Diagnosis of pain in the joints

The main complaints in patients with articular syndrome also include complaints of restriction of movement in the affected joint or joints, morning stiffness, swelling and changes in joint configuration, crunching, clicking in it during movement (crepitation), gait alteration. The duration of morning stiffness is understood as the time that the patient needs to "develop" the joint. With inflammatory lesions of joints, the duration of morning stiffness exceeds 1 hour, while non-inflammatory conditions (arthrosis) can be accompanied by a short, transitory morning stiffness, which lasts several tens or less minutes. Much less common are complaints about the sensation of a foreign, foreign body in the joint (articular mouse) in the syndrome of avascular necrosis (dissecting osteochondritis), at which local necrosis of articular cartilage and underlying bone tissue develops. The fragment of the necrotic bone is then separated and moved to the joint cavity. In these cases, pain in the joint is accompanied by periodic blockade of the joint. In addition, complaints of muscle pain (myalgia), pain in the ligaments and tendons are important. Redness of the affected joints causes suspected septic arthritis, acute rheumatic fever (rheumatic fever), but is sometimes a sign of a malignant tumor.

General complaints include elevated body temperature, as well as other complaints that reflect the presence and severity of intoxication syndrome, such as weakness, lethargy, unmotivated capriciousness, malaise, behavioral changes in the patient.

After a survey and a general examination, the doctor proceeds to a more detailed examination of individual parts of the body.

Visually determined characteristics of the joints, such as volume, symmetry, configuration. The asymmetry of the joints often happens with the shortening of one of the limbs (hemiathrophy - underdevelopment of the limb, hemihypertrophy - one-sided increase in the limb). Exclusion of the presence of swelling, that is, the increase in the joint in the volume with a certain smoothening of its contours (more often it occurs due to edema of periarticular tissues or effusion into the joint cavity), its deformation - persistent and rough changes in the shape of the joint (in the presence of bone growths), joint defogation - uneven configuration changes (due to proliferative or exudative processes). The absence / presence of changes in the soft tissues over the affected joint is indicated - pallor or hyperemia of the skin, pigmentation, fistula. Muscular atrophy, limitation of joint mobility, forced limb position, flatfoot are revealed.

The presence of flat feet (lack of visible longitudinal, transverse arches of the foot), clubfoot, a high arch of the foot ("hollow" foot), varus or valgus deformity causes persistent arthralgias not only in the foot, but also in the knee and hip joints.

Palpatorally, it is possible to determine the local temperature increase over the affected joint (for example, with rheumatoid arthritis) or its decrease in the presence of trophic disorders syndrome, vascular thrombosis. Normally, the temperature of the skin over the knee joint is lower than that of the tibia. In addition, palpation reveals the presence of soreness. Soreness in palpation in the joint area is the best indicator of the presence of synovitis. In the examination, two types of palpation are used:

• superficial palpation - application of the rear of the hand or easy stroking with the fingertips of the affected area; this method determines the temperature, soreness, the presence or absence of swelling of the joint, bone changes (exostosis, for example);
• deep palpation - allows to identify the effusion in the joint cavity, local soreness, not detected with superficial palpation.

The palpation method helps in the detection of "rachitic rosaries" ("rachitic rosary"), "bracelets", "strings of pearls," rickets of the cranial vault, and others. With deep palpation, it is advisable to use the "thumb rule". In this case, palpation is performed in such a way that the palpation effort causes a blanching of the nail bed of the doctor's thumb. Caution is given to deep palpation with severe soreness of the affected joint or bone.

It is very important to study the function of the joints with all passive and active movements (flexion and extension, withdrawal, reduction, rotation). Passive refers to the movements that the doctor does without the help of the subject, and the active movements are performed by the patient himself. The apparent discrepancy between the volume of active and passive movements allows one to think about the localization of the pathological process in the periarticular tissues, while the same limitation of the volume of active and passive movements is characteristic of the joint process proper.

At the examination, it is possible to determine the increase in joint mobility (hypermobility) - with Ehlers-Danlos syndrome, Marfan syndrome, Down's syndrome, family hypermobility of joints, and restriction of its mobility - for contractures, ankylosis, spastic paresis and paralysis, congenital hip dislocation, juvenile epiphysiolysis of the head of the hip joint.

In practice, several simple tests are used to diagnose joint looseness - overextension in the elbow and knee joints (by more than 10 °), extension of the first finger of the wrist before touching the front surface of the forearm, bending the trunk with free palms touching the floor, extension of the fingers of the wrist when the axis of the fingers becomes parallel to the axis of the forearm, dorsal flexion of the foot more than 20 ° from the right angle between the dorsal surface of the foot and the front surface of the shin. For the diagnosis of joint hypermobility syndrome, at least 3 criteria are required. In addition, in pathological conditions, accompanied by weakness of connective tissue, there is a positive symptom of Gorlin. It is considered positive if the subject can touch the tip of the nose.

Sometimes the diagnosis of lesions of various joints helps to conduct other special tests.

Rotational test - passive performance by the patient in full external rotation of the shoulder - allows the doctor to doubt the presence of the pathology of the humeroscapular joint.

If suspected of hip injury, a sample of "rolling the log" and a Trendelenburg test are carried out. The "rollover" test is performed in the leg extension position. The doctor, having grasped the thigh and the patient's shin, rotates them outward. The hip joint is the point of rotation. If there is a limitation of the amplitude of the internal and external rotation of the leg due to pain in the inguinal region, this confirms the pathology of the directly hip joint. Normally, in a patient standing on one leg, the reduction of the middle gluteal muscle on the side of the load bearing leg leads to an increase in the opposite half of the pelvis. To suspect the pathology of the hip joint, in which the weakness of the middle gluteal muscle develops, it is possible in the event that this rise does not occur (Trendelenburg's positive test).

Syndromes of multiple developmental defects, accompanied by hypermobility of the joints and arthralgia, arthritis

Nosological form, catalog number of McCusick	Hypermobility of joints and other basic diagnostic criteria
Syndrome of family hypermobility of joints (MIM: 147900)	Family form of varying degrees of hypermobility of the joints. Sometimes combined with hyperextension of the skin
Syndrome of marfanoid hypermobility of joints (MIM: 154750)	Marfanoid phenotype, increased elasticity and brittle skin, mitral valve prolapse, aortic aneurysm, etc.
The syndrome of Larsen (MIM-150250, 245600)	Congenital dislocations of large joints, unusual face, saddle nose, cylindrical fingers
Syndrome of nail-patella (M1M: 161200)	Dislocation and hypoplasia of the patella, onychodystrophy (gene localized at 9q34)
Syndrome of family recurrent patellar dislocation (MIM: 169,000)	Hypermobility of joints, recurrences of patella dislocation
Syndrome of hydrocephalus, tall, hypermobility of joints and kyphoscoliosis (MIM: 236660)	Hydrocephalus, high growth, thoracolumbal kyphosis, signs of prolapse of the heart valves without pronounced regurgitation
The progeroid form of the Ehlers-Danlos syndrome (MIM: 130070)	Premature aging, hyperextension and fragility of the skin. Defect biosynthesis of proteudermatansulfate Decreased intelligence, development

The presence of effusion in the cavity of the knee joint is confirmed by a positive symptom of balloting. When checking the symptom of patellar balloting, the area above the patella is squeezed by the doctor in front, which causes the flow of the effusive fluid into the space below it and creates the impression of a "floating" patella. Knocking on the patella with your fingertips leads to "blows" on the knee of the femur, which is regarded as a positive symptom of balloting. Determine the damage to the lower surface of the patella (for example, with osteoarthritis) as a result of a femoral-patellar compression test. The patient is asked to unbend the knee joint, which is in a state of flexion. In this case, the doctor presses the patella toward the condyles of the femur. If pain occurs when the patella moves proximally along the bone surface, the sample is considered positive.

Differential diagnosis of some arthralgia

Disease	Anamnesis	Physical examination data	Laboratory and instrumental research
Diffuse connective tissue diseases
Rheumatoid arthritis	Morning stiffness, pain in the peripheral joints. Fatigability	Synovitis. Deformation of the joints. Rheumatoid nodules	Rheumatoid factor. Indicators of inflammation X-ray
Systemic lupus erythematosus	Fatigue. Pain in the peripheral joints, swelling The phenomenon of Raynaud. Headache. Skin changes, serositis, etc.	Skin Changes. Synovitis. Neuropathy	AHA, OzDNA, Sm Ro-antibodies C3, C4 The general analysis of urine. Indicators of inflammation
Systemic scleroderma	The Reynaud phenomenon. Fatigue. Pain in the peripheral joints, swelling. Symptoms of the esophagus, lungs	Scleroderma. Swelling of the hands. Pathology of the okolonogloc cusp in microscopy	AHA, anti-centromeric, Scl-70 antibodies. Study of esophageal motility. Pulmonary function tests
Sjogren's Syndrome	Pain in the peripheral joints, swelling. Fatigue. Dryness of the mucous membrane of the oral cavity and conjunctiva	Increased salivary glands. Dry keratoconjunctivitis. Synovitis	AHA, RO-, La-antibodies. Shermer and Rose test. Indicators of inflammation
Poliomyositis	Muscle weakness. Muscle pain. Fatigability	Muscle weakness	CK, aldolase, AHA EMG / SPNI. Muscle biopsies. Indicators of inflammation
Rheumatic poly-myalgia	Morning stiffness. Pain in the shoulder, hip, limbs and neck. Headache	Tenderness along the temporal artery with HKA	Increased ESR. Inflammatory indicators Biopsy of the temporal artery with suspected HCA
Seronvgative spondyloarthropathy
Ankylosing spondylitis	Morning stiffness. Pain in the peripheral joints, swelling. Pain in the lower back Pain in the cervical spine	Restriction of movements in the cervical and lumbar spine The synovitis of the peripheral joints Irit	Radiography of the lumbosacral articulation. X-ray of the spine, peripheral joints. Indicators of inflammation
Colitis arthritis	Abdominal pain, diarrhea Axial musculoskeletal pain Pain in the peripheral joints, swelling	Synovitis of peripheral joints, limitation of movements in the cervical and lumbar spine. Melena (the latent kov in feces)	Colonoscopy (X-ray contrast studies). Radiographs of the spine, peripheral joints. Indicators of inflammation
Other diseases
Sleep apnea syndrome	Fatigue. Unproductive sleep (without rest)	Without pathology	Study of the structure of sleep
Hypothyroidism	Fatigue. Pain in the peripheral joints, swelling	Thyroid enlargement	Assessment of thyroid function

The medial epicondylitis of the elbow is manifested by the non-painful pains in the elbow joint. It often occurs as a result of the flexor-pronator's over-voltage when feeding the ball, playing rugby, golf (the "golf player's elbow"). This creates an increased load on the medial ligament joint of the elbow joint, which can be accompanied by a separation of the apophysis. The lateral epicondylitis of the elbow is called the "elbow of the tennis player" and is manifested by the appearance of pain in the area of the lateral epicondyle during a provocative test - the patient grips the hand into a fist and keeps it in the unbending position, while the doctor tries to bend his wrist, holding the forearm.

All of the above means that in differential diagnosis it is necessary not so much to concentrate attention on the joint syndrome as to make a differential diagnosis between a sufficiently large list of nosological forms in order to determine what is the basis of the disease, whether the syndrome is the primary or secondary process that accompanies the whole list of diseases of various fields of medicine.

When conducting differential diagnosis, sometimes the cause of arthralgia helps to establish some laboratory studies.

Some laboratory studies useful in differential diagnosis of arthralgia

Study	Detected diseases
Clinical blood count, including platelet count	Leukemia Infectious diseases of bones, joints, muscles Systemic connective tissue diseases
Erythrocyte sedimentation rate	Infections Inflammation of the gallbladder Systemic connective tissue diseases Tumors
Radiography	Various benign and malignant tumors of bones Osteomyelitis (chronic) Diskoz (later stages) Fractures Scoliosis Rickets Displacement of the epiphysis of the tibial head Disease Legg - Calve - Perthes Leukemia
Radioisotope bone scanning	Osteomyelitis (acute and chronic) Diskoz Osteoid osteoma Malignant bone tumors and metastases Necrosis of bone due to insufficient blood supply
Activity of muscle enzymes in serum	Reflex sympathetic dystrophy Inflammatory diseases of the muscles (idiopathic or viral) Muscular dystrophy Rhabdomyolysis

[1], [2], [3], [4], [5], [6]