Phase 1 - Week 5 (Bones, Cartilage, Osteoarthritis), Phase 2 - Week 4 + 6 (Synovial Joints, Rheumatoid Arthritis, Wrist + Hand, Hip + Knee, Fractures) Flashcards
(219 cards)
1
Q
Where is the diaphysis of a long bone?
A
The central shaft
2
Q
Where is the epiphysis of a long bone?
A
The regions at either end of the bone
3
Q
Epiphyseal plate of a long bone
A
Present in growing bones, between the diaphysis and epiphyses. Also called growth plate. Growth in length of the bone is the result of deposition of new cartilage at the epiphyseal plate and subsequent mineralisation.
4
Q
Where is the metaphysis of a long bone?
A
Adjacent to the epiphyseal plate, at the growing end of the diaphysis
5
Q
What is the epiphyseal line?
A
After puberty the epiphyseal plate becomes fully calcified and remains as the epiphyseal line
6
Q
Periosteum
A
Covers the surface of bones, consists of an outer layer of tough fibrous connective tissue and an inner layer of osteogenic tissue
7
Q
Medullary cavity
A
Space running through the centre of bone, lined with osteogenic tissue (endosteum). Contains fatty yellow marrow - not involved in haematopoiesis
8
Q
Where is red bone marrow located and what is its function?
A
Found in small, flat and irregular bones and the epiphysis of long bones. Contains haematopoietic tissue which produces blood cells
9
Q
Describe the blood supply to long bones
A
- Nutrient artery - splits into ascending/descending medullary artery
- Periosteal arteries - outside of bone
- Metaphyseal arteries + epiphyseal arteries supplied by the nutrient artery
10
Q
List the types of bone tissue
A
- Compact (dense/cortical)
2. Spongey (trabecular/cancellous)
11
Q
Where is cortical bone located?
A
- Outer region of all bones
- Diaphysis of long bones
- Outer and inner regions of flat bones
12
Q
What is the function of cortical bone?
A
Few spaces, provides protection + support especially to long bones - reduce the stress of weight bearing
13
Q
What are the functional units of cortical bone?
A
Osteons
14
Q
Describe the structure of osteons
A
- Central canal containing blood vessels, lymphatics + nerves
- Surrounded by rings of intercellular substance (lamellae) with spaces (lacunae) between containing osteocytes (mature bone cells)
- Tiny canals (canaliculi) radiate from lacunae forming a branching network by which nutrients/waste products are transported to and from the osteocytes
15
Q
Describe the structure of trabecular bone
A
- Irregular lattice of thin plates of bone called trabeculae between which there are large spaces filled with bone marrow
- Lacunae containing osteocytes within the trabeculae
- Osteocytes are nourished directly by blood circulation through marrow cavities from blood vessels penetrating spongey bone from the periosteum
16
Q
Where is trabecular bone located?
A
Epiphysis of long bones, most of short, flat and irregular bones
17
Q
List the types of bone cells
A
- Osteoblasts
- Osteocytes
- Osteoclasts
18
Q
Give the progenitor cells for osteoblasts, osteocytes and osteoclasts
A
Osteoblasts - osteoprogenitor cells
Osteocytes - osteoblasts
Osteoclasts - mononuclear phagocytic cells
19
Q
Where are osteoblasts found?
A
Surface of all bones, line the internal marrow cavities
20
Q
How is the structure of osteoblasts specialised for their function?
A
Contain numerous mitochondria and golgi apparatus for rapid protein synthesis
21
Q
What is the function of osteoblasts?
A
Secrete the constituents of osteoid - the organic matrix of the bone - collagen, proteoglycans + glycoproteins. Important in the process of mineralisation of the matrix
22
Q
Which hormones regulate the activity of osteoblasts
A
Parathyroid hormone and calcitriol
23
Q
Where are osteocytes located?
A
Trapped in lacunae within the matrix
24
Q
Describe the function of osteoclasts
A
- Giant multinucleated cells
- Highly mobile
- Responsible for resorption of bone during growth and skeletal remodelling
- Bone resorption through the action of collagenase, lysosomal enzymes and acid phosphatase
25
Where are osteoclasts located?
Abundant at surfaces of bone undergoing erosion. At site of contact with bone, highly folded 'ruffled border' of microvilli that infiltrates the disintegrating bone surface.
26
What are the products of bone dissolution and where are they released?
Calcium, phosphate and bone matrix constituents are released into the extracellular fluid
27
Which hormones control the activity of osteoclasts?
Parathyroid hormone, calcitonin, thyroxine, oestrogen + metabolites of vitamin D
28
Describe the main functions of bone
1. Protection and structural support
2. Attachment for muscles, tendons + ligaments allowing movement by means of articulation (joints)
3. Homeostasis of minerals (calcium + phosphate)
4. Forming blood cells - haematopoietic tissue in red bone marrow in short, flat and irregular bones
29
Where does the nutrient artery enter the bone?
Nutrient foramen
30
Volkmann's canals
Transfer blood from periosteum to central canals of osteons
31
List the types of joints by structural classification
1. Fibrous joints
2. Cartilaginous joints
3. Synovial joints
32
Describe the structure of fibrous joints
- Predominantly synarthroses
- Held together by fibrous connective tissue
- No space between bones - immovable
33
List the types of fibrous joints
1. Sutures
2. Syndesmoses
3. Gomphoses
34
Suture joints
- In skull
| - Short fibres of connective tissue hold bones tightly in place
35
Syndesmosis joints
- Bones connected by band of connective tissue
- Small amount of movement depending on length of fibres
- E.g. joint of tibia and fibula in ankle
36
Gomphosis joints
- Between teeth and sockets
| - Connected into socket by connective tissue called periodontal ligament
37
Describe the structure of cartilaginous joints
- Predominantly amphiarthroses
- Bones connected by cartilage
- Slight movement
38
List the types of cartilaginous joints
1. Synchondroses
| 2. Symphyses
39
Synchondrosis joints
- Bones joined by hyaline cartilage
| - In epiphyseal plates of growing children
40
Symphysis joints
- Hyaline cartilage covers end of bone but connection between bones is fibrocartilage
- Joints between vertebrae, pubic symphysis
41
Describe the structure of synovial joints
- Predominantly diarthroses
- Have space between bones - synovial cavity, filled with synovial fluid
- Synovial fluid lubricates joints, reduces friction between the bones and allows greater movement
- Ends of bones covered with articular cartilage (hyaline cartilage)
42
List the types of movement possible at synovial joints
1. Gliding (flat bone surfaces) e.g. carpal and tarsal
2. Angular - flexion, extension, abduction, adduction, circumduction
3. Rotational - medial or lateral
4. Special - inversion, eversion, protraction, retraction, elevation, depression etc.
43
Describe the structure of the articular capsule of synovial joints
- Articular capsule is fibrous and continuous with periosteum of articulating bones
- Articular capsule consists of two layers - outer fibrous membrane, may contain ligaments and inner synovial membrane that secretes the synovial fluid
44
What is the function of synovial fluid?
Lubricating, shock-absorbing, joint nourishing
45
List the components of synovial fluid
- Blood monocytes
- Hyaluronic acid
- Lubricin
- Proteinases
- Collagenases
46
What is the synovial membrane?
Soft tissue between articular capsule and joint cavity of synovial joints
47
Describe the structure of the synovial membrane
2 layers
1. Outer layer or subintima - fibrous, fatty or loosely areolar
2. Inner layer or intime - thin sheet of cells
48
How are synovial joints stabilised?
Ligaments around the joint allow less movement making the joint stronger and less susceptible to injury
49
List the types of synovial joint
1. Pivot - between C1/C2 vertebrae
2. Hinge joint - elbow
3. Saddle joint - trapezium carpal bone-1st metacarpal bone
4. Plane joint - between tarsal bones
5. Ball + socket - hip joint
6. Codyloid joint - radius-carpal bones of wrist
50
List the structural classifications of types of cartilage
1. Hyaline cartilage
2. Fibrocartilage
3. Elastic cartilage
51
Describe the production of cartilage
- Mesenchymal cells differentiate into chondroblasts which produce cartilage
- Chondroblasts grow and begin synthesis of proteoglycan ground substance and fibrous extracellular matrix
- Chondroblasts develop into chondrocytes (mature cartilage cells)
52
Perichondrium
- A layer surrounding mature cartilage masses
- Composed of collagen fibres and spindle shaped cells resembling fibroblasts
- Also contains capillaries from which nutrients diffuse into the cartilage matrix
53
Which types of cartilage have/do not have a perichondrium
Hyaline and elastic cartilage has a perichondrium, articular hyaline and fibrocartilage do not have a perichonidrium
54
What is consequence of cartilage not possessing a perichondrium?
Cannot regenerate after damage - poor blood supply
55
How are metabolites transferred between chondrocytes and the surrounding tissues?
- Through diffusion through the water of the ground substance
- This limits the thickness of cartilage - thick areas need cartilage canals to allow small vessels into centre of cartilage of cartilage mass
56
Where is hyaline cartilage found?
- On articular surfaces of joints - over surface of bone ends
- Nasal septum
- Tracheal rings
- Sternal ends of ribs
57
Describe the macrostructure of hyaline cartilage
Characterised by small aggregates of chondrocytes embedded in amorphous matrix of ground substance, reinforced by collagen fibres
58
Where is fibrocartilage found?
In intervertebral discs, pubic symphysis, ligaments, connections of tendons to bones
59
Describe the macrostructure of fibrocartilage
- Resembles dense connective tissue, very abundant collagen fibres with intervening bands of ECM
- Alternating layers of hyaline cartilage matrix with thick layers of dense collagen fibres, orientated in direction of the functional stress
60
Where is elastic cartilage found?
External ear, larynx, epiglottis, walls of Eustachian tubes
61
Describe the macrostructure of elastic cartilage
- Firm but flexible due to elastin fibres within ECM similar to hyaline cartilage
- Elasticity from bundles of branching elastin fibres in cartilage matrix
62
Describe the microstructure of hyaline cartilage
Matrix of chondroitin sulphate into which many fine collagen fibrils are embedded, contains numerous chondrocytes
63
Explain the function of hyaline cartilage
- Provides smooth surfaces enabling movement/sliding of tissues over each other e.g. at joints
- Provides flexibility and support
64
Describe the microstructure of fibrocartilage
- Tough cartilage - chondrocytes scattered among visible dense bundles of collagen fibres within the matrix
65
Explain the function of fibrocartilage
- Provides support and rigidity to attached/surrounding structures
- Strongest type of cartilage
66
Describe the microstructure of elastic cartilage
Chondrocytes located in a threadlike network of elastic fibres within the matrix
67
Explain the function of elastic cartilage
Provides support to surrounding structures, helps define + maintain the shape of the area, e.g. external ear
68
Define osteoarthritis
Progressive disorder of the joints caused by gradual loss of cartilage and resulting in the development of bony spurs and cysts at the margins of the joints
69
Describe the features of an osteoarthritic joint
- Thickened capsule - synovial hypertrophy
- Cyst formation and sclerosis
- 'Shelving' - fibrillated cartilage
- Osteophytic lipping
- Altered contour of bone
- Cartilage erosion down to subchondral bone
70
Describe the pathogenesis of osteoarthritis
- Decrease in water content
- Decrease in proteoglycan synthesis
- Increase in collagen x-linking
- Traumatic damage
71
Which joints are most commonly affected by osteoarthritis?
Weight bearing joints e.g. knees/hips and hands
72
List and describe the types of osteoarthritis
1. Primary - degenerative disorder
| 2. Secondary - due to trauma, hip dysplasia, infection or diabetes
73
List the risk factors associated with development of osteoarthritis
- Age - <45
- Genetics
- Gender - <50 men at higher risk, >50 women at higher risk
- Nutritional - low Vitamin C/D intake
- Joint trauma
- Obesity
- Occupation
- Abnormal joint biomechanics e.g. hip dysplasia
- Knee extensor weakness
- Sports w/ joint risk
74
List the symptoms associated with osteoarthritis
- Pain, especially when doing load-bearing activities e.g. walking
- Short lived stiffness in the morning - improves in 30 mins or less
- Difficulty moving affected joints
- Swelling
75
Describe the features found when taking a clinical history which would indicate osteoarthritis
- Pain
- Decreased walking distance
- Sleep disturbance
- Limp - Trendelenburg sign
- Stiffness
76
Describe the typical features seen on X-Rays of osteoarthritic joints which are used in diagnosis of the disease
- Joint space narrowing
- Osteophytes - ossifying cartilaginous protrusions lead to irregular outgrowth of new bone
- Fragmentation of osteophytesor articular cartilage results in presence of intra-articular loss bodies (joint mice)
- Subchondral sclerosis
- Cyst formation
77
Explain the general aims of management of osteoarthritis
- Symptoms of osteoarthritis progress slowly over many years
- There is no cure for osteoarthritis
- Treatment is directed at symptom management/slowing progress of condition
- Goals include reducing pain, increasing range of motion and increasing muscle strength
78
List the non-operative treatments used to manage osteoarthritis
1. Medications
2. Physiotherapy
3. Walking aids
4. Joint injections
79
Describe how medication can be used to manage osteoarthritis
- Pain management - paracetamol, NSAIDs
| - Alternative medication - glucosamine/chondroitin sulfate
80
Describe how physiotherapy can be used to manage osteoarthritis
- Exercises to improve range of motion
- Muscle strengthening
- Aerobic condition
- Weight loss
81
Describe how walking aids can be used to manage osteoarthritis
- Particularly used for osteoarthritic hips
- Transfer load to unaffected side
- Reduces load on hip by 40%
82
Describe how joint injections can be used to manage osteoarthritis
- Cortisone/corticosteroid
- Reduce inflammation response around joint
- More rapid effect than NSAIDS
- Viscous supplement - replace midified synovial fluid in joints
- Increase viscosity + elasticity of fluid
83
List the surgical treatments used to manage osteoarthritis
1. Arthroscopy
2. Cartilage transplantation
3. Joint transplantation
84
Describe how arthroscopy is used to manage osteoarthritis
- Keyhole
| - Debridement of articular cartilage
85
Describe how cartilage/joint transplantation is used to manage osteoarthritis
- Remove worn cartilage and replace with cartilage from other joints/synthetic material
- Remove whole of joint + replace with synthetic material
- Pain relief and increase in range of motion
- Improve activities of daily living
86
What is the extracellular matrix (ECM)
- The acellular component of supporting/connective tissue
- Complex network of proteins and ploysaccharides
- Secreted locally by cells and remain closely associated with them
- Provides structural, adhesive and biochemical signalling support
87
Where is ECM found?
- Bone
- Tendon
- Cartilage
- BV walls
- Subcutaneous fat
- Vitreous body of the eye
- Cornea
- Dermal layer of skin
- Basement membrane
88
Describe the components of the ECM
1. Fibres - collagen + elastin
| 2. Ground substance - proteoglycans, glycosaminoglycans (e.g. hyaluronan), glycoproteins
89
List some morphologically and functionally distinct ECM types
1. Submucosa - loose networks to allow movement
2. Skin - tightly 'woven' 3D gives resilient properties
3. Tendon - unidirectionally aligned for tensile strength
4. Bone - calcified for mechanical strength
5. Basal lamina - ultrathin tough sheets for separation/filtration
90
Describe the function of ECM
- Mechanical and structural support
- Tensile strength
- Determines cellular microenvironment
91
Describe how ECM determines the cellular microenvironment
- Anchors cells
- Strongly influences embryonic development
- Provides pathways for cellular migration (e.g. wound repair)
- Sequesters growth factors
- Provides a residence for roaming phagocytic cells
- Establishes and maintains stem cell niches
92
Explain collagen's role in ECM
- Major insoluble fibrous protein of ECM
- Fibrillar collagen in skin, tendons, bones for strength
- Sheet/network-forming in basement membrane for support/filtration
93
List the types of collagen and where they are found
1. Type I - dermis, tendons, ligaments, bones
2. Type II - hyaline cartilage
3. Type III - liver, bone marrow, lymphoid organs, granulation tissue
4. Type IV - basement membranes
5. Type V - linker to basement membrane, cornea
94
Explain the role of elastin in ECM
- Structural protein arranged as fibres
- In skin, lungs + BVs - stretch and elastic recoil
- Assembly into functional fibres requires the presence of a structural glycoprotein - Fibrillin
95
Ground substance
- Amorphous, colourless, gelatinous material
- Fills the spaces between fibres and cells
- Consists of large molecules - glycosaminoglycans (GAGs) which link together to form proteoglycans
- V good at absorbing water so resistant to compressive forces
96
Glycosaminoglycans
- Also called mucopolysaccharides
- Chains of repeating disaccharide units
- Carbohydrate component of proteoglycans
- E.g. hyaluronic acid in synovial fluid
- Attracts water - gel/cushioning + hydrating properties
97
List some proteoglycans of ECM and where they are found
- Aggrecan - cartilage
- Perlecan - basement membrane
- Syndecan - cartilage
- Decorin - widespread in connective tissues
98
List some glycoproteins and their functions
- Fibrillin - controls deposition and orientation of elastin
- Fibronectin - linker role in BM
- Laminin - primary organiser of BM
- Entactin - linker role in BM
- Tenascin - linker role in connective tissue
99
Describe the synthesis of collagen
- Synthesised as pro-collagen
- Undergoes post-translational modifications - glycosylation + hydroxylation
- Assembled into a triple helix
100
Describe the synthesis of elastin
- Synthesised as tropoelastin
- Undergoes post-translational modification - hydroxylation
- Assembled as a fibrillin scaffold with cross-linked fibres
101
Describe the synthesis of proteoglycans
- Core protein synthesises on rER
- Addition of polysaccharide as disaccharide repeats in Golgi
- Delivered to extracellular compartment by exocytosis
- Assembly with other ECM components
102
Describe the steps involved in ECM remodelling
1. Degradation
2. Deposition
3. Modification
103
List the proteins involved in ECM remodelling and describe the changes they bring about
Proteases, matrix-metalloproteinases (MMPs) and elastase
Involved in wound repair, embryogenesis and angiogenesis
104
Describe the structure of the basement membrane/basal lamina
- Thin, tough sheet of ECM
| - 3 layers - lamina lucida, lumina densa, lamina fibroreticularis
105
List the components of the basement membrane/basal lamina
- Collagen IV
- Laminin (glycoprotein)
- Perlecan (heparan sulphate proteoglycan)
- Entactin + fibronectin (glycoprotein)
106
List the functions of the basement membrane
- Support
- Binding to underlying connective tissue
- Mediates signals between cells and connective tissue
- Determines cell polarity
- Permits flow of nutrients (permeability)
- Path for cell migration
- Barrier to downward growth
107
List some disorders of the basement membrane
1. Cancer - epithelial tumours regarded as malignant once BM is breached
2. Diabetes mellitus - thickening of BM in glomerulus changes permeability
3. Epidermolysis bullosa - attachment of epidermis to BM
4. Goodpastures syndrome - autoantibodies to collagen IV destroy BM in glomerulus and lung
108
What is the main mineral component of osteoid?
Calcium hydroxyapatite
109
What type of collagen is found in cartilage?
Type II
110
What is the effect of dysfunction of elastin in ECM?
Supravalvular aortic stenosis (SVAS) - arterial defects
111
What is the effect of dysfunction of Fibrillin-1 in ECM?
Marfan syndrome - skeletal, ocular + cardiovascular abnormalities
112
What is the effect of dysfunction of collagen in ECM?
Ehlers-Danlos syndrome - joint + skin abnormalities
113
What is the effect of dysfunction of keratan sulphate in ECM?
Macular corneal dystrophy - corneal transparency
114
What is the effect of dysfunction of perlecan in ECM?
Silverman-Handmaker type of dyssegmental dysplasia (DDSH) - neonatal lethal dwarfism
115
List the articulations of the hip bones
1. Sacroiliac joint - articulation with the sacrum
2. Pubis symphysis - articulation between left and right pelvis
3. Hip joint - articulation with the head of the femur
116
List the parts of the hip bone
1. Ilium
2. Ischium
3. Pubis
117
Describe the hip joint articulation
Cup-shaped socket called the acetabulum articulates with the head of the femur. Ball + socket joint.
118
Describe the structure of the ilium
- Located superiorly
- Expands superiorly to form wing (ala)
- 2 surfaces of the wing - internal and external
- Internal = concave, produces iliac fossa - site of origin of iliacus muscle
- External = convex, attachment of gluteal muscles
- Superior margin = iliac crest - from anterior superior iliac spine to posterior superior iliac spine
- Posterior aspect has greater sciatic notch
119
Describe the structure of the pubis bone
- Anterior portion of hip bone
- Made of body, superior ramus and inferior ramus
- Pubic body = medial, articulates w/ opposite pubic body at pubic symphysis
- Superior pubic ramus = extends laterally from body to form part of acetabulum
- Inferior pubic ramus - projects towards ischium
- Obturator foramen = through which obturator nerve, artery and vein pass through to reach lower limb
120
Describe the structure of the ischium
- Posteroinferior
- Made of body, inferior ramus and superior ramus
- Inferior ischial ramus + inferior pubis ramus forms ischiopubic ramus which encloses part of obturator foramen
- Posteroinferior aspect forms ischial tuberosity
- Ischial spine = near junction of the superior ramus and body is posteromedial projection of bone
121
Explain which important ligaments attach to the ischium
1. Sacrospinous ligament - runs from ischial spine to sacrum, creating the greater sciatic foramen through which lower limb neurovasculature (including sciatic nerve) transcends
2. Sacrotuberous ligament - runs from sacrum ischial tuberosity, forming the lesser sciatic foramen
122
Describe the function of the hip joint
- Designed for stability + weight bearing
| - Smaller range of movement than shoulder - more stable
123
Describe the structure of the acetabulum
- Deepened by fibrocartilaginous collar - acetabular labrum
124
Describe the intracapsular ligaments which stabilise the hip joint
Ligament of head of femur (from acetabular fossa to fovea of femur). Encloses a branch of the obturator artery (artery to head of femur), a minor source of arterial supply to the hip joint.
125
Describe the extracapsular ligaments which stabilise the hip joint
1. Iliofemoral ligament - prevents hyperextension
2. Pubofemoral ligament - prevents excessive abduction and extension
3. Ischiofemoral - prevents excessive extension
126
Describe the vascular supply to the hip joint
- Arterial supply from medial and lateral circumflex femoral arteries - branches of profunda femoris artery
- They anastomose at base of femoral neck to form a ring - small arteries arise from ring to supply hip
- Medial circumflex artery - majority of arterial supply
127
Explain the effect of damage to the medial circumflex femoral artery
Can cause avascular necrosis of femoral head
128
List the additional arterial supply to the head of the femur
- Artery to head of femur
| - Superior/inferior gluteal arteries
129
Describe the innervation of the hip joint
- Femoral nerve
- Obturator nerve
- Superior gluteal nerve
- Nerve to quadratus femoris
130
List the movements of the hip joint
1. Flexion
2. Extension
3. Abduction
4. Adduction
5. Lateral rotation
6. Medial rotation
131
How is flexion at the hip joint increased?
When knee is flexed - relaxes the hamstring muscles
132
How is extension at the hip joint limited?
Joint capsule and iliofemoral ligament
133
Describe the structure of the head of the femur
Smooth surface w/ a depression on the medial aspect, for the attachment of the ligament of the head of the femur
134
List the significant structural parts of the proximal femur
- Head
- Neck
- Greater trochanter
- Lesser trochanter
- Lesser trochanteric line
- Intertrochanteric crest
135
Describe the structure of the neck of the femur
- Connects head of femur to shaft
- Cylindrical, projecting in superior + medial direction - angle of projection allows for increased range of movement at hip joint
136
Greater trochanter of the femur
- Projection of bone
- Originates from anterior aspect, lateral to neck
- Angled superiorly + posteriorly
- Site of attachment for many muscles in gluteal region, e.g. gluteus medius, gluteus minimus and piriformis
137
Lesser trochanter of the femur
A tuberosity from the medial aspect of the neck of the femur
138
Intertrochanteric line
Thin, roughed line that joins the trochanters anteriorly
139
Intertrochanteric crest
Thick, rounded ridge that joins trochanters posteriorly
140
List the articulations of the knee joint
1. Femoropatellar joint - between patella and from of femur
| 2. Femorotibial joint - between femur and tibia
141
List the bones involved in the knee joint
1. Femur - lateral + medial condyle
2. Tibia - lateral + medial condyle
3. Patella - articular facets
142
Describe the types of movement possible at the knee joint
- Flexion
- Extension
- Medial rotation
- Lateral rotation
143
Describe the synovial membrane and joint capsule of the knee joint
- Joint is lined by synovial membrane from upper border of the patella, between the femur and the quadriceps tendon to form the suprapatella bursa
- The capsule and synovial membrane surround the entire joint to create a single synovial cavity
144
List the intracapsular ligaments which stabilise the knee joint
1. Anterior cruciate ligament
| 2. Posterior cruciate ligament
145
List the extracapsular ligaments which stabilise the knee joint
1. Tibial collateral
| 2. Fibular collateral
146
Describe the epidemiology of hip fractures
- Typically occur in elderly female patients
- Also common in high impact trauma
- Mean age = 75 y/o
- 20-35% mortality in first year
147
List the types of hip fracture
1. Extracapsular
| 2. Intracapsular
148
Extracapsular hip fractures
- Fracture occurs outside joint capsule
- Blood supply to femoral head not affected
- Complications of bone union are rare
- Described as stable or unstable
- Unstable = detached fragment of lesser trochanter
149
Intracapsular hip fractures
- Fracture occurs inside joint capsule
- Can affect blood supply to femoral head, especially if fracture is displaced (ends of bone are not aligned)
- Complications common - avascular necrosis of femoral head
150
Describe the typical clinical presentation of hip fractures
- History of fall/trauma
- Leg may be shortened/externally rotated in displaced trauma
- 10% have other fracture
- Avascular necrosis is common - treated with total hip replacement
- Sciatic nerve damage risk in dislocation fractures + dislocation
151
Describe the treatment of undisplaced intracapsular hip fractures
Can often displace without treatment so are treated with internal fixation using a dynamic hip screw. 5% have avascular necrosis - will need hip replacement
152
Describe the treatment of displaced intracapsular hip fractures
Reduction and fixation - high risk of non-union and fixation failure. 15% have avascular necrosis. Hemiarthroscopy often first line - femoral head is replaced but not acetabular cup. Total hip replacement often only for osteoarthritis. Reduction and fixation more likely in younger patients (without underlying pathology)
153
Describe treatment of extracapsular hip fractures
Internal fixation
154
Describe methods of fall prevention in the home
- Removing wires and frayed carpets
- Using non-slip mats/rugs
- Wearing well fitting shoes that support the ankle
- Railing around home
- Bars in bathroom
- Personal alarm system
155
List other methods of fall prevention for the elderly
1. Strength and balance training e.g. Tai Chi
2. Medication review - some medications' side effects may increase risks of fall
3. Sight tests - poor vision increases chance of falls
4. Avoiding alcohol/reducing consumption
156
List the components of a synovial joint
1. Articular cartilage
2. Synovial cavity
3. Articular capsule
4. Synovial fluid
5. Accessory ligaments
6. Articular fat pad
7. Bursae and tendon sheaths
157
Synovial cavity
- Space between two articulating bones
| - Contains a small amount of synovial fluid
158
Articular capsule
- Surrounds any surface within interior joint not covered by hyaline cartilage
- Two layers - external fibrous membrane and internal synovial membrane
159
Accessory ligaments of synovial joints
- Intracapsular and extracapsular
- Stabilise the joint
- Intracapulsar - within articular capsule, outside synovial cavity, e.g. cruciate ligaments
- Extracapsular - outside joint capsule, e.g. tibial collateral ligament
160
Articular fat pads
- Accumulation of adipose tissue
- Between fibrous capsule and synovial membrane
- Found in most synovial joints
- E.g. infrapatellar fat pad of knee
- Some also have cartilaginous disc between bones for additional cushioning
161
Bursae
- Found in close proximity to synovial joints
- Fibrous, slightly flattened sacs, lined with synovial membrane, containing a thin film of synovial fluid
- Between bone and other tissues e.g. skin, tendons, muscles + ligaments
- Function to cushion movement between structures as they rub together
162
Tendon sheaths
- Reduce joint friction
- Elongated bursae that wrap around tendons subjected to stress
- Found primarily at joints undertaking a high degree of movement
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Define rheumatoid arthritis
A chronic inflammatory autoimmune disease causing pain, swelling and stiffness in the joints
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Which joints are most commonly affected by rheumatoid arthritis
Small joints of the hands, feet and wrists
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Define autoimmunity
Loss of immunological tolerance to self
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What are the causes of autoimmunity?
- Dysfunction in tolerance
- Presentation of self
- Molecular mimicry
- Loss of regulatory mechanisms
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Describe the impact and long-term consequences of rheumatoid arthritis
Can be a major cause of work loss, decreased quality of life and ultimately mortality
168
List the pathways which dysfunction to cause rheumatoid arthritis
T-cell/B-cell/Cytokine signalling pathway abnormalities
169
List the risk factors associated with rheumatoid arthritis
1. Genetic predisposition
2. Environmental factors - e.g. smoking, infection
3. Imbalance of intestinal microbes - natural or as a result of an infection or other event
4. Sex - females at higher risk
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Explain how genetic predisposition can increase risk of rheumatoid arthritis
- Gene associated with RA = HLA-DR4, found in 60-70% of caucasians wth RA, 20% of general population
- Increases liklihood of develoing RA - not an accurate diagnostic tool
171
Explain how environmental factors can increase risk of rheumatoid arthritis
- Smoking and nicotine exposure - not fully understood, believed that prolonged smoking increases rheumatoid factor (antibody, presence of which in the blood is a sign of autoimmunity)
- Diet - regularly drinking sugary drinks increases risk. People who are overweight or obese have a greater risk of developing rheumatoid arthritis, symptoms are worse
172
Explain how sex can increase risk of rheumatoid arthritis
- Disruption in hormone balance
- Women more likely to have RA than men, suggests hormones are a factor
- Possibly due to oral contraceptives - containing progesterone/oestrogen
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List the diagnostic tools used to diagnose rheumatoid arthritis
1. Symptoms/clinical examination
2. Blood tests
3. Imaging tests
174
Describe the symptoms which indicate rheumatoid arthritis
Active synovitis lasting 6+ weeks:
- Inflammation of joint's synovial tissue
- Symptoms = swelling, redness, warmth, pain + stiffness
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Describe how blood tests can be used to diagnose rheumatoid arthritis
Test for rheumatoid factor (RF), anti-cyclic citrullinated peptide (anti-CCP) and inflammatory markers such as erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP)
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List the imaging techniques used to diagnose rheumatoid arthritis
- Can show evidence of joint damage/inflammation
- Ultrasound
- X-Ray
- MRI
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Explain how ultrasound can be used to diagnose rheumatoid arthritis
- Detect inflammation of synovial tissue that encapsulates joints + tendons - synovitis
- Can also detect tenosynovitis in finger, early sign of RA
- Can be used to measure patient's response to drugs
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What is the goal of treatment of rheumatoid arthritis
No cure - management to allow high quality of life
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List the methods used to treat rheumatoid arthritis
1. Physiotherapy
2. Occupational therapy
3. Psychological interventions
4. Pharmacological treatment
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Describe the role of physiotherapy in treating rheumatoid arthritis
- Improve general fitness and encourage exercise
- Learn exercises for enhancing joint flexibility, muscle strength and managing other functional impairments
- Short-term pain relief provided by methods such as transcutaneous electrical nerve stimulators (TENS) and wax baths
181
Describe the role of occupational therapy in treating rheumatoid arthritis
- Help with difficulties with any everyday activities
| - Help with problems with hand function
182
Describe the psychological interventions used as part of treatment of rheumatoid arthritis
Relaxation, stress management + cognitive coping skills to help people with RA adjust to living with their condition
183
List the types of pharmacological management used in the treatment of rheumatoid arthritis
1. DMARDs
| 2. Glucocorticoids
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DMARDs
- Disease modifying anti-rheumatic drugs
- Reduce pain, swelling and stiffness over a period of weeks/months by slowing down the disease and its effects on the joints
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Compare DMARDs to NSAIDs and steroids
DMARDs treat the disease, in contrasts to NSAIDs - which treat inflammation but not the underlying cause -and steroids - which blunt the immune response but are insufficient to slow down the progression of the disease
186
List the types of DMARDs
1. Conventional DMARDs
| 2. Biological therapies
187
Describe the mechanism of action of conventional DMARDs
- Slow-acting, can take several weeks to work
- Mechanism of action e.g. Methotrexate = inhibition of T-Cell activation + inhibition of IL-1 binding, selective down-regulation of B cells
188
List some examples of conventional DMARDs
Ciclosporin, cyclophosphamide, hydroxycholoquine, methotrexate
189
Give an example of a biological therapy used to treat rheumatoid arthritis and describe its mechanism of action
- Work more quickly that conventional DMARDs
- E.g. anti-TNF drugs - target proteins called tumour necrosis factor which increases inflammation when excess amounts are present in the blood/joints e.g. infliximab, monoclonal antibodies
- Only given to those who have already had other treatments and not responded well
- Often given in combination with conventional DMARDs
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Describe the use of glucocorticoids to treat rheumatoid arthritis
- Bind to the glucocorticoid receptor - reduces inflammation
- Up-regulate the expression of anti-inflammatory proteins, down-regulate the expression of proinflammatory proteins
- Also play role in development and homeostasis of T lymphocytes
- Lots of adverse side effects - immunodeficiency, withdrawal problems
191
Describe the generic processes of musculoskeletal ageing
- Decreasing amount of tissue
- Altered molecular disposition of the matrix
- Accumulation of degraded molecules
- Reduced efficiency of functional tissue elements
- Reduced synthetic capacity of differentiated cells
- Altered levels of trophic hormones, GFs and cytokines or altered ability of cells to respond
- Alterations in loading patterns of tissues or tissues response to loading
192
Describe the effect of ageing on bone
Reduced bone tissue, relative decline in trophic factors favouring osteoclastic over osteoblasts activity, diminished differentiation potential of bone marrow stem cells
193
Describe the effect of ageing on chondroid tissues
Reduced ability to form large hydrophilic complexes leading to decreased swelling pressure, predisposing to OA and IVD degeneration
194
Describe the effect of ageing on ligaments
Altered collagen synthesis leading to reduced elasticity
195
Describe the effect of ageing on skeletal muscle
Loss of muscle mass and decreased power due to loss of fibre number and fibre atrophy
196
Primary immunodeficiency
Congenital, resulting from genetic defects. Inherited. Deficiency causes disease.
197
Secondary immunodeficiency
Acquired - result of other diseases or conditions.
198
List the immune cells involved with primary immunodeficiencies
- Humoral defect (B cells and antibodies)
- Combines humoral and cellular immunodeficiencies (B and T cells)
- Defect of cell-mediated immunity (T cells)
- Phagocytic dysfunction (PMNs)
- Complement deficiency
199
How do humoral defects present?
- Recurrent sepsis an bacterial infections often in airways
- Chronic gastroenteritis
- Autoimmune disease = arthritis, lupus
- Hyper IgM syndrome, IgA deficiency
200
Describe treatments of primary deficiencies
- Mild - no treatment
- Antibody deficiencies -antibiotics, antibody replacements
- Granulocyte deficiencies - antibiotics, stem cell transplantation
- Severe combines immunodeficiency - stem cell transplantation, gene therapy
201
List some examples of secondary immunodeficiency
1. HIV
2. Irradiation and chemotherapy treatments
3. Removal of spleen
202
List the articulations of the wrist joint
- Distally - the proximal row of the carpal bones
| - Proximally - the distal end of the radius and the articular disc
203
Why is the ulna not part of the wrist joint?
It articulates with the radius just proximal to the wrist joint, at the distal radioulnar joint. It is prevented from articulating with the carpal bones by a fibrocartilaginous ligament, called the articular disk, which lies over the superior surface of the ulna
204
List the carpal joints of the wrist
Anticlockwise from scaphoid:
- Scaphoid
- Lunate
- Triquetrum
- Pisiform
- Hamate
- Capitate
- Trapezoid
205
Describe the structure of the joint capsule of the wrist joint
- Dual layered
- Fibrous outer layer which attaches to the radius, ulna and the proximal row of the carpal bones
- Internal layer = synovial membrane, secretes synovial fluid which lubricates the joint
206
List the important ligaments of the wrist joint
1. Palmar radiocarpal ligament
2. Dorsal radiocarpal ligament
3. Ulnar collateral ligament
4. Radial collateral ligament
207
Describe the blood supply to the wrist joint
Recieves blood from branches of the dorsal and palmar carpal arches, which are derived from the ulnar and radial arteries
208
Describe the innervation to the wrist joint
Supplied by branches of 3 nerves:
1. Median nerve - anterior interosseous branch
2. Radial nerve - posterior interosseous branch
3. Ulnar nerve - deep and dorsal branches
209
List the types of movements possible at the wrist joint
- Flexion
- Extension
- Adduction
- Abduction
210
List the joints of the hand
1. Carpometacarpal joints
2. Metacarpophalangeal joint
3. Interphalangeal joints:
- Proximal interphalangeal joints
- Distal interphalangeal joints
211
Metacarpals
5 miniature long bones, support the palm of the hand
212
Phalanges
- 14 miniature long bones of the digits, 3 in each finger, 2 in the thumb
- Proximal, middle and distal
213
List the movements possible in the hand
- Flexion of digits
- Extension of digits
- Abduction of digits
- Adduction of digits
- Opposition of thumb + little finger
- Reposition of thumb and little finger
214
Describe the structure of the palmar fascia
Fibrous connective tissue which thickens in the centre of the hand forming the palmar aponeurosis which is continuous with the palmaris longus tendon and flexor retinaculum
215
Palmar aponeurosis
- Protects the underlying muscle compartments
| - Fans out distally into four digital rays which then become the fibrous digital sheaths
216
Fibrous digital sheaths
Cover the synovial sheaths (containing the flexor tendons) in the digits and keep them in place.
217
List the important ligaments of the hands
1. Flexor retinaculum
2. Extensor retinaculum
3. Palmar (volar) plates
4. Collateral ligaments
218
List the important tendons of the hands
1. Flexor tendons of the digits - flexor digitorum profundus and flexor digitorum superficialis
2. Extensor tendons of the digits - extensor digitorum
219
Describe the blood supply of the hands
- Supplied by branches of the ulnar and radial arteries
- Anastomose near the wrist via 4 arches, branches supply the digits
- Deep palmar arch
- Palmar metacarpal arteries
- Superficial palmar arch
- Dorsal carpal arch
- Dorsal metacarpal arteries
- Digital arteries
Venous drainage:
- Dorsal venous arch
