Children’s Orthopaedics – The Limping Child

Question 1

what is a limp?

Answer 1

A limp is an abnormal gait commonly due to pain, weakness or deformity

A common presentation with many causes

Defined as a shorter stance phase (weight-bearing) on the affected limb

It is often, though not always, due to pain

Question 2

what ar ethe different types of limps that may be seen and their causes?

Answer 2

Question 3

what is the Surgical sieve for limps as there are many causes

Answer 3

Question 4

Trimodal age specific causes - what are the cause sof limp in years 0-5

Answer 4

‘Normal variant’

Trauma

Transient synovitis

Osteomyelitis

Septic arthritis

DDH

JIA

Question 5

Trimodal age specific causes - what are the cause sof limp in years 5-10

Answer 5

Trauma

Transient synovitis

Osteomyelitis

Septic arthritis

Perthes disease

Question 6

Trimodal age specific causes - what are the cause sof limp in years 10-15

Answer 6

Trauma

Osteomyelitis

Septic arthritis

SUFE

Chondromalacia

Neoplasm

Question 7

what are important things to aks in the history and what may it look like?

Answer 7

• Duration and progression of limp?
• Recent trauma and mechanism?
• Associated pain and its characteristics?
• Accompanying weakness?
• Time of day when limp is worse?
• Can the child walk or bear weight?
• Has the limp interfered with normal activities?
• Presence of systemic symptoms like fever, weight loss?
• Medical history, —birth history, immunisation history, nutritional history, and developmental history
• Drug history, allergies
• Family history

Question 8

when exmaining a child who should you get information from?

Answer 8

Question 9

what different things need to be done on examination?

Answer 9

• Look:

Check sole of foot for foreign bodies !

Deformity? Erythema? Swelling? Effusion?

limitation of active ROM, asymmetry

Assess shoes for unusual wear on the soles, asymmetry, point of initial foot strike, and also assess the fit

In older children look for scoliosis, midline dimples, and hairy patches, which could indicate spinal pathology

Assess gait with the child barefoot

Assess thigh or calf circumference for asymmetry

Leg length assessment

• Feel & Move - Spine, Hip, Knee, Ankle, Foot
• Neurological assessment

Question 10

If you know about a condition and the presentation, diagnosis can be ____

Answer 10

easy

Question 11

Infection and inflammation
Sometimes it is important to identify & differentiate

what conditions may be hard to tell apart?

Answer 11

• Septic arthritis – infection in joint that causes rapid damage and immediate treatment
• Osteomyelitis – infection in a bone, doesn’t need emergency intervention but neds IV antibiotics
• Transient synovitis – post viral inflammation of joints, diagnosis of exclusion

Question 12

• Septic arthritis
• Osteomyelitis
• Transient synovitis

in a history what do you ask and how do you differentiate between these 3

Answer 12

• Limp (age dependent)
• Pain
• General malaise/ loss of appetite/ listless
• Temperature
• Recent URTI/ ear infections
• Trauma
• Pseudoparalysis – wont move joint
• Listen to the parent, they are usually right

Question 13

• Septic arthritis
• Osteomyelitis
• Transient synovitis

in a examination what do you ask and how do you differentiate between these 3

Answer 13

• Do they look sick?
• Limp?
• Absolute refusal to weight bear? (suggests infection, tumour or facture)
• Localising area- ankle/ tibia/ knee/ thigh/ hip
• Hip - obligatory ER?, which movements hurt?
• Ankle- distal tibia or joint line?
• Knee- joint line or metaphyseal area?
• Upper limb disuse

Question 14

what are some Differential Diagnosis (pre-investigation) of

• Transient synovitis
• Osteomyelitis
• Septic arthritis

Answer 14

• Sarcoma
• Myositis
• Osteoid osteoma
• Abscess
• Inflammatory arthropathy

Question 15

Initial investigations
What are you looking for, which tests to do?

Answer 15

• Temperature
• X-ray?
• USS? - experience of the operator makes a great difference to result, can confirm effusion of joint as not apparent clinically
• Bloods - WCC, CRP, ESR, CK, Cultures

Question 16

what is the clinical prediction rules for septic arthritis?

Answer 16

CRP over 30 is significant

Question 17

what is the presentation of septic arthritis?

Answer 17

• Limping
• Pseudoparalysis
• Swollen, red joint
• Refusal to move joint
• Pain
• Temperature

Question 18

whatis the distribuption of septic arthritis in the body?

Answer 18

Question 19

what ar ethe routes of entry in septic arthritis?

Answer 19

Most common way infection gets into a joint is through haematogenous spread, infection got in blood stream then moved to joint

Dissemination form osteomyelitis

Infection often in growth plate as highest blood supply

Question 20

what is the treatment of septic arthritis? (often with surgery)

Answer 20

• Typically Staph. aureus infection
• Aspiration
• Arthroscopy - Knee/shoulder/ankle
• Arthrotomy
• ANTIBIOTICS:
• IV for how long? Empirically 2 weeks
• How long a duration? Traditionally 6 weeks total

Question 21

how do you investigate septic arthritis?

Answer 21

• FBC & differential - Raised WCC >12,000/mm3
• ESR >50mm/hr
• CRP
• Blood cultures - +ve in 30-50%
• Xray
• ULTRASOUND- ALWAYS BE PRESENT
• Synovial fluid - WCC >50,000/mm3, Gram stain, Culture

Question 22

what is osteomyelitis?

Answer 22

Osteomyelitis is an infection in a bone. Infections can reach a bone by traveling through the bloodstream or spreading from nearby tissue. Infections can also begin in the bone itself if an injury exposes the bone to germ

Question 23

what is the incidence of osteomyelitis?

Answer 23

Declining

2-13/100,000 (up to 200/100,000 in developing countries)

3/100,000 (Blyth et al, Glasgow 1997)

Mean age 6 years (10yrs pelvic)

Risk factors (1/3):

• Blunt trauma
• Recent infection

Question 24

what is the pathogenesis of acute haematogenous osteomylitis?

Answer 24

• Rare in adults
• 3 factors

Vascular anatomy - Vascular loops, Terminal branches

Cellular anatomy - Inhibited phagocytosis (low pO2)

Trauma - A factor in 30%?

More common in children due to vascular anatomy and loops of vessels around the growth plate

Some areas more infection than others

Question 25

what symptoms are seen in osteomyelitis?

Answer 25

Poorly localised pain More incidental history Some will have osteomyelitis rather than septic arthritis

Question 26

what is the microbiology of osteomyelitis?

Answer 26

this is changing

Question 27

what are Indications for surgery in osteomyelitis?

Answer 27

* Aspiration for culture * Drainage of subperiosteal abscess * Drainage of joint sepsis * Debridement of dead tissue * Failure to improve * Biopsy in equivocal cases (in case of tumour)

Question 28

what is transient synovitis?

Answer 28

Transient synovitis is an inflammation in the hip joint that causes pain, limp and sometimes refusal to bear weight. This occurs in pre-pubescent children and is the most common cause of hip pain. It occurs when a viral infection, such as an upper respiratory infection, moves to and settles in the hip joint

Question 29

When is it transient synovitis? Diagnosis of exclusion

Answer 29

* Limping, often touch weight bearing * Slightly unwell * History of viral infection eg URTI/ ear * Apyrexial * Allowing joint to be examined * Low CRP, normal WCC * May have joint infusion * Not that unwell

Question 30

what are the different kids of JIA?

Answer 30

Present with limping, swollen and stiff joints in morning that gets better

Question 31

who does JIA occur in?

Answer 31

Question 32

Some difficult cases: * History * Examination * Bloods * Imaging * Diagnosis

Question 33

AG 8 year old : * Kicked by a friend * Temp 39.80C recorded earlier in week at home * NWB, night pain * O/E pain on rotation of hip * WCC 10 (upper limit of normal), CRP 107 (very high), ESR 88 (very high), Hb 122 * Apyrexial on admission

Answer 33

* Normal pelvic radiograph * U/S fluid in both hips ? normal * Differential Diagnosis? –Septic arthritis –Transient synovitis –Osteomyelitis Normally takes day to arrange Abscess of the short external rotator muscles Treated with antibiotics

Question 34

25/03/18- 12 years old 2 week history of vague heel pain Red swollen over posterior heel Fit and well, toe weight bearing, Hb 127 CRP 34 WCC 6.4

Answer 34

Re-presented with ongoing heel pain 08/04/18 * Mild pyrexia * Touch weight bearing, sore heel, ankle joint no effusion on examination * CRP 44 (increased) * WCC 11.5 (increased) * Hb 127 * Blood cultures done Low grade osteomyelitis - on MRI

Question 35

AN July 2016 * 14 months old * Increasingly unwell at home pyexial, off milk * Mum noticed leg swelling * Admitted to medical ward with sepsis * USS left knee done reported as no effusion * Group A Strep grown in blood culture * MRI scan of leg done, verbal & written report of no collection, scant effusion in knee, extensive muscle involvement

Answer 35

High signal in muscle typical of infected myositis

Question 36

ER 12 years old, Nov 2014 * 2 week sudden onset L buttock pain * GP dx ischial bursitis & gave injection with some improvement (unusual in 12 year old) * Presented to RACH with pyrexia & unwell reduced hip movement but not terrible * Hb 104, WCC 12 (upper limit of normal), CRP 83 (raised), ESR 95 (raised)

Answer 36

Large fluid collection in iliacus muscle suggestive of an underlying abscess in the muscle and signal in bone is normal so not an osteomyelitis originally Abscess drained under CT scan No formal open surgery

Question 37

HD February 2015 * 2 ½ year old boy, left leg pain & limp, painful but willing to be examined, normal temperature * Funny looking xray; –film ‘sent’ all around the country * CRP 4, WCC 9.5, Hb 98 (slightly low) * Differential diagnosis? –? Normal variant –?osteomyelitis

Answer 37

Low Hb: Clever doctors to the rescue again •Blood film: –low retics & low monocytes –Maybe reactive but suspicious of infiltrate * Abdo USS: heterogenous mass arising from left kidney * Bone marrow biopsy/ aspirate * Dx: Metastatic neuroblastoma, diagnosed from metastasis

Question 38

JS April 2015 * Asked to see in passing by a physiotherapist * 15 year old boy, groin strain playing football 6 months ago * Increasing pain now radiating down thigh * Walks with a limp, stopped football * Woken at night

Answer 38

Osteosarcoma and was resected and artificial femur inserted

Question 39

DC January 2016 * 13 years old * Got a new skate board for his birthday last year, fell in May 2015 sustaining significant abrasions to his loin * Ongoing subsequent RIF & loin pain * Family history of ankylosing spondylitis * GP referral to physio in November & paeds in January 2016 as family concerned

Answer 39

GP referral letter: “I am concerned this 13yr old might have ankylosing spondylitis 9 months of back pain since falling off skateboard Now pain severe & persistent, affecting his sleep Sweaty at night & fatigue since glandular fever last year Paracetamol & ibuprofen are not helping Stiff and tender lumbar spine CRP 123, ESR 42, WCC 11, Hb” •WHAT IS THE DIAGNOSIS?

Question 40

what are Features that raise concern of neoplasm (Cancer)?

Answer 40

* Night pain * Often incidental trauma * Stops doing sport/ going out * Sweats and fatigue * Abnormal blood results- low Hb, atypical blood film, atypical platelets * Get a paediatrician/oncology opinion