the overall rate of conformity was low, looking at the results for each element separately provided a useful element for each phase of the operation. We recommend planning a medium length neck so it can be easily changed during the operation. The availability of offset measurements is particularly important to control hip lateralization and leg length. Current advances in computer-assisted surgery should be helpful in improving the imperfections of preoperative planning.

[Arthroscopy of the knee after unicompartmental arthroplasty]. / Arthroscopie après prothèse unicompartimentale du genou.

PURPOSE OF THE STUDY: Knee pain can be a problem after unicompartmental arthroplasty, compromising the long-term outcome. Arthroscopy may be useful to treat some of the causes such as cement extrusion, fibrous interposition between prosthetic elements, meniscal regeneration, hypertrophic synovitis, or arthroscopic degeneration. We evaluated the results of these procedures. MATERIAL AND METHODS: Seven patients, mean age of 75 years (range 70-79), underwent knee arthroscopy. These patients were among a series of 214 unicompartmental knee prostheses implanted from 1988 to 2005. Arthroscopy was undertaken because of persistent pain after prosthesis implantation. Repeated physical examinations, X-rays and laboratory work-ups were negative for infection or mechanical anomaly. Medical treatment was attempted. The delay before recourse to arthroscopy was 16.3 months (range 9-36 months). The series was composed of five women and two men. RESULTS: Arthroscopy after unicompartmental prosthesis enabled the discovery of chondral, meniscal, and synovial lesions which had not been diagnosed with the usual imaging and laboratory tests. Meniscal regeneration, neomeniscus, and fibrous interpositions were observed. Biopsies were obtained. The arthroscopic procedures performed were: regularization of degenerative contralateral menisci, resection of neomenisci, and synovectomy. Arthroscopic treatment by washout shaving of the cartilage lesions and regularization of the meniscal lesions provided good results. Outcome was scored excellent or good in five knees, and insufficient in two due to progressive degeneration. For one of these two knees, the non-prosthesis femorotibial compartment progressed to overt degeneration. The IKS knee score improved 13 points in the seven patients and the function score 20 points at one to five years follow-up. DISCUSSION: Arthroscopy after unicompartmental prosthesis for knee pain can give good results for unexplained pain, both in terms of diagnosis and in terms of etiological treatment. In certain knees, diagnostic arthroscopy can enable identification of the cause of pain after unicompartmental prosthesis. Therapeutic arthroscopy avoids repeated arthrotomy and shortens recovery time.

[Tibial valgus osteotomy]. / Ostéotomie tibiale de valgisation.

The tibial valgus osteotomy whatever its technique has a survival rate of about 85 % to 10 years, if we consider the reoperation as a criterion of failure, with a confidence index at 78%. The age, weight, sex and functional signs have no impact on the outcome. We have found no evidence in the preoperative radiographic assessment, neither the medial pinch, or varus epiphyseal neither varisant gap, which could be a failure and a reoperation before the tenth year. Good results were observed significantly when there is an over-valgus at least 3 degrees of global axis of the lower limb. This corresponds to a valgus epiphyseal by more than 2 degrees . The substantial reduction in the gap varisant that lowers the overall time varisant below 200 kg cm provides the same positive results. The outcome will depend directly on the accuracy of the calculation of the preoperative correction performed and the quality of surgical achievement. Because of the need for precision, navigation technique appears as reliable, simple which makes it also possible to monitor the front slope and tibial rotation induced. The osteosynthesis must be stable and rigid to avoid postoperative loss of correction.

Complications and revision surgeries in two extra-articular tenodesis techniques associated to anterior cruciate ligament reconstruction. A case-control study.

INTRODUCTION: Numerous techniques of anterior cruciate ligament (ACL) reconstruction associated to extra-articular tenodesis (EAT) have been described, but there have been few comparative studies, especially in terms of complications and revision procedures. The present study sought to compare two ACL reconstruction techniques using the patellar tendon (KJ): associating EAT by fascia lata (KJL2) or by gracilis (KJG). The study hypothesis was that the KJL2 technique incurs no extra risk of complications or surgical revision compared to the KJG technique. METHOD: A prospective case-control study compared 41 patients undergoing KJL2 and 41 controls undergoing KJG. Complications, reconstruction failure and revision procedures were assessed at a mean 13 months follow-up (range, 6-20 months). RESULTS: The KJL2 group showed no extra risk of postoperative complications or reconstruction failure compared to the KJG group: 1 versus 2 re-tears, respectively, not requiring revision. Revision surgery was significantly more frequent in the KJG group (31.7% vs. 7.3%), notably for arthrolysis and meniscectomy. DISCUSSION: The KJL2 technique is reliable, without greater risk of complications or early revision surgery than the KJG technique. LEVEL OF EVIDENCE: III - Case-control study.

Non-compliance with IDSA guidelines for patients presenting with methicillin-susceptible Staphylococcus aureus prosthetic joint infection is a risk factor for treatment failure.

OBJECTIVE: The long-term impact of treatment strategies proposed by the IDSA guidelines for patients presenting with methicillin-susceptible S. aureus (MSSA) prosthetic joint infection (PJI) is not well-known. PATIENTS AND METHODS: Retrospective (2000-2010) cohort study including patients presenting with MSSA hip or knee PJI. A univariate Cox analysis was performed to determine if the non-compliance with IDSA surgical guidelines was a risk factor for treatment failure. RESULTS: Eighty-nine patients with a mean follow-up of 2.8 years were included. Non-compliance with IDSA surgical guidelines was associated with treatment failure (hazard ratio 2.157; 95% CI [1.022-4.7]). The American Society of Anesthesiologists score, inadequate antimicrobial therapy, and a rifampicin-based regimen did not significantly influence patient outcome. CONCLUSION: Based on the IDSA guidelines, if a patient presenting with MSSA PJI is not eligible for implant retention, complete implant removal is needed to limit treatment failure.

[Surgical site infection after total knee arthroplasty: a monocenter analysis of 923 first-intention implantations]. / Infection du site opératoire après arthroplastie totale de genou.

PURPOSE OF THE STUDY: We report the results of a retrospective analysis of 923 cases of first-intention total knee arthroplasties. The objective was to determine retrospectively the rate of surgical site infections, including all infections diagnosed during the first year, and to search for risk factors. We also wanted to present our surveillance system planned for a 10-year period. MATERIAL AND METHODS: From January 1994 to January 2004, first-intention total knee arthroplasty (TKA) was performed on 999 knees. HLS prostheses were implanted. At minimum 12 months, follow-up data was complete for 923 implants which constituted the study group. Female gender predominated (72%). Mean patient was 71 years (range 26-93). Anterior surgery was performed for 25% of the knees. Etiologies were osteoarthritis (87.5%), and rheumatoid polyarthritis (6.9%). Cefazolin was used for systematic preoperative (one injection) and postoperative (48 hr) antibiotic proxphylaxis. Vancomycin was used for patients with a contraindication for cefazolin. Information was collected from two sources: computerized consultation charts for all follow-up visits completed prospectively since 1995 et data collected by the Hygiene and Epidemiology Unit during the year following implantation. Data on surgical site infections was collected from the hospitalization files, outpatient files and control visits. Each case of infection was validated at an annual interdisciplinary meeting. We retained for analysis deep infections requiring revision surgery with identification of the causal agent on the intraoperative samples. We identified a subgroup of infections occurring during the first postoperative year, the delay generally retained for surgical site infections. RESULTS: Twenty surgical site infections after TKA were identified during the 10-year surveillance period (2.1%). Mean follow-up was 43 months (range 12-123 months, median 37 months). The rate of surgical site infections occurring during the first postoperative year was 1.4%. Eighty-percent of the infections (n=16) occurred within the first two postoperative months. Two infections were diagnosed two to five years after surgery and two others more than five years after surgery due to hematogenous contamination. All of the observed infections involved a single causal germ. Agents identified were: Gram+ (90%) and Gram- (10%), with a clear predominance for Staphylococcus aureus (n=9). Infections developed 2.1-fold more often in patients with an inflammatory disease (rheumatoid polyarthritis). Age and body mass index did not differ between patients with and without surgical site infection. CONCLUSION: The analysis of our series demonstrated the difficulties in conducting long-term surveillance.