Epidemiologic study of low back pain in 1398 Swiss conscripts between 1985 and 1992.

The two objectives of this study, based on a sample of 1398 Swiss army conscripts born in 1966 who participated in a first study in 1985, were to measure the prevalence of low back pain (LBP) at age 26 years and its incidence between 19 and 26 years and to analyze the relationship between LBP and occupational, nonoccupational, or physical risk factors. The lifetime prevalence of LBP at age 26 was 69.1% and the incidence of LBP between 19 and 26, 44.7%. A history of LBP or a pathological physical examination result at age 19 did not predict the prevalence or the incidence at age 26. Standing, twisting, vibration, and heavy work were significantly associated with chronic LBP and/or the 1-year prevalence of LBP at age 26 (P < 0.05). The evolution of sport and leisure-time activities from age 19 to 26 did not differ between people with or without LBP. The ergonomic organization of the workplace should represent a major element of future strategies to prevent LBP.

Characteristics and outcome of knee prosthetic joint infections (PJI): A 10-year cohort study (2000-2009)

Background: Prosthetic joint infections (PJI) lead to significant long-term morbidity with high cost of healthcare. We evaluated characteristics of infections and the infection and functional outcome of knee PJI over a 10-year period. Methods: All patients hospitalized at our institution from 1/2000 through 12/2009 with knee PJI (defined as growth of the same microorganism in ≥2 tissue or synovial fluid cultures, visible purulence, sinus tract or acute inflammation on tissue histopathology) were included. Patients, their relatives and/or treating physicians were contacted to determine the outcome. Results: During the study period, 61 patients with knee PJI were identified. The median age at the time of diagnosis of infection was 73 y (range, 53-94 y); 52% were men. Median hospital stay was 37 d (range, 1-145 d). Most reasons for primary arthroplasty was osteoarthritis (n = 48), trauma (n = 9) and rheumatoid arthritis (n = 4). 23 primary surgeries (40%) were performed at CHUV, 34 (60%) elsewhere. After surgery, 8 PJI were early (<3 months), 16 delayed (3-24 months) and 33 late (>24 months). PJI were treated with (i) open or arthroscopic debridement with prosthesis retention in 26 (46%), (ii) one-stage exchange in 1, (iii) two-stage exchange in 22 (39%) and (iv) prosthesis removal in 8 (14%). Isolated pathogens were S. aureus (13), coagulase-negative staphylococci (10), streptococci (5), enterococci (3), gram-negative rods (3) and anaerobes (3). Patients were followed for a median of 3.1 years, 2 patients died (unrelated to PJI). The outcome of infection was favorable in 50 patients (88%), whereas the functional outcome was favorable in 33 patients (58%). Conclusions: With the current treatment concept, the high cure rate of infection (88%) is associated with a less favorable functional outcome o 58%. Earlier surgical intervention and more rapid and improved diagnosis of infection may improve the functional outcome of PJI.

Previous microvascular decompression decreases the chances of pain free in patients treated with Gamma Knife radiosurgery for TIC

Object: The authors sought to establish whether the safety-efficacy of Gamma Knife radiosurgery (GKRS) as a second treatment for intractable trigeminal neuralgia (ITN) are influenced by prior microvascular decompression (MVD) which remains, for some of the authors, the reference technique. Methods: Between July 1992 and November 2010, 737 patients have been operated with GKRS for ITN and prospectively evaluated in Timone University Hospital in Marseille, France. Among these, 54 patients had a previous MVD history. Radiosurgery using a Gamma Knife (model B or C or Perfexion) was performed relying on both MR and CT targeting. A single 4 mm isocenter was positioned in the cisternal portion of the trigeminal nerve at a median distance of 7.6 mm (range 3.9- 11.9) anteriorly to the emergence of the nerve (retrogasserian target). A median maximum dose of 85 Gy (range 70-90) was delivered. Are further analyzed only 45 patients with previous MVD and a follow-up longer than one year (the patients with megadolichobasilar artery compression and multiple sclerosis were excluded). Results: The median age in this series was 56.75 years (range 28.09-82.39). The median follow-up period was 39.48 months (range 14.10-144.65). All the patients had a past history of surgery, with at least one previous failed MVD, but also a radiofrequency lesion (RFL) in 16 (35.6%) patients, balloon microcompression in 7 (15.6%) patients and glycerol rhizotomy in 1 case (2.2%). Thirty-five patients (77.8%) were initially pain free in a median time of 14 days (range 0, 180). Patients from this group had less probability of being pain free compared to our global population of essential trigeminal neuralgia without previous MVD history (p=0.010, hazard ratio of 0.64). Their probability of remaining pain free at 3, 5, 7 and 10 years was 66.5%, 59.1%, 59.1% and 44.3%, respectively. Twelve patients (34.3%) initially pain free experienced a recurrence with a median delay of 31.21 months (range 3.40-89.93). The hypoesthesia actuarial rate at 1 year was 9.1% and remained stable till 12 years with a median delay of onset of 8 months (range 8-8). Conclusions: Retrogasserian GKRS proofed to be safe and effective on the long-term basis even after failed previous MVD. Even if the initial result of pain free was of only 77.8%, the toxicity was low with only 9.1% hypoesthesia. No patient reported a bothersome hypoesthesia. The probability of maintaining pain relief in long-term was of 44.3% at 10 years.

Direct magnetic resonance arthrography of the knee: utility of axial traction.

The purpose of this study was to determine the impact of axial traction during acquisition of direct magnetic resonance (MR) arthrography examination of the knee in terms of joint space width and amount of contrast material between the cartilage surfaces. Direct knee MR arthrography was performed in 11 patients on a 3-T MR imaging unit using a T1-weighted isotropic gradient echo sequence in a coronal plane with and without axial traction of 15 kg. Joint space widths were measured at the level of the medial and the lateral femorotibial joint with and without traction. The amount of contrast material in the medial and lateral femorotibial joint was assessed independently by two musculoskeletal radiologists in a semiquantitative manner using three grades ('absence of surface visualization, 'partial surface visualization or 'complete surface visualization'). With traction, joint space width increased significantly at the lateral femorotibial compartment (mean = 0.55 mm, p = 0.0105) and at the medial femorotibial compartment (mean = 0.4 mm, p = 0.0124). There was a trend towards an increased amount of contrast material in the femorotibial compartment with axial traction. Direct MR arthrography of the knee with axial traction showed a slight and significant increase of the width of the femorotibial compartment with a trend towards more contrast material between the articular cartilage surfaces.

Ruling out coronary heart disease in primary care patients with chest pain: a clinical prediction score.

ABSTRACT: BACKGROUND: Chest pain raises concern for the possibility of coronary heart disease. Scoring methods have been developed to identify coronary heart disease in emergency settings, but not in primary care. METHODS: Data were collected from a multicenter Swiss clinical cohort study including 672 consecutive patients with chest pain, who had visited one of 59 family practitioners' offices. Using delayed diagnosis we derived a prediction rule to rule out coronary heart disease by means of a logistic regression model. Known cardiovascular risk factors, pain characteristics, and physical signs associated with coronary heart disease were explored to develop a clinical score. Patients diagnosed with angina or acute myocardial infarction within the year following their initial visit comprised the coronary heart disease group. RESULTS: The coronary heart disease score was derived from eight variables: age, gender, duration of chest pain from 1 to 60 minutes, substernal chest pain location, pain increases with exertion, absence of tenderness point at palpation, cardiovascular risks factors, and personal history of cardiovascular disease. Area under the receiver operating characteristics curve was of 0.95 with a 95% confidence interval of 0.92; 0.97. From this score, 413 patients were considered as low risk for values of percentile 5 of the coronary heart disease patients. Internal validity was confirmed by bootstrapping. External validation using data from a German cohort (Marburg, n = 774) revealed a receiver operating characteristics curve of 0.75 (95% confidence interval, 0.72; 0.81) with a sensitivity of 85.6% and a specificity of 47.2%. CONCLUSIONS: This score, based only on history and physical examination, is a complementary tool for ruling out coronary heart disease in primary care patients complaining of chest pain.

Paroxysmal Extreme Pain Disorder (PEPD): clinical and genetic investigation

Objectifs 1) Caractériser une famille avec PEPD aux plans clinique, généalogique et génétique. 2) Identifier la cause génétique de la maladie dans cette famille, et en démontrer la pathogénicité. Introduction Le "Paroxysmal Extreme Pain Disorder " (PEPD) est une maladie génétique de transmission autosomique dominante caractérisée par des douleurs paroxystiques rectales, oculaires, maxillaires ou dans les membres inférieurs, qui peuvent être accompagnées d'un érythème. Les épisodes sont déclenchés par le contact cutané, les traumatismes mineurs et l'exposition au chaud. Leur intensité est telle qu'elle en est invalidante. PEPD est causé par des mutations du gène SCN9A, qui code pour la sous-unité alpha du canal sodique Nav1.7. Ce canal est distribué dans des cellules nerveuses périphériques appelées "nocicepteurs" qui sont impliquées dans la transmission du signal lié à la douleur. Méthode et Résultats Résultats Cliniques La partie clinique s'est déroulée à l'aide d'interviews structurées par visite directe, entretiens téléphoniques ou par correspondance. L'anamnèse, les données généalogiques et l'examen clinique ont été étudiés de façon extensive et tabulée. Résultats Génétiques Suite à l'identification de la mutation, un génotypage a été effectué à l'aide de techniques standards, afin de démontrer la co-ségrégation de la mutation avec la maladie. En outre, un groupe contrôle de 92 sujets suisses sans maladie connue ont été génotypés pour exclure la possibilité d'un polymorphisme rare. Grâce aux techniques de PCR et de séquençage, nous avons pu démontrer la présence d'une nouvelle mutation hétérozygote dans l'exon 27 du gène SCN9A, ce dernier étant impliqué dans plusieurs maladies dont PEPD. Cette mutation est codante, et conduit à un changement d'acide aminé dans le canal sodique Nav1.7 (mutation p.L1612P). Conclusions L'étude démontre la présence d'une nouvelle mutation du gène SCN9A permettant d'expliquer les symptômes décrits dans la famille investiguée. En effet, le groupe contrôle et tous les individus non symptomatiques de la famille n'ont pas la mutation, ce qui soutient fortement sa pathogénicité. En outre, il s'agit d'une mutation codante non-synonyme, localisée à proximité d'autres mutations causales précédemment étudiées au plan électrophysiologique.

Sedation and analgesia for colonoscopy: patient tolerance, pain, and cardiorespiratory parameters.

BACKGROUND: Colonoscopy is generally performed with the patient sedated and receiving analgesics. However, the benefit of the most often used combination of intravenous midazolam and pethidine on patient tolerance and pain and its cardiorespiratory risk have not been fully defined. METHODS: In this double-blind prospective study, 150 outpatients undergoing routine colonoscopy were randomly assigned to receive either (1) low-dose midazolam (35 micrograms/kg) and pethidine (700 micrograms/kg in 48 patients, 500 micrograms/kg in 102 patients), (2) midazolam and placebo pethidine, or (3) pethidine and placebo midazolam. RESULTS: Tolerance (visual analog scale, 0 to 100 points: 0 = excellent; 100 = unbearable) did not improve significantly more in group 1 compared with group 2 (7 points; 95% confidence interval [-2-17]) and group 3 (2 points; 95% confidence interval [-7-12]). Similarly, pain was not significantly improved in group 1 as compared with the other groups. Male gender (p < 0.001) and shorter duration of the procedure (p = 0.004), but not amnesia, were associated with better patient tolerance and less pain. Patient satisfaction was similar in all groups. Oxygen desaturation and hypotension occurred in 33% and 11%, respectively, with a similar frequency in all three groups. CONCLUSIONS: In this study, the combination of low-dose midazolam and pethidine does not improve patient tolerance and lessen pain during colonoscopy as compared with either drug given alone. When applying low-dose midazolam, oxygen desaturation and hypotension do not occur more often after combined use of both drugs. For the individual patient, sedation and analgesia should be based on the endoscopist's clinical judgement.

Indicators used by clinicians to assess pain in the brain injured

INTRODUCTION. The assessment of pain in critically ill brain-injured patients is challenging for health professionals. In addition to be unable to self-report, the confused and stereotyped behaviors of these patients are likely to alter their ''normal'' pain responses. Therefore, the pain indicators observed in the general critically ill population may not be appropriate. OBJECTIVES. To identify behavioral and physiological indicators used by clinicians to assess pain in critically ill brain-injured patients who are unable to self-report. METHODS.Amixed-method design was used with the first step being the combination of the results of an integrative literature review with the results of nominal groups of 12 nurses and four physicians. The second step involved a web-based survey to establish content validity. Fourteen experts (clinicians and academics) from three French speaking European countries rated the relevance of each indicator. A content validity index (CVI) was computed for each indicator (I-CVI) and for each category (S-CVI). RESULTS. The first step generated 52 indicators. These indicators were classified into six categories: facial expressions, position/movement, muscle tension, vocalization, compliance with ventilator, and physiological indicators. In the second step, the agreement between raters was high with an Intraclass Correlation Coefficient of 0.88 (95% CI 0.83-0.92). The I-CVIs ranged from 0.07 to 1. Indicators with an I-CVI below 0.5 (n = 12) were not retained, resulting in a final list of 30 indicators. The CVI for this final list was 0.75 with categories ranging from 0.67 (compliance with ventilation) to 0.87 (vocalization). CONCLUSIONS. This process identified specific pain indicators for critically ill braininjured patients. Further evaluation is in progress to test the validity and relevance of these indicators in the clinical setting.

Passive knee-extension test to measure hamstring tightness: influence of gravity correction

CONTEXT: A passive knee-extension test has been shown to be a reliable method of assessing hamstring tightness, but this method does not take into account the potential effect of gravity on the tested leg. OBJECTIVE: To compare an original passive knee-extension test with 2 adapted methods including gravity's effect on the lower leg. DESIGN: Repeated measures. SETTING: Laboratory. PARTICIPANTS: 20 young track and field athletes (16.6 ± 1.6 y, 177.6 ± 9.2 cm, 75.9 ± 24.8 kg). INTERVENTION: Each subject was tested in a randomized order with 3 different methods: In the original one (M1), passive knee angle was measured with a standard force of 68.7 N (7 kg) applied proximal to the lateral malleolus. The second (M2) and third (M3) methods took into account the relative lower-leg weight (measured respectively by handheld dynamometer and anthropometrical table) to individualize the force applied to assess passive knee angle. MAIN OUTCOME MEASURES: Passive knee angles measured with video-analysis software. RESULTS: No difference in mean individualized applied force was found between M2 and M3, so the authors assessed passive knee angle only with M2. The mean knee angle was different between M1 and M2 (68.8 ± 12.4 vs 73.1 ± 10.6, P < .001). Knee angles in M1 and M2 were correlated (r = .93, P < .001). CONCLUSIONS: Differences in knee angle were found between the original passive knee-extension test and a method with gravity correction. M2 is an improved version of the original method (M1) since it minimizes the effect of gravity. Therefore, we recommend using it rather than M1.

Consensus interdisciplinaire CHUV-HUG sur la prise en charge des douleurs du dos. Son application lausannoise dans la filière du dos [Inter-hospital CHUV-HUG medical consensus of back pain management. Its application in care pathways within CHUV of Lausanne].

Back pain is a considerable economical burden in industrialised countries. Its management varies widely across countries, including Switzerland. Thus, the University Hospital and University of Lausanne (CHUV) recently improved intern processes of back pain care. In an already existing collaborative context, the two university hospitals in French-speaking Switzerland (CHUV, University Hospital of Geneva), felt the need of a medical consensus, based on a common concept. This inter-hospital consensus produced three decisional algorithms that bear on recent concepts of back pain found in literature. Eventually, a fast track was created at CHUV, to which extern physicians will have an organised and rapid access. This fast track aims to reduce chronic back pain conditions and provides specialised education for general practitioners-in-training.

Pain assessment in PICU and NICU: Have we got it right?

Pain assessment in critically ill infants and nonverbal children remains a challenge for health professionals. Despite the numerous pain observational measures that have been developed or adapted for infants and children with impaired communication, pain prevalence in paediatric and neonatal intensive care unit remains too high. As pain assessment has been recognised as a pre-requisite for appropriate pain management, much effort was put in the validation or the adaptation of pain measures with little emphasis on implementation of these instruments into practice. Only a few studies demonstrated the benefit of using standardised protocols for the management of pain to guide practice with variable effects. When standardised protocols are undeniably useful in practice, they do not replace health professionals' clinical reasoning necessary to care for individuals. The diversity of the PICU population makes that pain scores need to be interpreted within its clinical context. This session will present pain assessment as a complex transaction that describes structured clinical reasoning from expert nurses that goes beyond the "silver" standard of hetero-evaluation of pain in non-communicative children. Besides pain scores, several patients and nurses factors play a major role in making decisions about analgesia and/or sedation. Patient's clinical instability, change in patient's clinical status, source for observed agitated behaviour, patient's known reactions to analgesia and sedation and anticipation of risks are factors that should be taken into account when implementing pain assessment and management guidelines in PICU and NICU.

Effect of tibial tray inclination on the femoro-tibial contact pattern of a mobile total knee arthroplasty

Introduction: The posterior inclination of the tibial component is an important factor that can affect the success of total knee arthroplasty. It can reduce the posterior impingement and thus increase the range of flexion, but it may also induce instability in flexion, anterior impingement between the polyethylene of postero-stabilizing knee prosthesis, and anterior conflict with the cortical bone and the stem. Although the problem is identified, there is still a debate on the ideal inclination angle and the surgical technique to avoid an excessive posterior inclination. The aim of this study was to predict the effect of a posterior inclination of the tibial component on the contact pattern on the tibial insert, using a numerical musculoskeletal model of the knee joint. Methods: A 3D finite element model of the knee joint was developed to simulate an active and loaded squat movement after total knee arthroplasty. Flexion was actively controlled by the quadriceps muscle and muscle activations were estimated from EMG data and were synchronized by a feedback algorithm. Two inclinations of the tibial tray were considered: a posterior inclination of 0° or 10°. During the entire range of flexion, the following quantities were calculated: the tibiofemoral and patello-femoral contact force, and the contact pattern on polyethylene insert. The antero-posterior displacement of the contact pattern was also measured. Abaqus 6.7 was used for all analyses. Results: The tibio-femoral and patello-femoral contact forces increased during flexion and reached respectively 4 and 7 BW (bodyweight) at 90° of flexion. They were slightly affected by the inclination of the tibial tray. Without posterior inclination, the contact pattern on the tibial insert remained centered. The contact pressure was lower than 5 MPa below 60° of flexion, but exceeded 20 MPa at 90° of flexion. The posterior inclination displaced the contact point posteriorly by 2 to 4 mm. Conclusion: The inclination of the tibial tray displaced the contactpattern towards the posterior border of the tibial insert. However, even for 10° of inclination, the contact center remained far from the posterior border (12 mm). There was no instability predicted for this movement.

Epaule douloureuse: prise en charge ambulatoire [Shoulder pain in ambulatory practice].

Scapulalgias or omalgias are a frequent complaint, with more than half of them being linked to an injury of the rotators cuff. As they often become chronic, omalgias result in higher rates of absenteeism and significant health care costs. Scapulalgias have three main causes: posttraumatic, intrinsic of the joint, or extrinsic. The extrinsic omalgias, either of neurologic, cardiovascular, pulmonary, or abdominal etiology, require swift identification, as their treatment is often an emergency. Most of the scapulalgias can be treated conservatively. Main factors of poor prognosis are old age, women gender and associated cervicalgias.