Diagnostic des syndromes du défilécervico-thoraco-brachial : apport de l’artériographieréalisée en position assise

The thoracobrachial outlet syndrome, a false negative on MRI is possible: About a case

The diagnosis of thoracobrachial outlet syndrome is one of the most discussed diagnoses. We report the case of a 33-year-old woman who presented to the consultation for pain, edema, and paresis of the left upper limb. Magnetic resonance imaging makes it possible to make the diagnosis, but it happens in certain situations that it reveals certain limits for the confirmation of this syndrome. This case highlights the false negatives of this examination in front of a very telling clinical picture.

Upper arm versus forearm transcutaneous oximetry during upper limb abduction in patients with suspected thoracic outlet syndrome

Context: Thoracic outlet syndrome (TOS) is common among athletes and should be considered as being of arterial origin only if patients have “clinical symptoms due to documented symptomatic ischemia.” We previously reported that upper limb ischemia can be documented with DROPm (minimal value of limb changes minus chest changes) from transcutaneous oximetry (TcpO2) in TOS.

Purpose: We aimed to test the hypothesised that forearm (F-) DROPm would better detect symptoms associated with arterial compression during abduction than upper arm (U-) DROPm, and that the thresholds would differ.

Methods: We studied 175 patients (retrospective analysis of a cross-sectional acquired database) with simultaneous F-TcpO2 and U-TcpO2 recordings on both upper limbs, and considered tests to be positive (CS+) when upper limb symptoms were associated with ipsilateral arterial compression on either ultrasound or angiography. We determined the threshold and diagnostic performance with a receiver operating characteristic (ROC) curve analysis and calculation of the area under the ROC curve (AUROC) for absolute resting TcpO2 and DROPm values to detect CS+. For all tests, a two-tailed p < 0.05 was considered indicative of statistical significance.

Results: In the 350 upper-limbs, while resting U-TcpO2 and resting F-TcpO2 were not predictive of CS + results, the AUROCs were 0.68 ± 0.03 vs. 0.69 ± 0.03 (both p < 0.01), with the thresholds being −7.5 vs. −14.5 mmHg for the detection of CS + results for U-DROPm vs. F-DROPm respectively.

Conclusion: In patients with suspected TOS, TcpO2 can be used for detecting upper limb arterial compression and/or symptoms during arm abduction, provided that different thresholds are used for U-DROPm and F-DROPm.

Clinical Trial Registration:ClinicalTrials.gov, identifier NCT04376177.

Relationship Between Inflow Impairment and Skin Oxygen Availability to the Upper Limb During Standardized Arm Abduction in Patients With Suspected Thoracic Outlet Syndrome

Objective

Thoracic outlet syndrome (TOS) should be considered of arterial origin only if patients have clinical symptoms that are the result of documented symptomatic ischemia. Simultaneous recording of inflow impairment and forearm ischemia in patients with suspected TOS has never been reported to date. We hypothesized that ischemia would occur in cases of severely impaired inflow, resulting in a non-linear relationship between changes in pulse amplitude (PA) and the estimation of ischemia during provocative attitudinal upper limb positioning.

Design

Prospective single center interventional study.

Material

Fifty-five patients with suspected thoracic outlet syndrome.

Methods

We measured the minimal decrease from rest of transcutaneous oximetry pressure (DROPm) as an estimation of oxygen deficit and arterial pulse photo-plethysmography to measure pulse amplitude changes from rest (PA-change) on both arms during the candlestick phase of a “Ca + Pra” maneuver. “Ca + Pra” is a modified Roos test allowing the estimation of maximal PA-change during the “Pra” phase. We compared the DROPm values between deciles of PA-changes with ANOVA. We then analyzed the relationship between mean PA-change and mean DROPm of each decile with linear and second-degree polynomial (non-linear) models. Results are reported as median [25/75 centiles]. Statistical significance was p < 0.05.

Results

DROPm values ranged −11.5 [−22.9/−7.2] and − 12.3 [−23.3/−7.4] mmHg and PA-change ranged 36.4 [4.6/63.8]% and 38.4 [−2.0/62.1]% in the right and left forearms, respectively. The coefficient of determination between median DROPm and median PA-change was r² = 0.922 with a second-degree polynomial fitting, but only r² = 0.847 with a linear approach.

Conclusion

Oxygen availability was decreased in cases of severe but not moderate attitudinal inflow impairments. Undertaking simultaneous A-PPG and forearm oximetry during the “Ca + Pra” maneuver is an interesting approach for providing objective proof of ischemia in patients with symptoms of TOS suspected of arterial origin.

Thoracic Outlet Syndrome: Fingertip Cannot Replace Forearm Photoplethysmography in the Evaluation of Positional Venous Outflow Impairments

Objective: Fingertip photoplethysmography (PPG) resulting from high-pass filtered raw PPG signal is often used to record arterial pulse changes in patients with suspected thoracic outlet syndrome (TOS). Results from venous (low-pass filtered raw signal) forearm PPG (V-PPG) during the Candlestick-Prayer (Ca + Pra) maneuver were recently classified into four different patterns in patients with suspected TOS, two of which are suggestive of the presence of outflow impairment. We aimed to test the effect of probe position (fingertip vs. forearm) and of red (R) vs. infrared (IR) light wavelength on V-PPG classification and compared pattern classifications with the results of ultrasound (US).

Methods: In patients with suspected TOS, we routinely performed US imaging (US + being the presence of a positional compression) and Ca + Pra tests with forearm V-PPG_IR. We recruited patients for a Ca + Pra maneuver with the simultaneous fingertip and forearm V-PPG_R. The correlation of each V-PPG recording to each of the published pattern profiles was calculated. Each record was classified according to the patterns for which the coefficient of correlation was the highest. Cohen’s kappa test was used to determine the reliability of classification among forearm V-PPG_IR, fingertip V-PPG_R, and forearm V-PPG_R.

Results: We obtained 40 measurements from 20 patients (40.2 ± 11.3 years old, 11 males). We found 13 limbs with US + results, while V-PPG suggested the presence of venous outflow impairment in 27 and 20 limbs with forearm V-PPG_IR and forearm V-PPG_R, respectively. Fingertip V-PPG_R provided no patterns suggesting outflow impairment.

Conclusion: We found more V-PPG patterns suggesting venous outflow impairment than US + results. Probe position is essential if aiming to perform upper-limb V-PPG during the Ca + Pra maneuver in patients with suspected TOS. V-PPG during the Ca + Pra maneuver is of low cost and easy and provides reliable, recordable, and objective evidence of forearm swelling. It should be performed on the forearm (close to the elbow) with either PPG_R or PPG_IR but not at the fingertip level.

Arterial Digital Pulse Photoplethysmography in Patients with Suspected Thoracic Outlet Syndrome: A Study of the "Ca+Pra" Maneuver

The level of pulse amplitude (PA) change in arterial digital pulse plethysmography (A-PPG) that should be used to diagnose thoracic outlet syndrome (TOS) is debated. We hypothesized that a modification of the Roos test (by moving the arms forward, mimicking a prayer position (“Pra”)) releasing an eventual compression that occurs in the surrender/candlestick position (“Ca”) would facilitate interpretation of A-PPG results. In 52 subjects, we determined the optimal PA change from rest to predict compression at imaging (ultrasonography +/− angiography) with receiver operating characteristics (ROC). “Pra”-PA was set as 100%, and PA was expressed in normalized amplitude (NA) units. Imaging found arterial compression in 23 upper limbs. The area under ROC was 0.765 ± 0.065 (p < 0.0001), resulting in a 91.4% sensitivity and a 60.9% specificity for an increase of fewer than 3 NA from rest during “Ca”, while results were 17.4% and 98.8%, respectively, for the 75% PA decrease previously proposed in the literature. A-PPG during a “Ca+Pra” test provides demonstrable proof of inflow impairment and increases the sensitivity of A-PPG for the detection of arterial compression as determined by imaging. The absence of an increase in PA during the “Ca” phase of the “Ca+Pra” maneuver should be considered indicative of arterial inflow impairment.

First Rib Resection for Thoracic Outlet Syndrome: The Robotic Approach

OBJECTIVE

First rib resection is a well-recognized treatment option for thoracic outlet syndrome (TOS). In case of a vascular insufficiency that can be provoked and/or progressive neurologic symptoms without response to conservative treatment, surgical decompression of the space between the clavicle and the first rib is indicated. The aim of this paper is to present our experience with a new minimally invasive robotic approach using the da Vinci Surgical System®.

METHODS

Between January 2015 and October 2017, eight consecutive first rib resections in seven patients were performed at our institution. Four patients presented with neurologic (one bilateral), and three patients with vascular (venous) impairment. In all cases, a transthoracic robotic-assisted approach was used. The first rib was removed using a 3-port robotic approach with an additional 2-cm axillary incision in the first six patients. The latest resection was performed through only three thoracic ports.

RESULTS

Median operative time was 108 min, and the median hospital stay was 2 days. Postoperative courses were uneventful in all patients. Clinical follow-up examinations showed relief of symptoms in all nonspecific TOS patients, and duplex ultrasonography confirmed complete vein patency in the remaining patients 3 months after surgery.

CONCLUSIONS

While there are limitations in conventional transaxillary, subclavicular and supraclavicular approaches in the first rib resection, the robotic method is not only less invasive but also allows better exposure and visualization of the first rib. Furthermore, the technique takes advantage of the benefits of the da Vinci Surgical System® in terms of 3D visualization and improved instrument maneuverability. Our early experience clearly demonstrates these advantages, which are also supported by the very good outcomes.

Dynamic CT angiography for the diagnosis of patients with thoracic outlet syndrome: Correlation with patient symptoms

INTRODUCTION

Vasculo-nervous structures serving the upper limbs may be compressed as they pass through three areas: the inter-scalene triangle (IST), the costo-clavicular space (CCS) and the retropectoralis minor space (RMS). The diagnosis of thoracic outlet syndrome (TOS) is essentially clinical, but requires imaging to specify the site of compression, its grade and the existence of predisposing anatomical factors, in order to guide the treatment and eliminate the main differential diagnoses.

MATERIAL AND METHODS

Images from 141 patients who underwent dynamic CT angiography of the thoracic outlets from June 2008 to January 2015 were analyzed retrospectively. Patients had unilateral or bilateral vascular, neurological, mixed or atypical symptoms. We studied the degree of stenosis of the subclavian artery with the following grading system: 1 (0-<25%), 2 (25-<50%), 3 (50-<75%), 4 (75-100%). The site of stenosis and the presence of underlying anatomical predisposing factors were also taken in account.

RESULTS

A total of 221 thoracic outlets were analyzed. Symptoms were neurological, mixed, vascular and atypical in 30%, 28%, 13% and 12%, respectively. Among patients with bilateral acquisitions, 38 outlets were asymptomatic; 40% of symptomatic outlets and only 5% of asymptomatic ones had grade 3 or 4 stenosis. 63% of the stenosis were in the CCS and 37% in the IST; 21% had a predisposing anatomical factor most often a costo-clavicular anomaly, associated with significant stenosis in 50% of cases.

CONCLUSION

Vascular stenosis of more than 50% on dynamic CT angiography is strongly associated with TOS. Predisposing factors were present in 21% of cases, causing significant vascular stenosis in half, underscoring the need for functional evaluation.

The thoracic outlet syndromes: Part 2. The arterial, venous, neurovascular, and disputed thoracic outlet syndromes

The thoracic outlet syndromes (TOSs) are a group of etiologically and clinically distinct disorders with 1 feature in common: compression of 1 or more neurovascular elements as they traverse the thoracic outlet. The medical literature reflects 5 TOSs: arterial; venous; traumatic neurovascular; true neurogenic; and disputed. Of these, the first 4 demonstrate all of the features expected of a syndrome, whereas disputed TOS does not, causing many experts to doubt its existence altogether. Thus, some categorize disputed TOSs as cervicoscapular pain syndrome rather than as a type of TOS. To better understand these disorders, their distinctions, and the reasoning underlying the categorical change of disputed TOS from a form of TOS to a cervicoscapular pain syndrome, a thorough understanding of the pertinent anatomy, pathology, pathophysiology, and electrodiagnostic manifestations of these pathophysiologies is required. This review of the TOSs is provided in 2 parts. In part 1 we covered general information pertinent to all 5 TOSs and reviewed true neurogenic TOS in detail. In part 2, we review the arterial, venous, traumatic neurovascular, and disputed forms of TOS. Muscle Nerve 56: 663-673, 2017.

[Surgical decompression of a thoracic outlet syndrome]

Le syndrome de défilé thoraco-brachial est une pathologie souvent méconnue à cause de diagnostic difficile par manque des signes pathognomoniques conduisant souvent à des errances. Les manifestations cliniques dépendent selon qu'il s'agit d'une compression nerveuse, vasculaire ou vasculo-nerveuse. Le but de cette étude est de décrire certains aspects cliniques particuliers et évaluer le résultat fonctionnel après la décompression chirurgicale du paquet vasculo-nerveux. Notre étude rétrospective a porté sur l'analyse des données cliniques, radiologiques, IRM et EMG sur les patients opérés entre janvier 2010 et juillet 2013 du syndrome de défilé thoraco-brachial dans le service de traumatologie orthopédie de l'hôpital Ibn Sina de Rabat. 15 cas ont été colligés: 12 cas post traumatiques (fracture de la clavicule) et 3 cas d'origines congénitales, dont l’âge moyen était 35 ans (20 à 50 ans) avec 9 femmes et 6 hommes. A la fin du traitement, le score de Dash est passé de 109 (46% Normal=0) à 70 (20%), et le stress test de Roos était de 70/100 à 80/100. Le résultat était excellent dans 12 cas soit (80%) et moins bon dans dans 3 cas (20%). En définitive, la résection de malformations osseuses, l'excision des brides et la neurolyse du plexus brachial suivie de la rééducation a donné une bonne évolution fonctionnelle.

Thoracic outlet syndrome: a controversial clinical condition. Part 1: anatomy, and clinical examination/diagnosis

Thoracic outlet syndrome (TOS) is a frequently overlooked peripheral nerve compression or tension event that creates difficulties for the clinician regarding diagnosis and management. Investigators have categorized this condition as vascular versus neurogenic, where vascular TOS can be subcategorized as either arterial or venous and neurogenic TOS can subcategorized as either true or disputed. The thoracic outlet anatomical container presents with several key regional components, each capable of compromising the neurovascular structures coursing within. Bony and soft tissue abnormalities, along with mechanical dysfunctions, may contribute to neurovascular compromise. Diagnosing TOS can be challenging because the symptoms vary greatly amongst patients with the disorder, thus lending to other conditions including a double crush syndrome. A careful history and thorough clinical examination are the most important components in establishing the diagnosis of TOS. Specific clinical tests, whose accuracy has been documented, can be used to support a clinical diagnosis, especially when a cluster of positive tests are witnessed.