Comprehensive Notes: Posture, Gait, Palpation, and Clinical Reasoning

Overview of today’s goals
- Observe and discuss posture assignments
- Conduct a gait assessment on peers
- Practice palpation techniques and appropriate palpation methods
- A lot to cover; time management acknowledged

Sensitivity and Specificity

Review importance of sensitivity and specificity in diagnostic tests
Peer review logistics (Canvas)
- Access typically on a computer; mobile access can be challenging
- Auto-assign feature used; a date (e.g., 23rd at midnight) set for assignment
- Some students reported not being assigned until after submission; instructor planned to double-check
- Manual reassignment attempted after noticing gaps
Definitions and implications
- Specificity = True Negatives / (True Negatives + False Positives)
- Sensitivity = True Positives / (True Positives + False Negatives)
- “True” means the result agrees with the gold standard (e.g., x-ray confirms fracture)
Worked example: compression test for fractures
- Scenario: 10 individuals negative for fracture by gold standard; 1 positive by athletic trainer but not truly fractured
- True negatives = 9; False positives = 1
- Specificity = ext{Specificity} = rac{TN}{TN+FP} = rac{9}{9+1} = 0.9 = 90 ext{
  %}
- Explanation: 9/10 are true negatives; 1 is a false positive
Alternate (simpler) example
- Negative compression test, positive compression test example yields 50% specificity in that scenario
- Specificity here = 50 ext{
  %}
Textbook reference discussed: often ranges from about 50% to 80% depending on the test
Likelihood ratios (LR)
- Positive likelihood ratio (PLR): PLR = rac{ ext{Sensitivity}}{1 - ext{Specificity}}
- Negative likelihood ratio (NLR): NLR = rac{1 - ext{Sensitivity}}{ ext{Specificity}}
- Higher PLR is better; PLR ≥ 10 is strong evidence; lower PLR is weaker
- Example statements from class:
- For fibular fracture with a given test, PLR ≈ 2.7 (i.e., the patient with fracture is about 2.7x more likely to test positive than someone without the fracture)
- NLR ≈ 0.043 in some tests (very good for ruling out when low)
- Thompson test example: PLR ≈ 13.7; NLR ≈ 0.043
Practical note
- You are not required to calculate these in real life during exams; focus on understanding what high/low sensitivity, specificity, and likelihood ratios mean, and how to interpret them in clinical context
- AI can help locate data and compile numbers, but you must verify sources and understand the underlying concepts
Takeaway
- Understand the meaning of sensitivity, specificity, and likelihood ratios
- Use these metrics to guide interpretation of stress tests and clinical decision making

Stress Testing and Related Observations

Student engagement with real-world data
- Thompson test showed high PLR; posterior drawer test showed high specificity (99%) and high sensitivity (90%)
- A variety of tests exist with different balances of sensitivity and specificity
Class direction
- In upcoming classes, stress tests and their numbers will be discussed further; interpretation is key, not just calculation
AI caveat
- AI can aggregate data and present results, but it pulls from online sources of varying quality; always check sources

History Taking: MAP and OPQRST/OLD CART

MAP: Mechanism of Injury
- Focus on how the injury occurred and what machinery or biomechanics were involved
Acute vs Chronic and Prior History
- Distinguish acute injury events from chronic, insidious problems; note prior injuries and patterns
MAP and symptom categories
- Mechanism of injury
- Acute or chronic pain, previous injuries, current symptoms
OPQRST framework (history-taking guide)
- O = Onset
- P = Provocation (what makes it worse or better)
- Q = Quality (description of the pain/condition)
- R = Radiation (does it radiate anywhere)
- S = Severity (scale of pain or impairment)
- T = Timing (when it happens; duration; frequency)
OLD CART framework (alternative common approach)
- O = Onset
- L = Location
- D = Duration
- C = Characteristics/Quality
- A = Aggravating/Alleviating factors
- R = Radiation
- T = Time course/Timing
Goals of the history
- Generate a list of differential diagnoses (minimum three) by the end of the history
- Use questions to guide ruling in/out of different possibilities
Practical exercise reminders
- Acute vs chronic: different priorities in questioning (e.g., what worsens now vs. what has been persistent)
- MAP/OPQRST/OLD CART are tools to structure information and build a differential

Observation: The Science of Seeing Signs

Purpose of observation
- Identify signs of injury (the “science portion” of the exam)
Signs to look for (general observational checklist)
- Deformities
- Contusions (bruising)
- Ecchymosis (spelled out; ecchymosis = bruising)
- Swelling
- Redness
- Skin changes
- Lacerations
- Tenderness (though tenderness is often assessed via palpation, note observable reactions)
Start of observation
- Begins the moment the patient enters the facility
- Observe gait and posture; look for protective posturing of the injury site
Integration with history and exam
- Observation often occurs concurrently with history questions
Posture as a separate consideration
- Posture can indicate underlying musculoskeletal imbalances or compensations
Guidelines for posture/gait assessment
- Use a holistic view; consider the kinetic chain (hip, spine, shoulder, etc.)
- Look for asymmetries: pelvis levelness, scapular winging, forward shoulder posture, foot placement (supination/pronation)
Relationship to injury prevention
- Posture and gait analysis can guide corrective exercises and prevent future injuries
Suggested readings and tools
- Anatomy Trains (fascial planes; whole-body approach; posterior chain connections)
- Other textbooks with chapters on posture and gait (two recommended in class; access to free PDFs mentioned by instructor)
Ethical note on observation
- Obtain consent for posture photos or gait analysis; explain purpose; keep documentation and privacy considerations in mind

Posture: Observations and Imbalances

Why posture matters
- Forward rounded shoulders in throwers increases injury risk (shoulder, thoracic) over time
- Posture assessment is a preseason value for injury prevention
Clinical approach to posture
- Start with general posture screening; progress to detailed assessments as needed
- Posture findings inform collaboration with strength and conditioning coaches to address mobility and strength imbalances
Kinetic chain concept
- Imbalances in one area can affect distant areas through fascial and muscular chains
- Example: tight gastrocnemius or hip issues can affect distal symptoms (e.g., numbness, back pain)
The role of biomechanics and anatomy in posture
- Underlying causes may lie in the hip, T-spine mobility, or glute/hip strength; addressing these can resolve secondary complaints (e.g., shoulder pain from poor trunk mobility)
Corrective strategies
- Stretching alone is insufficient; must train antagonists to restore balance (e.g., strengthen posterior chain when addressing forward shoulder posture)
- Mobility work paired with strengthening yields better long-term outcomes
Personal practitioner insights
- Posture assessment is time-consuming but essential; some patients improve dramatically when underlying issues are found and corrected
- The value of hands-on practice and continuous learning in anatomy and biomechanics
Tools for posture assessment
- Plumb line methods, posture grids, smartphone apps (cost varies; not perfect but useful as starting point)
- Documentation with consent; use pictures to aid patient understanding and track progress
Recommended continuous learning
- Anatomy Trains book recommended for deeper understanding of fascia and chain reactions
- Encourage additional coursework in gait analysis and posture from specialized programs

Gait Analysis: Observing How We Move

Practical exercise structure
- Pair up; record one person’s gait (barefoot preferred for base assessment)
- Record a significant amount of walking back and forth to capture multiple steps
- Use mobile device to capture video; delete recordings after use to protect privacy
What to observe during gait
- Foot mechanics: pronation, overpronation, supination
- Arm swing, hip rotation, trunk alignment
- Overall symmetry and ease of movement
Role of gait analysis in diagnosis and prevention
- Gait abnormalities can indicate biomechanical issues contributing to injuries
- Gait analysis complements posture assessment and the broader exam
Tools and resources
- Gait checklists and posture checklists available in module materials
- Textbook resources and videos to illustrate normal vs. abnormal gait patterns
- Software and apps can assist, but should not replace clinician judgment
Important caveats
- Gait analysis is a complex skill; time and practice are needed to interpret patterns accurately
- Running analysis is a separate, more advanced area requiring additional training

Leg Length Discrepancy (LLD)

Types of LLD
- True leg length discrepancy (bone length difference)
- Functional or apparent discrepancy (due to soft tissue, pelvis, or pelvic tilt)"
- The topic often surfaces in chronic pain and back problems
Measurement approaches (tape measure method)
- True LLD measurement (bone length): from medial malleolus to ASIS (anterior superior iliac spine) – measures femur length and tibial alignment as a proxy for bone length
- Apparent/functional LLD measurement: from medial malleolus to umbilicus – accounts for pelvic tilt and alignment
Interpretation and limitations
- True LLD is a bone-based difference; apparent LLD can arise from pelvic tilts or soft tissue imbalances
- These measurements are not perfectly precise but are useful for screening and guiding further assessment
Practical demonstration and practice
- Students practice measuring each other’s leg length with tape measures
- Emphasis on bilateral comparison rather than absolute values; focus on symmetry
Clinical relevance and applications
- True LLD has potential to contribute to back pain and gait abnormalities
- In some cases, addressing LLD with shoe lifts or targeted therapy can relieve symptoms
Cautions and statistics
- Large true discrepancies (e.g., around 1 inch or more) are not common but can be clinically significant
- Use reliable measurement techniques and acknowledge potential measurement error
Additional notes
- Muscle length variations can also mimic LLD (e.g., tight hamstrings)
- Thorough assessment includes evaluating posture, hip alignment, and pelvis to understand the full cause

Palpation: Techniques, Ethics, and Practice

What palpation is
- The act of feeling tissues to assess structure, texture, and pathology
- Used to assess muscle, bone, tendon, fascia, skin, and neurovascular structures
Ethical and professional conduct
- Always obtain explicit permission before palpating
- Use appropriate language (avoid clinical terms that patients may misunderstand); phrase as a patient-friendly request (e.g., “Would you mind if I gently feel around this area to check.”)
- Do not palpate with lingering touch; maintain professional boundaries
- Prefer a same-sex monitor when possible; ensure someone else is present or in the room during palpation for accountability
- Keep doors open and maintain a clear, respectful exam environment
Practical palpation technique (step-by-step guidance from instructor)
- Plan your palpation region (start distally and move proximally)
- Use a single finger initially (often the index finger) to locate structures accurately
- Avoid using a flat, wide hand initially (less precise and potentially uncomfortable)
- Always palpate bilaterally for comparison
- Observe the patient’s facial expressions and responses; pain or discomfort cues guide deeper exploration
- Progress from bone to muscle to tendon (or region by region) to avoid missing structures
- When palpating near a site of injury, start away from it and work gradually toward it
- For deep tissue or specific structures, you may need firmer pressure; adjust based on patient tolerance and safety
- Consider tissue types: bone, tendon, muscle, fascia, skin, neurovascular tissue; know how each should feel
Special palpation considerations
- Identify tender points (TTP) and document them (e.g., “scaphoid tenderness”)
- Assess crepitus (a grating or popping sensation/feeling) and discuss its clinical implications
- Evaluate skin and fascia movement; learn superficial vs. deep fascia feel
- Use movement or loading to provoke tissue response (e.g., palpate a tendon during motion when it may feel different when moving)
- Palpate muscles for tone (hypertonia) vs. hypotonia and compare bilaterally
Documentation and safety
- Document findings with clear descriptors (e.g., tenderness, swelling, crepitus, asymmetry, bilaterally compared)
- Be mindful of patient comfort and safety; avoid excessive force or prolonged pressure on acutely injured sites
Practice expectations
- A dedicated palpation day is planned; students will palpate multiple body regions
- Outside-class practice and preceptor sign-offs are required; more practice improves accuracy and confidence
Practical tips from the instructor
- If you’re unsure, palpate on yourself to calibrate what a normal feel like
- Always start distal and move toward the injury; if something hurts, stop, reassess, and communicate with the patient
Limitations and ongoing learning
- Palpation is foundational but not sufficient alone; integrate with ROM, gait, and functional tests
- Seek feedback and mentorship; improper palpation can have serious professional consequences

Practice and Resources

Textbook references suggested by the instructor
- Anatomy Trains (fascial planes; holistic body approach)
- Additional posture and gait chapters in two thick textbooks (available as free PDFs via the instructor)
Practical tools and technologies
- Posture alignment grids and smartphone-based plumb line methods for quick assessment
- Gait analysis software and apps for automated feedback (useful but not a substitute for clinical judgment)
Administrative and safety notes
- Respect patient privacy when recording gait; delete recordings after use
- Ensure informed consent and comfortable patient environment during any assessment involving photos or videos
Key takeaways for exam readiness
- Be fluent in sensitivity/specificity and likelihood ratios, including interpretation of PLR and NLR values
- Understand MAP, OPQRST, and OLD CART as frameworks for thorough history taking
- Know what to observe during postural assessment and why corrective strategies should address the whole kinetic chain
- Demonstrate proper palpation technique, adherence to ethics, and systematic documentation
- Recognize that true pathology may lie proximal to the site of pain (e.g., hip/T-spine mobility affecting the shoulder or back pain from leg length discrepancies)

Quick Reference: Key Formulas and Concepts

Sensitivity and Specificity
- ext{Sensitivity} = rac{TP}{TP+FN}
- ext{Specificity} = rac{TN}{TN+FP}
Likelihood Ratios
- PLR = rac{ ext{Sensitivity}}{1 - ext{Specificity}}
- NLR = rac{1 - ext{Sensitivity}}{ ext{Specificity}}
Example interpretations
- PLR ≥ 10: strong evidence to rule in disease
- NLR ≤ 0.1: strong evidence to rule out disease
Gait and posture concepts (broad ideas)
- Gait analysis helps identify biomechanical contributors to injury
- Posture reflects muscular imbalances and kinetic chain disruptions
- Abnormal posture/gait may indicate need for mobility work and antagonist strengthening
Leg length discrepancy (LLD)
- True LLD (bone length): medial malleolus to ASIS
- Apparent LLD (functional): medial malleolus to umbilicus
- Bilateral symmetry is the practical target; discrepancies are clinically meaningful when asymmetrical
Palpation principles
- Start distally; move toward the injury; compare bilaterally
- Use gentle to deep pressure as appropriate; watch patient reactions
- Confirm tissue type by feel (bone, tendon, muscle, fascia, skin, neurovascular tissue)
- Document tenderness (TTP), swelling, crepitus, and any deformities
- Maintain patient privacy, consent, and a professional environment

If you’d like, I can reorganize these notes into a shorter quick-study sheet or expand any section with more examples or practice questions for the exam.