Skeletal Imaging

1. INTRODUCTION TO
SKELETAL IMAGING
Muhammad Bin Zulfiqar
PGR II SIMS/SHL
New Radiology Department

2. Overview of Skeletal system
•Total bones 206
•Skull bones 22
•Ear bones 6
•Throat Bone 1
•Thorax 25
•Vertebral column 24
•Shoulder girdle 4
•Upper limb 60
•Pelvis 4
•Lower Limb 60

4. Imaging Modalities for Skeletal
System
•Plain Radiographs(main focus)
•Nuclear Scintigraphy
•Contrast Examination
•Ultrasound
•Computed Tomography
•Magnetic Resonance Imaging

5. Major Diseases of Bone
 Trauma
 Congenital
 Infections
 Tumors
 Metabolic, Endocrine, Nutritional
 Bone Dysplasia
 Inflammatory Diseases(R.A.)
 Associated soft tissues abnormalities

6. Skeletal Anatomy and Physiology
Skeletal Development
 Intramembranous Ossification
 Enchondral Ossification
Bone Structure
 Epiphysis – ZPC – Metaphysis
– Diaphysis
 Cortex – Medulla – Periosteum
– Endosteum
Bone Metabolism
 Bone mineral - Hormones

7. Anatomy

8. Anatomy

9. Anatomy

14. Approach to skeletal imaging
Preliminary Analysis
• Clinical data
• Number of lesions
• Symmetry of lesions
• Determination of Systems Involved

15. Analysis of The Lesions
Skeletal Location
Position Within Bone
Site of Origin
Shape
Size
Margination
Cortical Integrity

16. Analysis of The Lesions
Behavior of Lesions
• Osteolytic Lesions
• Osteoblastic Lesions
• Mixed Lesions
 Matrix
 Periosteal Response
• Solid Response
• Laminated Response
• Spiculated Response
• Codmans’Triangle

17. Radiologic Predictor Variables
 Supplementary Analysis
 Other imaging Procedures
 Laboratory Examination
 Biopsy
 Soft Tissue Changes

18. TRAUMA
Fracture and Dislocation
The radiographs should be made
 Include at least one joint
 Preferably two joints
 Two position AP – LAT

19. TRAUMA
Time intervals between Radiographic Study
 Initial Diagnostic study
 Post reduction and post immobilization
 One or Two weeks later, if position has
changed
 After approximately six eight weeks for
Primary callus
 After each plaster cast or traction change
 Before final discharge of patient

20. TRAUMA
Types of Fracture
 Closed fracture
 Does not break the skin or communicate
with the outside environment
 Simple fracture
 Open fractur
 Penetrates the skin over fracture site
 Compound fracture

21. TRAUMA
Comminuted fracture
 Two or more bony fragments have separated
 Non Comminuted fracture
 Penetrates completely through the bone
 Avulsion fracture
 Tearing away of a portion of the bone
 Impaction fracture
 Bone is driven into its adjacent segment

22. TRAUMA
 Incomplete Fracture
 Broken only one side of the bone
 Greenstick (Hickory Stick) fracture
 Torus (Buckling) fracture
Fracture Orientation
 Oblique fracture
 Commonly occurs in the shaft of long
tubular bone
 45 to the long axis of the bone

23. Fractur

24. Fracture

25. TRAUMA
 Spiral fracture
 Torsion, coupled with axial compression
and angulation
 Transverse fracture
 Run at a right angle to the lonh axis
 Uncommon through healthy bone
 Pathologic fracture

26. Fracture

27. TRAUMA
Spatial Relationships of Fracture
 Alignment
 Position of the distal fragment in relation
to the proximal fragment
 Apposition
 Closeness of the bony contact at the
fracture site
 If the ends are pulled referred to as
Distraction

28. Fracture

29. TRAUMA
 Rotation
 Twisting forces on a fractured bone along
its longitudinal axis
Traumatic Articular Lesions
 Subluxation
 Dislocation
 Diastasis
Epiphyseal Fractures
 Salter-Harris Classification

30. Salter - Harris

31. Dislocation

32. TRAUMA
Fracture Healing
 Main steps in fracture healing
 Formation of hematoma
 Organization of hematoma
 Formation of fibrous callus
 Replacement of fibrous callus by
primary bany callus
 Absorption primary bany callus
Transformation to secondary bony callus
 Remodeling

33. TRAUMA
Complication of Fractures
 Immediate complication
 Arterial injury
 Compartment syndrome
 Gas gangrene
 Fat embolism syndrome
 Thromboembolism

34. TRAUMA
 Intermediate complication
 Osteomyelitis
 Myositis ossificans
 Synostosis
 Delayed union
 Delayed complication
 Osteonecrosis
 Osteoporosis
 Non union – Mal union

35. Myositis Ossificans

36. INFECTION
Suppurative Osteomyelitis
 General Consideration
 Systemic or Local infections
 Immunosuppresed patients, alcoholics,
newborns, and drug addicts are predisposed
 Antibiotics have significatly reduced the
sepsis-related mortality

37. INFECTION
 Etiology
 Staphylococcus aureus causes 90%
 Pathway for the spread
 Hematogenous
 Contiguous
 Direct Implantation
 Postoperative

38. INFECTION
 Radiologic Features
 Bone scan are the earliest means of
diagnosis
 Radiographic latent period for plain film
 10 days for extremities
 21 days for spine
 Soft tissue alteration : elevated fat planes,
obliterated fat planes, increased density.

39. INFECTION
 Bone changes :
 Moth-eaten bone destruction
Usually metaphyseal in origin
 Periosteal new bone formation
Solid – Laminated – Codman’s Triangle
 Sequestrum
 Involucrum
 Joint space destruction (ankylosis)

40. 0steomyelitis

41. Osteomyelitis

42. INFECTION
Septic Arthritis
 General consideration
 Single joint involvement in the rule
 Most common route is hematogenous
or direct traumatic implantation
 Etiology
 Most frequently is Staphylococcus Aureus

43. INFECTION
 Radiologic Features
 The knee and hip are the most common
sites
 Joint effusion leads to distortion of the
fat folds
 Positive Walden storm's sign
 Rapid loss of joint space
 Bony ankylosis

44. INFECTION
Nonsuppurative osteomyelitis
(tuberculosis)
 General Consideration
 Found in patients such as prepubertal
children, debilitated geriatric, silicosis,
AIDS sufferers, Lymphoma patients,
Alcoholics, corticosteroid and drug abusers

45. INFECTION
 Etiology
 Mycobacterium tuberculosis
 Two mode of spread
 Inhalation
 Ingestion

46. INFECTION
 Radiologic Features
 Spinal tuberculosis is most common at L-I
 Early sign for spine are :
 Lytic endplate destruction
 loss of disc height
 Anterior “ gouge defect “
 Paraspinal swelling

47. INFECTION
Advanced sign for spinal involvement are:
 Vertebral body collapse
 Gibbus formation and obliteration of the
disc
 Tubercular arthritis is common in the hip and
knee
 Uniform joint space narrowing, early destruction
of the subchondral cortex, “moth-eaten” bone
destruction and juxtaarticular osteoporosis are
the cardinal sign of tubercular arthritis

48. Tuberculosis

49. Tuberculosis

50. TUMORS AND TUMORLIKE
PROCESSES
METASTATIC BONE TUMORS
PRIMARY MALIGNANT BONE TUMORS
 Multiple myeloma
 Osteosarcoma
 Ewing’s Sarcoma
PRIMARY QUASIMALIGNANT BONE
TUMOR
 Giant Cell Tumor

51. TUMORS
PRIMARY BENIGN BONE TUMORS
 Osteochondroma
 Osteoma
 Bone island
 Osteoid osteoma
 Simple bone cyst
 Aneurysmal bone cyst

52. TUMORS
Metastatic Bone Tumors
 General Consideration
 The most common malignant tumors
 CNS tumors and basal cell Ca rarely
 Life threatening complication
 Incidence
 70% are metastatic, 30% are primary
 In females 70% from breast Ca
In males 60% from prostate Ca

53. TUMORS
 Radiologic Features
 Technetium bone scan
 80% of all metastases are located in the
central or axial skeleton
- Spine and Pelvis being a most common
 Alteration in bone density and architecture
 75% osteolytic, moth eaten or permeative
 15% osteoblastic
 Periosteal response is rare

54. Metastatic

55. TUMORS
Primary Malignant Bone Tumors
 Multiple Myeloma
 Bone scan are cold
 Gross Osteoporosis may be the only early
sign
 Punched out lesions
 Vertebra plana or wrinkled vertebra
 Preservation of pedicles

56. Multiple Myeloma

57. Multiple Myeloma

58. TUMORS
 Osteosarcoma
 75% of cases occurs in the 10 to 25 age
 Metaphysis of the distal femur, proximal
humerus are the most common sites
 Permeative or ivory medullary lesion in
metaphysis of a long tubular bone
 A sunburst or sunray periosteal response
 Cortical disruption with soft tissue mass
formation
 Sclerotic – Lytic – Mixed lesion

59. Osteosarcoma

60. Osteosarcoma

61. TUMORS
 Ewing’s Sarcoma
 Most cases occur in the 10 – 25 age range
 May mimic infection
 Diaphyseal permeative lesion
 Femur, tibia and fibula
 Onion skin periosteal response
 Most common primary malignant bone
tumor to metastasize to bone

62. Ewing’s Sarcoma

63. TUMORS
Primary quasimalignant bone tumor
 Giant cell Tumor
 Osteoclastoma
 20-40 years is the usual age range
 Distal femur, proximal tibia
distal radius, proximal humerus
 Metaphysis and extend to subarticular
 Radiolucent, eccentric
 Soap Bubble appearance

64. Giant Cell Tumor

65. TUMOR
Primary Benign Bone Tumors
 Osteochondroma
 Painless and hard mass near a joint
 Humerus, tibia, femur, ribs
 Two types : - sessile
- pedunculated
 Coat hanger exostose – cauliflower mass
 The cortex and spongiosa blend
imperceptibly

66. Osteochondroma

67. TUMOR
 Osteoma
 A rise in membranous bones
 Sinuses – frontal, ethmoid
Mandible
Skull bones
 Homogenously opaque

68. Osteoma


69. TUMOR
 Bone Island
 Epiphyseal, metaphyseal
 Medullary
 Round – oval : Long axis oriented
Smooth or radiating border
Opaque
Normal adjacent cortex
May change size

70. TUMOR
 Osteoid osteoma
 Consists a nidus, that usually 1 cm or less
 Target calcification
 Most common location is in the cortex
 Radiolucent nidus surrounded by perifocal
reactive sclerosis

71. Osteoid Osteoma

72. TUMOR
 Simple Bone Cyst
 Expansile radiolucent
 Proximal humerus, femur, calcaneus
 No periosteal reaction
 Pathologic fracture
 Aneurysmal Bone Cyst
 Some lesion may reach 8 – 10 cm
 Cortical ballooning “ blown out app”

73. Aneurysmal Bone Cyst

74. Aneurysmal Bone Cyst

75. ARTHRITIC DISORDERS
Degenerative Disorders
 Degenerative Joint Disease
 etc
Inflammatory Disorders
 Rheumatoid Arthritis
 etc
Metabolic Disorders
 Gout
 etc

76. ARTHRITIC
 Degenerative Joint Disease
Osteoarthritis – Osteoarthrosis
 Asymmetric distribution
 Non uniform loss of the joint space
 Osteophytes
 Subchondral sclerosis
 Subchondral cyst
 Loose bodies
 Subluxation

77. Osteoarthrosis

78. ARTHRITIC
 Rheumatoid Arthritis
 Generalized Connective tissue disorder
 Highest incidence among the 40 – 50 year
 Symmetric peripheral joint pain and swelling
 Early : - Soft tissue swelling
Marginal erosions
Osteoporosis - Periostitis
Loss of joint space
Late : - Ankylosis
Deformities

79. Rheumatoid Arthritis

80. Rheumatoid Arthritis

81. ARTHRITIS
Gout
 Disorder of purin metabolism
 Deposits of Sodium monourate crystals
into cartilage, synovium, periarticular
and subcutaneous tissues
 Dense soft tissue Tophi, preservation
of joint space, Bone erosions (marginal
periarticular) “overhanging margin sign”
 Metatarsophalangeal joint

82. Gout

83. QUESTIONS

84. THANK YOU