[Interpretation of systematic review articles and meta-analyses : Clinical trials in trauma surgery and orthopedics]. / Interpretation von systematischen Übersichtsarbeiten und Metaanalysen : Klinische Studien in Unfallchirurgie und Orthopädie.

Clinical trials must be planned and interpreted in the context of current best clinical and scientific evidence, undoubtedly provided by systematic reviews and meta-analyses, especially Cochrane Reviews. While many clinicians feel overwhelmed by this complex data source, few visualElements (e.g., the traffic light system of the Cochrane risk of bias [RoB­2] tool, forest plots, etc.), together with indices such as the I2 heterogeneity statistic, allow for a quick appraisal of all critical and necessary qualitative and quantitative information. The effectiveness of different treatment options can indirectly be assessed by methodological advancements like network meta-analyses.Point estimates of percentages are insufficient to describe the utility and value of a proposed novel intervention, which, in orthopedic and trauma surgery, often represents a step innovation. 95% confidence intervals and the so-called fragility index are helpful in determining the ultimate patient benefit.

Intraoperative analysis of patellofemoral joint morphology before and after total knee arthroplasty : A feasibility study.

BACKGROUND: Patellofemoral problems after total knee arthroplast (TKA) are frequent and often associated with a change in the geometry of the trochlear groove. OBJECTIVE: The present study aimed to analyze the feasibility of intraoperative examination of the patellofemoral joint geometry before and after the implantation of bicondylar total knee replacements without exposing the patient to radiation. MATERIAL AND METHODS: The patellofemoral joint morphology geometries of 33 patients before and after implantation of a bicondylar total knee replacement was intraoperatively analyzed using a digital scanning method. Femoral surface geometries were extracted from intraoperatively recorded tactile scanning data using an in-house algorithm. The geometries were then characterized by sulcus height, medial femoral condyle height and lateral femoral condyle height. RESULTS: Our preliminary results show that these key geometric parameters are only partially restored after TKA leading to a distinctly different shaped profile of the anterior distal femur. Maximum and minimum mean differences in sulcus height, medial femoral condyle height, and lateral femoral condyle height before and after surgery were 2.00 mm/-3.06 mm, 2.51 mm/-6.25 mm and 2.74 mm/-3.58 mm, respectively. CONCLUSION: A new method for intraoperative analysis of the patellofemoral joint morphology before and after TKA without radiation exposure was developed and utilized. Even with the use of modern total knee designs, the patellofemoral articulation is considerably changed postoperatively as quantified by the key parameters of sulcus height, medial femoral condyle height, and lateral femoral condyle height. This may result in altered knee biomechanics and might explain persistent patellofemoral disorders, which are often reported by patients after TKA.

The impact of illness perception on functionality, pain, stiffness, and activity of daily living after total hip replacement surgery.

OBJECTIVE: According to the Common Sense Model (CSM), cognitive and emotional representations influence recovery. We used groups of individuals grouping multiple cognitive representations (schemas) to predict the recovery process after total hip arthroplasty (THR). METHODS: The aim of this prospective cohort study with three collection time points was to examine the significance of these schemas for functionality three and six months after THR. We assessed illness perception with the Illness Perception Questionnaire-Revised and the functionality with the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Data were collected four weeks before (n = 317), three (n = 268), and six months after (n = 292) primary THR. Groups of individuals with the same schemas were identified using a two-step cluster analysis across cognitive representations. Controlling for WOMAC variables (functionality, stiffness, pain, and activities of daily living) before THR, we calculated the regression of schemas and emotional representations before THR on WOMAC variables after THR. RESULTS: Before THR, two cognitive schemes were found: Schema One: medium identity, long duration, many consequences, low personal and treatment control, and low coherence; Schema Two: low identity, short timeline, low consequences, and high personal and treatment control. Patients with Schema Two had better functionality and lower pain and stiffness three months after surgery compared to those with Schema One. After three months, the influence of cognitive schemas was stronger on functionality than that of emotional representation (f2: 0.04 /0.02). CONCLUSION: Further study is needed to determine whether a psychological intervention can change Schema One.

[Clinical studies in trauma surgery and orthopedics: read, interpret and implement]. / Klinische Studien in Unfallchirurgie und Orthopädie: lesen, interpretieren und umsetzen.

Informative, participatory clinical decision-making needs to combine both skills and expertise as well as current scientific evidence. The flood of digital information makes it difficult in everyday clinical practice to keep up to date with the latest publications. This article provides assistance for coping with this problem. A basic understanding of prior and posterior probabilities as well as systematic error (bias) makes it easier to weigh up the benefits and risks, e.g. of a (surgical) intervention compared to a nonsurgical treatment. Randomized controlled trials (RCT, with all modern modifications) deliver undistorted results but in orthopedic and trauma surgery can lead to a heavily selected nonrepresentative sample and the results must be confirmed or refuted by further, independent RCTs. Large-scale observational data (e.g. from registries) can be modelled in a quasi-experimental manner and accompany RCTs in health technology assessment.

Similar outcomes in computer-assisted and conventional total knee arthroplasty: ten-year results of a prospective randomized study.

BACKGROUND: Computer-assisted navigation (CAS) was developed to improve the surgical accuracy and precision. Many studies demonstrated better alignment in the coronal plane in CAS TKA compared to conventional technique. The influence on the functional outcome is still unclear. Only few studies report long-term results of CAS TKA. This study was initiated to investigate 10-year patient-reported outcome of CAS and conventional TKA. METHODS: From initially 80 patients of a randomized study of CAS and conventional TKA a total of 50 patients could be evaluated at the 10-year follow-up. The Knee Society Score and EuroQuol Questionnaire were assessed. For all patients a competing risk analysis for revision was performed. RESULTS: The patient-reported outcome measures demonstrated similar values for both groups. The 10-year risk for revision was 2.5% for conventional TKA and 7.5% for CAS TKA (p=0.237). CONCLUSIONS: There was no difference between CAS and conventional TKA with regard to patient-reported outcome and revision risk ten years after surgery. TRIAL REGISTRATION: This study was registered at clinicaltrials.gov on 11/30/2009, ID: NCT01022099 .

Fulfillment of expectations influence patient satisfaction 5 years after total knee arthroplasty.

PURPOSE: Constant efforts have been made to improve prosthesis design in total knee arthroplasty (TKA), but a significant number of patients remain dissatisfied postoperatively. Besides poor improvement in pain or function, poor fulfillment of patients expectations were identified as contributing factors. Purpose of the study was to assess fulfillment of patients' expectations and satisfaction with TKA 5 years after surgery. METHODS: A total of 103 patients from a prospective randomised study of a high-flexion or standard TKA implant were investigated 5 years after surgery and patient-reported outcomes (PRO), fulfillment of expectations and satisfaction with the result of the surgery were obtained. RESULTS: There were no differences in PROs, fulfillment of expectations and satisfaction between both implant designs. In total, the patients had high expectations preoperatively, mainly related to pain relief and functional abilities. A total of 89.4% of these expectations were fulfilled. No re-interventions (p < 0.001) and male gender (p = 0.017) were the most important predictors of higher fulfillment of expectations. Satisfaction scored highly at 8.2 out of 10 and most patients (93.2%) would undergo the surgery again. Higher Knee Score (p = 0.012) and fulfillment of expectations (p = 0.002) were correlated with higher satisfaction. CONCLUSION: Five years after surgery fulfillment of expectations and satisfaction were high regardless of implant design and did significantly influence patient satisfaction. Surgeons should be aware of the importance of patients' expectations and their influence on satisfaction after TKA. Therefore, the probability of fulfillment should be discussed during shared decision making for TKA. LEVEL OF EVIDENCE: I.

Microarray analysis for delineating the gene expression in biopsies of gastrocnemius muscle of patients with chronic critical limb ischaemia compared with non-ischaemic controls.

BACKGROUND: Microarray analysis has been carried out in this pilot study to compare delineated gene expression profiles in the biopsies of skeletal muscle taken from patients with chronic critical limb ischaemia (CLI) and non-ischaemic control subjects. PATIENTS AND METHODS: Biopsy of gastrocnemius muscle was obtained from six patients with unreconstructed CLI referred for surgical major amputation. As control, biopsies of six patients undergoing elective knee arthroplasty without evidence of peripheral arterial occlusive disease were taken. The differences in gene expression associated with angiogenic processes in specimens obtained from ischaemic and non-ischaemic skeletal muscle were confirmed by quantitative real-time polymerase chain reaction (PCR) analysis. RESULTS: Compared with non-ischaemic skeletal muscle biopsy of chronic-ischaemic skeletal muscle contained 55 significantly up-regulated and 45 down-regulated genes, out of which 64 genes had a known genetic product. Tissue samples of ischaemic muscle were characterized by increased expression of cell survival factors (e. g. tissue factor pathway inhibitor 2) in combination with reduced expression of cell proliferation effectors (e. g. microfibrillar-associated protein 5 and transferrin receptor). The expression of growth factors (e. g. early growth response 3 and chemokine receptor chemokine C-X-C motif ligand 4) which play a central role in arterial and angiogenic processes and anti-angiogenetic factors (e. g. pentraxin 3) were increased in chronic ischaemic skeletal muscle. An increased expression of extracellular matrix proteins (e. g. cysteine-rich angiogenic inducer 61) was also observed. CONCLUSIONS: Gene expression profiles in biopsies of gastrocnemius muscle in patients with chronic critical limb ischaemia showed an increase in pro-survival factors, extracellular matrix protein deposition, and impaired proliferation, compared with non-ischaemic controls. Further studies are required to analyse the endogenous repair mechanism.

Indication Criteria for Total Knee Arthroplasty in Patients with Osteoarthritis - A Multi-perspective Consensus Study.

Background and Objectives Knee osteoarthritis (OA) is a significant public health burden. Rates of total knee arthroplasty (TKA) in OA vary substantially between geographical regions, most likely due to the lack of standardised indication criteria. We set out to define indication criteria for the German healthcare system for TKA in patients with knee OA, on the basis of best evidence and transparent multi-stakeholder consensus. Methods We undertook a complex mixed methods study, including an iterative process of systematic appraisal of existing evidence, Delphi consensus methods and stakeholder conferences. We established a consensus panel representing key German national societies of healthcare providers (orthopaedic surgeons, rheumatologists, pain physicians, psychologists, physiotherapists), payers, and patient representatives. A priori defined consensus criteria were at least 70% agreement and less than 20% disagreement among the consensus panel. Agreement was sought for (1) core indication criteria defined as criteria that must be met to consider TKA in a normal patient with knee OA, (2) additional (not obligatory) indication criteria, (3) absolute contraindication criteria that generally prohibit TKA, and (4) risk factors that do not prohibit TKA, but usually do not lead to a recommendation for TKA. Results The following 5 core indication criteria were agreed within the panel: 1. intermittent (several times per week) or constant knee pain for at least 3 - 6 months; 2. radiological confirmation of structural knee damage (osteoarthritis, osteonecrosis); 3. inadequate response to conservative treatment, including pharmacological and non-pharmacological treatment for at least 3 - 6 months; 4. adverse impact of knee disease on patient's quality of life for at least 3 - 6 months; 5. patient-reported suffering/impairment due to knee disease. Additional indication criteria, contraindication criteria, and risk factors for adverse outcome were also agreed by a large majority within the multi-perspective stakeholder panel. Conclusion The defined indication criteria constitute a prerequisite for appropriate provision of TKA in patients with knee OA in Germany. In eligible patients, shared-decision making should eventually determine if TKA is performed or not. The next important steps are the implementation of the defined indication criteria, and the prospective investigation of predictors of success or failure of TKA in the context of routine care provision in Germany.

No difference in range of motion between ultracongruent and posterior stabilized design in total knee arthroplasty: a randomized controlled trial.

PURPOSE: The use of an ultracongruent (UC) insert with a standard femoral component for substitution of the posterior cruciate ligament (PCL) is a bone-preserving and therefore interesting alternative to the established box and cam mechanism of posterior stabilized (PS) total knee arthroplasty (TKA). This study investigated range of motion (ROM), stability and patient-reported outcome (PRO) in UC and PS TKA. We hypothesized better knee flexion with the PS design but no difference in stability and PRO between UC and PS TKA. METHODS: A randomized controlled study was performed. One hundred and twenty-seven patients were included, 63 with an UC and 64 with a PS TKA (Columbus, Aesculap, Tuttlingen, Germany). Intraoperative stability and range of motion was measured with the use of a navigation system. Patients were assessed before surgery, 3 months and 1 year postoperatively. RESULTS: There was no difference in ROM between both groups, neither intraoperatively nor at follow-up. There was 5 mm less sagittal translation at 90° of knee flexion (p < 0.001) and more posterior femoral rollback during knee flexion in the PS TKA. Axial rotation between extension and knee flexion was reduced by both designs. UC TKA was 7 min faster (p = 0.001). At the one-year follow-up, the Knee Society Score was similar in both groups, the Oxford Knee Score demonstrated better results in the UC TKA group (p = 0.048). CONCLUSION: Increased intraoperative sagittal translation and reduced posterior femoral rollback during knee flexion of UC TKA seem to have no negative influence on short-term clinical outcome. Therefore, UC TKA seems to be a practical alternative to the established PS TKA for substitution of the PCL. This might be especially interesting for surgeons who do not always substitute the PCL. LEVEL OF EVIDENCE: I.

How Much Improvement in Patient Activity Can Be Expected After TKA?

Most patients expect an improvement of physical activity after total knee arthroplasty (TKA). The aim of this study was to evaluate improvement in physical activity after TKA. An accelerometer was used to measure activity in 221 patients before and 1 year after TKA. The measurements included the total number of steps and time spent lying, sitting/standing, or walking. Threshold for achievement of health-enhancing physical activity (HEPA) guidelines and step-defined lifestyle were applied to the data. Measured steps per day improved from 5371 to 6587. Only 50 patients (22.6%) met the HEPA guidelines, whereas 31% achieved an active lifestyle. Improvement in daily step number was influenced by age (P<.001), body mass index (P<.001) and preoperative activity (P<.001). After TKA, patients improved in physical activity and one-third achieved an active lifestyle. Patient-specific characteristics and preoperative levels of physical activity had a relevant influence on activity after TKA. [Orthopedics. 2016; 39(3):S18-S23.].

Midterm Results After Coated and Uncoated TKA: A Randomized Controlled Study.

Patients undergoing total knee arthroplasty (TKA) who have hypersensitivity to metals usually receive hypoallergenic TKA implants. Coating of a standard implant is a common solution. Although in vitro tests have demonstrated reduction in polyethylene wear for these coatings, it is unknown whether these costly implants have a clinical benefit for patients. One hundred twenty patients undergoing TKA were randomly assigned to receive a novel 7-layer-coating implant or a standard TKA implant. One revision occurred in the standard group, resulting in a calculated 5-year survival of 100% in the coated group and 98.1% in the standard group. The Oxford Knee Score improved substantially in both groups from a mean of 21.6 points preoperatively in the coated group and 21.9 points in the standard group to 39.2 points and 39.2 points, respectively. The current authors observed no adverse effects with the new coating during midterm follow-up. However, longer follow-up time is needed to evaluate possible advantages of this coating. [Orthopedics. 2016; 39(3):S13-S17.].

The influence of optimism on functionality after total hip replacement surgery.

Among other factors, optimism has been shown to significantly influence the course of some diseases (cancer, HIV, coronary heart disease). This study investigated whether optimism of a patient before a total hip replacement can predict the functionality of the lower limbs 3 and 6 months after surgery. A total of 325 patients took part in the study (age: 58.7 years; w: 55%). The functionality was measured with the Western Ontario and McMaster Universities arthrosis index, and optimism with the Life Orientation Test. To analyse the influences of age, gender and optimism, general linear models were calculated. In optimistic patients, functionality improved significantly over time. The study showed a clear influence of dispositional optimism on the recovery after total hip replacement in the first 3 months after surgery.

Patient-reported outcomes and outcome predictors after primary total hip arthroplasty: results from the Dresden Hip Surgery Registry.

PURPOSE: To investigate response rates and predictors of treatment success in patients treated with total hip arthroplasty (THA). METHODS: A prospective register-based cohort study including all consecutive primary THAs was conducted -between 01/2006-12/2011. Primary outcomes were changes in WOMAC, according to OMERACT-OARSI, and minimal important difference (MID) in quality of life (EQ-5D) between baseline and 6-month follow-up. Socioeconomic and clinical predictors on treatment success were analysed by bivariate/multivariate regression. RESULTS: The study population included 2,553 patients (mean age 60.8 years; 52.8% female) and 2,391 (93.7%) at follow-up. 2,194 (93.8%) (OMERACT-OARSI) and 2,131 (83.5%) (EQ-5D MID) patients were classified as responders. Predictors for treatment success vs treatment failure were not identified. Obese patients and patients living alone showed less pronounced, and patients with higher educational level more pronounced, improvements in the WOMAC at follow-up. CONCLUSIONS: Treatment with THA leads to improvement in function, decline in pain and increase in quality of life in the vast majority of patients.

Effect of surgical experience on imageless computer-assisted femoral component positioning in hip resurfacing--a preclinical study.

BACKGROUND: The clinical outcome of hip resurfacing (HR) as a demanding surgical technique associated with a substantial learning curve depends on the position of the femoral component. The aim of the study was to investigate the effects of the level of surgical experience on computer-assisted imageless navigation concerning precision of femoral component positioning, notching, and oversizing rate, as well as operative time. METHODS: Three surgeons with different levels of experience in both HR and computer-assisted surgery (CAS) prepared the femoral heads of 54 synthetic femurs using the Durom(TM) Hip Resurfacing (Zimmer, Warsaw, IN, USA) system. Each surgeon prepared a total of 18 proximal femurs using the Navitrack® system (ORTHOsoft Inc., Montreal, Canada) or the conventional free-hand Durom(TM) K-wire positioning jig. The differences between planned and postoperative stem shaft angle (SSA) and anteversion angle in standardized x-rays were measured and the operative time, not including the time for calibrating the CAS-system, was documented. Notching was evaluated by the three surgeons in a randomized manner. Oversizing was determined by the difference of the preoperative determined cap and the cap size advised by the CAS-system. RESULTS: CAS significantly reduced the overall mean deviation between planned and postoperative SSA in comparison with the conventional procedure (mean ± SD, 1 ± 1.7° vs. 7.4 ± 4.4°, P < 0.01) regardless of the surgeon's level of experience. The incidence of either varus or valgus SSA deviations exceeding 5° were 1/27 for CAS and 15/27 for the conventional method, respectively (P < 0.001), corresponding to a reduction by 97%. Using CAS, the rate of notching was reduced by 100%. CONCLUSIONS: The accuracy of femoral HR component orientation is significantly increased by use of CAS regardless of the surgeon's level of experience in our preclinical study. Thus, imageless computer-assisted navigation can be a valuable tool to improve implant positioning in HR for surgeons at any stage of their learning curve.

Patient activity after TKA depends on patient-specific parameters.

BACKGROUND: Most patients expect an improvement of walking ability and an increase in activity levels after TKA. Unfortunately, few studies report qualitative and quantitative activity improvements after TKA. QUESTIONS/PURPOSES: The aims of this study were (1) to evaluate quantity and quality of physical activity before and after TKA with an accelerometer, and to compare activity level with that of an age-matched control group without lower-extremity disorders. (2) Improvement in measured steps per day after TKA and the ability to meet physical activity guidelines were evaluated. (3) The influence of patient-specific and implant parameters were assessed. PATIENTS AND METHODS: An accelerometer was used to measure activity in 97 patients who were assessed before TKA and 1 year after TKA. The measurements included the total number of steps, moderate to vigorous activity defined as at least 100 steps per minute, and time spent lying, sitting/standing, or walking. We then calculated the proportion of patients who met the 10,000 steps per day guideline recommendation and determined factors that predicted failure to meet that goal. Thirty-nine age-matched control subjects without lower-extremity disorders were selected and underwent the same assessments using the accelerometer for comparison with patients 1 year after TKA. RESULTS: Measured steps per day improved from a mean of 5278 (SD, 2999) preoperatively to 6473 (SD, 3654) postoperatively (effect size, 1.23; 95% CI, 1.10-1.35; p < 0.001). Moderate to vigorous steps per day improved from a mean of 1150 (SD, 982) to 1935 (SD, 1728; p < 0.001). Times spent in lying, sitting, or standing position or during walking did not change after TKA. For all measured parameters, activity of the patients after TKA was considerably less than that of the age-matched control subjects, who walked a mean of 13,375 (SD, 4614) steps per day (p < 0.001), performed a mean of 6562 (SD, 3401) vigorous steps per day (p < 0.001), and spent a mean of 2.9 hours (SD, 1.1) per day walking (p < 0.001). Only 16 patients (16.5%) met physical activity guidelines after TKA. BMI (p = 0.017), sex (p = 0.027), and comorbidities (American Society of Anesthesiologists Grade, p = 0.042) were independent factors associated with steps per day after TKA. CONCLUSIONS: One year after TKA, patients had increased walking and moderate to vigorous steps. However, only 16.5% achieved the guideline recommendations for walking activity. BMI, sex, and comorbidities are patient factors that are associated with activity after TKA. Even with improvements in walking, activity level after TKA remains less than that seen for age-matched control subjects. Surgeons should be aware of this when counseling patients undergoing TKA. LEVEL OF EVIDENCE: Level III, therapeutic study. See the Instructions for Authors for a complete description of levels of evidence.

Placement makes a difference: accuracy of an accelerometer in measuring step number and stair climbing.

UNLABELLED: Accurate and easy-to-use measurement tools are required to evaluate the effect of treatments on patient activity. Comfortable device placement and fixation are important for patient compliance. The aim of this study was the evaluation of the accuracy of an accelerometer at different placements and slow velocities. METHODS: A total of 43 healthy volunteers were included for a literature-based treadmill protocol using five accelerometer positions; a subset of 18 volunteers performed an extended treadmill protocol with velocities between 0.1 and 2.6m/s and finally stair climbing. RESULTS: An alternative accelerometer position at the anterolateral aspect of the middle shank did measure steps more accurately than at the manufacturer suggested position, especially during slow velocities. Participants preferred the alternative placement at the shank. The accuracy of different accelerometer positions was excellent at velocities between 1.0 and 2.2m/s. During slow velocities below 1.0m/s steps were recorded less accurately. Accepting an error of five percent, the accelerometer recorded steps accurately from 0.5m/s at the alternative placement and from 0.8m/s at the manufacturer suggested placement. Stair climbing was not recorded accurately by any accelerometer position. CONCLUSION: For measuring step number during slow velocities, the alternative position should be favoured. Stair climbing was not recorded accurately by any tested placement.

Is range of motion after cruciate-retaining total knee arthroplasty influenced by prosthesis design? A prospective randomized trial.

Improvement in knee flexion is a major expectation for many patients undergoing total knee arthroplasty (TKA). One hundred and twenty two patients were randomized to receive a cruciate-retaining standard or high-flexion TKA. Range of motion (ROM) and functional outcomes were assessed. The high flexion implants had a greater intraoperative ROM than standard implants. The mean flexion preoperatively, intraoperatively and at the one year follow-up was 107.4°, 123.0° and 108.9° in the standard group and 109.9°, 129.1° and 109.7° in the high-flexion TKA group. These differences were not significant preoperatively and at follow-up, but intraoperatively (P < 0.001). In multivariate analysis preoperative knee flexion was the only significant factor influencing knee flexion at follow-up. No differences in the Knee Society Score or SF 36 were observed.

An epidemiological investigation of training and injury patterns in triathletes.

Associated with the trend towards increased health consciousness and fitness, triathlon has established itself as a sport for masses. The goals of this study were to evaluate injury risk factors of non-professional triathletes and to compare prospective and retrospective evaluation methods. Using an online survey, 212 triathletes retrospectively answered a questionnaire about their training habits and injuries during the past 12 months. Forty-nine of these triathletes participated in a 12-month prospective trial. Injuries were classified with regard to the anatomical location, type of injury, incidence and associated risk factors. Most injuries occurred during running (50%) followed by cycling (43%) and swimming (7%). Fifty-four per cent (retrospective) and 22% (prospective) of the injuries were contusions and abrasions, 38% (retrospective) and 46% (prospective) were ligament and capsular injuries, 7% (retrospective) and 32% (prospective) were muscle and tendon injuries and 1% (retrospective) and 0% (prospective) were fractures. The incidence of an injury per 1000 training hours was 0.69 (retrospective) and 1.39 (prospective) during training and 9.24 (retrospective) and 18.45 (prospective) during competition. The main risk factor for injury in non-professional triathlon is participation in a competitive triathlon event. A retrospective design may underestimate the rate of overuse injuries.

Agreement between radiological and computer navigation measurement of lower limb alignment.

PURPOSE: Accurate and reproducible measurements of limb alignment are necessary for planning, performing and evaluation of reconstructive knee surgery. Aim of this study was the comparison of the alignment measured on long-leg standing radiographs with the intraoperative data from a navigation system. METHODS: The records of 135 consecutive patients who received computer-assisted TKA were examined. Technical quality of the long-leg radiographs (LLRs) was classified good, acceptable or poor according to the rotation of the leg. The difference between radiographic and navigation measurements of leg alignment was assessed. RESULTS: Preoperative LLRs were rated as good 56.3% (71.1% postoperatively), acceptable in 37.0% (20.0% postoperatively) and poor in 6.7% (8.9% postoperatively). The median difference between radiographic and navigation measurements increased with reduced quality of the LLR [good 1.5° (range 0.0°-9.9°), acceptable 2.5° (range 0.0°-15.0°), poor 4.5° (range 0.2°-9.5°)], but not with greater deformity. Median difference between both measurements in good radiographs was 1.7° (range 0.0°-9.9°) preoperatively and 1.2° (range 0.0°-7.0°) postoperatively. CONCLUSION: Difference between radiographic and navigation measurements of lower limb alignment is low if the LLR are obtained in neutral rotation. Larger differences between both measurements can occur even under these ideal conditions, and it is still unclear which measurement is closer to reality. Therefore, even if a navigation system is used during surgery, long-leg standing radiographs should currently not be abandoned. LEVEL OF EVIDENCE: III.

Physical examination tests for the diagnosis of posterior cruciate ligament rupture: a systematic review.

STUDY DESIGN: Systematic literature review. OBJECTIVES: To summarize and evaluate research on the accuracy of physical examination tests for diagnosis of posterior cruciate ligament (PCL) tear. BACKGROUND: Rupture of the PCL is a severe knee injury that can lead to delayed rehabilitation, instability, or chronic knee pathologies. To our knowledge, there is currently no systematic review of studies on the diagnostic accuracy of clinical examination tests to evaluate the integrity of the PCL. METHODS: A comprehensive systematic literature search was conducted in MEDLINE from 1946, Embase from 1974, and the Allied and Complementary Medicine Database from 1985 until April 30, 2012. Studies were considered eligible if they compared the results of physical examination tests performed in the context of a PCL physical examination to those of a reference standard (arthroscopy, arthrotomy, magnetic resonance imaging). Methodological quality assessment was performed by 2 independent reviewers using the revised version of the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. RESULTS: The search strategy revealed 1307 articles, of which 11 met the inclusion criteria for this review. In these studies, 11 different physical examination tests were identified. Due to differences in study types, different patient populations, and methodological quality, meta-analysis was not indicated. Presently, most physical examination tests have not been evaluated sufficiently enough to be confident in their ability to either confirm or rule out a PCL tear. CONCLUSIONS: The diagnostic accuracy of physical examination tests to assess the integrity of the PCL is largely unknown. There is a strong need for further research in this area. Level of Evidence Diagnosis, level 3a.