Pain

Bone pain has a deep, boring quality. The pain is focal in the presence of a bone tumour or infection but diffuse in generalised disorders (e.g. osteoporosis). The pain of a fracture is sharp and piercing and exacerbated by movement but relieved by rest.

Pain

In an arthritic disorder, pain is usually the most prominent complaint. Important aspects to determine are the site and severity of the pain, whether it is acute or chronic, how it is influenced by rest and activity and whether it appears during a particular range of movement.

Ask the patient to point to the maximal site of pain. Although irritation of structures close to the skin produces well-localised pain, disturbance of deeper structures produces pain that is poorly localised and eventually segmental in distribution.

The segments to which the pain is referred (the sclerotomes) differ somewhat from dermatomal distributions. Consequently, deep pain can be felt at a point some distance from the affected structure, that is, referred pain. Where joint disease exists, misinterpretation of the site of the disease process can follow (Fig. 10.5). Spinal pain can also be referred. Abnormal function in the upper cervical spine can lead to pain over the occipital region, whereas disorders of the lower lumbar spine may lead to upper lumbar back pain stemming from the fact that the posterior longitudinal ligament is innervated by the upper lumbar nerves.

Fig. 10.5 Distribution of pain arising from (a) the acromioclavicular or sternoclavicular joints, (b) the scapulohumeral joint, (c) the hip joint and (d) the knee joint.

Severity of joint pain is difficult to judge, depending, as it does, on the patient’s personality. Osteoarthritis and rheumatoid arthritis typically result in chronic pain with periodic exacerbation; septic arthritis or gout produce an acutely painful joint.

Inflammatory joint disease tends to cause pain on waking, improving with activity but returning at rest. Mechanical joint disease (e.g. caused by osteoarthritis) leads to pain that worsens during the course of the day, particularly with activity.

For certain joint disorders (e.g. at the shoulder), pain is apparent only during a specific range of movement. If confirmed by examination, this selectivity can be valuable in differential diagnosis.

Swelling and crepitus

If the patient has noticed joint swelling, elicit for how long it has been present, whether there is associated pain and whether the swelling fluctuates. A noisy joint is not necessarily pathological. Introspective individuals are likely to interpret periodic clicking in a joint, in the absence of pain, as having pathological significance. It does not. Crepitus is a grating noise or sensation; it can have both auditory and palpable qualities. Fine crepitus is more readily felt than heard, but crepitus stemming from advanced degeneration of a large joint (e.g. the hip) is readily audible.

Locking

A joint locks if ectopic material becomes interposed between the articular surfaces. It is particularly associated with damage to the knee cartilages. Ascertain if the locking occurs at a particular point during movement of the joint.

Pain and stiffness

Muscle pain tends to be deep, constant and poorly localised. If caused by local muscle disease, it is likely to be exacerbated by contraction of the muscle and relieved by rest. If the patient complains more of muscle stiffness (particularly of the lower limbs) than pain, suspect the possibility of spasticity caused by an upper motor neuron lesion.

Weakness

A complaint of global weakness is more likely in neurotic individuals than in patients with neurological disorders.

Important questions to ask include the distribution of the weakness, whether it appears related to any pain in the limb, whether it fluctuates and whether it is static or progressive. A complaint of predominant proximal weakness suggests the possibility of primary muscle disease (e.g. polymyositis or myopathy). A predominantly distal weakness is more likely to be neuropathic. If the weakness is fluctuant, and particularly if it worsens during the course of activity, you will need to consider myasthenia gravis when you come to examine the patient (see also Ch. 11). Weakness caused by sudden entrapment of a peripheral nerve (e.g. a traumatic radial nerve palsy) will be stable or even improving by the time the patient seeks medical attention. In other conditions the weakness is progressive (e.g. motor neuron disease).

Wasting and fasciculation

Both these features form an important part of the examination, but both may have been noticed by the patient and volunteered during history-taking. If the patient describes muscle twitching, ascertain whether the movement has occurred in several different muscles or whether it has been confined to one area, most likely the calf.

Cramps

Cramps are seldom of pathological significance. They are usually confined to the calves and can be triggered by forced contraction of the muscle.

Inspection

Things you are looking for include swelling, joint deformity, overlying skin changes and the appearance of the surrounding structures.

Deformity

Deformity results either from misalignment of the bones forming the joint or from alteration of the relationship between the articular surfaces. If misalignment exists, a deviation of the part distal to the joint away from the midline is called a valgus deformity and a deviation towards the midline a varus deformity (Fig. 10.6). If a deformity exists you will need later to determine whether it is fixed or mobile. Partial loss of contact of the articulating surfaces is called subluxation, and complete loss dislocation. Although these are usually traumatic, they can also be seen in inflammatory joint disease, particularly rheumatoid arthritis. Swan neck, Boutonnière and mallet are descriptive terms used for deformities of the metacarpophalangeal and interphalangeal joints of the hand (Fig. 10.7).

Fig. 10.6 Genu varum (left) and genu valgum (right).

Fig. 10.7 Deformities of the finger in rheumatoid arthritis.

Skin changes

You should palpate the skin over a joint to assess its temperature rather than relying simply on its colour. Redness of the skin over a joint implies an underlying acute inflammatory reaction (e.g. gout) (Fig. 10.8).

Fig. 10.8 Acute gout of the first metatarsophalangeal joint.

Palpation

During palpation of a joint, assess the nature of any swelling, whether there is tenderness and whether the joint is hot.

Swelling

The method of examining for an effusion will be described for the individual joints. Your first step is to determine the consistency of any swelling. Is the swelling hard, suggesting bone deformities secondary to osteoarthritis? Certain sites are particularly susceptible to osteoarthritic change (e.g. the distal interphalangeal joints of the hand) (Fig. 10.9). A slightly spongy or boggy swelling suggests synovial thickening and is particularly associated with rheumatoid arthritis. An effusion is fluctuant, that is, the fluid can be displaced from one part of the joint to another. Swellings may also arise adjacentto a joint. Again determine their consistency. Soft fluctuant swellings suggest enlarged bursae. Harder swellings occur in rheumatoid arthritis and gout.

Fig. 10.9 Osteoarthritis of the DIP joint.

Tenderness

Carefully palpate the joint margin and adjacent bony surfaces together with the surrounding ligaments and tendons. Your task is to discover whether any tenderness is within the joint or outside it, and whether the tenderness is focal or generalised. In an acutely inflamed joint, the whole of its palpable contours will be tender. If there is derangement of a single knee cartilage, tenderness will be confined to the margin of that cartilage. In degenerative joint disease, you may find tenderness in structures adjacent to the joint. Tenderness close to the joint may reflect primary pathology in bone (e.g. osteomyelitis) or in the tendon sheath (e.g. De Quervain’s tenosynovitis) (Figs 10.10, 10.11).

Fig. 10.10 De Quervain’s tenosynovitis of the wrist.

Fig. 10.11 De Quervain’s tenosynovitis. The tendons of abductor pollicis longus and extensor pollicis brevis are inflamed.

Joint movement

Next proceed to examine the range of movement of the joint, whether movement is limited by pain and whether there is instability.

To define the range of joint movement, start with the joints in the neutral position, defined as the lower limbs extended with the feet dorsiflexed to 90°, and the upper limbs midway between pronation and supination with the arms flexed to 90° at the elbows (Fig. 10.12). For accurate measurement of joint movement you will need a goniometer (Fig. 10.13) but for routine purposes your eye should allow a reasonably true estimate. Movement of a joint is either active (i.e. induced by the patient) or passive (i.e. induced by the examiner). Sometimes you need to assess both but you will generally assess active movements in the spine but passive movements in the limb joints. Restriction of active compared with passive movement is usually due to muscle weakness.

Fig. 10.12 The neutral position from which joint measurement is performed.

Fig. 10.13 Measuring the range of joint movement.

From the neutral position, record the degrees of flexion and extension. If extension does not normally occur at a joint (e.g. the knee) but is present, describe the movement as hyperextension and give its range in degrees. Sometimes there is restriction of the range of movement. For example, if the knee fails by 30° to reach the extended position, describe this as either a 30° flexion deformity or as a 30° lack of extension (Fig. 10.14). For the ankle and wrist, extension is described as dorsiflexion and flexion as plantar and palmar flexion, respectively. For a ball and socket joint, you will need to record the range of flexion, extension, abduction, adduction and internal and external rotation (Fig. 10.15). The range of joint movement varies between individuals: an excessive range of movement can be constitutional as well as pathological. Carefully note if pain occurs during joint movement. In joint disease, pain is likely to occur throughout the range of movement. In certain disease processes around the joint (e.g. in the ligaments or bursae), pain can be restricted to a particular range or type of movement. Damage of either the articular surfaces or of the ligaments related to a joint can lead to instability. You will discover this partly by finding that the joint can be moved into abnormal positions and partly, particularly for the knee joint, by observing the joint as the patient walks.

Fig. 10.14 30° flexion deformity of the knee.

Fig. 10.15 Description of joint movement according to the type of joint.

Inspection

Look for evidence of muscle wasting, for signs of abnormal muscle bulk and for spontaneous contractions.

Palpation

Muscle palpation is of limited value. If the muscle is infected or inflamed it is likely to be tender. Most myopathies are painless but there are exceptions (e.g. the acute myopathy occurring in alcoholics). Muscle tenderness can also occur in neurogenic disorders (e.g. the peripheral neuropathy of thiamine deficiency can lead to marked calf tenderness).

Testing muscle power

You should follow the UK Medical Research Council classification (p. 363) when testing and recording muscle power. Remember to make allowance for sex, age and the patient’s stature. If the muscle itself, or the joint that it moves, is painful then power will be correspondingly limited. Patterns of muscle weakness are particularly important in neurological diagnosis. Is the weakness global, does it predominate distally or proximally in the limb, does its distribution fit with either a peripheral nerve or root distribution? Sometimes muscle power is decidedly fluctuant: there is a sudden give, alternating with more effective contraction. Although this pattern can occur in myasthenia gravis, it is usually the reflection of a nonorganic disability. If muscle fatigue is a prominent symptom assess it objectively. For example, for the deltoid, ask the patient to abduct the shoulder to 90°. Test power immediately, then after the patient has held that posture for 60 seconds.

You will need to be selective when deciding which muscles to test. Your choice will be guided partly by the patient’s complaints, both in terms of their distribution and their quality.