Shoulder biomechanics in normal and selected pathological conditions

The stability of the glenohumeral joint depends on soft tissue stabilizers, bone morphology and dynamic stabilizers such as the rotator cuff and long head of the biceps tendon. Shoulder stabilization techniques include anatomic procedures such as repair of the labrum or restoration of bone loss, but also non-anatomic options such as remplissage or tendon transfers.Rotator cuff repair should restore the cuff anatomy, reattach the rotator cable and respect the coracoacromial arch whenever possible. Tendon transfer, superior capsular reconstruction or balloon implantation have been proposed for irreparable lesions.Shoulder rehabilitation should focus on restoring balanced glenohumeral and scapular force couples in order to avoid an upward migration of the humeral head and secondary cuff impingement. The primary goal of cuff repair is to be as anatomic as possible and to create a biomechanically favourable environment for tendon healing

Image‐guided percutaneous cryoablation of unresectable sacrococcygeal chordoma: Feasibility and outcome in a selected group of patients with long term follow‐up

Chordoma is a rare malignant tumor of the axial skeleton. Percutaneous cryoablation (PCA) is a minimally invasive technique that allows freezing of tumors under imaging control. The purpose of our retrospective study was to investigate the outcome of PCA in a selected cohort of patients with sacrococcygeal chordoma, with a minimum of 5 years follow-up. Four patients were treated in 10 sessions. The mean follow-up was 57.3 months. We evaluated the feasibility, the procedure-related complications, the impact on pain control and oncological outcomes. Freezing of 100% of the tumor volume was possible in 60%. Pain control was not reliably evaluable. Local recurrence occurred in 90% of the treated lesions; the mean time to progression was 8.1 months (range 1.5-16). At last follow-up, one patient had died of the disease, one of another cause and one was receiving the best supportive care. The only patient alive without the disease had received additional carbon-ion radiotherapy. The 5-year survival rate after index PCA was 50%. Complete freezing of the tumor was technically challenging, mainly due to the complex local anatomy. Recurrence occurred in 90% of the lesions treated. PCA should be considered with caution in the curative management of sacrococcygeal chordoma

Image quality and radiation dose comparison of prospectively triggered low-dose CCTA: 128-slice dual-source high-pitch spiral versus 64-slice single-source sequential acquisition

Currently 64-multislice computed tomography (MSCT) scanners are the most widely used devices allowing low radiation dose coronary CT angiography (CCTA) with prospective ECG triggering. Latest 128-slice dual-source CT (DSCT) scanners offer prospective high-pitch spiral acquisition covering the heart during one single beat. We compared radiation dose and image quality from prospective 64-MSCT versus high-pitch spiral 128-slice DSCT scanning, as such data is lacking. CCTA of 50 consecutive patients undergoing 128-DSCT (2×64×0.6mm collimation, 0.28s rotation time, 3.4 pitch, 100-120kV tube voltage and 320mAs tube current-time product) were compared to CCTA of 50 heart rate (HR) and BMI matched patients undergoing 64-MSCT (64×0.625mm collimation, 0.35s rotation time, 100-120kV tube voltage and 400-650mA tube current). Image quality was rated on a 4-point scale by two independent cardiac imaging physicians (1=excellent to 4=non-diagnostic). Of 710 coronary segments assessed on 128-DSCT, 216 (30.4%) achieved an image quality score 1 excellent, 400 (56.3%) score 2, 76 (10.7%) score 3 and 18 (2.6%) score 4 (non-diagnostic). Of 737 coronary segments evaluated on 64-MSCT 271 (36.8%) had an image quality score of 1, 327 (44.4%) 2, 110 (14.9%) score 3, and 29 (3.9%) segments score 4. Average image quality score for both scanners was similar (P=0.641). The mean heart rate during scanning was 58.7±5.6bpm on 128-DSCT and 59.0±5.6bpm on 64-MSCT, respectively. Mean effective radiation dose was 1.0±0.2mSv for 128-DSCT and 1.7±0.6mSv for 64-MSCT (P<0.001). 128-DSCT with high-pitch spiral mode allows CCTA acquisition with reduced radiation dose at maintained image quality compared to 64-MSC

Antalgie préhospitalière: évaluation et compraison de l'efficacité et de la sécurité de deux protocoles délégués aux ambulanciers

Les ambulanciers jouent un rôle clé dans l'administration précoce d'antalgie dans le système préhospitalier suisse. Les opiacés sont les molécules les plus utilisées dans le cadre de l'antalgie préhospitalière. Il n'existe paradoxalement que peu d'études comparant l'efficacité de différents protocoles délégués aux ambulanciers utilisant le même opiacé. Le service de protection et de sauvetage de Lausanne (SPSL) a modifié en 2005 son protocole d'antalgie initial (Protocole 1) en diminuant de 2 minutes l'intervalle entre 2 doses de morphine ainsi qu'en diminuant la dose de 2.5 à 2mg mais conservant la dose maximum à 10 mg (Protocole 2). Nous avons profité de ce changement pour étudier l'efficacité et la sécurité d'un protocole délégué aux ambulanciers dans un même service d'urgences. Nous avons comparé la proportion de patients avec une échelle verbale numérique d'évaluation de la douleur (EVN) en dessous du barème défini par les protocoles ainsi que l'amplitude de cette diminution lors de l'arrivée des patients aux urgences. Les comparaisons entre les deux protocoles ont été effectuées en utilisant les méthodes de régression standards ainsi que l'appariement des coefficients de propension (propensity score methodology) pour prendre en compte l'effet de regroupement (clustering) des patients par les ambulanciers. Le protocole a été efficace dans 67,9% et 69.8%, l'EVN a diminué de 2.1 et 3.3 ± 2.4 pour les protocoles 1 et 2 respectivement (p = non significatif pour les deux). Avec l'analyse causale utilisant la méthode d'appariement des coefficients de propension et permettant l'élimination des biais inhérents au caractère rétrospectif de l'étude, l'EVN à l'hôpital était de 0.84 (95%IC: 1,66, -0.18; p = 0.04) unité plus faible et le pourcentage de réduction de douleur était de 9% plus important (96%IC: 2%, 17%; p = 0.01) pour le deuxième protocole. La variation entre ambulanciers était significative avec une différence entre 1-2 unités sur l'EVN à l'hôpital. En conclusion l'antalgie déléguée aux ambulanciers est efficace et les modifications du protocole ont mené à une légère amélioration de la gestion de la douleur. Nos résultats montrent une variabilité interpersonnelle significative entre ambulanciers dans la gestion de la douleur. L'étude des facteurs influençant cette variation interpersonnelle pourrait être une opportunité pour améliorer la qualité de la gestion de la douleur en préhospitalier. L'analyse causale utilisée pour comparer les traitements préhopitaliers est une alternative intéressante dans les contextes où une étude randomisée contrôlée est difficile à mettre en œuvre. -- Paramedics play a critical rôle in the early provision of analgesia in the prehospital setting. Opiates are the mainstay of prehospital analgesia, but there are only few studies comparing the efficacy of différent protocols using the same analgésie. The "Service de protection et secours de Lausanne" (SPSL) modified its initial paramedic controlled protocol (Protocol 1), allowing for a 2-minute shorter interval between two doses of morphine (Protocol 2), with a dose réduction from 2.5 to 2 mg with the same maximal dose of 10mg of morphine. We took advantage of this change to evaluate the effectiveness and safety of the two protocols used consecutively in a single emergency médical service. We analyzed the proportion of patients with a verbal numeric rating scale (VNRS) below the predefined threshold and the magnitude of the VNRS réduction on hospital arrivai were compared. Comparisons were performed by standard multilevel régression methods accounting for the clustering of patients by paramedics, and causal analysis methods based on the propensity score methodology. The protocol was successful in 67.9% and 69.8%, and VNRS decreased by 3.3 ± 2.1 and 3.3 ± 2.4 for protocol 1 and 2, respectively (p = not significant for both protocols). However, using causal analysis methods, the VNRS at hospital arrivai was 0.84 (95%CI: 1.66, -0.18; p = 0.04) unit lower and the percentage of pain réduction was about 9% larger (95%CI: 2%, 17%; p = 0.01) for protocol 2. We also found a significant paramedic's effect of c. 1-2 units on the VNRS at hospital. In conclusion our study provides evidence that a paramedic-controlled pain protocol is an efficient and secure option to relieve pain rapidly in the field. Our results demonstrate significant interpersonal variations in pain management practice by paramedics. The study of the déterminant of such variation may represent an opportunity to identify innovative ways to improve the quality of pain management in the prehospital setting. Finally our causal analysis may be used to compare prehospital treatments, when randomized clinical trials are difficult to perform

Knee arthrodesis with modular nail after failed TKA due to infection

Introduction: Knee arthrodesis is an established procedure for limb salvage after failed total knee arthroplasty (TKA) in cases of recurrent infection, soft tissue damage, reduced bone stock or with a deficient extensor mechanism. Walking with an arthrodesis is more efficient and less costly in terms of energy expenditure than above-knee amputation. Surgical options include an arthrodesis nail, external fixator or compression plate. We present our results of knee arthrodesis using the modular Wichita Fusion Nail® in patients after infected TKA. Methods: Fifteen patients with irretrievably failed TKA, due to infection, who underwent arthrodesis with the Wichita Fusion Nail® from 2004 to 2012 were retrospectively reviewed to assess fusion rate, time to fusion, complication rate, including new infections, and ambulatory status. Results: Three patients were lost to follow-up. Mean follow-up was 33months (6-132months). At their most recent follow-up, all patients were walking with full weight bearing on a fused arthrodesis. Mean time to union was 9months (3-29months). Three patients necessitated a revision arthrodesis to achieve union after a mean of 5months after the last procedure. Conclusion: Arthrodesis with the Wichita Fusion Nail® provides satisfactory results in patients with failure after infected TKA, with 75% primary union rate and no new or persistent infection at last follow-up visit. Although burdened with a high complication rate, it represents an acceptable option for limb salvage in this particular pathology

Fractures de l’olécrâne [Olecranon fractures]

Olecranon fractures represent 5 % of all adult fractures. Management is most often surgical. Conservative treatment is recommended for non-displaced fractures or patients who would be poor surgical candidates. Prolonged immobilization of the elbow may cause joint stiffness, whereas surgical treatment can be complicated by loss of reduction or wound issues with secondary infection of the material. In this article, we discuss the pathology and the principles of treatment based on the literature, to allow the general practitioner to guide the patient towards the most suitable treatment

Entrapment of the Sciatic Nerve Over the Femoral Neck Stem After Closed Reduction of a Dislocated Total Hip Arthroplasty

Sciatic nerve injury is a rare but potentially extremely disabling complication of posterior dislocated total hip arthroplasty. Initial closed reduction is recommended followed by a careful neurovascular examination. This procedure and the following stability testing are usually safe and typically associated with a very low complication rate. We report the case of sciatic nerve entrapment around the neck of the femoral stem after closed reduction of a posteriorly dislocated total hip arthroplasty. Immediate postreduction palsy led to surgical exploration, identification, neurolysis of the sciatic nerve and safe reduction was performed. Patient outcome was marked by complete sensitive sciatic nerve recovery, but complete loss of motor sciatic nerve function. This case highlights the importance of careful postreduction neurovascular assessment and prompt surgical exploration when indicated