Disorders of the inert structures

Pain on active and passive elevation (Fig. 1)

Fig 1 Shoulder girdle lesions with clavipectoral pain.

Disorders of the sternoclavicular joint

Disorders of this joint are usually the result of an injury; arthrosis, hyperostosis and rheumatoid or septic arthritis are other possibilities.¹ All conditions give rise to both scapular and shoulder signs and occasionally to signs on movements of the neck. The clinical pattern closely resembles that of an acromioclavicular joint lesion but the localization of pain at the medial end of the clavicle draws attention to the sternoclavicular joint. In posterior sternoclavicular syndrome, the pain is felt posteriorly at the base of the neck.

Positive signs are commonly found at three levels: neck or upper thorax, shoulder girdle and shoulder.

Technique: injection of the sternoclavicular joint

The patient lies supine. The gap between the medial end of the clavicle and the sternum is palpated. A needle of 2.5 cm is introduced, penetrating the joint to a depth of about 1 cm (Fig. 3), and 1 ml of triamcinolone acetonide is injected. If excessive resistance is encountered, the needle is in the meniscus; if this occurs, the tip of the needle should be partly withdrawn with continuous pressure on the plunger until the steroid floats in with little resistance.

Fig 3 Injection of the sternoclavicular joint.

Posterior sternoclavicular syndrome

This rare disorder may arise spontaneously in middle-aged people and usually causes a misleading clinical picture.

Patients complain of unilateral pain at the base of the neck. Surprisingly, the pain is felt more posteriorly and not at the sternoclavicular joint itself, which suggests a lesion of the cervical spine. Nevertheless, clinical examination of the neck does not localize the problem: there is usually full range on passive movements and no pain on active and resisted movements. Both active and passive elevation of the arm is painful. Sometimes it is even hard to achieve full range. All other movements of the arm are normal, except for passive horizontal adduction which is most painful. Clinical examination of the shoulder girdle is required. Pain is elicited by active and passive elevation of the shoulder. Resisted shoulder elevation is negative, which excludes the trapezius and levator scapulae muscles. No pain is found on palpation of the anterior portion of the sternoclavicular joint.

Treatment

One or two infiltrations of 20 mg triamcinolone into the posterior sternoclavicular ligament is helpful and can be done in one of two ways:

• By approaching the ligament from above and allowing the needle to progress behind the joint until ligamentous resistance is felt

• From the front, passing through the joint as for an intra-articular injection.

In both instances, the steroid must be infiltrated into the posterior ligament and counterpressure must be present during the whole procedure. Therefore the tip of the needle is partly withdrawn and reinserted several times, over the whole of the posterior ligament, as the product is injected. Throughout, special care must be taken not to penetrate neighbouring visceral structures.

The patient is reassessed after 2 weeks; if symptoms are still present a second infiltration is given. Normally two or three infiltrations suffice.

Arthrosis

Arthrosis of the sternoclavicular joint is common.² It occurs mainly in postmenopausal women. The chief complaint is cosmetic: there is a visible thickening of the joint. The pain, if any, is minor ³. Elevation of the arm is limited as the result of the limitation of the shoulder girdle movement. Movements of the shoulder girdle are uncomfortable but not really painful.

Radiography shows degenerative changes (osteophytes, bone cysts, hyperostosis and diminution of the joint line), most pronounced at the inferior aspect of the clavicular head. Occasionally calcification is seen in the ligaments.⁴

For the overuse phenomenon in arthrosis an intra-articular injection of triamcinolone acetonide can be given.

Rheumatoid arthritis

Rheumatic conditions may also affect the sternoclavicular joint. This often occurs in ankylosing spondylitis.⁵ It gives rise to the same clinical pattern as in a sprain, but local swelling from synovial thickening is present. A progressive ankylosis develops with pronounced limitation of movement in the shoulder girdle. Other sites of rheumatoid arthritis should bring the disorder in mind, although the sternoclavicular joint may be the first joint affected.

Treatment

Local infiltration of triamcinolone acetonide may be helpful.

Septic arthritis

Bacterial agents such as Staphylococcus aureus, Streptococcus group B and Brucella spp. have been isolated in septic arthritis of the sternoclavicular joint.6,7 Septic arthritis occurs in elderly patients with a deficient immune system, with rheumatoid arthritis and diabetes mellitus, and in drug addicts.^8–10 The patient usually has fever, chills and sweating, and complains of pain and swelling in the sternoclavicular area, sometimes at the base of the neck. In about 20% a local, warm and erythematous mass is present at the joint because of abscess formation.^11–13

A combination of neck signs, shoulder signs and shoulder girdle signs is found on examination: