Tanya M. Smith PT, ScD1,2, Valerie Phelps PT, ScD 1,2 and Jean-Michel Brismée PT, ScD 2,3 1 Advanced Physical Therapy Alaska, Anchorage, AK. 2 International Academy of Orthopedic Medicine-US, Tucson, AZ. 3 Texas Tech University Health Sciences Center, Center for Rehabilitation Research, Lubbock, TX. Address correspondence to Tanya M. Smith, 1917 Abbott Road, Anchorage, AK 99507. E-mail: tsmith@aptak.com

Outcomes: On final examination, Cyriax release test and the cervical rotation lateral flexion test were negative, while sensation and motor testing were normalized. The DASH score was 2.0 and sports/performance 0.0. Improvements were maintained at three months follow up.

Discussion: This is the first case study in orthopedic literature to report successful management of true neurogenic TOS in an adolescent musician with axonal conduction loss and the presence of CR.
“Level of Evidence”: Therapy, level 4C

BACKGROUND

Thoracic outlet syndrome (TOS) is characterized mainly by pain and paresthesia into the upper extremities with arm elevation. 23 It is classified into two distinctive categories: vascular and neurogenic. Vascular TOS is further subdivided into arterial and venous, whereas neurogenic TOS is characterized as true neurological or symptomatic. 7,8,23 While the majority of cases in adults are symptomatic TOS without objective findings of axonal conduction loss, adolescents can present more frequently with unequivocal signs and symptoms of vascular changes and/or axonal conduction loss. 5 Repetitive upper extremity use in musicians is associated with the development of neurogenic and vascular TOS, 4,24 which can lead to loss of shoulder girdle stability and hypertrophy or imbalance of the anterior/middle scalene or pectoralis minor muscles or both. The reported incidence of entrapment neuropathy in musicians is 4% to 48%. 19,24 The most common entrapment neuropathies in musicians include carpal tunnel syndrome, ulnar neuropathy at the elbow and TOS. 24 Fifty percent of musicians diagnosed with TOS present with drooped shoulder configuration. 24

One of the consistent findings of neurogenic TOS is scapular depression, which can lead to traction and/or compression of the neurovascular structures at the posterior scalene triangle, costoclavicular space and thoraco-coraco-pectoral space. 7,8 Aberrant scapular position includes depression, downward rotation and winging. Patients presenting with drooped shoulders and neurogenic TOS tend to demonstrate late and insufficient upward rotation of the scapula during elevation in abduction. Similar dysfunction can be seen in flexion; scapular winging, however, can be more prominent in flexion. In addition, increased scapular anterior tilt may be coupled with increased downward rotation of the scapula, which is seen more frequently in abduction.23 These positions can be influenced by an alteration of recruitment, intensity and/or force of the scapular musculature.23 TOS signs and symptoms may begin to manifest secondary to congenital abnormalities predominantly in the adolescent age group.3,5 A cervical rib (CR) can predispose an individual to TOS because of tension/compression and/or irritation to the brachial plexus and/or subclavian vessels.12,20,23 A CR is described as a rudimentary rib, which arises from the transverse process of C7 and has a free end into the soft tissue or articulates with the first rib posterior to the scalene tubercle. The incidence of CR in adults is 0.05% to 3%.3

Symptoms from CR are poorly described in children; a large retrospective study on children from birth to 18 years over a 10-year period was performed to identify the presence of CR in symptomatic and asymptomatic populations. The diagnosis of CR was made incidentally in 88.2% of cases with 11.2% cases having TOS symptoms.3,12 Common presentation of symptomatic CR include: non-inflammatory neck mass (50%), neck pain (41.7%) and rarely upper extremity paresthesia and pain.3 When TOS is suspected and CR is confirmed, the age group tends to be significantly older (16 years) versus a non-TOS group (11 years). Although the association of CR and TOS in adolescents is a rare occurrence, the prognosis is much better when identified and treated in this age group.3,5

This case report presents the examination, interpretation of findings and successful multimodal treatment of an adolescent musician with true neurogenic TOS with presence of bilateral CRs, interventions used during the rehabilitation process and the outcomes of the treatment.

CASE DESCRIPTION

A right hand dominant 16 year-old male student French horn player was referred to physical therapy for evaluation and treatment for complaints of a two-year history of right shoulder pain and upper extremity paresthesia, pain and weakness. The patient was initially evaluated in a military hospital with complaints of insidious onset of shoulder pain; at that time shoulder X-ray imaging was performed without significant findings. Symptoms persisted and became significantly worse four months later following marching band season worsening with writing at school and playing the French horn. By the time the patient initiated physical therapy (at 6 months after his first medical consult) he was reporting constant right shoulder/arm pain and paresthesia with limited function in carrying, grasping, lifting, pulling or reaching. Pain was experienced in the right costoclavicular space, anterior shoulder, medial elbow, medial forearm and the ring and little fingers. The patient complained of occasional right neck pain and tightness. On initial examination he reported constant pain rated 5/10 at best and 7-8/10 at worst. The quality of pain was described as constant aching, occasional sharp pain into the right shoulder, right-sided neck stiffness, burning into the right medial elbow and tingling into the ulnar aspect of the forearm and ring to little fingers of the right hand. The Disabilities of the Arm, Shoulder and Hand (DASH) score was 53.6 and performance sport/music was 75 (scores range from 0 to 100, higher scores indicate increased disability).

Clinical Examination
Findings of the initial clinical examination are reported in Table 1. Only the positive tests are listed. 4
Cervical Spine Active Range of Motion
Cervical flexion No limitation; moderate pain right shoulder/arm
Cervical extension No limitation; moderate pain right shoulder/arm
Cervical right rotation 5 degree limitation; severe pain right shoulder/arm
Cervical left rotation No limitation; mild pain right shoulder/arm
Cervical right sidebending No limitation; mild pain right shoulder/arm
Cervical left sidebending 5 degree limitation; mild pain right shoulder/arm with tingling digits 4 & 5

Upper Extremity Resisted Testing
3/5 fifth digit abduction test right

Sensory Testing
C5, C8 diminished light touch right

Thoracic Outlet Testing
Elevated Arm Stress Test: positive for pain/paresthesia ulnar nerve distribution right
Cyriax release test: positive for pain/paresthesia ulnar nerve distribution right

Mobility Testing Acromioclavicular, Sternoclavicular, Glenohumeral Joints
Acromioclavicular joint: restricted right
Sternoclavicular joint: restricted right
Glenohumeral joint: positive relocation test provoking familiar shoulder pain, mild anterior translation laxity right

Mobility Testing First Rib
Cervical Rotation Lateral Flexion test: restricted bilateral
First rib spring test: hard end feel with reproduction of familiar symptoms right

Scapulothoracic Stability Testing
Winging, tipping in static and dynamic testing right

Neural Tension Testing
Median nerve: positive for symptom reproduction right
Ulnar nerve: positive for symptom reproduction right

Wrist Testing
Ballottement test: positive for hypermobility right
Grip strength Right: 81pounds with 5/10 pain dorsal ulnar aspect of the wrist
Resisted wrist flexion Right: 5/5 and mildly painful ulnar wrist
Resisted wrist flexion with ulnar deviation Right: 5/5 and moderately painful in the ulnar wrist

Ulnar Neuropathy Triad Testing
Elbow flexion pressure provocation test: provoked moderate pain in the ulnar forearm and wrist right
Semmes Weinstein Monofilament testing 2.83 g/f: normal sensory threshold C4-T1 dermatomes bilateral
Fifth digit abduction resisted testing: 3/5 mild pain in ulnar wrist right

Interpretation of Clinical Examination

Findings and Diagnosis

Based on the clinical examination findings, this patient presented with signs and symptoms consistent with true neurogenic TOS and double crush phenomenon involving the ulnar nerve at the right elbow with sensory and motor deficits. He displayed dysfunctions in the upper extremity kinetic chain known to be associated with TOS, such as scapulothoracic instability, sternoclavicular hypomobility and glenohumeral instability.7,8 Additionally, imaging revealed rudimentary CRs and nerve conduction velocity testing of the ulnar and median nerves was positive for prolonged distal onset latency sensory at the wrist.

Prognosis and Plan of Care

The prognosis was favorable; the patient was a young healthy adolescent with optimal family support and motivation to return to his musical interest and daily life without pain. Because he had true neurological deficits in both the median and ulnar nerves on the right side and bilateral cervical rudimentary ribs, surgery could not be ruled out should motor and sensory dysfunctions persist. The primary goals for this patient were to resume 5unlimited French horn playing and to be able to handwrite his school-work without pain or paresthesia.

Interventions

The patient was initially treated twice per week for three months, then one time per week for three months, and finally one time per month for six months. At first, treatment focused on normalizing rib and shoulder mobility that included techniques of right sternoclavicular joint traction manipulation,8posterior and inferior glenohumeral joint glides in prepositioned flexion, posterior capsule mobilization in prepositioned extension and internal rotation,8and soft tissue mobilization to the upper trapezius, middle trapezius, pectoralis major and minor, anterior and middle scalenes and the thoracic paravertebral musculature. This was performed in order to open space at the gates of the thoracic outlet and restore increased blood flow to the vasa nervorum.21 Simultaneous sympathetic nervous system treatment was performed by means of soft tissue mobilization to thoracic paravertebral musculature, normalizing mobility of ribs 1 to 9 bilaterally, and giving the patient a transcutaneous electric nerve stimulation (TENS) unit for a home program (to be applied for several hours daily along the paraspinal muscles at T2 to T9).11 Focus on the sympathetic nervous system was performed to reduce vasomotor constriction of the vasa nervorum to the brachial plexus and upper extremity peripheral nerves. Gentle non-symptom provoking ulnar nerve mobilization was also initiated in the home program. Nerve mobilization was performed without tension or reproduction of familiar pain in order to prevent venous stasis and tethering of the nerve to its sheath.16

Neural mobilization position involved neutral abduction, 20° elbow flexion, neutral forearm position, and wrist extension with simultaneous finger flexion alternating to wrist flexion with finger extension. At the same time, management focused on improving posture and optimizing positioning of the upper extremity during activities of daily living. The patient was fitted for a posture shirt to wear during band practice and school work. (Figure 2) The postural shirt allowed feedback for scapular positioning into relative neutral while preventing thoracic kyphosis and forward head positioning. To begin with, the amount of French horn practice time was limited specifically to thirty-minute increments, four times per week. Elbow flexion was restricted to 20° and forearm rotation to neutral by placing a strip of kinesiotape on the posterior aspect of the elbow. The patient was instructed to avoid sleeping, writing or performing any activity in greater than 20° elbow flexion.

Pain and positive ballottement testing at the distal radial ulnar joint (DRUJ) indicated a fibrocartilaginous complex lesion and DRUJ instability, respectively.22 Subluxation of the distal radial ulnar joint can be caused by hyperpronation or repetitive pronation movements resulting in marked loss of strength in the wrist and hand; thus the patient was instructed to also avoid reaching or grasping with a pronated forearm.9 He was fitted with a WRIST-Widget® brace and instructed to wear it during all right upper extremity activities. Transverse friction was performed to the locally tender right flexor carpi radialis and long finger flexor training was initiated in neutral rotation of forearm to further stabilize the carpus. As the patient’s symptoms of pain and paresthesia diminished, treatment progressed to include scapular neuromuscular re-education. Training focused on centralizing the humeral head prior to elevating the right arm. Additionally, maintaining a relative neutral scapular position with early upward scapular elevation was emphasized during flexion and abduction elevation. As ulnar nerve paresthesia and pain dissipated, medial glide of the humeroulnar joint was performed in order to lengthen the retinacular fibers at the cubital tunnel, thereby promoting increased space in this narrow passageway.1

OUTCOMES

Treatment took place over a total of twelve-months’ time; this duration was needed in order to address the various contributing components of limitation of joint mobility, joint laxity, weakness, and sensory loss. Furthermore, time is required for neurogenic pain disorders to improve once the compressive/tension or injury to the nerve has been alleviated. In cases of neuropraxia where there is temporary axonal conduction loss with demyelination of sensory and motor fibers, minimum healing time is twelve weeks once compressive/tension event on the nerve had stopped.15,18 In this case, once the postural component was corrected, combined with sympathetic dampening activities, the right wrist instability became a more prominent feature and continued to contribute to the multiple crush phenomenon in the right upper extremity (TOS, ulnar neuropathy at the elbow and median neuropathy at the wrist). TOS symptoms were most likely due to narrowing of the costoclavicular space with compression primarily affecting the C8/T1 nerve roots, elbow symptoms were due to ulnar nerve compression in the cubital tunnel, and the wrist DRUJ instability with volar subluxation of the ulna reduced both ulnar tunnel and carpal tunnel volume leading to ulnar and median nerve compromise, respectively.13 On final clinical examination, the Cyriax release maneuver 2 and the elevated arm stress test, 17for symptom provocation in TOS, were negative for right upper extremity pain. Cervical rotation lateral flexion testing for hypomobility of the first rib was no longer symptom 6

Flexion pressure provocation testing was negative for the ulnar nerve at the right elbow, and sensation was normal to light touch in the ulnar distribution of the forearm and hand. Ulnar nerve tension testing was negative for provocation of symptoms on the right side. The ballottement test remained positive for laxity of the right DRUJ. Grip strength improved from 81 pounds and 5/10 pain (tested in a position of elbow extension and forearm pronation) to 105 pounds and 0/10 pain with application of the Wrist Widget®. The patient was encouraged to continue to wear a wrist stabilizing device until he was able to grip without pain. Motor function at C8/T1 fifth digit abduction was normalized 5/5 strength. DASH scores were 2.0 for disability and 0.0 for sports/performance. Follow up was performed at three months after physical therapy cessation. The patient reported experiencing only transient recurrence of right hand paresthesia in the ulnar nerve distribution with prolonged elbow flexion positioning, which abated within one hour after performing his home exercise program of neural mobilization. Improvements in DASH scores for disability and sports/performance remained unchanged. The patient was able to achieve his goals of playing the French horn and writing school-work without limitation or pain.

DISCUSSION:

True neurogenic TOS is uncommon in all age groups with the adolescent age group being most rare.12 Although true neurogenic TOS in adolescents is less frequent than in adults, signs and symptoms are typically unequivocal and are accompanied by axonal conduction loss.5

This is the first case study to report on successful management of true axonal conduction loss of an adolescent musician with TOS and CR. Although the cervical rotation lateral flexion test is not a test designed to evaluate TOS, an elevated first rib is thirteen times more likely to occur in the upper limb of subjects with ulnar neuropathy and/or double crush syndrome.20 Literature has emphasized the association of CTS with impairment of the ulnar sensory nerve fibers at the wrist with prolonged fifth digit sensory latency and increased vibration threshold at the fifth digit.6 There is a strong correlation between CTS and damage to the ulnar sensory fibers at the wrist.6 In addition, subtle volar dislocation of the ulna at the distal radial ulnar joint can reduce the carpal tunnel volume, contributing to signs and symptoms of median and ulnar neuropathies at the wrist.10,14 Subtle volar ulnar subluxations are frequently unrecognized by radiographs, which can lead to long-term pain and disability at the wrist and hand.10,14

Nerve conduction velocity testing of this subject confirmed prolonged distal onset latency of the median and ulnar sensory fibers at the wrist. At no point in the physical therapy intervention did this patient report any pain, paresthesia and/or weakness in the median nerve distribution of the affected arm. Surgical carpal tunnel release had been recommended after the positive findings with electrodiagnostic testing of the median nerve. Nerve conduction velocity testing was not concordant with clinical testing, however, in which pain, paresthesia and weakness were present only in the ulnar nerve distribution of the right upper extremity. Ulnar neuropathy can occur in instances of DRUJ instability with intermittent symptoms related to rotation of the forearm. 10,14The treatment of choice is to stabilize the DRUJ with bracing and strengthening and/or surgical stabilization.9,14

This patient did not undergo surgical carpal tunnel release as symptoms were clearly the result of DRUJ laxity and ulnar neuropathy, and resolved with treatment that specifically addressed those pathologies. 7

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