orthopedic pathology (bone pathologies) Flashcards
common issues of bone pathologies
bones too soft
bones too brittle
bones not right shape (mineral content)
tumours
SSx of bone pathologies
bone pain
visible deformity
easily fractured
diagnostic methods for bone pathologies
imaging:
X-ray
Bone scan (nuclear radiography)
**
genetic testing
bone scan (nuclear radiography)
A whole-body bone scan is a nuclear medicine test to check your bones for issues or changes.
You receive an injection of a substance called a radiotracer. The radiotracer collects in areas of irregular activity and highlights these areas on an imaging scan.
It’s painless and safe for most people.
A bone scan is a type of nuclear radiology procedure.
treatments (bone pathologies)
medication
E.g.
Bisphosphonates slow bone density loss
(decrease osteoclast activity; increase osteoblast activity –> esp after menopause)
other Treatment:
Surgery
(removing tumours?
surgically fixing fractures/weak areas?)
osteoporosis
Progressive and systemic metabolic disease of decreasing bone mass/density
Bone breaks down over time and becomes brittle, thin, and breaks easily
osteopenia
Osteopenia
Low bone mass
Precursor to osteoporosis
osteoporosis classifications (primary/secondary)
Primary osteoporosis unrelated to any underlying disease or condition (80-95%)
–> primary = idiopathic / age-related
–> secondary = Secondary osteoporosis due to medication or other conditions
osteoporosis risk factors
Hormonal status (e.g. menopause)
Age (decrease estrogen in women with age)
Ethnicity (caucasian females)
Sedentary Lifestyle
Smoking (decreases estrogen)
Alcohol
Family history
Diet
osteoporosis other risk factors
Depression (hormones)
Weight (hormones)
Medications (steroids, chemotherapy)
Female
High caffeine intake
Malnutrition
Malabsorption (vtitamin d, c, calcium, etc.)
Endocrine disorders (hormones)
osteoporosis SSx
Asymptomatic
Height loss
(compressed vertebrae –> thoracic kyphosis, lumbar hypolordosis, protracted head/neck)
–> note dowager’s hump
Postural changes
–> “
Compression fractures
(compressed vertebrae)
Back pain (sharp with no cause)
–> lumbar vertebrae compression, nerve compression (??)
Fractures
Muscular pain and spasm
–> reflex muscle guarding (?)
osteoporosis Dx
History, physical assessment
Dual-energy X-ray absorptiometry (DEXA):
—> Low levels of x-rays used to measure mineral density
—> Standard x-rays cannot detect small decreases of bone mass
Lab tests
Blood tests:
can help determine levels of minerals and hormones
useful to determine WHY bone density is low
—> WHICH component is affecting bone density
DXA test vs standard X-ray
A DXA scan (bone density test) is a quick, painless way to check your bone health.
It’s similar to a regular X-ray, but measures the strength and mineral content of your bones instead of just taking pictures of them.
“The DXA scanner on the other hand is designed to measure the density of body tissue but does not produce a high-quality picture.”
osteoporosis Tx
Prevention
Critical age between 10 and 30 years
Lifestyle
Decrease alcohol, tobacco, caffeine intake
Increase weight bearing activities
which ages are important to develop good habits for maintaining good bone density throughout life
between 10 and 30 years
osteoporosis medication for treatment
Medication:
Estrogen (hormone therapy)
Calcitonin – inhibits osteoclasts
Bisphosphonates (decrease osteoclast activity, increase osteoblast activity)
Calcium and vitamin D supplements
other important factors
Adequate sunshine (vitamin d)
Diet high calcium, vitamin D and protein
bone tumour types
Tumours can be osteoblastic
—> Excessive bone is laid down
Tumours can be osteolytic
—> Bone is destroyed
benign bone tumours
can be via
bone cells,
cartilage cells,
and fibroblasts
Can cause pathological fracture
Can cause neurological symptoms ( via MASS EFFECT)
pathological fracture define
A broken bone caused by disease, often by the spread of cancer to the bone.
Mass effect define
“It can be used to describe any lesion in the body if it exerts displacement of adjacent structures”
(E.g. benign bone tumours on nerves)
differentiating myositis ossificans vs. bone tumour
Differentiating between myositis ossificans and extraskeletal osteosarcoma is critical.
The zoning pattern of growth in myositis ossificans is an important diagnostic point.
Osteosarcoma displays disorderly growth of atypical hyperchromatic and pleomorphic tumor cells.
benign bone tumours treatment?
Treatment is dependent on symptoms
—> If tumour is compressing adjacent structures, surgery is performed
osteoma (type of benign bone tumour)
Slow growing
Usually asymptomatic
Usually occur on the skull or mandible, but can sometimes be found in the cervical region
osteoma risk factors
Most osteomas have no identifiable cause. A small percentage are present or develop soon after birth.
Others are believed to result from inflammation or trauma.
In rare cases osteomas may be a component of an underlying hereditary disorder.
osteochondroma
Bone tumor with cartilage (chondro) cap
MOST COMMON benign bone tumor
Found in children because they tend to grow at growth plates (cartilage)
Usually asymptomatic
Often an INCIDENTAL FINDING
what is the most common benign bone tumour?
OSTEOCHONDROMA
what population is osteochondroma found in?
Why?
children
@ growth plate (cartilage)
why is osteochondroma generally via “INCIDENTAL FINDING”
Because many osteochondromas do not cause any discomfort or other symptoms, they are often discovered by accident when an X-ray is done for an unrelated reason, such as a traumatic injury.
This is called an incidental finding.
incidental finding define
Incidental medical findings are previously undiagnosed medical or psychiatric conditions that are discovered unintentionally and during evaluation for a medical or psychiatric condition.
enchondroma
Cartilaginous tumor
Arise from growth plate/chondrocytes abnormalities
Usually found in children or young adults
10 – 30 years of age (?)
Fairly common
Usually asymptomatic
—> Found incidentally
“Osteochondromas most commonly occur in the hands and feet, and enchondromas typically involve the iliac crests and metaphyses of long bones.”
osteoid osteoma
Bone tumor
Usually found in children and adolescents
osteoid osteoma clinical presentation
Clinical presentation
—> Classically cause night pain which is relieved by aspirin*
—> Mass effect
—> Risk factor for Fx
osteoma vs osteoid osteoma
“An osteoid osteoma is a benign (noncancerous) bone tumor that usually develops in the long bones of the body such as the thighbone and shinbone.”
osteoma?
“Usually occur on the skull or mandible, but can sometimes be found in the cervical region”
osteoma vs osteoid osteoma (histology)
Different histology than osteoma
Giant cell tumour
(aka OSTEOCLASTOMA)
Thought to be via overproliferation of osteoclasts
Occurs when growth plate is closed; therefore typically seen in early adulthood (20-30 years of age)
Osteolytic bone tumour
osteoclastoma surgical treatment (?)
Traditional surgical treatments have mostly employed intra-lesioned resection and bone cement reconstruction;
however, these may cause unexpected damage around neurovascular structures.
resection define
the process of cutting out tissue or part of an organ.
bone cement?
Bone Cement Injection?
This procedure is used to help fill open or weak spaces in bones.
aneurismal bone cyst
aneurism = “widen out” / dilation/bulge
cyst = “bladder”
Expansile and osteolytic tumour
Primarily seen in children and adolescents
Idiopathic
aneurismal bone cyst, primarily seen in
children and adolescents
more about aneurysmal bone cysts
Aneurysmal bone cysts are non-malignant, tumor-like, vascular lesions comprised of blood-filled channels.
Although they can occur in any bone, they are most common in the femur, tibia, and vertebrae. [1]
Their expansile nature may result in pain and inflammation, and disruption of joints and growth plates
Fibrous dysplasia
Congenital abnormality in osteoblastic differentiation and maturation
Leads to progressive replacement of normal bone with fibrous tissue (scar-like tissue)
Defect is usually localized to one bone
MALIGNANT BONE TUMOURS
Have the capacity to metastasize
Often do so aggressively by invading locally and destroying adjacent tissues
Less common than benign tumours
Usually associated with constant and severe pain or night pain
Skeletal Metastasis
Most common malignant tumours of the skeleton (via metastasis from tumour located elsewhere in body)
70% of all malignant bone tumours
—> Breast, prostate, lung and kidney cancers account for 80% of osseous metastases
80% of malignant tumours are axial tumours
what cancers account for 80% of all osseous metastases?
Breast, prostate, lung and kidney cancers
what percentage of malignant tumours are axial tumours
80% of malignant tumours are axial tumours
clinical presentations of malignant bone tumours
fractures, cachexia, bone pain
cachexia
weakness and wasting of the body due to severe chronic illness.
kakos = bad
hexis = habit
a typical pattern (not always the case)
(where benign vs malignant tumours are)
generally malginant bone tumours are @ axial skeleton
& benign bone tumours are @ appendicular skeleton
multiple myeloma
Most common primary malignant bone tumor
Characterized by proliferation of malignant plasma cells and a subsequent overabundance of abnormal proteins and infiltration of red bone marrow.
Occurs in individuals over age 40.
—> 70% are between 50 – 70 years of age.
primary vs secondary tumour
secondary = via metastasis
primary = not via metastasis
mutiple myeloma age
Occurs in individuals over age 40.
—> 70% are between 50 – 70 years of age.
why called mutiple myeloma
A cancer cell or malignant plasma cell is called a myeloma cell.
Myeloma is called “multiple” because there are frequently multiple patches or areas in bone marrow where it grows.
multiple myeloma SSx
Bone pain
Pathologic fractures
Anemia (@ bone marrow)
Recurrent infection (@ bone marrow, so WBC)
Proteinuria
Renal failure
why renal failure and proteinuria in multiple myeloma?
Multiple myeloma (MM) is a type of blood cancer that affects white blood cells called plasma cells. These cells help to fight infection.
In MM, the abnormal plasma cells produce abnormal proteins that can bind to other proteins in the kidneys. This can result in kidney damage.
why proteinuria?
fenesterated capillaries in kidneys damaged
proteins leak through
osteosarcoma
Second most common primary malignant bone tumor
Typically seen in young patients (10-20 years of age)
most common vs second most common PRIMARY malignant bone tumour
multiple myeloma = most common
osteosarcoma = second most common
also considered a blood tumour?
multiple myeloma (b/c @ RBM – related to blood)
osteosarcoma clinical presentation
Clinical presentation:
—> Pain is common
—> Soft tissue mass and swelling
—> Pathological fracture
chondrosarcoma
Cartilaginous tumor
Typical age group is 30 – 50 years of age
chondrosarcoma clinical presentation
Clinical presentation:
—> Pain
—> Palpable mass
—> Pathological fracture
Ewing’s Sarcoma
Composed of undifferentiated bone marrow cells
Occurs in MALES aged 10-20
Found in the diaphysis of long bones
—> Poor prognosis
(high mortality)
Ewing’s Sarcoma – undifferentiated bone marrow cells?
Ewing sarcoma is a type of tumor that forms from a certain kind of cell in bone or soft tissue.
Undifferentiated small round cell sarcoma may also form in the bone or soft tissue.
A genetic condition may increase the risk of Ewing sarcoma and other sarcomas.
“This biopsy shows an undifferentiated small round cell sarcoma involving bone with focal areas of necrosis”
recall low level of differentiation =
recall low level of differentiation = high level of malignancy
Fibrosarcoma
Rare malignant tumor of fibroblasts and collagen
—> Can be found in other soft tissues as well
Occurs in people 30-60 years of age
Fibrosarcoma presentation
Usually found around the knee
Localized pain and swelling with long duration of symptoms
Malignant Fibrous Histiocytoma
Composed of mesenchymal stem cells
Very aggressive tumour
—> Commonly metastasizes
Most commonly found in people 50-70 years old
Hodgkin’s Lymphoma
Type of lymphoma that typically spreads through predictable lymphatic pathways
Note:
Presence of Reed-Sternberg cells, which are abnormal B cells
—> Reed-Sternberg cells are pathognomonic
Hodgkin’s Lymphona – clinical presentation
Painless lymphadenopathy
Night sweats
Weight loss/cachexia
recall lymphadenopathy
Lymphadenopathy refers to the swelling of lymph nodes which can be secondary to bacterial, viral, or fungal infections, autoimmune disease, and malignancy.
Hodgekin’s lymphoma prognosis
90% curable if detected early
late detection = worse prognosis (?)
osteomyelitis
Inflammation of bone caused by infectious microorganism, usually bacteria (also could be fungus, parasite, virus)
Acute – initial infection
Chronic – delayed treatment, relapse, delayed healing, prolonged infection
osteomyelitis etiology
Most common - staphylococcus aureus (RECALL ALSO MOST COMMON CAUSE FOR INFECTIOUS (septic) ARTHRITIS)
Also streptococcus, pneumococcus, Haemophilus influenzae, E. coli, salmonella
Often polymicrobial
From infected wounds, blood, open wounds, surgery
osteomyelitis, Risk factors
(weakened IS)
Chronic illness (weaker IS)
Steroids use or immunosuppressive drugs (weak IS)
Age (weaker IS)
Malignancy (weak IS)
Malnutrition (weaker IS)
osteomyelitis SSx
Varies depending on host age and health status and on organism involved
Can include:
—> Fever, severe pain
—> Edema, erythema, tenderness
—> Low grade fever
erythema vs hyperemia (??)
Hyperaemia – increased blood in a part, resulting in distension of the blood vessels.
Erythema – a redness of the skin occurring in patches of variable size or shape.
Osteomyelitis, Dx, Tx
Diagnosis:
History
X-ray
Bone scan
Cultures
Treatment:
Antibiotics
Surgery
bone marrow culture (test?)
Bone marrow culture is an examination of the soft, fatty tissue found inside certain bones. The bone marrow tissue produces blood cells.
This test is done to look for an infection inside the bone marrow.
It is often done to diagnose prolonged fever that remains unexplained after other tests.
osteomyelitis why surgery?
Surgery. Depending on the severity of the infection, osteomyelitis surgery may include one or more of the following procedures:
Drain the infected area.
Opening up the area around your infected bone allows your surgeon to drain any pus or fluid that has accumulated in response to the infection.
