256 13 Painful Syndromes

Painful Shoulder−Arm Syndromes (SAS)

Pain in the shoulder and arm is a common complaint. The differential diagnosis includes conditions belonging to widely disparate medical specialties: cervical spine pathology (spondylogenic arm pain); degenerative changes of the joints of the shoulder and upper limb and the adjacent connective tissues (ligaments, tendons, joint capsules); diseases of the cervical nerve roots, brachial

plexus, and peripheral nerves (neurogenic arm pain); and vascular diseases. Finally, there remains “arm pain of overuse,” a collection of conditions due to nonphysiological stress on the muscles and joints of the upper limb.

An overview of diseases producing pain in the shoulder and arm is provided in Table 13.10. The clinical features of the more common conditions of this type are described in the following paragraphs.

Table 13.10 Overview of shoulder−arm pain

Category	Etiology	Remarks
Spondylogenic pain	spondylosis	nuchal pain at first; pain radiation is
	disk herniation		often diffuse
			acute torticollis at first, only later fol-
			lowed by pain radiation in a radicular
			pattern; demonstrable neurological
			deficits
Nonspondylogenic nerve root lesion	tumor	slowly progressive symptoms
	dissection of the vertebral a.		acute, unilateral nuchal or occipital
			pain
Brachial plexus lesion	tumor	e. g., lung apex tumor with lower
			brachial plexus involvement and
	radiation injury		Horner syndrome
			pain and progressive neurological defi-
	neuralgic shoulder amyotrophy		cits after a latency period
			intense pain for one or more days, fol-
			lowed by weakness of shoulder girdle
	thoracic outlet syndrome (TOS)		or arm muscles
			overdiagnosed; the diagnosis can be
			accepted if there is a cervical rib or
	hyperabduction syndrome		other anomaly of the thoracic outlet
			the arm “falls asleep” at night in cer-
	posttraumatic brachial plexus dysfunc-		tain positions
			phantom pain, neuroma pain, stump
	tion		pain
Lesion of an individual peripheral nerve	radial n.	supinator syndrome
(or branch)	median n.		pronator syndrome, carpal tunnel syn-
			drome (most common cause of noc-
	ulnar n.		turnal arm pain)
			sulcus ulnaris syndrome
	cutaneous sensory branches		e. g., elbow after paravenous injection
Rheumatologic disorders	in the shoulder region	rotator cuff involvement, impingement
	in the elbow region		syndrome
			radial epicondylitis (tennis elbow),
	in the distal forearm and hand		ulnar epicondylitis (golfer’s elbow)
			radial styloiditis, metacarpophalangeal
			joint of the thumb, e. g., in gout
Brachialgia of vascular origin	arterial	acute brachial a. occlusion, subclavian
	venous		steal syndrome
			effort thrombosis
Tenomyalgic and pseudoradicular overuse	diffuse brachialgia after nonphysiologi-	various professions, e. g., bank teller, or
syndromes	cal overuse of an arm, or secondary to		in the wake of trapezius weakness
	weakness of the shoulder muscles	a locally painful blue spot is often vis-
Rarer causes	glomus tumor

ible under the fingernail; the pain increases when the arm is dependent

Mumenthaler / Mattle, Fundamentals of Neurology © 2006 Thieme All rights reserved. Usage subject to terms and conditions of license.

Painful Shoulder−Arm Syndromes (SAS)

Spondylogenic (Cervicogenic) Shoulder

and Arm Pain

Etiology. The cause is usually degenerative osteochondrosis producing spondylotic narrowing of the intervertebral foramina; sometimes, cervical disk herniation is also present. These disease processes compress and mechanically irritate the cervical nerve roots.

Clinical manifestations. Conditions of this type always begin with neck pain and/or a painful restriction of head movement. Later on, the pain radiates into the shoulder and usually down the arm (cervicobrachialgia). The pain is diffuse in some patients, but often remains mostly within the dermatome of the affected nerve root (i. e., radicular pain): thus, C6 lesions cause pain on the lateral aspect of the forearm and the thumb region, C7 lesions cause pain in the middle finger, and C8 lesions cause pain on the ulnar side of the hand and in the fourth and fifth fingers (cf. p. 208). The objective findings include painful restriction of head movement and, sometimes, radicular neurological deficits—weakness, loss of reflexes, and diminished sensation in the distribution of the affected nerve root (cf. Table 12.1, p. 208).

Treatment. Physical therapy and analgesic medications are the mainstays of treatment (cf. p. 211).

Degenerative and Rheumatic Shoulder

and Arm Pain

Most cases of pain in the shoulder and arm are probably caused by degenerative changes of the bones, joints, tendons, and other soft tissues.

Degenerative disease of the rotator cuff. This painful syndrome, formerly termed humeroscapular periarthropathy, arises after shoulder trauma (a blow or sprain) or immobilization. The tendons of the short rotators of the shoulder joint undergo degenerative changes, sometimes with calcium deposition, and these changes lead to irritation of the subdeltoid bursa. The highly typical clinical finding is local shoulder pain on active raising of the arm, particularly with simultaneous internal rotation. It is painful, for example, for the patient to slip the arm into a sleeve while getting dressed. If the abducted arm is then rested on a surface (table, etc.), the pain disappears. The diseased tendon(s) is (are) tender to palpation, usually ventral to the shoulder joint. Plain radiographs may reveal calcifications. Rotator cuff tear produces mechanical weakness of abduction, objectively demonstrable as the so-called “lag sign.”

Impingement syndrome is closely related to degenerative disease of the rotator cuff. In this condition, when the arm is abducted, the painful area of the rotator cuff comes into contact with the coracoacromial roof.

Frozen shoulder syndrome sometimes represents the end stage of degenerative disease of the rotator cuff, but more commonly arises as a sequela of hemiparesis or

myocardial infarction. It is also rarely caused by phenobarbital use. It is characterized by very painful restriction of shoulder movement, with a slowly progressive course.

Regional pain syndrome. This often-intractable condition used to be known as reflex sympathetic dystrophy, algodystrophy, or Sudeck dystrophy. The sympathetic nervous system plays an important role in its pathogenesis, particularly as a cause of the characteristic swelling. Faulty information processing in the neurons of the dorsal horn of the spinal cord is thought to be another contributing factor. Regional pain syndrome can affect any part of the upper or lower limbs, but it is particularly common in the hand. It tends to arise after a fracture or other type of trauma, which need not be particularly severe. The clinical findings include soft tissue swelling, smooth, cool, often cyanotic skin, and a very painful restriction of joint mobility. Plain radiographs reveal patchy osteoporosis of the bones in the affected area.

Epicondylitis is characterized by pain at the origins of the extensor and flexor muscles of the hand and fingers on the humeral epicondyles. The pain can be felt spontaneously, on movement of the affected tendons and muscles, or in response to local pressure. The usual cause is muscle overuse. The commonest type is lateral epicondylitis, so-called “tennis elbow.” Medial epicondylitis (“golfer’s elbow”) is rarer and is caused by overuse of the flexor muscles.

Styloiditis. Radial styloiditis is characterized by pain at the tendinous origins of the extensor carpi radialis muscles on the styloid process of the radius; ulnar styloiditis is the analogous condition on the styloid process of the ulna. Both of these conditions are varieties of tendinitis, similar to other varieties occurring elsewhere in the body.

Neurogenic Arm Pain

In these conditions, pain in the arm and shoulder is due to a lesion affecting sensory nerve fibers, either in the brachial plexus or in the peripheral nerves. The lesion may be either mechanical (common) or infectious/inflammatory (less common).

Irritation of the Brachial Plexus

Compression of the brachial plexus at the thoracic outlet can occur at any of several anatomical bottlenecks (the scalene hiatus, the costoclavicular passage, or the subacromial space). This generally occurs, however, only when an additional pathogenic factor is present, such as a cervical rib, fibrous band, anomaly of the scalene attachments, or excessive exogenous pressure. The corresponding clinical syndromes are discussed in Chapter 12 (p. 220).

Brachial plexus tumors sometimes cause progressively worsening arm pain that becomes very severe within a matter of weeks. Pancoast tumors of the lung apex are a well-known cause (p. 222).

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Painful Syndromes

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Mumenthaler / Mattle, Fundamentals of Neurology © 2006 Thieme All rights reserved. Usage subject to terms and conditions of license.