A triangular area of new subperiostial bone created when a lesion, often a tumor, raises the periostium away from the bone.

A clinical charactaristic of Osteosarcomas.

Bone disease,

cholestatic disorders (obstructive jaundice or interhepatic biliary disease)

Hard notdules or enlargements of the DIP joints of the fingers.

Hallmarks of Osteoarthritis.

Non-collagenous protien found in bone and dentin.

Secreted soely by osteoblasts.

Is itself pro-osteoblastic (bone builders)

Thought to help in metabolic regulation, bone mineralizationa nd Ca2+ ion homeostasis.

Vit D deficiency in adults

Results in a shrotage or loss of calcium salts causing bone to become soft, flexible, brittle and deformed.

Can be related to liver dz, cancer, or other issues with vit D metabolism.

Charactarized as a significant ↓ in the bone mineral density (BMD) as measured by standard deviations relative to normal.

*When BMD is T= -1 to -2.5 a person is osteopenic.

If T<-2.5 the person is osteoperotic.

Inflamed synovial granulation tissue.

Seen in chronic RA*

aka tuberculous spondylitis

A combined infection (osteomyelitis) of the vertebrae and interverterbral joint spaces caused by miliary/dissiminated TB (typically hematogenous spread).

Can result in spinal deformity and/or perminant neurological deficits.

A fragment of necrotic bone that has become separated form the surrounding tissue.

Is considered a primary sequestrum if it is still firmly attached to its tissue of origin, secondary if loosely attached and tertiary if detached but remains in place.

Trophus

A deposit of sodium biurate (precipitated sodium monourate crystals) depositied near a joint in the ear or elsewhere in pt with gout.

Appear on imaging as a white, chalky mass.

An immovable joint with fivrous CT or catilage bw the bone surfaces and no joint cavity.

Incl: synchondrosis (hyline cartilage connects 2 bones),

Suture (rigid joint, as in the skull bones), or

Syndesmosis (slightly movible articulation where 2 bones are attached by an intraosseous ligament (radiocarpal joint)

Central Core Disease

Congenital myopathy

Demonstartes a loss of mitochondria and other organelles form the central portion of Type I muscle fibers.

Charactarized by weakness and hypotonia but infants w this dz do become mobile.

Congenital Myopathy

Demonstrates tangles of small, rod-shaped granules, mostly in type I fibers.

Wide clinical variation from mild and non-progressive to severe weakness causing death due to respiratory failure.

A mitochondrial myopathy

Exibits non-Mendelian, exclusively maternal mode of inheritance

Charactarized clinically by opthamoplegia (EOM paralysis), pigmentary retinopathy, heart block, cerebellar ataxia.

Ragged red muscle fibers

Decrease in bone mass with BMD<-2.5 standard deviations from the mean

Caused by impaired synthesis, ↑ resorption or both.

A metabolic bone dz typically dx by DEXA scan and diffuse radiolucency of bone on XR.

[Ca2+] and [PO4-] are normal

[Alkaline phosphatase] may be ↓

Bones are not adequate for weight bearing resuting in fractures (commonly compression fractures of the vertebrae leading to kyphosis and shortened stature)

Clinically associated with low estrogen (postmenopausal women), inactivity, hypercorticism, hyperthyroidism, calcium deficiency.

What disorder can present with "Brown Tumor"?

von Recklinghausen Disease of Bone

(osteitis fibrosa cystica)

aka Osteitis fibrosa cystica

↑ serum [Ca2+], ↓ [PO4], ↑ [Alkaline Phosphatase]

Caused by 1º or 2º hyperparathyroidism.

Charactarized by widespread osteolytic lesions.

May manifest as "Brown Tumor" of bone, cystic spaces lined by multinucleated osteoclasts filled with vascular fibrous stroma, often with hemorrage giving it its brown discoloration.

XR shows diffuse radiolucency (mimics osteoperosis)

False

In rockets there is ↓ calcification but an ↑ accumulation of osteoid which thickens the epiphyseal growth plates and causes other skeletal deformities.

Thinning and softening of the occiptial and parietal bones of the skull.

Seen in children with Rickets

What does it mean when a pt has late closing of the fontanelles?

Fontanelles are the soft spots on a neonates skull which fuse after birth.

In children with rickets, this fusion is delayed, possibly leading to cranial abnormalities.

A Rachitic Rosary is a thickening of the costochondral juctions resulting in a string-of-beads-like appearance.

Seen in children with rickets.

Harrison's Groove is a depression along the line of insertion of the diaphragm into the rib cage.

It appears in children with rickets.

True

Spinal deformities caused by skeletal weakness can cause decreased height and stooped posture in children with rickets.

=Padget Disease of Bone

Most common in the elderly, unknown etiology (possible role played by viruses)

↑ activity of both osteoclasts and osteoblasts causes abnormal bone architecture and severe bone deformities.

Bones commonly involved are the spine, pelvis, calvarium, femur and tibia. Can involve one or many bones (mono or polyostotic).

Manifest clinically by a marked ↑↑↑ in serum alkaline phosphatase (blast activity) but with normal serum Ca2+ and phosphorous.

False

Padget Dz is charactarized by a marked ↑ in serum alkaline phosphatase but normal serum Ca and phosphorous.

1) Osteolytic Phase: Osteoclastic resorption predominates

2) Mixed Phase: activity of both osteoclasts and osteoblasts, new bone formation leads to a charactaristic mosaic pattern.

3) Late Phase: bone density is ↑, trabeculae are thick and the mosaic pattern is prominent.

Bone pain (resulting from fractures, though thick the bone lacks strength and is prone to micro and macrofractures)

High-output Cardiac failure (AV shunts within highly vascular early lesions)

Hearing Loss (narrowing of the auditory canal or involvement of the small bones of the ear)

Osteosarcoma (this is the one instance where osteosarcoma affects older people, is generally a tumor of younger people).

Painful subperiostial hemorrage

Osteoporosis (esp at the metaphyseal ends of bones)

Failure of the Epiphyseal cartilage to be replaced by osteoid.

Achondroplasia

Autosomal Dominant

Mutation in the fibroblast growth factor receptor 3 (FGFR3) gene.

Charatarized by normal trunk and head but short, thick extremities.

Bones are short and thick and fail to elongate with bony sealing off of the area bw the epiphyseal plate and the metaphysis. Narrow growth plates.

Monostotic: Solitary lesions that are often asymptomatic but can result in sponaneous fractures with swelling and pain, deformity is possible.

Polyostotic: Multiple sites are involved, can be associated with severe deformity.

Polyostotic fibrous dysplasia, Precocious puberty, cafe-au-lait spots, and short stature.

Occurs in very young girls.

Which of the following is not a charactaristic site of aseptic necrosis?

-Tibia

-Fibula

-Navicular Bone

-Femur

Fibula is not.

All of the other sites are typical locations for infarction leading to aseptic/avascular necrosis of bone.

Trauma/Embolism

Includes those due to thrombosis, decompression syndroem (the bends) and SSA.

Aseptic necrosis of the navicular bone

(tarsal bone of the foot)

Collagen

Several different gene mutations can cause these defects but failure to properly produce collagen results in generalized CT abnormalites affecting the teeth, skin, eyes, and bones.

Autosomal Dominant

This type is charactarized by multiple childhood fractures and blue sclerae.

Another name for Osteopetrosis/Marble Bone Dz

False

Caused by the failure of osteoclast activity.

Accompanied by greatly ↑ bone density but bones are weak resulting in multiple fractures.

Also associated with anemia, deafness, blindess, and CN involvement because of narrowing of the foramina.

Autosomal Recessive varient is typically fatal in infancy.

Autosomal Dominant form is less severe.

What is the most common cause of Pyogenic osteomyelitis in neonates?

In children? In Adults? In SSA pt? In IV drug users?

In neonates: GBS or E. coli

In Children: Staph aureus (hematogenous spread)

In Adults: a complication of compound fractures or surgery, no one agent.

In SSA pt: Salmonella

In IV drug users: Psudomonas

Pyogenic infections of bone most often initially involve the metaphysis.

The distal end of the femur, proximal end of the tibia and proximal end of the humerus.

Acute stage (may resolve with abx)

May progress to involve vasculature with pyogenic exudate→ ischemic necrosis of bone and marrow.

Necrotic bone=Sequestrum acts as a foreign body and a locus for persistent infection.

Subperiostial dissection by pyogenic exudate may further impari blood supply, rupture into surrounding tissues and form sinuses (even draining through the skin).

Involucrum=a sleeve fo new bone forms around the sequestrum.

May be walled off by surroundign granulation tissue forming a Brodie Abscess.

True

Secondary reactive systemic amylodisis may complicate pyogenic osteomyelitis.

A subacute osteomyelitis.

A wall of granulation tissue walls off the infection within the bone.

May present as an abscess draining through the skin.

Tuberculous osteomyelitis of the vertebrae.

Vertebrae can collapse leading to spinal deformity.

Vertebrae (Pott Disease)

Hip

Femur

Tibia

Bones of the hands and feet

Histiocytosis X

Birbeck Granules are tennis reacket-shaped cytoplasmic structures which are charactaristic of the proliferative histiocytic cellss of this dz.

 A group of disorders charactarized by the proliveration of histiocytic cells that closely resemble epidermal Lagerhans cells with Birbeck granules and distinctive surface antigens.

There are several varient forms of this disease but the above holds true for each form.

Acute disseminated Lagerhans Cell Histiocytosis.

An aggressive, typically fatal, disorder of infants and small children.

Charactarized by hepatosplenomegly, lymphadenopathy, pancytopenia, pulmonary involvement, and recurrent infections (as a result of widespread histiocytic proliferation).

1) Skull Lesions

2) Diabetes Insipidus

3) Exopthalmos (caused by orbital invovement)

Chronic, Progressive Histiocytosis

Typically presents before age 5, better prognosis than Letterer-Siwe.

Charactarized by histiocytic proliferation mixed with inflammatory cell infultration within the bones particularily in the skull, liver, spleen and other tissues.

Manifests with the Classic Tirad: Skull lesions, Diabetes insipidus and exopthalmos (orbit involvement).

The form of histiocytosis X with the best prognosis of the group (fatalaties rare).

Charactarized by histiocytic proliferation mixed with inflammatory cells (ordinary macrophages, lymphocytes and lots of eosinophils).

Can present as a solitary bone lesion. Extraskeletal involvement is typically limited to the lung.

Osteosarcoma, chondrosarcoma and Ewing Sarcoma

*Excludes metastasis to bone which are more common than primary bone tumors*

aka Osteochonndroma

One of the most common benign tumors of bone.

A cartilage-capped subpareisotial projection from the bone surface.

Typically occur 'about the knee' in males < 25 yo

Multinucleated giant cells and fibrous stroma.

Oval or spindle-shaped cells intermingled with the giant cells.

Most often on the epiphyseal end of long bones (typically about the knee).

Although benign, is a locally aggressive tumor that often recurs after removal.

Multiple Familial Osteochondromatosis

Benign tumor of bone, relatively rare.

An intramedullary cartilaginous neoplasm typically affecting the bones of the hands and feet.

Benign bone tumor.

Neoplastic proliferation of osteoid and fibrous tissue typically occuring about the knee in males <25 yo.

True

Osteosarcomas are tyically found in males, 10-20 y/o about the knee.

It is the most common primary malignant tumor of bone.

Bone pain

Swelling, occasionally a pathological fracture.

Serum Alkaline phosphase is very high (2-3x normal)

Codman Tirangle with a Sunburst pattern on XR***

Yes, this is a highly aggressive tumor with early hematogenous spread.

To the Lungs, Liver, and Brain.

Yes

Paget dz pt, those who have recieived ionizing radiation, had bone infarcts or have Familial Retinoblastoma are more prone to developing osteosarcomas.

False

This malignant bone tumor has a  peak incidence in men aged 30-60.

Malignant cartilaginous tumors with peak incidence in men 30-60 years old.

Can arise as a primary tumor or from transformation of a preexisting cartilagenous tumors (especially multiple familial osteochondromatosis or multiple endochondromatosis)

True

These bone tumors actually have a morpholgical resemblance to malignant lymphomas.

Extremely malignant with early metastases.

However, responds well to chemo.

Boys < 15 y/o

Most often in the long bones, scapula, ribs and pelvis.

What genentic lesion is charactaristic of Ewing Sarcoma?

What other type of tumor shows this lesion?

Ewing Sarcoma is charactarized by a 11;22 chomosomal translocation*

This translocation is identical to that found in Peripheral Neuroectodermal Tumors (PNETs, soft tissue neoplasms of neural crest origin).

Acute Osteomyelitis

Similar pain.

T/F: RA most commonly appears in women aged 55-65

False

Younger!
Most commonly in women aged 20-50 yrs.

~80%

RF is an IgM (usually) Ab with anti-IgG Fc domain specificity.

False

RF is highly charactaristic of (80% have it) but not specific for RA (70% of pt with Sjogrens are also RF+)

Synovitis (inflammation of the synovial membrane) is the most charactaristic manifestation of RA.

Early changes incl acute inflammatory reactions at the joint site with edema and inflammatory inflitrate (neutrophils, lymphocytes, plasmacells).

Hyperplasia and hypertorphy of the cllls of the synovial lining lead to the formation of finger-like villi.

Pannus (granulation tissue) extends ove the articular cartilage and destructive inflammation ensues.

Pannus is granulation tissue that extends over articulate cartilage in RA.

Extension of pnnus to subchondral bone results in the characatristic erosion and cyst formation of RA.

This can lead to deformation of cartilage and bone.

True

Rheumatoid nodules develop in approx 1/3 of RA pt.

PIP and metacarpophalangeal joints of the hands are frequent sites.

Any joint has the potential to be involved though the small joints of the hands and feet as well as the knees are commonly invoved.

Episodic changes include fever, malaise, anorexia, fatigue and myalgia.

Other manifestations include pleural and pericardial effusions, anemia of chronic dz, vasculitis, lymphadenopathy, secondary reactive amylodosis and neurological changes.

RA varient.

Sjogren Dz + RA

RA syndrome

Splenomegly + Neutropenia + RA

Juvenile ideopathic RA

Often preceeded or accompanied by generalized lymphadenopathy, hepatospnelomegly, and acute onset with fever.

Seronegative form of arthritis

Charactarized by absence of RF and involvement of the peripheral and sacroilial joints*

A seronegative arthritis with a high association to HLA-B27 haplotype (up to 90% of pt have it)

Chronic condition affecting the spine and sacroiliac joints which can lead to rigidity and fixation of these joints due to bone fusion (ankyosis)

A seronegative arthritic syndrome.

Charactarized by urethritis, conjunctivitis and arthritis.

True

There is a form of arthritis associted with IBS and other inflammatory bowel diseases (ulcerative colitis, Crohn's Dz). Can be accompanied by peripheral arthritis or ankylosing spondylitis.

Osteoarthritis (OA)

The most common form of arthritis

A degenerative, non inflammatory dz charactarized by degeneration of articular catilage acoompanied by new formation of bone subchondrally and at the margins of affected joints.

Osteoarthritis is the most common form of arthritis.

It typically affects older individuals (50+yrs) with women having a higher incidence than men.

Primary OA has no known cause and many factors are likely to be at work.

Secondary OA occurs in joints damaged by known mechansms such as mechanical trauma, metabolic disorders (ochronosis=homogentisic acid deposition) and inflammatory disorders.

Osteophyte=Bone spur

Commonly form at the perimeter of the articular surface and at points of ligament attachement to bone.

Associated with Osteoarthritis (OA)

XR finding in pt with OA

Fragments of separated cartilage and chunks of osteophyte (bone spur) that have broken off and are floating in the synovial fluid.

Gout

(Arthritis of metabolic origin)

Trophi are located about joints, the helix/antihelix of the hear and the achilles tendon.

Consist of urate crystals in a protein matrix surrounded by fibrous CT, all demostrating a foreign body giant cell rxn.

Gout

Marked by an intense inflammatory reaction beginning with opsinization fo urate crystals by IgG followed by phagocytosis by neutrophils and eventually bh the release of proteolytic enzymes and inflammatory mediators from phagocytic cells.

Inflammatory response leads to painful acute arthritis and bursitis.

Rapidly declining renal function in gout pt caused by interstital deposition of urate crystals causing obstruction of the collecting tubules.

Made worse by the formation of urate and calcium stones.

False

Urate crystals are negatively bifringent under polarized light. This means they appear yellow when their long axis is parallell to the light.

Pseudogout (calcium phosphate) crystals appear blue when their long axis is parallel to the light (positive bifringence)

Primary Gout is due to hyperuricemia without evident cause (is the most common form of gout, MC in middle aged males)

Secondary Gout is much less common, hyperuricemia with known cause (leukemia, multiple myeloma, renal dz w dec excretion of urate, Lesch Nyhan)

Secondary gout

Hyperurecemia with severe neurologic manifestations (self-mutilation) due to X-linked hypoxanthine guanine phosphoribosyltransferase (HGPRT) deficiency.

aka psudogout

Same clinical presentaiton as gout but the crystals are Calcium pyrophosphate dihydrate crystals (positive bifringence, blue under polarized light when parallel).

Gonococcal arthritis

Purulent synovial fluid (charactaristic of all forms of infective arthritis)

Typically monoarticular (knee, wrist and small joints)

Infective Arthrits

Caused by infection with the spyrochete Borrelia burgdorfi (typically from a lxodes dammini tick)

Charactarized by a skin lesion: Erythema Chronicum Migrans a slowly spreadking lesion with a bull's-eye appearence.

Leads to polyarticular arthritis as ell as cardiac and neurolgic changes.

Hypertrophic osteoarthropathy

Chronic condition that often manifests as clubbinf of the fingers with associated periostitis at the distal end of the radius and ulna.

Can also have painful swelling and tenderness of the peripheral joints.

Rhabdomyosarcoma

A malignant tumor of skeletal muscle

Variants include pleomorphic, embryona, and alveolar rhabdomyosarcomas.

False

Synovial sarcomas are highly malignant soft tissue tumors that typically originate in the tissue adjacent to the joint cavity (rather than in the cavity itself).

Most often occurs in the lower extremities.

Lipoma is the most common soft tissue tumor overall (all age groups, malignant or benign)

It is a benign tumor of mature adipose tissue.

Prognosis is good (as it is with the malignant counterpart: Liposarcoma)