Costoclavicular Syndrome

Original Editor - Venus Pagare

Top Contributors - Ilona Malkauskaite, Venus Pagare, Esraa Mohamed Abdullzaher, WikiSysop, Claire Knott, Aminat Abolade, Evan Thomas and Kim Jackson  

Introduction

The costoclavicular passage is one of three passages that consitute the thoracic outlet; the others are the superior thoracic outlet and the costoscalene hiatus. The costo-clavicular passage is formed by the clavicle antero-laterally, the first rib medially, and the scapula posteriorly. The brachial nerve plexus, subclavian artery and subclavian vein run within the costoclavicular space between the first rib and the clavicle.
The neurovascular bundle is vulnerable to compression in this space.

Mechanism

The costoclavicular syndrome was first described in soldiers with loaded knapsacks, who developed pain, numbness, and fatigueability of the arms as they stood at attention. The mechanisms of compression involved downward movement of the clavicle against the first rib, with a resultant tendency to shearing of the neurovascular bundle.

This can occur in three ways:

• The clavicle depresses toward/against the first rib. This can be observed in the common postural condition of rounding and slumping of the shoulders. This narrows the costoclavicular passage by pushing the scapula forwards.
• A tight subclavius can also cause this to occur. A similar mechanism operates in usually obese, middle aged or elderly women. Tight, narrow brassiere straps supporting heavy breasts cut into the soft tissues around the shoulders and exert direct downward pressure on the clavicles, usually around the junction of the mid and lateral thirds. A scissoring action of the clavicle against the first rib narrows the costoclavicular passage and shears the neurovascular bundle.
• The first rib elevates toward/against the clavicle. This often occurs in clients who have laboured breathing. Tight anterior and middle scalenes and subclavius can also cause this to occur.
• The clavicle depresses and the first rib elevates.

Presenting Complaints

• Pain or ache sometimes accompanied by stiffness in the neck and shoulders, pain, paraesthesiae, and fatigueability of the upper limbs are the main presenting complaints.
  
•  Symptoms are usually bi-lateral, though more pronounced on the dominant side.
• They are aggravated by work and exercise, particularly carrying heavy shopping bags.
• Symptoms are relieved by rest and sleep, are minimal or absent in the morning, and become pronounced as the day progresses.
• Patients occasionally complain of puffy blue hands.

Examination

• The most important clues to diagnosis are the deep grooves on both shoulders where tight, narrow bra straps have cut deeply into the underlying soft tissues.
• Direct downward pressure with a forefinger in the groove reproduces symptoms.
• Invariably, there is tenderness over the acromioclavicular joint. Movements of the neck and shoulder are free. The former are painless, but shoulder movements may be slightly painful because of osteoarthritis of the acromioclavicular joint.
• There is no muscle wasting or weakness.
• Paraesthesiae when present are likely to involve the thumb and all fingers and sometimes the whole limb. They differ from the paraesthesiae of carpal tunnel compression in their distribution and timing. Phalen's and Tinel's signs are absent.
• Some patients complain of puffy blue hands. They lack the classic colour changes of Raynaud's phenomenon and are unaffected by cold. The normal appearance of the hand in the costoclavicular syndrome helps to differentiate it from the shoulder-hand syndrome, where it is shiny, swollen, warm, and hyperaesthetic.
• Costoclavicular / Military Brace / Eden's Test is positive