MSK Flashcards
1
Q
What is a saphenous cutdown and when might it be important?
A
Great saphenous vein can be located anterior to medial malleolus, skin incision can be made here in emergency situations when difficult to find a vein for venepuncture or cannula insertion e.g. if patient in shock.
2
Q
Why might a patient experience pain over medial border of foot after a saphenous cutdown
A
Risk of saphenous nerve damage in procedure, which provides sensory innervation to medial border of foot so pain here if nerve damaged.
3
Q
Describe a Pott’s fracture
A
Excessive eversion of foot, pulls on medial ligament, tearing off medial malleolus-fractures. Talus moves laterally, shearing off the lateral malleolus. This can result in breakage of fibula superior to tibiofibular syndesmosis. Posterior margin of distal end of tibia may also be sheared off by talus.
4
Q
Borders of femoral triangle
A
Superiorly- inguinal ligament
Medially- medial border of adductor longus muscle
Laterally- medial border of sartorius muscle
Floor- pectineus muscle medially and iliopsoas muscle laterally
Roof- fascia latae (deep fascia)
5
Q
Borders of axilla
A
Apex- cervico-axillary canal- lateral border of 1st rib, post. border of clavicle and superior edge of scapula.
Anterior- pectoralis major and minor muscles.
Posterior- latissimus dorsi, teres major and subscapularis muscles.
Base- subcutaneous tissue, concave skin and axillary fascia.
Medial- serratus anterior muscle, ribs 1-4 and intercostal muscles.
Lateral- intertubercular groove in humerus.
6
Q
Describe the difference between the mid-inguinal point and the mid-point of the inguinal ligament, and state which is used to find the femoral arterial pulse.
A
MIP: the mid-point between the ASIS and the pubic symphysis. This is used to palpate the femoral artery. MP of IL: the mid-point between ASIS and pubic tubercle, as these are the attachment sites of the inguinal ligament. Femoral nerve located here.
7
Q
A patient has a +ve Trendelenburg test when standing on their right leg. If they were to stand on their right leg, lifting their left off the ground, which hip would drop down and which side would there be superior gluteal nerve damage.
A
Their left hip would drop (pelvis on unsupported side descends), and superior gluteal nerve damage on right side, so gluteus medius and minimus weak on supported side.
8
Q
Aside from superior gluteal nerve damage, give 2 other causes of a +ve Trendelenburg test.
A
Fracture of greater trochanter and dislocation of hip joint.
9
Q
Tensor fasciae latae muscle is a flexor of thigh and aids gluteus medius and minimus, but describe one other important function of this muscle.
A
Tenses iliotibial tract which inserts onto lateral condyle of tibia, so knee joint is stabilised, reducing work load of quads when standing and increasing extending force of knee when fully extended. Also supports femur on tibia when standing if lateral sway occurs.
10
Q
Which ligament gets thinner as descends VC?
A
Posterior longitudinal ligament.
11
Q
What test would you use to map dermatomes?
A
Pin prick test.
12
Q
What is the significance of the saphenous opening?
A
A femoral hernia can come through this opening.
13
Q
What key action cannot be performed, apart from dorsiflexion of foot, if common fibular nerve damage?
A
Eversion of foot as evertors in lateral compartment of leg, innervated by superficial fibular nerve.
14
Q
Why must the scapula rotate on abduction of arm above 90 degrees?
A
Greater tubercle of humerus impinges upon the acromion process of the scapula.
15
Q
Describe the course of the sciatic nerve
A
Enters gluteal region via greater sciatic foramen, inferior to piriformis, mid way between PSIS and ischial tuberosity. Descends into thigh vertically at midpoint between ischial tuberosity and greater trochanter. Nerve runs infero-laterally.
16
Q
Borders of cubital fossa
A
Roof- bicipital aponeurosis
Floor- supinator and brachialis muscles
Medial border- pronator teres
Lateral border- brachioradialis
17
Q
Contents of cubital fossa
A
Lateral to Medial: radial nerve, tendon of biceps brachii, brachial artery, median nerve. (RBBM)
18
Q
Contents of femoral triangle
A
Lateral to Medial: NAVY: femoral nerve, femoral artery, femoral vein, femoral canal
19
Q
Borders of anatomical snuffbox
A
Medial: tendon of extensor pollicis longus muscle
Lateral: tendons of abductor pollicis longus and extensor pollicis brevis muscles
Floor: scaphoid and trapezium and distal ends of tendons extensor carpi radialis longus and brevis.
Proximal: radial styloid process
Roof: skin
20
Q
Nerve roots for femoral and obturator nerves
A
L2-L4
21
Q
Nerve roots for sciatic nerve
A
L4-S3
22
Q
Blood supply to hip
A
Medial and lateral circumflex femoral arteries derived from the deep artery of the thigh(deep femoral artery), obturator artery and intra-medullary supply?
23
Q
Name components of axial skeleton
A
Skull, sternum, ribs, vertebrae and sacrum
24
Q
Name components of appendicular skeleton
A
U+L limbs, including clavicles and scapulae, and hip bones.
25
What is the quadrangular space bordered by and name the nerve that passes through this space. Also describe why there may be loss of sensation over regimental badge area if there is an anterior dislocation of the humerus at the shoulder joint.
Teres major+minor, humerus and long head of triceps brachii.
Axillary nerve
Subglenoid displacement of humeral head into quadrangular space damages the axillary nerve which provides sensory innervation to the regimental badge area via the superior lateral cutaneous nerve of the arm.
26
What action might a patient not be able to perform and why if an anterior dislocation of shoulder joint?
Abduction of the arm between 15 and 90 degrees as deltoid muscle responsible for this action may be paralysed in an anterior dislocation of shoulder joint as axillary nerve innervating the muscle is damaged.
27
Name 3 ways in which the axillary nerve may be damaged.
Surgical neck fracture of humerus, dislocation of GH joint, improper use of crutches.
28
Give nerve roots for axillary nerve
C5, C6
29
Give nerve roots of musculocutaneous nerve and name the muscles it innervates
C5,C6,C7
| Anterior arm compartment: biceps brachii, coracobrachialis, brachialis
30
How might musculocutaneous nerve be damaged?
| What would be the consequence?
Weapon injury to axilla e.g. knife injury.
Paralysis of BBC, and may be loss of sensation over lateral aspect of forearm supplied by lateral cutaneous nerve of forearm, the continuation of the musculocutaneous nerve.
31
Give nerve roots of radial nerve and describe when it might be damaged
C5-T1.
May be damaged superior to origin of its branches to triceps brachii.
May be damaged in a mid-shaft fracture of humerus where it travels in the radial groove.
May be when deep wounds of forearm, as this can damage the posterior branch of the radial nerve which is an entirely muscular branch.
32
Define a callus and give 2 of its functions
a fibrocartilaginous structure, which helps to stabilise bone and bind the 2 bone ends together. Fibroblasts undergo metaplasia to form chondroblasts which lay down islets of cartilage around collagen fibres, forming a DCT.
33
Why might the healing of bone fractures be delayed?
- pre-existing bone disease
- movement so bone unstable
- infection
- intersposed soft tissue
- gross mis-alignment
34
Define compartment syndrome and state how it can be relieved
condition resulting from swelling of muscles in a limb compartment which raises pressure within compartment so blood supply to muscle cut off, causing ischaemia and further swelling. New blood can't be supplied to area as arterial pressure becomes greater than pressure supplying blood.
Fasciotomy
35
Give 4 causes of compartment syndrome
bone fracture, crush injury, tight plaster, extreme exercise
36
What are the origins and attachments of the biceps brachii muscle?
Long head originates from the supraglenoid tubercle of the scapula whereas short head originates from the coracoid process of the scapula. Both heads insert via a tendon onto the radial tuberosity of the radius.
37
What are the attachments of the flexor retinaculum at the wrist?
Scaphoid, trapezium(tubercles of both), pisiform and hamate (hook of) carpal bones.
38
What are the origins and attachments of the biceps brachii muscle?
Long head originates from the supraglenoid tubercle of the scapula whereas short head originates from the coracoid process of the scapula. Both heads insert via a tendon onto the radial tuberosity of the radius.
39
Which veins does the median cubital vein connect?
The basilic (medially) and the cephalic (laterally) veins.
40
Which major artery supplies most of the arterial branches to the scapula? If this artery were to be occluded at its mid point, how would blood be allowed to reach the arm?
Axillary artery
| Arterial anastomosis/collateral circulation around scapula.
41
Which veins does the median cubital vein connect?
The basilic (medially) and the cephalic (laterally) veins.
42
Which major artery supplies most of the arterial branches to the scapula? If this artery were to be occluded at its mid point, how would blood be allowed to reach the arm?
Axillary artery
| Arterial anastomosis/collateral circulation around scapula.
43
Which muscle, acting on scapula, would be affected by injury of spinal accessory nerve?
Trapezius
44
Give an example of an irregular bone in UL?
Trapezium (carpal bones)
45
Flat bone in UL?
Scapula
46
Mechanical functions of bone?
- Support of soft tissues as rigid framework.
- Protection of vital organs
- Movement as anchoring points for muscles and acts as levers at joints.
- Shape given to individual
47
How do tuberosities, tubercles, ridges and grooves appear on a long bone?
Mechanical forces due to ligaments, tendon, fascia and aponeurosis attachment. Pressure from adjacent structures e.g. nerves and blood vessels, creates grooves.
48
Physiological functions of bone?
- Storage of salts and minerals, so aids homeostasis.
- Lipid storage in emergencies-yellow marrow
- Supply of blood cells, red marrow-erythropoiesis.
49
Name causes of a swelling in the popliteal fossa.
- Enlarged lymph nodes
- Popliteal arterial aneurysm
- Popliteal cyst (Baker's)
- Tumour
- Abscess
50
What name is given to the regional thickenings of deep fascia at the ankle joint which prevent the tendons of muscles in the anterior compartment from bowstringing out during contraction?
Superior and inferior extensor retinacula.
51
What is the function of red bone marrow and erythropoietin?
Red BM- erythropoiesis. Erythropoietin- cytokine released by the kidneys in response to a decrease in pO2, and this stimulates rbc production, causing differentiation of common myeloid progenitor cells into rbc.
52
Define a dermatome
a unilateral area of skin supplied by the sensory nerve fibres of a single spinal nerve root.
53
Define a myotome
a muscle or group of muscles supplied by the motor nerve fibres of a single spinal nerve root.
54
Define the 3 classes of joints based on their function and describe each, also giving an example for each.
Synarthrosis- an immovable joint in which bones connected by fibrous tissue e.g. interosseous membrane between radius and ulna=syndesmosis. Also gomphoses-teeth and sutures-skull.
Amphiarthrosis- slightly moveable joint in which bony surfaces separated by hyaline cartilage e.g. epiphyseal growth plates-synchondrosis, or fibrocartilage e.g. pubic symphysis.
Diarthrosis- freely moveable joint with ends of adjoining bones covered in hyaline (articular) cartilage sheet e.g. glenohumeral joint-ball and socket synovial joint.
55
Give the 7 different types of synovial joint
Ball and socket, condylar, hinge, pivot, saddle, ellipsoid and plane.
56
Classifly the 3 types of joints in terms of structure and describe them.
Fibrous- articulating bones united by fibrous tissue, virtually no movement e.g. tight union between bones of adult skull.
Cartilaginous- articulating bones connected by hyaline or fibrocartilage. Primary and secondary, primary usually temporary, little movement permitted.
Synovial- freely moveable, skeletal element separated by a cavity, hyaline cartilage covering articulating bone surfaces.
57
3 main components of all synovial joints
- joint cavity with small amount of synovial fluid
- articular hyaline cartilage covering articulating bone surfaces separated by joint cavity.
- synovial membrane which secretes synovial fluid and lines the outer fibrous layer of the joint capsule.
58
What factors restrict movement at synovial joints?
Ligaments-these exert a tension e.g. iliofemoral ligament of hip. Muscle tension.
Interference by other structures.
Stability dependent on depth of bony articulations.
59
Which specific tissues affected in RA and osteoarthritis?
RA: synovium
Osteo: cartilage
60
What is the significance of a lump being fixed?
Attached to other tissues e.g. muscle, skin or deep fascia. This may indicate an invasive an malignant pathology.
61
Which nerve supplies the muscles of the lateral compartment of the leg, and name these muscles.
Superficial fibular nerve
| Fibularis longus and brevis
62
Which arteries supply blood to the lateral compartment of the leg?
Perforating branches of the anterior tibial artery and the fibular artery.
63
What are the functions of the muscle in the lateral compartment of the leg?
Eversion, and assist with plantarflexion.
64
Name the muscles of the anterior leg compartment, and give the main functions of this compartment.
Tibialis anterior, extensor hallucis longus, extensor digitorum longus, fibularis tertius.
Dorsiflexion of the ankle, inversion of foot and extension of toes. Fibularis tertius performs eversion of the foot.
65
Which artery supplies blood to the anterior leg compartment?
Anterior tibial artery
66
Which nerve innervates the muscles of the anterior leg compartment?
Deep fibular nerve
67
What function does eversion facilitate?
Walking on an uneven surface
68
Name the extracapsular ligaments of the knee joint
Medial and lateral collateral, patellar, oblique popliteal and arcuate popliteal.
69
Name the intracapsular ligaments of the knee joint
Anterior and posterior cruciate
70
Which ligament is the strongest intracapsular ligament of the knee joint?
posterior cruciate
71
Which muscle contribute to the forming of the calcaneal (achilles) tendon, and where does this tendon insert?
Medial and lateral heads of gastrocnemius, soleus.
| Calcaneus bone
72
Describe varicose veins
In the lower limbs, blood flows from the skin to superficial veins, which drain into the deep veins. Valves prevent back flow of blood. If they become incompetent, the superficial veins can become dilated, and tortuous. There are various soft tissue changes that can occur with chronic varicose veins. Due to the incompetence of the valves, the pressure in the venous system rises. This damages the cells, causing blood to extrude into skin. Further complications can produce a brown pigmentation, and ulceration can occur. Varicose veins can be treated by;
- Surgical movement of the saphenous systems
- Reconstruction of valves
- Tying off the affected valves
73
Name the 2 articulations of the knee joint and what type of synovial articulations these are.
tibia-femoral articulation:hinge
| patello-femoral :plane
74
Describe the unhappy triad of injuries of the knee joint.
Medial collateral ligament tear, along with tearing of medial meniscus and tearing of the anterior cruciate ligament.Frequently results from blow to lateral side of extended knee or excessive lateral twisting of the flexed knee that disrupts ligament, common in athletes e.g. in basketball, who twist their flexed knees when running.
75
How might a patient with a scaphoid fracture present?
With pain over the anatomical snuffbox. Fracture may not be visible on an X-ray, but may be around 10 days later when bone resorption has started to take place.
76
Why might someone with a scaphoid fracture end up with avascular necrosis?
Scaphoid fractures across its waist, so blood supply to the proximal fragment is cut off as the fragment is separated from where the blood is supplied to the bone as all the blood supply to the proximal part of scaphoid enters at or just distal to the waist so distal to proximal blood flow.
77
What 2 structures may be damaged in a mid-shaft humeral fracture?
Radial nerve and profunda brachii artery (deep brachial artery).
78
Name the articulating surfaces of the ankle joint.
inferior surface of tibia, deep surface of medial malleolus of tibia and deep surface of lateral malleolus of fibula, and body of talus.
79
Between which bones is the subtalar joint?
Talus and calcaneus
80
What other name is given to the medial collateral ligament of the ankle joint?
Deltoid ligament
81
What functions does the posterior cruciate ligament have?
Prevents hyperflexion of knee joint, limits anterior rolling of femur on tibia, and anterior displacement of femur on tibia.
82
What functions does anterior cruciate ligament have?
Prevents hyperextension of knee joint, prevents posterior displacement of femur on tibia. Tibia cannot be pulled anteriorly when joint flexed at 90 degrees as held in place by ligament.
83
What name is given to the remnant of the notochord in the adult?
nucleus pulposus
84
What are pectoralis major and minor innervated by?
```
Major= medial and lateral pectoral nerves
Minor= medial pectoral nerve
```
85
What actions does pectoralis major perform?
Adduction, flexion and medial rotation of arm at GH joint.
86
Describe the action of calcitonin
Involved in preserving the maternal skeleton during pregnancy. Released from parafollicular cells of thyroid gland. Trigger protein. Stimulates activity of osteoblasts and inhibits osteoclasts.
87
How might Vit A deficiency affect bone?
Imbalance in ratio of osteoblasts and osteoclasts, resulting in a slowing of growth rate.
88
How might Vit C deficiency affect bone?
growth inhibited as insufficient prod. of collagen and bone matrix, bone weak, and delayed healing of broken bones. Vit C essential for strong triple helical structure of collagen.
89
What may be compressed by the coracoid process in the axilla?
Subclavian vein, subclavian artery, cords of BP.
90
Why would the right radial pulse be weak if there were compression of the right subclavian artery?
Compromised blood supply to UL as subclavian artery continues as the axillary artery as it passes the lateral border of the 1st rib, then it continues as the brachial artery as it passes the inferior border of teres major. This artery bifurcates into the radial and ulnar arteries in the lower part of the cubital fossa. Both radial and ulnar pulses will be weak as blood supply to both these arteries is from the subclavian artery.
91
State the action of pectoralis minor
Stabilises the scapula by drawing it inferiorly and anteriorly against the thoracic wall.
92
Define amelia
Complete absence of 1 or more limbs (extremities).
93
Define meromelia
Partial absence of 1 or more of the extremities.
94
Explain the condition polydactyly
1 or more digits present, usually bilateral, and result of a genetic recessive trait. Often, extra digit is incompletely formed, and lacks proper muscle fixation. In the hand, the extra digit is either on ulnar or radial side, rather than central, foot- fibular side.
95
What are the nerve roots of the phrenic nerve?
C3, C4 and C5
96
How does skeletal muscle relax?
Return of Ca2+ to intacellular stores by active transport into sarcoplasmic reticulum via SERCA.
97
How does increase in IC Ca2+ produce symptoms of muscle rigidity?
Crossbridge cylce activated between myosin and actin, promoting contraction. Sustained Ca2+ release counteracts process of reuptake, necessary for relaxation.
98
List clinical signs of a large increase in body metabolism.
- Increase in body tem.
- Decrease in blood O2
- Increase in blood CO2
- Increase ventilation
- Decrease blood pH
- Tachycardia
99
Which structures are contained within the axillary sheath?
Axillary artery and vein.
| Brachial plexus- cords and branches
100
Why concern over enlargement of axilla lymph nodes in a female.
May be indicative of breast cancer, as axillary lymph nodes receive approx. 75% of breast lymoh and so will also receive metastatic breast cancer cells if present, causing node enlargement, with cancerous cells entering the lymph vessels and passing into axilla lymph.
101
Name nerves supplying flexor muscles of arm and forearm.
Musculocutaneous, Median, Ulnar and Radial-brachioradialis!
102
What are the cords of the BP named with respect to?
Axillary artery
103
Which vein lies immediately posterior to sternoclavicular joint?
Brachiocephalic
104
What is the function of the clavicle?
Rigid support from which scapula and UL suspended, connects UL to trunk, keeps scapula and UL away from thorax, allowing arm to have max. freedom of movement.
105
Describe what happens when the clavicle fractures.
Most common fracture site= junction between medial 2/3 and lateral 1/3. Medial bone fragment elevated by sternocleidomastoid muscle. Trapezius unable to hold up lateral fragment due to weight of UL, so shoulder drops. Lateral fragment may also be pulled medially by adductor arm muscles e.g. pec. major.
106
Describe subacromial bursitis.
Inflammation of bursa, causing pain, tenderness and limited movement of GH joint. May result from Ca2+ deposition in supraspinatus tendon, causing increased local pressure that causes pain on arm abduction and can irritate overlying subacromial bursa. Painful lesion away from inferior surface of acromin when arm adducted but pain between 50 and 130 degrees of abduction- painful arc syndrome, as supraspinatus tendon in contact with inferior surface of acromion. May occur after excessive GH joint use, usually in in males aged 50 or older.
107
Name the rotator cuff muscles and their innervations.
Supraspinatus- suprascapular nerve
Infraspinatus- suprascapular nerve
Teres minor- axillary nerve
Subscapularis- upper and lower subscapular nerves
108
What innerates the rhomboids? What other muscle does this nerve innervate?
Dorsal scapular nerve
| Levator scapulae
109
What innervates latissimus dorsi?
Thoracodorsal nerve
110
If bleeding from a large vessel as result of fracture, how would you tell if blood from an artery or vein?
Artery: pulsatile release of blood. If major artery damaged, patient most likely unconscious or dying.
Vein: non-pulsatile, patient concsious, haematoma forming if not an open wound.
111
Explain syndactyly.
2 or more fingers or toes fused together. Some error in sculpting process when mesenchyme between prospective digits removed by apoptosis. Thinner tissue between digits does not break down. Bones may also be fused. Most often 3rd and 4th fingers, and 2nd and 3rd toes.
112
Describe difference between cutaneous and osseous syndactyly.
Cutaneous: webbing of skin between fingers and toes as failure of tissue breakdown, but osseous: bones also fused in addition to tissue.
113
What structural defect underlies congenital hip dislocation?
Underdevelopment of acetabulum and head of femur.
114
Which muscles cause elbow flexion?
Biceps brachii
Brachialis
Brachioradilais
115
Which structure lies immediately anterior to brachial artery and median nerve in cubital fossa?
Bicipital aponeurosis
116
Describe cubital tunnel syndrome
Compression of the ulnar nerve as it passes between the 2 heads of flexor carpi ulnaris to enter the forearm.
117
What is subcutaneous olecranon bursitis and how does it occur?
Bursa lying between skin and olecranon process becomes inflamed, as repeated excessive pressure and friction. May become infected and skin area superficial to it may become inflamed.
118
How is shoulder joint stabilised?
- Tone of rotator cuff muscles
- Extracapsular and capsular ligaments
- Glenoid labrum
119
In which direction does the humeral head normally dislocate and why?
Inferiorly as poorly supported inferiorly. Classed as an anterior dislocation as head locates anteriorly by pull of powerful adductor muscles.
120
How is the superior displacement of the humeral head prevented?
Coraco-acromial arch
121
Where is the anatomical neck of the humerus and describe its significance.
Formed by groove circumscribing and separating head of humerus from greater and lesser tubercles.
Articular joint capsule attached nearby.
Marks region of epiphyseal growth plate during growth in humeral length.
122
List the 6 scapula movements.
```
Elevation
Depression
Protraction
Retraction
Upward rotation (lateral)
Downward rotation (medial)
```
123
What would happen in the clinical exam of a patient with a torn supraspinatus tendon?
Failure of initiation of abduction of arm to 15 degrees. When person asked to lower a fully abducted arm slowly + smoothly, then from approx. 90 degrees arm drops suddenly to side in an uncontrolled manner. Tendon tears due to degenerative tendonitis as relatively avascular.
124
What is the significance of the subacromial bursa?
Facilitates movement of supraspinatus tendon under coraco-acromial arch and of deltoid over GH joint capsule and greater tubercle of humerus. Tendon separated from coraco-acromial ligament, deltoid and acromion.
125
Where does pectoralis major insert?
Intertubercular sulcus of humerus
126
Anatomical significance of femoral canal
Site of femoral herniation.
| Allows femoral vein to expand if increased venous return to heart and if increased intra-abdominal pressure.
127
What forms the base of the femoral canal?
The femoral ring
128
What are the boundaries of the femoral ring?
Anteriorly- inguinal ligament
Posteriorly- superior ramus of pubis
Medially- lacunar ligament
Laterally- vertical septum between femoral canal and femoral vein
129
What nerve damage and muscle weakness cause winged scapula?
Long thoracic nerve and serratus anterior
Medial border of scapula and inferior angle project from post thoracic wall when arm pushed against a wall. Can occur in axillary clearance.
Unopposed action of muscles e.g. rhomboids on medial border of scapula
130
Nerve most likely to be damaged in mid-shaft humeral fracture
Radial nerve as closely associated with bone as tightly bound in radial groove on posterior surface of humerus
131
Why would mid-shaft humeral fracture result in weakened extension of elbow?
Radial nerve innervates triceps brachii which performs elbow extension. Branches of nerve to long and lateral heads of muscle will have come off before region of nerve damage but the medial head of the muscle will be paralysed
132
Why would poor wrist and finger extension occur with midshaft humeral fracture
Wrist drop as radial nerve damage- innervates all extensors of wrist and fingers, these muscles would all be parlaysed, so unopposed flexion and gravity
133
Describe a pulled elbow and why it happens more often in children
subluxation of head of radius from annular ligament. Ligament much softer in children, bones of elbow joint not fully ossified and so radial head also not fully formed, and children swung by their arms in a pronated position
134
why is supination more powerful than pronation
strength of biceps brachii and supinator greater than that of pronator teres and quadratus, supinator muscles have a greater cross-sectional area
135
Anatomical snuff box boundaries?
Proximal- styloid process of radius
medial-tendon of extensor pollicis longus muscle
lateral- tendons of extensor pollicis brevis and abductor pollicis longus
floor- scaphoid and trapezium
roof- skin of dorsum of hand
136
Scaphoid fracture: x-ray several wks after, what would it show if proximalsegment beginning to be resorbed?
Will look less opaque
137
Abductors of wrsit?
flexor carpi radialis, extensor carpi radialis longus and brevis
138
Why is it difficult to form a fist following radial nerve lesion?
wrist drop- unopposed action of flexors
139
blood supply to lateral compartment of leg?
perforating branches of anterior tibial and fibular arteries
140
presentation of a Colle's fracture?
dinner fork deformity
posterior displacement of distal 2.5cm of radius, with radial shortening and possible shearing off of styloid process of ulna
141
how does mechanism of injury differ between colle's and smith's fracture
fall on extended vs flexed wrist
142
bone matrix composition?
type 1 collagen, provides strength and flexability
| hydroxyapatite crystals
143
extracapsular ligaments of hip?
iliofemoral- strongest, anteriorly
pubofemoral
ischiofemoral
144
extracapsular ligaments of hip?
iliofemoral- strongest, anteriorly
pubofemoral
ischiofemoral
145
innervation of muscles in anterior thigh compartment?
femoral nerve L2-L4
146
innervation of muscles in anterior thigh compartment?
femoral nerve
147
what do the hamstrings do?
extend hip and flex knee
but short head of biceps femoris only extends the knee
innervated by tibial part of sciatic nerve apart from short head- common fibular part of sciatic nerve
148
what happens to the median nerve at the wrist?
becomes superficial in midline, gives off a palmar cutaneous branch which supplies skin of midpalm
149
what do the ulnar and median nerves motor supply in hand?
Ulnar: hypothenar compartment, adductor pollicis, interossei, 3rd and 4th lumbricals
Median: thenar, 1st and 2nd lumbricals
150
safe site for gluteal IM injections?
upper lateral quadrant
151
what is the pubic tubercle part of?
the superior ramus of the pubis
152
functions of extracapsular ligaments of hip joint?
iliofemoral- prevent hyperextension during standing
pubofemoral- prevents excessive abduction
ischiofemoral- supports post hip aspect, can prevent hyperextension
153
where do extracapsular hip fractures occur?
beyond the trochanters
154
where do intracapsular hip fractures occur?
fractures of femoral neck involving bone within the margins of the capsule which is attached to the acetabulum, neck of femur, intertrochanteric line and crest
155
why does the thigh rotate medially with a dislocation of the hip joint?
anterior parts of gluteus medius and minimus pull on the greater trochanter and cause the thigh to rotate medially
156
3 bony landmarks for course of the sciatic nerve(L4-S3)?
PSIS
ischial tuberoisty
greater trochanter
157
what converts the greater and lesser sciatic notches into foramina?
sacrotuberous and sacrospinous ligments
limit upward movement of inferior part of sacrum during transmission of weight of body down VC in erect posture
158
how is the C shaped curvature of the newborn brought back with old age?
IV disc atrophy
159
anatomical abnormalities of VC in spina bifida?
laminae of lower L vertebrae and upper sacral vertebrae fail to develop normally and fuse, so spinal nerves or even SC may protrude backward out of the defect in the post midline of VC
160
how is stability of VC achieved?
resistance of A and P longitudinal ligaments, and back muscles resistance, thickness and compressability of IV discs, and shape and orientation of vertebral joints
161
why are limited movements in thoracic region of VC?
attachments to sternum via ribs and costal cartilages
162
why are C vertebrae damaged in whiplash injuries?
vertebrae have a relatively free range of movement due to thin IV discs and loose articular capsules, and ligaments connecting vertebrae are short and thin. Sudden forceful flexion and extension can tear the thin connecting ligaments to cause vertebrae dislocation anter or poster.
163
where do the gluteal nerves originate from?
lumbo-sacral plexus L4-S1
164
superior gluteal nerves, superior to what on entry through greater sciatic foramen?
piriformis
165
what is true limb shortening
actual loss of bone length
166
false limb shortening?
due to problems with vertebrae, fixed flexion deformity or pelvic tilt
167
functions of knee locking?
weight bearing when full knee extension
| thigh and leg muscles can relax briefly without making the joint too unstable
168
how is the knee unlocked?
contraction of popliteus causing lateral rotation of femur on the fixed tibia in order for the knee to be flexed
169
what do menisci comprise?
fibrocartilage, crescenteric shaped
170
functions of menisci?
shock absorbers
| deepen articular surface of tibia for femoral condyles
171
why is medial meniscus more commonly torn?
weaker medial collateral ligament, and meniscus is attached firmly to this so tearing of ligament due to lateral trauma of knee causes excessive medial displacement of tibia, tearing ligament and meniscus
172
what is housemaids knee?
prepatellar bursitis, result of friction between skin and patella
173
what is clergyman's knee?
subcutaneous infrapatellar bursits, caused by excessive friction between skin and tibial tuberosity
174
why is there a greater risk of infection with a compound fracture?
skin over fracture site is broken, so break in skin can be exploited by pathogens in external environment
175
what is a pathological fracture?
fracture of abnormal bone- bone that has been weakened already by some underlying bone disease, so less force is necessary to cause a fracture
176
what causes a stress fracture?
overuse injury of bone, bone fatigued by repetitive stress
177
joints of inversion and eversion?
subtalar
| calcaneocuboid
178
why does a kick on the shin hurt so much?
surface of tibia along medial aspect only has subcutaneous soft tissue
and bone covered by periosteum which has a rich nerve supply
179
sensory innervation to little toe?
sural nerve
180
which ligament is most commonly affected in inversion injuries at the ankle?
anterior talofibular ligament
181
why does the foot in a child appear to be flat?
thick subcutaneous fat pad in the sole
| arches not developed fully
182
consequences of common fibular nerve damage and when is it most likely to be damaged?
foot drop- high steppage gait, as unable to dorsiflex at ankle joint
can't evert foot
tight plaster cast
bumper car injury
as nerve relatively superficial as it winds around the neck of the fibula
183
serratus anterior action on scapula?
protraction, so held against thoracic wall
| rotation, so can abduct arm at GH joint above 90 degress
184
immediate concern if patient presents with a a very red, painful swollen knee?
septic arthritis**why emergency?
185
features of RA in hands?
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swollen MCP joints
ulnar deviation of fingers Z-deformity of thumb
loss of valley between knuckles
rheumatoid nodules
palmar erythema
boutonniere deformity of thumb
fixed flexion deformity?
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186
X-ray features of RA?
bone erosions
soft tissue swelling
joint subluxation- result of inflammation rupturing tendons
osteopenia
187
X-ray features of OA?
loss of joint space
subchondral sclerosis and cysts
osteophytes
188
describe 2 clinical tests that can be used in diagnosing carpal tunnel syndrome
Tinel's sign= lightly tap over the median nerve to elicit a sensation of tingling or "pins and needles" in the distribution of the nerve= lateral 3 and a half digits
Phalen's test= Ptnt holds their wrist in complete and forced flexion (pushing the dorsal surfaces of both hands together) for 30–60 seconds. The lumbricals attach in part to the flexor digitorum profundus tendons. As the wrist flexes, the flexor digitorum profundus contracts in a proximal direction, drawing the lumbricals along with it. The lumbricals can be "dragged" into the carpal tunnel with FDP contraction. As such, Phalen's maneuver can moderately increase the pressure in the carpal tunnel via this mass effect, pinching the median nerve between the proximal edge of the transverse carpal ligament and the anterior border of the distal end of the radius, producing the tingling painful sensation in lateral 3 and a 1/2 digits= +ve test.
189
RFs for carpal tunnel syndrome?
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TRAMP
tenosynovitis, trauma
RA, repetitive strain
acromegaly
myxoedema
pregnancy
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