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C. Dumontier
Hôpital St-Antoine, 184 rue du faubourg St-Antoine, F-75012 Paris
Institut de la Main, 6 square Jouvenet, F-75016 Paris
| WORKUP OF THE RHEUMATOID ELBOW |
Rheumatoid arthritis (RA) frequently affects the elbow; however, it is the presenting complaint in only 3% of cases(15). The clinical and radiological course of the disease is very similar to the pattern seen in the shoulder and the metatarso-phalangeal joints(15). Usually, the symptoms occur late in the course of the disease, after a duration of 11 to 15 years(15, 52). In Hämäläinen’s study(150, only 33% of the elbows were causing symptoms after 17 years of disease, and only 20% had major radiological compromise. On the other hand, in Porter’s earlier series of 225 patients(46), only 28% of the patients had no clinical evidence of elbow involvement; 25% had severe disability in one or both limbs resulting wholly or partly from disease of the elbow. In another study, reported in(52), only 21% of 191 RA patients had unilateral disease.
RA of the elbow presents four different patterns:
1. Nodules and bursitis, which are very common superficial lesions that rarely require treatment.2. Synovial hyperplasia, which marks a more advanced stage of the disease, but is rarely noticed by the patients themselves. The condition is detected by palpation, especially of the lateral aspect of the elbow. This hyperplasia may be so exuberant as to cause synovial herniation, usually in the ulnar groove, with possible nerve compression by the herniated tissue.
3. Ulnar nerve compression, which is due either to synovial proliferation or to joint destruction (Fig. 30). Ulnar nerve translocation is indicated if there is entrapment neuropathy. Compression of the posterior interosseous nerve by synovial cysts arising from the anterior aspect of the humeroradial joint has been reported in RA(25, 27). While this is a rare lesion, the possibility of this entrapment neuropathy should be considered in patients presenting with loss of active extension of the metacarpo-phalangeal (MCP) joints of the triphalangeal digits. The two differential diagnoses to be considered are rupture of the extensors, and irreducible extensor dislocation into the intermetacarpal valley. Often, several features will need to be taken into account. Thus, long-standing and/or severe RA of the elbow, gradual loss of extension, tenderness on palpation of the ulnar groove, and a tenodesis effect on the extensor tendons with wrist flexion, would argue in favour of compression neuropathy. Extension at the interphalangeal joints will still be possible, through the action of the intrinsic muscles of the hand. Wrist extension can still be accomplished, albeit with radial deviation, since only the extensor carpi ulnaris muscle is paralyzed. With incomplete involvement, there will be lack of MCP extension in the fourth and fifth digits only, producing a ‘false ulnar claw hand’, which differs from a true ulnar claw by the absence of MCP joint hyperextension.
4. The chief problem in the management of RA of the elbow is the gradual destruction of ligamentous and/or articular structures by the disease. The workup of the RA elbow will, therefore, have to include an assessment of the stability of the joint in the coronal and the sagittal plane, and an evaluation of the functional capabilities of the elbow and of the other joints of the upper limb (Fig. 26). Patients who cannot ambulate without aids should not be considered for elbow joint replacement.
| CLINICAL WORKUP OF
LATERAL EPICONDYLITIS (TENNIS ELBOW) |
In 1873, Runge first described this condition, noting that “its aetiology is varied, its pathogenesis unknown, and its treatment uncertain.” Since then, much has been written about what is now popularly known as tennis elbow. Readers interested in more detailed information on the subject should consult the extensive literature survey given by Narakas and Bonnard(36).
The disorder has a nearly equal gender incidence, and is most frequently seen in the 35-55 age group(38). Often, a history of elbow overuse can be obtained (change of tools or equipment, different rate of elbow use, etc.). The clinical examination must, in the first instance, establish the actual site of the pain (anterior or posterior aspect of the epicondyle; humeroradial joint; annular ligament; common extensor origin). The radial nerve should be palpated along its course, especially where it passes in front of the annular ligament(36). The muscles are pinched laterally, while the nerve is felt by direct palpation(36).
Lateral epicondylar pain may be caused by humeroradial joint disorders, radial nerve compression, or lesions of the tendinous attachments on the epicondyle. The clinical examination should establish which of these causes is responsible for the symptoms in the particular patient (Table 3).
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"Tendinous" epicondylitis |
Epicondylar pain from nerve damage |
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Pain |
Over the epicondyle |
Yes |
Diffuse |
|
Over lateral elbow |
+++ |
+++ |
|
|
Nocturnal |
(+) |
+++ |
|
|
Exercise-related |
+++ |
+++ |
|
|
Dorsum of wrist |
rare |
frequent |
|
|
Lat. aspect of arm |
rare |
frequent |
|
|
Shoulder |
rare |
frequent |
|
|
Along radial nerve track |
NO |
Yes |
|
|
Painful manoeuvres |
Maximum elbow extension |
++ |
+++ |
|
Resisted wrist extension |
+++ |
++ |
|
|
Maximum finger extension |
rare |
frequent |
|
|
Fist-clenching |
++ |
+ |
|
|
Resisted supination |
+ |
++ |
|
|
Tenderness |
Epicondyle |
+++ |
rare |
|
Humeroradial joint |
often |
NO |
|
|
Annular ligament |
++ |
+++ |
|
|
Extensor muscles |
sometimes |
frequent |
|
|
Lat. bicipital groove |
NO |
frequent |
|
|
Supinator |
(+) |
+++ |
Table 3 Tests for the determination of radial nerve involvement in "epicondylitis" (From [36])
Primary radial nerve lesions account for only 5 to 10% of all cases of lateral epicondylar pain. Secondary compromise, from the peritendinous spread of inflammatory lesions, is probably more common, although no exact figures can be given. Nocturnal pain is suggestive of nerve damage. Stretching of the radial nerve may be accomplished by asking the patient to supinate the forearm against resistance, with the arm elevated forward at the shoulder, the elbow in full extension, the forearm pronated, and the wrist flexed(36). According to Lister et al.(24), three features are typical of radial nerve involvement (radial tunnel syndrome): the pain is well localized to the extensor mass, just distal to the radial head; resisted extension of the middle finger with the elbow extended produces pain at the site of the previously elicited tenderness; and similar pain is produced on resisted supination of the extended forearm. Most of my patients with lateral epicondylitis were found to have pain over and in front of the radial head; I do not think that this is due to nerve involvement. Nirschl(38) is of the opinion that this pain is indicative of degeneration of the origin of the extensor carpi radialis brevis, in the deeper layer.
In humeroradial joint disease, the epicondyle and the tendon attachments are non-tender to palpation, whereas the humeroradial joint space and the annular ligament will be tender(36). Compression of the humeroradial joint by placing the elbow into valgus may also be painful. In pathophysiological terms, it is probably rare for humeroradial joint compromise to be the sole source of pain in the lateral epicondylar region.
The most frequent cause of pain in this region are lesions of the tendinous insertions on the lateral epicondyle; in particular, the attachment of the extensor carpi radialis brevis tendon, which is partly proximal to the elbow’s axis of rotation, may be responsible for the patient’s symptoms. Any tests stressing the wrist and finger extensors will incite pain(38), which limits the diagnostic value of such tests (Figs. 15, 16). The main disadvantage of the diagnostic tests devised for the workup of lateral epicondylitis is their great sensitivity allied to poor specificity.
| CLINICAL WORKUP OF
MEDIAL EPICONDYLITIS (GOLFER’S ELBOW) |
Medial epicondylitis, commonly known as golfer’s elbow or medial tennis elbow, occurs five to seven times less frequently than (lateral) tennis elbow, and is predominant among men(38). In over 50% of the cases, there is associated ulnar nerve damage. The pain is either over the medial epicondyle, or 1 cm distal to the epicondyle, in the flexor-pronator muscle mass (Fig. 35). Passive stretching of these muscles by extension of the elbow and the wrist, with the forearm supinated, will be painful in patients with tendon attachment lesions. Similarly, the resisted contraction of the flexor-rotator group will incite medial epicondylar symptoms(38). All patients presenting with this condition must be examined for possible ulnar nerve irritation.
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| Figure 35 Medial epicondylitis, with intratendinous degeneration. View at surgery. |
In order to differentiate medial epicondylitis from chronic lesions of the medial collateral ligament in throwing athletes, the patient’s arm should be placed with the elbow extended, the forearm supinated, but the wrist flexed. In this position, a valgus stress on the elbow will not produce pain in patients suffering from medial epicondylitis.
| WORKUP OF
ELBOW INSTABILITY (excluding radio-ulnar instability) |
While elbow instability is rare, it has been known for a long time. Instability has been reported as a sequela in 15 to 35% of elbow dislocation patients(20, 26). However, it was not until 1991 that a comprehensive theory of elbow instability was advanced, taking into account recent work and studies of the anatomy and the biomechanics of the elbow. In the light of this theory, O’Driscoll et al. proposed a clinical examination designed to detect the probable lesions within a spectrum comprising valgus instability, varus instability, anterior instability, and posterolateral instability(41).
VALGUS INSTABILITY
This instability may be acute or chronic.
The acute form is due to tearing of the anterior bundle of the medial collateral ligament (often associated with other soft tissue lesions); it is found mainly in elbow dislocation(54). According to O’Driscoll et al.(41), it is often associated with a fracture of the head of the radius. When, after reduction of the dislocation, the elbow is valgus tested with the forearm pronated, this instability is commonly seen(54). The condition rarely becomes chronic, since the ligament tends to heal well, probably because it is surrounded by muscles; it should, however, be noted that, in 50% of the cases, the muscles will be torn as well(41, 54). Outside the context of dislocation, acute elbow instability is rare, and is mainly confined to athletes practising throwing sports (javelin throwers, baseball pitchers)(11, 53). Sharp pain on palpation along the medial collateral ligament (rather than over the ulna) exacerbated by valgus stress with the forearm pronated is usually diagnostic. The question of the exact amount of flexion required to improve the value of the test has not yet been settled. It would appear that the ideal angle is somewhere around 60°. If the resisted flexion of the fingers or the wrist is painless, the (even rarer) condition of isolated flexor-rotator muscle rupture may be ruled out (Fig. 36).
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| Figure 36 In valgus testing, to look for a recent lesion of the medial collateral ligament, the absence of pain on resisted wrist flexion rules out a flexor-rotator muscle tear. |
Complete tears of the medial soft tissues (capsule, ligament, and flexor-rotator muscles) have also been reported(39). In addition to the signs of acute instability, there will, very often, be bruising and swelling over the medial epicondyle (Fig. 37), and signs of nerve irritation.
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Figure 37a-d Fresh traumatic lesion of the medial capsuloligamentous and muscular structures.  |
| 37a Bony avulsion of the medial collateral ligament | 37b At 3 days after the accident |
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| 37c Partial tear of the flexor-rotator muscles | 37d Complete avulsion of the medial ligament complex, with gross detachment of the capsule and the periosteum |
Chronic instability has been studied mainly by American researchers, since this form of instability specifically affects throwing athletes such as baseball pitchers(11). Valgus elbow deformity has also been found to occur in more than 30% of professional baseball pitchers(53). Chronic stretching of the medial collateral ligament causes pain on throwing, and will result in a flexion deformity in two thirds, and ulnar nerve damage in 40%, of the patients(11). Palpation of the medial collateral ligament will elicit tenderness, while valgus testing with the forearm pronated will show instability in two thirds of the elbows examined(11) (Fig. 38). These chronic instabilities will lead to impingement of the medial tip of the olecranon process on the wall of the olecranon fossa, with production of loose bodies (Fig. 39).
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| Figure 38 Chronic elbow instability, with gaping in valgus, after avulsion of the medial collateral ligament | Figure 39 Medial olecranon process impingement as a result of instability. Repeated impingement of the medial tip of the olecranon on the posteromedial trochlear surface will lead to the exfoliation of loose bodies, which may cause joint locking. |
Loose bodies in the humeroradial joint will only subsequently be induced by this impingement(53). Olecranon impingement is searched for by placing the patient’s arm in full extension, exerting valgus stress, and simultaneously palpating the posteromedial surface of the olecranon(5). If there is impingement, there will be tenderness and, sometimes, crepitation either from loose bodies or from a synovial reaction over osteophytes (Fig. 40). This instability-related impingement must be differentiated from pain without instability felt over the medial surface of the olecranon when there are radiologically demonstrable loose bodies and/or osteophytes. These lesions, which are marked by pain and gradual stiffening with loss of the last degrees of extension, are seen in boxers and in patients with primary osteoarthritis; they may also occur in “ageing athletes”(21).
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| Figure 40 Olecranon impingement is looked for by putting the forearm into maximum extension and applying valgus stress, while palpating the posteromedial aspect of the olecranon. Impingement with instability must be distinguished from pain without instability as seen chiefly in “ageing” athletes. | |
VARUS INSTABILITY
Varus instability is also seen in elbow dislocation. Chronic instability is rare, perhaps because the elbow is rarely stressed with a pure varus force(41, 42). For this instability to occur, there must be a complete tear of the lateral collateral complex. For mechanical reasons, examination for varus instability must be performed in pronounced flexion (to at least 70°), since it is in this position that the ligament is maximally relaxed.
ANTERIOR INSTABILITY
Anterior instability is seen in olecranon fractures, which pose a management rather than a diagnostic problem.
POSTEROLATERAL INSTABILITY
Posterolateral instability is thought to be the most frequent form of elbow instability. The pattern is one of rotational displacement of the ulna (and the radius) on the humerus, leading to supination (or external rotation) of the ulna in relation to the humerus(41). The first studies, in particular those by Josefsson et al.(20), showed elbow dislocation to be consistently associated with a rupture of both collateral ligaments. However, the comparative rarity of instability after dislocation did not fit in with the fundamental role (at least in experimental studies) of the anterior bundle of the medial collateral ligament(50). Recent studies by O’Driscoll et al.(41) and Regan et al.(48) showed that dislocation may occur around an intact medial collateral ligament if the dislocating force acting on a forearm in external rotation (or supination) exerts an axial stress in flexion and in valgus. These studies confirm the results of earlier experimental work by Søjbjerg et al.(50), and contradict the previously held idea that elbow dislocation results from hyperextension. Witvoet and Tayon have given a good description of these rotational subluxations that occur with the elbow flexed when carrying a load. These authors, as well as others(45, 56), also describe posterolateral capsular distension, which provides a rationale for the treatment of recurrent dislocation by posterolateral stabilization. This recognition of posterolateral instability as a distinct entity provides an explanation of “valgus instability” with lateral lesions. Posterolateral instability is associated with external rotation (supination) of the ulna during testing in valgus, with the forearm supinated (Fig. 41). This instability disappears during valgus testing with the forearm pronated, because, under these conditions, the structure being tested is the medial collateral ligament(41, 44).
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Figure 41 Posterolateral instability following elbow dislocation, in a 25-year-old patient. Radiographs taken under general anaesthesia show posterolateral subluxation of the radial head during forearm supinating stress. |
O’Driscoll et al. describe three stages of instability. Stage 1 is posterolateral rotatory instability. According to these authors, the lateral ulnar collateral ligament is torn at this stage; however, there is considerable controversy concerning this idea. Patients with this lesion will have a positive lateral pivot shift test. The lesion may occur as a result of dislocation, but is also seen after the elbow has been subjected to a varus stress(37). Stage 2 is characterized by incomplete dislocation, with the ulna perched on the trochlea. Stage 3 shows complete dislocation, with the coronoid process behind the humerus(41). O’Driscoll et al. also distinguish between a Stage 3a, in which the anterior bundle of the medial collateral ligament is intact, which means that the elbow will be stable in valgus following reduction; and a Stage 3b, in which this ligament is torn, resulting in gross instability after reduction(41).
Patients suffering from posterolateral instability will have pain and report a sensation of snapping or catching(37, 41). These symptoms are particularly marked in near-extension with the forearm supinated(41). An extension deficit is seen in one third of the patients(37). Recently, there have been several reports of instability in post-traumatic cubitus varus(1, 2, 28). While there is still some controversy on the subject, it would, in the light of the most recent studies, appear that the main structure that has been damaged is the lateral collateral ligament(44). The lateral pivot shift is enhanced if the lateral collateral ligament is transected, or if all the collateral ligaments are cut(44). The division of the other ligaments, in particular that of the lateral ulnar collateral ligament, would appear to cause less destabilization. The posterolateral capsular distension seen in chronic instability would appear to be the result of the lesions, rather than a lesion required for the instability to occur.
The lateral pivot shift test, which reproduces the instability noted by the patients, may be performed in two ways. The most efficient method consists in placing the extremity over the patient’s head (Fig. 42). The examiner holds the wrist and the elbow. The forearm is fully supinated, and valgus stress is applied as the elbow is moved from the fully extended position to a flexed position(41). The method constitutes an apprehension test, since, in the awake patient, the manoeuvre is very uncomfortable, while it is virtually impossible to elicit frank subluxation(37). General anaesthesia (or the intra-articular instillation of a local anaesthetic) would be required in order to produce a snap at about 40° of flexion, where the subluxation reduces(37, 41). Prior to this reduction, a posterolateral prominence is produced by the subluxation of radial head, and a dimple may be seen in the soft spot area between the radial head and the capitulum(41). The test may also be performed with the arm held internally rotated at the side, with the patient recumbent(40). The forearm is supinated, and the elbow is taken from full extension into flexion while applying valgus moments and axial compression force(40) (Fig. 43). The results are the same as in the “overhead” test described above.
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Figure 42 Performance of lateral pivot shift test, as proposed by O’Driscoll et al. The examiner holds the wrist and the elbow. The forearm is supinated, and a valgus stress is applied as the elbow is taken from extension into flexion. The “snap” noted by the patients can only be reproduced under general anaesthesia; it occurs around 40° of elbow flexion. Inset: Diagrammatic representation of rotatory subluxation of ulna on humerus around the pivot of the medial collateral ligament |
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Figure 43 Performance of lateral pivot shift test on a recumbent patient. The arm is placed alongside the body, in full internal rotation. The forearm is supinated, and axial compression and valgus stress are applied as the elbow is moved from the fully extended to a flexed position. |
Acknowledgements
I am indebted to Prof. Thierry Bègué for his comments and corrections;
to the radiology team at the Clinique Jouvenet, for their assistance; and
to Ms Angèle Travadel, for help with the illustrations.
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References
1. Abe M., Ishizu T., Nagaoka T., Onomura T. Recurrent posterior dislocation of the head of the radius in post-traumatic cubitus varus. J.Bone Joint Surg. 1995 ;77B :582-585. |