Flashcards in MSK ||| Deck (156):
How are variations of normal posture usually noticed (2)?
1. By parents
2. On routine developmental surveillance
When does a variation in normal posture need to have intervention?
Variations are common and usually resolve without treatment but:
If severe, progressive, painful, functionally limiting or asymmetrical, they should be referred for a specialist opinion
What is pes planus?
At what age are flat feet common in? Why (2)?
Very common in toddlers learning to walk:
1. .Due to flatness of the medial longitudinal arch
2. Presence of a fat pad which disappears as the child gets older
In a toddler with flat feet, what manouvers can be done to demonstrate the arch (2)?
1. Standing on tiptoe
2. Passively extending the big toe
How can a fixed flat foot present in older children (2)?
1. Often painful
2. Presents with absence of arch when tip toeing
What can a fixed flat foot in a child indicate (3)?
1. Associated tendo-Achilles contracture (ankle - tendinitis of the Achilles tendon, generally caused by overuse)
2. Tarsal coalition - Abnormal connecting bridge of tissue between two normally-separate tarsal bones
3. Juvenile inflammatory arthropathy (JIA) - an autoimmune, noninfective, inflammatory joint disease of more than 6 weeks duration in children less than 16 years of age
What are the management options for a child with a fixed flat foot (2)?
1. Referral to paediatric rheumatology or paediatric orthopaedic surgeon
2. Symptomatic flat feet can be helped by footwear advice and perhaps an arch support
What is developmental dysplasia of the hip (DDH)?
A spectrum of disorders ranging from dysplasia to subluxation, to frank dislocation of the hip
What is hip dysplasia?
An abnormality of the hip joint where the socket portion does not fully cover the ball portion, resulting in an increased risk for joint dislocation
What is hip subluxation?
A partial dislocation where the ball has started to come out of the socket but has not come fully out or dislocated
What are the screening protocols for DDH?
Neonatal screening of newborn:
1. Barlow manoeuvre - checking if hip can be dislocated posteriorly out the acetabulum
2. Ortolani manoeuvre - If hip can be rlocated back into the acetabulum on abduction
Examination repeated at 8 weeks
If DDH is not picked up at routine examination, how may it present after (4)?
1. Limp or abnormal gait
2. Asymmetry of skinfolds around the hip
3. Limited abduction of the hip
4. Shortening of affected leg
What is the incidence of hip abnormalities detected on neonatal screening?
6-10 per 1000 live births detected
What is the true birth prevelance of DDH?
1.3 per 1000 live births
Why are some cases of DDH missed at screening (2)?
1. Inexperience of the examiner
2. Undetectable dislocation at that stage e.g. only a mildly shallow acetabulum
How is a DDH managed on detection (4)?
1. Referral to a specialist orthopaedic for an opinion
2. An ultrasound scan following an abnormal clinical examination for a detailed assessment of the hip - quantifying degree of dysplasia and whether there is subluxation or dislocation.
3. If indicated - infant can be placed in a splint or harness to keep the hip flexed and abducted for several months. Progress monitored by x-ray/USS. This usually obtains a satisfactory response
4. If conservative measures don't work, surgery can be done
What is the outlook of DDH (3)?
1. Most resolve spontaneously
2. In those who require intervention, a satisfactory response is obtained through a splint/harness
3. If these don't work, surgery can be performed
What are some risk factors for DDH (5)?
1. Higher risk in some Native American groups
2. Swaddling infants
3. Breech birth
What are the 2 broad groups of scoliosis?
1. Non-structural - Reversible and function, due to e.g. muscle spasm/pain/difference in leg length
2. Structural - irreversible, due to a rotation of the vertebral bodies which causes a prominence in the back from rib asymmetry
What is scoliosis?
A lateral curvature in the frontal plane of the spine
What are the causes of structural scoliosis (3)?
1. Idiopathic - most common
2. Congenital - congenital structural defect of the spine e.g. spina bifida syndromes
3. Secondary - related to other disorders such as neuromuscular imbalance e.g. CP, muscular dystrophy
At what age does idiopathic scoliosis usually occur?
1. Early onset
2. Late onset
Early onset - <5 years old
Late onset - mainly girls 10-14 years of age during their growth spurt
What should be done in the examination of scoliosis (4)?
1. Inspection of child's back while standing up straight
2. In mild scoliosis, there may be irregular skin creases and difference in shoulder height
3. Inspecting the back while the child is bent forward - scoliosis can be identified like this
4. If scoliosis disappears on forward bending, it is postural although leg lengths should be checked.
What is the outlook of scoliosis (4)?
1. Mild scoliosis will resolve spontaneously or progresses minimally
2. If more severe, the severity and progression of the curvature of the spine is determined by X-ray
3. Severe cases are managed in specialist spinal centres where bracing can be considered
4. Surgery can be performed if very severe or if there is coexisting pathology
What is a serious complication of severe scoliosis?
Cardiorespiratory failure from distortion of the chest
What is torticollis?
Wry neck - a dystonic condition defined by an abnormal, asymmetrical head or neck position
What is the most common cause of torticollis in infants (1)? How does it present (4)?
Sternomastoid tumour (congenital muscular torticollis)
1. Occur in first few weeks of life
2. Present with a mobile, non-tender nodule, which can be felt within the body of the sternocleidomastoid muscle
3. There may be restriction of head turning and tilting of the head
4. Usually resolves in 2-6 months
What are possible causes of torticollis later in childhood (5)?
1. Muscular spasm
2. Secondary to ear, nose or throat infection
3. Spinal tumour (such as osteiod osteoma)
4. Cervical spine arthritis
5. Posterior fossa tumour
What is the cause for acute torticollis?
Neck muscle spasm
What is the management of acute torticollis (3)?
1. Reassurance - usually resolves within 24-48 hours
3. Gentle exercise
What are the 2 types of limp?
Acute painful limp
Chronic or intermittent limp
What is transient synovitis (irritable hip)?
The most common cause of acute hip pain in children that usually follows or is accompanied by a viral infection
What age does transient synovitis usually occur in?
2-12 years old
What is the clinical presentation of transient synovitis (4)?
1. Sudden onset of pain in the hip or a limp
2. There is no pain at rest but a decreased range of movement, particular internal rotation
3. Pain may be referred to the knee
4. The child is afebrile or has a mild fever and does not appear ill
What is the main ddx of transient synovitis? What investigations should be done to differentiate between them?
Early septic arthritis of the hip joint - joint aspiration and blood cultures are mandatory
How is transient synovitis managed (2)?
1. Bed rest
2. Rarely, skin traction
It usually improves within a few days
What is Perthes disease?
An avascular necrosis of the capital femoral epiphysis of the femoral head due to interruption of the blood supply, followed by revascularisation and reossification over 18-36 months
What groups of children does Perthes disease usually affect?
What is the presentation of Perthes disease (3)?
1. Insidious onset
2. Onset of a limp or hip/knee pain
3. Bilateral in 10-20%
What is Perthes disease often mistaken for?
If Perthes disease is suspected, what investigation should be done?
What would it show?
X-ray of both hips (including frog views)
Early signs of Perthes = increased density in femoral head
Later signs of Perthes = femoral head becomes fragmented and iregular
What are the 3 scans that a child with suspected Perthes disease should receive to help with the diagnosis (3)?
1. X-ray, this can be repeated if initial x-ray is normal and symptoms persist
2. Bone scan
3. MRI scan
What are the treatments for Perthes disease (3)?
2. Physiotherapy to optimize hip movement
3. In some cases: traction, plaster casts and surgery
What is the prognosis of Perthes disease?
What are the possible long-term complications?
Prognosis is usually good, especially:
-below 6 years of age
-less than half of the epiphysis involved
For older children/more extensive involvement of the epiphysis/deformity of the femoral head and metaphyseal damage:
-more likely to have subsequent degenerative arthritis in adult life
What is a slipped capital femoral epiphysis (SCFE) (2)?
1. Results in displacement of the epiphysis of the femoral head posterio-inferiorly
2. Requires prompt treatment in order to prevent avascular necrosis
What groups of children are at a higher risk of a SCFE (3)?
1. 10-15 years of age during adolescent growth spurt
2. Obese boys
3. Associated with metabolic endocrine abnormalities e.g. hypothyroidism and hypogonadism
What is the presentation of SCFE (3)?
1. Limp or hip pain which may be referred to the knee
2. Onset may be acute, following minor trauma, or insidious
3. Bilateral in 20%
How is the diagnosis of SCFE confirmed?
On X-ray, request a frog lateral view
Fracture through the growth plate (physis), which results in slippage of the overlying end of the femur (epiphysis)
What does examination of a patient with SCFE show (2)?
1. Restricted abduction
2. Internal rotation of the hip
What is the management of SCFE?
Surgical - pin fixation in situ
What is the definition of juvenile idiopathic arthritis (JIA) (3)?
1. Persistent joint swelling of >6 weeks duration
2. Presents before 16 years of age
3. Absence of infection or any other defined cause
How common is JIA in the UK?
The most common chronic inflammatory joint disease in children and adolescents in the UK
What are the 7 subtypes of JIA? How common are each of them?
1. Oligoarthritis (persistent) (49%)
2. Oligoarthritis (extended) (8%)
3. Polyarthritis (RF negative) (16%)
4. Polyarthritis (RF positive) (3%)
5. Systemic arthritis (9%)
6. Psoriatic arthritis (7%)
7. Enthesitis-related arthritis (7%)
8. Undifferentiated arthritis (1%)
What is the onset age for each of the subtypes of JIA?
1. Oligoarthritis (persistent) = 1-6 years
2. Oligoarthritis (extended) = 1-6 years
3. Polyarthritis (RF negative) = 1-6 years
4. Polyarthritis (RF positive) = 10-16 years
5. Systemic arthritis = 1-10 years
6. Psoriatic arthritis = 1-16 years
7. Enthesitis-related arthritis = 6-16 years
8. Undifferentiated arthritis = 1-16 years
What are the sex ratios for each of the subtypes of JIA (F:M)?
1. Oligoarthritis (persistent) = 5:1
2. Oligoarthritis (extended) = 5:1
3. Polyarthritis (RF negative) = 5:1
4. Polyarthritis (RF positive) = 5:1
5. Systemic arthritis = 1:1
6. Psoriatic arthritis = 1:1
7. Enthesitis-related arthritis = 1:4
8. Undifferentiated arthritis = 2:1 (variable)
Which subtypes of JIA are more likely to affect females?
1. Oligoarthritis (persistent)
2. Oligoarthritis (extended)
3. Polyarthritis (RF negative)
4. Polyarthritis (RF positive)
5. Undifferentiated arthritis
Which subtypes of JIA affect males and females equally?
1. Systemic arthritis
2. Psoriatic arthritis
What is the articular pattern of the JIA subtype: Oligoarthritis (persistent)?
1-4 (max) joints involved. Knee, ankle or wrist most common
What is the articular pattern of the JIA subtype: Oligoarthritis (Extended)?
>4 joints involved after first 6 months. Asymmetrical distribution of large and small joints
What is the articular pattern of the JIA subtype: Polyarthritis (RF negative)?
Symmetrical large and small joint arthritis, often with marked finger involvement.Cervical spine and temporomandibular joint may be involved
What is the articular pattern of the JIA subtype: Polyarthritis (RF positive)?
Symmetrical large and small joint arthritis, often with marked finger involvement
What is the articular pattern of the JIA subtype: Systemic arthritis?
Oligoarthritis or polyarthritis. May have aches and pains in joints and muscles (arthralgia/myalgia) but initially no arthritis
What is the articular pattern of the JIA subtype: Psoriatic arthritis?
Usually asymmetrical distribution of large and small joints, dactylitis
What is the articular pattern of the JIA subtype: Enthesitis-related arthritis?
Lower limb, large joint arthritis initially, mild lumbar spine or sacroiliac involvement later on
What is the articular pattern of the JIA subtype: Undifferentiated arthritis?
Overlapping articular and extra-articular patterns between 2 or more subtypes or insufficient criteria for subclassification
What are the extra-articular features of the JIA subtype: Oligoarthritis (persistent) (2)?
What is the prognosis?
1. Chronic anterior uveitis in 20%
2. Leg length discrepancy
What are the extra-articular features of the JIA subtype: Oligoarthritis (extended) (2)?
What is the prognosis?
1. Chronic anterior uveitis in 20%
2. Asymmetrical growth
What are the extra-articular features of the JIA subtype: Polyarthritis (RF negative) (3)?
What is the prognosis?
1. Low-grade fever
2. Chronic anterior uveitis 5%
3. Late reduction of growth rate
What are the extra-articular features of the JIA subtype: Polyarthritis (RF positive) (2)?
What is the prognosis?
1. Rheumatoid nodules 10%
2. Similar to adult rheumatoid arthritis
What are the extra-articular features of the JIA subtype: Systemic arthritis?
What is the prognosis?
Acute illness, malaise, high daily fever initially, with salmon-pink, macular rash, lymphadenopathy, hepatosplenomegaly, serositis
Prognosis variable to poor
What are the extra-articular features of the JIA subtype: Psoriatic arthritis?
What is the prognosis?
Psoriasis, nail pitting or dystrophy, chronic anterior uveitis 20%
What are the extra-articular features of the JIA subtype: Enthesitis-related arthritis (2)?
What is the prognosis?
1. Enthesitis - local inflammation at insertion of tendons or ligaments into bone, often in feet, Achilles insertion
2. Occasional acute uveitis
What are the extra-articular features of the JIA subtype: Undifferentiated arthritis?
What is the prognosis?
What are the lab abnormalities of the JIA subtype: Oligoarthritis (persistent)?
What are the lab abnormalities of the JIA subtype: Oligoarthritis (extended)?
What are the lab abnormalities of the JIA subtype: Polyarthritis (RF positive)?
RF+ long term
What are the lab abnormalities of the JIA subtype: Systemic arthritis (3)?
2. Raised neutrophils and platelets
3. High acute-phase reactants
What are the lab abnormalities of the JIA subtype: Enthesitis-related arthritis?
What are features in the history of JIA (5)?
1. Gelling (stiffness after periods of rest, such as long car rides)
2. Morning joint stiffness
4. In a young child
-deterioration in behaviour or mood
-Avoidance of previously enjoyed activities
5. Presentation can be indolent
How does the joint swelling usually present in JIA (2)?
1. Initially there may be only minimal evidence of joint swelling
2. Subsequently there may be swelling of the joint due to fluid within it, inflammation, chronic arthritis, proliferation of the synovium and swelling of the periarticular soft tissues
What are the investigations done for JIA and what would they show (2)?
1. As presentation can be indolent, baseline investigations are often initially normal:
-FBC, inflammatory markers, negative rheumatoid factor and radiographs
2. Antinuclear factor may be present
What must you check for when presented with a child with widespread joint pain, fatigue or multisystem involvement?
A connective tissue disorder
What can occur in the long term with uncontrolled disease activity of JIA?
1. Bone expansion from overgrowth
-In the knee can cause leg lengthening or valgus deformity
-In the hands, discrepancy in digit length
-In the wrist, advancement of bone age
If systemic features are present in a child, what must be considered?
Sepsis and malignancy
What are the complications of JIA (6)?
1. Chronic anterior uveitis
2. Flexion contractures of the joints
3. Growth failure
4. Constitutional problems
What is the epidemiology of chronic anterior uveitis?
What are the clinical features and the consequences of chronic anterior uveitis (2)?
What monitoring is needed?
1. Usually asymptomatic in the early stages
2. If untreated, can lead to severe visual impairment due to cataract and glaucoma
Needs regular opthalmological screening with a slit lamp, especially for children with oligoarticular disease and those who are antinuclear antibody positive.
What is chronic anterior uveitis?
Inflammation of the uvea, the pigmented layer that lies between the inner retina and the outer fibrous layer composed of the sclera and cornea
How do flexion contractures of the joints occur?
What are the consequences of chronic untreated disease?
When the joint is held in the most comfortable position, thereby minimising intra-articular pressure.
Joint destruction and need for joint replacement - it is avoidable with early treatment
What aspects of JIA can contribute to growth failure (2)?
How avoidable is growth failure?
1. Generalised from anorexia, chronic disease and systemic corticosteroid therapy
2. Localised overgrowth such as leg length discrepancy due to prolonged active knee synovitis and undergrowth, such as micrognathia, usually seen in long-standing or suboptimally treated arthritis due to premature fusion of epiphyses.
Avoidable with early diagnosis and treatment
What are some constitutional problems that can occur with JIA (2)?
1. Anaemia of chronic disease
2. Delayed puberty
What are some of the contributing factors to osteoporosis in JIA (4)?
2. reduced weight bearing
3. systemic corticosteroids
4. delayed menarche
How do you reduce the risk of osteoporosis with JIA (3)?
1. Dietary supplements of calcium and vitamin D
2. Regular weight-bearing exercise
3. Minimise oral corticosteroid use
How common is amyloidosis?
What are the consequences of it?
Causes proteinuria and subsequent renal failure and has high mortality
What is the overall aim of management of JIA?
To induce remission asap
What is the medical management of JIA? Why are they used (5)?
1. NSAIDs and analgesia - relieves symptoms during flares
2. Joint injections under US guidance
-first line treatment for oligoarticular JIA
-In polyarticular disease multiple joint injections are used as bridging agents when starting methotrexate
3. Methotrexate - early use reduces joint damage
-Effective in 70% with polyarthritis
-Regular blood monitoring is required for abnormal liver function and BM suppression
4. Systemic corticosteroids - avoided if possible to to minimise risk of growth suppresson and osteoporosis
-May be life-saving for severe systemic arthritis or macrophage activation syndrome
5. Cytokine modulators
-anti-TNF alpha, IL-1, IL-6, CTLA-4 available
-Useful in severe disease refractory to methotrexate
Who are the members of the MDT in the management of JIA (8)? What role do they play?
1. Specialist paediatric rheumatology MDT team
-Experts in the use of immunosuppressive treaments and intra-articular corticosteroid injections
2. Education and support for child and family
3. Physical therapy to maintain joint function
7. Schools, social services and primary healthcare providers - child encouraged to take part in all activities except contact sports during active flares.
8. Transitional care programmes to help facilitate changes through adolescence and young adulthood.
What is the outlook for JIA (3)?
1. Good disease control can be expected with good QOL
2. Long-term outcome studies show that 1 in 3 children will need ongoing treatment into adult years to maintain remission
3. There is significant psychosocial morbidity with impact on schooling and employment outcomes
How common is reactive arthritis?
Most common form of arthritis in childhood
What are the clinical features of reactive arthritis (3)?
1. Transient joint swelling (usually <6 weeks) often of ankles or knees
2. Usually follows (or rarely accompanies) evidence of extra-articular infection
3. Low grade fever
What are the main causative organisms of reactive arthritis?
1. In children (4)
2. In adolescents (4)
Adolescents - often a STD
4. Borrelia burgdorferi (Lyme disease)
What investigations can be done for reactive arthritis (5)? What would they show?
1. Acute-phase reactants are normal or mildly elevated
2. X-rays are normal
3. The urethra, cervix and the throat may be swabbed in an attempt to culture the causative organisms.
4. Cultures may also be carried out on urine and stool samples or on fluid obtained by arthrocentesis.
5. A blood test for the genetic marker HLA-B27 may also be performed. About 75 percent of all the patients with Reactive arthritis have this gene
What are the treatments for reactive arthritis (2)?
What is the outcome?
1. No treatment needed
2. NSAIDs can be given
Full recovery can be expected by 6 months
What is osteomyelitis?
Infection of the metaphysis of long bones
What are the most common sites of osteomyelitis (2)?
1. Distal femur
2. Proximal tibia
How does osteomyelitis occur (2)?
1. Usually due to haematogenous spread of the pathogen
2. Can be by direct spread from an infected wound
What are the common causative pathogens of osteomyelitis (3)?
1. Staph. aureus - most common
3. Haemophilus influenzae if not immunized
What possible causative organisms should be considered in sickle cell patients (2)?
What possible causative organisms should be considered in immunodeficient patients?
What is a complication of osteomyelitis in areas where the joint capsule is inserted distal to the epiphyseal plate e.g. hip?
What is the presentation of osteomyelitis?
1. Child (4)
2. Infant (3)
1. Markedly painful, immobile limb (pseudoparesis) in a child with an acute febrile illness
2. Directly over the infected site there is swelling and exquisite tenderness, and may be erythematous and warm
3. Movement of limb causes severe pain
4. May be a sterile effusion of an adjacent joint
1. Presentation is more insidious
2. Swelling or reduced limb movement is the initial sign
3. Beyond infancy, it may present with back pain in a vertebral infection or with a limp or groin pain in infection of the pelvis
What is the investigation of osteomyelitis (6)? What do they show?
1. Blood cultures - usually positive
2. WBC and acute-phase reactants high
-Initially normal other than soft tissue swelling
-Takes 7-10 days for subperiosteal new bone formation and localised bone rarefaction to become visible
4. USS may show periosteal elevation at presentation
5. MRI allows identification of infection in the bone and differentiation of bone from soft tissue infection
6. Radionuclide bone scan can help if site of infection is unclear
What is the treatment of osteomyelitis (5)?
1. Prompt treatment with iv abx required for several weeks to prevent bone necrosis, chronic infection with a discharging sinus, limb deformity and amyloidosis. Given until there is clinical recovery and acute-phase reactants have returned to normal
2. Iv is followed by oral therapy for several weeks
3. Aspiration or surgical decompression of the subperiosteal space may be performed if the presentation is atypical or in an immunodeficient child
4. Surgical drainage if condition does not respond rapidly to abx therapy
5. Affected limb is initially rested in a splint and subsequently mobilized.
What are the risks of undertreated/untreated osteomyelitis (8)?
1. Chronic osteomyelitis
3. Septic arthritis
4. Pyogenic abscess (Brodie abscess)
6. Bone necrosis
7. Limb deformity
What is chronic osteomyelitis?
A severe, persistent, and sometimes incapacitating infection of bone
What is subacute osteomyelitis?
What are its clinical features?
A distinct form of osteomyelitis where the characteristic signs and symptoms of the acute form of the disease are absent.
Brodie abscess is one type of subacute osteomyelitis - low-grade pyogenic abscesses of the bone
Characterized by mild to moderate pain, usually described as a persistent ache; intermittent symptoms; insidious onset; and, often, a long delay between the onset of pain (the most common presenting symptom) and the diagnosis
What is septic arthritis?
A serious infection of the joint space, as it can lead to bone destruction
In what age is septic arthritis most common in?
Most common in children less than 2 years old
How does septic arthritis occur (3)?
1. Usually results from haematogenous spread
2. Can occur following a puncture wound or infected skin lesions e.g. chickenpox
3. In young children, can result from spread from adjacent osteomyelitis into joints where the capsule inserts below the epiphyseal growth plate
How many joints are usually affected in septic arthritis?
Usually 1 joint
What is the most common causative organism of septic arthritis in children beyond the neonatal age?
What is another important causative organism of septic arthritis in children apart from Staph. aureus?
Hib in those not immunised. Often affects multiple sites
What should you look for in a patient with septic arthritis?
Underlying illnesses such as immunodeficiency and sickle cell disease
What is the presentation of septic arthritis (4)?
1. Erythematous, warm, acutely tender joint, with reduced range of movement in an acutely unwell, febrile child
2. Infants often hold the limb still (pseudoparesis) and cry if it is moved
3. There may be a joint effusion detectable accompanied by marked tenderness over the bone
4. In toddlers, it may present as a limp or pain referred to the knee - difficult to diagnose septic arthritis in toddlers as joint is covered by subcut fat.
What investigations are done for septic arthritis and what would they show (6)?
1. WBC and acute phase reactants increased
2. Blood cultures must be done
3. US of deep joints such as hip - can identify effusion
4. X-rays used to exclude trauma and other bony lesions, although joint itself looks normal apart from widening of the joint space and soft tissue swelling
5. MRI/radioisotope bone scan may be indicated if site of infection is unclear
6. Aspiration of the joint space under US guidance for organisms and culture is the definitive investigation
What is the definitive investigation for septic arthritis?
How promptly should it be done?
Aspiration of the joint space under US guidance for organisms and culture
Should be done immediately unless it significantly delays giving Abx
What treatments are given for septic arthritis (3)?
1. Prolonged course of Abx, initially iv
2. Washing out of the joint or surgical drainage may be needed if resolution does not occur rapidly or if the joint is deep-seated, such as the hip
3. Joint is initially immobilised in a functional position, but must subsequently mobilised to prevent permanent deformity
Why is early treatment of septic arthritis important?
To prevent destruction of the articular cartilage and bone
Why is diagnosis of septic arthritis of the hip difficult in toddlers?
It is covered by subcut fat
What is rickets?
What is osteomalacia?
Rickets = Failure in mineralisation of the growing bone or osteoid tissue
Osteomalacia = Failure of mineralisation of mature bone
What are the causes of rickets (4)?
1. Nutritional (primary)
-Decreased exposure to sunlight
-Maternal Vit D deficiency
-Diets low in Ca, phosphorus and Vit D
-Strict vegan diets
-Prolonged paraenteral nutrition in infancy
2. Intestinal malabsorption
-Small bowel enteropathy e.g. coeliac disease
-Pancreatic insufficiency e.g. CF
-Cholestatic liver disease
-High phytic acids in diet e.g. chapattis
3. Defective production of 25-hydroxyvitamin D
-Chronic kidney disease
-Fanconi syndrome (renal loss of phosphate)
-Inherited disorders (rare)
4. Increased metabolism of 25-hydroxyvitamin D
-Enzyme induction by anticonvulsants e.g. phenobarbital
What is the major cause of rickets in low and middle income countries?
What is the major cause of rickets in high income countries (2)?
1. Nutritional rickets in black or Asia infants who are totally breastfed til late infancy (as formula milk is supplemented with Vitamin D)
2. Extremely preterm infants from dietary deficiency of phosphorus, with low stores of calcium and phosphorus
What are the clinical features of rickets (12)?
1. Earliest sign - sensation of pressing a ping-pong ball firmly over the occipital or posterior parietal bones (craniotabes)
3. Poor growth/short stature
4. Frontal bossing of skull
5. Delayed closure of anterior fontanelle
6. Delayed dentition
7. Harrison's sulcus
8. Expansion of metaphyses, especially wrists
9. Bowing of weight-wearing bones
12. Cardiomyopathy/heart failure
How is rickets diagnosed (3)?
1. Dietary history e.g. prolonged breastfeeding
2. Blood tests
-Serum Ca low or normal
-plasma alkaline phosphatase activity high
-25-hydroxyvitamin D may be low
-Parathyroid hormone elevated
3. X-ray of wrist joint
-shows cupping and fraying of the metaphyses and a widened epiphyseal plate
What is the management of nutritional rickets (4)?
What is the course of disease?
Nutritional rickets managed by:
1. dietary advice, foods high in vit D are oily fish and egg yolk
2. correction of predisposing risk factors
3. daily administration of Vitamin D3
4. If compliance an issue, a single oral high dose of Vit D3 can be given, followed by the daily maintenance dose
Healing occurs in 2-4 weeks but complete reversal of boney deformities can take years
What can be used to monitor the healing of rickets (3)?
1. Lowering of alkaline phosphatase
2. Increasing Vit D levels
Why is Vitamin D important for the bones (4)?
Maintains skeletal calcium balance by:
1. Promoting calcium absorption in the intestines
2. Promoting bone resorption by increasing osteoclast number
3. Maintaining calcium and phosphate levels for bone formation
4. Allowing proper functioning of parathyroid hormone to maintain serum calcium levels.
How common is systemic lupus erythematosus (SLE) in children?
What group does it usually affect?
Usually affects adolescent females
How does SLE usually present in children (3)?
3. Malar rash (often photosensitive)
What are complications of SLE?
Organ involvement of kidneys, lung or CNS
What is osteogenesis imperfecta (brittle bone disease)?
A group of disorders of collagen metabolism causing bone fragility, with bowing and frequent fractures
How many types of osteogenesis imperfecta are there?
Which is most common?
At least 9 types
Type 1 is most common
What inheritance is type 1 osteogenesis imperfecta?
What are its clinical features (3)?
1. Fractures during childhood
2. Blue appearance to sclera
3. Some develop hearing loss
What is the inheritence of type 2 osteogenesis imperfecta?
What are its clinical features (2)?
Inheritence variable but mostly autosomal dominant
1. Severe, lethal with multiple fractures already present before birth
2. Many affected infants are stillborn
What is skeletal dysplasia?
A general term for disproportionately short stature
What is the pathophysiology of skeletal dysplasia?
Until skeletal maturity, cartilage persists at the ends of bone in the growth plate, which is responsible for longitudinal bone growth. The cartilaginous template is eventually replaced by bone. Many of the genes mutated in skeletal dysplasias encode proteins that play critical roles in the growth plate
What are some different types of skeletal dysplasia (4)? Which is most common?
1. Achondroplasia - most common
2. Fibrous dysplasia
4. Osteogenesis imperfecta
What inheritence is achondroplasia?
What are the clinical features (4)?
Autosomal dominant but 50% are new mutations
1. Short stature from marked shortening of limbs
2. Large head
3. Frontal bossing
4. Depression of the nasal bridge
What are the principles of physical and surgical management of skeletal dysplasia?
Surgical - prevent spinal cord compression and bone-lengthening surgery can be done
Physical - Pain and disability may be ameliorated by physical therapy
What are the different categories of fractures (2)?
1. Complete or incomplete
2. Compound (open) or simple (closed) i.e. overlying skin is intact
What are the different patterns of fractures (8)?
1. Linear fracture: A fracture that is parallel to the bone's long axis
2. Transverse fracture: A fracture that is at a right angle to the bone's long axis
3. Oblique fracture: A fracture that is diagonal to a bone's long axis (more than 30°)
4. Spiral fracture: A fracture where at least one part of the bone has been twisted
5. Compression fracture/Wedge fracture: usually occurs in the vertebrae, for example when the front portion of a vertebra in the spine collapses due to osteoporosis
6. Impacted fracture: A fracture caused when bone fragments are driven into each other
7. Avulsion fracture: A fracture where a fragment of bone is separated from the main mass
8. Greenstick: Bone is bent on one side and partially broken on the other
What is the difference between the bones of adults and children?
The bones of a child are more likely to bend than to break completely because they are softer and the periosteum is stronger and thicker. The ligaments are also proportionately stronger.
What fractures are children more likely to get (2)?
The fractures that are most common in children are the incomplete fractures:
1. Greenstick - bend on one side of the bone and a partial fracture on the other side
2. Torus or Buckle fractures - caused by impaction. They are usually the result of a force acting on the longitudinal axis of the bone: they are typically a consequence of a fall on an outstretched arm, so they mainly involve the distal radial metaphysis