Chapter 9 – Musculoskeletal System Assessment

Objective Assessment

An objective MSK assessment is generally completed after the subjective assessment. If the client shows signs of clinical deterioration, such as respiratory distress, you should focus the interview portion on pertinent questions and proceed directly to the objective assessment and associated interventions. For example, a fractured rib or vertebral fracture or a fracture that has severed circulation requires urgent intervention.

Be aware of the environmental temperature in the room and the temperature of your hands. Room temperatures are not easily modified, so try to limit exposing the client’s body parts and keep them covered with their clothes or sheet/blanket until you need to assess that body part. This also follows a trauma-informed approach and maintains the client’s dignity and limits exposing them unnecessarily. If a stethoscope is needed, warm your hands and stethoscope before placing them on the client’s body.

The objective assessment of the MSK system involves a brief scan and a focus on inspection, palpation, range of motion (ROM), and manual muscle testing (MMT), and sometimes auscultation, depending on the affected area (see Table 2). Compare the body bilaterally throughout the assessment. Assess the unaffected side first for comparison with the affected side, and when a joint is affected, at the minimum, assess above and below the joint. However, it is important to note that some causes of joint pain can go beyond the joint above and joint below.

The sequential order of the objective assessment is typically based on minimizing position changes and using a cephalocaudal (head to toe) or proximal to distal approach. Although certain positions are suggested, you may need to adapt the position if a client is not able to stand or sit up. Do not conduct ROM or muscle testing if the subjective assessment and/or inspection and palpation suggest trauma to the neck or back, or a bone fracture.

Table 2: Brief overview of a MSK assessment.

 

MSK Assessment

 

Clinical Tips

 

Inspection involves systematic observation with a focus on muscles, bones, and joints. Depending on the areas inspected, this may include colour, swelling, masses, deformities, and asymmetry. Observed deformities may include subluxation (when a bone is partially dislocated within a joint) or a complete dislocation in which the articular surface of two bones are no longer aligned or connected. You also need to assess the surrounding skin condition and presence of bleeding with and whether you observe any involuntary muscle contractions (e.g., twitching, spasms).

 

Remember to compare findings bilaterally and further assess discrepancies, asking additional subjective questions when required.

Any abnormal findings noted upon inspection should be further assessed with palpation.

You should assess for the presence of muscle atrophy/wasting (loss of muscle mass and tone) in clients who have suspected musculoskeletal conditions and mobility issues. It is best evaluated by comparing the client’s muscle mass and tone to their baseline (i.e., their normal composition).

 

Palpation involves applying your hands to assess temperature, pain, masses, swelling, deformities, palpable fluid, and size and contour of muscles. You can palpate the affected area if the client notes or you observe any involuntary muscle contractions (e.g., twitching, spasms).

 

Assess the unaffected side first to compare it to the affected side.

Use the dorsal aspect of your hands to assess for temperature, because it is most sensitive to temperature changes.

For palpation, use your finger pads as they are densely innervated. Your thumb will often be used along with your fingertips when assessing joints.

A synovial joint does not normally have palpable fluid.

To learn more details about palpation techniques, review the Physical Examination Techniques: A Nurse’s Guide open educational resource.

 

Range of motion (ROM) refers to a joint’s mobility: can it stretch to its fullest extent? You should become familiar with the normal ROM of each joint. A client’s baseline also is important so that you can evaluate their progress over time.

When assessing, make note of:

  • Range of motion of the joint (full ROM or limited ROM with the specific range, and the presence of any ).
  • Quality of the movement (movements of joints should be smooth and symmetrical with no obvious misalignments).
  • Presence of pain (ask the client if they have any pain).
  • Presence of crepitus (crepitus is an abnormal grating or crunching sound or sensation felt and heard over joints at the location where bones meet. It occurs when the articular surface of bones grind together. It is different from the sounds that are made when a person cracks their fingers or joints, which are caused by the slipping of tendons/ligaments over bony surfaces. Ask the client to move their joints through a range of motion and listen. If the client has pain or a limited range of motion, you may cup your hand over the joint or grasp the joint with your fingers and thumb.).

When performing ROM exercises, encourage the client to try to perform active ROM first, meaning that they move without assistance. If they are unable, help the client perform assisted active ROM, and then move to passive ROM as needed.

  • Assisted active ROM is when you are providing some assistance to help the client with ROM.
  • Passive ROM is when a healthcare provider or equipment/machine moves the client’s joints through ROM positions for a specific joint.

With all ROM, ensure the joint is still and stabilized. When performing assisted active or passive ROM, always support the client’s joint and maintain proper body alignment throughout the movement. It is appropriate to provide light pressure to fully test the full ROM of the joint, but you should never force a joint beyond its capacity, as this could cause damage.

 

It is helpful to demonstrate the movement so that the client can mirror the motions you make. Before beginning, ensure the client’s body is aligned. As the client moves through the motions, ensure stability of the body part proximal to the joints.

Ideally, the client would perform ROM bilaterally at the same time in order to make comparisons. However, this is not possible with all joints such as the hips. Additionally, it may not be possible with clients who have mobility limitations and pain.

The guidelines for ROM angles vary across the literature. We recommend using the ROM guidelines set out by the American Academy of Orthopaedic Surgeons (1965) and Luttgens and Hamilton (1997), as they are most commonly used in practice. 

Typically, you will visually observe the angle of the joint. Note that this will be an estimate, which is an appropriate approach when doing a . If a more accurate joint angle is needed (e.g., fitting for a wheelchair), you may require a goniometer, which is a tool that measures the angle of a joint.

ROM can be affected by several factors including the person’s typical use of the joint and their age. New onset of limited ROM is a concern and is a cue that requires further investigation.

 

Manual muscle testing (MMT) evaluates the body’s capacity to innervate muscle strength. This can reveal neurologic deficits and help you evaluate their response to treatment of neuromuscular conditions. Essentially, you are evaluating the muscle strength resistance against the force of the assessor (i.e., the nurse).

The Medical Research Council (MRC) Manual Muscle Testing scale (1943) is a common tool used and accepted by healthcare providers (James, 2007). It uses a grading scale of 0–5 to measure upper and lower extremities resistance against applied pressure by the healthcare provider in various ROM exercise movements (see Table 3).

An alternative method to test muscle strength is to use a dynamometry, which is a kind of mechanical equipment. The tool can record a more precise measurement of the muscle strength. However, not all healthcare facilities have access to this equipment.

Another method to assess a client’s muscle strength is a functional test. This kind of test assesses performance during activities of daily living; examples include the 30 Seconds Sit to Stand test or the Timed Up, Go (TUG) test.

 

 

MMT can be evaluated in several ways. Check with the unit policy to see if there is a preferred approach.

The MRC tool is somewhat controversial in terms of grade breakdown, as the subjective nature of skill when performing MMT (Naqvi, 2019). You can minimize subjectivity by being consistent in how you perform these techniques.

Keep these tips in mind when performing MMT:

  • Before beginning, assess the environment. Are there any situational factors that might affect the client’s MMT performance (e.g., pain, fatigue from medications, lack of sleep, stress)?
  • Ensure the joint is stabilized/still.
  • Maintain proper body alignment of you and the client (i.e., the muscle being tested) to ensure stability and that only the selected muscles are being tested.
  • When making comparisons bilaterally, ensure your hand is positioned on the client at the same location.
  • Test one joint at a time. This will ensure consistency and stability of the specific muscle and joint being tested.
  • Use both hands when performing MMT.
  • When applying force, be aware of your own strength and your dominant side so that you apply the same force on each side. Be aware that clients have varying muscle strength and use force accordingly. When uncertain, apply force gradually to ensure safety and minimize potential injury.
  • Compare bilaterally and report findings. For example, normal findings are full resistance equal bilaterally. Alternatively, note any asymmetry in strength and decrease in resistance.
  • Note whether the client has pain. MMT puts the tissue under a higher threshold of stress and may elicit pain.

Table 3: MMT Scale (based on Medical Research Council (MRC) Manual Muscle Testing scale, 1943).

 

Grade

 

Muscle State

 

Description

 

0

 

No contraction.

 

There is no contraction or movement of the body part being tested. Thus, MMT cannot be performed.

 

1

 

Flicker or trace of contraction.

 

There is a trace of contraction or flicker of movement of the body part being tested with no gravity and no applied force. No gravity means that the body part is supported by a bed or table.

 

2

 

Active movement, with gravity eliminated.

 

The body part being tested is able to actively move through a ROM when supported on a flat surface (i.e., supported by the table or bed) with gravity eliminated and no applied force.

 

3

 

Active movement, against gravity.

 

The body part being tested is able to actively move through a ROM against gravity without support and no applied force.

Note: If client is able to perform full active ROM, then you can assume the client is already at ⅗ on the MMT as a baseline.

 

4

 

Active movement, against gravity and resistance

 

The body part being tested is able to actively move through a ROM against gravity while you apply force and they try to resist your force, and they demonstrate partial resistance.

 

5

 

Normal power

 

The body part being tested is able to actively move through a ROM against gravity while you apply force and they try to resist your force, and they demonstrate full resistance.

 

Note: For each MMT movement, document the movement and whether the movement is equal bilaterally in strength (except spine flexion and extension, where bilateral comparison is not possible) as well as if the client experiences pain. For example, a  normal finding may be reported as “full resistance equal bilaterally on all upper limb ROM with no pain.”

Contextualizing Inclusivity

When assessing the MSK, you will need to assist the client into various body positions. Try to reduce the number of changes in body position, particularly for older clients and clients with physical disabilities who may have difficulty and possibly reduced strength to change positions. If you are assessing a newborn or young child, you can ask someone (e.g., care partner, healthcare provider, parent) to help hold and reposition the client on the exam table or in their lap while you conduct the assessment.

Knowledge Bites

Synovial joints have a small amount of fluid in the cavity between the articulating joints, but this fluid should not be palpable. Palpable fluid is a joint effusion, which refers to an accumulation of excess fluid. When palpating, it feels soft and moveable, and is sometimes associated with warmth, redness, and pain. The cause of effusions varies, but can be associated with infection, inflammation, and injury. Effusions are considered in the context of other cues, the severity, and potential causes. Treatment may be as simple as rest, ice or heat, and non-steroidal anti-inflammatory medications. Depending on the cause and severity, other treatments may include antibiotics, , and surgery.

Activity: Check your Understanding

References

American Academy of Orthopaedic Surgeons. Joint Motion: Method of Measuring and Recording. Chicago: AAOS; 1965.

James. (2007). Use of the Medical Research Council Muscle Strength Grading System in the Upper Extremity. The Journal of Hand Surgery (American Ed.), 32(2), 154–156. https://doi.org/10.1016/j.jhsa.2006.11.008

Luttgens, K. & Hamilton, N. (1997). Kinesiology: Scientific Basis of Human Motion, 9th Ed., Madison, WI: Brown & Benchmark

Medical Research Council. Aids to the investigation of peripheral nerve injuries (2nd ed.), Her Majesty’s Stationery Office, London (1943)

Naqvi U. Muscle strength grading. InStatpearls [Internet] 2019 May 29. StatPearls Publishing. Available from: https://www.ncbi.nlm.nih.gov/books/NBK436008/ (last accessed 7.1.20)

Schmitt, W.H., Cuthbert, S.C. Common errors and clinical guidelines for manual muscle testing: “the arm test” and other inaccurate procedures . Chiropr Man Therap 16, 16 (2008). https://doi.org/10.1186/1746-1340-16-16