Acquired
conditions
The
painful shoulder
After back pain, shoulder pain is the second most common musculoskeletal
problem seen by primary care physicians. The commonest causes of the painful
shoulder in adults are disorders of the rotator cuff, particularly the
supraspinatus tendon. Although conditions such as the painful arc syndrome,
impingement, rotator cuff tears and cuff tear arthritis are often considered as
separate conditions, in reality they
are part of a spectrum of disorders of the supraspinatus tendon. Other
causes of shoulder pain include calcific tendonitis, frozen shoulder and
degenerative disease.
Disorders
of the rotator cuff
In common with some other tendons of the body, the supraspinatus tendon
has a relatively poor blood supply, and this can predispose to both degenerative
changes and tearing of the tendon. The anterolateral portion of the tendon is
initially affected and swelling of this portion may lead to impingement between
the greater tuberosity of the humerus and the anterior acromion with its
attached coraco-acromial (CA) ligament. This leads to pain, particularly on
active abduction or flexion, and initially leads to a painful arc between
60-120degree.
Abnormalities
of the bone occur, with hooking of the anterior acromion. These are probably
secondary changes, rather than the primary cause of the pain, but surgical
treatment is often directed against the acromion and the CA ligament.
History
and examination
The patient is usually middle aged, and the initial symptoms may be due
to a specific traumatic incident or a period of overuse of the arm, or there may
be no precipitating events. The pain is activity related, particularly on
overhead activities, such as reaching up to shelves or hair washing. Gardening
and household activities often produce symptoms. Some patients complain of
significant weakness, and this may indicate the presence of a rotator cuff tear.
On
examination, there is often no local tenderness. Active movements may be
limited, and usually reproduce the symptoms, which occur between 60-120degree of
abduction and flexion (Fig. 22.2). There is usually much less pain on passive
movements, and this confirms the mechanical nature of the pain. Weakness of both
supraspinatus and infraspinatus may be demonstrated, and suggest the possibility
of a tear in the cuff. Specific impingement tests have been described and help
to confirm the diagnosis (Figs 22.3 and 22.4). Radiographs
Subacromial
injection of local anaesthetic and cortisone often leads to improvements in the
symptoms and they are used for both diagnostic and therapeutic purposes. If the
diagnosis is correct, the symptoms are usually improved. The benefit may only be
short lived, but this is a valuable diagnostic aid. Improvement in symptoms
occurs for a few weeks after the injection, but subsequent relapse commonly
occurs.
Further
investigations
A subacromial injection is the most useful diagnostic test, and this is
easily performed in the out-patient clinic. Further investigations such as
ultrasound and magnetic resonance imaging (MRI) are used to determine the
presence of a tear of the rotator cuff if surgery is contemplated; they have
little place in the diagnosis of impingement (Fig. 22.5).
Treatment
It is likely that most patients will settle with conservative treatment.
The initial treatment is by cortisone injection, and this is repeated up to
three times if there is prolonged relief of symptoms. Specific physiotherapy has
a role, particularly in the early stages, but most patients who present to
specialist clinics will only have a limited response. Surgery is eventually
required in 50 per cent of these patients, and is indicated when
symptoms, sufficient to limit activities, have been present for over a year.
Decompression of the rotator cuff is carried out, either arthroscopically, or by
an open procedure, with removal of the anterior overhang and division of the CA
ligament. In addition, repair of a rotator cuff tear may be required. In the
absence of a rotator cuff tear, the prognosis is good.
Rotator
cuff tears
Patients with rotator cuff tears are usually slightly older than
patients with impingement. Tearing of the supraspinatus muscles also starts at
the front lateral edge of the tendon, and can progress posteriorly along the
tendon, detaching it from the greater tuberosity. The tendon retracts medially
leading to a U-shaped tear. The patient is usually unaware of the rotator cuff
tearing, and large tears of several years’ duration may be present before the
patient seeks medical attention (Fig. 22.6).
Small
tears of the supraspinatus
These are very common and may be found in up to 20 per cent of the
normal population, in the absence of any specific shoulder symptoms. The tear is
usually less than 1 cm in length and, in the absence of significant pain, is not
of a sufficient size to cause weakness of the shoulder.
Treatment
of small tears. Treatment is dependent on the presence and severity of
impingement symptoms. In
Intermediate
tears
Tears of 2—3 cm (as measured on ultrasound) are usually associated
with symptoms of impingement or weakness of the shoulder, and these will often
require decompression and repair of the supraspinatus. This can be carried out
through a lateral sabre-type incision. The tendon is mobilised, and then sutured
into a bony trough created on the edge of the greater tuberosity, using osseous
sutures. Results of repair are good for intermediate tears, but full recovery
will take several months.
These are often 5 cm or greater, and may extend into
infraspinatus. They are usually associated with weakness of the shoulder, and
abduction may be limited to 600, often with a characteristic bunching of the
shoulder (Fig. 22.7). With massive tears of the rotator cuff, superior migration
of the humeral head can occur, and this further impairs function. In addition,
secondary osteoarthritis of the glenohumeral head may occur due to the resulting
incongruity of the joint.
Treatment
of large tears. If symptoms of impingement or weakness are sufficient,
decompression and repair should be considered. Unfortunately repair is not
always possible as the medial edge of the tendon retracts, and it may be
impossible to mobilise this to close the defect. Tendon grafts and synthetic
meshes have been used to close this defect but the results are less than
satisfactory. This is due to degeneration and disuse atrophy of the
supraspinatus associated with a chronic tear, and although the gap may have been
closed there is poor function from the repaired tissue.
In
many patients with large tears, the predominant symptom is still pain rather
than weakness and in these patients if the tear is irreparable by direct suture,
simple decompression is carried out. Up to 80 per cent of these patients will
have good relief of symptoms and improved function, despite the unrepaired
rotator cuff tear.
Acute
tears of the rotator cuff
Most tears of the supraspinatus are due to degeneration and, as
discussed above, will be associated with impingement symptoms. Occasionally a
large tear of the rotator cuff can result from trauma, in the absence of any
previous shoulder symptoms. These patients present soon after the event with
profound weakness and loss of function but minimal pain. On examination, there
is marked restriction of abduction, usually to less than 900, with a
characteristic hunching of the shoulder. This is due to elevation and rotation
of the scapula to attempt to aid abduction. Diagnosis is confirmed by ultrasound
or MRI, and early exploration and repair is indicated. Unlike the large
degenerate cuff tears the acute tear
is usually repairable if surgery is carried out early. Often no decompression
is necessary, as the front edge of the acromion is normal with no evidence of
overhang. In middle-aged and elderly patients an acute cuff tear can occur after
shoulder dislocation.
Frozen
shoulder
This is a painful shoulder condition of unknown aetiology that affects
the capsule of the shoulder. The rotator interval between supraspinatus and
subscapularis is affected predominantly. The disease most commonly affects
females in their 50s, and is more common in diabetics and patients with heart or
thyroid disease.
History
and examination
The pain is often of sudden onset and may follow minor trauma. It is
severe and often disturbs sleep, and fractures or joint infection may be
considered in the differential diagnosis. In the early stages, the shoulder is
difficult to examine owing to the pain, but as the disease progresses the range
of motion is reduced, both actively and passively. Local tenderness is often
felt anteriorly over the rotator interval. The pathognomonic sign of frozen
shoulder is loss of external rotation and this differentiates it from rotator
cuff disease. Plain X-rays exclude other intra-articular pathology.
Clinical
course
The clinical course of frozen shoulder can be divided into three stages
as follows.
• Stage I — a painful phase — can last for 2—9
months. The shoulder becomes increasingly painful, especially at night, and the
patient uses the arm less and less. The pain is often very severe, and may be
unrelieved by simple analgesics.
• Stage 2 — a stiffening phase — can last for 4—12 months
and is associated with a gradual reduction in the range of movement of the
shoulder. The pain usually resolves during this period, although there is
commonly still an ache, especially at the extremes of the reduced range of
movement.
• Stage 3 — the thawing phase — lasts for a further 4—12
months and is associated with a gradual improvement in the range of motion.
The
clinical course runs over a period of 1—3 years and usually resolves without
any long-term sequelae.
Treatment
Often no treatment is required and the condition will usually resolve as
described above. The range of motion may be slightly reduced compared with the
unaffected side, but the vast majority of patients has no functional problems.
Treatment
in the acute stage is pain relief. Corticosteroids may be tried but have
variable effects. Active and passive mobilisation can be carried out if comfort
allows but aggressive physiotherapy should be discouraged.
Surgery
is usually reserved for prolonged stiffness affecting function but can also
produce good pain relief in the acute stage. Surgical treatment has a limited
place in management. Manipulation under anaesthetic may produce an increased
range of motion. Arthroscopic distension of the joint with saline allows
inspection of the shoulder before treatment. If these measures fail to produce
any benefit, open release of the rotator interval can be carried out through an
anterior approach.
Calcific
tendonitis
This is a common disorder of unknown aetiology which results in an
acutely painful shoulder. Calcium is deposited within the supraspinatus, and it
is thought that this may be part of a degenerative process. The differential
diagnosis includes frozen shoulder, with both conditions occurring most commonly
in middle-aged women.
History
and examination
This pain is usually of rapid onset, often with no precipitating
cause. In common with impingement, the pain is felt on the anterolateral aspect
of the shoulder and is worse with activities, particularly overhead activities.
The pain can be very severe and usually disturbs sleep. On examination, the
shoulder is tender anterolaterally, and there is often some restriction of
active and commonly passive motion. External rotation will be possible and this
differentiates the condition from frozen shoulder.
The
calcific deposits can be seen on plain radiographs, lying within the
supraspinatus tendon, inferior to the acromion and just medial to the tuberosity
of the humerus. They can also be seen on ultrasound (Fig.
22.8).
Treatment
Simple analgesia should be tried together with physiotherapy, although
specialist referral is commonly indicated. Calcific tendonitis usually responds
to subacromial injection of corticosteroid, although a course of several
injections may be necessary. The condition is often self-limiting with
resolution of the symptoms and resorption of the calcium.
Surgery
Resistant cases of calcific tendonitis are an indication for surgical
treatment. Open excision of the calcific deposits can be carried out through a
sabre incision but arthroscopy of the shoulder with subacromial decompression is
an alternative. The cuff can be debrided and, if the deposits are prominent,
they can be removed through a smaller incision.
The
prognosis for calcific tendonitis is generally good.
Arthritis of the shoulder
Rheumatoid
arthritis
The glenohumeral joint is commonly involved in inflammatory arthritis,
particularly rheumatoid arthritis (RA), with up to one-third of these patients
developing severe problems.
Impingement
symptoms can also occur, either with or without a rotator cuff tear. These will
respond to subacromial injection but decompression may be indicated.
Arthroscopic
synovectomy can be carried out at the same time but, in general, open
synovectomy is not indicated in the management of RA of the shoulder. Chemical
synovectomy may be indicated for symptoms that are resistant to medical
treatment but this is not commonly performed for RA.
For
advanced disease, glenohumeral arthroplasty is indicated, with very good
relief of pain, but there is often little improvement in the preoperative
stiffness.
Osteoarthritis
Osteoarthritis of the glenohumeral joint is either primary or more
commonly secondary. Secondary arthritis is usually due to previous trauma or to
end-stage rotator cuff disease, in association with a massive tear of the cuff
and superior migration of the humeral head.
Treatment.
As with osteoarthritis of other joints, medical measures are initially tried.
Failure of medical management is an indication for surgery. Débridement of the
joint and osteotomy have little if any place in the management of glenohumeral
osteoarthritis, and joint replacement is the treatment of choice. Both total
shoulder replacement and hemiarthroplasty, without glenoid replacement, can be
carried out (Fig. 22.9). Total shoulder replacement should only be carried out
if the rotator cuff is intact. In most patients with RA, and all patients with
cuff tear arthritis, the cuff is deficient and hemiarthroplasty is therefore the
most common replacement performed; this can be carried out through an anterior
deltopectoral approach. Shoulder
replacement is a very good pain-relieving procedure but, in general,
will not restore movement to a stiff shoulder.
Arthritis
of the acromioclavicular (AC) joint
Degenerative changes of the AC joint on plain radiographs are relatively
common and are usually age related. Symptomatic disease, however, usually
affects males in their 20-40s and is commonly due to a previous injury. It is
often seen in individuals who play sport or are involved in an occupation that
stresses the upper limbs. If inferior osteophytes are present, impingement on
the underlying rotator cuff can occur.
History and examination.
The
pain is activity related and, unlike most causes of shoulder pain, it is well
localised, with the patient pointing to the AC joint as the source of the pain.
On examination, there is usually a bony abnormality, with prominence of the
distal end of the clavicle. This may be tender and movement of the joint by
depressing the clavicle whilst pushing up the humerus will reproduce the pain.
Flexing and adducting the arm to place the hand behind the opposite shoulder
will also produce pain. An intra-articular injection of local anaesthetic will
confirm the joint as the site of the pain. If the symptoms are related to the
inferior osteophytes, the pain is less well localised, and impingement signs and
symptoms are present.
Treatment.
Intra-articular injection of corticosteroids will usually produce some benefit
and a course of three injections may be tried. If medical management fails, then
surgery may be appropriate. The distal 1/2 to 1 cm of the clavicle is excised
by a direct approach, with good relief of pain and no functional difficulties.
In patients with predominately impingement symptoms, arthroscopic dehridement of
the osteophytes can be carried out.
Rupture
of the biceps tendon
Rupture of the long head of biceps is a relatively common condition,
occurring in middle age and in the elderly. The condition is closely related to
rotator cuff disease and the tendon usually ruptures owing to chronic attrition.
Although many patients present acutely, an asymptomatic biceps rupture is a
relatively common finding during arthroscopy for rotator cuff surgery.
The patient usually complains of something giving, often when they are
lifting. The arm is often bruised and when the patient flexes the elbow a lump
is evident in the middle of the biceps. The lump is initially tender and power
is diminished (Fig. 22.11).
Treatment
This condition is treated conservatively, and the patient can be
reassured that the pain will ease and the power return, although this may take
several months.
Rupture
of the distal insertion of biceps is an uncommon condition that usually occurs
in younger patients, particularly after a sporting injury. Again pain and
weakness are present hut, unlike rupture of the long head, the weakness will not
improve. Surgical repair is indicated.
Instability
of the glenohumeral joint
Traumatic dislocation of the shoulder will be considered in the next
section but recurrent instability is a common sequele
Classification
There are many ways of classifying shoulder instability, based on
direction, the degree of violence required as well as considering subluxations
and true dislocations. There is a spectrum of instability but, in general, three
groups of patients can be considered as follows (Fig.
22.12).
Recurrent
traumatic instability. This is predominately in one direction, most commonly
anteroinferiorly. There is a definite traumatic event initially, although less
violence is required subsequently. The patient is aware of apprehension on
certain activities and sport may be made difficult. The shoulder may sublux or
dislocate and often the dislocation has to be reduced in a medical facility. On
examination, there is a full painless range of motion but apprehension on forced
abduction and external rotation (Fig. 22.13). Other joints are usually normal.
As discussed in the section on trauma, there is usually a Bankart defect with
detachment of the anteroinferior glenoid labrum and damage to the humeral head (Fig.
22.14).
Treatment.
Conservative treatment has little
place and, if the instability causes functional difficulties, surgery is
indicated. For anterior instability, repair of the Bankart defect, in addition
to some tightening of the capsule, will produce good results in 90—95 per
cent of patients. This is carried out through an anterior deltopectoral approach
(Fig 22.15). For recurrent posterior instability (uncommon) tightening of the
posterior capsule through a posterior approach is carried out.
Atraumatic
instability. Although there may be an initiating event, this is often less
traumatic, for example a fall climbing stairs rather than a sporting injury. In
many cases there is no initial injury and the instability may occur in more than
one direction. The shoulder usually subluxes rather than dislocates and the
patient can often reduce the shoulder themself. The subluxation is painful and
the patient will not dislocate the shoulder at will. On examination, generalised
ligament laxity is commonly present and the shoulder can often be subluxed
inferiorly to produce a sulcus sign, with a lateral sulcus appearing beneath the
acromion as the arm is pulled down. Apprehension tests are again positive but
often in more than one direction.
Approximately
half of the patients will require surgery and a capsular tightening procedure is
carried out through an anterior approach. This is a successful procedure but
there is a higher failure rate than with patients found to have a Bankart
defect. Arthroscopic shrinkage of the capsule may have a place in these
patients, and this is currently being evaluated.
Habitual dislocation.
This
is a much smaller group of patients, but one which does not respond well to
surgical treatment. The patient is able to sublux the shoulder at will and this
is usually not painful (Fig. 22.15). There is underlying joint laxity,
which is usually generalised, and there is rarely a significant traumatic event.
The patient may sublux the shoulder as a ‘party trick’, or for emotional or
psychological reasons.
Treatment.
It
is vital that these patients are assessed and managed by an experienced
therapist. The patient must be educated to avoid subluxing the shoulder and
shown exercises as appropriate. Surgery is associated with a high failure rate
and should be avoided.