CartilageStrong, flexible type of connective tissue.- Supports and connects body parts (eg, costal cartilage that connects ribs to sternum)- Provides cushioning in joints Layers:Perichondrum: Layer of connective ...
BoneSurface of bone is covered by periosteum.- Outer fibrous layer: Protects bones, provides attachment for tendons and ligaments.- Inner cellular layer: Progenitor stem cells that develop into osteoblasts ...
Bone remodelingContinuous process where bones are resorbed by osteoclasts and remade by osteoblasts. RANKL → initiates remodelingOsteoprotegerin → Turn off remodeling Repairs tiny cracks due to normal activities.Help ...
Fibrous, cartilage, and synovial joints206 bones connected by 360 joints. 1. Fibrous joints (fixed)- Bones are connected by ligaments.- Sutures: Completely fixed in adults; allows molding during childbirth- Syndesmosis: Joing between radius ...
Frakturkallus1. Fraktur mit angrenzend devitalisierter Knochen mit leeren Osteozytenhöhlen 2. Periostaler und intramedullärer Kallus: Regelrecht gebildete, teilweise mineralisierte Knochensubstanz in Form von Arkaden ...
Osteoporose1. Verschmälerte Kortikalis 2. Reduzierte Zahl und Breite der spongiösen Knochenbälkchen 3. Verminderung des Spongiosagerüsts im Zentrum stärker ausgeprägt als in der Peripherie 4. Keine Resorptionslakunen ...
OsteoporosisSkeletal condition in which the loss of bone mineral density leads to decreased bone strength and an increased susceptibility to fractures. Etiology:1. Primary Osteoporosis- Type I (postmenopausal osteoporosis): ...
Paget disease of boneCommon, localized disorder of bone remodeling caused by ↑ osteoclastic activity followed by ↑ osteoblastic activity that forms poor-quality bone.- Leads to deformities and potential fractures.- Second ...
Morbus Paget1. Spongiosabälkchen sind auffallend verdickt, vermehrt und unregelmässig geformt. 2. Prominente Zementlinien sind mosaikartig angeordnet. 3. Riesenosteoklasten mit über 20 Kernen. 4. Lockere Markfibrose. ...
Renale Osteodystrophie1. Stark erhöhter Spongiosaumbau 2. Fibroosteoklasie: Lakunen mit osteoklastäre Knochenresorption mit Begleitfibrose 3. Osteoidose: Osteoblasten- und Osteoidsaum
OsteoarthritisJoint disease characterized by a degeneration of the joint complex (articular cartilage, subchondral bone, and synovium) that occurs with old age or from overuse. Synovium:- Consists of connective tissue, ...
Synovialitis bei chronischer Osteoarthritis1. Synoviale Zottenhyperplasie 2. Verbreiterung der Deckzellschicht 3. Lymphofollikuläre Entzündungsinfiltrate im Stroma. 4. Einschlüsse von Knorpel- und Knochenfragmenten (Detritussynovialitis) 3. ...
Rheumatoid arthritisSystemic inflammatory autoimmune disorder characterized by joint pain, swelling, and synovial destruction. Risk factors: Genetics (HLA-DR1, HLA-DR4) and environmental trigger (smoking, infection) Citrullation ...
Osteoarthrose1. Gelenkknorpel: Zerstörung unterschiedlichen Grades, von oberflächlicher Aufblätterung (Fibrillation) über vertikale Substanzrisse und Zerklüftung bis zur (sub-)totalen Abschleifung. 2. Mikrofrakturen ...
ChondrosarcomaMalignant tumor arising from mesenchymal cells that produce cartilage.- Age: usually > 50 years- M > F Symptoms:- Deep, dull pain (worsens at night, insidious progression over months to years)- Local ...
Chondrosarkom1. Zerstörung der Spongiosa und Kortikalis durch Tumorausläufer 2. Nodule/Läppchen aus hyalinem Knorpel, evlt. periphere Kalzifizierung 3. Leichte bis mässige Zell- und Kernpolymorphie; gelegentlich ...
OsteosarcomaMalignant, osteoid and bone-forming tumor arising from osteoblasts located in the periosteum.- Most common primary bone malignancy - Bimodal distribution→ Primary osteosarcoma: puberty/adolescence→ ...
Osteosarkom1. Malignitätszeichen: Zell- und Kernpolymorphie, atypische Mitosen 2. Bildung von Osteoid (für die Diagnose eines Osteosarkoms ausschlaggebend; nicht anwesend beim Chondrosarkom)
Ewing sarcomaMalignant bone tumor arising from neuroectodermal cells.- Associated with translocation t(11;22) (fusion protein EWS-FLI1) - Most common in Caucasians- Generally boys < 15 years old Symptoms:- Localized ...
Ewing-Sarkom1. Blauer, klein- und rundzelliger Tumor 2. Uniforme Zellen mit schmalem, kaum abgrenzbarem Zytoplasmasaum und unscharfen Zellgrenzen 3. Lobuläre Architektur: Durch Bindegewebssepten abgegrenzte Knoten ...
Giant-cell tumor of bone (osteoclastoma)Locally aggressive tumor composed of giant cells that arise from the bone marrow. Peak incidence: 20-40 years Localization: Epiphyseal/metaphyseal region of the long bones (predominantly bones close to ...
Riesenzelltumor1. Mehrkernige Riesenzellen 2. Mittelgrosse, polygonale bis plump spindelige, einkernige Zellen 3. Nebst fokaler Kollagenisierung (Vernarbung, oft mit Hämosiderin) keine Matrixbildung, d.h. keine Knochen- ...
Muskelfaser-TypenTyp 1:- rot- langsam- ständige Aktivierung- viele oxidative Enzyme- Aerob (Oxidation)- viele Mitochondrien- viel Speicherfett- ATPase pH 9.4 hell Typ 2:- weiss- schnell- plötzliche Aktivierung- wenige ...
Inclusion-body myositis (IBM)Inflammatory myopathy that progresses slowly over years. Symptoms:- Selective and asymmetric muscle involvement of both proximal and distal muscle groups- Quadriceps muscle weakness: knees lack support ...
AchondroplasiaEtiology:- Activating mutation in fibroblast growth factor receptor 3 gene (FGFR3) → inhibited chondrocyte proliferation → reduced endochondral ossification- New mutations in ∼80% of cases; autosomal ...
Osteogenesis imperfecta (“brittle bone disease”) ...Etiology: Autosomal dominant mutation in COL1A1 or COL1A2 genes; decreased formation of hydrogen and disulfide bonds between type 1 preprocollagen molecules → decreased triple helix formation → defective ...
OsteomalaciaBone softening caused by impaired mineralization. Pathophysiology: Vitamin D deficiency and defective vitamin D metabolism- Hypocalcemia → defective bone matrix mineralization - Renal disease → ...
RicketsBone softening caused by impaired mineralization. Pathophysiology: Vitamin D deficiency and defective vitamin D metabolism- Hypocalcemia → defective growth plate mineralization- Renal disease → ...
OsteopetrosisInherited, diffuse bone disease that results in increased sclerotic appearance of the skeleton on radiological examination (from Latin: "petrosus" = stony). Etiology:- Type I osteopetrosis (malignant ...
OsteomyelitisOsteitis: general term for inflammation of the boneOsteomyelitis: infection of the bone marrow Etiology:- Hematogenous osteomyelitis- Exogenous osteomyelitis: usually due to multiple pathogens→ Posttraumatic: ...
Benign bone tumorsOsteochondroma- Most common benign bone tumor.- Males < 25 years old.- Metaphysis of long bones.- Lateral bony projection of growth plate (continuous with marrow space) covered by cartilaginous cap. ...
Malignant bone tumorsOsteosarcoma- Accounts for 20% of 1° bone cancers.- Peak incidence of 1° tumor in males < 20 years.- Less common in elderly- Usually 2° to predisposing factors, such as Paget disease of bone, bone ...
Bone metastasesBone metastasis >> 1° bone tumors (eg, multiple myeloma, lytic). - Breast (mixed)- Prostate (blastic)- Lung (lytic)- Thyroid (lytic)- Kidney (lytic) Predilection for axial skeleton.