Paediatric Musculoskeletal Disorders Flashcards
Acute Arthritis
presents with the cardinal signs of inflammation; In Monoarthritis, typically systemically unwell with fever (Septic Arthritis, Osteomyelitis; Urgent management required)
Most common arthritis
Reactive Arthritis is the most common arthritis; Transient joint swelling often in Ankles/Knees;
o Low grade fever; Normal or mildly-elevated CRP, Normal XR
o NSAIDs, complete recovery anticipated
Causes of reactive arthritis
Often caused by Enteric bacteria (Salmonella, Shigella, Campylobacter, Yersinia); Viral Infections, STIs in adolescents (Chlamydia, Gonorrhoea), Mycoplasma and Lyme disease are other causes
Other causes of polyarthritis
Other causes of polyarthritis include Inflammatory Bowel Disease-related, Vasculitis-related (e.g. HSP, Kawasaki), Haematological and Malignant disease, Connective Tissue Disease
Septic Arthritis
Serious infection of joint space leading to Bone Destruction; Most commonly <2yrs; Mostly Haematogenous spread but can also be due to break in skin or infected lesions
• Typically, Mono or Oligoarthritis; Most common, beyond Neonatal period is S aureus; HiB used to be of concern but less so with immunisation
o Need to consider immunodeficiency or predisposing illness, such as Sickle Cell
Presentation of Septic Arthritis
Presents with Erythematous, Warm, acutely tender joint with reduced ROM in acutely unwell and febrile child; Infants often hold limb still (Pseudoparesis) and cry if moved
o Joint effusion; Bone tenderness if Osteomyelitis (up to 15% cases of Osteomyelitis have Septic Arthritis as well
Septic Hip
Septic Hip might be hard to identify due to subcutaneous fat protecting joint; Signs include Pseudoparesis, Limping gait or Knee referred pain
Septic Arthritis: Investigations
FBC, CRP, Blood Cultures
• US of deep joints to identify Effusion, XR to exclude trauma and other bone lesions
o XR normal in Septic Arthritis, other than Joint Space widening and Soft Tissue swelling
• US-Guided Aspiration with MC+S, Ideally, before antibiotics started;
Management of Septic Arthritis
Prolonged course IV Abx
o Initially joint immobilised while IV Abx; mobilisation after improvement
• Wash out or surgical drainage might be required if resolution does not occur rapidly, or for deep-seated infections
Juvenile Idiopathic Arthritis
Most common Chronic Inflammatory Joint disease; Persistent swelling >6/52 before 16yrs, in absence of infection of other cause; 1 in 1000
o 95% have disease clinically and immunogenetically different from RA
Juvenile Idiopathic Arthritis: Classification
Clinically classified, according to Number of joints affected, Systemic symptoms, or other Extra-articular features; Also, Rheumatoid Factor and HLA-B27 classified
Juvenile Idiopathic Arthritis: Presentation
Gelling (Stiffness after rest), Morning Joint Stiffness, Pain; May present as Intermittent Limp, Deterioration in Behaviour and Activity Avoidance
Initially only minimal evidence of joint swelling; Subsequently followed by Effusion, Inflammation, Chronic Arthritis, Synovial Proliferation and Periarticular Swelling
Complications of JIA
- Uncontrolled disease can lead to Overgrowth Bone Expansion, resulting in Limb and Hand deformities; Flexion contractures can occur in longer term
- Chronic Anterior Uveitis – Common but usually asymptomatic; If untreated, can lead to Cataract and Glaucoma; Requires regular Ophthalmic screening
- Growth Failure – Anorexia, Chronic Disease, Systemic Corticosteroid therapy; May also be due to localised overgrowth due to inflammation and undergrowth due to premature fusion
- Constitutional Problems – Anaemia of Chronic Disease and Delayed Puberty
- Osteoporosis and Amyloidosis (rarely, high mortality from renal failure
JIA Prognosis
Good disease control and QOL if management concordance; Significant morbidity from previous inflammation, joint damage, visual impairment and fractures due to Steroid use; 1/3 will need treatment in adult years to maintain remission
Management of JIA: MDT
Deformity and Disability much less common with Early Diagnosis and new treatments; Aims to induce remission as soon as possible
o All suspected should be managed by Specialist Paediatric Rheum MDT;
o Education and Support for family; PT to maintain joint function, Ophthalmology etc
Management of JIA: Medication
NSAIDs and Analgesia – Non-disease modifying, but effective symptom relief
• Joint Injections (±US-guided) – Effective, First-line for Oligoarticular JIA; Used for bridging for Polyarticular JIA before starting Immunosuppression; Often requires sedation or Entonox
• Methotrexate – Early use reduces joint damage; 70% effective in Polyarthritis, requires regular blood monitoring (LFTs, BM Suppression); Nausea common
• Systemic Corticosteroids – Avoided if possible due to Growth Suppression and Osteoporosis risk; Pulsed IV Methylprednisolone for Severe Polyarthritis
Management of JIA: What to use if refractory to methotrexate
Biologics – Useful for Severe Disease refractory to Methotrexate
Management of JIA: Refractory Disease
T-cell depletion, followed by Autologous Haemopoietic Stem Cell Rescue if Refractory disease
Rickets
Failure of Growing Bone Mineralisation; C/f Failure for Mature Bone = Osteomalacia
Risk factors for Rickets
o Higher risk in children breastfed into late infancy, as well as Preterm infants, due to Phosphate deficiency, or low Calcium and Phosphate stores
o Malabsorption disorders – CF, Coeliac, Pancreatic Insufficiency; Fanconi Syndrome (Loss of Renal Phosphate)
o Drugs – Phenytoin, Phenobarbital interfere with Vitamin D Metabolism; Can also be deranged due to Hepatic and Renal Disease, and few Genetic disorders
Signs of Rickets
Earliest sign is Craniotabes over Occiput or Parietal bones; Palpable Costochondral junctions (Rachitic Rosary), Wrists and Ankles may be widened; Harrison’s Sulcus of the Ribs
Diagnosis of Rickets
Diagnosis based on Dietary History, Low Ca, Low Phos, High Alk Phos, Low 25-OH Vit D and High PTH; XR Wrist shows Cupping and Frays of Metaphysis, and Widened Epiphyseal plate
Management of Rickets
Diet advice (Oily fish and Egg Yolk; Supplemented Milk, Cereals, Fruit Juice), Managing Predisposing factors, Daily Vitamin D3 (Cholecalciferol) ± Single high dose prior o Healing occurs in 2 – 4 weeks, monitored by low Alk Phos, Rising Vit D and XR change
