Module 4
Module 4: Abdomen, Genitourinary, & Musculoskeletal
Master abdominal exam, hip screening, and musculoskeletal assessment
Welcome to Module 4!
In this module, you’ll develop critical skills for examining the abdomen, genitourinary system, and musculoskeletal system in newborns. These examinations are essential for identifying congenital anomalies, developmental dysplasia of the hip, and structural abnormalities. We’ll progress from abdominal assessment through specialized hip screening maneuvers to systematic extremity and spine examination.
Learning Objectives
By the end of this module, you will be able to:
- ✅ Systematically examine the newborn abdomen and identify masses, organomegaly, and umbilical findings
- ✅ Assess the genitourinary system and recognize anomalies
- ✅ Perform hip dysplasia screening using Ortolani and Barlow maneuvers
- ✅ Identify risk factors for developmental dysplasia of the hip
- ✅ Examine the spine for integrity and anomalies
- ✅ Differentiate positional deformities from structural abnormalities in extremities
- ✅ Recognize when referral for orthopedic evaluation is needed
Lesson 1: Abdominal Examination
Technique and Approach
The newborn abdominal examination requires gentle, systematic palpation. The infant’s compliance is improved when they are calm and fed (not immediately after feeding to avoid regurgitation).
Positioning:
- Infant supine, legs slightly flexed (to relax abdominal muscles)
- Warm hands before palpation
- Watch face for signs of discomfort
Sequence:
- Inspection for shape, color, distension, visible peristalsis
- Auscultation for bowel sounds
- Palpation (superficial, then deep)
- Assessment of liver, spleen, kidneys
- Umbilical cord examination
Inspection
Normal Findings:
- Abdomen slightly rounded but not distended
- Symmetrical
- Few visible veins
- Active bowel sounds present (clicks and gurgles)
- Umbilical cord with two arteries and one vein
- Cord clamp in place; cord begins to dry and blacken
Abnormal Findings:
- Significant distension or rigidity
- Visible loops of bowel (concern for gastroschisis or other defect)
- Asymmetry or localizing bulge
- Scaphoid appearance (suggests diaphragmatic hernia)
- Shiny, taut skin (peritonitis)
Palpation
Liver Palpation:
- Normally palpable 1-2 cm below right costal margin
- Smooth, firm edge
- Soft, non-tender
- Progressive descent in first days of life as infant transitions
Spleen:
- Tip may be palpable 1-2 cm below left costal margin in newborns
- More easily palpable than in older children
- Firm, non-tender
Kidneys:
- Difficult to palpate in most newborns
- If easily palpable, consider enlargement (hydronephrosis, cystic disease)
Suprapubic Palpation:
- Rule out bladder distension
- Normal newborn bladder palpable initially; should empty with first voids
Abdominal Masses
Diagnosis and Management:
Abdominal Wall Masses:
Umbilical Granuloma
- Pink, granular tissue at umbilical stump
- Drains serous fluid
- Benign, self-limiting
- Treatment: observation, topical silver nitrate or alcohol if excessive drainage
- Does not require surgical intervention
Abdominal Masses - Internal:
Hydronephrosis
- Most common abdominal mass in newborns
- Smooth, flank mass on affected side
- Diagnosis: prenatal ultrasound or postnatal ultrasound
- Management: renal ultrasound within first week, urology referral if significant
Cystic Masses
- Mesenteric cyst, choledochal cyst
- Surgical consultation needed
- Imaging: ultrasound, possibly MRI
Solid Masses
- Neuroblastoma, Wilms tumor (rare in newborns)
- Any solid abdominal mass requires urgent imaging and oncology consultation
- May be detected on prenatal ultrasound
Umbilical Cord Examination
Normal Cord:
- Three vessels: two thick arteries, one thin vein
- Gelatinous substance (Wharton’s jelly) surrounds vessels
- Cord dries and shrivels, falls off by 7-14 days
Umbilical Abnormalities:
Single Umbilical Artery (SUA)
- Finding: Only two vessels present (one artery, one vein)
- Associated with: IUGR, renal anomalies, chromosomal abnormalities
- Management: Renal and cardiac ultrasound, genetic evaluation if other anomalies present
- Isolated SUA: Usually has good prognosis but warrants screening
Cord Prolapse/Herniation
- Emergency requiring immediate delivery if diagnosed prenatally
- Visible at birth: needs immediate surgical evaluation
Omphalocele
- Defect in abdominal wall fascia
- Contents: Bowel, liver covered by peritoneal sac
- Management: Surgical repair, often staged
- Associated with: Genetic syndromes, cardiac anomalies
Gastroschisis
- Defect to the right of midline (unlike omphalocele which is midline)
- No covering membrane
- Contents exposed
- Management: Surgical repair, typically staged
- Associated with: Bowel atresia, other anomalies
Umbilical Stump Care and Complications
Normal Cord Separation:
- Occurs at 7-14 days
- Slight oozing and odor normal during separation
- Keep clean and dry
Cord Complications:
Omphalitis (Umbilical Infection)
- Signs: Erythema, warmth, purulent drainage, foul odor
- Urgent evaluation: Blood culture, CBC, CRP/procalcitonin
- Treatment: IV antibiotics (ampicillin + gentamicin or cephalosporin)
- Risk factor for sepsis
Umbilical Granuloma
- Benign, self-limiting
- Persists after cord falls off
- Pink, moist nodule with serous drainage
- Treatment: Observation, topical silver nitrate, or cautery
Umbilical Hernia
- Small fascial defect at umbilical ring
- Bulges with crying/straining
- Very common in African American and preterm infants
- Management: Observation; most close by age 2-5 years
- Surgery if: >1.5 cm at 5 years, causing pain, or complicated
Inguinal Hernia Examination
Palpation Technique:
- Palpate along inguinal ligament with infant calm
- May feel impulse with crying or straining
- Attempt to reduce gently
Findings:
- Bulge in inguinal region with crying/straining
- Reducible or occasionally irreducible
- Much more common on right side
- More common in preterm and male infants
Management:
- Refer to surgery if: Irreducible (high risk of incarceration), symptomatic, or if parents desire repair
- Can be elective repair but early referral (first weeks) is recommended
- Incarceration risk is high in first year of life
Genitourinary Examination
Male Examination:
Penis
- Assess for: Normal urethral opening at tip
- Hypospadias: Urethral opening on ventral surface
- Epispadias: Urethral opening on dorsal surface
- Curvature: May be present with hypospadias/epispadias
Testes
- Palpate bilateral inguinal canals and scrotum
- Normal: Descended testes (palpable in scrotum or inguinal canal)
- Cryptorchidism: Undescended testicle
- May be retractile in newborn period (normal if can pull into scrotum)
Foreskin
- Normally adherent to glans (non-retractable)
- Separation is normal process; don’t force retraction
- Phimosis (tight foreskin) is normal; only concerning if urinary obstruction
- Circumcision: Defer until cord falls off, infant stable, and parents consent
Female Examination:
Labia and Clitoris
- Assess for: Size, color, swelling
- Clitoral prominence: Can be normal but consider virilization if enlarged
- Assess for proper urethral and vaginal openings
Vaginal Findings
- Vaginal mucus or slight blood-tinged discharge: Normal (maternal hormones)
- Vaginal opening: Should be patent
- Hymenal tissue: May be prominent; normal finding
- Hymenal tags: Small epithelial projections; benign, resolve spontaneously
Imperforate Hymen
- Complete hymenal obstruction
- Usually asymptomatic in newborn
- Requires gynecology referral for management in infancy
Lesson 2: Hip Examination and Developmental Dysplasia Screening
Overview of Developmental Dysplasia of the Hip (DDH)
Developmental dysplasia of the hip affects 1-3 of 1000 live births. Early detection and treatment prevent significant morbidity (limping, arthritis, pain in adulthood). Physical examination screening is crucial in the newborn period when treatment is most effective.
Risk Factors:
- Female sex
- First-born
- Positive family history
- Breech presentation
- Associated conditions: Oligohydramnios, intrauterine constraint
- Certain ethnicities (Navajo, Inuit, Northern European higher risk)
Anatomy Review
The hip is a ball-and-socket joint:
- Femoral head (ball) - articulates with
- Acetabulum (socket) - on pelvis
In DDH:
- Femoral head is incompletely seated in acetabulum
- Can be dysplastic (shallow socket), dislocated (out of socket), or dislocatable
- Goal of early treatment: Maintain reduction while acetabulum develops
Ortolani Maneuver
Purpose: Detect if hip can be reduced from dislocated position (positive = hip was OUT)
Technique:
- Infant supine on firm surface
- Hip and knee flexed to 90 degrees
- Abduct hip (move femur away from midline) while lifting femoral head anteriorly
- Listen and feel for “clunk” as head reduces into socket
- Clunk is palpable (not just audible)
Positive Finding:
- Sudden clunk as femoral head reduces into acetabulum
- This indicates the hip was dislocated and has been reduced
- High sensitivity for dislocated hips
Important Notes:
- Clunk must occur with hip abduction (moving it laterally)
- It’s a distinctive palpable/audible sensation - not subtle
- Most reliable early in life (becomes less sensitive after 6-8 weeks)
- May be impossible to perform if hip in spasm from protective muscle contraction
Barlow Maneuver
Purpose: Detect if hip can be dislocated from reduced position (positive = hip can be PUSHED OUT)
Technique:
- Infant supine, hip and knee flexed 90 degrees
- Abduction: Move knee toward floor while internally rotating femur
- Press distal femur posteriorly with thumb
- Feel for “clunk” as femoral head dislocates posteriorly
- Reverse maneuver to reduce hip
Positive Finding:
- Clunk as femoral head dislocates posteriorly from socket
- This indicates the hip was in socket but dislocatable
- Indicates instability even if currently reduced
Important Notes:
- Applied gently - not a forceful maneuver
- Differentiate from “click” which can be benign (ligament snap, patellofemoral crepitus)
- Clunk is distinctive palpable sensation
- Must feel distinct displacement of femoral head
Abduction Assessment
Normal Finding:
- Hips abduct symmetrically
- Can nearly touch knees to examination table in flexed position
- At least 80 degrees of abduction bilaterally
Abnormal Finding:
- Limited abduction (less than 60-70 degrees on one side)
- Asymmetric abduction
- “Hip click” of abduction: Palpable click/snap at end of abduction range
- May indicate dysplasia or contracture from dislocated hip
- Positive Barlow/Ortolani should prompt further evaluation
Additional Exam Findings Suggesting DDH
Thigh Asymmetry:
- Asymmetric gluteal folds
- Asymmetric thigh skin folds
- Indicates possible muscle contracture from dislocation
Leg Length Discrepancy:
- Relative shortening of affected leg
- Can assess by flexing both hips to 90 degrees (Allis test/Galeazzi sign)
- Affected limb appears shorter
Telescoping:
- Excessive motion along axis of femur
- Indicates severe dysplasia or dislocation
Management Based on Findings
Normal Exam:
- No risk factors: Standard follow-up (no screening ultrasound needed)
- Risk factors present: Consider ultrasound at 4-6 weeks
Positive Ortolani/Barlow:
- Ultrasound of hips within 1-2 weeks
- Orthopedic consultation for management
- May require: Abduction brace (Pavlik harness, Frejka pillow), casting, or surgery
Limited Abduction, Click on Abduction, or Asymmetry:
- Hip ultrasound
- May warrant orthopedic referral based on ultrasound findings
Breech Presentation or High Risk:
- Hip ultrasound at 4-6 weeks
- Earlier ultrasound if clinical concern
Timing of Hip Screening
- Newborn period (birth to 2 weeks): Physical examination screening
- 4-6 weeks: Ultrasound for infants with risk factors or equivocal exams
- After 3 months: Radiographs may become more useful (ossification begins)
- After 8 weeks: Physical exam becomes less sensitive; ultrasound/imaging essential
Lesson 3: Spine and Extremity Examination
Spine Examination
Inspection:
- Examine infant prone (or on side if not cooperative)
- Assess: Midline structures, skin dimples/pits, hair patches, hemangiomas
- Palpate along entire spine from cervical to sacral region
- Assess for: Step-offs, abnormal curvature, masses
Normal Findings:
- Straight spine
- Midline structures aligned
- No masses
- Mobility present
Abnormal Findings:
Sacral Dimple
- Small dimple at sacrococcygeal region
- Very common (up to 2-4% of population)
- Usually benign, located at sacral level
- Management: If simple dimple without other anomalies, reassurance
- Concern: Deep dimple, dimple with hair/halo, or associated with asymmetric gluteal folds warrants ultrasound to rule out tethered cord
Sacral Pit
- Hair-covered or with halo of hyperpigmentation
- Requires imaging (ultrasound or MRI) to rule out tethering
Hairy Patch
- Hair over lumbosacral spine
- May indicate cutaneous marker for underlying dysraphism
- Imaging warranted
Visible Spinal Dysraphism
- Visible opening, asymmetry, or mound
- Requires urgent imaging and neurosurgery consultation
Scoliosis
- Lateral curvature of spine
- Significant curvosis in newborn is rare but concerning
- Requires imaging and orthopedic/neurosurgery consultation
Extremity Examination
General Approach:
- Inspect all four extremities for symmetry, color, swelling
- Palpate for: Fractures, dislocations, masses
- Assess passive range of motion
- Check for: Digit abnormalities, skin findings
- Assess tone and movement bilaterally
Upper Extremity Assessment
Clavicle:
- Palpate bilaterally for: Fractures (crepitus, swelling)
- Clavicular fracture: Common with shoulder dystocia or difficult delivery
- Usually benign, rarely requires intervention
- Healing occurs quickly; gentle handling sufficient
Brachial Plexus Injury:
- Presentation: Flaccid arm, absent Moro on affected side
- Erb palsy (C5-C6): Arm adducted, internally rotated - “waiter’s tip”
- Klumpke palsy (C8-T1): Hand with claw appearance
- Prognosis: Most improve spontaneously; severe cases may need PT/surgery
- Referral to neurosurgery if persistent beyond 3-6 months
Hands:
Polydactyly (Extra Digits)
- Preaxial (thumb side): Usually associated with genetic syndromes
- Postaxial (pinky side): More common in African Americans, often familial
- Postaxial polydactyly can be ligated if soft tissue attachment only
- If bony attachment: Surgical removal needed
Syndactyly (Webbed Digits)
- Simple: Skin webbing only
- Complex: Shared bones or other tissues
- Management: Most don’t require intervention immediately; referral to hand surgery for planning
- May be associated with genetic syndromes
Oligodactyly (Missing Digits)
- Assess: Number, structure of remaining digits
- Function: Assess grasping and movement
- May be associated with genetic syndromes or limb dysgenesis
Lower Extremity Assessment
Femur/Tibia Fractures:
- May occur with difficult delivery (breech extraction, shoulder dystocia)
- Presentation: Swelling, crepitus, pain with movement, reluctance to move limb
- Management: Immobilization (papoose wrap), orthopedic consultation
- Most heal well with conservative management
Metatarsus Adductus:
- Forefoot curves inward (toward midline)
- Medial forefoot deviation
- Very common, often positional
- Flexible vs rigid deformity: Flexibility indicates likely benign course
- Management: If flexible, observation; if rigid, may need orthopedic evaluation
Talipes Equinovarus (Clubfoot):
- Foot is inverted, adducted, and plantarflexed
- Rigid positioning (not easily passively corrected)
- Relatively common congenital anomaly
- Associated conditions: Genetic syndromes, neuromuscular disorders
- Management: Immediate orthopedic referral for serial casting and possible surgery
Positional Deformities vs Structural Abnormalities:
Positional Talipes
- Foot appears deformed but has flexible range of motion
- Foot can be passively corrected to normal position
- Typically improves with positioning and exercise
- Prognosis: Excellent with parent education
Structural Clubfoot (Talipes Equinovarus)
- Rigid, cannot be passively corrected to normal
- Often associated with other anomalies
- Requires intervention (casting/surgery)
Tone and Movement Assessment
Normal Newborn Tone:
- Arms: Flexed at elbow, fist often clenched
- Legs: Flexed at hip and knee
- Some resistance to passive extension (flexor tone predominance)
- Symmetric movements
Hypotonia (Floppy Baby):
- Decreased resistance to passive movement
- Poor head control
- “Rag doll” appearance
- Differential: Sepsis, hypoglycemia, intracranial hemorrhage, congenital neuromuscular disorders, Down syndrome
- Requires urgent evaluation: Labs (glucose, CBC, blood culture), imaging (head ultrasound), possible specialists (neurology)
Hypertonia (Stiff Baby):
- Increased resistance to passive movement
- Rigid appearance
- Differential: Intracranial hemorrhage, infection (meningitis), drug withdrawal, congenital hypertonia
- Requires urgent evaluation
Asymmetric Movement:
- One limb moved less than others
- Differential: Brachial plexus injury, fracture, spinal cord injury, stroke, hemiplegic cerebral palsy
- Requires neuroimaging and specialist evaluation
Clinical Pearls
- Benign positional deformities are common and usually improve with positioning and parental guidance
- “Fisting” of hands is normal; inability to open hand with stimulation concerning
- Metatarsus adductus and positional talipes have excellent prognosis with observation
- Ortolani/Barlow become less reliable after 6-8 weeks; imaging becomes essential
- Always examine unclothed to fully assess all structures
- Compare sides - asymmetry is more concerning than symmetric findings
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Exercise 4.1: Abdominal Exam - Umbilicus, Hernias, and Masses
Let’s practice identifying common abdominal findings in newborns.
Exercise 4.1: Abdominal Exam - Umbilicus, Hernias, and Masses
Your Challenge
Examine images showing various abdominal findings in newborns. Assess each finding by identifying what you see, determining if it's benign or concerning, recognizing when surgical consultation is needed, understanding the expected course, and providing appropriate parent education.
View Clinical Cases
Exercise 4.2: Hip Exam and Developmental Dysplasia Screening
Practice performing hip screening and recognizing risk factors for developmental dysplasia.
Exercise 4.2: Hip Exam and Developmental Dysplasia Screening
Your Challenge
Review clinical cases with hip examination findings. Describe proper examination technique, identify positive versus negative findings, recognize DDH risk factors, and determine the need for ultrasound or orthopedic referral.
View Hip Examination Cases
Exercise 4.3: Extremity and Spine Examination
Develop skills in differentiating normal variations from abnormal findings.
Exercise 4.3: Extremity and Spine Examination
Your Challenge
Review images and descriptions of extremity and spine findings. Assess each finding by differentiating normal variations from true abnormalities, examining spine integrity and cutaneous markers, assessing digit abnormalities, and determining need for further evaluation or referral.
View Extremity and Spine Cases
Module 4 Complete!
Congratulations on completing Module 4! You’ve developed essential skills in abdominal, genitourinary, and musculoskeletal examination:
Identifying common abdominal findings and masses Recognizing umbilical anomalies and their management Performing and interpreting hip dysplasia screening maneuvers Differentiating DDH risk factors and determining imaging needs Examining the spine and recognizing cutaneous markers Distinguishing positional deformities from structural abnormalities Knowing when specialist referral is needed
Key Takeaways
-
Ortolani vs Barlow - Ortolani detects reduction of dislocated hip; Barlow detects dislocatability. Both are palpable clunks, not subtle findings.
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DDH Screening Timeline - Most sensitive in newborn period (before 6-8 weeks); ultrasound becomes more important for screening and diagnosis after 4-6 weeks.
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Risk Factors Matter - Female, firstborn, breech presentation, and family history increase DDH risk and should prompt ultrasound even with normal exam.
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Umbilical Findings Vary Widely - From completely benign (cord care, separation) to urgent (gastroschisis, omphalocele). Know which need immediate surgical consultation.
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Positional vs Structural - Positional deformities are flexible and improve with parental positioning/exercise. Structural abnormalities require specialist intervention.
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Cutaneous Markers Matter - Simple sacral dimple is usually benign, but hairy patches, deep pits, or associated asymmetry warrant imaging to rule out spinal dysraphism.
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Digit Abnormalities Assessment - Polydactyly/syndactyly require evaluation for associated syndromes. Isolated postaxial polydactyly has better prognosis than preaxial.
Critical Safety Points
RED FLAGS requiring urgent action:
- Any gastroschisis or omphalocele - immediate surgical consultation
- Positive Ortolani/Barlow in newborn - orthopedic referral and imaging
- Rigid clubfoot - cannot be passively corrected - urgent orthopedic referral
- Signs of hypotonia/hypertonia - urgent evaluation for intracranial pathology or infection
- Visible spinal dysraphism - urgent neurosurgery consultation
- Brachial plexus injury (Erb/Klumpke) - early rehabilitation important
- Sacral dimple with concerning features - imaging to rule out tethered cord
What’s Next?
In Module 5, you’ll complete your comprehensive newborn assessment with examination of the skin and neurological system. You’ll practice identifying benign newborn rashes versus concerning conditions, assessing primitive reflexes, and performing a complete neurological exam.