Musculoskeletal and Connective Tissue Flashcards
Where does the ACL extend?
Lateral femoral condyle to the anterior tibia
where does the PCL extend?
From the medial femoral condyl to the posterior Tibia
What is the anterior drawer sign?
Bend knee at 90 degree angel
Anterior gliding due to ACL injury
What is the posterior drawer sign?
Bend at 90 degree angle (posterior gliding due to PCL injury)
Abnormal passive abduction?
Bend at 30 degrees Lateral valgus (external roatation) has MCL injury
Abnormal passive adduction
Knee extended at 30 degree angle (medial force means LCL injury
What is the McMurray text
Flexion and extension of the knee with rotation of the tibia and foot (the sounds will have external popping sound: medial meniscal tear
Pain: popping on internal rotation (lateral meniscal tear)
what is the unhappy triad of contact sports?
Lateral force applied to planted leg
Damage to : ACL, MCL and medial meniscus
(Can also have the lateral meniscus injury)
Will present with acute knee pain, and joint instability
what is prepatellar bursitis?
Inflammation of the knee’s largest sac of synovial fluid
Can be caused by repeated trauma of from excessive kneeling
What is a Baker’s cyst?
Popliteal fluid collection in the gatrocneimius -semi-membraneous bursa commonly communicating with the synovial space.
related to chronic joint disease
what are the muscles of the rotator cuff?
Supraspinatus (abducts arm initially) before the action of the deltoid
(most common rotator cuff injury)
Infraspinatus: laterally rotates the arm (pitching injury)
Teres minor: adducsts and laterally rotates the arm
Subscapularis: upper and lower subscapular nerves (medially rotates and abducts the arm)
innervated by C5 and C6
what is golfer’s elbow? (medial epicondylitis)?
Repetitive flexion (forehand shots) or idopathic Pain is near the medial epicondyle
Lateral epicondylitis: tennis elbow Repetitive extension (backhand shots) pain near the lateral epicondyle
What are the wrist bones?
Trapezium Trapazoid Capitate Hameta Triquetrium Pisiform Lunale Sacphoid
What is the most commonly fractured carpal bone?
The scaphoid
Usually due to fall on outstretched hand
Is prone to avascular necrosis due to retrograde blood supply
what is the carpal tunnel syndrome?
entrapement of the median nerve in carpal tunnel
leads to paresthesi, pain and numbness
Thenar eminence is atrophoed
What are diseases associated with the carpal tunnel syndrome?
Pregnancy RA Hypothyroidism Diabetes Dialysis related amyloidosis
What is the Guyon Canal syndrome?
Compression of the ulnar nerve at wrist or hand
Clasically seen in cyclists due to pressure from the handlebars
How is the axillar C5-C6 affected?
Fractured neck of the humerus, with anterior dislocation of the humerus
Will present with flattened deltoid
Loss of arm abduction at shoulder (15 degrees)
Loss of sensation over deltoid muscle and lateral arm
Injury to musculocutaneous C5-C7
Other forearm
Usually due to trunk compression
Loss of foreamr flexion and supination
Loss of sensation over the lateral portion of the forearm
Injury to the radial (C5-T1) ?
Midshaft fracture of the humerus
Compression of the axilla due to crutches or sleeping with the arm over chair
Wrist drop (loss of elbow)
Wrist and finger extension
Decreased in grip strength
Loss of sensation over the posterior arm and forearm of the dorsal hand
Injury to median nerve C5-T1?
Supracondylar fracture of the humerus (proximal lesion)
Carpal tunnel syndrome (wrist laceration)
Presents with the ape hand or the Pope’s blessing
Loss of wrist flexion, flexion of the lateral fingers, thumb opposition
Loss of sensation over the thenar eminence and dorsal palmer aspects of lateral 3/1/2 fingers
Tinel syndome: tingling on percussion in carpal tunnel syndrome
Injury to the Ulner C8-T1?
Fracture of the medial epicondyle of the humerus (funny bone…if proximal leision)
Fractured hook of hamate (distal lesion)
will have the ulnar claw on digit extension
Radial deviation of the wrist upon flexion (proximal lesion)
Injury to the recurrent branch of the median nerve 9C5-T1)?
Leads to Ape Hand
Loss of thenar muscle group (opposition) abduction, and flexion of the thumb
No loss of sensation
What is Erb’s palsy?
Injury of C5 -C6
Caused: lateral traction of the neck during delivery
Adults: Trauma
What is the muscle deficit and functional deficit:
Deltoid: abduction (arm hangs by the side)
Infraspinatus: lateral rotation (arm is medially rotated)
Biceps brachii: Flexion, supination (arm is extended and pronated)
Klumke palsy?
Traction or tear of the lower trunk (C8-T1)
Infants: upward force on the arm during delivery
Adults: trauma (grabbing a tree branch to break the fall)
Muscle deficit: Lumbricals Interossei Thenar Hypothenar
Leads to total hand clow
Thoracic outlet syndrome?
Compression of lower trunk and the subclavian vessels
Due to cervical rib, or the pancoast tumor
Causes atrophy of the intinsic hand muscles (ischemia, pain, and edema due to vascular compression)
What is the winged scapula?
Lesion of the long thoracic nerve
Due to axillary node dissection after the mastectomy
Stab wounds
Have inability to anchor the scapula to the thoracic cage (cannot abduct the arm above a horizontal position)
Describe the ulnar claw?
Pinkie and finger beside are pulled down
Due to distal ulner nerve injury
What is the Pope’s blessing?
Pinkie and finger beside are pulled down
Atrophy of the remaining fingers
What is the median claw?
Middle finger, to thumb are curled down
Distal median nerve compression
Ok gesture?
Pinkie and finger beside
What are the muscles of the Thenar median?
Opponens pollicis
Abductor pollicis brevis
Flexor pollicis brevis
Superficial head
(perform the functions: oppose, abduct, and flex)
What are muscles, and function of the hypothenar (ulnar)?
Opponens digiti minimi
Abductor digitit minimi
Flexor digiti minimi brevis
What do the dorsal interossei do?
Abduct the finger
What do the palmer interossei do?
Adduct the fingers
what do the lumbricals do?
Flex at the MCP joint, extend the PIP and DIP joins
Injury to obturator (L2-L4)?
Caused by pelvic surgery
Decrease thigh sensation (medial, and decrease adduction)
Injury to femoral L2-L4?
Pelvic fracture
Decrease thigh flexion and leg extension
Common peroneal L4-S2?
Trauma or compression of the lateral aspect of the leg (fibular neck fracture)
Results in foot drop (inervated and plantar flexed at rest)
Loss of sensation in the dorsum of the foot
Injury to the Tibial L4-S3 region?
Knee trauma, Baker cyst
Inability to curl toes, and loss of sensation on sole of foot
Proximal lesion: foot everted at rest with loss of inversion and plantar flexion
Injury to superior gluteal L4-S1?
Usually inatrogenci due to intramuscular injection
Trendenlenberg sign or gait
Pelvis tils because weight bearing leg cannot maintain alignement of the pelvis through hip abduction
Lesion is contralateral to the side of the hip drop (ipsilateral to the extremity on which the patient stands)
Inferior gluteal L5-S2 region?
Caused by posterior hip dislocation
Leads to difficulty climbing stairs, raising from seated position
Loss of hip extention
what does the sciatic nerve innervate?
Posterior thigh (before splitting to common peroneal and tibial nerves)
What does the pudendal nerve (S2 and S4) innervate?
The perineum (is blocked during childbrith) with ischial space as a landmark
Choose the superolateral gluteal quadrant as intramuscular injection sire to avoid nerve injury.
What are signs of lumbrosacral radiculopathy?
Parethesis and weakness in the specific regions
Often associated with disc herniation
Usually the disk protrude posterior
What is deficit if have L3-L4?
weakness of the knee extention and decfreased pateller reflex
What is deficit if have L4-L5?
Weakness of dorsiflexion, difficulty in heel walking
L5-S1 herniated disc?
Weakness of plantar flexion (difficulty in toe walking) decreased in achilles reflex
Artery associated with the long thoracic?
Lateral thoracic
Artery associated with surgical neck of humerus (axilla)
Posterior circumflex
Artery associaed with midshaft of humerous?
Nerve: Radial
Artery: Deep brachial
Artery/Nerve associated with the distal humerus and cubital fossa?
Median nerve
Brachial artery
Nerve/Artery associated with the popliteal fossa?
Tibial nerve
Popliteal artery
Nerve/artery associated with medial malleolus?
Tibial nerve
Posterior tibial artery
How does muscle contraction occur?
action potential opens up calciym gated channels (neurotransmiter release)
ligand binds to muscle cell and causes depolarization ( at muscle end plate)
Depolarization travels along the muscle cell and down the T-tubule
Ca is released from sarcoplasma
Ca binds to troponin and causes conformational change in tropomyosin (out of the myosin binding groove)
Myosin releases bound ADP and PI
Shortening of the H and I band between the Z lines
Binding of the new ATP causes the myosin head to detach
what are the differences between the type 1 and type 2 muscles?
Type 1: slow twitch (red fibers) sustained contraction
Increase after endurance training
Type 2: fast twitch (white) increase after weight and resistance training.
What is the difference between endochrondral ossification and membraneous ossification?
Endochrondial: cartilogenous model osteoblasts and osteoclasts replace with woven bone
(axial, appendicular skeleton, base of skull)
Membraneous ossification: Bones of calvarium and face (formed without cartilege)
What is function of osteoblasts?
Builds bone by secreting collagen and mineralization in akaline environment
What are osteoblasts?
Dissolves bone by secreting H+ collegen
What does parathyroid hormone do?
High levels of TH levels will cause the catabolic effects (osteitis, fibrosa cystica)
What does estrogen do?
encourgages apoptosis of the osteoclasts
Inhibits the apoptosis of osteoblasts
What is achondroplasia?
Failure of longitudinal bone growth (short limbs and large head)
Autosomal dominent with full pentrance (homozygous is lethal)
Most common cause of dwarfism
Describe the process of osteoporosis?
Cortical bone loss (even if the lab serum Ca is normal)
Can lead to vertebral compression fractures
Kyphosis, back pain, and loss of height
Can also present with fractures of the femoral neck (distal radius)
What is the cause of osteoporosis?
Increase bone absorption (due to decrease estrogen level)
Secondary to drugs (steroids and ETOH), anticonvulsants, anticoagulants, hyperparathyroidism, multiple myeloma etc
How is osteoporosis diagnoses?
Bone density with a T score < 2.5
OR with fragility fracture of the hip or vertebrae
How to treat osteoporosis?
Calcium Vitamin D during adulthood Bisphophonates Teriparatide SERMS Calcitonin weight bearing exercise
What is osteopetosis?
Failure of normal bone absorption due to defective osteoclasts
Thickened dense bone that is prone to fracture
X-ray will show a stone appeared
Can have cranial nerve impingement and palsies due to narrowed foramina
Bone marrow transplant may be curative because osteoclasts are derived from monocytes
What happens in osteomalacia and rickets?
Has defective mineralization of osteoid (adults)
Defective cartilaginous growth plates in children
What do x-rays show?
Looser zones (pseudo fractures) in osteomalasia
Will have epiphyseal widening
Metaphyseal cupping and fraying in rickets
What do children with rickets have?
Have bow legs with bead like costochondral junctions
What are the lab values for osteomalacia and rickets?
Decreased vitamin D Decreased serum Ca Increased PTH secretion Decreased PO4 Has hyperactivity of osteoblasts which cause increase in ALP
What is Paget disease of bone? (osteiti deformans)?
Local bone disorder
Have increased osteoclastic activity followed by increased osteoblastic activity.
This forms poor quality bone
What do the lab features of Paget’s disease show?
Serum Ca increased
Phosphorous and PTH level are normal
Increased ALP
Why is there heart failure in Paget’s disease?
Have increased blood flow from AV shunts
Can cause high output heart failure
Have an increase risk of osteogenic sarcoma
What are some clinical features of Paget’s disease?
Hat sizing may be difficult due to skull thickening
Can have hearing loss due to auditory foramen narrowing
What are the different stages of Paget’s disease ?
Lytic: osteoclasts
Mixed: Osteoclasts and osteoblasts
Sclerotic: osteoblasts
Quiescent: minimal osteoclasts/osteoblast activity
What is osteonecrosis?
Infarction of the bone marrow (usually very painful)
Caused by insufficiency of the femoral artery
What are the causes of osteonecrosis?
Corticosteroids ETOH Sickle Cell Trauma Bends Legg-Calve Perthes disease (idiopathic) Gaucher disease Slipped capital femoral epiphysis
What are the two types of benign bone tumors?
Osteochondroma: Most common bengin tumor
Bony exostosis
Usually males less then 25 years old
Giant Cell tumor:20-40 years old
Epiphyseal end of the long bones (usually the knee)
Locally aggressive benign tumor (soap bubble appearance on x-ray)
What are the types of malignant tumors?
Osteosarcoma: second most common after multiple myeloma
Bimodal distribution : 10-20 years, and then older then 65
Usually at metaphysis of the long bones, around the knee
2) Ewing Sarcoma: Boys less then 15 years old (usually at diaphysis of the long bones, the pelvis, scapula, ribs
Anaplastic small cell malignant tumor
What are predisposing factors for sarcoma?
Li-Farumani
Retinoblastoma
What are predisposing factors for Ewing sarcoma?
11+ 22 translocation