Miscellaneous MSK Disorders - Exam 1 Flashcards
Consider names xrays
https://www.radiologymasterclass.co.uk/tutorials/musculoskeletal/trauma/trauma_x-ray_page1
What is osteomyelitis?
osteo (bone)
myelitis (inflammation of the fatty tissues)
What are common s/s of osteomyelitis? What 2 labs should you order? What will the xray show early on?
fever associated with bone pain and tenderness. Tenderness, warmth, erythema and swelling on exam
blood cultures and ESR/CRP are commonly elevated
Early xray is usually negative
What are 3 major causes of osteomyelitis? **What is the highlighted way from lecture?These can be both _____ or _______
hematogenous
**spread from an previous infection or open wound (Jory said to think foot wounds and bed sores)
Secondary infection in the setting of vascular insufficiency or concomitant neuropathy
acute or chronic
In the hematogenous spread, where does it come from? What pt population? What gender? What part of the bone?
bacteremia and begins in the medullary canal
MC in children
MALE!!
metaphysis of long bones¹
What are risk factors for hematogenous osteomyelitis?
Complicated delivery
maternal infection at delivery
prematurity
indwelling catheters
urinary tract anomalies
sickle cell
immunodeficiency disorders
What is the MC organisms in children with hematogenous spread of osteomyelitis? What if sickle cell?
S aureus (MC)
Salmonellae (sickle cell)
Where is the MC bone location in adults for hematogenous spread of osteomyelitis? What are the 3 risk factors in adults? What are the 2 MC organisms?
In adults, often manifests in the vertebral column¹ (LS>TS>CS)
DM, IVs and indwelling urinary caths
S aureus (MC), Pseudomonas (IV drug use)
What are 4 causes of contiguous spread of osteomyelitis? When do symptoms typically start? How does it invade the bone?
open fractures/trauma, prosthetic devices, neurosurgery, septic arthritis
1 month after inoculation
Infection inoculates the bony cortex and migrates towards the medullary canal
What are the common organisms in contiguous spread osteomyelitis? MC in adults or children?
S aureus, Staph. epidermidis, Streptococcus
but really POLYmicrobial infections are more common
MC in adults
How is osteomyelitis from a secondary Infection due to Comorbid Conditions likely to occur? What type of microbes?
Often results from a chronic, progressively soft tissue infection of the foot or ankle, usually related to diabetes/diabetic ulcers and vascular insufficiency
Polymicrobial infections common, S. aureus and 𝛃-hemolytic strep
When should you probe the bone in osteomyelitis?
Probing for bone should be performed when ulcer is present
How will vertebral involvement osteomyelitis present?
slower progression 3 weeks to 3 months
Localized pain and tenderness of the involved vertebrae, pain increases with percussion over the affected area, may have fever (but not required), may have neurological symptoms
When getting blood cultures to test for osteomyelitis, must not pull from _______. How often are blood cultures positive? If negative, and suspicion is still high, what should you do next?
Cultures from overlying wounds, ulcers are NOT reliable
Blood cultures (+) in 60% of cases
bone bx
______: possible soft tissue swelling, loss of tissue planes, periarticular demineralization of bone
_______:
Periosteal thickening or elevation
Bone cortex irregularity
Osteolysis, endosteal scalloping², regional osteopenia
Early XR changes
Later XR changes greater than 2 weeks
Endosteal scalloping
periosteal reaction
osteolysis
moth sign
_______ is used to dx osteomyelitis. Which one is preferred for foot infections?
CT/MRI
MRI
What is the indication for a bone bx in osteomyelitis? Which type does NOT require it? Can you start abx before bone bx?
All patients with radiologic evidence of osteomyelitis without (+) blood cultures
Osteomyelitis by hematogenous spread doesn’t require bone bx
YES!! but often bone cultures are positive regardless of prior antibiotic therapy
What are the 2 different options for bone bx? Which one is preferred?
open** or percutaneous
percutaneous is used for vertebral osteomyelitis and must be collected through UNINFECTED soft tissue
What will the histology show of a pt with osteomyelitis?
Histology - shows necrotic bone with extensive resorption adjacent to an inflammatory exudate
What is the management plan for osteomyelitis?
consult ID and Ortho!
vancomycin + 3rd or 4th gen ceph (ceftriaxone, ceftazidime, or cefepime)
remove hardware involved
What organisms do you need to cover for in osteomyelitis? How long do you need to treat for?
MRSA and gram - organisms
Treatment for staphylococcal osteomyelitis should be at least 4 weeks in duration
Methicillin-sensitive isolates → IV cefazolin, nafcillin, or oxacillin
MRSA: vancomycin with goal trough level of 15-20mcg
If the culture shows sensitivity to S aureus, how can you tailor the tx? What abx tx specifically?
combo therapy can be effective if given for 4-6 weeks following 2 weeks of administration of appropriate IV agents
Levofloxacin or ciprofloxacin + rifampin is best
When is debridement indicated in osteomyelitis?
Infection related to open fx or surgical hardware
extensive dz involving multiple bony and soft tissue layers
concomitant joint infection
recurrent or persistent infection despite standard medical therapy
When on IV therapy for osteomyelitis, what are the monitoring requirements?
CBC and CMP weekly
ESR and CRP at the beginning and end of IV therapy and at any time symptoms worsen
IV therapy for osteomyelitis and the ESR/CRP remains elevated 2 wks after completion of abx therapy, what should you do?
consider osteomyelitis is still present
serial xrays
What is the monitoring requirements for osteomyelitis while being treated with PO therapy?
CBC, Cr and ALT at 2, 4, 8,12 weeks and every 6-12 months after initiation of PO therapy (as long as abx is continued)
serial xrays
What are the 3 osteomyelitis complications?
Bone destruction leading to pathological fractures
Chronic osteomyelitis
Impaired bone growth in children
What does chronic osteomyelitis lead to?
results in the development of sequestrum with or without a sinus tract
sequestrum
What are the 4 bone changes that occur with chronic osteomyelitis?
- Increased intramedullary pressure leads to rupture of periosteum, which forms a cloaca or sinus tract
- Periosteal blood supply interruptions leading to necrosis
- This dead bone can lead to a radiographic findings known as a sequestrum
- New bone will then begin to form in areas where the periosteum was damaged, called involucrum
Where are the 3 MC places you will see chronic osteomyelitis? Chronic infections may have ______
sternal, mandibular or foot infections
draining sinus tract
What is the management plan for chronic osteomyelitis? What are the 2 complications?
Surgical debridement
Obliteration of dead space (to stabilize the bone)
Long-term antibiotic therapy
Osteolysis and pathologic fractures
_____ is a chronic osteomyelitis sinus will undergo metaplasia and develop squamous cell carcinoma
Marjolin Ulcer
What is compartment syndrome? Where is the MC location? 2nd MC?
Compartment syndrome occurs when increased pressure within a limited space compromises the circulation and function of the muscles and nerves within that space
MC location is lower leg compartments
forearm is 2nd MC
What are the 4 lower leg compartments? What is a normal compartment pressure? Pressures up to ____ can be tolerated without damage
anterior
lateral
superficial posterior
deep posterior
normal: 10mm/Hg
up to 20mm/Hg without damage
Ischemia _____ leads to neuropathy and______ leads to myocyte death and chronic muscle contractures
> 8 hours
> 12 hours
**8 hours before IRREVERSIBLE damage occurs
**What is the MC cause of compartment syndrome?
crush injury
**What is the early and sensitive sign for compartment syndrome?
Pain out of proportion to the injury / PE findings
worse with passive stretching of the involved muscle
Pain out of proportion to the injury / PE findings
paresthesias within 30-120 minutes
tense to palpation
muscle weakness
decreased sensation
paralysis
weak pulse
What am I?
How do you dx?
compartment syndrome
measure compartment pressure!!
When measuring compartment pressure, what two places should NOT be used?
hands and feet because they are too small to get an accurate pressure reading
How do you properly perform a compartment pressure reading? What level requires decompression?
Two separate pressure readings should be obtained within 5 cm of the site
Pressure readings >45 mmHg require decompression (20-40 should be monitored)
What is the alternative approach to getting a compartment pressure?
Alternate approach → A difference between the DBP and compartment pressure <30 mm Hg = inadequate perfusion, decompression needed
Example: BP 85/52 with a compartment pressure of 28 mmHg
What are the steps in properly getting a compartment pressure reading? What is the tool called?
Steps:
Connect the manometer between the syringe and the needle
Insert needle into the compartment
Inject a few drops of saline to ensure that there are no air pockets and that the needle is not inserted into a tendon
The gauge gives the pressure reading in mmHg
Check pressures twice in each compartment (within 5 cm of fracture site)
Also check adjacent compartment pressures because pressures are highest near the injured area
Stryker Kit → saline-filled syringe, manometer, and a needle with side port
What is the management of compartment syndrome?
remove casts/dressings!!
elevate affected limb!
consult sx for surgical fasciotomy!!
What is the disposition for compartment syndrome?
ADMIT everyone!!
Those who do not meet indication for fasciotomy perform serial exams to monitor for worsening symptoms
What is the prognosis for compartment syndrome? give within 6 hours, within 12 hours and after 12 hours
Within 6 hours → most patients will have complete recovery
Within 12 hours → a little over ½ of patients will regain normal limb function
After 12 hours → < 10% will regain function
What is rhabdomyolysis associated with? What 2 lab findings are usually present? The release of _____ leads to direct ______
crush injuries!! immobility, drug toxicities and hypothermia
elevated muscle enzymes and marked electrolyte abnormalities
myoglobin, renal toxicity
**What is the urine finding very strongly associated with rhabdomyolysis? What number value?
dark, reddish-brown urine due to myoglobinuria
dark, “tea colored” urine
(+) reddish-brown color when urine myoglobin is > 100 mg/dL
What is Rhabdomyolysis? What does it cause next?
A syndrome of acute skeletal muscle cell death leading to the release of intracellular contents
Acute tubular necrosis (ATN) resulting in acute kidney injury (AKI), occurs in 30-40% of patients
Give 3 reasons why ATN results from hypovolemia in rhabdo?
Precipitation of myoglobin and uric acid crystals within renal tubules
Decreased glomerular perfusion
Nephrotoxic effect of ferrihemate (a metabolite of myoglobin)
What are the 4 highlighted etiologies from lecture?
crush injuries
deep burns
statin use
intense physical exercise
_______ is the most sensitive indicator for rhabdo. What does it reflect? Give numbers
CK level
A direct reflection of the amount of muscle injury
Levels typically 5x upper limit normal (1500 - 100,000 U/L)
When do CK levels begin to rise? When does it peak?
Levels begin to rise 2-12 hours after the onset of muscle injury
Peaks within 24 to 72 hours
**What urine finding suggests myoglobinuria?
(+) blood on dip, with negative RBC on microscopic suggests myoglobinuria
What will a CMP show of a rhabdo pt? EKG?
elevated K, BUN, Cr, AST/ALT, phosphorus, uric acid
EKG - Cardiac dysrhythmias related to hyperkalemia or hypocalcemia may occur
What is the calcium doing during the course of rhabdo? What should you be looking for in the CBC?
Hypocalcemia early in course, followed by hypercalcemia during recovery
Look for signs DIC
What is the tx for rhabdo?
IV fluids!!! early and aggressive
insert foley to measure I&O, with goal of 200-300
check urine alkalinization
monitor EKG and labs
consult nephro if super concerned about the kidneys
consult ortho/sx if concerned about compartment syndrome
What is the goal I&O in a rhabdo pt? When is urine alkalinization indicated? What is the regimen? What is the urine goal?
Goal of 200-300 mL/h UO
CK levels higher than 5000 IU/L, acidemia, dehydration, or underlying renal disease
150 mEq of sodium bicarbonate added to 1 L of 5 percent dextrose or water, administered at 200 mL/h
goal urine pH >6.5
What are the specific lab monitoring requirements for rhabdo?
CK q6h - peak CK levels > 6000 IU/L increase risk of AKI
K+ 1-2 hours after initiation of treatment
Glucose every hour if treating hyperkalemia with insulin/glucose
What is the discharge criteria in a rhabdo pt? ALL must be met
Normal renal function
Normal electrolytes
Alkaline urine
An isolated cause of the muscle injury
No uncontrolled comorbidities
What are the 3 complications of rhabdo?
Acute Kidney Injury
Compartment Syndrome
Disseminated Intravascular Coagulation due to the release of thromboplastin and other prothrombotic substances from the damaged muscle
What is fibromyalgia characterized by? **What age and gender?
A chronic condition characterized by widespread musculoskeletal pain with multiple tender points but no clear objective findings
women aged 20–55
How will fibromyalgia present? What areas are MC? Timeframe? Any joint involvement?
chronic fatigue, generalized aching pain with widespread soft tissue tenderness
neck, shoulders, low back, and hips
most days for greater than 3 months
NO! joint are unaffected
What is the dx criteria for fibromyalgia?
Widespread pain index (WPI) >7 and symptom severity (SS) scale >5 OR WPI 3-6 and SS scale >9
Symptoms have been present for at least three months
What are the 19 body regions for fibromyalgia?
What are the 3 important pt education points for fibromyalgia?
Course of disease is non-progressive
Treatment is available but not curable
Compliance and expectations regarding treatment are key to success
What are the non-pharm management options for fibromyalgia?
Cognitive behavioral therapy: focus on sleep hygiene and mood disorders
exercise
weight loss
What are the pharm management options for fibromyalgia? Which 2 medication classes should you avoid?
Muscle relaxant: cyclobenzaprine (Flexeril)
Antidepressants: amitriptyline (Elavil), duloxetine* (Cymbalta), milnacipran (Savella)*
Anticonvulsants: gabapentin (Neurontin), pregabalin (Lyrica)
Analgesic: tramadol (Ultram)
AVOID: opiates and steroids
What is the initial treatment for fibromyalgia for most patients? What if severe fatigue?
initial treatment with cyclobenzaprine or amitriptyline at bedtime
Severe fatigue: start with SNRI (Cymbalta/Savella)
Severe sleep disturbance: start with Neurontin or Lyrica
______ A condition characterized by a progressive destruction of bone and soft tissues at weight bearing joints. What is the hallmark deformity?
neurogenic arthropathy
condition is midfoot collapse, described as a “rocker-bottom” foot
What is the MC etiology of neurogenic arthropathy? What is the MC area and joints involved?
DM - most common
MC foot and ankle
MC joints
Tarsometatarsal (TMT) joint
Unilateral warmth, redness, and edema over joint region (foot/ankle)
Loss of arch, bony protrusions
pain present but at much lower severity
What am I?
40% of patients will have a _______
neurogenic arthropathy
concomitant ulceration
What kind of xray are preferred in Neurogenic Arthropathy? When should you get an MRI?
weight bearing if possible and may be normal or nonspecific in early disease
if x-ray is negative or if osteomyelitis
In a pt with neurogenic arthropathy, when repeat xrays are taken 4 months later, what will it show?
Progressive decrease of calcaneal inclination (yellow angle)
Equinus deformity at the ankle (inability to dorsiflex)
Destruction of the tarsometatarsal joint with the typical rocker-bottom deformity. (red dotted line)
What are the 4 different stages of Neurogenic Arthropathy? Give both clinical and xray findings
What is the management for stage 0-2 neurogenic arthropathy?
refer to specialist!!
Stage 0-2
Avoid weight bearing → use casting to offload the affected foot and continue until signs of inflammation resolve and improvement in radiologic findings (ranging from 3 to 25 months)
Followed by the gradual progression to normal weight bearing with prescription footwear
Charcot Restraint Orthotic Walker (CROW)
What is the management for stage 3 neurogenic arthropathy?
refer to specialist!!
Stage 3 and those who fail offloading therapy
Discuss risk/benefit of surgery
What am I?
Charcot Restraint Orthotic Walker (CROW)
What are the 2 triggers of Raynaud’s phenomenon? What is the pathophys? What part of the body is MC affected?
cold or emotional stress
Vasoconstriction leading to well-demarcated digital pallor or cyanosis followed by rapid vasodilation resulting in intense hyperemia and rubor
FINGERS, but toes, nose and ears as well
What is the difference between primary and secondary RP? Who is the MC pt population for each type?
primary: no vascular structural abnormalities
healthy females between 15 and 30 years of age
secondary: An underlying systemic condition leads to RP
male over age 40
also associated with rheumatologic conditions
secondary RP is also associated with ______
rheumatologic conditions:
Systemic sclerosis (SSc), systemic lupus erythematosus (SLE), Sjögren syndrome, or dermatomyositis
What digits are MC affected by RP?
index, middle, and ring fingers
If you see signs of sclerodactyly, calcinosis, or digital ulcers with RP, what should you be thinking?
they have signs of underlying vascular dz
so NOT primary RP
Sclerodactyly is a localized thickening and tightness of the skin of the fingers or toes
Calcinosis - calcium deposits under the skin
What should you do to confirm the dx of RP? What will it show? What should you do next?
Examine the nailfold capillaries under magnification (ophthalmoscope)
Abnormally large loops, alternating with areas without any capillaries
suggest an underlying autoimmune rheumatic disease
Order labs to look for underlying causes → individually based upon H&P
What will primary RP show under nailfold capillary microscopy?
it will be normal!! they will have normal PE and normal nailfold capillary microscopy
What is the pharm management for RP? When is pharm therapy indicated? What should you do if the pt also fails pharm therapy?
Amlodipine (Norvasc) 5-20 mg/d
Indicated if failure to control symptoms with non-pharm therapies or if evidence of digital ulcers
Refer to vascular surgery if resistant to pharmacologic therapy
How is Marfan syndrome inherited? What does it affect? **What gene specifically?
autosomal dominant
connective tissue characterized by skeletal, ocular, and cardiovascular abnormalities
Mutations in the fibrillin gene (FBN1) on chromosome 15
What eye complications are seen with Marfan Syndrome?
Ectopia lentis (displacement of the eye lens) is present in about ½ of patients
Severe myopia (nearsightedness)
Retinal detachment can occur
What heart conditions are commonly seen with Marfan Syndrome? What medication is used?
Mitral valve prolapse is seen in about 85% of patients
Aortic root dilation is common and leads to aortic regurgitation or dissection with rupture
Long-term beta blockers slows the rate of aortic dilation
Atenolol or metoprolol
What scoring system is used to dx Marfan Syndrome? Any physical limitations?
Ghent scoring system
Restriction from vigorous physical exertion protects from aortic dissection
If Marfan syndrome is left untreated, what will happen?
Untreated Marfan will result in death in the fourth or fifth decade from aortic dissection or heart failure secondary to aortic regurgitation
Life expectancy is increased with early diagnosis, lifestyle modifications, beta-adrenergic blockade, & prophylactic aortic surgery
What 3 specialities does a pt with Marfan syndrome need to follow up with ANNUALLY?
Annual ophthalmologic evaluation
Annual orthopedic consultation
cardiology annually with ECHO
