The Limping Child

Wendalyn King MD, MPH

Walking

2 phasesStance Swing

Both feet in contact with ground only 20% of gait cycle

Developmental processToddlers – short, rapid stepsAdult gait pattern present around age 3

Limp

Antalgic gait Pain leads to shortened stance phase on affected side Most common acute presentation of limp

Trendelenberg Underlying proximal muscle weakness or hip instability Equal stance phase, but trunk shifts over affected

extremity Usually non-painful “waddling” gait if bilateral process

Differential Diagnosis Trauma

Acute Repetitive

SCFE, AVN

Infectious/inflammatory Septic arthritis Inflammatory arthritis Osteomyelitis Diskitis

Neoplastic Leukemia Primary and

metastatic bone lesions

By Age

Toddler (1-3yr) Infection Occult trauma Neoplasia

Child (4-10) Infection Transient synovitis LCPD / AVN Rheumatologic disorder Trauma Neoplasm

Adolescent (11+) SCFE Rheumatologic

disorder Trauma

Evaluation

HistoryOnset of symptomsFever, systemic symptomsHistory of trauma

Often present, may be misleading

Physical examination Inspection Observe gaitRange of motion (feet, knees, hips)

Evaluation

Xray Labs

CBC, ESR, CRP may be helpful in some instances

Other imagingUltrasound (hips)CT /MRIBone scan

Case #1

18 month old with acute onset limp Afebrile, otherwise no complaints Happy and playful until stands up

Fussing, resists weight bearing on R Normal examination

Toddler Fracture

Spiral fracture of distal 1/3 of tibia Usually simple fall while running or stepping on

object May occur up to 6 yr age (peak 2-4yr) May not be visible on normal AP/Lat film

Oblique film Repeat films

Callous formation within 1-2 week

Splint/cast Healing within 3-4 weeks

Case #2

2yo male with 1 week of progressive limp and leg pain

Xray at beginning of symptoms negative Splinted for presumptive fracture Low grade fever, increasing fussiness, now “dragging

leg” and refusing to walk Exam

Fussy, ?tender to palpation distal L leg CRP, ESR elevated

Osteomyelitis

Most common in children <10 Usually hematogenous seeding of bone

Trauma (even minor) may predispose Usually begins in metaphaseal region of long bone Inflammatory exudate collects in marrow, cortex,

subperiosteal space Ischemia leads to infarction and pain Form area of necrotic bone called sequestrum

Eventually separates to form free body or may be reabsorbed

Osteomyelitis

Common organismsStaph aureus most commonGroup B strep in neonatesH. flu, Strep pyogenes, Salmonella,

Pseudomonas, Kingella kingae May be difficult to localize

NeonatesSpine, pelvis

Osteomyelitis

Diagnosis Radiographs

May be normal or nonspecific for 10-14 days Bone scan, CT, MRI may be needed

Acute phase reactants WBC normal initially in 60% cases CRP rises in 8 hours, peaks 2 days, normalizes over 1 week ESR normal in 25% new onset cases, may be useful for monitoring

therapy Blood culture positive 50-60% cases Bone aspiration or biopsy Treatment is 3-6 weeks of antibiotic therapy

Case #3

4 year old female with worsening limp and leg pain. Tactile fever at home

Recent URI, otherwise healthy Exam

Uncomfortable, lying in bed, cries when approached

Septic Arthritis

Usually hematogenous seeding Extension of osteomyelitis Direct inoculation into joint from penetrating trauma

Etiology Staph aureus (H. flu historically) Kingella kingae Neonates: E. coli, Candida, GBS Adolescents: N. Gonorrhea

Septic Arthritis

Presentation Acute joint inflammation

Swelling, redness, pain “Pseudoparalysis”

Joint held in position to maximize intra-articular space and minimize pressure and pain

Hip – flexion, abduction, external rotation Knee - partial flexion Shoulder – adduction and internal rotation Elbow – midflexion

Often have fever and ill appearance

Septic Arthritis

Diagnosis Blood culture positive 30-40% Elevated CRP, ESR Arthrocentesis Imaging

Widening of joint space, soft tissue swelling Ultrasound useful for hip effusion

Treatment Antibiotic Irrigation and drainage Prompt surgical drainage of hip (and often shoulder) needed to reduce

intra-articular pressure and avoid avascular necrosis of femoral head

Diagnostic Dilemmas

Transient synovitis of hip (“toxic synovitis”) Non-infectious, inflammatory condition Usually children 3 – 8yrs May follow viral URI Mild fever, limp, fussiness Minimal limitation of range of motion ESR, CRP, WBC usually normal Managed with rest, NSAIDs, close follow up

Diagnostic Dilemmas

Overlying cellulitis vs Septic Arthritis Other causes of acute arthritis

HSPSerum sicknessJRA, lupusTick borne illness

Case #4

4 yo male with 3d h/o limp and thigh pain No fever Some improvement with ibuprofen Active and playful Uncomfortable with rotation of hip

Avascular Necrosis

Legg-Calve-Perthes Disease Usually occurs 2 – 12 yrs (avg 7) Males > female May be secondary to repeated micro-

trauma Recurrent episodes of hip irritability

common

AVN

Risk of later degenerative arthritisWorse prognosis with older age (>10) and

extensive femoral head deformityVery good prognosis in children <5

TreatmentSymptomatic – rest, pain medsObservation for children <6Surgery for older children with severe

involvement

Case #5

5yo female with several days of leg and back pain, decreased appetite and activity and ?weight loss

Xrays pelvis at outside facility negative 2 d before Pt alert, thin, ill and uncomfortable appearing.

Cries with manipulation of hips/legs. ? Firmness to palpation in upper abdomen

CBC, chemistry normal

Neoplastic

Leukemia Neuroblastoma Primary bone tumors

Benign Unicameral bone cyst Osteoid osteoma

Malignant Ewing and osteogenic sarcomas

Spinal tumors

Case #6

12yo male with chief complaint of knee pain

Present for a couple weeks, acutely worsened after playing basketball

No fever, no other symptoms Exam: walks with limp

Knee – no swelling, no tenderness, normal range of motion

Slipped Capital Femoral Epiphysis(SCFE) Most common adolescent hip disorder Type of epiphyseal fracture Common in obese adolescents

(also in tall, thin kids after growth spurt)

May present with chronic limp, acute pain or combination

Hold leg in slight external rotation and have limited internal rotation

SCFE

XrayNeed both hips for comparisonNeed frog-leg radiographEarliest sign is widening of epiphysis

“pre-slip” conditionLine drawn along outer aspect of femoral

neck should intersect the femoral capital epiphysis

Case #7

15 yo male brought in by EMS for sudden onset severe hip and leg pain

Was running 40 yard dash for football tryouts when developed severe pain and difficulty ambulating

Exam: very uncomfortable, pelvis stable but painful to palpation, pain with hip movement, especially hip flexion

Avulsion

Probably secondary to repetitive stress/microfracture

3 common sites (at major muscle insertions) Anterior inferior iliac spine Superior iliac crest Ischial tuberosity

Initial therapy is rest, crutches, pain meds Outpatient orthopedic follow up

Summary

Many causes of acute limpRange from trivial (new shoes) to life

threateningThorough history and physical importantLiberal use of imaging studiesKeep in mind common conditions for each

age groupClose follow up if diagnosis in doubt

Questions???