What should be included in a physical exam for a 4-week-old male?

Physical Examination of a 4-Week-Old Male Infant

A comprehensive physical examination of a 4-week-old male should include systematic head-to-toe assessment with particular attention to growth parameters, neurological evaluation, and screening for congenital abnormalities, following the same components recommended for 2-month well-child visits. 1

Growth Parameters and Vital Signs

• Measure and plot weight, length, and head circumference on CDC or WHO growth charts to identify percentiles and detect microcephaly, macrocephaly, or growth impairments 2, 1
• Document temperature, heart rate, respiratory rate, and oxygen saturation 3, 4
• Assess overall appearance, activity level, and interaction with caregivers, as alterations may indicate systemic illness 1, 3

Head and Neurological Examination

• Examine fontanelles for size, tension, and any bulging or depression 1, 3
• Assess head shape for abnormalities or asymmetry 1
• Evaluate tone and posture through ventral suspension - the infant should demonstrate appropriate head control for age 2
• Assess primitive reflexes including Moro, rooting, sucking, and grasp reflexes 2, 1
• Observe spontaneous movements and symmetry of movement patterns 2, 1
• Examine for any involuntary movements or abnormal posturing 1, 5

Eye Examination

• Perform red reflex testing bilaterally to detect cataracts, retinoblastoma, or other ocular media abnormalities 1, 5
• Conduct binocular red reflex (Brückner) test to assess symmetry 1
• Inspect external ocular and periocular structures for abnormalities 1
• Assess pupillary responses to light 1
• Evaluate fixation and following behavior - infants at this age should begin tracking faces 1

Ear, Nose, and Throat

• Examine tympanic membranes for appearance 1, 3
• Assess nares for patency - bilateral choanal atresia can present with respiratory distress 1, 3
• Examine oral cavity including palate integrity (to rule out cleft palate), tongue position, and frenulum 1, 3
• Observe quality of suck and swallow during feeding if possible 2

Cardiovascular and Respiratory System

• Auscultate heart for rate, rhythm, and presence of murmurs - many innocent murmurs present in infancy, but pathologic murmurs require evaluation 1, 3
• Auscultate lungs bilaterally for air entry and any abnormal sounds 1, 3
• Assess respiratory rate and pattern - normal rate is 30-60 breaths per minute at this age 1, 3
• Evaluate perfusion by assessing capillary refill and skin color 1, 3

Abdominal Examination

• Palpate for organomegaly, masses, or tenderness 1, 3
• Examine umbilical cord site for complete healing and absence of infection, discharge, or granuloma 1
• Assess for umbilical hernia 1

Genitourinary Examination

• Examine external genitalia in males: assess for descended testes bilaterally, hypospadias, hydrocele, or inguinal hernia 1, 3
• Observe urinary stream - a weak or dribbling stream may indicate posterior urethral valves 1
• Palpate for inguinal hernias, which are more common in males 1

Musculoskeletal and Hip Examination

• Perform Ortolani and Barlow maneuvers to screen for developmental dysplasia of the hip - this is critical at this age 1, 3
• Assess for hip click, limited abduction, or asymmetric thigh folds 1
• Examine extremities for symmetry, range of motion, and any deformities 3
• Assess muscle bulk and tone in all extremities 2

Skin Examination

• Inspect skin for color, perfusion, jaundice, rashes, or lesions 1, 3
• Examine for birthmarks and document their characteristics 1
• Assess for any signs of injury or bruising - any concerning patterns warrant consideration of non-accidental trauma even at this young age 3

Neuromotor Assessment Specific to Age

• Assess postural tone through ventral suspension - at 4 weeks, the infant should briefly lift head when prone 2, 1
• Observe for symmetry of movement - asymmetry suggests neuromotor dysfunction 2, 5
• Evaluate extremity tone by assessing scarf sign and popliteal angles 2
• Note any persistence of fisting beyond expected age or abnormal hand posturing 2

Developmental and Social Interaction

• Observe for social smiling, which typically emerges around 6-8 weeks but may begin earlier 1
• Assess visual tracking and response to faces 1
• Evaluate alertness and responsiveness to stimuli 1

Special Considerations

• For premature infants, correct for gestational age by subtracting the number of weeks born early from chronological age when assessing developmental milestones and growth 1, 5
• Premature infants born at less than 32 weeks gestation or who have not reached 45 weeks postconceptional age require heightened surveillance 1

Critical Pitfalls to Avoid

• Do not skip hip examination - developmental dysplasia is most treatable when detected early 1, 3
• Always perform red reflex testing - delayed diagnosis of retinoblastoma or cataracts can result in permanent vision loss 1
• Document if vital signs cannot be obtained rather than leaving fields blank 3
• Ensure proper measurement technique for head circumference, as microcephaly or macrocephaly may indicate serious underlying conditions 2