Scalene muscle abnormalities in traumatic thoracic outlet syndrome

Thoracic outlet syndrome (TOS) is not a single disorder but a collection of abnormalities in the same anatomic area that elicit similar symptoms. The many causes of TOS are best classified into one of three groups: osseous, traumatic, and nontraumatic. Although patients with traumatic TOS constituted 86% of our last 600 patients with TOS who underwent surgical treatment, the precise mechanism underlying the condition remains obscure. To determine if there was microscopic abnormalities, 45 anterior and middle scalene muscles from patients with traumatic TOS were studied by means of histochemical stains applied after freezing of the muscles. The results revealed a consistent abnormal histologic pattern in patients with traumatic TOS: type II fibers were atrophied; there was an increase in the average number of type I fibers (78% versus 53% in muscles from control patients); and there was a significant increase (mean: 36%) in connective tissue (muscles from control patients averaged less than 15%). Although type II fiber atrophy and type I fiber predominance are seen in a variety of other conditions, their association with fibrosis is rare. Following neck injuries, the changes in the anterior and middle scalene muscles are compatible with trauma, suggesting that fibrotic scalene muscles are an important cause of symptoms in traumatic TOS.     

Surgical management of thoracic outlet syndrome: a 10-year experience

BACKGROUND: Thoracic Outlet Syndrome (TOS) refers to compression of the neurovascular structures in the region between the scalene muscles and the first rib, or by anatomical abnormalities such as cervical rib, fibrous bands and other variations in the scalene musculature. METHODS: Our experience with 63 consecutive operations for TOS, over a period of 10 years, has been reviewed. Preoperative symptoms and signs, investigations, surgery done, complications and the outcome of surgery are analysed. RESULTS: A total of 60 patients underwent 63 operations for decompression of TOS. All the 63 first ribs, were excised by the transaxillary approach. In seven patients (16%), a combined transaxillary and supraclavicular approach was used. There was no operative mortality in this series. The operative complications included pneumothorax in four patients (6.3%), which was treated by insertion of chest drain, and lower brachial plexus neuropraxia in two patients (3%), which improved with conservative management. The mean duration of postoperative hospital stay was 3.6 days. At 12 months following surgery, 56 patients (93%) had complete or partial relief of symptoms and only four patients (6.6%) had no relief of symptoms. CONCLUSION: The results of the present study confirm that transaxillary excision of the first rib is a surgical procedure associated with very low morbidity and excellent relief of symptoms. It can therefore be offered as an early option for patients with thoracic outlet syndrome. It may be combined with the supraclavicular approach if exposure of the subclavian artery is required for vascular reconstruction.     

切断前中小斜角肌治疗胸廓出口综合征的远期疗效

目的 远期随访切断前中斜角肌治疗胸廓出口综合征（thoracic outlet syndrome，TOS）的疗效。方法对31例32侧胸廓出口综合征患者术后的疗效作远期随访。其中上干型4例，下干型26例27侧，全臂丛型1例。X线片示颈肋1例。第七颈椎横突过长2例。均行手术治疗。术中发现31例均有纤维束带压迫臂丛神经，作前、中、小前斜角肌切断术；3例骨异常者同时切除增长的骨组织和颈肋。术后随访4年8个月-8年3个月．平均为5年4个月。以症状、体征有无复发以及是否恢复原工作为随访主要观察项目。疗效按胸廓出口综合征评定标准评定。结果 术后症状明显改善15例16侧，部分改善6例，无效10例。优良率为68．7％。结论 该组病例远期疗效的优良率为68．7％，因此，胸廓出口综合征的治疗方法仍是个有待于进一步研究的临床课题。     

臂丛神经卡压综合征的诊治

目的探讨位于臂丛神经及其前中斜角肌周围的神经卡压综合征的特点及其诊治方法。方法2003年7月～2006年1月,采用门诊收集病例,根据病情轻重分组,分别采用药物、局部封闭及手术方法治疗179例确诊为臂丛神经和(或)其属支卡压综合征的患者。其中采用药物、手法治疗89例；注射治疗74例,其中需要第二次注射32例；手术治疗16例,同时或分别进行双侧手术2例,需要第二次手术者1例。结果128例患者得到1个月～2年5个月随访。其中,药物手法治疗55例,症状均有不同程度改善或能维持现状。局部注射治疗58例(其中接受第二次注射者24例),2例出现心跳减缓,其余病例无并发症发生,VAS评分情况：1分2例,2分16例,3分20例,4分12例,5分3例,6分3例,7分2例；第二次注射结果：2分5例,3分16例,4分3例。手术治疗15例,其中10例术后症状得到明显改善,恢复工作。结论臂丛神经及其属支涉及其周围众多神经,可产生众多症状；明确病因后,治疗上以保守治疗为主,效果欠佳者采用手术治疗,均可取得较好疗效。     

在内窥镜辅助下手术治疗胸廓出口综合征10例报告

目的 报告并探讨一个治疗胸廓出口综合征(thoracic outlet syndrome，TOS)的新方法，即在内窥镜辅助下进行手术治疗。方法 局部麻醉下在颈外侧作1．5cm长的小切口，在内窥镜的辅助观察下，切断部分前中斜角肌的腱性起始纤维。结果 2092年3月11日至2002年12月16日，共作10例。手术当天10例的症状和体征均完全消失。术后随访4个月～1年，平均6个月。5例的症状和体征完全消失。4例的肌力恢复正常，前臂和小指的刺痛觉稍减退。1例仅偶有颈部不适的症状，术侧锁骨区有麻痛，针刺有痛觉过敏。结论 在内窥镜辅助下经颈部微小切口切断部分前中斜角肌的腱性起始纤维，可解除斜角肌对臂丛神经的压迫，是一个创伤很小的治疗胸廓出口综合征的新方法。     

Upper plexus thoracic outlet syndrome--case report

A 47-year-old right-handed female became aware of proximal ache and muscle weakness in the right shoulder and elbow in 1997. Atrophy of the right biceps muscle was recognized and the right deltoid, triceps, supraspinatus, and infraspinatus muscles were weak. The Morley test and elevated arm stress test were positive. Neurolysis of the brachial plexus and anterior scalenectomy were performed via a right supraclavicular approach. An abnormal fibromuscular band was identified passing between the upper and middle trunks and constricting the middle trunk. Another scalene muscle anomaly was found passing between the C-5 and C-6 nerve roots and connecting the anterior and middle scalene muscles. These muscles were resected, and thorough neurolysis was performed around all nerves and the trunks. Postoperatively, all symptoms completely resolved and the patient was discharged 5 days after surgery. Thoracic outlet syndrome (TOS) manifests as symptoms of lower cervical nerve involvements with hypesthesia and paresthesia. However, upper plexus TOS manifests as symptoms due to the involvement of the C-5 to C-7 nerve roots, and is relatively rare. Transaxillary first rib resection is performed as the primary operation for TOS, but supraclavicular scalenectomy is effective for upper plexus TOS.     

Intraneural steroid injection as a complication in the management of carpal tunnel syndrome. A report of three cases

Steroid injection can provide symptomatic relief in patients with carpal tunnel syndrome (CTS). Its role should be limited to a diagnostic aid in cases in which symptoms are atypical, a temporizing agent in patients with severe symptoms either who are awaiting surgery or in whom spontaneous remission might be expected, and as a definitive treatment in patients who do not desire surgery. Injection should be performed using proper technique by physicians skilled in carpal tunnel surgery. A soluble preparation of dexamethasone is recommended. Immediate paresthesia in the median nerve distribution or exacerbation of symptoms beyond 48 hours following injection is suspect for inadvertent nerve injury; therefore, early surgical decompression is indicated.     

The anterior scalene muscle in thoracic outlet compression syndrome. Histochemical and morphometric studies

Histochemical studies and morphometric fiber type analysis were done on biopsy specimens of anterior scalene muscle (ASM) from patients with thoracic outlet compression syndrome (TOS), without structural abnormality. Hypertrophy and atrophy factors were determined from muscle fiber histograms of ASM from controls, patients with TOS, and after scalene tenotomy. Scalene muscle from patients with TOS showed marked type 1 (tonic contracting) fiber predominance (85.1% +/- 5.1%) and type 1 fiber hypertrophy (55.6 +/- 2.7 microns). After tenotomy there is a reduction of type 1 fiber representation, selective atrophy in the type 1 fiber system (atrophy factor, 0.66 +/- 0.24), and increase of type 2 fibers. These distinctive changes indicate that ASM is uniquely structured in fiber composition to sustain prolonged contraction. The ASM in patients with TOS demonstrates an extraordinary adaptive transformation and recruitment response in the type 1 fiber system reflecting chronic increased tone or motor neuron stimulation. These observations form a basis for clarifying the structural and pathophysiologic changes in TOS.     

Recurrent neurogenic thoracic outlet syndrome

BACKGROUND: Although 90% of patients with neurogenic thoracic outlet syndrome (NTOS) experience "excellent" or "good" results after thoracic outlet decompression, recurrent symptoms may develop in certain patients. METHODS: This is a retrospective review of patients with NTOS who developed recurrent symptoms of upper extremity/shoulder/neck pain, weakness and limitation of motion at least 3 months after initial relief of symptoms by surgical decompression. Diagnostic procedures and outcomes of reoperative surgery were assessed. RESULTS: Among almost 500 patients undergoing initial successful thoracic outlet decompression for symptoms of NTOS during the last decade, 17 redeveloped classic NTOS symptoms (3 of them bilaterally) at intervals from 3 to 80 months (mean 18 months) after the initial operative procedure. Ultimate diagnoses included incomplete first-rib resection (n = 1), compression of the brachial plexus by an ectopic band (n = 1), persistent brachial plexus compression by an intact first (n = 2) or second (n = 1) rib, brachial plexus compression by the pectoralis minor tendon (n = 13) and adherent residual scalene muscle (n = 14). Anterior scalene muscle block was positive in 9 patients later found to have recurrent symptoms from adherent residual scalene muscle. Among these 20 cases of osseous or musculotendinous causes of recurrent NTOS, all had "excellent" or "good" results from repeat surgery to eliminate the underlying structural problem (removal of intact or residual rib, pectoralis minor tenotomy, brachial plexus neurolysis, or a combination of these). CONCLUSIONS: Complete excision of cervical or first ribs and subtotal excision (instead of simple division) of the scalene muscles will decrease the incidence of recurrent NTOS. Pectoralis minor tenotomy should be considered part of complete thoracic outlet decompression. Anterior scalene muscle block accurately predicts outcome of reoperation for certain types of recurrent NTOS.     

Diagnosis of thoracic outlet syndrome

Thoracic outlet syndrome (TOS) is a nonspecific label. When employing it, one should define the type of TOS as arterial TOS, venous TOS, or neurogenic TOS. Each type has different symptoms and physical findings by which the three types can easily be identified. Neurogenic TOS (NTOS) is by far the most common, comprising well over 90% of all TOS patients. Arterial TOS is the least common accounting for no more than 1%. Many patients are erroneously diagnosed as "vascular" TOS, a nonspecific misnomer, whereas they really have NTOS. The Adson Test of noting a radial pulse deficit in provocative positions has been shown to be of no clinical value and should not be relied upon to make the diagnosis of any of the three types. The test is normal in most patients with NTOS and at the same time can be positive in many control volunteers. Arterial TOS is caused by emboli arising from subclavian artery stenosis or aneurysms. Symptoms are those of arterial ischemia and x-rays almost always disclose a cervical rib or anomalous first rib. Venous TOS presents with arm swelling, cyanosis, and pain due to subclavian vein obstruction, with or without thrombosis. Neurogenic TOS is due to brachial plexus compression usually from scarred scalene muscles secondary to neck trauma, whiplash injuries being the most common. Symptoms include extremity paresthesia, pain, and weakness as well as neck pain and occipital headache. Physical exam is most important and includes several provocative maneuvers including neck rotation and head tilting, which elicit symptoms in the contralateral extremity; the upper limb tension test, which is comparable to straight leg raising; and abducting the arms to 90 degrees in external rotation, which usually brings on symptoms within 60 seconds.     

胸廓出口综合征的新认识——解剖学与临床观察

目的探讨胸廓出口综合征的病因。方法对３０具６０侧经福尔马林固定的成人尸体小斜角肌及前中斜角肌的起始部进行解剖研究;对５３例胸廓出口综合征手术患者（１９６６～１９９４年４５例,１９９６～１９９７年８例）随访情况进行总结分析。结果解剖研究发现小斜角肌的出现率为８８３％,Ｔ１神经根或其下干在小斜角肌近段起源的腱性组织上跨过;前中斜角肌在颈椎横突的前后结节均有起点,Ｃ５、Ｃ６神经根从前中斜角肌的交叉腱性起点中穿过。４５例１９６６～１９９６年手术者中,有颈肩痛症状者３４例,术后１７例颈肩痛症状仍存在,其中７例加重;８例１９９６～１９９７年手术者中,７例有颈肩痛,术中切断前中斜角肌在Ｃ５～６神经根旁的腱性纤维组织,术后仅有１例仍有颈肩部不适。结论小斜角肌的腱性纤维是臂丛神经下干或Ｔ１神经根受压的原因;前中斜角肌在Ｃ４～５横突前后结节的交叉腱性起点是压迫Ｃ５～６,有时包括Ｃ７神经根或臂丛神经上（中）干的原因     

Decreased Tear Expression with an Abnormal Schirmer''s Test Following Botulinum Toxin Type A for the Treatment of Lateral Canthal Rhytides

BACKGROUND: Inactivation of muscles of facial expression by chemodenervation with botulinum toxin remains an off-label indication. Nevertheless, it continues to be a safe and effective technique to improve dynamic rhytides and is the treatment of choice for the hypertrophic lateral fibers of the orbicularis oculi muscle that can cause the superimposed crow's feet. OBJECTIVE: Although infrequent and self-limiting, the complication of unexpected muscle weakness from toxin diffusion or erroneous placement is documented. METHODS: However, injection into the pretarsal portion of the orbicularis oculi muscle resulting in unilateral ocular irritation and diminished tear expression as evidenced by a dry eye and an abnormal Schirmer's test has rarely been reported. Direct injection into the pretarsal fibers of the muscle as opposed to diffusion of the toxin into the muscle fibers or the lacrimal gland was consistent with the onset of action of the toxin and the prolonged duration of the ocular symptoms. RESULTS: Treatment consisted of ocular lubrication until the effects of the toxin dissipated and muscle tone returned. Subsequent treatment did not result in a result in a recurrence of adverse sequelae. CONCLUSIONS: Facial muscles are small, not isolated, and often have fibers that interdigitate. An important factor in the administration of botulinum toxin is the identification of the muscles responsible for the corresponding rhytide. Precise knowledge of muscular anatomy and function will aid in minimizing this and other potential complications.     

Variations of the course of the upper trunk of the brachial plexus and their clinical significance for the thoracic outlet syndrome: a study on 93 cadavers

The aim of this study is the recording of the variations of the course of the upper trunk (UT) of the brachial plexus (BP) and their clinical significance for the thoracic outlet syndrome (TOS) and the anesthetic blockade of the BP. Five different anatomical variations of the course of the UT of the BP, in relation to the anterior scalene muscle (ASM), were observed in 24 out of the 186 sides of the 93 cadavers we studied (12.9%). The C5 root was passing anteriorly to the ASM in six cases. The UT was located anteriorly to the ASM in four cases and was perforating the ASM's belly in 12 cases. In one cadaver, the ASM was double and the UT was passing between the two bellies of the double ASM. Finally, in another cadaver, the C5 root was found to be anterior to the anterior scalene muscle, while the C6 root was perforating the ASM's belly. These variations are predisposing factors for the TOS; they cause specific symptomatology and require a different surgical approach in comparison with other causes of the syndrome. Moreover, knowledge of these is important during the performance of the anesthetic blockade of the BP.     

Safety and tolerability of sedation-free flexible cystoscopy for intradetrusor botulinum toxin-A injection

PURPOSE: Intradetrusor botulinum toxin-A injection is a promising emerging therapy for neurogenic and idiopathic overactive bladder that is refractory to current antimuscarinic agents. We evaluated a sedation-free procedure using flexible endoscopy to perform intradetrusor botulinum toxin-A injection using a validated pain score to assess the tolerability of this technique. MATERIALS AND METHODS: Five men and 22 women with idiopathic overactive bladder refractory to antimuscarinics were prospectively evaluated and randomized to 100 U (14) or 150 U botulinum toxin-A (13). Subjects underwent BTA injection with intravesical lidocaine using a 14Fr Olympus flexible cystoscope, which accommodates a 27 gauge flexible Olympus injection needle. Patients were evaluated with the visual analog scale to evaluate discomfort during and 15 minutes after the procedure. Procedure time was recorded. RESULTS: In 22 female patients the mean pain score was 3.1 (range 0 to 10) during the procedure and 0.7 (range 0 to 7) 15 minutes after the procedure. In 5 male patients the mean pain score was 1.6 (range 0 to 3.5) during the procedure and 0.0 with all reporting no pain 15 minutes after the procedure. Mean procedure time was 4.5 minutes (range 4 to 6). Only 1 of the 27 patients requested sedation before any subsequent injections. CONCLUSIONS: Sedation-free intradetrusor botulinum toxin-A injection using intravesical lidocaine and flexible endoscopy is a well tolerated and safe procedure to perform in an office setting.     

Pediatric thoracic outlet syndrome: a disorder with serious vascular complications

Background

Thoracic outlet syndrome (TOS), caused by compression of the neurovascular structures between the clavicle and scalene muscles, typically presents with neurologic symptoms in adults. We reviewed our experience with 25 adolescents and propose a diagnostic/treatment algorithm for pediatric TOS.

Methods

From 1993 to 2005, 25 patients were treated with TOS. A retrospective chart review was performed with institutional review board approval. Demographics, clinical presentation, diagnostic studies, and treatment were evaluated.

Results

Seven male (28%) and 18 female (72%) patients presented between the ages of 12 to 18 years. Thirteen (52%) had vascular TOS (11 venous, 2 arterial), 11 (44%) had neurologic TOS, and 1 had both. Vascular TOS included subclavian vein thrombosis (7), venous impingement (4), and arterial impingement (2). Three patients had hypercoagulable disorders, and 6 had effort thrombosis. Venography was diagnostic in 10 cases. Neurogenic TOS was diagnosed by clinical symptoms. Five patients with subclavian vein thrombosis underwent thrombolysis, with 3 maintaining long-term patency. Of 25 patients, 24 underwent transaxillary first rib resection.

Conclusion

Vascular complications are more common in adolescents with TOS than in adults. A diagnostic/treatment algorithm includes urgent venography and thrombolysis for venous TOS and a workup for hypercoagulability. Neurogenic TOS is diagnosed clinically, whereas other studies are rarely beneficial.     

Dynamic neuromusculoskeletal ultrasound documentation of brachial plexus/thoracic outlet compression during elevated arm stress testing

Background

The diagnosis and validation of thoracic outlet syndrome/brachial plexopathy (TOS) remains a difficult challenge for surgeons, neurologists, and radiologists. This is due to the fact that the responses of standard elevated arm stress tests can be considered somewhat subjective and can vary. Therefore, non-vascular TOS cases are presently diagnosed clinically, and any objective diagnosis has been controversial.

Methods

This is a technique paper describing the use of dynamic neuromusculoskeletal ultrasound to assist in the diagnosis of thoracic outlet/brachial plexus pathology. We propose a new way to observe the brachial plexus dynamically, so that physical verification of nerve compression between the anterior and middle scalene muscles can be clearly made at the onset of clinical symptoms. This gives a way to objectively identify clinically significant brachial plexus compression.

Results

Dynamic testing can add objective analysis to tests such as the elevated arm stress tests and can correlate the onset of symptoms with plexus compression between the anterior and middle scalene muscles. With this, the area of pathologic compression can be identified and viewed while performing the dynamic testing. If compression is seen and the onset of symptoms ensues, this is a positive confirmatory test for the presence of TOS and a clinically significant disease.

Conclusions

This paper offers a simple, objective, and visual diagnostic test that can validate the presence or absence of brachial plexus compression during arm elevation in patients with brachial plexus injury and thoracic outlet syndrome.     

Blood Concentration of Lidocaine during Continuous Epidural Blockade

The blood concentration of lidocaine was studied in 22 patients with continuous epidural blockade, using 0.4 per cent lidocaine (Xylocain®) drip for postoperative pain relief after cholecystectomy. In 12 patients with thoracic blockade, mean infusion dose rate was 3.2 ±0.1 mg/h.kg, and in 10 patients with thoraco-lumbar blockade 4.5±0.3 mg/h.lg body weight. Mean infusion time was 38 hours. A 'steady state' blood concentration of lidocaine of 4–5 μg/ml was not reached until after about 38 hours in both groups. After the end of the infusion the lidocaine, concentration in the blood reached half of the 'steady state' value after 2–3 hours. After about 4 hours the elimination was definitely slower. Signs of central nervous system toxicity were seen at blood concentrations of about 6 μg/ml, which occasionally occurred following superimposed bolus injections of 2 per cent lidocaine.     

Thoracic outlet syndrome: Fact or fancy? A review of 409 consecutive patients who underwent operation

Objectives

From an analysis of patients operated on by a single surgeon between 1973 and 1994 for thoracic outlet syndrome (TOS), to determine what findings are helpful in substantiating this diagnosis and what are the results of decompressive thoracic outlet surgery in the management of TOS.

Design

A chart review with emphasis on signs, symptoms and results. A preoperative questionnaire was presented to all patients operated on since 1989. Postoperative follow-up was by interview or telephone.

Setting

A 560-bed university-affiliated tertiary-care teaching hospital.

Patients

There were 409 adults; 83% were women and the average age was 36 years. In 95% of patients physiotherapy had been unsuccessful. Patients presented with neurologic type (368 [(90%]), arterial impingement (29 [7%]) and venous obstructive symptoms (12 [3%]). The series included 44 patients with bilateral symptoms and 26 patients with cervical ribs. Some form of litigation or compensation was associated with 177 patients.

Interventions

Transaxillary first rib resection in 380 (93%) patients and supraclavicular thoracic outlet decompression in 29 (7%). In 244 patients there was a follow-up of at least 2 years. These patients constituted the follow-up group.

Results

Preoperatively, in the 368 patients who had neurologic TOS, 99% displayed supraclavicular brachial plexus tenderness and 98% exacerbation of symptoms with arms in the abduction external rotated position. There were eight complications of surgical intervention (1.9%). In the follow-up group, there were no deaths, no subclavian/axillary artery or vein damage and no brachial plexus injury. Seventy-eight percent of the patients with neurologic TOS in this group improved postoperatively; 21% had complete relief, 32% had good relief and 25% had fair relief. Twenty-two percent showed no improvement.

Conclusions

Signs and symptoms helpful in making the diagnosis of neurologic TOS are supraclavicular tenderness on palpation and exacerbation of symptoms with the arms in the abducted external rotated position. The surgical procedures are safe. Patients with TOS refractory to medical management can benefit from thoracic outlet decompression.     

Surgical decompression for thoracic outlet syndrome

Fifty consecutive surgical decompression operations for thoracic outlet syndrome (TOS) were performed in 43 patients over a 7-year period. Of these, 54% presented with neurological symptoms alone; the others complained of symptoms of vascular or combined origin. Operations for decompression consisted of excisions of 14 cervical ribs, 22 first ribs, and 14 soft tissue or fibrous bands. In six limbs, cervical sympathectomy was also performed for patients who had secondary Raynaud's phenomenon. Surgery resulted in complete relief of symptoms in 37 limbs (74%) and an improvement was achieved in another 10 (20%). In three limbs (6%) surgery gave no benefit. There was no mortality. Thoracic outlet decompression via the supraclavicular approach gave good results in 94% of the patients.     

A comparison of methods of botulinum toxin injection for abductory spasmodic dysphonia

Treatment of abductory spasmodic dysphonia with botulinum toxin injection into the posterior cricoarytenoid muscles often results in only partial symptom relief. In contrast, excellent results can be achieved after thyroarytenoid injection for the adductory type of spasmodic dysphonia. One reason for disappointing results may be inaccurate placement of the botulinum toxin into the posterior cricoarytenoid muscles. We describe a new approach to posterior cricoarytenoid injection used in 18 patients for treatment of abductory spasmodic dysphonia. Of the 30 patients treated for abductory spasmodic dysphonia at Loyola University–Chicago, 6 underwent both a retrocricoid approach and the newer transcricoid method, thus allowing patient and clinician comparison of techniques. We and all six of our patients preferred the transcricoid approach because of less discomfort, equivalent or better voice results, and fewer side effects. (Otolaryngol Head Neck Surg 1997;117:487-92.)