5 Describe A Similar Pathology Flashcards
Outline the radiographic appearance of Paget’s disease
Stage 1: Osteolytic inceased osteoclastic activity → loss of bone density Stage 2: Combined cortical thickening Increased radiopacity lucent areas intermixed extensive repair with fibrotic bone Stage 3: Sclerotic (Ivory) uniform thickening of trabeculae = “ivory” appearance.
You would differentiate this pathology from an idiopathic condition also involving the hip but caused by an interruption to the blood flow to the developing femoral head
State the pathological deformities seen in Legg-Calve-Perthes disease.
– femoral head flatter and enlarged – acetabulum is larger and shallow – femoral neck in shorter and more acutely angled (coxa vara) – greater trochanter is enlarged (1.0 mark per point)
In a much older patient who presents with dull pain you might suspect long standing degeneration as a result of a congenital anomaly. But if there is no history of congenital anomaly, and the femur is enlarged, bowed and warm, you might suspect a metabolic condition known as Paget’s disease
Describe the pathology of Paget’s disease.
Abnormal osteoclasts proliferate Bone resorption outstrips formation Bone replaced with fibrous tissue Destruction and rebuilding eventually occurs simultaneously (1 mark for these point)
Bone increases in size and thickness
Resulting in sclerotic lesion
Thick layers of coarse bone
Increased vascularity and bone marrow fibrosis with intense cellular activity
Increased numbers of large osteoclasts
(Marks can be given for these points if they are mentioned)
You would differentiate this pathology from an idiopathic condition also involving the hip with lateral femoral displacement on plain film radiograph, but which would also include a small femoral capital epiphysis and widening of the medial joint space
Name and describe the four distinct pathological stages of this disease.
Avascular stage
– ossification centre becomes necrotic
2. Revascularisation stage
– resorption of the necrotic bone; replaced by new immature bone cells; remodelling of bone contour
3. Remodelling/repair
– formation and replacement of immature bone cells by normal bone cells; remodelling of femoral head
4. Deformity
– femoral head flatter and enlarged
– acetabulum is larger and shallow
– femoral neck in shorter and more acutely angled
– greater trochanter is enlarged
Describe the cause of medial medical meniscus injuries of the knee
Mechanism of injury:
during internal rotation of femur on tibia with knee in flexion, the femur tends to position the medial meniscus posteriorly toward the centre of knee joint; the posterior part of meniscus is caught between the femur and tibia, & is torn longitudinally when the joint is suddenly extended;
Because Osteomyelitis is an infectious process, inflammation will be contributing to her signs and symptoms.
Describe the blood flow changes, the movement of fluid and cells from the blood to the interstitium, and the mechanisms which cause these changes to occur during acute inflammation
Directly after injury, due to vasoconstriction, transient ischemia takes place. Ischemia may last from a few seconds to a couple of minutes.
This is followed by a progressive, persistent vasodilatation these vascular changes are followed by blood flow changes there is a rapid blood flow due to the vasodilatation. With the dilation of the small blood vessels, a pulsating of the whole capillary bed results (hyperemia) a lot of heat is generated during these processes due to ↑ blood flow Slowing of blood flow then takes place until stasis occurs due to a loss of plasma into the neighbouring tissue as a result of ↑ permeability of vesselsThe WBC (white blood cells or leukocytes) move to the vessel endothelium → margination takes place (pavementing) → leukocytes adhere to the endothelium. The endothelium openings enlarge and allow the leukocytes to pass through by means of pseudopodia and amoeboid movement (leukocyte migration though the endothelium and basement membrane = diapedesis). The leukocytes then migrate through the interstitium to the inflamed area under influence of the released chemical substances (mediators) by means of chemotaxis. The movement of leukocytes and protein rich fluids from intravascular to extravascular space (interstitium) causes swelling and the stretching of the tissue and released chemicals cause pain. Phagocytosis by the leukocytes takes place with the destruction of the toxic agent. Grossly injured cells (tissues) will lose their function and die.
(0.5 to 1 mark for each point)
After examination there is pain on pressure to the proximal fifth metatarsal and on reviewing the radiographs something seems to have pulled away from the bone. Avulsion fracture of 5th metatarsal styloid;
What other type of trauma in the same location should this not be confused with?
Jones’ fracture involves a fracture at the base of the fifth metatarsal which typically extends into the 4-5 intermetatarsal facet; - Jones fracture is located within 1.5 cm distal to tuberosity of 5th metatarsal
What other musculoskeletal condition may be associated with this trauma at the elbow
Describe the cause and clinical manifestations of this condition
Dislocation of the elbow
Classified according to the relationship of the radius and ulna to the humerus (posterior, postero-lateral, anterior, medial, antero-medial). Posterior dislocations are most common, especially in children. Usually associated with fracture. (2marks for these points)
State the articular clinical manifestation of Rheumatoid Arthritis (RA) in the hand
I. usually bilateral and symmetric involvement of proximal interphalangeal (PIP) and metacarpophalangeal (MCP) joints
II. Fingers spindle-shaped due to inflamed PIP joints
III. Subluxation of joints with joint deformities leading to ulnar deviation of fingers (swan neck deformity = hyperextened pip joint and flexed dip joint)
IV. Fixation of joints (Boutonnière deformity = flexed pip joint and hyperextended dip joint)
Describe the pattern (appearance) of a Scaphoid fracture
Often missed. Fracture line transverse in relation to the long axis of scaphoid. The position of the fracture has a bearing on healing and complications. A fracture through the waist (70%), proximal pole (20%), or distal pole (10%)
A possible long term consequence of trauma to this region is a musculoskeletal soft tissue injury affecting a single nerve known as carpal tunnel syndrome.
Describe the clinical manifestations of carpal tunnel.
Caused by compression of the median nerve in the carpal tunnel with direct damage to the nerve or the development of nerve ischaemia
(2 marks)
Clinically manifested by numbness in the lateral three and half digits of the hand. (1.5 marks)
Pain in wrist and hand that worsens at night; (1.5 marks)
Atrophy and weakness of thumb muscles (1.5 marks)
Clumsiness in carrying out fine motor movements (1 mark)
Distressing tingling prominent at night is relieved by rubbing shaking and working the fingers (1.5 marks)
She has some distinctive radiographic changes in the proximal interphalangeal (PIP) and metacarpophalangeal (MCP) joints, such as marginal erosions, uniform loss of joint space and joint deformity.
Describe the pathological characteristics of the inflammatory arthritic condition you suspect.
RF found in blood, synovial fluid and synovial membranes
PMN, macrophages, lymphocytes are attracted to the areas containing RF
Phagocytosis of the immune complex and release of lysosomal enzymes capable of causing destruction of joints
Inflammatory response follows, attracting additional lymphocytes and plasma cells → perpetuation of the condition
As the inflammatory process advances, synovial cells undergo reactive hyperplasia
Vasodilation causes increase blood flow, warmth, redness, swelling in the joint
OR
Development of new blood vessels in synovial membrane → advancement of synovitis
Destructive vascular granulation tissue called a PANNUS extends from the synovium
Inflammatory cells of the pannus have a destructive effect on the adjacent cartilage and bone
Eventually pannus extends into the joint margins causing ↓ joint movement, joint instability, ligamentous laxity, muscle atrophy
Joint destruction is irreversible
