discuss the orthopaedic manifestations of sickle cell disease
TRANSCRIPT
Discuss the Orthopaedic Manifestations of SCD &
their ManagementDr. Arojuraye S.A
National Orthopaedic HospitalDala-Kano
Outline
Introduction Pathophysiology Orthopaedic manifestations Management Conclusion
Introduction
SCD = Inherited disorder due to HbS Substitution of valine for glutamic acid at 6th a.a of the
ß globin chain Inheritance = autosomal recessive Major genotypes = SS, SC & sickle-beta thalassemia HbS is poorly soluble It assumes sickle shape when deoxygenated
Introduction…
Incidence Black American
AS = 8 – 10% SS = 0.2 - 0.5%
West African AS = 20%
Introduction…
Diagnosis Peripheral blood smear = sickle rbc Hb electrophoresis = abnormal haemoglobins Diagnosis of the major genotypes = simple Differentiation of various subtypes = complex
Introduction… 1910: First description of SCD was made in Chicago
by Herrick.
1927: Hahn & Gillespie showed that sickling of the rbc was induced by deoxygenation & reversed with reoxygenation.
1949: Electrophoretic abnormalities of Hb were demonstrated by Pauling et al
Pathophysiology
Hypoxia & dehydration Sickling Membrane distortion Rbc stickiness
Haemolysis & Vaso-occlusion
Pathophysiology…
Haemolysis results from destruction of the sickled rbc by monocytes & macrophages.
Vaso-occlusion is due to
entrapment of sickled cells in the microcirculation = ischaemia.
Pathophysiology…
Clinical manifestations
CNS: CVA, meningitis
Ocular: Retinopathy
Pulmonary: Acute chest syndrome, pneumonia, restrictive lung disease
Clinical manifestations… Renal: Haematuria, nephropathy
Spleen: Massive splenomegaly, autosplenectomy
Biliary: Cholelithiasis, cholecystitis
CVS: HF, MI, cor pulmonale
Orthopaedic manifestations
Acute Vaso-occlusive crisis Osteomyelitis Septic arthritis Stress fracture Vertebral collapse
Chronic Osteonecrosis Chronic arthritis Chronic osteomyelitis Osteoporosis Impaired growth
Vaso-occlusive crisisVOC Affects virtually all patients Begins in late infancy & recurs throughout life Can occur in any organ Particularly common in bone marrow
Vaso-occlusive crisis…
Clinical presentation Intense pain Localized tenderness Swelling & erythema Febrile episodes Juxta-articlar area = joint effusion Leucocytosis are also common Most patients recover with no complications
Vaso-occlusive crisis…
Plain radiograph Diagnosis is clinical Not useful in acute phase Later: subchondral &
intramedullary lucency & patchy sclerosis
Vaso-occlusive crisis…
MRIRadioisotope scan Very sensitive Not specific (Infarction vs OM) Not routinely used
Vaso-occlusive crisis…
Dactylitis (hand-foot syndrome) Described by Danford Subsequently Xterized by Smith Under 5yrs (typically 6 – 18months) Small bones of hands & feet
Vaso-occlusive crisis…
Dactylitis Clinically; acute, painful swelling Erythema & warmth Most episodes resolve within 2 weeks Epiphyses = premature fusion & shortened fingers
Vaso-occlusive crisis…
Dactylitis Radiological evidence of
new bone (2weeks)
‘Moth-eaten’ appearance bcs of cortical thinning & irregular attenuation of the medullary spaces
Vaso-occlusive crisis…
Dactylitis Histology:
Infarction of the marrow, medullary trabeculae & inner layer of the cortex
Subperiosteal new bone formation
Vaso-occlusive crisis…
Treatment Infection, dehydration, acidosis, hypoxia, cold, IVF & analgesia
Paracetamol NSAIDs Opioid derivatives
Antibiotics
Osteomyelitis 90% of SCD develop OM before 10yrs No bone is exempted Multifocal Precipitated by VOC
Risk factors in SCD Hyposplenism Impaired complement activity Infarcted or necrotic bone
Osteomyelitis
Common organisms Staphylococcus aureus Salmonella (Hodges & Holt, 1951)
Osteomyelitis …
Diagnosis Common mgt dilemma
Failure = life threatening infection Erroneous diagnosis = unnecessary 6wks of antibiotics
Pain, swelling, tenderness & pseudoparalysis Most common sites: Femur, tibia & humerus Often affect diaphysis Features are similar to those of VOC
Osteomyelitis …
Plain radiograph Always first step Not diagnostic May exclude other dxs Bony changes in 2-3wks
Osteomyelitis …
USS Soft tissue disturbance Subperiosteal collection Useful for aspiration
Osteomyelitis …
Bone scan MRI
Osteomyelitis …Treatment Based on organism 3rd generation cephalosporin Ciprofloxacin in older children Drainage Bone drilling
Once AO COM Conservative Rx, until involucrum is formed Sequestrectomy
Septic arthritis
Not common Tends to occur with painful VOC Aetiology as in OM Salmonella arthropathy is very rare
Septic arthritis…
Rx Early aggressive drainage, debridement & splintage A two-week course of IV antibiotic
Osteonecrosis
AVN Most common complication More common in SC > 50% of SCD > 30yrs M:F = 1
Osteonecrosis…
Presentation There may be hx of trauma Pain, limited motion Occasionally with pain at rest May be asymptomatic (shoulder)
Osteonecrosis…
Common sites Femoral heads Head of the humerus Knee joint Small joints of the hands & feet Common to have multiple joints affected Hip: bilateral in >50% Shoulder : 74% have AVN of HOF
Osteonecrosis…
Plain radiographs Mottled attenuation of
the epiphysis Subchondral lucency Flattening/collapse of
the articular surfaces Narrow joint space Articular sclerosis &
osteophyte formation
Osteonecrosis…
MRI Best for early disease Double line sign
Osteonecrosis…
Untreated, 87% of HOF will collapse within 5 years Bed rest & symptomatic Rx: unacceptable Early dx: Core decompression & osteotomy Late dx: Arthroplasty
SCD patients must be cared for in specialized centres with expertise in SCD as they have a very high
incidence of perioperative complications
Osteopaenia & Osteoporosis
Reduced bone mineral density (BM hyperplasia) Common in the vertebrae Vertebral collapse
Osteopaenia & Osteoporosis…
Radiograph Increased radiolucency Prominence of vertebral trabeculae Smooth, biconcave vertebrae ‘Fish-mouth’ vertebrae
Growth disturbance
BM hyperplasia Vertebrae
Ischaemia of the vertebral growth plate
Disturbance of vertebral growth
Characteristic ‘H’ shaped vertebrae
Some develop ‘tower’ vertebra
Growth disturbance…
Long bones Premature closure of
epiphyses Impaired growth of the
long bones
Conclusion SCD prognosis is still poor Orthopaedic manifestations: major cause of morbidity Mgt of its orthopaedic complications is challenging Necrosis & infections are responsible for major
functional impairment Surgery is the mainstay of Rx of these complications While waiting for new genetic therapy for SCD, the
surgeon will treat the complications but should keep in mind that anaesthesia is more risky for these
patients .
References Dgere A, Ndjoko R, Docquier P, Mousny M, Rombouts J. Orthopaedic
complications associated with sickle-cell disease. Acta Orthop. Belg., 2006, 72, 741-747.
Antonio A, Irene R. Bone involvement in sickle cell disease. British J Haemat, 2005; 129:482–490
Michael HH, Gary EF, James SM. Orthopeedic Manifestations of Sickle-Cell Disease. J Bio Med, 1990; 63:195-207
Louis S. Osteonecrosis and related disorders. Apley’s system of orthopaedics and fractures, 9th ed; Hodder Arnold, 2010; 6: 103 – 15.
Archampong EQ, Addo AO. Surgical aspects of the hemoglobinopathies. Principles and practice of surgery including pathology in the tropics, 4th ed; 51: 1015 – 25.
Geraldo B, Elizabeth D, Francisco A. Osteoarticular involvement in sickle cell disease. Review article. Rev Bras Hematol Hemoter. 2012;34(2):156-64