Nonspecific Thoracic Outlet Syndrome Research Articles

Evaluation of the efficacy of ropivacaine injection in the anterior and middle scalene muscles guided by ultrasonography in the treatment of Thoracic Outlet Syndrome.

A clinical, placebo-controlled, randomized, double-blind trial with two parallel groups. to evaluate the efficacy of ropivacaine injection in each belly of the anterior and middle scalene muscles, guided by ultrasonography, in the treatment of Nonspecific Thoracic Outlet Syndrome (TOS) compared to cutaneous pressure. 38 patients, 19 in the control group (skin pressure in each belly of the anterior and middle scalene muscles) and 19 in the intervention group (ropivacaine). Subjects with a diagnosis of Nonspecific Thoracic Outlet Syndrome, pain in upper limbs and/or neck, with no radiculopathy or neurological involvement of the limb affected due to compressive or encephalic root causes were included. The primary endpoint was functionality, evaluated by the Disabilities of the Arm, Shoulder, and Hand - DASH scale validated for use in Brasil. The time of the evaluations were T0 = before the intervention; T1 = immediately after; T2 = 1 week; T3 = 4 weeks; T4 = 12 weeks; for T1, the DASH scale was not applied. Concerning the DASH scale, it is possible to affirm with statistical significance (p> 0.05) that the intervention group presented an improvement of functionality at four weeks, which was maintained by the 12th week. In practical terms, we concluded that a 0.375% injection of ropivacaine at doses of 2.5 ml in each belly of the anterior and middle scalene muscles, guided by ultrasonography, in the treatment of Nonspecific Thoracic Outlet Syndrome helps to improve function.

Long-term functional outcomes after surgical treatment of nonspecific thoracic outlet syndrome: Retrospective study of 70 cases at a mean of 8 years’ follow-up

Our objective was to study the clinical and functional outcomes after surgical treatment of nonspecific thoracic outlet syndrome (TOS) using a supraclavicular approach. We included every patient with TOS who was treated surgically by the same surgeon at a single hospital between 1999 and 2014 with a minimum follow-up of 4 years. The primary outcome was the overall evaluation of the function by the QuickDASH Score. Secondary outcomes included functional, subjective outcomes, pain levels, and neuropathic features. The clinical outcome of 70 cases was evaluated with a mean follow-up of 8.5 years. The improvement in the QuickDASH Score was significant with an average change of 38 points. Mean pain intensity was reduced postoperatively by 1.6 points from 5.1/10 to 3.5/10. Persistent pain rate at 4/10 or more remained in 56% of cases. These cases were mostly neuropathic. The surgical procedure significantly reduced the number of patients suffering from paresthesia, numbing or weakness. The possibility of sequelae and the persistence of neuropathic pain means the surgical indication should be limited to patients with significant functional disability despite well-conducted rehabilitation. The long-term functional outcomes in patients undergoing TOS was mostly good but could be improved by addressing residual neuropathic pain symptoms.

First Rib Resection for Thoracic Outlet Syndrome: The Robotic Approach.

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®. 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. Median operative time was 108min, and the median hospital stay was 2days. 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 3months after surgery. 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.

Thoracic outlet syndrome

Thoracic outlet syndrome (TOS) is a well-known disorder, but its definition has been disputed. TOS is differentiated into five distinct disorders: arterial vascular, venous vascular, traumatic neurovascular, true neurologic (TN-TOS), and nonspecific TOS. TN-TOS is caused by compression of the lower plexus (T1>C8 roots and/or lower trunk) by a fibrous band. The most frequent presenting symptoms are insidious-onset atrophy and weakness of the intrinsic hand muscles, predominantly in the thenar eminence and radial digital flexors. Numbness and sensory loss are usually present, mainly in the ulnar forearm, although severe pain or pain/paresthesia proximal to the elbow can occur; however, sensory symptoms or signs can be absent in some patients. Nerve conduction studies are pathognomonic and show the loss or severe attenuation of the sensory nerve action potential (SNAP) of the medial antebrachial cutaneous nerve. Additionally, they show a severely depressed median compound muscle action potential (CMAP) and, subsequently, a depressed ulnar CMAP and SNAP. TN-TOS is a rare disorder, although its incidence may be higher than previously believed. Hirayama disease is an important differential diagnosis. Nonspecific TOS, which is mainly diagnosed by provocative maneuvers, corresponds to the classical concept of TOS. However, this concept is now challenged and the existence of nonspecific TOS is doubted.

Thoracic outlet syndrome in 3T MR neurography—fibrous bands causing discernible lesions of the lower brachial plexus

To investigate whether targeted magnetic resonance neurography (MRN) of the brachial plexus can visualise fibrous bands compressing the brachial plexus and directly detect injury in plexus nerve fascicles. High-resolution MRN was employed in 30 patients with clinical suspicion of either true neurogenic thoracic outlet syndrome (TOS) or non-specific TOS. The protocol for the brachial plexus included a SPACE (3D turbo spin echo with variable flip angle) STIR (short tau inversion recovery), a sagittal-oblique T2-weighted (T2W) SPAIR (spectral adiabatic inversion recovery) and a 3D PDW (proton density weighted) SPACE. Images were evaluated for anatomical anomalies compressing the brachial plexus and for abnormal T2W signal within plexus elements. Patients with abnormal MR imaging findings underwent surgical exploration. Seven out of 30 patients were identified with unambiguous morphological correlates of TOS. These were verified by surgical exploration. Correlates included fibrous bands (n = 5) and pseudarthrosis or synostosis of ribs (n = 2). Increased T2W signal was detected within compressed plexus portion (C8 spinal nerve, inferior trunk, or medial cord) and confirmed the diagnosis. The clinical suspicion of TOS can be diagnostically confirmed by MRN. Entrapment of plexus structures by subtle anatomical anomalies such as fibrous bands can be visualised and relevant compression can be confirmed by increased T2W signal of compromised plexus elements. • MR neurography (MRN) can aid the diagnosis of thoracic outlet syndrome (TOS). • Identifiable causes of TOS in MRN include fibrous bands and bony anomalies. • Increased T2W signal within brachial plexus elements indicate relevant nerve compression. • High positive predictive value allows confident and targeted indication for surgery.

Doppler Adson’s Test: Predictor of Outcome of Surgery in Non‐Specific Thoracic Outlet Syndrome

Outcome of surgery in non-specific thoracic outlet syndrome (TOS) is variable. Duplex imaging of the subclavian artery during Adson's maneuvre may help predict outcome. A retrospective study of 16 cases of non-specific TOS who had pre-operative duplex imaging of the subclavian artery during Adson's maneuvre was done and their outcomes following surgical decompression of the thoracic outlet studied. Of the eight cases with a positive Adson's test, seven (87.5%) had a complete response of symptoms following surgery while in the eight cases with a negative test, only four (50%) had a favorable response to surgery. Duplex scanning of the thoracic outlet during Adson's maneuvre may help predict outcome of thoracic outlet decompression surgery in cases of non-specific TOS.

Outcome of surgery for thoracic outlet syndrome in Washington state workers’ compensation

To determine the predictors of outcome of thoracic outlet syndrome (TOS) surgery in a population-based cohort of injured workers. All injured workers in the Washington State Workers' Compensation system who received TOS surgery during 1986 to 1991 were identified by computerized bill payment records and validated by medical record review (n = 158). The main outcome measure was work disability status 1 year after surgery. Additional functional status and quality of life outcomes were determined by telephone survey an average of 4.8 years after operation. A sample of workers with a TOS diagnosis who did not receive surgery during 1987 to 1989 were identified as a comparison group (n = 95). Sixty percent of workers were still work disabled 1 year after surgery. The strongest predictors of remaining disabled were the amount of work disability before surgery (OR = 1.85; 95% CI, 1.51 to 2.28), longer time between injury and TOS diagnosis (OR = 1.34; 95% CI, 1.09 to 1.64), and older age at injury (OR = 1.07; 95% CI, 1.00 to 1.13). There was no relationship between type of surgery, presence of any provocative tests, or experience of surgeon and work disability outcome. In follow-up surveys an average of 4.8 years after surgery, 72.5% of workers still reported they were "limited a lot" in vigorous activities. Compared with a nonsurgical sample of TOS patients, those receiving surgery had 50% greater medical costs and were three to four times more likely to be work disabled. The outcome of TOS surgery among injured workers is worse than has generally been reported. The nonspecific neurogenic TOS diagnosis, the complexity of workers' compensation cases, and the adverse event profile are likely substantial contributors to the worse outcomes reported here. Well-designed prospective studies and randomized trials are required to elucidate any role of TOS surgery in nonspecific TOS.