MSK anatomy Flashcards
What are the adductor muscles of the leg and their innervations
gracilis, obturator externus, adductor brevis, adductor longus and adductor magnus. Innervation all by obturator nerve (L2-L4)
What does the deep peroneal nerve supply
Anterior compartment of the lower leg. Damage causes inability to dorsiflex and loss of sensation between 1st and 2nd webspaces.
What muscle does Jobe’s test for
Supraspinatus
What protein mutation is in marfans syndrome
Fibrillin-1
What is the typical nerve damage in a medial supracondylar fracture
Ulnar nerve
Where does the ulnar nerve run in relation to the humerus
Posterior to the medial epicondyle
What controls adduction of the thumb
Ulnar nerve
What nerve damage causes loss of sensation to hypothenar eminecne
Ulnar nerve
Cause of plantar fasciitis
Chronic overuse of feet leading to microtears of plantarfascia. Tenderness on medial side of heel where medial tuberosity of calcaneus is
Rock, paper, scissors analogy
Finger flexion, extension and finger abduction and adduction: medial, radial and ulnar
What extends the first 3 digits, what extends the last 2 digits
Radial then ulnar
Saturday night palsy is damage to which nerve
Radial
How would median nerve damage occur
Supracondylar fracture
How would ulnar nerve damage occur
Outstretch fall or medial epicondyle fracture
Manifestation of radial nerve injury
Wrist drop (rist drop)
What is osteochondroma
Benign bone tumour of bony outgrowth with cartilaginous cap. common in young people and can be caused by trauma.
Painless hard lump
Commonly near knee- distal femur/proximal tibia
Imaging- x-ray and MRI showing cartilagenous ossified pedicles.
MM- observation small risk of malignancy
What is endochondroma
Benign tumour due failure of normal endochondral ossification at the growth plate. Most commonly presents at 20-50.
Occurs in femur, humerus, tibia and small bones of hands and feet
Imaging- x-ray lesion can have sclerotic appearance
MM- can be scraped out
What is a single bone cyst
single cavity benign fluid filled cyst in bone probbaly due to growth defects in physis. Usually proximal humerus and femur.
Can weaken bone leading to pathological fracture.
Imaging- x-ray, MRI
MM- curettage and bone grafting, stabilisation may be required
What is an aneurysmal bone cyst
Consists of many chambers filled blood or serum. Can occur in many different long bones, flat bones and vertebral bodies
Painful mass/swelling, pathological fracture
Imaging- X-ray= chambers seen
MM- cuttarage and grafting or bone cement
What is a giant cell tumour of bone
Tumour of giant cells of bone
Occurs in metaphyseal regions but can extend to epiphysis. Locally aggressive
Painful mass/swelling. Commonly in knee and in distal radius, pelvis and spine
Imaging- x-ray= classic soap bubble appearance
MM- intralesional excision with use of phenol, bone cement or liquid nitrogen. if aggressive joint replacement may be needed
What is fibrous dysplasia
Developmental disorder of bone causing skeletal tissue to be replaced with fibrous tissue usually due to genetic mutation.
Bone pain and deformities, pathological fracture
Imaging- bone scan= increase uptake. Shepard crook defomity of x-ray
MM- bisphosphanates, fracture stabilisation
What is an osteoid osteoma
Benign bone tumour usually in children. Common sites are proximal femur, diaphysis of long bones and verterbrae
Intense constant pain worse at night, can be relieved by NSAIDs
Imaging- Bone scan and CT to confirm diagnosis- halo sign seen
MM- may resolve or CT guided radiofrequency ablation
What is osteosarcoma
Malignant bone producing tumour with blood spread.
Most seen in young people
Most involve the knee but can include proximal femur, proximal humerus and pelvis
X-ray
MM- surgery with joint construction, chemotherapy can prolong survival
What is chondrosarcoma
Malignant cartilage producing bone tumour
Older age group
Found in pelvis or proximal femur
What is Ewing’s sarcoma
Primary bone tumour of endothelial cells of the bone marrow
2nd most common malignant bone tumour in children
Characterised by loss of bone
Affects young people
Can mimic infection with hot, tender swollen joint
Usually found in diaphysis of long bones- distal femur, proximal femur
A T score of what suggests osteoporosis
-2.5
Osteopenia from -1 to -2.5
What are the median nerve roots
C5-T1
What innervates the supraspinatus muscle
Suprascapular nerve (C5-C6) (also innvervates infraspinatus)
What innervates the anterior compartment of the forearm
Median nerve except for flexor carpi ulnaris and median half of flexor digitorum profundus
Supercondylar fractures often lead to what damage
Brachial artery and median nerve injury
Pain at base of thumb with positive finklesteins test
De Quervains tenosynovitis- inflammation of tendon sheath s involving Abductor Pollicis Longus and Extensor Pollicis Brevis
What bone tumour has pain worse at night with a moth eaten pattern of bone destruction
Chondrosarcoma
What are the axillary nerve roots
C5 and C6
What are the radial nerve roots
C5-T1
What are ulnar nerve roots
C8-T1
What are the musculocutaneous nerve roots
C5, C6, C7
What structure is most at risk in a supracondylar fracture
Brachial artery
