Pediatric orthopedic physical examination of the musculoskeletal system should include two steps:
- a screening examination
- a complete musculoskeletal evaluation performed to assess a specific complaint.
The history and physical examination provide the diagnosis in most cases. It should be thorough and carefully performed. With the proper approach, it is usually possible to perform an adequate examination even without the cooperation of the infant or child.
Approach the child in a friendly and gentle fashion. Examining the child on the mother’s lap is helpful. If the child is still nervous, keep your distance while obtaining the history. Reassure the child that all you plan to do is to watch her walk or move her legs. If the child is still nervous, examine the parent or sibling first. The child may find it reassuring for you to go through the examination with the parent first. If the child will not cooperate in walking, carry her to the opposite side of the room. The child will usually walk or run back to the parents. If the child has pain, always examine the painful site last.
Examine the adolescent in a gown or, even better, in a swimsuit. It is essential to see the whole child to avoid missing important clues in diagnosis such as a skin dimple that may accompany an underlying spinal deformity.
Perform the screening examination first before focusing on the principal complaint. This screening ensures that you do not miss any other orthopedic problems and will provide an overview of the musculoskeletal system necessary to understand the specific problem. For example, knowledge of the degree of generalized joint laxity is valuable in assessing a flatfoot or a dysplastic hip. A cavus foot deformity is a common feature of diastematomyelia.
Examine the infant on the mother’s lap. First, observe the general body configuration. Next, observe the infant’s spontaneous movement patterns for evidence of paralysis or pseudoparalysis. Any reduction of spontaneous movements is an important finding. For example, the only consistent physical finding of the neonate with septic arthritis of the hip is a reduction in spontaneous movement of the affected limb. Finally, systematically examine the limbs and back for joint motion and deformity. Always perform a screening hip examination to rule out developmental hip dysplasia.
Examining the child and adolescent
The examination requires several steps:
Does the child look sick? With the child standing in the anatomic position, observe her from the front, side, and back. Look at body configuration, symmetry, and proportions and for specific deformities.
Pelvis and back
Place your hands on the iliac crests—are they level? A pelvic tilt usually results from a limb length difference. With the child facing you, assess thoracic and lumbar symmetry for evidence of scoliosis by the forward-bending test. Observe the sagittal alignment of the spine.
Ask the child to walk slowly across the room and back first with normal gait and then repeated on her toes and heels. Observe the gait for evidence of asymmetry, irregularity, or weakness. Any abnormal or questionable findings discovered during the screening examination should prompt a more complete evaluation of the problem. For example, a finding of in-toeing should prompt an assessment of the rotational profile.
The history and findings of the screening examination serve as guides to more in-depth evaluation.
Joint laxity Joint mobility is greatest in infancy and declines throughout life. Joint laxity, like other traits, varies widely among individuals and is usually genetically determined. Extremes in joint laxity are seen in certain disorders, such as Ehlers–Danlos syndrom.
Assess joint laxity by testing the mobility of the ankles, knees, elbows, thumbs, and fingers. Excessive laxity in four or all of the five joints tested occurs in about 7% of children. Joint laxity is a contributing factor of hip dysplasia, dislocating patellae, and flatfeet, and it increases the risk of injuries such as sprains. In general, excessive joint laxity suggests the possibility of other problems.
Range of motion (ROM) The normal values of joint motion change with age. Generally, the arc of motion is greatest in infancy and declines with age. Specific joints are affected by intrauterine position. For example, lateral hip rotation is greatest in early infancy and declines during the first 2 or 3 years of growth. In assessing ROM, a knowledge of normal values is helpful. Make certain that the position of the pelvis is determined by palpation when assessing hip abduction.
Contractures of diarthrodial muscles are common in children and sometimes require lengthening. For example, contracture of the gastrocnemius and gracilis occur in cerebral palsy. By proper positioning of the joints above and below the contracture, it is possible to differentiate contractures of these muscles from adjacent elements of the same muscle group.
Hip flexion motion is difficult to measure due to compensatory motion of the lumbar spine. Measure the range of motion by the Thomas or prone extension tests. The prone extension test has been found to be more reliable. ROM measurements of most joints are reproducible within about ±4°.
Deformity is classified as either functional or structural. Functional deformity is secondary to muscle contracture or spasm-producing fixation of a joint in an abnormal position. For example, a fixed hip adductor contracture elevates the pelvis on the affected side, producing a functional shortening of the limb. This deformity is commonly seen in cerebral palsy and Perthes disease. In contrast, structural deformity originates within the limb. An example is the limb shortening associated with fibular hemimelia.
Assess deformity in reference to body planes with the body in the anatomic position. Frontal or coronal plane deformity is most easily observed and creates the most significant cosmetic disability. Sagittal plane deformity produces problems in the plane of motion. Finally, transverse or horizontal plane deformity is most difficult to visualize and had often been overlooked in the past. Currently, CT and MRI studies allow visualization and documentation of this plane and increase the appreciation of transverse plane problems. In assessing and documenting deformity, it is essential that each plane be separated clearly and described independently. For example, in tibia vara, deformity occurs in both the frontal and transverse planes. Failure to clearly separate these planes may result in serious errors if operative correction is undertaken.
Function may be impaired by many mechanisms. The impairment is most obvious when the onset is acute and recent. The parents are aware when the pseudoparalysis is due to their child’s “pulled” or “nursemaid’s” elbow. Conversely, long-standing changes in function may be overlooked or just considered as an unusual characteristic of the child. A child’s bilateral abductor lurch from dislocated hips may go unappreciated for years. Limping of recent origin is usually obvious to the parents. Sometimes the examination is normal, and imaging studies are necessary to establish the diagnosis.
Evaluate altered function of recent onset for evidence of trauma or infection. Look for deformity, swelling, or discoloration. Palpate to determine if tenderness is present. Finally, evaluate joint motion for stiffness or guarding. For example, inflammatory and traumatic hip disorders cause a loss of medial hip rotation and guarding of the joint. Evaluate chronic problems for evidence of deformity and an underlying disease. The chronic problem is much more likely to be serious and require a complete and thorough evaluation.
Functional disability is more significant than deformity. Deformity is static; function is dynamic. Deformity is most significant when it adversely affects function. This concept is becoming more universally accepted with time. In the past, handicapped children with conditions such as cerebral palsy were subjected to endless treatments to correct deformity. Often, deformity was corrected at the expense of function. The net effect was harmful.
Some alteration in function is subtle and not readily apparent. For example, a malunited bone forearm fracture may cause a permanent reduction of forearm rotation in the older child. The child compensates for the deformity by rotating the shoulder and may not be aware of any problem. This loss of motion can be detected by physical examination. Determine the degree of disability by functional tests that focus on activities requiring pronation and supination.
Pain in the child is usually significant. For example, the majority of adults experience back pain, but rarely does it require active treatment. Pain in the adolescent is more likely to have a functional basis, as is so common in adults. Trauma may result from acute injury or from the so-called microtrauma or overuse syndromes. Overuse syndromes account for the majority of sports medicine problems in children and adolescents.
Point of Maximum Tenderness
The most useful test in establishing the cause of pain is determining its anatomic origin by locating the point of maximum tenderness (PMT). Localization of the PMT, together with the history, often establishes the diagnosis. For example, a PMT over the tibial tubercle in a 13-year-old boy very likely means the boy has Osgood–Schlatter disease. A PMT over the anterior aspect of the distal fibula, together with a history of an ankle injury, probably points to an ankle sprain. A PMT over the tarsal navicular in a 12-year-old girl suggests the diagnosis of an accessory ossicle.
The examination to establish the PMT should start distant from the problem. Palpate gently, moving progressively closer to the site of discomfort. Watch the child’s face for signs of discomfort. Often a change in facial expression is more reliable than a verbal response. Be gentle. Ask the child to tell you where the tenderness is greatest. With gentleness, patience, and sensitivity, the PMT can usually be established accurately with minimal discomfort.
The PMT is a useful guide in ordering radiographs. A PMT over the tibial tubercle suggests the diagnosis of Osgood–Schlatter disease. If confirmation is necessary, order a lateral radiograph of the knee. Similarly, order oblique radiographs of the elbow if the PMT is over the lateral condyle. Fracture of the lateral condyle may be demonstrated only on the oblique radiograph.
The PMT is helpful in evaluating the radiographs. For example, locating the PMT aids in differentiating an accessory ossification center from a fracture. Only a fracture will be tender. To determine if a subtle cortical irregularity in the contour of the distal radius represents a buckle fracture, locate the PMT. If the cortical irregularity represents a fracture, the PMT and the questionable radiographic change will coincide exactly in location.
Spondyloarthropathy Seronegative spondyloarthropathies in the incipient stage are associated with a PMT in specific locations. These are referred to as enthesopathies. Common sites include the metatarsal heads, plantar fascia, achilles tendon insertion, greater trochanter, and sacroiliac joints.
Leg Aches Leg aches, or growing pains are discomforts of unknown cause that occur in 15–30% of otherwise normal children. Headaches, stomachaches, and leg aches, in that order, are the common pains of childhood. Leg aches characteristically occur at night, are poorly localized, have a long duration, and produce no limp or apparent disability. Spontaneous resolution occurs, without sequelae, over a period of several years.
Because the pain of leg aches is so diffuse and nondescript, the differential diagnosis includes most painful disorders of childhood. The conditions a physician must rule out include neoplastic disorders such as leukemia, hematologic problems such as sickle cell anemia, infections such as subacute osteomyelitis, and various inflammatory conditions.
Muscle testing is done to determine the strength of muscle groups. Testing is performed for neuromuscular problems such as poliomyelitis and muscular dystrophy. The grades can be further subdivided by a plus or minus designation.