Chapter 44: Assessment of the Musculoskeletal System

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Welcome to the Deep Dive.

We're here to basically break down complex topics fast, giving you what you need.

That's the plan.

Today, it's all about musculoskeletal assessment, really foundational stuff.

Absolutely.

It underpins everything, mobility, how we feel pain, even sensory perception.

It's all connected.

So, our mission today?

Think of it as a rapid mastery guide.

We're hitting the core A &P from the source chapter, how age changes things, the risks, key assessment techniques,

and, you know, essential diagnostic and nursing strategies,

getting you up to speed quickly.

Okay, and the chapter highlights mobility and pain as priority concepts.

Right, but we can't forget sensory perception.

It's interrelated, especially when nerves get involved.

Makes sense.

In terminology, there are a few key terms we need right off the bat.

Definitely.

We'll be talking about osteopenia.

That's the decrease in bone density you see often.

In the more severe form, osteoporosis.

Exactly.

Also, kyphosis, that hunched back posture.

And we need to nail the difference between myopathy.

A muscle tissue problem.

And neuropathy.

The nerve tissue issue.

Got it.

And that critical assessment.

The neurovascular assessment.

Or, you know, the CIRC check.

That's non -negotiable.

We'll definitely circle back to that.

It sounds crucial.

Hashtag, tag, tag, the anatomy and physiology foundation.

It really is.

It checks blood flow, nerve function,

things easily compromised.

Okay, but let's start with the basics.

Bone itself.

We know shapes long like a femur, short like finger bones.

But structurally, what's going on inside?

Well, you've got the tough outer layer, the cortical bone, and inside that is the spongy cancerous bone.

And the key for nourishment is the aversion system.

It's like this intricate network of tiny canals within the dense bone.

Carrying blood vessels and nerves.

Exactly.

Keeping the tissue alive, delivering oxygen, nutrients.

It's vital.

And the cancerous tissue holds the marrow.

Red for blood cells,

but yellow marrow.

That sounds like where the risk comes in.

Oh, absolutely.

Big time risk.

Yellow marrow is basically fat cells.

Now imagine a major fracture, say a long bone.

Those fat cells can get dislodged, squeeze into tiny channels called Volkmann canals and enter the bloodstream.

Whoa.

So the bone structure itself creates this potential hazard.

Precisely.

This can lead to fat embolism syndrome or FES.

It can be life threatening.

Shows you just how vascular bone is and how an internal injury can escalate systemically fast.

So bone isn't static, is constantly being remodeled.

What drives that?

It's a cellular tug of war, really.

You have osteoblasts, the builders, forming new bone.

And osteoclasts, they're the demolition crew breaking down or resorbing old bone.

And this is balanced.

Perfectly, usually.

Up until about age 35.

After that, the resorption, the breakdown gradually starts to outpace formation.

Which explains why bone mass tends to decrease as we age.

Exactly.

And hormones are orchestrating this whole thing, especially calcium and phosphorus.

Right, they have that inverse relationship.

If one goes up, the other tends to go down.

Key relationship.

So the thyroid gland releases calcitonin when calcium levels in the blood get too high.

What does calcitonin do?

It basically tells the osteoclasts, the breakdown cells, to chill out.

It inhibits resorption, so less calcium leaves the bone.

And the flip side.

That's parathyroid hormone, PTH.

It does the opposite.

It ramps up the osteoclasts, pulling calcium out of the bone and into the blood when levels are low.

And sex hormones.

Especially for women, that seems like a major factor.

Huge factor.

Estrogens actually stimulate the osteoblasts, the bone builders.

Ah, so that's why menopause is such a critical time.

Precisely.

When estrogen levels drop significantly, bone loss accelerates.

That's a direct line to increased osteoporosis risk.

Testosterone in men also helps, promoting bone mass.

Can't forget vitamin D in this equation.

Nope, absolutely essential.

You need it to absorb calcium and phosphorus effectively from your gut.

And without enough vitamin D.

The bone gets soft.

That's osteomalacia.

Okay, moving from bone structure to movement joints.

What are the main types?

We classify them by how much they move.

Synarthoradiol are immovable, think the sutures in your skull.

Yep.

Amphiarthoradiol are slightly movable, like in the pelvis.

And the ones we deal with most often clinically.

Those are the diarthrodial or synovial joints.

Knees, elbows, shoulders,

freely movable.

And they have that synovial lining, the fluid for lubrication.

Right.

And you know those little fluid filled sacs that cushion joints, the bursae?

If they get inflamed, that's bursitis.

And if the joint itself is inflamed?

That's arthritis.

Simple as that.

And quickly on muscles, skeletal muscle is voluntary, striped and wrapped in this connective tissue called fascia.

And the big risk with inactivity.

Muscle atrophy.

Muscles waste away pretty quickly if they aren't used.

Disuse is a major enemy here.

Hashtag tag tag age, risk and health promotion.

Okay, let's connect that A &P to the aging process.

What specific changes should we expect?

Well, osteopenia, that decreased bone density, becomes much more common.

It's almost considered a normal part of aging, though it has risks.

Like fractures.

Exactly.

And you often see spinal changes, especially kyphosis, that forward curve of the upper back.

The humped back look.

Right.

Plus, years of wear and tear combined with cartilage losing its elasticity leads to osteoarthritis or OA.

And these physical changes have direct consequences for patient care, right?

Safety implications.

Absolutely.

Critical implications.

Kyphosis affect balance, decrease coordination, maybe some muscle weakness.

Recipe for falls.

A huge increase in fall risk.

So any care plan for an older adult has to include fall prevention strategies.

It's paramount.

The source material also mentioned genetic and ethnic differences.

Can you touch on that?

Yeah, it's interesting.

For instance, data shows African Americans generally have greater bone density.

Meaning lower osteoporosis rates compared to, say, Chinese Americans or Caucasians.

Correct.

And then you have genetically linked conditions like gout.

That's a type of arthritis tied to how the body processes purines.

So given all these risks, aging, genetics, lifestyle, what's the core prevention strategy?

It boils down to a few key things.

Adequate calcium and vitamin D intake is crucial, often needing supplements.

Then strengthening exercises to support the joints and muscles.

And maybe most importantly, weight -bearing activities.

Like walking.

Jogging.

Exactly.

Anything that puts safe stress on the bones.

That stress actually signals the body to maintain bone density, fighting off that age -related resorption.

Something that really jumped out during the prep was the impact of smoking.

It seems to hit the musculoskeletal system hard.

It's devastating, really.

Smoking is linked to lower bone mineral density, making fractures more likely.

It also messes with the immune system, which delays fracture healing.

It contributes to muscle atrophy.

And it accelerates cartilage breakdown, especially in the knees.

That's a lot of negative effects.

Really strong case for quitting.

No question.

And nutrition is key for healing, too.

If you don't get enough protein, vitamin

Recovery slows way down.

And obesity.

Constant excessive stress on joints, especially hips and knees.

Plus, it often limits mobility, which creates a whole other set of problems.

Hashtag tech, clinical manifestations, and focused assessment.

Alright, so a patient presents with a musculoskeletal issue.

Where do we start?

The history is vital.

Looking for clues.

Past injuries.

Even old ones.

Definitely.

Ask about trauma.

Even something from 20, 30 years ago.

It can have long -term effects.

And other health conditions matter,

too.

Like diabetes.

Big time.

Diabetes increases risk for poor healing and for osteomyelitis, which is a nasty bone infection.

Also, ask about medication history.

Long -term steroid use is notorious for causing bone loss.

What about diet?

Allergies, like dairy impacting calcium?

Exactly.

Or are they taking supplements?

Things like glucosamine or chondroitin for joint pain, which the text calls arthralgias.

It all paints a picture.

So the main things people come in complaining about were usually pain and weakness.

How do we assess pain?

Standard stuff, mostly.

Use the 0 -10 scale for intensity.

But also dig into the quality.

Is it dull?

Aching?

Burning?

Stabbing?

Location.

Radiation.

Does it move anywhere?

Is it constant or does it come and go?

Acute or chronic?

Right.

But assessing weakness requires a really crucial distinction.

This is key.

Okay, what's the difference we need to spot?

You need to figure out if it's proximal or distal.

Proximal means closer to the trunk.

Like difficulty getting up from a chair.

Or lifting arms overhead.

Exactly.

If the weakness is mainly proximal, that points strongly towards a myopathy.

A problem with the muscle tissue itself.

Okay, so proximal weakness suggests myopathy.

What about distal?

Distal weakness?

Think hands, feet, lower legs, especially if it comes with changes in sensation, like tingling or numbness.

Ah, that immediately makes you think nerves.

Bingo.

Distal weakness plus sensory changes screams neuropathy.

A nerve tissue problem.

Making that distinction early on is huge for diagnosis.

Got it.

Then the physical exam.

We start just by looking, right?

Inspection first.

Look at posture, alignment.

Are there obvious deformities?

Lordosis, that inward curve of the lower back.

Scoliosis, the S -curve.

How's their gait?

Balance?

Steadiness?

Are limbs symmetrical?

All crucial observations.

Then we move to range of motion, ROM.

Always start with active ROM, where they move themselves.

Right.

See what they can do on their own first.

If they're limited, then you might gently assess passive ROM, moving the joint for them.

And for precise measurement.

That's where the goniometer comes in.

Therapists and nurses use it to get an exact degree measurement of joint angles, like flexion and extension.

Very objective.

And remember some common patterns.

Hip pain often doesn't stay in the hip.

It can radiate to the knee or even the lower back.

Good point.

Easy to get fooled on location.

And a fusion fluid buildup in a joint is usually easiest to spot in the knee.

Okay.

Finally, muscle strength.

We need to quantify that.

How does the grading scale work?

It's usually a zero to five scale.

Five is normal strength.

They can move through the full ROM against gravity and take full resistance from you.

Okay.

Five is full power.

What about lower down?

A key one is grade three.

That means they can complete the full ROM against gravity only.

They can lift their arm up, but they can't push against any resistance at all.

So functionally quite limited already.

Very limited.

And grade zero.

That's zero muscle contraction.

Nothing happening.

Hashtag, tag, tag safety priority and diagnostics.

All right.

Let's shift gears to perhaps the most critical safety piece.

That neurovascular assessment, the CERC check.

Yes.

This is flagged as a nursing safety priority, an action alert in the source.

If there's any injury, any surgery, casting, anything involving an extremity, you must do this check regularly.

And the golden rule.

Always.

Always compare the affected limb to the unaffected one.

That's your baseline.

So what exactly are we checking below the level of the entry?

You're checking circulation and nerve function.

Feel for pulses, distal pulses.

Use a Doppler if you can't palpate them.

Aren't you pulses?

What else?

Sensation.

Can they feel light touch movement?

Can they wiggle fingers or toes skin color and temperature?

Is it pale, cool, bluish, and crucially pain?

Pain seems obvious, but why is it so critical in this check?

Because pain that seems way out of proportion to the injury or pain with passive stretch of the muscle can be an early sign of compartment syndrome.

Which is a surgical emergency can lead to limb loss.

Exactly.

So that CERC check is your early warning system.

Moving to lab tests.

What blood markers are we watching?

Calcium and phosphorus naturally given their role in bone health.

A persistent drop in serum calcium can indicate bone density loss.

Any enzymes?

Alkaline phosphatase or ALP.

It tends to go up when osteoblasts are really active like during bone healing, but also in metabolic bone diseases or bone cancer.

And if the muscle itself is damaged?

Then muscle enzymes leak into the blood.

The main one is creatine kinase, specifically the CKMM isoenzyme.

High levels indicate muscle injury.

Others like LDH, AST, aldolase might also be elevated.

Okay.

Imaging.

X -rays are the go -to for basic bone views, right?

Density, alignment, joints.

Yeah.

Standard starting point.

Patient just needs to hold still.

CT scans give more detail, especially for complex areas like the spine or joints.

Just need to check for iodine contrast allergies if using contrast.

What about when X -rays are normal, but you still suspect something like a tiny fracture?

That's where a bone scan shines.

It's a nuclear medicine test.

Great for picking up things X -rays miss like hairline fractures, early bone infections, osteomyelitis, or diffuse cancer spread in bone.

How does that work?

It requires radioactive stuff.

Yep.

A radioactive tracer, often gallium or thallium, is injected a few hours before the scan.

It collects in areas of high bone activity.

So important patient teaching.

Absolutely.

Push fluids afterwards.

Drink plenty of water to help flush a tracer out of their system.

And for soft tissues, ligaments, tendons, muscles.

MRI is the gold standard there.

It gives incredibly detailed pictures of soft tissues.

But MRIs have major safety hurdles.

Huge ones.

You must screen meticulously.

Any metal implants,

pacemaker,

old surgical clips, especially aneurysm clips,

cochlear implants,

shrapnel.

Pregnancy is usually a no -go too.

And kidney function matters for contrast.

The gadolinium contrast can be risky with poor kidney function.

And the patient has to lie perfectly still, often in a tight space, for maybe 45 minutes to an hour.

Not easy for everyone.

Lastly, direct visualization.

Arthroscopy.

Scope into the joint.

Exactly.

Usually knee or shoulder.

A surgeon inserts a small fiber optic scope to look directly at ligaments, cartilage, meniscus.

Can be diagnostic or they can do repairs at the same time.

What's needed beforehand?

Patient needs decent joint mobility to allow the soap in.

And of course, informed consent is essential.

And the top priority after the procedure.

Sound familiar?

Neurovascular checks.

Hourly, typically, right after.

That CIRC check is paramount again.

Plus standard stuff like ice, elevation for swelling.

And monitoring closely for complications, more swelling, worsening pain, signs of a claw or infection, hashtag, tag,

tag, outro.

Okay, that was a really thorough walkthrough.

What sticks with me is

how interconnected everything is.

That calcium, phosphorus, seesaw, for example.

Right.

And that critical difference in assessing weakness, proximal points to muscle.

Myopathy.

Hystal plus sensory changes points to nerves.

Neuropathy.

Getting that right seems fundamental.

And honestly, the sheer negative impact of smoking on bone and muscle health was pretty striking.

It really is.

And bringing it back to the nurse's role assessment is everything.

Understanding those typical age -related changes, like osteopenia and kyphosis, is vital for planning safe care, especially preventing falls.

And that neurovascular check.

Non -negotiable.

It's your frontline defense against losing a limb.

Master that check.

So here's a final thought for you listening.

We know bone remodeling slows down significantly after our mid -30s.

What's one small, doable weight -bearing activity you could add to your routine now?

Something sustainable to help protect your bone density for decades to come.

Something to think about for your own foundation.

A great point.

Well, thank you for joining us for this deep dive into musculoskeletal assessment fundamentals.

From the Last Minute Lecture Team, thanks so much for tuning in.

We hope this was helpful.

Get you on the next deep dive.