To the Editor, Neurovascular bundle positional compression can be asymptomatic (thoracic outlet compression: TOC) or symptomatic (thoracic outlet syndrome: TOS).1,2 Arterial compression assessed in patients suffering neural TOS is associated with a more favorable postsurgical outcome.3 To date, no questionnaire focuses on self-reported arterial type symptoms in patients with TOS. Arterial type characteristics have been defined at the lower limb level4 but scarcely at the upper limb level.5,6 We tested the feasibility of an original thoracic and upper limb pain (TULIP) questionnaire inspired by standard lower limb tools.4 We included all patients that were referred with suspected TOS. We sought to estimate the proportion of patients who exhibited upper limb symptoms consistent with typical arterial type characteristics. Exclusion criteria: Age <18 years old and non-French native language. Individual informed written consent was not required according to French legislation. If not declining participation, patients were asked to complete the TULIP, while waiting in the waiting room Figure 1. We also recorded clinical parameters and the results of electroneuromyography (EMG), ultrasound (US) imaging, or injected arterial radiological imaging (angiography or computed tomography angiography or angio-magnetic resonance imaging) performed in the 6 months before or after inclusion consistent with the presence or absence of TOC.Figure 1: Experimental design and thoracic and upper limb pain questionnaire used in the study. Any pain related to the exercise was considered present if the respondent answered “yes” to either the “systematic” or “sometimes” questionsFor the analyses, incorrect filling of the TULIP included the absence of, or double response, to one of the 5 first ITEMS (Q1 to Q5) or obvious errors on the side to be encoded in item 6 compared to the side reported during the visit. Patients, who reported no pain at rest and exercise, were recognized as asymptomatic. Patients that reported exercise-related pain without pain at rest, but that was not delayed from exercise onset, or delayed symptoms that did not persist throughout exercise, or whose symptoms persisted throughout exercise but persisted more than 10 min after exercise were classified as “exercise-induced pain.” All statistical analyses were performed with IBM SPSS Statistics software, version 15.0 (Chicago, NY, USA). Statistical significance was a two-tailed probability level of P < 0.05 and not significant results reported: “NS.” From September 2020 to October 2023, 197 symptomatic and 3 asymptomatic patients were included. Eight had Paget Schroetter or McCleery syndrome and one had arterial digital embolism. All other patients were clinically suspected of neurogenic origin. Last, 85 had upper limb comorbid conditions. Illustration of TULIP responses is shown in Figure 2.Figure 2: Responses to the thoracic and upper limb pain (TULIP) questionnaire (upper panel) and of the number of times (a “X” was placed by the patients on each area of the TULIP figures (lower left panel) and number of “X” reported on the figures by each patient (lower right panel)Table 1 reports the patient characteristics by symptom type.Table 1: A description of the 197 symptomatic patients is provided, organized by symptom characteristicsResults of US, EMG, and/or angiography are illustrated in Table 2.Table 2: Symptomatic patients. Relative risk of positive results using Chi-square tests results with Significacy results in italics (when at least one of these investigations is available)The prevailing view is that, in the absence of vascular complications, TOS should be classified as neural in origin,1 resulting in arterial TOS (a-TOS) prevalence being from 1% to 3% of all TOS.7,8 The ~20% prevalence of arterial-type symptoms among our patients is consistent with the prevalence of coexisting arterial compression in n-TOS previously reported3 and the fact that ischemia may contribute to 22.2% of symptoms in patients with suspected TOS.9 We also reiterate our claim that the possibility of arterial ischemia or venous edema contributing to pain should not be ruled out solely on the basis that these patients do not have vascular complications.2 Our results supported that the use of the TULIP helps indicate an arterial characteristic of pain,9 although it provides no example of the type of exercise/position inducing symptoms and is not specific to TOS. It is crucial to highlight that the presence of symptoms in the upper limbs, despite apparently normal investigations, could potentially result from isolated venous or neural TOC. In addition, these symptoms could also be attributed to osteo-articular issues that are not directly related to the TOC. As the present study focused on feasibility, future studies must evaluate the content validity, construct validity, responsiveness, validity and reliability, and sensitivity to changes of the TULIP questionnaire, before it can be proposed for clinical use. Last, it could be argued that patients with confirmed TOS should have been the focus of the study, rather than those with suspected TOS. Nevertheless, TOS remains a holistic diagnosis, and the presence of a comorbid condition does not preclude the possibility of TOS. Inversely, confirmed TOS cannot be only operated patients, since all patients with TOS do not undergo surgery. According to the TULIP questionnaire, 20% of all patients referred for suspected TOS have symptoms consistent with upper limb arterial-type symptoms, which is much higher than the 3% prevalence a-TOS reported in the literature. Analysis of other populations, comparison to other questionnaires and/or ability of the TULIP results to predict treatment efficiency, are interesting questions for future studies. Ethical approval Local registering: ID-RCB: 2022-A01451-42 CPP (Comité de Protection des Personnes) approval 12/07/2022, Ethics Committee approval February 04, 2020 under reference: 2020/17 Clinicaltrial.gov declaration: NCT04376177. Data management with “Methodology of Reference” (MR-003) number 1985224. Availability of data and materials Data will be provided following reasonable request to the authors. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.
Lecoq et al. (Wed,) studied this question.