Muscle Group XIV Injury (Quadriceps) C&P Exam Prep

Manual Muscle Testing (MMT) - Knee Extension (Quadriceps)

What it measures: Strength of the quadriceps (Group XIV) rated on a 0-5 scale per the DBQ: 5=normal, 4=active movement against some resistance, 3=active movement against gravity only, 2=active movement with gravity eliminated, 1=palpable contraction without movement, 0=no contraction

What to expect: Examiner will ask you to straighten (extend) your knee against resistance while seated. Tested bilaterally for comparison. The examiner may also test hip flexion (sartorius contribution). Passive and active movements will be assessed.

Pain considerations: Pain during resistance testing must be verbally reported. State the exact location (e.g., anterior thigh, around the quad tendon), severity on a 0-10 scale, and how pain causes you to stop or reduce effort. Pain that limits full effort is a legitimate functional finding under DeLuca and must be documented.

Knee Range of Motion - Flexion and Extension

What it measures: Active and passive range of motion of the knee joint. Normal knee flexion is 0-140 degrees; extension is 0 degrees. Quadriceps injury may limit full active extension or cause extensor lag. Pain at end range is a critical DeLuca factor.

What to expect: Examiner will use a goniometer to measure how far you can bend (flex) and straighten (extend) the knee both actively (you move it) and passively (examiner moves it). Weight-bearing and non-weight-bearing positions may both be tested per Correia requirements. Repeated use testing (3 repetitions) should be performed.

Pain considerations: Pain on motion, including where in the arc pain begins and whether it limits the motion, must be documented by the examiner. If the examiner does not ask, volunteer this information. State: 'My knee hurts when I try to fully extend it, beginning at about X degrees, and this prevents me from completing the motion.'

Thigh Circumference / Muscle Atrophy Measurement

What it measures: Circumferential measurement of both thighs at a fixed point (e.g., 10 cm above the superior pole of the patella) to document visible or measurable quadriceps atrophy compared to the contralateral (unaffected) side.

What to expect: Examiner will use a tape measure around both thighs at the same level to compare circumference. A measurable difference (typically >1-2 cm) is documented as visible/measurable atrophy. Examiner may also visually inspect for visible wasting.

Pain considerations: Atrophy may reduce pain sensitivity in the affected area; conversely, fibrosis and scar tissue may increase focal tenderness. Report any tenderness on palpation of the quadriceps mass.

Scar Evaluation (Thigh / Quadriceps Region)

What it measures: Characteristics of scars related to the muscle injury or surgery: minimal scars, entrance/exit wound scars, ragged/depressed/adherent scars indicating wide damage, adhesion to bone, and other surgical scars. These are specific rating elements under DC 5314.

What to expect: Examiner will visually inspect and palpate any scars on the anterior thigh. They will characterize the scar type, note adherence to underlying tissues, tenderness, mobility, and size. Surgical scars from quadriceps repair or knee surgery are included.

Pain considerations: Scar tenderness, especially with movement or palpation, must be reported. Adherent scars that pull with knee flexion represent a direct functional impairment.

Functional Endurance / Repetitive Use Testing (DeLuca Factors)

What it measures: Whether repeated use of the quadriceps causes additional loss of strength, increased pain, fatigue, or incoordination - the DeLuca factors required for musculoskeletal DBQ evaluations.

What to expect: Examiner may ask you to perform repetitive knee extensions or observe you walking/climbing to assess how function changes with use. If not formally tested, you must verbally describe how your condition worsens with activity.

Pain considerations: Pain that increases with repeated use is a separate and additional impairment factor from pain at rest. Both must be documented. State: 'After walking two blocks, my thigh pain increases from a 4/10 to an 8/10 and I must stop and rest.'

10%

Slight - Injury to Group XIV (quadriceps) with minimal residuals. May have minimal scars, slight weakness or fatigue with heavy exertion, and no significant functional limitation in daily activities.

From 38 CFR: Minimal scarring with no functional impairment; slight weakness on exertion; no significant limitation of knee extension power under normal daily conditions.

20%

Moderate - Injury to Group XIV with moderate residuals. Includes definite weakness, pain on use, lowered threshold of fatigue, and possible mild atrophy. Functional limitations present with moderate exertion.

From 38 CFR: Moderate weakness with pain on use; some loss of muscle substance; lowered threshold of fatigue that limits sustained activity; possible mild atrophy with circumferential difference.

40%

Moderately Severe - Injury to Group XIV with moderately severe residuals. Significant weakness, marked atrophy, definite loss of power, impaired coordination, and functional limitations in daily living activities including difficulty climbing stairs, rising from a chair, and sustained walking.

From 38 CFR: Marked weakness with definite loss of power; substantial atrophy; impaired coordination; significant difficulty with weight-bearing activities; adherent or wide scars indicating tissue damage; possible soft/flabby muscles or impaired tonus.

50%

Severe - Injury to Group XIV with severe residuals. Near-complete loss of function of the quadriceps. Extreme weakness approaching paralysis, profound atrophy, complete loss of power for knee extension against gravity, marked incoordination, and severe functional disability. Use of assistive devices required.

From 38 CFR: Severe loss of quadriceps function with profound atrophy; Grade 2-3 strength or worse; inability to perform functional activities requiring knee extension; reliance on assistive devices; extensive scarring with adhesion to bone; possible retained foreign bodies.

Weakness and Loss of Power

How to describe it: Describe specific activities you cannot do or struggle with due to quadriceps weakness: rising from a chair without pushing off with your arms, climbing stairs one step at a time with the unaffected leg leading, inability to squat, knee buckling while walking on uneven ground.

Example: On my worst days, I cannot get up from a low chair without using both hands to push myself up, and my knee buckles on stairs so I must grip the railing with both hands and lead with my good leg every step. Walking more than half a block causes the knee to feel like it will give out.

Examiner listens for: Specific functional limitations tied to quadriceps function - knee extension strength, ability to bear weight on a bent knee, stair climbing, rising from seated. Quantified limitations (distance, repetitions before failure, time).

Avoid: Saying 'my leg is a little weak' without functional context. Never minimize: say exactly which activities you cannot do and what compensatory strategies you use (holding rails, sitting instead of squatting, avoiding stairs entirely).

Pain - Location, Character, and Triggers

How to describe it: Identify the precise location (anterior thigh, quad tendon, around the knee cap, deep in the muscle belly), character (aching, burning, sharp, throbbing, cramping), and triggers (walking, standing, going up/down stairs, prolonged sitting, weather changes). Rate pain on a 0-10 scale at rest, with normal activity, and at worst.

Example: At my worst, the front of my thigh aches constantly at a 6 out of 10 at rest and spikes to a 9 out of 10 when I try to walk more than one block or climb stairs. The pain radiates from the mid-thigh down toward my kneecap and causes me to limp noticeably. I take pain medication daily and it only partially controls it.

Examiner listens for: Specific pain descriptors, location, radiation pattern, pain at rest vs. with activity, numerical pain ratings, impact on sleep, medications used and their effectiveness, whether pain limits ROM or strength testing.

Avoid: Saying 'it hurts sometimes' - always quantify frequency (daily, every time I use stairs), severity (number scale), and functional impact (what you stopped doing because of pain).

Fatigue and Lowered Threshold of Fatigue

How to describe it: Explain that your quadriceps tire much faster than before the injury, and far faster than the unaffected leg. Describe how quickly fatigue sets in (e.g., after 5 minutes of walking, after one flight of stairs), how severe the fatigue feels, and how long recovery takes.

Example: I can walk for about five minutes before my thigh muscles feel completely exhausted and shaky. Before my injury I could walk for hours. After any exertion requiring my quadriceps, I need to sit and rest for 20-30 minutes before I can continue. By the end of a normal day, my leg is so fatigued I can barely lift it.

Examiner listens for: Onset of fatigue with minimal exertion, comparison to pre-injury or contralateral side, recovery time needed, impact on sustained work activities and daily functioning.

Avoid: Not mentioning fatigue at all because it seems less dramatic than pain. Fatigue and lowered threshold of fatigue are specific DBQ checkboxes that directly affect rating - if you experience them, describe them explicitly.

Coordination and Uncertainty of Movement

How to describe it: Describe any episodes where the knee unexpectedly gives way, buckles, or feels unstable. Note any difficulty with precise movements requiring quadriceps control (going down stairs, landing from a step, walking on uneven terrain, pivoting). Explain if you must watch your knee during movement or consciously think about each step.

Example: My knee buckles without warning when I'm walking on uneven ground or going down stairs, and I've fallen twice because of it. I have to concentrate on every step down a staircase and hold onto the railing the entire time. I cannot trust my leg to hold me when I pivot or change direction quickly.

Examiner listens for: History of falls, near-falls, or buckling; need for conscious compensation during movement; avoidance of activities requiring quick direction changes; use of assistive devices specifically to manage instability.

Avoid: Describing this as just 'weakness' - use the specific language of 'buckling,' 'giving out,' 'unpredictable,' and 'uncertainty of movement,' which correspond directly to DBQ checkboxes.

Atrophy and Physical Changes

How to describe it: Note any visible difference in the size of your affected thigh compared to the unaffected side. Describe any visible hollowing, decreased muscle bulk, or change in the contour of the anterior thigh. Mention if clothing fits differently on the two legs.

Example: My right thigh is noticeably smaller than my left - I can see the difference when I look in the mirror, and my pants fit loosely on the injured side compared to the other. The muscle above my knee looks flat and wasted where it used to be full.

Examiner listens for: Visible asymmetry, measurable circumferential difference, location of atrophy (e.g., vastus medialis most affected), whether atrophy is progressive or stable.

Avoid: Dismissing atrophy as 'just being less muscular.' If you can see or feel a difference between thighs, state it clearly and point it out to the examiner during the physical inspection.

Functional Impact on Daily Life and Work

How to describe it: Map every affected daily activity to the quadriceps: getting up from a toilet, low sofa, or car seat; climbing stairs at home or work; walking distances at work; kneeling; lifting while squatting; prolonged standing. Describe job duties you can no longer perform or perform with significant difficulty.

Example: I can no longer perform my former job duties which required climbing ladders and kneeling for extended periods. At home I cannot garden, cannot get down to floor level to play with my grandchildren, cannot carry groceries up more than three steps without stopping, and I had to install grab bars in my bathroom to get off the toilet safely.

Examiner listens for: Specific ADL limitations, occupational impact, compensatory strategies, home modifications made, and how limitations have changed over time.

Avoid: Only describing limitations during the exam setting. Describe your typical worst day at home or at work, not just how you feel sitting in the exam room after a period of rest.