Thoracic inlet syndrome and cervical rib

Thoracic inlet syndrome and cervical rib By Kushal Hippalgaonkar

THORACIC INLET SYNDROMEINTRODUCTIONIt is the compression of subclavian and axillary vessels and trunks of brachial plexus as they pass from the neck to the arm

CAUSES1. DYNAMIC FACTORS Arm in hyperabduction

Axillary artery bent at 180 degrees , pulling it across the coracoid

Compression of axillary artery 2. STATIC FACTORS Increased muscle bulk

Less space compression B) Inactive middle aged adults(decreased bulk)

sagging shoulders

angulation and compression of structures 3.CONGENITAL FACTORS - Cervical rib

4. ATHEROSCLEROTIC FACTORSUnusual vigorous activity in such people

Further narrowing of structures

5.TRAUMATIC FACTORS -fracture clavicle

6. MISCELLANEOUS FACTORSTumours of upper lobe Cervicothoracic scoliosis Anatomical variations in scalene muscle insertion CLINICAL PICTURE

NEUROLOGIC VASCULAR NEUROLOGIC SYMTOMS Lower part of brachial plexus affected mostbecause it overlies the first rib Therefore sensory impairment of C8 and T1

Medial aspect of the arm , forearm and hand .

Numbness , tingling and pain (intermittent and burning)Objective signs of neuro deficit are uncommon

VASCULAR SYMPTOMS

-Coldness of fingers -intolerance to cold -pallor and cyanosis of fingers -raynauds phenomenon in 1/4th patients Impaired blood flow may not be evident unless some maneuvers are performed , which will worsen the flow and cause temporary pallor . They are :

1. Intermittent claudication test : both arms are elevated in abducted and externally rotated position Fingers are flexed rapidly Normally 1 minute ( pt can do this )Thoracic inlet syndrome within seconds (arm collapses

2. Costoclavicular manueverPatient sits with hands on thighAsked to throw shoulders downwards and backwards Radial pulse is felt and supra and infraclavicular regions are auscultated .Positve test absence of pulse + bruit on auscultation COMPLICATIONS Post stenotic dilation of vessel Thrombus formation in this area Embolus to distal vessels Sometimes ulceration and gangrene

INVESTIGATIONS 1. X-ray cervical rib , malunited fracture clavicle , anuerysmal shadow , 2. Arteriography stenosis , aneurysmal dilation , emboli3. Nerve conduction studies slowing of conduction in affected nerve . TREATMENT 1. CONSERVATIVE Effective in majority . Avoid injurious positions during working or sleeping which aggravate the condition Postural positions avoiding the shoulders to droop downTherapeutic exercises 2. SURGICAL Small percentage cases decompression Principle remove 1st thoracic rib and if present , the cervical rib and arterial reconstruction Three approaches : Posterior approachTransaxillary approach Anterior approach

Cervical rib INTRODUCTION

It is a supernumerary rib that usually arises from the 7th cervical vertebra . Frequently bilateral .

DEVELOPMENTAL ANATOMY In the embryo , nerves are much larger in proportion to ribs than in adults . Larger the nerve , more is the interference with development of costal process .

2 types of brachial plexus :

1. prefixed well developed 4th cervical root and poorly developed 1st thoracic root . Therefore , a costal recess develops from this 1st thoracic root . This is the cervical rib Extends from transverse process of 7th rib , varying in size from rudimentary to complete ( extending upto sternum).When rib is underdeveloped , a fibrous band extends from rib to end on scalene tubercle on 1st thoracic rib .

2. postfixed well developed 1st thoracic and poorly developed 4th cervical root . Therefore no cervical rib formation PATHOLOGICAL ANATOMY Due to presence of complete cervical rib or fibrous band

Brachial plexus and subclavian vessels must pass over a higher barrier before passing down into arm

So compression of these structures ( especially lower trunk of plexus (ulnar nerve affection))CLINICAL PICTURE AND INVESTIGATIOONSSimilar to thoracic inlet syndrome features( already discussed)Special findings are :On palpation , bony prominence of cervical rib felt at base of neck ON XRAY , cervical rib seen extending from 7th cervical vertebra transverse process .

TREATMENTCONSERVATIVE For mild symptoms exercises to increase the tone of trapezius and levator scapulae . Arm rested in elevated state to relieve compression

SURGICAL When symptoms are severe , the rib is resected . THANK YOU .