Braddom’s PM&R Fifth Edition: Comprehensive Chapter Notes (Paraphrased)

What is the Biopsychosocial Model in PM&R?

The overarching philosophy in Physical Medicine and Rehabilitation (PM&R) that emphasizes understanding health and illness as a result of the dynamic interplay among biological (e.g., disease, injury, genetics), psychological (e.g., emotions, coping mechanisms, mood, beliefs), and social (e.g., culture, family support, socioeconomic status, employment, societal attitudes, healthcare policies) factors. It posits that disability is not solely a medical problem but a complex phenomenon influenced by a person's overall context and environment, aiming for holistic and patient-centered care.

Define the International Classification of Functioning, Disability and Health (ICF).

The World Health Organization's (WHO) internationally recognized framework for classifying health and health-related states. The ICF provides a common language and standardized framework to describe human functioning and disability across various domains. It evolved from the ICIDH to better reflect the dynamic interactions among health conditions, body functions/structures, activities, participation, and environmental/personal contextual factors, moving beyond a sole focus on consequences of disease to a more positive and universal perspective of health.

Key components: Impairment, Activity Limitation, Participation Restriction, Contextual Factors (Environmental and Personal).

What is 'Impairment' according to the ICF?

According to the ICF, this refers to a problem in body function (e.g., physiological functions of body systems, including mental functions) or body structure (e.g., anatomical parts of the body such as organs, limbs, and their components). Examples include paralysis, limb absence, visual impairment, or severe depression. It represents an objective abnormality at the organ or body system level, typically diagnosed by a healthcare professional.

What is 'Activity Limitation' according to the ICF?

According to the ICF, this refers to difficulties an individual may have in executing tasks or actions, representing the performance of a task by an individual in their actual environment. It signifies a limitation in performing an activity relative to an assumed comparable population norm. This term replaces the older term 'disability' in the ICIDH framework to avoid stigma and focus on the functional challenges rather than a label.

What is 'Participation Restriction' according to the ICF?

According to the ICF, this refers to problems an individual may experience in involvement in life situations, representing the impact of a health condition on an individual's engagement in various areas of life, such as work, education, social events, or hobbies. These difficulties often arise from interactions between health conditions and contextual factors (environmental and personal). This term replaces the older term 'handicap' in the ICIDH framework.

What is the Americans with Disabilities Act (ADA)?

A landmark civil rights law in the United States prohibiting discrimination against individuals with disabilities in all areas of public life, including employment, public services (state and local government), public accommodations (privately owned businesses open to the public), transportation, and telecommunications. It mandates 'reasonable accommodations' (adjustments or modifications that enable a person with a disability to enjoy equal employment opportunities or access to services) and removal of architectural or communication barriers to ensure equal opportunity and full integration into society.

What is a Functional Capacity Evaluation (FCE)?

A comprehensive test used to objectively assess an individual's physical capabilities and tolerances related to performing work tasks. FCEs measure physical capacities such as lifting, carrying, pushing, pulling, bending, stamina, and standing tolerance, and help identify functional limitations. They are crucial for determining safe return-to-work recommendations, suitability for specific job demands, residual work capacity, and providing objective data for disability determination and rehabilitation planning.

What are Patient-Reported Outcomes (PROs)?

Measurements of health status that come directly from the patient, without interpretation by a clinician or anyone else. PROs capture the patient's unique perspective on their symptoms (e.g., pain, fatigue), functional status, health-related quality of life, and satisfaction with treatment. They are increasingly used in clinical trials, routine clinical practice, and quality reporting to ensure patient-centered care and measure outcomes that are most meaningful to patients.

What is PROMIS?

An acronym for Patient-Reported Outcomes Measurement Information System. PROMIS is a set of highly reliable, valid, and precise patient-reported measures for various domains of physical, mental, and social health (e.g., pain interference, fatigue, physical function, depression, anxiety, social participation). These measures are often computer-adaptive (meaning the questions adapt based on previous answers, reducing respondent burden while providing accurate scores), efficient, and relevant across a wide range of chronic diseases and clinical populations, used for both clinical practice and research.

What is Maximum Medical Improvement (MMI)?

A date when a patient's medical condition has plateaued, and no further significant medical improvement is expected from continued medical or rehabilitative treatment. MMI marks the point at which a patient's impairment can be considered permanent. This date is critical in workers' compensation and disability claims as it forms the basis for determining permanent impairment ratings, establishing residual work restrictions, and concluding temporary disability benefits for the current injury or illness.

What is the Impairment Combination Formula in the DBI Framework?

A system outlined in disability rating guides (e.g., AMA Guides, Diagnosis-Based Impairment (DBI) grids) used to combine two distinct impairment percentages (referred to as A and B) from related body regions or functions into a single, aggregate impairment percentage. The formula is: \text{Combined impairment} = A + B(1 - A) where A and B are the decimal equivalents of the two impairment grades (e.g., 10% becomes 0.10, 20% becomes 0.20). This formula accounts for overlapping impairments and avoids simply adding percentages, which could lead to a rating over 100%.

What are Diagnosis-Based Impairment (DBI) Grids?

Standardized grids used in impairment rating processes (e.g., for spine and limbs) to classify the severity of an impairment into five classes (0-4), with each class corresponding to a range of impairment percentages. These grids provide a consistent and objective framework for assigning a base impairment percentage based on the diagnosis and specific clinical findings related to the condition. The initial rating from the grid can then be adjusted by specific modifiers to reflect the global functional impact on the patient.

Explain the DBI Grid Modifiers (GMFH/GMPE/GMCS).

Specific adjustment factors used to modify the base impairment rating derived from Diagnosis-Based Impairment (DBI) grids. These modifiers allow for a more nuanced and individualized impairment rating based on various clinical findings, ensuring the rating accurately reflects the patient's overall condition and functional limitations:

• G: Global Functional History: Assesses the impact of the impairment on the patient's overall daily function and activities, considering their pre-injury baseline.
• M: Major Permanent Structural Pathology: Refers to objective evidence of significant and permanent structural damage (e.g., spinal instability on imaging, joint destruction).
• P: Physical Examination: Incorporates objective findings from the clinical physical examination (e.g., range of motion limitations, motor weakness, sensory deficits) that go beyond the base diagnosis.
• E: Electrodiagnostic Studies: Utilizes results from EMG/NCS providing neurophysiological evidence (e.g., denervation activity, nerve conduction abnormalities) to support or refine the impairment rating.
• C: Clinical Studies: Includes other relevant diagnostic test results (e.g., advanced imaging beyond simple X-rays, lab findings) that shed light on the extent of impairment.
• S: Symptom Magnification: Accounts for the presence of non-organic signs, inconsistent findings, or symptom amplification that may not directly correlate with objective anatomical or physiological impairment. This modifier typically lowers the rating in cases where such factors are deemed significant.

These modifiers can either increase or decrease the final impairment rating, providing flexibility within the structured DBI system.

What are the purposes and essential elements of the Physiatric History and Physical Examination (H&P)?

The formal documentation prepared by a physiatrist that compiles essential patient information to guide treatment, communicate with the rehabilitation team, justify billing, and serve as a medicolegal record. It includes elements such as the chief complaint, history of present illness (HPI), detailed functional history (e.g., pre-morbid status, current functional limitations in ADLs, IADLs, mobility), social history, past medical/surgical history, review of systems (ROS), and a comprehensive physical examination (neurological, musculoskeletal, integumentary, etc.). Its purpose is to create a 'data platform' for treatment planning and ongoing care.

What is the significance of 'Functional History' in a PM&R H&P?

A critical component of the physiatric history that captures the patient's baseline functional status before the onset of the current illness or injury (e.g., what they could do independently, their work status, hobbies) and their current functional limitations across various domains. It often includes details on mobility (bed mobility, transfers, ambulation), ADLs (self-care), and IADLs (community living tasks), providing a benchmark for rehabilitation goals and measuring progress.

What are the key considerations when assessing mobility in a PM&R H&P?

A key component of the physiatric physical examination assessing various aspects of movement and independence:

• Bed Mobility: Ability to change positions, roll, scoot, and move from supine to sitting. Important for preventing complications like skin ulcers, DVTs, and pneumonia.
• Transfers: Evaluation of safe and independent movement between different surfaces (e.g., bed to wheelchair, wheelchair to commode, car seat, shower seat). May require assistive devices or verbal/physical assistance.
• Wheelchair Mobility: Assesses independence in propulsion (manual or power), distance covered, navigating various terrains, and ability to perform maintenance tasks of the wheelchair.
• Ambulation: Evaluation of walking ability, including distance, need for assistive devices (e.g., cane, walker, crutches), frequency of rest breaks due to fatigue or symptoms, and any associated symptoms during ambulation (e.g., chest pain, dyspnea, dizziness). Gait pattern analysis is also crucial.

What are the core concepts and components of assessing cognition, mood, and mental status (MSE) in PM&R?

A comprehensive set of assessments used to evaluate a patient's cognitive, emotional, and behavioral state during the physical examination. Key components include:

• Attention: Focused, sustained, selective, alternating, divided attention.
• Orientation: Awareness of person, place, time, and situation.
• Memory: Immediate recall, recent memory, and remote memory.
• Abstract Thinking: Ability to interpret proverbs or identify similarities/differences.
• Insight: Patient's understanding of their own condition and its implications.
• Judgment: Ability to make sound decisions and understand consequences.
• Mood/Affect: Patient's predominant emotional state (mood) and observed emotional expression (affect).
• Language: Assessing for aphasia (language disorder) or dysarthria (motor speech disorder).
• Specific Screening Tools: Examples include the Glasgow Coma Scale (GCS) for objective consciousness levels, clock-drawing test (for executive function and visuospatial skills), and Mini-Cog (for screening cognitive impairment).

Outline the structure of a Neurologic Exam in PM&R.

A systematic evaluation of the nervous system during a physiatric physical exam:

• Cranial Nerves (I–XII): Assessment of sensory and motor functions of the head and neck.
• Sensory Testing: Evaluation of light touch, pain (sharp/dull), temperature, proprioception, and vibration sense, mapped to dermatomes and peripheral nerve distributions.
• Motor Exam: Assessment of muscle strength using Manual Muscle Testing (MMT) on a 0-5 scale, muscle tone (flaccidity, spasticity, rigidity), coordination (e.g., finger-to-nose, heel-to-shin), and presence of involuntary movements.
• Reflexes: Deep tendon reflexes (DTRs), superficial reflexes, and pathological reflexes (e.g., Babinski).
• Gait Assessment: Observational analysis of walking pattern, balance, and coordination.
• Cerebellar Signs: Ataxia, dysmetria, dysdiadochokinesia, nystagmus, intention tremor.
• UMN vs. LMN Patterns: Differentiating upper motor neuron (spasticity, hyperreflexia, Babinski) from lower motor neuron (flaccidity, atrophy, fasciculations, hyporeflexia) lesions.

How is the Musculoskeletal (MSK) Exam integrated and performed in PM&R?

Integration of musculoskeletal assessment within the neuro exam, focusing on joint and muscle function:

• Range of Motion (ROM): Active (AROM) and passive (PROM) assessment using goniometry to measure joint angles. Includes specific attention to end-feel concepts (soft, firm, hard, empty) indicating the characteristic tissue resistance at the end of ROM.
• Manual Muscle Testing (MMT): Grading muscle strength on a 0-5 scale (0=no contraction, 5=normal strength against full resistance). Reliability caveats include examiner variability and patient effort.
• Practical Notes: Emphasizing using contralateral comparison (comparing to the unaffected side), maintaining patient relaxation, consistent end-feel interpretation, and utilizing standard anatomical planes for accurate measurements.

Differentiate between primitive and postural reflexes in pediatric neurologic assessment.

The specific pattern of primitive reflexes (e.g., rooting, sucking, Moro, Asymmetric Tonic Neck Reflex (ATNR), Palmar Grasp) and postural reactions (e.g., head righting, body righting, protective extension, equilibrium reactions) assessed in children. Primitive reflexes are present at birth and typically integrate (disappear) within the first year, transitioning to postural reactions around 2 months of age. Persistence of primitive reflexes beyond their expected disappearance or asymmetrical reflex responses may indicate neuropathology (e.g., cerebral palsy, hemiparesis, brachial plexopathy).

Name and describe some standardized pediatric developmental and functional assessment tools.

Standardized tools used to evaluate developmental progress in children across various domains:

• Bayley Scales of Infant and Toddler Development (Bayley-4): Comprehensive assessment for children aged 1-42 months, evaluating cognitive, language (receptive/expressive), motor (gross/fine), social-emotional, and adaptive behavior. Used for diagnosis and intervention planning.
• Denver Developmental Screening Test II (DDST-II): A widely used screening tool for children from birth to 6 years, assessing gross motor, fine motor-adaptive, language, and personal-social development. It identifies children at risk for developmental delays but is not diagnostic.
• Gross Motor Function Measure (GMFM): Specifically designed to measure changes in gross motor function over time in children with cerebral palsy, but also used in other conditions.
• Manual Ability Classification System (MACS): Classifies how children with cerebral palsy typically use their hands to handle objects in daily activities.
• Quality of Upper Extremity Skills Test (QUEST): Assesses upper extremity function in children with neuromotor dysfunction.

What are some key functional and participation measures used for children in rehabilitation?

Measures adapted for children to assess their level of independence and participation:

• WeeFIM (Functional Independence Measure for Children): An adapted version of the adult FIM, specifically for children aged 6 months to 7 years (or older children with developmental ages up to 7). It measures independent performance and the level of assistance needed from caregivers in areas of self-care, sphincter control, mobility, locomotion, communication, and social cognition, often used in inpatient pediatric rehabilitation.
• Vineland Adaptive Behavior Scales (Vineland-3): Assesses adaptive behavior (communication, daily living skills, socialization, motor skills) from birth to adulthood, crucial for understanding independence in everyday activities.
• Pediatric Quality of Life Inventory (PedsQL): A modular instrument for measuring health-related quality of life in children and adolescents.
• Child Health Questionnaire (CHQ): Assesses physical and psychosocial well-being in children and adolescents, often completed by parents.

Describe the different types of Aphasia and their characteristics.

Includes a variety of acquired language disorders resulting from brain damage (e.g., stroke, traumatic brain injury, tumor). Key types include:

• Broca's Aphasia: Non-fluent/effortful speech, preserved comprehension, impaired repetition. Lesion: posterior inferior frontal gyrus (Broca's area).
• Wernicke's Aphasia: Fluent but often meaningless/paraphasic speech ('word salad'), poor comprehension, impaired repetition. Lesion: superior temporal gyrus (Wernicke's area).
• Conduction Aphasia: Fluent speech, good comprehension, severely impaired repetition. Lesion: arcuate fasciculus (connecting Broca's and Wernicke's areas).
• Global Aphasia: Severe deficits in all language modalities (comprehension, production, repetition). Lesion: extensive perisylvian region.
• Anomic Aphasia: Primary difficulty with word-finding, otherwise fluent and comprehending. Lesion: various locations.
• Transcortical Aphasias: Spared repetition, but vary in fluency/comprehension, due to lesions isolating core language areas from surrounding cortex. (e.g., Transcortical Motor, Transcortical Sensory, Mixed Transcortical).
• Crossed Aphasia: Aphasia occurring in a right-handed individual due to a right-hemisphere lesion (rare).

What is Apraxia of Speech (AOS)?

A motor speech disorder characterized by impaired programming or planning of motor movements for speech, without significant muscle weakness, paralysis, or incoordination of the muscles themselves. It primarily affects articulation and prosody, leading to inconsistent speech errors, articulatory groping/searching behaviors, difficulty initiating speech, and distorted sounds. Apraxia is a disorder of programming volitional movements, distinguishing it from dysarthria where the issue is muscle execution.

List and describe the different types of Dysarthria and their characteristics.

A neurological motor speech disorder resulting from impairment of the muscles or neural control of speech production (respiration, phonation, resonance, articulation, prosody). It is caused by lesions to the central or peripheral nervous system affecting the motor control of speech. Types correlate with specific lesion sites and distinct speech characteristics:

• Flaccid Dysarthria: Occurs due to lower motor neuron (LMN) lesions (e.g., cranial nerves, peripheral nerves, muscle disease). Characterized by breathy voice, hypernasality, imprecise articulation, audible inspiration, and often fasciculations or atrophy.
• Spastic Dysarthria: Occurs due to bilateral upper motor neuron (UMN) lesions (e.g., pseudobulbar palsy). Characterized by a strained-strangled voice, slow speech rate, hypernasality, imprecise articulation, and excessive muscle tone.
• Ataxic Dysarthria: Occurs due to cerebellar lesions. Characterized by 'drunken' or scanning speech, irregular articulatory breakdowns, prolonged phonemes, and prosodic abnormalities (e.g., excess and equal stress).
• Hypokinetic Dysarthria: Occurs due to basal ganglia lesions (e.g., Parkinson's disease). Characterized by decreased pitch and loudness (monopitch/monoloudness), rapid and short rushes of speech, imprecise articulation, and sometimes palilalia (repetition of words or phrases).
• Hyperkinetic Dysarthria: Occurs due to basal ganglia lesions with involuntary movements (e.g., Huntington's disease, dystonia, chorea, tics). Characterized by variable speech rate and loudness, sudden phonatory arrests, distorted vowels, and irregular articulatory breakdowns reflecting the involuntary movements.
• Mixed Dysarthria: A combination of two or more pure dysarthria types, often seen in conditions affecting multiple neurological systems (e.g., Amyotrophic Lateral Sclerosis (ALS) can present with mixed spastic-flaccid dysarthria; Multiple Sclerosis may have mixed spastic-ataxic dysarthria).

What is Dysphagia, and what are its stages and common signs of aspiration?

A swallowing disorder, involving difficulties moving food or liquid from the mouth to the stomach. It can occur at three stages:

• Oral Stage: Problems with food preparation (chewing) or transport from the mouth to the pharynx (e.g., poor bolus formation, premature spillage).
• Pharyngeal Stage: Difficulties with the rapid reflex involving airway protection (vocal fold closure, epiglottic inversion) and bolus propulsion through the pharynx to the esophagus (e.g., delayed swallow reflex, residue in pharyngeal pockets, reduced laryngeal elevation).
• Esophageal Stage: Issues with bolus transport from the esophagus to the stomach (e.g., strictures, motility disorders, reflux).

Key signs of aspiration (food/liquid entering the airway) include coughing during or after swallwing, wet/gurgly voice quality post-swallow, choking, or recurrent respiratory infections/pneumonia without obvious coughing.

Describe a Videofluoroscopic Swallowing Study (VFSS).

A dynamic radiographic (X-ray) assessment also known as a 'modified barium swallow study' (MBS). It provides a comprehensive, real-time view of the oral, pharyngeal, and esophageal phases of swallowing using various bolus consistencies (thin liquid, nectar thick, honey thick, puree, solid) mixed with barium. VFSS allows visualization of bolus flow, premature spillage, airway protection mechanisms (e.g., epiglottic inversion, vocal fold closure), penetration (material entering the laryngeal vestibule above the vocal folds), and aspiration (material passing below the vocal folds). It is critical for identifying the physiology of the swallow dysfunction and guiding compensatory strategies.

Describe a Fiberoptic Endoscopic Evaluation of Swallowing (FEES).

An endoscopic procedure for evaluating swallowing function. A flexible endoscope is passed transnasally to view the pharynx and larynx. FEES allows direct visualization of anatomical structures, secretion management, and changes in vocal fold mobility. Swallowing is observed 'before' and 'after' a 'whiteout' period (when the pharynx momentarily collapses around the scope during the pharyngeal swallow). It visualizes residue after swallow, and signs of penetration/aspiration (though the actual swallow itself is obscured by the whiteout). A variant, FEESST, includes sensory testing of the pharynx. FEES is portable and does not involve radiation.

What is the Rancho Los Amigos Levels of Cognitive Functioning Scale?

A commonly used, descriptive scale that categorizes the cognitive and behavioral recovery of individuals following brain injury, particularly traumatic brain injury (TBI). It consists of 10 levels, ranging from Level I (No Response – Coma) to Level X (Purposeful, Appropriate – Modified Independent). Each level describes a distinct set of cognitive and behavioral characteristics (e.g., arousal, attention, memory, problem-solving, emotional regulation, insight), guiding rehabilitation interventions, setting appropriate goals, and providing a shared language among healthcare professionals.

Explain the Hierarchy of Attention in Cognitive Rehabilitation.

A systematic framework used in cognitive rehabilitation, particularly for attention deficits after brain injury, which posits that attention functions are hierarchically organized. Rehabilitation targets these levels sequentially:

1. Focused Attention: The ability to respond discretely to specific stimuli (e.g., auditory, visual).
2. Sustained Attention (Vigilance): The ability to maintain a consistent behavioral response during continuous and repetitive activity over time.
3. Selective Attention: The ability to focus on specific stimuli while ignoring distracting or competing stimuli.
4. Alternating Attention: The ability to shift focus of attention between tasks or stimuli with different cognitive requirements.
5. Divided Attention: The ability to respond simultaneously to multiple tasks or multiple task demands (e.g., driving while talking on the phone).

What are Restorative Strategies in Rehabilitation?

Therapeutic strategies aimed at directly improving the impaired underlying physiological or cognitive function. The goal is to restore the original capacity or skill. Examples include strengthening exercises for muscle weakness, repetitive drills for attention, or 'spaced retrieval' for memory where information is recalled over increasingly longer intervals to strengthen storage and retrieval.

What are Compensatory Strategies in Rehabilitation?

Therapeutic strategies aimed at immediately managing the symptoms or improving function by bypassing or circumventing the impaired ability, without directly changing the underlying physiology or cognition. The goal is to enable functional independence despite a persistent impairment. Examples include using walking aids (canes, walkers), utilizing memory notebooks or electronic reminder systems for memory deficits, or implementing modified diets/texture changes for dysphagia.

What is Supplemental Security Income (SSI)?

A needs-based federal income supplement program funded by general tax revenues (not Social Security taxes). It provides cash benefits to aged (65 or older), blind, or disabled individuals who have limited income and resources, regardless of their work history. SSI benefits are designed to provide a minimum level of income assistance to those who cannot work or have very low income.

What is Social Security Disability Insurance (SSDI)?

A federal insurance program that provides monthly cash benefits to individuals who have worked long enough and paid Social Security taxes to be 'insured' for benefits, and who meet the Social Security Administration's (SSA) strict definition of disability. It is an earned benefit, based on an individual's earnings record and contributions to the Social Security system.

What is the Trial Work Period (TWP)?

A Social Security work incentive that allows SSDI beneficiaries to test their ability to work for up to 9 months (not necessarily consecutive, but within a 60-month window) without losing their SSDI benefits, regardless of how much they earn. This period allows beneficiaries to determine if they can sustain employment despite their disability, providing a safety net to encourage return to work.

What is Substantial Gainful Activity (SGA)?

An amount of monthly earnings that the Social Security Administration (SSA) considers to be 'substantial gainful activity.' If an SSDI or SSI beneficiary earns above the SGA level, they generally will not be considered disabled by the SSA and their benefits may be stopped (after a grace period like the Trial Work Period). The SGA level is adjusted annually and is higher for statutorily blind individuals.

What is the Extended Period of Eligibility (EPE)?

A Social Security work incentive under the SSDI program that provides a 36-month period following the completion of the Trial Work Period. During this time, SSDI benefits can be reinstated without a new application if the beneficiary's earnings fall below the Substantial Gainful Activity (SGA) level due to their disability. It offers a crucial safety net for beneficiaries attempting to return to work, allowing for fluctuations in their earning ability.

What is a Plan for Achieving Self-Support (PASS)?

A Social Security work incentive under the SSI program that allows individuals with disabilities to set aside income or resources for a specific work goal, such as education, vocational training, starting a business, or purchasing work-related equipment. The money set aside in a PASS plan is not counted as income or resources when determining SSI eligibility or payment amount. This incentive helps remove financial barriers to employment for SSI recipients.

Explain Workers' Compensation.

A state-mandated insurance program (or federal for certain employees) that provides no-fault coverage for employees who are injured or become ill as a direct result of their job. Key aspects include:

• No-fault Coverage: Benefits are paid regardless of who was at fault for the injury, typically precluding the employee from suing the employer.
• Benefits: Includes medical and rehabilitation benefits (covering all reasonable and necessary medical care for the work-related injury/illness), temporary disability payments (for lost wages during recovery), permanent disability payments (for permanent impairment), and vocational rehabilitation (to help return to work).
• Life Care Planning: Often integrated in catastrophic injury cases to project future medical and rehabilitation needs and associated costs.

What is an Independent Medical Examination (IME)?

A one-time medical examination conducted by an independent physician (one who has not previously treated the patient) at the request of an insurance company, employer, or legal entity (e.g., in workers' compensation, personal injury litigation, or disability claims).

The purpose of an IME is to provide an objective assessment of the patient's condition, address questions of causation (is the injury work-related?), medical necessity of treatment, and current functional capacity or impairment. The IME physician's role is to be an impartial expert, providing an independent opinion based on clinical findings and medical documentation.

Describe the Donabedian Model of Quality in healthcare.

A model for evaluating healthcare quality developed by Avedis Donabedian. It proposes that quality of care can be assessed by examining three interdependent components:

• Structure: The attributes of the settings in which care is delivered. This includes facilities (e.g., hospital, clinic), equipment (e.g., MRI machines, rehabilitation robotics), human resources (e.g., staff qualifications, nurse-to-patient ratios), and organizational characteristics (e.g., electronic health record systems, accreditation).
• Process: The sum of all actions that constitute healthcare delivery. This includes how care is provided (e.g., diagnosis, treatment protocols, patient education, communication, coordination of care, adherence to clinical guidelines).
• Outcome: The effects of healthcare on the health status of patients and populations. This includes clinical outcomes (e.g., mortality, morbidity, complication rates), functional outcomes (e.g., FIM scores, return-to-work rates), patient satisfaction, and quality of life.

Donabedian emphasized that good structure increases the probability of good process, and good process increases the probability of good outcome.

What is the Functional Independence Measure (FIM)?

A widely used, 18-item ordinal scale that measures an individual's level of independence in functional abilities. It assesses 13 motor tasks (self-care, sphincter control, transfers, locomotion) and 5 cognitive tasks (communication, social cognition). Each item is scored on a 7-point scale (1 = total assistance, 7 = complete independence). FIM scores are often used in inpatient rehabilitation facilities to track functional status, monitor progress during rehabilitation, and measure rehabilitation outcomes, providing a standardized way to quantify disability and burden of care.

What is the WeeFIM (Functional Independence Measure for Children)?

A modification of the Functional Independence Measure (FIM) specifically designed for children aged 6 months to 7 years, or older children with developmental ages up to 7. WeeFIM measures a child's level of independence in 18 functional tasks across six domains: self-care, sphincter control, mobility, locomotion, communication, and social cognition. Scores reflect the amount of assistance a child requires from caregivers, providing a useful measure of functional status and caregiver burden in pediatric rehabilitation.

Explain the Seddon Classification of Nerve Injury.

A classification system for nerve injuries proposed by Sir Herbert Seddon, categorizing them by severity based on the extent of structural damage and potential for recovery:

1. Neurapraxia: The mildest form. Involves a localized conduction block (demyelination) without axonal disruption. Axons remain intact, and Wallerian degeneration does not occur. Recovery is spontaneous and complete, typically within days to weeks. Motor function is affected more than sensory.
2. Axonotmesis: Involves disruption of the axon and myelin sheath, but the surrounding connective tissue sheaths (endoneurium, perineurium, epineurium) remain intact. Wallerian degeneration occurs distal to the injury site. Recovery is possible through axonal regeneration (approximately 1 mm/day), but may be incomplete due to misdirection of regenerating axons.
3. Neurotmesis: The most severe form. Involves complete transection or severe disruption of the axon and all surrounding connective tissue sheaths. Wallerian degeneration occurs. No spontaneous recovery is possible, and functional return requires surgical repair (e.g., nerve graft or direct suture) to approximate the nerve ends.

Describe the Sunderland Classification of Nerve Injury.

A more detailed classification system for nerve injuries proposed by Sir Sydney Sunderland, expanding on Seddon's classification with five grades, providing more precise prognostic implications:

1. First-Degree Injury (Neurapraxia): Equivalent to Seddon's neurapraxia. Conduction block, axon intact. Full recovery.
2. Second-Degree Injury (Axonotmesis): Axon disrupted, endoneurium intact. Equivalent to a milder form of Seddon's axonotmesis. Full or near-full functional recovery possible as the endoneurial tubes guide regenerating axons.
3. Third-Degree Injury: Axon and endoneurium disrupted, but perineurium (fasicle sheath) intact. Intra-fascicular scarring can impede regeneration, leading to incomplete or poor spontaneous recovery. Often requires careful observation and may benefit from surgical intervention.
4. Fourth-Degree Injury: Axon, endoneurium, and perineurium disrupted, but epineurium (outer nerve sheath) intact. Only the epineurium maintains continuity. No spontaneous functional recovery is expected. Requires surgical repair (e.g., fascicular repair or nerve grafting) for any chance of meaningful recovery.
5. Fifth-Degree Injury (Neurotmesis): Complete transection of the nerve, involving disruption of all connective tissue layers (axon, endoneurium, perineurium, epineurium). Equivalent to Seddon's neurotmesis. No spontaneous recovery; requires surgical repair (direct nerve suture or nerve graft).

What types of Spontaneous Activity are seen on EMG, and what do they indicate?

Abnormal spontaneous electrical activity observed on needle electromyography (EMG) in resting muscle, indicating denervation (loss of nerve supply) and/or muscle fiber instability. These potentials are not under voluntary control.

• Fibrillation Potentials: Spontaneous depolarization of single muscle fibers, appearing as small, sharp biphasic or triphasic waveforms on EMG. Typically seen 2-3 weeks post-denervation (e.g., after nerve injury or radiculopathy) as muscle fibers become hypersensitive to acetylcholine. Suggest active denervation.
• Positive Sharp Waves (PSWs): Similar to fibrillations but with a characteristic initial positive deflection followed by a slow negative wave, indicating muscle fiber irritability, often from denervated muscle. Also seen 2-3 weeks post-denervation and represent active denervation.
• Complex Repetitive Discharges (CRDs): Often seen in chronic denervation (e.g., longstanding radiculopathy) or some myopathies. They are multi-phasic, tall, serrated waveforms that fire repetitively at a constant rate, representing the spontaneous depolarization of a group of muscle fibers that have become electrically interconnected and act as a pacemaker. They reflect chronic underlying pathology rather than acute denervation.

Describe Motor Unit Action Potentials (MUAPs) on EMG.

The electrical potentials generated by muscle fibers belonging to a single motor unit when activated voluntarily during needle EMG. Analysis of MUAPs (size, duration, shape, phases, and firing rate) provides crucial information about the integrity of the motor unit, helping differentiate neurogenic (nerve-related) from myopathic (muscle-related) disorders:

• Neurogenic MUAPs: In acute denervation, early MUAPs may be normal. In chronic denervation with reinnervation, MUAPs can become large in amplitude and long in duration (indicating collateral sprouting and larger motor units).
• Myopathic MUAPs: Typically small in amplitude and short in duration, and often polyphasic (increased number of phases), reflecting loss of individual muscle fibers within the motor unit.

Explain Motor Unit Recruitment Patterns on EMG.

Refers to the process by which increasing numbers of motor units are activated by the central nervous system to generate increasing muscle force. In EMG, the pattern of MUAP activation during voluntary contraction provides diagnostic clues:

• Reduced/Decreased Recruitment (Neurogenic): In conditions with axonal loss (e.g., severe radiculopathy, peripheral neuropathy), fewer motor units are available. The remaining motor units must fire at faster rates to compensate for the lost force. On EMG, this appears as fewer motor units firing, but at a very rapid rate ('rapid firing of single units').
• Full/Interference Pattern (Normal): During maximal voluntary contraction, many different MUAPs fire at high rates, creating a dense pattern of activity that obscures individual units.
• Early/Full Recruitment with Small MUAPs (Myopathic): In muscle diseases (myopathies), individual muscle fibers within a motor unit are lost, but not the entire motor unit. To produce a given force, more motor units are activated (recruited) than normal, but the individual MUAPs are typically small in amplitude and short in duration. This looks like a 'full' or 'too many' small units firing for the amount of force generated.

What is the typical electrodiagnostic pattern for Radiculopathy?

A neurological condition resulting from compression or irritation of a spinal nerve root, often caused by a herniated disc, spinal stenosis, or spondylosis. On electrodiagnostic studies, it is characterized by:

• Needle EMG: Evidence of denervational activity (fibrillation potentials, positive sharp waves) in muscles innervated by the affected nerve root, typically seen in both paraspinal muscles at the corresponding spinal level and limb muscles distal to the root lesion. The paraspinal muscles are uniquely innervated by the posterior primary ramus, making their involvement highly specific to root pathology.
• Nerve Conduction Studies (NCS): Sensory Nerve Action Potentials (SNAPs) are typically normal because the lesion is proximal to the dorsal root ganglion (DRG), sparing the sensory neuron cell body and its peripheral axon. Motor NCS may show reduced compound muscle action potential (CMAP) amplitudes if there is significant motor axon loss, but motor conduction velocities and distal latencies are typically normal.

What is the typical electrodiagnostic pattern for Plexopathy, and how does it differ from radiculopathy?

Damage to a nerve plexus (e.g., brachial plexus in the shoulder/arm, lumbosacral plexus in the leg), which is a network of nerves formed by the anterior rami of spinal nerves. It presents with sensory and motor deficits corresponding to multiple peripheral nerves or nerve roots. On electrodiagnostic studies, it is distinct from radiculopathy because:

• Nerve Conduction Studies (NCS): Sensory Nerve Action Potentials (SNAPs) will be abnormal (reduced amplitude or absent) because the lesion is typically distal to the dorsal root ganglion (DRG) and affects the sensory axons.
• Needle EMG: Shows denervational activity in muscles supplied by the affected plexus branches. Unlike radiculopathy, paraspinal muscle EMG is typically normal unless the lesion is very proximal (preganglionic) or extends to the nerve roots themselves. The pattern of involvement often crosses multiple nerve root levels and multiple peripheral nerve distributions.

Describe the electrodiagnostic patterns of common entrapment neuropathies: Carpal Tunnel Syndrome, Ulnar Neuropathy at Elbow, Peroneal Neuropathy at Fibular Head, and Tarsal Tunnel Syndrome.

Compression or entrapment of a single peripheral nerve at a specific anatomical site, leading to focal nerve dysfunction. Electrodiagnostic studies are crucial for confirmation and localization.

• Carpal Tunnel Syndrome (CTS): Entrapment of the median nerve at the wrist (carpal tunnel). Characterized by prolonged distal motor and/or sensory latencies of the median nerve across the wrist, often with normal proximal median nerve studies. On Needle EMG, thenar muscle abnormalities (fibrillations, PSWs, chronic changes) may be seen in more severe cases.
• Ulnar Neuropathy at Elbow (UNE): Entrapment of the ulnar nerve at the elbow (cubital tunnel). Characterized by focal slowing of conduction velocity or conduction block across the elbow segment of the ulnar nerve. Mild cases may only show EMG changes (denervation) in ulnar-innervated forearm and hand muscles.
• Peroneal Neuropathy at Fibular Head: Entrapment of the common peroneal nerve as it wraps around the fibular head. Characterized by focal slowing or conduction block across the fibular head segment of the nerve, affecting muscles of dorsiflexion and eversion of the foot. Spares the short head of the biceps femoris (innervated by tibial portion of sciatic nerve before common peroneal branches).
• Tarsal Tunnel Syndrome: Entrapment of the tibial nerve (or its branches) at the ankle, beneath the flexor retinaculum. Characterized by prolonged distal motor and/or sensory latencies to the intrinsic foot muscles and plantar sensory nerves.

Define Neurapraxia.

The mildest form of nerve injury, according to Seddon's classification. It involves a temporary conduction block due to focal demyelination of the nerve axon, without disruption of the axon itself. The nerve fiber remains structurally intact, but its ability to transmit electrical impulses is temporarily impaired across the demyelinated segment. Wallerian degeneration does not occur. Clinically, it presents with sensory or motor deficits that fully recover, typically within days to weeks, once the myelin heals. On NCS, a neurapraxia might show normal nerve conduction proximally and distally to the lesion, but significant slowing or complete block across the lesion site when stimulated.

Define Axonotmesis.

A moderate form of nerve injury where the axon and myelin sheath are disrupted, but the surrounding connective tissue elements (endoneurium, perineurium, epineurium) remain intact. This disruption leads to Wallerian degeneration of the axon distal to the injury site. Because the connective tissue scaffolding is preserved, axonal regeneration can occur, guided by the intact endoneurial tubes. Recovery is possible over weeks to months (at a rate of approximately 1 mm/day), but may be incomplete depending on the extent of axon loss and potential for misdirection of regenerating axons.

Define Neurotmesis.

The most severe form of nerve injury, involving complete transection or severe disruption of the axon and all surrounding connective tissue sheaths (endoneurium, perineurium, and epineurium). Wallerian degeneration occurs distal to the injury site. Due to the complete loss of nerve continuity and structural guidance, no spontaneous functional recovery is possible. Surgical intervention (e.g., direct nerve suture, nerve graft) is required to restore continuity, but even with surgery, recovery is often incomplete and protracted.

What is the electrodiagnostic pattern for Guillain-Barré Syndrome (GBS) / Acute Inflammatory Demyelinating Polyneuropathy (AIDP)?

An acute, immune-mediated demyelinating polyneuropathy affecting the peripheral nervous system. On electrodiagnostic studies, it is characterized by:

• NCS: Primary demyelinating features (slowing of conduction velocities, prolonged distal latencies, conduction blocks, temporal dispersion) are prominent. Motor nerves are typically more affected than sensory. F-wave latencies are usually prolonged or absent early in the course due to proximal demyelination.
• Needle EMG: May be initially normal. Later, signs of acute denervation (fibrillation potentials, positive sharp waves) may appear in muscles if significant axonal damage occurs secondary to severe demyelination.

Clinically, it presents with rapidly progressive, symmetric ascending weakness, often with sensory symptoms, and can lead to respiratory failure.

What is the electrodiagnostic pattern for Chronic Inflammatory Demyelinating Polyneuropathy (CIDP)?

A chronic, acquired immune-mediated polyneuropathy characterized by demyelination and inflammation of peripheral nerves. It is the chronic counterpart to GBS. On electrodiagnostic studies, it typically shows:

• NCS: Widespread, often asymmetric, demyelinating features with prolonged distal latencies, reduced conduction velocities, partial conduction blocks (especially in non-entrapment sites), and temporal dispersion on multiple motor and sensory nerves. These findings are often more prominent and diffuse than in GBS.
• Needle EMG: May show chronic neurogenic changes (large, long-duration MUAPs) in affected muscles, indicative of ongoing demyelination, re-demyelination, and reinnervation processes. Acute denervational activity (fibrillations, PSWs) may be present during active disease flares.

What is the electrodiagnostic pattern for Myasthenia Gravis (MG)?

A rare autoimmune disorder of the neuromuscular junction characterized by fluctuating weakness of voluntary muscles, especially those of the eyes, face, and throat. It results from antibodies attacking acetylcholine receptors (AChRs) at the postsynaptic membrane.

Electrodiagnostic Pattern:

• NCS: Typically normal.
• Repetitive Nerve Stimulation (RNS): The hallmark electrodiagnostic finding is a decremental response (a decline in Compound Muscle Action Potential (CMAP) amplitude of >10%) to low-frequency (2-5 Hz) repetitive nerve stimulation, particularly after exercise, due to reduced safety factor at the neuromuscular junction. This is more prominent in proximal muscles.
• Single-Fiber Electromyography (SFEMG): The most sensitive electrodiagnostic test, showing increased jitter (variability in inter-potential interval between two muscle fibers of the same motor unit) and blocking (failure of one fiber to consistently fire). This reflects unstable neuromuscular transmission.

What is the electrodiagnostic pattern for Lambert-Eaton Myasthenic Syndrome (LEMS)?

A rare presynaptic disorder of the neuromuscular junction, also autoimmune, characterized by impaired release of acetylcholine from nerve terminals. It is often associated with small cell lung cancer.

Electrodiagnostic Pattern:

• NCS: Low baseline Compound Muscle Action Potential (CMAP) amplitudes at rest.
• Repetitive Nerve Stimulation (RNS): The hallmark finding is a dramatic incremental (facilitatory) response of CMAP amplitude (typically >100-200% increase) to high-frequency (20-50 Hz) repetitive nerve stimulation or after brief maximal voluntary contraction. This contrasts with the decrement seen in Myasthenia Gravis.
• SFEMG: May show increased jitter and blocking.

What is the electrodiagnostic pattern for Amyotrophic Lateral Sclerosis (ALS)?

A progressive neurodegenerative disease affecting both upper motor neurons (UMNs) and lower motor neurons (LMNs). It causes progressive muscle weakness, atrophy, and spasticity.

Electrodiagnostic Pattern:

• Needle EMG: Shows evidence of both acute denervation (fibrillation potentials, positive sharp waves) in multiple muscles from different root and nerve distributions, and chronic reinnervation (large amplitude, long duration, polyphasic MUAPs) in the same muscles. This coexistence of active denervation and chronic reinnervation in multiple anatomical regions (e.g., cervical, thoracic, lumbosacral, bulbar) is characteristic. Fasciculation potentials are typically widespread.
• Nerve Conduction Studies (NCS): Usually normal or near-normal, as the primary pathology is motor neuron degeneration, not demyelination or primary axonal loss in peripheral nerves. CMAP amplitudes may be reduced in severely atrophied muscles. SNAPs are normal.

What is the electrodiagnostic pattern for Muscular Dystrophies / Inflammatory Myopathies (e.g., Polymyositis, Dermatomyositis)?

A group of inherited disorders characterized by progressive muscle weakness and degeneration. The primary pathology is in the muscle fibers themselves.

Electrodiagnostic Pattern:

• Needle EMG: Characterized by typical myopathic changes:- Small amplitude, short duration, abnormally polyphasic Motor Unit Action Potentials (MUAPs) due to loss of individual muscle fibers within the motor unit.

  • Early or 'full' recruitment patterns (many small MUAPs firing even at low force levels) because the remaining muscle fibers are attempting to compensate.
  • Spontaneous activity (e.g., fibrillations, PSWs) is typically absent or minimal unless severe degeneration is present.

• Nerve Conduction Studies (NCS): Norm. CMAP amplitudes are typically normal at rest, but with severe muscle atrophy, they may be reduced. SNAPs are normal. Conduction velocities and distal latencies are normal, indicating intact peripheral nerves.

A generalized disorder affecting multiple peripheral nerves, typically symmetrical and length-dependent (affecting distal extremities more severely). Common causes include diabetes, alcoholism, uremia, and certain medications.

Electrodiagnostic Pattern:

• Nerve Conduction Studies (NCS): The pattern depends on whether it's primarily axonal or demyelinating:
  • Axonal Neuropathy: Reduced Compound Muscle Action Potential (CMAP) and Sensory Nerve Action Potential (SNAP) amplitudes, with relatively preserved conduction velocities. This indicates