Torsional Phenomena

Torsional phenomena occur in at least half the infant and toddler population, varying considerably in degree. In a child whose feet turn inward, you must first decide whether it is the feet, femora, or tibias that are responsible. Does the torsion originate above or below the knee?

Internal femoral torsion (femoral anteversion)

When children have internal femoral torsion, the patellas show internal strabismus (Fig. 15–1). Gently rotate the knees so that the patella face forward. If internal femoral torsion is the problem, the feet suddenly and miraculously point directly forward.

FIGURE 15–1 Internal femoral torsion: internal strabismus of the patellas.

Once you understand the in-toeing mechanism, it becomes obvious that special orthopedic shoes, mistakenly prescribed as corrective, usually exaggerate the in-toeing because of their sheer weight. Perfectly normal shoes almost invariably also exaggerate in-toeing. It usually helps to demonstrate this phenomenon to the parents by having the child walk with and without shoes, after which they frequently realize that the problem is really not as bad as it seems.

Internal tibial torsion

Internal tibial torsion is a normal phenomenon seen in children 6 to 18 months old. It is noticed especially when they begin to walk and can vary greatly in degree. If the patellas point directly forward and the feet appear normal in a child with in-toeing, the likely cause is tibial torsion. As with femoral anteversion, the deformity typically appears worse when the youngster puts on shoes and may cause the child to stumble a bit more than average. Reassure the parents that this phenomenon disappears in most children by age 2.

Bowleg (genu varum) and knock knees (genu valgum)

Mild lower extremity bowing is the norm in infants and young children (Fig. 15–2). Internal tibial torsion often accompanies physiologic bowing and accentuates the bowed appearance. No treatment is necessary. By age 2 years, physiologic bowing spontaneously corrects itself in most children. Many healthy children, including those who have had physiologic bowing as toddlers, gradually convert to develop some degree of genu valgum after age 2 years (Fig. 15–3), which usually disappears spontaneously by age 8 years.

FIGURE 15–2 Genu varum (nonrachitic bowing of the legs), a transient normal variant requiring no treatment.

FIGURE 15–3 Physiologic knock knee, a self-correcting condition that requires no treatment.

In a few children, physiologic bowing or knock knee may be quite marked, raising concerns about possible underlying disease. If bowing increases after the child begins to walk, you should rule out pathologic causes, such as Blount disease, rickets, and metaphyseal dysplasia. Genu valgum may also develop in extremely obese children, the result of bearing excessive weight. It may also occur in pathologic conditions, such as metabolic bone disease (rickets or renal osteodystrophy).

Metatarsus varus (forefoot adduction)

In metatarsus varus, the forefoot turns inward in relation to the long axis of the heel (Fig. 15–4). The critical clinical issue is to determine whether the foot deformity is fixed or flexible. Mild to moderate flexible metatarsus varus usually corrects itself, because it is the result of intrauterine position, or packing. A severe or fixed metatarsus varus may require serial casting or an orthotic device. If you are in doubt about the severity of this condition in a child, consult a pediatric orthopedist.

FIGURE 15–4 Metatarsus varus. The key clinical issue is the extent of flexibility of the deformity.

Toeing-out

Toeing-out, sometimes quite marked, is noted when some perfectly healthy youngsters begin to walk. This eversion of the legs, not the feet, may look peculiar but does not interfere with walking and generally corrects spontaneously 6 to 12 months later. It is usually due to the external rotation of the hips or to the external tibial torsion. When it is due to the external rotation of the hips, rotating the hips to a normal position during the examination corrects the abnormality and helps the parents understand its nature. No treatment is necessary.

Flat feet

Flat feet are the norm in children younger than ages 2 to 3 years and in older children who show greater than average joint mobility. Usually asymptomatic, this normal variant is often simply part of generalized hypermobility. In such children, the normal body weight is sufficient to cause flattening of the feet. When the youngster sits on a table, the longitudinal arch miraculously reappears as the feet are suspended in space (Fig. 15–5).

FIGURE 15–5 With flexible flat feet (A), the longitudinal arch miraculously reappears when the child is not weight bearing (B).

Toe-walking

The most common condition that causes pathologic Achilles tendon tightening and gastrocnemius spasm is spastic cerebral palsy, but toe-walking can also be seen occasionally in perfectly normal children who favor their toes in the early months of walking before they develop a mature heel-toe gait. Toe-walking in normal children tends to be intermittent, and they tend to rest with their feet flat on the floor when they stop walking. By contrast, children with cerebral palsy have persistent toe-walking and also often circumduct their legs while walking; they also have increased muscle tone, hyperreflexia, and tight heel cords. Although a congenitally short Achilles tendon does occur, it is rare. Proximal muscle weakness, as in muscular dystrophy, and a tethered spinal cord also must be excluded in the child with toe-walking.

Hip pain

Knee pain

Knee pain in children is often due to one of the following causes:

Foot pain

Poorly fitting footwear is a common cause of foot pain in children. Other causes are tarsal coalition (a coalition between the tarsal bones characterized by a rigid flat foot), Köhler disease (avascular necrosis of the navicular bone), and Freiberg disease (avascular necrosis of the second metatarsal head).

Back pain

Consider osteomyelitis of a vertebral body, discitis, or tumor in all children who present with back pain. Other causes are discussed here.

Trauma

Whether accidental or inflicted, trauma can cause localized pain wherever it occurs. Always determine whether the child’s complaints and physical findings are compatible with the extent of injury reported.

Infection

Bacterial infections, such as septic arthritis and osteomyelitis, usually affect a single joint or bone, particularly the knee or hip; however, multiple sites are occasionally involved. If a child is febrile and has marked pain with movement of a joint or marked bony tenderness, you should suspect infection. Redness overlying the tender area should heighten your suspicion of bacterial infection. Specific infections and postinfectious illnesses may give rise to particular patterns of joint involvement as described here. Acute rheumatic fever produces a postinfectious migratory arthritis affecting any single joint for approximately 1 week or less. Lyme disease (a tick-borne infection) causes arthritis that usually affects a few joints, particularly the knee, shoulder, and elbow. Viral infections may be associated with acute pain in joints, muscles, or both, that usually resolves rapidly with symptomatic treatment.

Tumors

Juvenile idiopathic arthritis

Arthritis is defined by the American College of Rheumatology as the presence of joint swelling or two or more of the following findings:

Although any joint may be affected, certain types of JIA involve specific joints predominantly, providing essential diagnostic clues.

Oligoarticular JIA involves four or fewer joints during the first 6 months of disease, most commonly the knees, ankles, or elbows but not the hip joint. It primarily affects young girls ages 1 to 3 years and is frequently associated with asymptomatic uveitis and a positive antinuclear antibody test result. In a 2-year-old girl who has hip pain, other causes should be sought, such as septic arthritis and leukemia.

Polyarticular rheumatoid factor (RF)-negative JIA involves five or more joints during the first 6 months of disease, most often the knees, wrists, elbows, and ankles. The cervical spine and temporomandibular (TM) joints are also often involved.

Polyarticular RF-positive JIA also involves five or more joints in the first 6 months of disease and often has symmetric small-joint disease of the hands. Without aggressive treatment, this subtype, which is equivalent to adult rheumatoid arthritis, will cause joint damage and deformities. Fortunately, this subtype makes up only about 5% of all JIA.

Systemic JIA is characterized by high spiking fevers, an evanescent rash, variable internal organ inflammation that may lead to hepatosplenomegaly, lymphadenopathy, pericarditis, other serositis, and chronic arthritis. Either an oligoarticular or polyarticular pattern of arthritis may be seen. You must always exclude infection and malignancy before making a diagnosis of systemic JIA.

Enthesitis-related arthritis commonly affects the large joints below the waist, particularly the knees, ankles, and hips. Boys older than 8 years who carry the genetic marker HLA-B27 are more likely to be affected. Buttock pain due to sacroiliitis and back pain may also occur but usually appear later in the course of disease. Enthesitis resulting in pain in the heels, over the tibial tuberosities at the knees, and under the feet, is also characteristic of this subtype of JIA.

Psoriatic arthritis may affect a few or many joints in a child who has psoriasis or a strong family history of psoriasis. Dactylitis or a sausage-shaped finger or toe should make you think of psoriatic arthritis. Depending on the age at which it starts, the arthritis may look like oligoarticular JIA in younger children or more like enthesitis-related arthritis in older children.

Other rheumatic diseases

The connective tissue diseases, including systemic lupus erythematosus (SLE), juvenile dermatomyositis, mixed connective tissue disease, and scleroderma, may manifest as arthritis, arthralgia, myositis, myalgias, or tenosynovitis that causes musculoskeletal pain. Most of these disorders will have characteristic findings that allow you to make the diagnosis. The exception is SLE, which sometimes presents with arthritis and fatigue as the only initial symptoms. An index of suspicion, particularly in the adolescent girl with joint complaints, as well as appropriate use of serologic testing, can lead to the correct diagnosis. The various forms of primary systemic vasculitis may also manifest as arthritis. Of these, Henoch-Schönlein purpura and Kawasaki disease are by far the most common in children.

Growing pains

So-called growing pains have no connection with growth (aside from their occurrence in growing children). The term growing pains is used to describe limb pains that follow a characteristic pattern and are found by careful physical examination not to be associated with any detectable disease. They most commonly occur in children between ages 2 and 6 years. The limb pains occur mainly at night, often after intensive physical activity, and can cause severe leg pain. Typically, affected children are asymptomatic during the day, and their gait is normal.

Many children who experience growing pains go to bed without complaint but wake up 1 to 3 hours later complaining of leg pain that is often severe enough to make them cry. Most complain of bilateral calf, shin, or thigh pain, or, more vaguely, of pain in the entire leg. The trunk and upper extremities are rarely affected. Commonly, a parent of such a child experienced similar pains in childhood. Affected children often find relief from a single dose of acetaminophen or from massage, in contrast to children with an underlying pathologic cause of pain, who almost never ask their parents to rub their legs. A hot bath immediately before bed seems to help prevent pains in some children. If the history is atypical or if the child has a limp, joint swelling, or bone tenderness, do not label the problem as growing pains.

Benign hypermobility

Benign hypermobility syndrome is a common cause of joint pain, particularly in the knees, ankles, and fingers. Occasionally, the affected joints appear swollen for brief periods, but the swelling resolves spontaneously. The symptoms are episodic and may be exacerbated by exercise. The clinical findings that allow you to make a diagnosis of hypermobility are listed in Box 15–1.

Diffuse idiopathic musculoskeletal pain

Diffuse idiopathic musculoskeletal pain is a poorly understood condition characterized by chronic widespread musculoskeletal aching and stiffness that occurs predominantly in healthy teenaged girls. Patients often complain of fatigue, poor sleep, and awakening unrefreshed. They may have associated chronic headaches or irritable bowel syndrome. In some patients, physical examination reveals exquisite tenderness at characteristic soft tissue sites, meeting the criteria for fibromyalgia. The cause of fibromyalgia is unknown. Fibromyalgia may be primary or secondary, superimposed on a recognizable painful condition or underlying disease. The diagnosis, which is suggested by the history and the finding of specific tender points on physical examination, requires exclusion of other causes of widespread aches and pains, including hypothyroidism and depression.

Localized idiopathic musculoskeletal pain

Localized idiopathic musculoskeletal pain is typically constant, severe pain that can involve any part of the body. The leg is more commonly affected than the arm, and distal involvement is more common than proximal. The pain often significantly interferes with normal functioning and is frequently accompanied by allodynia (pain generated by stimuli that are not normally painful). The pain may or may not be associated with symptoms and signs of autonomic dysfunction, including cool temperature, mottled purple discoloration, increased sweating or marked dryness, and diffuse swelling of the painful area. Minor injury not infrequently precedes the onset of pain, but progressive disability follows that is not consistent with the inciting event. The disorders reflex sympathetic dystrophy and chronic regional pain syndrome types 1 and 2 are encompassed in the category localized idiopathic pain. As in the child with diffuse idiopathic pain, other diseases that could reasonably explain the symptoms must be excluded before this diagnosis is made.

Stress

Ask about stress. Psychosocial stresses trigger not only benign abdominal pain or tension headaches but also benign musculoskeletal pain, particularly in teenagers with diffuse or localized idiopathic pain syndromes. Stress may not be immediately obvious, but observation and questioning may reveal a highly motivated overachiever who is under considerable family pressure, other recent stresses at home or at school, or an abnormally symbiotic parent-child relationship. Sexual abuse may be a hidden cause of unexplained musculoskeletal pain, and you should suspect physical abuse if the child has extensive bruising or multiple fractures.

Timing of symptoms

Find out when the symptoms began, and determine their course. Musculoskeletal pain that has been unchanged for many years is unlikely to be due to significant disease. A notable exception is osteoid osteoma, which may cause persistent mild and inconstant symptoms for several years before medical attention is sought. With osteoid osteoma, pain typically occurs at night and is relieved by acetylsalicylic acid (ASA) and other NSAIDs. Malignant bone tumors have a much more fulminant course but may cause pain with few other symptoms for weeks or months before diagnosis.

Locating pain sites and establishing severity

Asking a child, “Show me with one finger where it hurts,” and asking the parents to describe where the child usually complains of pain may help localize the cause of musculoskeletal pain in children.

Although children find it difficult to describe their discomfort, they give fairly consistent descriptions in several disorders. For example, they describe growing pains as heavy, deep aching, or cramping that, unlike most other musculoskeletal pains, is relieved by massage. Children with diffuse idiopathic pain syndromes often describe their pain as ill-defined, diffuse aching pain with stiffness; in some localized idiopathic pain syndromes, the pain may be described as burning pain.

Having the child or parent describe the severity of the pain does not help distinguish an organic from a nonorganic cause because significant disease may cause moderate pain only, whereas a child with a benign condition may complain of severe pain. Knowing whether the pain interferes with function and how it affects the child and family helps you evaluate its severity. Musculoskeletal pain with no obvious organic basis may produce weeks of school absence in the child with diffuse or localized idiopathic pain, whereas many children with JIA and obvious organic joint disease rarely miss school and manage to keep up with their peers.

Aggravating and relieving factors

Discovering what alleviates the pain or worsens it is a diagnostic aid. Increased activity aggravates musculoskeletal pain from mechanical causes, such as patellofemoral malalignment, which is aggravated by climbing stairs, deep knee bends, and prolonged periods of knee flexion. Other mechanical causes of pain, such as Plica syndrome, Osgood-Schlatter disease, joint hypermobility, and stress fracture, are all aggravated by exercise.

Pain from a mechanical cause is usually less severe in the morning and worsens with activity during the day. By contrast, pain that is worse in the morning and gradually improves with increased daytime activity characterizes inflammatory disease and suggests arthritis. Growing pains occur at night and disappear the next morning, only to recur on subsequent nights. Pain from an osteoid osteoma worsens at night but is usually unilateral if the lesion arises in an extremity. The dramatic relief of pain with ASA or other NSAIDs can provide a clue to the diagnosis. By contrast, growing pains are almost always bilateral. Although pain from a malignant bone tumor may intensify at night, it usually remains constant throughout the day. Often, pain from infection is fixed, day and night. Pain due to diffuse and localized idiopathic pain syndromes is frequently unremitting during the day but does not awaken the child at night.

Preceding trauma

Always ask about possible trauma, because subtle injuries, even a minor penetrating wound to the foot or a rose thorn prick to a finger, can give important clues to the child’s problem. Not infrequently, a minor fall brings attention to a previously unrecognized swollen joint secondary to JIA or another underlying abnormality. Occasionally, minor trauma can cause a pathologic fracture in the presence of an underlying abnormality, such as a bone cyst. If the child has a bleeding disorder, a minor injury may lead to significant bleeding in a joint.

Repetitive minor trauma can result in an “overuse” syndrome, so ask about a child’s participation in sports, which might cause little leaguer’s shoulder, little leaguer’s elbow, or tennis elbow. Also, recent vigorous physical activity after a prolonged period of inactivity increases the risk of a stress fracture.

Previous infection

Elicit details of any previous infections. A sore throat due to β-hemolytic streptococcal infection or scarlet fever, preceding migratory joint symptoms by a latent period of 2 to 5 weeks, suggests acute rheumatic fever. A gastrointestinal or genitourinary infection 2 to 4 weeks before the onset of joint pain suggests a reactive arthritis. Always ask about recent treatment with antibiotics or other medication. Antibiotic use for any reason can result in a partially treated septic arthritis or osteomyelitis, obscuring the typical clinical manifestations; some medications can produce drug reactions or serum sickness. Certain viral infections, especially influenza A and B, may be followed by the sudden onset of acute muscle pain and tenderness, usually affecting the calf muscles. The calf pain is often so severe that the child refuses to walk but will crawl around on hands and knees. This acute myositis usually resolves spontaneously in a few days.

A history of a tick bite, living in or visiting an area endemic for Lyme disease, or a rash suggestive of erythema migrans, raises the possibility of Lyme disease, named after the town of Old Lyme, Connecticut, where it was first recognized.

Associated symptoms and signs

Joint pain associated with early-morning stiffness suggests inflammatory joint disease. The parent may report that the child moves slowly on awakening and refuses to climb stairs or “walks like a little old man.” The morning stiffness may last from 5 or 10 minutes to several hours. Recurrent stiffness after an afternoon nap or a long car ride, known as the gelling phenomenon, also characterizes inflammatory disease. Swelling, redness, and warmth over one or more joints also suggest inflammatory disease. A history of limping always indicates a significant problem, even if other symptoms are minimal.

If you suspect an underlying connective tissue disorder, take a detailed history, including a complete functional inquiry, because these illnesses frequently affect multiple organ systems. Has the child experienced fever, weight loss, anorexia, or fatigue? A few specific questions about the head and neck provide a clue in children whose multisystem complaints suggest an underlying connective tissue disorder. They include questions about alopecia, recurrent mouth ulcers, sicca symptoms (dry eyes, dry mouth), facial swelling, and dysphagia.

Constitutional symptoms, such as fever, fatigue, anorexia, and weight loss, may also occur with infection, systemic-JIA, or malignancy, particularly leukemia or neuroblastoma. Abdominal pain, diarrhea, and fever should raise the suspicion of inflammatory bowel disease or bowel infection, such as Yersinia infection with joint involvement. A detailed history may also uncover symptoms suggesting fibromyalgia, such as constant fatigue, generalized stiffness, recurrent headaches, abdominal pain, and symptoms of anxiety or depression.

Asking about previous musculoskeletal complaints is important. The presence of an underlying illness, such as hemophilia, hypothyroidism, inflammatory bowel disease, or cystic fibrosis may also establish the etiology of the musculoskeletal complaint. Immunodeficiency states in a child with a history of recurrent infections, may manifest as arthritis that is clinically indistinguishable from JIA. Recent immunization, particularly with rubella vaccine in older children, can occasionally cause an arthritis that may persist for weeks.

Because adult rheumatoid arthritis is common, a family history of this disease has little diagnostic value. Certain forms of arthritis, particularly those associated with the genetic marker HLA-B27, do have a genetic predisposition, so ask about a family history of ankylosing spondylitis, psoriasis, inflammatory bowel disease, Reiter syndrome, and other collagen vascular disorders. A positive family history may also be seen with Legg-Calvé-Perthes disease and osteochondritis dissecans.

Observation

Watch the child closely. Observe for any obvious abnormalities while the child is walking or playing. If the youngster is old enough, begin the examination with nonthreatening activities that will help establish the extent of physical limitation. To detect subtle abnormalities in one limb, ask the child to hop on one foot at a time while you hold one of his or her hands. Note whether the child grasps your hand more firmly when supported on the affected leg (Fig. 15–6). Ask the youngster to walk on the heels and toes to determine whether there is impairment due to muscle weakness or due to local pain or tenderness. A simple screening technique to assess either strength or lower extremity joint disease is to ask the child to squat and walk across the room like a duck (Fig. 15–7). A normal “duck-walk” makes significant joint disease in the knees and hips extremely unlikely.

FIGURE 15–6 When there is pain or weakness in one leg, the child may grasp the physician’s hand for added support when hopping on the affected leg.

FIGURE 15–7 Squatting like a duck is a good screening test for weakness or other lower limb problems.

To test pelvic girdle muscle strength, ask the child to sit on the floor and then stand up; often with proximal muscle weakness, the child cannot rise from the floor without assistance or without either using a chair or table or climbing up the legs (placing the hands on the thighs to assist), a phenomenon (Fig. 15–8) known as the Gower maneuver.

FIGURE 15–8 The Gower sign. A child with weak proximal leg muscles “climbs up her legs” when getting from the floor to a standing position.

With the child sufficiently undressed to give you a good view of the legs and pelvis, observe the gait during walking and running over a good distance. Check the mechanics of walking, including heel strike, follow-through, and push-off. Be sure that flexion and extension of the ankles, knees, and hips are normal. Examine the gait with the child’s shoes on, then with the child barefoot. Ill-fitting shoes can cause foot pain at any age.

When a child spends a shorter time bearing weight on the painful leg than on his or her normal one, the gait is described as antalgic. The following characteristic gait patterns help localize the problem:

Back examination

Look at the child from behind while the youngster stands upright. If the spinal dimples are level, there is no significant leg-length discrepancy (Fig. 15–9). Inspect the lower back for the presence of a tuft of hair, midline nevi, angioma, lipoma, or a central dimple, suggesting an underlying vertebral and spinal cord abnormality. If the spinal cord is tethered by a bony spicule or fibrous band (diastematomyelia), the child may present with back or lower extremity pain or may be asymptomatic for years.

FIGURE 15–9 Spinal dimples should be level when there is no leg-length discrepancy. A, Normal. B, Child with mild overgrowth of the left leg secondary to juvenile idiopathic arthritis involving the left knee.

Next, with the child still standing, examine the back for scoliosis. Observed from behind, the shoulders should be level. Note any scapular prominence. With nonstructural scoliosis, a lateral curve is present that is flexible and is corrected with side bending to the convex side; with structural scoliosis, the curve is not corrected with side bending. A structural thoracic scoliosis leads to deformity of the rib cage, with the ribs on the convex side of the curve protruding on forward bending to produce a rib prominence on that side (Fig. 15–10). Ask the child to bend forward at the waist, keeping the knees straight and allowing the arms to hang down freely. This position accentuates even a slight rib or lumbar asymmetry. Inspect the back for compensatory secondary curves above and below the major curve. These secondary curves help keep the head aligned over the pelvis. If the child has a leg-length discrepancy, correct it before checking for scoliosis.

FIGURE 15–10 Scoliosis. Mild degrees of scoliosis (A) become more obvious when the child is asked to bend forward (B) and is inspected from the rear.

Scoliosis must be severe to produce back pain in a child; mild scoliosis cannot explain a child’s back pain and suggests some other underlying pathologic process, such as osteoid osteoma, spinal cord tumor, infection, or spondylolisthesis. If you detect significant scoliosis in a child, screen all of his or her siblings.

Examine the youngster’s back for evidence of decreased or excessive thoracic kyphosis or lumbar lordosis. Excessive thoracic kyphosis appears as round shoulders or a rounded back and, in the adolescent, may be caused by poor posture or by Scheuermann disease. In Scheuermann disease, unlike poor posture, the kyphosis persists when the child lies prone and is emphasized by forward bending. With the child bending forward, observe how the lumbar spine forms a smooth curve from the thorax to the sacrum. Back flattening in the lumbar area suggests disease ranging from chronically limited movement secondary to juvenile ankylosing spondylitis, to acute limitation from vertebral osteomyelitis, or even a spinal tumor.

Teenagers often have tight hamstring muscles that prevent full hip flexion and may appear to limit lumbar flexion; slightly bending the knees can increase the range. Hamstring tightness and marked restriction of forward hip flexion are common in patients with symptomatic spondylolisthesis with or without associated tenderness on palpation of the lower back. Perform a straight leg raising test to further assess hamstring tightness.

Be sure to differentiate hamstring tightness from a nerve root problem. With the patient supine, flex the hip while keeping the leg straight. Normally, flexion to 80° to 90° is possible. In the presence of a normal hip, limitation of flexion with pain occurring below the knee, as well as in the hamstring area, suggests nerve root disease. To help confirm nerve root irritation, flex the knee to allow further flexion of the hip, and then straighten the knee to see whether doing so induces pain (Lasègue test); then ease knee flexion to a tolerable degree and dorsiflex the ankle (Bragard test); pain with this maneuver confirms a nerve root problem.

Have the child lie in a prone position, and palpate the spine, the paravertebral muscles, and the sacroiliac joints. Test back movement thoroughly in older children. Check lateral flexion by asking the child to tilt sideways without bending forward and to touch the tips of the fingers to just below the sides of the knees. Normally, the fingertips can touch the head of the fibula (Fig. 15–11). To test rotation, first have the patient straddle a chair to stabilize the pelvis and cross the arms across the chest to stabilize the shoulder girdle; then ask the patient to rotate the trunk (Fig. 15–12).

FIGURE 15–11 Testing lateral flexion of the spine. The child can normally touch the head of the fibula with the fingertips. Make sure that the child does not “cheat” by bending forward to reach the lower leg.

FIGURE 15–12 Testing spinal rotation. Straddling the chair stabilizes the pelvis, and crossing the arms stabilizes the shoulder girdle. The child is then asked to turn as far as possible to each side.

Cervical spine examination

Facing the child, inspect the child’s neck for evidence of torticollis. In infants, palpate for a firm nontender mass in the body of the sternocleidomastoid muscle, which would suggest congenital muscular torticollis; the mass may resolve spontaneously by ages 4 to 6 weeks. Palpate for tightness or contracture of the sternocleidomastoid muscle. Measure the infant’s skull, and look for secondary facial and skull asymmetry. Facial flattening on the side of the abnormal sternocleidomastoid muscle can occur with untreated torticollis.

Next, observe the cervical spine from the side, noting the presence or absence of the normal cervical lordosis. Palpate the paravertebral muscles and the spinous processes to detect tenderness or masses. Test the range of motion—extension, flexion, rotation, and lateral flexion. Normally, the cervical spine extends so that the child’s occiput touches the upper back, and the youngster looks directly at the ceiling (Fig. 15–13A). Loss of extension is often the most sensitive test for early cervical spine involvement in JIA (see Fig. 15–13B), whereas flexion may remain normal despite significant cervical disease. To test rotation, ask the child to look toward each shoulder; the normal range is 80° to 90°. Ask the child to touch each ear to the shoulder to test lateral flexion; the normal range is 45°.

FIGURE 15–13 A, Normal degree of cervical spine extension. B, Marked limitation of extension (in juvenile idiopathic arthritis) accompanied by typical upward gaze.

Temporomandibular joint examination

Inspect the TM joint for overlying swelling just anterior to the tragus of the ear. Do not confuse this swelling with parotid gland swelling, which extends over the angle of the jaw behind and below the ear. Look for micrognathia. Mandibular growth may be impaired by arthritis affecting the TM joints in childhood (Fig. 15–14), and facial asymmetry may develop if one TM joint is more severely affected than the other.

FIGURE 15–14 Early micrognathia associated with juvenile idiopathic arthritis. In some affected children, this sign can be much more pronounced.

Test jaw movement when the child opens the mouth widely. Because the jaw is smaller on the side of the more severely affected TM joint, the jaw shifts slightly toward the affected TM joint when the child opens the mouth wide. The interdental distance—the distance between the upper and lower central incisor teeth when the child opens the mouth maximally—is at least 3 cm in a normal child (Fig. 15–15). Palpate the mandibular condyles for tenderness, and try to appreciate their normal rounded contour, which may be lost with persistent arthritis. Crepitus may be present if the cartilage separating the condyle from the temporal bone is eroded.

FIGURE 15–15 The child is asked to put her fingers in her mouth as a quick screening test for loss of interdental distance. The mouth should admit at least three fingers in the position shown.

Peripheral joint examination

Examining the peripheral joints helps document the presence or absence of arthritis. Have older children sit on the edge of the examining table; infants and younger children can sit on the parent’s lap.

The examination of each joint includes:

It is also essential to examine the bones proximal and distal to the joints. Examine the child scrupulously for bone tenderness. A useful technique to pinpoint bone tenderness uses the eraser on the end of a pencil. The periosteum is extremely sensitive to pain, and bone tenderness may result from trauma, osteomyelitis, or subperiosteal leukemic infiltrates.

Hand examination

It is least threatening for a child if you begin the peripheral joint examination by inspecting the hands. Check the fingers for psoriatic nail pitting (Fig. 15–16), clubbing, periungual erythema, nail fold vasculitic infarcts (Fig. 15–17), loss of the distal finger pulp, ulcerated fingertips, and sclerodactyly. Note any swelling, redness, deformity, or asymmetry between the two hands (Fig. 15–18).

FIGURE 15–16 Typical nail pitting associated with psoriasis.

FIGURE 15–17 The dark spots on the nail bed represent small vasculitic infarcts, seen typically in connective tissue diseases.

FIGURE 15–18 Marked swelling of the interphalangeal joints with flexion contractures in juvenile idiopathic arthritis.

Palpate the individual distal interphalangeal (DIP), proximal interphalangeal (PIP), and metacarpophalangeal (MCP) joints, searching for evidence of tenderness, increased warmth, synovial thickening, or effusion. Bimanual palpation using the thumbs and index fingers of both hands detects effusions of the MCP joints. MCP joints are located 1 cm distal to the knuckles, and swollen MCP joints cause the depressions between the knuckles, normally visible when a child makes a fist, to disappear. To assess active flexion of the small joints of the hand, ask the child to make a fist. Evaluate the passive range of motion, noting the presence or absence of stress pain, which occurs at the extreme ranges of joint movement.

Pain, swelling, and limited finger movement may also result from tenosynovitis, an inflammation of the tendon sheaths. Palpate each tenosynovial sheath for swelling, tenderness, or crepitus. Sometimes, discrete nodules, palpable in the individual tendons, may obstruct normal finger flexion and extension, causing triggering, an involuntary hesitation in flexion or extension caused by sticking of a flexor tendon within its sheath. Before concluding the hand examination, inspect the bony and soft tissue structures; cool temperature, hyperesthesia, blue mottled discoloration, increased sweating, and bizarre posturing suggest reflex sympathetic dystrophy.

Wrist examination

Inspect the wrist for deformity or malalignment. In JIA, ulnar posturing (deviation) of the wrist is not uncommon, and volar subluxation may occur with long-standing or severe disease. Examine the wrist for evidence of swelling along the joint line, which would indicate an effusion. Swelling may also be seen over the dorsum of the hand distal to the wrist joint (Fig. 15–19); its presence suggests tenosynovitis of the extensor tendon sheaths, which is confirmed if the swelling moves as the child opens and closes the fist. When the fingers are actively extended, the distal margin of the swelling moves proximally and appears to “tuck in”; hence, this phenomenon has been called the tuck sign (Fig. 15–20). Observe the range of motion at the wrist; in most children, flexion and extension to 80° to 90° are possible.

FIGURE 15–19 Swelling over the wrist and dorsum of the hand in juvenile idiopathic arthritis.

FIGURE 15–20 The tuck sign. When the child extends the fingers, the swollen extensor tendon sheath moves proximally and produces a bulge on the dorsum of the hand.

Forearm supination and pronation occur at the distal and proximal radioulnar joints. Test these movements with the child’s arm held at the side, the elbow flexed to 90° and the hand held in the neutral position with the thumbs up. Supination is normally possible to 90° (palms up) and pronation to 85° (palms down).

Elbow examination

Examine the elbow for swelling, tenderness, increased warmth, and range of motion. The elbow normally flexes to at least 145° to 150° and extends to at least neutral (complete extension) and, frequently, to 10° of hyperextension, especially in girls. Carefully palpate the elbow for swelling; you can most easily detect an effusion by moving the elbow from flexion into extension, reducing the intra-articular space. Simultaneously palpate the joint over the lateral or medial aspects to feel the fluid bulge. Examine the posterior surface of the proximal ulna for rheumatoid nodules, which may occur in the small subgroup of children with rheumatoid factor-positive polyarthritis.

Shoulder examination

The shoulder mechanism consists of the glenohumeral joint and the shoulder girdle. The deltoid muscle produces the normal rounded contour of the shoulder, a contour that is lost with anterior shoulder dislocation or with significant muscle atrophy from primary muscle or joint disease (Fig. 15–21). Inspect the shoulder for normal contour and for an effusion, which results in an anterior prominence just lateral to the coracoid process.

FIGURE 15–21 A 14-year-old girl with juvenile idiopathic arthritis. A, Her left shoulder appears normal. B, On inspection, her right shoulder shows marked atrophy of the shoulder girdle, visible anteriorly and posteriorly.

Test mobility at the shoulder joint by asking the child to perform the following active movements:

FIGURE 15–22 Testing range of motion of the shoulder. The child is asked to raise his hands above his head with palms facing each other. This boy has limited abduction of the right shoulder. Typically, he tilts his head toward the affected side when asked to perform this maneuver.

Hip examination

Ask the child to lie supine on the examining table, or reposition the younger child or infant in a recumbent position on the parent’s lap. Observing the child’s posture and position is critical in the examination of the hips because these joints are too deep to inspect directly. Suspect significant hip disease in the child who holds the hip in flexion and external rotation.

A screening test for hip disease in addition to the “duck-walk” test is the log roll, a painless test used to detect muscle spasm secondary to hip joint irritability. With the child lying supine, place your hand on the thigh and gently roll the hip into internal and external rotation, noting any resistance, which would suggest hip disease. To accurately assess the range of hip movement, you must place your other hand on the child’s pelvis to stabilize it (Fig. 15–23). When the pelvis moves, the end of hip movement has been reached. Normal hip mobility varies significantly with age and is generally greater in infants than in older children.

FIGURE 15–23 How to test hip abduction. Use one hand to stabilize the pelvis. Normal range is 40° to 50°.

Test hip flexion by asking the child to bring the knees to the chest (normal range, 120°). Move the leg laterally and medially to test abduction (normal range, 40° to 50°) and adduction (normal range, 25°). Test abduction in each leg individually; if you test the legs together, a compensatory spinal curving will create a false impression of normal leg abduction even if one hip has limited abduction.

It is best to examine hip rotation with the child lying prone and to symmetrically move the legs into external and internal rotation with the knees flexed, so that you can more easily appreciate pelvic movement, especially if you are an inexperienced examiner (Fig. 15–24). Flex the knee to 90°, move the foot outward to test internal rotation (normal range, 40° to 45°), and swing the foot inward to test external rotation (normal, 30° to 40°). The loss of internal rotation is often the first sign of hip involvement in children with joint inflammation. A valuable sign of hip disease is the external rotation of the hip as it is flexed from the extended position. The diminished abduction and internal rotation of the hip may be the earliest and sometimes the only abnormalities detected in the child with Legg-Calvé-Perthes disease or slipped capital femoral epiphysis.

FIGURE 15–24 Testing external rotation of the hip. The child should be prone. Use one hand to stabilize the pelvis. Normal external rotation is 30° to 40°.

Measure leg length from the anterior superior iliac spine to the medial malleolus, preferably with a steel tape (Fig. 15–25). It is important to position the patient supine with the legs fully extended and parallel and with the pelvis level.

FIGURE 15–25 Technique for measuring true leg length, from the anterior superior spine of the iliac crest to the inferior edge of the medial malleolus.

A fixed flexion deformity of the hip may not be obvious on your initial observation of a child. Clues to a flexion contracture include an accentuated lumbar lordosis and a tendency to stand with one knee slightly bent despite the absence of knee disease. Perform the Thomas test, to detect a fixed flexion deformity, as follows (Fig. 15–26):

FIGURE 15–26 Thomas test. A, Normal. B, Increased lumbar lordosis masking a hip flexion deformity. C, Hip flexion deformity unmasked by flexion of the other hip. Estimate the angle between the table and the patient’s leg to measure the flexion contracture.

Keep one hand under the child’s lumbar spine as the hip extends because the lumbar spine can move into lordosis and mask a fixed flexion deformity even with the other knee held to the chest. The inability to rest the leg on the table with the lumbar spine flat indicates a fixed flexion deformity. Measure the remaining angle.

Use the Trendelenburg test to evaluate a painful hip or to gauge hip girdle weakness in the older child who will cooperate. Ask the child to stand on one leg; normally, the pelvis rises slightly on the side opposite to the leg one stands on because the hip abductors contract on the weight-bearing leg. When hip abductor muscles are weak, the pelvis drops downward on the side opposite to the weight-bearing (affected) leg (Fig. 15–27).

FIGURE 15–27 Trendelenburg test. A, When the patient stands on one leg, contraction of the gluteus medius muscle on the supported side should elevate the pelvis on the unsupported side. B, With a positive Trendelenburg test result, which occurs with weakness of the hip abductors, the pelvis on the unsupported side descends. (X indicates a dimple overlying the posterosuperior iliac spines.)

The Ortolani test is used specifically to detect the “clunk” of developmental hip dysplasia in the newborn (see Chapter 4). In an older infant or a child with untreated development hip dysplasia, the result is always negative because the dislocated femoral head can no longer be reduced into the acetabulum. Late diagnostic signs of developmental hip dysplasia are a painless limp, asymmetric posterior skin folds on the thighs, a shortened thigh (because the femoral head no longer remains in the acetabulum), and tightened muscles around the hip joint, which restrict hip movement, particularly abduction.

Knee examination

Inspect the knee for obvious swelling, redness, or evidence of injury. The first sign of a knee effusion is the loss of the normal concavity along the medial side of the patella. Check for the characteristic swelling over the tibial tuberosity seen in Osgood-Schlatter disease. Inspect the quadriceps muscle for wasting. Note any knee deformity. The most common knee deformity seen in children with JIA is a flexion contracture, which should be measured with a goniometer (Fig. 15–28). Bony overgrowth at the knee may occur with JIA because of epiphyseal overgrowth in the affected knee and may contribute to a leg-length discrepancy. Posterior subluxation of the tibia is demonstrable when the knee is bent to 90° and the proximal tibia sags posteriorly. This condition is an uncommon complication of JIA. Some children, including those with generalized ligamentous laxity, may have genu recurvatum (hyperextensible knees).

FIGURE 15–28 A child with juvenile idiopathic arthritis and flexion contractures of the knees. The degree of contracture should be measured with the goniometer at each visit.

Inspect the knee for angulation, which is often seen in growing children. A line drawn from the midpoint of the inguinal ligament to the midpoint of the ankle should cross the center of the patella. Genu varus (bowleg or nonrachitic leg bowing) is physiologic in infancy, when the tibiofemoral angle is less than 15° varus and the deformity is symmetric. At roughly age 18 months, the child’s legs appear straight and, by ages 2 to 4 years, the tibiofemoral angle changes to valgus. With increasing age, the valgus gradually reduces to the slight valgus of the normal adult.

Ignore knock knees in a child younger than age 7, unless the valgus is greater than 15° or there is evidence of asymmetry. Asymmetric angular deformity or evidence of knee instability with a lateral thrust (bowleg) or medial thrust (knock knee) that occurs immediately on weight-bearing is not seen in physiologic bowleg or knock knee. Such a finding indicates an underlying pathologic condition, such as Blount disease, rickets, or a growth plate injury.

After inspecting the knee, palpate for a joint effusion using several techniques. Elicit the bulge sign to detect a small to moderate effusion by milking fluid out of the medial recess into the suprapatellar pouch and then stroking the lateral recess in a downward direction to move the fluid back into the medial recess; the latter maneuver creates a fluid bulge in the knee’s medial aspect between the patella and femur.

To demonstrate a large knee effusion, use the patellar tap, as follows: Empty fluid from the suprapatellar pouch by pressing firmly on the suprapatellar pouch with one hand; then use the other hand to tap the patella against the femur. The presence of a palpable tap indicates a large effusion. This is a less sensitive maneuver than the bulge sign and is not always specific. Occasionally, a child with a knee effusion may also have a popliteal cyst (Baker cyst), best detected when the patient lies prone or stands upright. Most Baker cysts disappear spontaneously. They require no treatment when asymptomatic but may rupture spontaneously, causing acute calf pain and swelling that may be confused with a deep vein thrombosis.

Palpate the knee for joint line tenderness with the knee flexed to 90°. Tenderness along the entire joint line suggests synovitis and may be associated with thickened synovium that obscures the normal bony landmarks. Tenderness localized to the medial or lateral aspects of the joint line may suggest a meniscal tear in an older child. Perform a McMurray test by holding the child’s heel in one hand while holding your other hand over the patient’s flexed knee. Rotate the tibia externally and internally over the femur while slowly extending the child’s knee; a palpable or audible clunk or click, sometimes associated with pain, may be detected with a meniscal tear.

Palpate the insertion of the patellar tendon into the tibial tuberosity for evidence of tenderness, warmth, or swelling. Such findings in only one tibial tuberosity suggest Osgood-Schlatter disease. If both are affected, particularly if there is tenderness at the sites of insertion of other tendons or ligaments, suspect enthesitis, an inflammation at the point of insertion of a tendon, ligament, or capsule into bone, commonly seen in children with enthesitis-related arthritis.

A child should be able to flex the knee enough for the heel to touch the buttock, an angle of 130° to 150°. An older child’s flexion may be limited by the calf muscle bulk and by the hamstrings. When the knee is extended, the child should be able to achieve a straight leg; often children have 5° to 10° of hyperextension. Note any crepitation during knee flexion and extension. Crepitation may occur with osteochondritis dissecans, which may be accompanied by tenderness of the affected femoral condyle or with patellofemoral problems with patellar tenderness.

Test the medial and lateral collateral ligaments by stressing them both with the knee extended and flexed approximately to 20°. The ligaments are tight when the knee is in full extension, and no movement should be possible. Slight movement occurs normally when the knee is flexed to 20°, but such movement is painless and limited.

Assess the cruciate ligaments, which normally prevent anterior and posterior instability of the knee and limit medial rotation, as follows: With the knee flexed to 90°, pull the upper tibia forward to test the anterior cruciate ligament; pull the upper tibia backward to test the posterior cruciate ligament. Contracted hamstring muscles can prevent the tibia from moving forward even if there is a complete disruption of the anterior cruciate ligament; therefore, first ensure that the hamstring muscles are relaxed. Normally, there is little movement with this maneuver.

Evaluate patellar pain with the following additional tests:

Ankle and foot examination

Inspect the ankle and foot for swelling, redness, trauma including the presence of a foreign body, and evidence of deformity, such as a clubfoot, pes cavus (high arch), or pes planus (flatfoot). If you find a pes cavus deformity, you must exclude underlying neurological conditions such as spinal dysraphism, Charcot-Marie-Tooth disease, and Friedreich ataxia. In pes planus, or flatfoot, the feet characteristically have a flattened longitudinal arch, valgus hindfoot, and abduction of the midfoot and forefoot (see earlier discussion).

Palpate the foot and ankle to localize areas of tenderness or swelling that may occur secondary to injury. Ankle injuries are common, but only 12% to 15% result in fractures. The Ottawa Ankle Rules may help you determine the likelihood of a fracture and the need for radiographs. According to these rules, if the child cannot bear weight or has tenderness at the posterior edge or tip of the malleolus, a fracture is likely and a radiograph should be obtained. Localized tenderness and swelling of the foot may also occur with stress fractures (particularly at the second metatarsal) or an ingrown toenail. Pain, tenderness, and swelling over the navicular with a limp and a tendency to walk on the lateral edge of the foot suggest Köhler disease (avascular necrosis of the navicular).

After palpating the joints and bony structures of the feet, palpate the Achilles tendon for tenderness because tendonitis may occur from overuse. Tenderness at the points of attachment of the Achilles tendon and of the plantar fascia to the calcaneus also occurs with enthesitis.

Test the range of movement at the three major joints of the foot and ankle. These movements include the following:

Limited movement at the ankle or foot may be caused not only by joint inflammation but also by tarsal coalition, a bony or cartilaginous bridge between tarsal bones that typically causes a rigid flat foot with limited painful motion at the subtalar joint. Confirm this diagnosis with an oblique radiograph of the foot.

Lateral compression of the metatarsals is a good screening test for inflammation of the metatarsophalangeal (MTP) joints. Perform this maneuver extremely gently because it can cause intense pain if one or more MTP joints are inflamed (Fig. 15–29). If the child complains of pain on compression, examine the MTP joints individually to identify the affected joint. Examine the toes for swelling or deformity. Diffuse swelling of a toe that gives it a sausage-like appearance, termed dactylitis, may occur with infection, psoriasis, and Reiter syndrome. Common toe deformities include hallux valgus, syndactyly (webbing deformity), polydactyly, and overlapping fifth toe.

FIGURE 15–29 Screening for inflammation of the metatarsophalangeal joints with the metatarsal compression test. The response “Ouch” constitutes a positive result.

Muscle assessment

Muscle assessment includes inspection of muscle bulk for wasting. Synovitis results in reflex inhibition of muscles acting across a joint, leading to wasting, which may be noticed as early as within 1 week. Widespread wasting of muscles around a joint tends to occur with arthritis, whereas localized muscle wasting is more characteristic of a local mechanical or peripheral nerve problem.

Muscle power is very important to assess. If you have followed the examination procedure described in the chapter, you have already screened muscle power when observing the child’s gait and with a number of maneuvers described in the observation section of the physical examination—hopping, toe-walking and heel-walking, and checking for Gower sign. To assess trunk and neck flexor strength in a child old enough to cooperate, ask him or her to perform five sit-ups and then, while lying supine, to hold his or her head above the pillow for 60 seconds.

You can make a more formal assessment of power performed by using a simple grading scale, shown in Table 15–3. Keep in mind, however, that there is considerable individual variability among both patients and examiners, and strength assessments that use this scale are estimations. Further description of the assessment of muscle power can be found in Chapter 13.

TABLE 15–3 Scale for Grading Muscle Strength

From Cassidy JT, Petty RE: Textbook of Pediatric Rheumatology, 4th ed. Philadelphia, WB Saunders, 2001.