Consistent indications, targets and techniques for double-level osteotomy of the knee: a systematic review.

PURPOSE: To systematically review and critically appraise the literature on double-level osteotomy (DLO) of the knee, and determine the indications, contraindications, targets and outcomes. MATERIALS AND METHODS: A systematic literature search was performed on PubMed, Embase®, and Cochrane for studies that reported on DLO by any technique or approach, including indications, contraindications, and targets for DLO, as well as patient-reported outcome measures (pROMS) and radiographic angles. RESULTS: Twelve eligible studies were found: 9 case series and 3 studies that compared DLO to high-tibial osteotomy (HTO). In all studies, DLO was performed by medial opening-wedge tibial osteotomy and lateral closing-wedge femoral osteotomy. Seven specified that DLO was performed if simple HTO would exceed thresholds of postoperative medial proximal tibial angle (MPTA), lateral distal femoral angle (LDFA), and/or predicted wedge size. The targets were 88°-95° for MPTA, 84°-89° for LDFA, and 0°-4° for hip-knee-ankle (HKA) angle. The 3 comparative studies reported lower MPTA after DLO (89.6°-92.5°) than after HTO (91.5°-98.3°). All 3 reported similar postoperative HKA after DLO (0.2°-4.4°) as HTO (0.4°-4.8°); only 2 compared postoperative LDFA, which was lower after DLO (85.4° and 84.9°) than HTO (88.7° and 88.8°). Two comparative studies reported postoperative overall KOOS which was slightly lower after DLO (351-403) than HTO (368-410); only 1 study reported separate items of the KOOS. CONCLUSION: There was relative consistency between studies on the indications, targets and techniques for DLO. Furthermore, while the comparative studies reported similar preoperative MPTA, LDFA and HKA, the postoperative MPTA and LDFA were lower after DLO than after HTO, though both treatments achieved equivalent postoperative HKA. LEVEL OF EVIDENCE: IV, systematic review.

History of previous surgery is associated with higher risk of revision after primary total knee arthroplasty: a cohort study from the Geneva Arthroplasty Registry.

Background and purpose - Prior to primary total knee arthroplasty (pTKA), 6-34% of patients have undergone surgical procedure(s) of their knee. We investigated whether history of previous surgeries influences the risk of revision of pTKA, the risk according to the type of previous surgery, and how previous surgery influences specific causes of revision and the time of revision.Patients and methods - This is a prospective cohort study from the Geneva Arthroplasty Registry. All pTKA between 2000 and 2016 were included and followed until December 31, 2019. Outcomes were risk of revision, evaluated using Kaplan-Meier survival and Cox and competing risks regression, the specific causes, and time of revision.Results - Of 3,945 pTKA included (mean age 71 years, 68% women), 21% had a history of previous surgery, with 8.3% revisions vs. 4.3%, at 3-20 years' follow-up (mean 8.6). 5- and 10-year cumulative failure by previous surgery (yes vs. no) were 6.6% (95% CI 5.1-8.5) vs. 3.3% (CI 2.7-4.0), and 8.4% (CI 6.6-10.6) vs. 4.5% (CI 3.8-5.4). Baseline differences explained only part of the higher risk (adjusted HR 1.5, CI 1.1-2.1). The risk of failure was higher for all causes of revision considered. Patients in the previous surgery group had a higher risk of an early revision.Interpretation - A history of previous surgery adversely affected the outcome with a 1.5 times higher cumulative risk of all-cause revision over the course of up to 20 years after index surgery. The increased risk was seen for all causes of revision and was highest in the first years.

[Lessons learned from 25 years of an institutional hip and knee arthroplasty registry]. / Leçons apprises par 25 ans d'un registre institutionnel des prothèses de hanche et de genou.

Since 1996, the Geneva Arthroplasty Registry at the University Hospitals of Geneva (HUG) has been collecting, archiving and disseminating relevant high-quality information on primary total hip and knee arthroplasties and revision procedures performed at the Division of Orthopaedics and Traumatology. Patients are followed throughout their lifetime with the prosthesis. The registry has been essential to better understand and subsequently improve the care of patients with hip and knee replacements. It will continue to fulfil its mission and to work towards an even more effective transfer of the knowledge obtained to all stakeholders and as well as towards its implementation.

Depuis 1996, le registre genevois des arthroplasties aux HUG recueille, archive et diffuse des informations pertinentes de haute qualité concernant les arthroplasties primaires de la hanche et du genou ainsi que les procédures de révision réalisées au Service de chirurgie orthopédique et traumatologie de l'appareil moteur. Les patients sont suivis pendant toute leur vie avec la prothèse. Le registre a été essentiel pour mieux comprendre et ensuite améliorer la prise en charge de patients avec arthroplastie de hanche et de genou. Il continuera à remplir sa mission et à assurer une transmission encore plus efficace des connaissances obtenues vers tous les groupes concernés (stakeholders) et à leur implémentation.

Walking Speed and Maximal Knee Flexion During Gait After Total Knee Arthroplasty: Minimal Clinically Important Improvement Is Not Determinable; Patient Acceptable Symptom State Is Potentially Useful.

BACKGROUND: Total knee arthroplasty (TKA) is the operation of choice in patients with end-stage knee osteoarthritis (OA). Up to 1 in 5 patients still encounter functional limitations after TKA, partly explaining patient dissatisfaction. Which gait ability to target after TKA remains unclear. To determine whether Minimal Clinical Important Improvement (MCII) or Patient Acceptable Symptom State (PASS) values could be derived from gait parameters recorded in patients with TKA. And, if so, to define those values. METHODS: In this ancillary study, we retrospectively analyzed gait parameters of patients scheduled for a unilateral TKA between 2011 and 2013. We investigated MCII and PASS values for walking speed and maximal knee flexion using anchor-based methods: 5 anchoring questions based on perceived body function and patients' satisfaction. RESULTS: Over the study period, 79 patients performed a clinical gait analysis the week before and 1 year after surgery, and were included in the present study. All clinical and gait parameters improved 1 year after TKA. Nevertheless, changes in gait outcomes were not associated with perceived body function or patients' satisfaction, precluding any MCII estimation in gait parameters. PASS values, however, could be determined as 1.2 m/s for walking speed and 50° for maximal knee flexion. CONCLUSION: In this study, we found that MCII and PASS values are not necessarily determinable for gait parameters after TKA in patients with end-stage OA. Using anchor questions based on perceived body function and patient's satisfaction, MCII could not be defined while PASS values were potentially useful. LEVEL OF EVIDENCE: Level III.

[Robotic surgery : the future of prosthetic surgery ?] / Chirurgie robotique : l'avenir de la chirurgie prothétique ?

Indications for hip and knee replacement will continue to grow over the next few years. Robotic systems have been developed since the early 1990s in order to optimize implant positioning, to potentially improve clinical results, and to reduce perioperative morbidity. Currently, the different available systems certainly improve the accuracy and reproducibility of prosthetic components placement. However, the cost of robotic surgery remains very high. Early results in terms of implant survival, postoperative pain, mobility, and length of stay are encouraging. Long-term studies are needed to validate the clinical efficacy and to perform a medico-economic evaluation of robots in orthopedic surgery.

Les indications de mise en place des prothèses de hanche et de genou ne cesseront de croître au cours des prochaines années. Afin de parfaire la technique d'implantation, d'améliorer les résultats cliniques et de réduire la morbidité périopératoire, l'emploi de systèmes robotiques fait l'objet d'un intérêt grandissant depuis le début des années 90. Actuellement, les différents systèmes disponibles permettent assurément d'améliorer la reproductibilité et la précision de l'implantation des prothèses aux dépens de coûts encore élevés. Les résultats précoces en termes de survie des implants, de douleur et de mobilité post-opératoires sont encourageants. Des études au long terme seront nécessaires afin de confirmer ces derniers et valider l'efficacité clinique ainsi que l'intérêt médico-économique des robots en chirurgie orthopédique.

Important patient characteristics differ prior to total knee arthroplasty and total hip arthroplasty between Switzerland and the United States.

BACKGROUND: Outcomes after total knee (TKA) and hip (THA) arthroplasty are often generalized internationally. Patient-dependent factors and preoperative symptom levels may differ across countries. We compared preoperative patient and clinical characteristics from two large cohorts, one in Switzerland, the other in the US. METHODS: Patient characteristics were collected prospectively on all elective primary TKAs and THAs performed at a large Swiss hospital and in a US national sample. Data included age, sex, education level, BMI, diagnosis, medical co-morbidities, PROMs (WOMAC pain/function), global health (SF-12). RESULTS: Six thousand six hundred eighty primary TKAs (US) and 823 TKAs (Swiss) were evaluated. US vs. Switzerland TKA patients were younger (mean age 67 vs. 72 years.), more obese (BMI ≥30 55% vs. 43%), had higher levels of education, more cardiac disease. Swiss patients had lower preoperative WOMAC pain scores (41 vs. 52) but pre-operative physical disability were comparable. 4,647 primary THAs (US) and 1,023 THAs (Swiss) were evaluated. US vs. Switzerland patients were younger (65 vs. 68 years.), more obese (BMI ≥30: 38% vs. 24%), had higher levels of education, more diabetes. Swiss patients had lower preoperative WOMAC pain scores (40 vs. 48 points). Physical disability was reported comparable, but Swiss patients indicated lower mental health scores. CONCLUSION: We found substantial differences between US and Swiss cohorts in pre-operative patient characteristics and pain levels, which has potentially important implications for cross-cultural comparison of TKA/THA outcomes. Reports from national registries lack detailed patient information while these data suggest the need for adequate risk adjustment of patient factors.

Knee Kinematic and Clinical Outcomes Evolution Before, 3 Months, and 1 Year After Total Knee Arthroplasty.

BACKGROUND: The aim of this study was to describe the evolution of kinematic and clinical outcomes of a large patient cohort with knee osteoarthritis from before surgery (V1) to 3 months (V2) and 1 year (V3) after a total knee arthroplasty (TKA). METHODS: The patients were evaluated at each visit (118 patients at V1, 93 patients at V2, and 79 patients at V3) during a clinical gait analysis and were compared with a matched control group of healthy adults (CG). The kinematic parameters, the Western Ontario and MacMaster Osteoarthritis Index (WOMAC), quality of life, and patient satisfaction were assessed. Gait velocity and knee range of motion (ROM) as well as clinical parameters were compared at each visit with CG was based on the unpaired samples t-test. To determine changes in the data at baseline, 3 months, and 1 year after surgery in the patient groups, repeated-measure analysis of variance was conducted (P < .05). Pearson correlation was used to examine relationships between clinical and biomechanical outcomes. RESULTS: One year after TKA (V3) compared to V1 and V2, the ROM of the operated knee during gait was significantly improved (V1: 44.2 ± 8.8° vs V3: 47.5 ± 7.1°, P < .001, and V2: 42.2 ± 9.3° vs V3: 47.5 ± 7.1°, P = .001), as was the gait velocity (V1: 1.0 ± 0.2 and V2: 1.1 ± 0.2 m/s vs V3: 1.3 ± 0.2 m/s, P < .001). The WOMAC and knee pain were significantly better 1 year after TKA. No strong relationships have been found between clinical parameters and knee kinematics. CONCLUSION: This study showed that 1 year after TKA, patients exhibited improved gait velocity and ROM and experienced a significant decrease in the level of pain and an increased clinical score (although different from CG).

Influence of Body Mass Index on Sagittal Knee Range of Motion and Gait Speed Recovery 1-Year After Total Knee Arthroplasty.

BACKGROUND: The purpose of this prospective study was to investigate the influence of body mass index (BMI) on gait parameters preoperatively and 1 year after total knee arthroplasty (TKA). METHODS: Seventy-nine patients were evaluated before and 1 year after TKA using clinical gait analysis. The gait velocity, the knee range of motion (ROM) during gait, their gains (difference between baseline and 1 year after TKA), the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), quality of life, and patient satisfaction were assessed. Nonobese (BMI <30 kg/m2) and obese patients (BMI ≥30 kg/m2) were compared. Healthy controls were also assessed. Univariate and multivariate linear regression analyses were used to assess the association between gait speed and ROM gains. Adjustment was performed for gender, age, and WOMAC pain improvement. RESULTS: At baseline, gait velocity and knee ROM were significantly lower in obese compared with those in the nonobese patients (0.99 ± 0.27 m/s vs 1.11 ± 0.18 m/s; effect size, 0.53; P = .021; and ROM, 41.33° ± 9.6° vs 46.05° ± 8.39°; effect size, 0.52; P = .022). Univariate and multivariate linear regressions did not show any significant relation between gait speed gain or knee ROM gain and BMI. At baseline, obese patients were more symptomatic than nonobese (WOMAC pain: 36.1 ± 14.0 vs 50.4 ± 16.9; effect size, 0.9; P < .001), and their improvement was significantly higher (WOMAC pain gain, 44.5 vs 32.3; effect size, 0.59; P = .011). CONCLUSION: These findings show that all patients improved biomechanically and clinically, regardless of their BMI.

[Does total knee arthroplasty meet patient's expectations ?] / La prothèse totale du genou répond-elle aux attentes des patients ?

Total knee arthroplasty has grown considerably over the past decade, due to the aging of the population, the increase in the prevalence of obesity, and an increasing demand. The 10-year revision rate is less than 5%. Functional outcomes, assessed by range of motion measures and functional scores, were significantly improved with the advent of more reliable and less invasive surgical techniques, better management of postoperative pain, and early high-intensity rehabilitation protocols. However, 20% of patients say they are dissatisfied with their knee replacement, either because of the persistence of pain, or because their function does not match their preoperative expectations. Improved preoperative communication between patient and surgeon is essential to match patients' expectations to realistic treatment outcomes.

L'arthroplastie du genou connaît un essor considérable en raison du vieillissement de la population, de l'augmentation de la prévalence de l'obésité et de l'augmentation de la demande. Le taux de reprise à 10 ans est inférieur à 5 %. Les résultats fonctionnels ont été incontestablement améliorés grâce à des techniques chirurgicales plus fiables et moins invasives, à une meilleure gestion de la douleur postopératoire, et à l'instauration d'une physiothérapie intense et précoce. Cependant, 20 % des patients se disent insatisfaits après prothèse totale du genou, soit en raison de la persistance de douleurs, soit en raison d'une fonction qui ne correspond pas à leurs attentes. L'adéquation des attentes, évaluées lors de la consultation préopératoire, avec un niveau de performance réaliste apparaît comme un gage de satisfaction postopératoire.

[Do degenerative meniscal tears need surgery ?] / Faut-il opérer les lésions dégénératives du ménisque ?

Degenerative meniscal tears (DMT) are common, often asymptomatic, and are associated with early-stage knee osteoarthritis in patients over 35 years of age. Conservative treatment, including exercise, physiotherapy and pain medication, should be offered as a first management approach for patients with symptomatic DMT. The indication for partial arthroscopic meniscectomy should be considered carefully, and based on specific criteria. Recently, several randomized controlled studies comparing partial medial meniscectomy to conservative treatment or to a sham procedure have questioned the effectiveness of surgical treatment of these lesions.The purpose of this article is to provide an update on the diagnosis and treatment of DMT.

Les lésions méniscales dégénératives (LMD) sont fréquentes, souvent asymptomatiques et considérées comme une préarthrose chez le patient de plus de 35 ans. Lorsqu'elles sont associées à une douleur du genou, le traitement conservateur est le premier choix. En cas d'échec, l'indication à une méniscectomie partielle par arthroscopie doit être réfléchie et repose sur des critères précis. Récemment, plusieurs études randomisées ont remis en cause l'efficacité du traitement chirurgical de ces lésions. Celui-ci n'apporterait pas de bénéfice par rapport au traitement médical ou à une chirurgie « placebo ¼. Le but de cet article est de faire le point sur le diagnostic et la prise en charge des LMD.

Influence of body mass index on revision rates after primary total knee arthroplasty.

PURPOSE: Studies demonstrate that revision rates after primary total knee arthroplasty (TKA) tend to be higher in obese patients. However, the existence of a body mass index (BMI) threshold remains unexplored. METHODS: We conducted a prospective cohort study of 2442 primary TKAs in 2035 patients (69.1 % women; mean age 72 years; mean follow-up 93 months, range 38-203). We evaluated the influence of BMI in five categories on all-cause revision after TKA using incidence rates (IR), hazard ratios (HR), and Kaplan-Meier survival analysis. Adjustment for baseline imbalances was performed using Cox regression analysis. RESULTS: Over the study period, 71 revisions occurred. Revision rates were 3.2 cases/1000 patient-years for patients of normal weight, 3.4/1000 for overweight patients and 3.0/1000 for patients classified as obese class I. At BMI ≥ 35, a significant increase in revision was noted. Comparing BMI ≥ 35 vs. < 35, there were 6.4 vs. 3.2 /1000. Crude HR was 2.0 [95 % confidence interval (CI) 1.2-3.3, p = 0.009], and the adjusted HR was 2.1 (95 % CI 1.2-3.6, p = 0.008). CONCLUSION: All-cause revision rates after primary TKA doubled in patients with a BMI of 35 but were similar in those with a BMI <35.

Body mass and weight thresholds for increased prosthetic joint infection rates after primary total joint arthroplasty.

BACKGROUND AND PURPOSE: Obesity increases the risk of deep infection after total joint arthroplasty (TJA). Our objective was to determine whether there may be body mass index (BMI) and weight thresholds indicating a higher prosthetic joint infection rate. PATIENTS AND METHODS: We included all 9,061 primary hip and knee arthroplasties (mean age 70 years, 61% women) performed between March 1996 and December 2013 where the patient had received intravenous cefuroxime (1.5 g) perioperatively. The main exposures of interest were BMI (5 categories: < 24.9, 25-29.9, 30-34.9, 35-39.9, and ≥ 40) and weight (5 categories: < 60, 60-79, 80-99, 100-119, and ≥ 120 kg). Numbers of TJAs according to BMI categories (lowest to highest) were as follows: 2,956, 3,350, 1,908, 633, and 214, respectively. The main outcome was prosthetic joint infection. The mean follow-up time was 6.5 years (0.5-18 years). RESULTS: 111 prosthetic joint infections were observed: 68 postoperative, 16 hematogenous, and 27 of undetermined cause. Incidence rates were similar in the first 3 BMI categories (< 35), but they were twice as high with BMI 35-39.9 (adjusted HR = 2.1, 95% CI: 1.1-4.3) and 4 times higher with BMI ≥ 40 (adjusted HR = 4.2, 95% CI: 1.8-9.7). Weight ≥ 100 kg was identified as threshold for a significant increase in infection from the early postoperative period onward (adjusted HR = 2.1, 95% CI: 1.3-3.6). INTERPRETATION: BMI ≥ 35 or weight ≥ 100 kg may serve as a cutoff for higher perioperative dosage of antibiotics.

No regeneration of the human acetabular labrum after excision to bone.

BACKGROUND: Treatment options for a symptomatic, torn, irreparable, or completely ossified acetabular labrum are limited to either excision and/or reconstruction with grafts. In a previous animal model, regeneration of the acetabular labrum after excision to the bony rim has been shown. In humans, less is known about the potential of regeneration of the labrum. Recent studies seem to confirm labral regrowth, but it is still unclear if wide excision might be a surgical option in cases where repair is not possible. QUESTIONS/PURPOSES: The purposes of this study were (1) to determine the extent of acetabular labrum regeneration after excision to the bony rim; and (2) to determine whether this procedure results in higher hip scores. METHODS: We reviewed all patients treated with surgical dislocation for symptomatic femoroacetabular impingement by a single surgeon at one institution between 2003 and 2008, of whom 14 underwent wide labral excision (of at least 60°) down to bone; we used this approach when there was an absence of reparable tissue. Of these 14, nine were available for voluntary reexamination. The mean age at surgery was 38 ± 9 SD years and the mean followup was 4 ± 1 SD years. All patients consented to a physical examination and an MRI arthrogram, which was evaluated for evidence of new tissue formation by four observers. A modified Harris hip score and the UCLA were recorded. RESULTS: Regrowth of a structure equivalent to normal labrum was not observed on the MRI arthrograms. Six of nine hips had segmental defects, bone formation was found in five, and the capsule was confluent with the new tissue in six. The mean Harris hip score at latest followup was 83 ± 14, and the mean UCLA score was 6 ± 2. CONCLUSIONS: Resection of a nonreparable acetabular labrum down to a bleeding bony surface does not stimulate regrowth of tissue that appears to be capable of normal function by MR arthrography, and patients who underwent this procedure had lower hip scores at midterm than previously reported from the same institution for patients undergoing labral repair or sparse débridement. Based on these results, we believe that future studies should evaluate alternatives to reconstructing the labrum, perhaps using ligamentum teres, because resection seems neither to result in regrowth nor the restoration of consistently high hip scores.

Primary open anterior shoulder stabilization: a long-term, retrospective cohort study on the impact of subscapularis muscle alterations on recurrence.

BACKGROUND: Post-traumatic anterior shoulder instability patients may present histopathologic lesions within the subscapularis muscle compatible with a scarring process associated with disuse atrophy. We hypothesized that such lesions identified on intraoperative biopsy at the time of primary anterior shoulder stabilization would predict a higher risk of postoperative instability recurrence. METHODS: Of 52 eligible patients (52 shoulders) who had undergone subscapularis muscle biopsy during primary anterior open labral repair and capsulorrhaphy, 35 (mean age at surgery, 27.2 years; male sex, 71.4%) were retrospectively evaluated (mean follow-up, 12.9 years; range, 10.9-14.5 years). Primary outcome was shoulder instability recurrence. Secondary outcomes included shoulder range of motion, functional scores, and radiological analysis of glenohumeral joint degenerative changes. RESULTS: Overall five patients (14.3%) presented shoulder instability recurrence. Twelve patients with histopathologic lesions had significantly more instability recurrence than 23 without histopathologic changes (33.3% vs. 4.3%; risk difference, 29% [95% CI 1; 57]; p = 0.038). Patients without histopathologic changes had significantly reduced external rotation with arm at side (ER1; -11.9°; p = 0.001) and with shoulder abducted to 90° (ER2; -14.9°; p = 0.001) on the operated side when compared to the contralateral side. Patients with histopathologic lesions had only ER2 significantly reduced (-8.9°; p = 0.031). There was no substantial difference regarding functional and quantitative radiological scores between both patients' groups. CONCLUSIONS: Histopathologic changes within the subscapularis muscle at the time of primary open labral repair and capsulorrhaphy were associated with an increased risk of shoulder instability recurrence. Further investigations are needed to assess the impact of dedicated postoperative rehabilitation programs for patients presenting these lesions. Their recognition on preoperative magnetic resonance imaging should also be investigated; non-anatomical repairs could be an option in these cases.

[Management of malignant bone tumors around the knee]. / Prise en charge des tumeurs osseuses malignes autour du genou.

Primary bone tumors arise mostly around the knee. A treatment strategy issued from a multidisciplinary team is the key factor for an optimal management of such patients. Many durable options for reconstructing a functional limb are available, as an alternative to amputation, without lowering patients' survival. Nevertheless complications are frequent and any decision for one technique or the other should be made with the patient, appreciating the specificity of each single case. We discuss here the different techniques with their advantages and drawbacks, including long term results.

[Unicompartmental knee replacement]. / Prothèses unicompartimentales du genou.

Unicompartmental knee arthroplasties (UKA) have been created to treat primary unicompartmental knee arthritis. They are indicated in case of lower-limb deformity due to unicompartmental arthritis, but not to treat unicompartmental arthritis due to extra-articular deformity. Early failures are do to ligamentar problems or to surgical technical errors. Late failures as wear or loosening are undoubtely delayed by adequate surgical indication and technique. Indeed the 10 years PUC survival is 90%. Patient age is not a selection criteria because both young (50-60 years old) and old (> 80 years old) patients may benefit of a UKA. UKA allows a young patient to continue low-impact sports and octagenarians will benefit of the lower morbidity of UKA surgery.

Comparison between passive knee kinematics during surgery and active knee kinematics during walking: A preliminary study.

Recovery of function is among a patient's main expectations when undergoing total knee arthroplasty (TKA). However, normal gait knee function is not always completely restored, which can affect patient satisfaction and quality of life. Computer-assisted surgery (CAS) allows surgeons to evaluate passive knee kinematics intra-operatively. Understanding associations between knee kinematics measured during surgery and during daily activities, such as walking, could help define criteria for success based on knee function and not only on the correct alignment of the implant or the leg. This preliminary study compared passive knee kinematics measured during surgery with active kinematics measured during walking. Eight patients underwent a treadmill gait analysis using the KneeKG™ system both before surgery and three months afterwards. Knee kinematics were measured during CAS both before and after TKA implantation. The anatomical axes of the KneeKG™ and CAS systems were homogenised using a two-level, multi-body kinematics optimisation with a kinematic chain based on the calibration measured during CAS. A Bland-Altman analysis was performed before and after TKA for adduction-abduction angle, internal-external rotation, and anterior-posterior displacement over the whole gait cycle, at the single stance phase and at the swing phase. Homogenising the anatomical axes between CAS and treadmill gait led to limited median bias and limits of agreement (post-surgery -0.6 ± 3.6 deg, -2.7 ± 3.6 deg, and -0.2 ± 2.4 mm for adduction-abduction, internal-external rotation and anterior-posterior displacement, respectively). At the individual level, correlations between the two systems were mostly weak (R2 < 0.3) over the whole gait cycle, indicating low kinematic consistency between the two measurements. However, correlations were better at the phase level, especially the swing phase. The multiple sources of differences did not enable us to conclude whether they came from anatomical and biomechanical differences or from measurement system errors.

Clinical and objective gait outcomes remained stable seven years after total knee arthroplasty: A prospective longitudinal study of 28 patients.

BACKGROUND: There is a paucity of data on mid to long-term gait outcomes after total knee arthroplasty. The aims of this longitudinal study were: to assess the evolution of both clinical and gait outcomes before and up to seven years after primary total knee arthroplasty (TKA) in a cohort of patients with knee osteoarthritis. METHODS: This study included 28 patients evaluated before and up to seven years after primary TKA with both gait analysis and patient reported outcomes; of these, 20 patients were evaluated one year after surgery as well. Kinematic outcomes during gait (gait velocity, dimensionless gait veolicity, maximal knee flexion and knee range of motion), pain relief, Western Ontario and MacMaster Osteoarthritis Index (WOMAC), quality of life and patient satisfaction were assessed and compared at each visit with the paired Wilcoxon signed rank test (p < 0.05). RESULTS: The significant improvement achieved at one year after TKA was stable up to seven years after surgery, with all clinical and kinematic outcomes unchanged, except for gait velocity, with a significant decrease over time (1.3 (1.1-1.4) m/s one year after TKA versus 1.0 (0.9-1.1) m/s, p < 0.05 up to seven years after). CONCLUSION: Patients with knee osteoarthritis significantly improve their clinical and kinematic outcomes at one year postoperatively and maintain the gain up to seven years after primary TKA, except for gait velocity which decreases over time, most likely along with ageing.

The German Hip Outcome Score: validation in patients undergoing surgical treatment for femoroacetabular impingement.

PURPOSE: To cross-culturally adapt and validate the Hip Outcome Score (HOS) for use in German-speaking patients undergoing surgical treatment for femoroacetabular impingement. METHODS: After cross-cultural adaptation (German-language version of the HOS [HOS-D]), the following metric properties of the questionnaire were assessed in 85 consecutive patients (mean age, 33.4 years; 36 women) undergoing hip arthroscopy or surgical hip dislocation: feasibility, reliability, internal consistency, and construct validity (correlation with Western Ontario and McMaster Universities Arthritis Index, Oxford Hip Score, Short Form 12, and University of California, Los Angeles activity scale). We calculated floor and ceiling effects taking the minimal detectable change into account. RESULTS: The activities of daily living subscale of the HOS-D could be scored in all cases and the sport subscale in all but one. The HOS-D scores were highly reproducible with intraclass correlation coefficients of 0.94 for the activities of daily living subscale and 0.89 for the sport subscale. Internal consistency was confirmed by Cronbach α values >0.90 for both subscales. Correlation coefficients with the other measures ranged from -0.08 (Mental Component Scale of Short Form 12) to -0.90 (Western Ontario and McMaster Universities Arthritis Index function subscale). CONCLUSIONS: The HOS-D is a reliable and valid self-assessment tool for patients undergoing surgical femoroacetabular impingement treatment. By use of the HOS, comparisons between studies and treatment regimens involving either German- or English-speaking patients are now possible. LEVEL OF EVIDENCE: Level I, testing of previously developed diagnostic criteria in a series of consecutive patients with universally applied gold standard.