Neurogenic thoracic outlet syndrome

Surgical Management of Neurogenic Thoracic Outlet Syndrome: Exploring the Efficacy of the Posterior Intermuscular Approach in Cases Involving Bone Anomalies

BACKGROUND AND OBJECTIVES

This article presents a cohort study focusing on neurogenic thoracic outlet syndrome (NTOS) caused by bone anomalies in the cervicothoracic region, specifically the extraforaminal area and the scalene triangle. Our aim was to contribute to understanding NTOS diagnosis and management, particularly in patients with bone anomalies, and to highlight the potential benefits of the posterior intermuscular approach as a surgical option in this particular patient group.

METHODS

We retrospectively evaluated the patients who underwent surgery for NTOS with accessory ribs or an elongated cervical vertebrae 7 (C7) transverse process (n = 9). Patients' clinical data, preoperative neurophysiological tests, cervical computed tomography (CT) scans, CT angiography, and postoperative cervical CT scans were reviewed. A single experienced surgeon used the posterior intermuscular approach on all patients. The accessory rib and/or elongated C7 transverse process and fibrous bands were removed; C7, C8, and T1 branches of the plexus were decompressed; and neurolysis was performed. Quality of life, a functional outcome, was measured by using Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire, and pain was measured using visual analog scale scores.

RESULTS

The mean follow-up time after surgery was 7 months (range: 4-10 months). Before surgery, the mean DASH score was 55.8 ± 5.6. At the 3- and 6-month postoperative evaluations, the mean DASH scores decreased to 15.7 ± 5.8 and 15.4 ± 5.7, respectively. The mean visual analog scale score was 8.2/10 before surgery and decreased to 2.4/10 and 2.1/10 at the 3- and 6-month postoperative evaluations, respectively. All patients experienced good or excellent recovery at the 3- and 6-month postoperative evaluations.

CONCLUSION

Cervicothoracic extraforaminal area may be the primary site of nerve compression in NTOS, and posterior decompression using the posterior intermuscular approach can provide efficient access to extraforaminal nerve roots.

Outcomes of 53 thoracic outlet syndrome cases with confirmed neurological deficit

INTRODUCTION

Neurogenic thoracic outlet syndromes (TOS) are dominated by the nonspecific forms. This study focuses only on the rarer true forms related to proximal nerve compression in the thoracic outlet, with the presence of motor (atrophy of the hand's intrinsic muscles) and/or sensory (hypoesthesia in the territory of the medial antebrachial cutaneous nerve) deficits. The objectives of this study were to define the clinical characteristics, anatomical causes and surgical results of this condition.

PATIENTS AND METHODS

Single-center retrospective study of 53 consecutive cases in 50 patients with an objective clinical deficit confirmed by nerve conduction studies. The population consisted of 47 adults and 3 children, 9 males and 41 females, with a mean age of 39 years (9-80 years), diagnosed between July 1994 and December 2019. An objective motor deficit was present in 50 cases, with the remaining 3 having a sensory deficit only. Forty cases underwent surgery, most often via the supraclavicular approach, while 13 cases did not undergo surgery because their deficit was longstanding and non-progressive.

RESULTS

One operated patient was lost in follow-up. An analysis of the medical records of 18 cases, including 15 operated cases found complete recovery in 4 cases, significant improvement in 9 cases and small improvement in 2 cases at a mean follow-up of 53 months (1-162 months). Thirty-four cases were reviewed in person, including 24 operated cases and evaluated with a mean follow-up of 135 months (36-284 months): the pain had disappeared in 21 cases, thenar atrophy persisted in 17 cases, which was associated with a claw-hand deformity in 3 cases, while 2 cases had an isolated claw-hand deformity. The patients were very satisfied with the procedure in 15 cases and satisfied in 9 cases. They evaluated the benefit of surgery at 87% and their upper limb function increased from 38% (10-60%) preoperatively to 77% (60-100%) at the review.

CONCLUSION

Few studies in the literature have focused on true neurogenic TOS cases. The treatment is surgical in progressive cases; an anatomical anomaly is always present. Surgical treatment eliminates the pain and helps to stabilize or even partially resolve the deficit. Despite a moderate objective gain, the patients' feeling of functional improvement is important with a high satisfaction rate.

LEVEL OF EVIDENCE

IV, retrospective.

Normal Costoclavicular Distance as a Standard in the Radiological Evaluation of Thoracic Outlet Syndrome in the Costoclavicular Space

BACKGROUND

The costoclavicular space is a common site of thoracic outlet syndrome. When there is no anatomical alteration, the diagnosis of thoracic outlet syndrome is difficult. Several authors relate costoclavicular distance to symptoms of thoracic outlet syndrome; however, there is no standardized site for measurement of the costoclavicular distance. This study aimed to determine the standard costoclavicular distance at neurovascular bundle crossing points (near the subclavian vein [Measure V] and the subclavian artery/brachial plexus branches [Measure NA]) using high-resolution chest computed tomography (CT) scans and evaluate its variations with respect to age, sex, height, and body mass index.

METHODS

This prospective cross-sectional observational study analyzed 150 of 156 CT scans from consecutive adult patients (72 females and 78 males). Costoclavicular distance was measured at the subclavian vein and brachial plexus/subclavian artery sites, where narrowing of the costoclavicular distance could lead to symptoms of thoracic outlet syndrome. Costoclavicular distance was analyzed with respect to sex, laterality, age group (<50 and ≥50 years) and body mass index group (body mass index <25 and ≥25 kg/m²).

RESULTS

Measures of V and NA were normally distributed. The measured costoclavicular distances were 1.23 cm (±0.40) and 1.24 cm (±0.47), respectively. Age (≥50 years) and body mass index (≥25 kg/m²) increased the costoclavicular distance. Measurements V and NA below the fifth percentile indicated a narrowed costoclavicular distance and a greater chance of developing thoracic outlet syndrome. For young (<50 years) and eutrophic patients (body mass index <25 kg/m²), these measurements were 0.46 and 0.44 cm, respectively; for young people and body mass index ≥25 kg/m², they were 0.54 and 0.24 cm, respectively; for the elderly (≥50 years) and eutrophic, they were 0.57 and 0.48 cm, respectively; and for the elderly and body mass index ≥ 25 kg/m², they were 0.83 and 0.73 cm, respectively. There was no significant difference between measurements V and NA regarding patient laterality, gender, and height.

CONCLUSIONS

Standardization of costoclavicular distance measurements at neurovascular bundle crossing points (subclavian vein and brachial plexus/subclavian artery) is possible. It may aid the diagnosis and help direct the therapeutic indications for symptomatic patients with thoracic outlet syndrome.

Outcomes of Surgical Management of Neurogenic Thoracic Outlet Syndrome: A Systematic Review and Bayesian Perspective

PURPOSE

To provide a summary of the relevant evidence on outcomes of transaxillary first rib excision (TAFRE), supraclavicular first rib excision with scalenectomy (SCFRE), and supraclavicular release leaving the first rib intact (SCR) for patients with neurogenic thoracic outlet syndrome (TOS), and interpret the treatment effects from a Bayesian perspective.

METHODS

A systematic literature search and review were performed. Random-effects meta-analyses were conducted to estimate success rate and complete relief rate of each procedure. The probabilities of specified success rates and complete relief rates were calculated using a Bayesian method. Sensitivity analyses for TOS type, neck trauma, and cervical rib were performed. Complications of each procedure were also reviewed.

RESULTS

Data were extracted from 17 studies of TAFRE, 9 of SCFRE, and 14 of SCR to conduct the meta-analyses. The pooled success rate and complete relief rate were 0.76 (95% confidence interval [95% CI)], 0.65-0.85) and 0.53 (95% CI, 0.38-0.68) for TAFRE, 0.77 (95% CI, 0.68-0.85) and 0.57 (95% CI, 0.41-0.72) for SCFRE, and 0.85 (95% CI, 0.76-0.92) and 0.61 (95% CI, 0.35-0.84) for SCR, respectively. The probabilities of success rate greater than 70% were 90%, 87%, and 99% for TAFRE, SCFRE, and SCR, respectively. If the success rate of 80% or greater was considered, the probabilities were 34%, 31%, and 91%, respectively. The probabilities of complete relief rate of 50% or greater were 67%, 71%, and 69% for TAFRE, SCFRE, and SCR, respectively. Sensitivity analyses showed similar results. The complication rates for TAFRE, SCFRE, and SCR were, respectively, 22.5%, 25.9%, and 12.6%.

CONCLUSIONS

The SCR has a high probability of success rate greater than 80%; both TAFRE and SCFRE have high probabilities of a success rate greater than 70% but only low probabilities of success rate greater than 80%. The TAFRE and SCFRE have more complications than SCR.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Cervical Rib Prevalence and its Association with Thoracic Outlet Syndrome: A Meta-Analysis of 141 Studies with Surgical Considerations

BACKGROUND

Cervical ribs (CR) are supernumerary ribs that arise from the seventh cervical vertebra. In the presence of CR, the boundaries of the interscalene triangle can be further constricted and result in neurovascular compression and thoracic outlet syndrome (TOS). The aim of our study was to provide a comprehensive evidence-based assessment of CR prevalence and their association with TOS as well as surgical approach to excision of CR and surgical patients' characteristics.

METHODS

A thorough search of major electronic databases was conducted to identify any relevant studies. Data on the prevalence, laterality, and side of CR were extracted from the eligible studies for both healthy individuals and patients with TOS. Data on the type of TOS and surgical approach to excision of CR were extracted as well.

RESULTS

A total of 141 studies (n = 77,924 participants) were included into the meta-analysis. CR was significantly more prevalent in patients with TOS than in healthy individuals, with pooled prevalence estimates of 29.5% and 1.1%, respectively. More than half of the patients had unilateral CR in both the healthy and the TOS group. The analysis showed that 51.3% of the symptomatic patients with CR had vascular TOS, and 48.7% had neurogenic TOS. Most CR were surgically excised in women using a supraclavicular approach.

CONCLUSIONS

CR ribs are frequent findings in patients with TOS. We recommended counseling asymptomatic patients with incidentally discovered CR on the symptoms of TOS, so that if symptoms develop, the patients can undergo prompt and appropriate workup and treatment.

Work-Related Neurogenic Thoracic Outlet Syndrome: Diagnosis and Treatment

Outcomes of surgery for neurogenic thoracic outlet syndrome (NTOS) in workers' compensation are poor in a majority of patients, partly due to nonspecificity of diagnosis. Most cases have no objective evidence of the presence of brachial plexus dysfunction. Up to 20% of patients experience a new adverse event. Objective neurologic signs and electrodiagnostic evidence of brachial plexus dysfunction must be present before proceeding with invasive procedures. This guideline includes objective criteria that must be met before thoracic outlet syndrome surgery can be approved in Washington State. Evidence does not support the use of scalene blocks, botulinum toxin therapy, or vascular studies to diagnose NTOS.

Treatment for thoracic outlet syndrome

BACKGROUND

Thoracic outlet syndrome (TOS) is one of the most controversial diagnoses in clinical medicine. Despite many reports of operative and non-operative interventions, rigorous scientific investigation of this syndrome leading to evidence-based management is lacking. This is the first update of a review first published in 2010.

OBJECTIVES

To evaluate the beneficial and adverse effects of the available operative and non-operative interventions for the treatment of TOS a minimum of six months after the intervention.

SEARCH METHODS

On 23 June 2014 we searched the Cochrane Neuromuscular Disease Group Trials Specialized Register, CENTRAL, The Database of Abstracts of Reviews of Effects (DARE), MEDLINE, EMBASE, CINAHL Plus and AMED. We also searched reference lists of the identified trials.

SELECTION CRITERIA

We selected randomized or quasi-randomized studies involving participants with the diagnosis of TOS of any type (neurogenic, vascular, and 'disputed'), without limitations as to language of publication.We accepted studies that examined any intervention aimed at treating TOS.The primary outcome measure was change in pain rating, measured on a validated visual analog or similar scale at least six months after the intervention.The secondary outcomes were change in muscle strength, disability, experiences of paresthesias (numbness and tingling sensations), and adverse effects of the interventions.

DATA COLLECTION AND ANALYSIS

Three authors independently selected the trials to be included and extracted data. Authors rated included studies for risk of bias, according to the methods recommended in the Cochrane Handbook for Systematic Reviews of Interventions.

MAIN RESULTS

This review was complicated by a lack of generally accepted criteria for the diagnosis of TOS and had to rely exclusively on the diagnosis of TOS by the investigators in the reviewed studies. We identified one study comparing natural progression with an active intervention. We found three randomized controlled trials (RCTs), but only two of them had a follow-up of six months or more, which was the minimum required follow-up for inclusion in the review. The first trial that met our requirements involved 55 participants with the 'disputed type' of TOS and compared transaxillary first rib resection (TFRR) with supraclavicular neuroplasty of the brachial plexus (SNBP). The trial had a high risk of bias. TFRR decreased pain more than SNBP. There were no adverse effects in either group. The second trial that met these requirements analyzed 37 people with TOS of any type, comparing treatment with a botulinum toxin (BTX) injection into the scalene muscles with a saline placebo injection. This trial had a low risk of bias. There was no significant effect of treatment with the BTX injection over placebo in terms of pain relief or improvements in disability, but it did significantly improve paresthesias at six months' follow-up. There were no adverse events of the BTX treatment above saline injection.

AUTHORS' CONCLUSIONS

This review was complicated by a lack of generally accepted diagnostic criteria for the diagnosis of TOS. There was very low quality evidence that transaxillary first rib resection decreased pain more than supraclavicular neuroplasty, but no randomized evidence that either is better than no treatment. There is moderate evidence to suggest that treatment with BTX injections yielded no great improvements over placebo injections of saline. There is no evidence from RCTs for the use of other currently used treatments. There is a need for an agreed definition for the diagnosis of TOS, especially the disputed form, agreed outcome measures, and high quality randomized trials that compare the outcome of interventions with no treatment and with each other.

NTOS symptoms and mobility: a case study on neurogenic thoracic outlet syndrome involving massage therapy

Neurogenic thoracic outlet syndrome (NTOS) is a neuromuscular condition affecting brachial plexus functionality. NTOS is characterized by paresthesia, pain, muscle fatigue, and restricted mobility in the upper extremity. This study quantified massage therapy's possible contribution to treatment of NTOS. A 24-year-old female with NTOS received eight treatments over 35 days. Treatment included myofascial release, trigger point therapy, cross fiber friction, muscle stripping, and gentle passive stretching. Abduction and lateral rotation at the glenohumeral (GH joint) assessments measured range of motion (ROM). A resisted muscle test evaluated upper extremity strength. The client rated symptoms daily via a visual analog scale (VAS). Findings showed improvement in ROM at the GH joint. VAS ratings revealed a reduction in muscle weakness, pain, numbness, and 'paresthesia'. Results suggest massage may be useful as part of a broad approach to managing NTOS symptoms and improving mobility.

Thoracic outlet syndrome: a neurological and vascular disorder

Thoracic outlet syndrome (TOS) is a condition arising from compression of the subclavian vessels and/or brachial plexus as the structures travel from the thoracic outlet to the axilla. Despite the significant pathology associated with TOS, there remains some general disagreement among experts on the specific anatomy, etiology, and pathophysiology of the condition, presumably because of the wide variation in symptoms that manifest in presenting patients, and because of lack of a definitive gold standard for diagnosis. Symptoms associated with TOS have traditionally been divided into vascular and neurogenic categories, a distinction based on the underlying structure(s) implicated. Of the two, neurogenic TOS (nTOS) is more common, and typically presents as compression of the brachial plexus; primarily, but not exclusively, involving its lower trunk. Vascular TOS (vTOS) usually involves compression of the vessel, most commonly the subclavian artery or vein, or is secondary to thrombus formation in the venous vasculature. Any anatomical anomaly in the thoracic outlet has the potential to predispose a patient to TOS. Common anomalies include variations in the insertion of the anterior scalene muscle (ASM) or scalenus minimus muscle, the presence of a cervical rib or of fibrous and muscular bands, variations in insertion of pectoralis minor, and the presence of neurovascular structures, which follow an atypical course. A common diagnostic technique for vTOS is duplex imaging, which has generally replaced more invasive angiographic techniques. In cases of suspected nTOS, electrophysiological nerve studies and ASM blocks provide guidance when screening for patients likely to benefit from surgical decompression of TOS. Surgeons generally agree that the transaxillary approach allows the greatest field of view for first rib excision to relieve compressed vessels. Alternatively, a supraclavicular approach is favored for scalenotomies when the ASM impinges on surrounding structures. A combined supraclavicular and infraclavicular approach is preferred when a larger field of view is required. The future of TOS management must emphasize the improvement of available diagnostic and treatment techniques, and the development of a consensus gold standard for diagnosis. Helical computed tomography offers a three-dimensional view of the thoracic outlet, and may be valuable in the detection of anatomical variations, which may predispose patients to TOS. This review summarizes the history of TOS, the pertinent clinical and anatomical presentations of TOS, and the commonly used diagnostic and treatment techniques for the condition.

Diagnostic pitfalls in spine surgery: masqueraders of surgical spine disease

Disorders of the spine are common in clinical medicine, and spine surgery is being performed with increasing frequency in the US. Although many patients with an established diagnosis of a true surgically treatable lesion are referred to a neurosurgeon, the evaluation of patients with spinal disorders can be complex and fraught with diagnostic pitfalls. While “common conditions are common,” astute clinical acumen and vigilance are necessary to identify lesions that masquerade as surgically treatable spine disease that can lead to erroneous diagnosis and treatment. In this review, the authors discuss musculoskeletal, peripheral nerve, metabolic, infectious, inflammatory, and vascular conditions that mimic the syndromes produced by surgical lesions. It is possible that nonsurgical and surgical conditions coexist at times, complicating treatment plans and natural histories. Awareness of these diagnoses can help reduce diagnostic error, thereby avoiding the morbidity and expense associated with an unnecessary operation.

What's new in the diagnosis and treatment of peripheral nerve entrapment neuropathies

Entrapment neuropathies can be common conditions with the potential to cause significant disability. Correct diagnosis is essential for proper management. This article is a review of recent developments related to diagnosis and treatment of various common and uncommon nerve entrapment disorders. When combined with classical peripheral nerve examination techniques, innovations in imaging modalities have led to more reliable diagnoses. Moreover, innovations in conservative and surgical techniques have been controversial as to their effects on patient outcome, but randomized controlled trials have provided important information regarding common operative techniques. Treatment strategies for painful peripheral neuropathies are also reviewed.

Treatment for thoracic outlet syndrome

BACKGROUND

Thoracic outlet syndrome (TOS) is one of the most controversial clinical entities in medicine. Despite many reports of operative and non-operative interventions, rigorous scientific investigation of this syndrome leading to evidence based management is lacking.

OBJECTIVES

To evaluate the beneficial and adverse effects of the available operative and non-operative interventions for the treatment of thoracic outlet syndrome.

SEARCH STRATEGY

We searched the Cochrane Neuromuscular Disease Group Trials Specialized Register (July 2009), The Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 2, 2009), MEDLINE (January 1966 to June 2009), EMBASE (January 1980 to June 2009), CINAHL (January 1981 to June 2009 ), AMED (January 1985 to June 2009 ) and reference lists of articles.

SELECTION CRITERIA

We selected randomized or quasi-randomized studies in any language of participants with the diagnosis of any type of thoracic outlet syndrome (neurogenic, vascular, and 'disputed'). The primary outcome measure was change in pain rating on a validated visual analog or similar scale at least six months after the intervention. The secondary outcomes were change in muscle strength and adverse effects of the interventions.

DATA COLLECTION AND ANALYSIS

Four authors independently selected the trials to be included and extracted data. The one included study was rated for risk of bias according to the methods recommended in the Cochrane Handbook for Systematic Reviews of Interventions.

MAIN RESULTS

This review was complicated by a lack of generally accepted criteria for the diagnosis of TOS and had to rely exclusively on the diagnosis of TOS by the investigators in the reviewed studies. There were no studies comparing natural progression with any active intervention. In one trial with a high risk of bias involving 55 participants transaxillary first rib resection decreased pain more than supraclavicular neuroplasty of the brachial plexus. There were no adverse effects in either group.

AUTHORS' CONCLUSIONS

This review was complicated by a lack of generally accepted diagnostic criteria for the diagnosis of TOS. There was very low quality evidence that transaxillary first rib resection decreased pain more than supraclavicular neuroplasty but no randomized evidence that either is better than no treatment. There is no randomized evidence to support the use of other currently used treatments. There is a need for an agreed definition for the diagnosis of TOS, especially the disputed form, agreed outcome measures and high quality randomized trials that compare the outcome of interventions with no treatment and with each other.

Thoracic outlet syndrome part 1: clinical manifestations, differentiation and treatment pathways

Thoracic outlet syndrome (TOS) is a challenging condition to diagnose correctly and manage appropriately. This is the result of a number of factors including the multifaceted contribution to the syndrome, the limitations of current clinical diagnostic tests, the insufficient recognition of the sub-types of TOS and the dearth of research into the optimal treatment approach. This masterclass identifies the subtypes of TOS, highlights the possible factors that contribute to the condition and outlines the clinical examination required to diagnose the presence of TOS.

Exercise-induced scalenus syndrome

BACKGROUND

Thoracic outlet syndrome is described as a group of distinct disorders producing signs and symptoms attributed to compression of nerves and blood vessels in the thoracic outlet region.

PURPOSE

To describe the exercise-induced scalenus anticus syndrome attributed to the anterior scalenus hypertrophy as a thoracic outlet syndrome underlying mechanism and to give recommendations for a safe and effective surgical treatment.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Twelve young professional athletes admitted for thoracic outlet syndrome (8 cases of neurologic thoracic outlet syndrome, 4 cases of mixed neurologic and vascular thoracic outlet syndrome) who reported numbness, tingling, early fatigue, muscle weakness, and pain were enrolled in the study. Scalenus hypertrophy was suspected to be the causative factor. Scalenectomy was performed in all cases.

RESULTS

All patients had moderate to severe hypertrophy of the anterior scalenus muscle. Scalenectomy was performed, and there were no intraoperative or postoperative complications. Full activity was quickly achieved, and no recurrence of symptoms was documented.

CONCLUSION

Surgical intervention for scalenus anticus syndrome can allow an athlete to return to full activity and improve quality of life. Surgical intervention seems to be the treatment of choice in terms of restoring quality of life and physical activity.