Acute Limp

Question 1

What is antalgic gait

Answer 1

Shortening of the stance phase and prolonging of the swing phase, as the child ‘hurries’ off one leg to offload the source of pain (most common, usually trauma or infection)

Question 2

What is trendelenburg gait

Answer 2

pelvis exhibits a downward tilt towards the unaffected side during the swing phase due to weakness in the contralateral gluteus medius muscle (DDH, Perthes’ disease, SCFE)

Question 3

What is steppage gait

Answer 3

excessive flexion of the hip and knee joints during the swing phase due to an inability to dorsiflex the foot (Cerebral palsy, neurological disorders)

Question 4

What is vaulting/circumduction gait

Answer 4

hyperextension and locking of the knees at the end of the stance phase and the child vaults over the extremity (limb-length discrepancy, mechanical disorder causing abnormal knee mobility)

Question 5

What are the causes of acute limp

Answer 5

Transient synovitis
DDH
Fracture
Infection – septic arthritis, osteomyelitis of hip or spine
Overuse injuries
Perthes disease (acute)
Juvenile idiopathic arthritis (JIA)
Osteochondritis dissecans of the knee
Trauma – accidental/non-accidental
Malignant disease – leukaemia, neuroblastoma, bone tumours

Question 6

What are the causes of chronic limp

Answer 6

DDH
Talipes
Neuromuscular, e.g. cerebral palsy
Juvenile idiopathic arthritis (JIA)
Tarsal coalition
Slipped capital femoral epiphyses

Question 7

What features suggest an organic cause of limp

Answer 7

Occurs day and night
Interrupts play
Pain located in the joint, unilateral
Weight loss, fever, nights sweats
Rash
Diarrhoea
Point tenderness
Redness
Swelling
Limited movement
muscle weakness of atrophy
Lymphadenopathy

Question 8

What features suggest a non-organic cause of limp

Answer 8

Only occurs at night, primarily on school days
No interference with normal activities
Located between joints bilateral
Otherwise healthy

Question 9

What are the red flags for urgent referral to paeds for a limp

Answer 9

<3yo
>9yo with painful or restricted hip movements (internal rotation esp.)
Unable to weight bear
Fever and/or signs: pain causing night-waking, fatigue, anorexia, weight loss, night sweats
Severe pain, agitated, reduced peripheral pulses
Muscle weakness/sensory impairment
Suspicion of NAI

Question 10

What investigations should be done for a limp

Answer 10

Bloods: FBC, plasma viscosity, ESR/CRP, muscle enzymes
Other
- X-ray of affected joint
- Bone scan

Question 11

What is transient synovitis and its epidemiology

Answer 11

Acute hip pain associated with a viral infection
2-12yo
Most common cause of acute pain in children

Question 12

What are the signs and symptoms of transient synovitis

Answer 12

Preceding viral illness

Sudden onset pain in the hip or a limp (may refer to knee)
No pain at rest
Decreased range of movement, particularly internal rotation
Mild fever or afebrile BUT does not appear ill

Question 13

What is the management for transient synovitis

Answer 13

Any limp + fever → urgent specialist assessment

Once diagnosed: self-limiting
Bed rest
Pain relief e.g. paracetamol, ibuprofen
resolves after a few days (refer if >1 week)

Question 14

What is Kocher’s criteria

Answer 14

indicates septic arthritis over transient arthritis:
Temperature > 38.5oC
Refusal to weight bear on affected limb
Raised inflammatory markers à ESR > 40mm/hour, CRP > 20mg/L
WCC > 12 x 109/L

Question 15

Describe growing pains

Answer 15

Organic disease has been excluded
May be caused by oedema in the fascial sheaths
3-6yo
Pain at night, often after a day of vigorous activity
headaches and abdominal pain may also be experienced
Should NOT cause a limp

Question 16

What could Nocturnal wakening with leg pain indicate and what are the other features

Answer 16

Growing pains (normal)
Osteoid osteoma (normal)

+ anaemia, bruising, irritability, infections: leukaemia, lymphoma, neuroblastoma

Question 17

What could a clunk on hip movement in neonates indicate and what are the other features

Answer 17

DDH (older infant, asymmetrical upper leg skin folds, limited hip abduction)

Question 18

What could febrile, toxic-looking infant with irritability on nappy changing with joint pain suggest and what are the other features

Answer 18

Septic arthritis (raised WCC/CRP/ESR)
Osteomyelitis

Both show restricted joint range (esp. hip) or limb movement

Question 19

What could Sudden limp in an otherwise well child indicate and what are the other features

Answer 19

Transient synovitis
Perthes disease

Both may show unilateral restricted hip movement

Question 20

What could Fever, erythematous rash, red eyes, irritability in infant/young child with a limp indicate and what are the other features

Answer 20

Kawasaki disease (erythema/oedema of hands and feet, oral mucositis, cervical lymphadenopathy)

Question 21

What could irritability, fever and reluctance to move in an infant/young child with limp indicate and what are the other features

Answer 21

Discitis (stiff back, tripod sitting)
Vertebral osteomyelitis

Question 22

What could hip pain in adolescent boys indicate and what are the other features

Answer 22

SUFE (unilateral hip restriction)

Question 23

What could Lethargy, unwillingness to do physical activity, irritability and rash indicate in children with a limp and what are the other features

Answer 23

Juvenile dermatomyositis (eyelid erythema, proximal muscle weakness

Question 24

What could lethargy, arthralgia, constitutional symptoms with limp indicate and what are the other features

Answer 24

Juvenile onset SLE (multisystem abnormalities, haematuria, facial erythema)