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COMLEX Level 1 practice questions

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Question 1Osteopathic Principles, Practice, and Manipulative Treatment

Which set of physical findings defines somatic dysfunction in osteopathic terminology?

  1. Point tenderness, hyperreflexia, clonus, and spasticity
  2. Tissue texture change, asymmetry, restriction of motion, tenderness Correct answer.
  3. Erythema, edema, warmth, and pain in the affected region
  4. Muscle spasm, joint fixation, ligamentous laxity, and paresthesia

Explanation

Somatic dysfunction is defined by the mnemonic TART: altered tissue texture, asymmetry of bony landmarks, restriction of motion, and tenderness. These findings implicate impaired function of the somatic (body framework) system and guide treatment planning rather than implying a specific pathologic diagnosis.

Question 2Osteopathic Principles, Practice, and Manipulative Treatment

Examination of a group of thoracic vertebrae reveals sidebending to the right with rotation to the left. Which best characterizes this dysfunction?

  1. Type II dysfunction at a single segment, named for the side of rotation
  2. A non-neutral dysfunction in which rotation and sidebending occur to the same side
  3. Type I dysfunction of multiple segments, with rotation and sidebending opposite Correct answer.
  4. Type III dysfunction with motion restricted in all planes

Explanation

Fryette type I (neutral) mechanics apply to a group of vertebrae in which sidebending and rotation occur to opposite sides, and the group is named for the side of sidebending. Type II mechanics are non-neutral, single-segment dysfunctions in which sidebending and rotation occur to the same side.

Question 3Osteopathic Principles, Practice, and Manipulative Treatment

Which description is characteristic of a Fryette type II somatic dysfunction?

  1. A single segment sidebent and rotated to the same side Correct answer.
  2. A group of vertebrae held symmetrically in extension
  3. Several adjacent vertebrae sidebent to the right and rotated to the left
  4. Motion restricted in one plane only while other planes remain free

Explanation

Type II (non-neutral) dysfunction involves one segment in either flexion or extension in which sidebending and rotation occur to the same side, and it is named for the side of the restricted motion. Type I mechanics instead involve a group of segments and opposite-sided sidebending and rotation.

Question 4Osteopathic Principles, Practice, and Manipulative Treatment

Sympathetic viscerosomatic findings from the heart most commonly appear at which spinal levels?

  1. C3-C5 on the right
  2. T5-T9 on the left
  3. T10-T12 bilaterally
  4. T1-T4 on the left Correct answer.

Explanation

Cardiac sympathetic outflow arises from T1-T4, and cardiac viscerosomatic reflexes are classically described with left-sided predominance at these levels. Palpatory findings include tissue texture change, tenderness, and segmental restriction in the upper thoracic region.

Question 5Osteopathic Principles, Practice, and Manipulative Treatment

Which technique requires the patient to voluntarily contract a muscle in a controlled direction against a precisely applied counterforce?

  1. Muscle energy Correct answer.
  2. High-velocity low-amplitude
  3. Myofascial release
  4. Counterstrain

Explanation

Muscle energy technique uses the patient's own voluntary muscle contraction against a physician-applied counterforce to lengthen, strengthen, or mobilize a restricted region. It may be performed from a direct or indirect position and often uses respiratory cooperation.

Question 6Osteopathic Principles, Practice, and Manipulative Treatment

Which statement best describes counterstrain?

  1. A direct technique using a rapid, low-amplitude thrust
  2. A technique that uses rhythmic compression of the thorax
  3. An indirect technique that positions the region in greatest comfort Correct answer.
  4. A technique that applies sustained traction to the cervical spine

Explanation

Counterstrain is an indirect technique in which the affected region is carried into a position of greatest comfort that reduces the tender point, typically held for about 90 seconds. The shortened position is thought to reduce proprioceptive activity and reset the reflex arc maintaining the tender point.

Question 7Osteopathic Principles, Practice, and Manipulative Treatment

Which finding most strongly contraindicates high-velocity low-amplitude thrust to the cervical spine?

  1. Recent cervical fracture with ligamentous instability Correct answer.
  2. Mild tightness of the upper trapezius
  3. Chronic mechanical neck pain without neurologic deficit
  4. Restricted rotation at C2 on the right

Explanation

HVLA requires a velocity thrust through a restrictive barrier, so bony instability, acute fracture, or ligamentous disruption is an absolute contraindication because of the risk of catastrophic neurologic injury. Somatic dysfunction alone, even with restricted motion, is an indication rather than a contraindication.

Question 8Osteopathic Principles, Practice, and Manipulative Treatment

What is the primary physiologic goal of thoracic lymphatic pump techniques?

  1. To increase sympathetic outflow to the gastrointestinal tract
  2. To stretch the posterior thoracolumbar fascia
  3. To promote lymph flow and immune circulation Correct answer.
  4. To decrease the amplitude of the cranial rhythmic impulse

Explanation

Lymphatic pump techniques use rhythmic thoracic or abdominal compression and release to move lymph through vessels lacking intrinsic propulsion, supporting fluid balance and immune surveillance. They are used in respiratory congestion, edema, and postoperative settings.

Question 9Osteopathic Principles, Practice, and Manipulative Treatment

A group of ribs from the third through the sixth demonstrates inhalation dysfunction, with exhalation restricted. Which rib is the key rib to treat?

  1. Each rib of the group must be treated separately at its angle
  2. The third rib
  3. The sixth rib Correct answer.
  4. The fourth rib

Explanation

In inhalation dysfunction the ribs are held in inhalation and the lowest rib of the group sustains the group position, making it the key rib. In exhalation dysfunction the highest rib of the group is the key rib.

Question 10Osteopathic Principles, Practice, and Manipulative Treatment

What does a "left on left" sacral torsion describe?

  1. Bilateral sacral extension
  2. Rotation about a right oblique axis with right rotation
  3. A left anterior innominate rotation
  4. Rotation about a left oblique axis with left rotation Correct answer.

Explanation

Sacral torsion nomenclature uses two letters: the first designates the oblique axis and the second the direction of sacral rotation, so left on left means rotation about a left oblique axis with left rotation. Torsions on an oblique axis represent a failure of the sacrum to return to neutral after motion.

Question 11Osteopathic Principles, Practice, and Manipulative Treatment

Which of the following is one of the five components of the primary respiratory mechanism described by Sutherland?

  1. The rhythmic contraction of the diaphragm during quiet inspiration
  2. The cardiac cycle
  3. Sympathetic tone of the paravertebral ganglia
  4. Inherent motility of the brain and spinal cord Correct answer.

Explanation

The primary respiratory mechanism comprises inherent motility of the central nervous system, fluctuation of cerebrospinal fluid, mobility of the intracranial and intraspinal membranes, articular mobility of the cranial bones, and involuntary mobility of the sacrum between the ilia. These components are assessed together in the cranial concept.

Question 12Osteopathic Principles, Practice, and Manipulative Treatment

Compression of the fourth ventricle (CV4) is best described as which type of technique?

  1. A vault technique that exaggerates extension and slows the cranial rhythm Correct answer.
  2. A technique used primarily to increase the rate of the cranial rhythmic impulse
  3. Traction applied to the sphenobasilar synchondrosis
  4. An indirect technique that exaggerates cranial flexion

Explanation

CV4 is a vault technique that encourages sphenobasilar extension, which slows the cranial rhythmic impulse and increases its amplitude. It is used for hyperirritability, insomnia, and sympathetic overactivity.

Question 13Osteopathic Principles, Practice, and Manipulative Treatment

Preganglionic sympathetic fibers supplying the blood vessels of the lower extremities arise from which spinal levels?

  1. T10-L2 Correct answer.
  2. T1-T4
  3. S2-S4
  4. T5-T9

Explanation

All preganglionic sympathetic neurons arise from the thoracolumbar outflow T1-L2, and the lower extremity vasculature is supplied by levels T10-L2. Sacral levels supply parasympathetic outflow instead.

Question 14Osteopathic Principles, Practice, and Manipulative Treatment

Which nerves provide parasympathetic innervation to the pelvic viscera?

  1. Lumbar sympathetic chain ganglia
  2. The vagus nerve
  3. Greater splanchnic nerves
  4. Pelvic splanchnic nerves from S2-S4 Correct answer.

Explanation

The sacral parasympathetic outflow travels in the pelvic splanchnic nerves from S2-S4 to supply the descending colon, rectum, and pelvic organs. The vagus supplies thoracic and most abdominal viscera but does not reach the pelvis.

Question 15Osteopathic Principles, Practice, and Manipulative Treatment

Head's zones are best described as which of the following?

  1. Trigger points located along the paraspinal musculature
  2. Dermatomal regions of hyperalgesia associated with visceral disease Correct answer.
  3. Areas of localized subcutaneous edema overlying a diseased organ
  4. Motor points within skeletal muscle that refer pain on palpation

Explanation

Head's zones are dermatomal areas of cutaneous hyperalgesia that develop when visceral afferent input converges on the same spinal cord segment as somatic afferents. They are a form of viscerosomatic reflex used to localize visceral dysfunction.

Question 16Osteopathic Principles, Practice, and Manipulative Treatment

Which finding best distinguishes a myofascial trigger point from a counterstrain tender point?

  1. Location within the belly of a muscle
  2. A taut band that refers pain on palpation Correct answer.
  3. Reproduction of the patient's symptoms with deep palpation
  4. Presence of local tenderness at the site

Explanation

Trigger points lie within a taut band of muscle and produce characteristic referred pain, often reproducing the patient's complaint. Counterstrain tender points are small, do not refer pain, and are treated by shortening the tissue rather than by direct pressure.

Question 17Osteopathic Principles, Practice, and Manipulative Treatment

A facilitated segment is best described as which of the following?

  1. A dermatome with reduced sensation
  2. A segment with a lowered firing threshold sustained by afferent input Correct answer.
  3. A region of increased tone caused by an upper motor neuron lesion
  4. A vertebral segment fixated in extension

Explanation

Korr described the facilitated segment as a spinal cord region whose neurons fire more readily because of ongoing abnormal afferent bombardment from a somatic or visceral source. It helps explain why somatic dysfunction persists and why visceral and somatic findings travel together.

Question 18Osteopathic Principles, Practice, and Manipulative Treatment

On examination, the right anterior superior iliac spine is inferior and anterior while the right posterior superior iliac spine is superior and posterior. Which diagnosis fits these findings?

  1. Bilateral sacral flexion
  2. Right posterior innominate rotation
  3. Left anterior innominate rotation
  4. Right anterior innominate rotation Correct answer.

Explanation

In an anteriorly rotated innominate, the ASIS moves anteriorly and inferiorly while the PSIS moves superiorly and posteriorly on the involved side. The side bearing the positive landmarks determines the side of the dysfunction.

Question 19Osteopathic Principles, Practice, and Manipulative Treatment

The Still technique combines which two principles?

  1. A rapid, low-amplitude thrust delivered after positioning at the restrictive barrier
  2. An indirect position followed by a direct force through the barrier Correct answer.
  3. Sustained pressure applied to Chapman reflexes
  4. Isometric contraction of the patient's muscle against a counterforce with respiratory assistance

Explanation

The Still technique places the region indirectly into the position of ease, then applies a directed force that carries the tissues through the restrictive barrier while returning to neutral. It blends indirect positioning with a direct corrective force.

Question 20Osteopathic Principles, Practice, and Manipulative Treatment

Which mechanism is proposed to explain the therapeutic effect of counterstrain?

  1. Sustained stretch of the Golgi tendon organ
  2. Deep pressure applied to a taut band
  3. Shortening of the affected muscle to reduce spindle firing Correct answer.
  4. Cavitation of the joint space

Explanation

Counterstrain holds the dysfunctional region shortened for roughly 90 seconds, which is thought to reduce muscle spindle and proprioceptive input that maintains the reflex spasm. The tender point is then rechecked and should be markedly improved.

Question 21Osteopathic Principles, Practice, and Manipulative Treatment

Which statement best reflects Still's principle of body unity?

  1. Symptoms always arise at the site of the causative lesion
  2. Structure and function are reciprocally interrelated throughout the body Correct answer.
  3. Disease results only from invasion by external microorganisms
  4. Treatment should be directed only at the symptomatic region

Explanation

The osteopathic principle of body unity holds that the body is a single integrated unit in which structure and function are reciprocally interrelated, so dysfunction in one region can produce effects elsewhere. This principle underlies the search for remote somatic contributors to a patient's complaint.

Question 22Osteopathic Principles, Practice, and Manipulative Treatment

Ribs one through five primarily move in which pattern during respiration?

  1. Piston motion, increasing vertical diameter
  2. Bucket-handle motion, increasing transverse diameter
  3. Pump-handle motion, increasing anteroposterior diameter Correct answer.
  4. Caliper motion, increasing transverse diameter

Explanation

Upper ribs one through five rotate about a transverse axis, producing pump-handle motion that increases the anteroposterior diameter of the thorax. Ribs six through ten produce bucket-handle motion that increases the transverse diameter.

Question 23Osteopathic Principles, Practice, and Manipulative Treatment

Before performing cervical HVLA, which finding most warrants withholding manipulation?

  1. Vertigo and diplopia provoked by extension and rotation Correct answer.
  2. A history of a resolved ankle sprain
  3. Tenderness of the upper trapezius
  4. Bilateral restriction of C7 rotation

Explanation

Vertigo, diplopia, dysarthria, or nausea provoked by cervical extension and rotation suggests vertebrobasilar insufficiency, and manipulation risks posterior circulation injury. Such patients require further evaluation before any high-velocity cervical technique.

Question 24Osteopathic Principles, Practice, and Manipulative Treatment

Which structure drains lymph from the lower extremities and most of the body?

  1. Inferior vena cava
  2. Azygos vein
  3. Right lymphatic duct
  4. Thoracic duct Correct answer.

Explanation

The thoracic duct collects lymph from both lower limbs, the abdomen, and the left thorax, head, and neck, emptying at the junction of the left subclavian and internal jugular veins. Only the right upper quadrant drains via the right lymphatic duct.

Question 25Osteopathic Principles, Practice, and Manipulative Treatment

Anterior Chapman reflexes are best described as which of the following?

  1. Tender points within a muscle that refer pain to a distant site
  2. Bony exostoses palpable at the levels of vertebral dysfunction
  3. Dermatomal bands of hyperalgesia associated with a diseased viscus
  4. Small, firm, boggy nodules in deep fascia or intercostal spaces Correct answer.

Explanation

Chapman reflexes are palpable neurolymphatic points, described as small, firm, or boggy nodules in the deep fascia and intercostal spaces anteriorly and along the spine posteriorly. They are used as diagnostic markers of visceral or lymphatic congestion and are treated with articulatory or inhibitory pressure.

Question 26Osteopathic Principles, Practice, and Manipulative Treatment

A 34-year-old warehouse worker is evaluated for mid-back pain. With the patient seated and the thoracic spine held in flexion, a single vertebra is found to be rotated and sidebent to the right. Which best classifies this somatic dysfunction?

  1. Type I neutral dysfunction
  2. Type II non-neutral dysfunction Correct answer.
  3. Compensatory dysfunction
  4. Group curve dysfunction

Explanation

Fryette's second law states that when the spine is placed in a non-neutral position (flexed or extended), a single vertebral segment rotates and sidebends to the same side. Because this vertebra is a single segment, in flexion, with rotation and sidebending in the same direction, it fits the type II pattern.

Question 27Osteopathic Patient Care and Procedural Skills

A 45-year-old man with full decision-making capacity declines a recommended blood transfusion after a thorough discussion of the risks and alternatives. Which is the most appropriate next step?

  1. Administer the transfusion under emergency exception
  2. Obtain consent from his spouse instead
  3. Petition the court for a treatment order
  4. Respect the refusal and document the discussion Correct answer.

Explanation

A competent adult may refuse any medical treatment, including life-sustaining therapy, even when the refusal risks death; the physician's obligation is to confirm the patient is informed, then honor and document the choice. Surrogate consent is unnecessary while the patient has capacity, and the emergency exception applies only when the patient cannot consent.

Question 28Osteopathic Patient Care and Procedural Skills

A physician positions a dysfunctional segment at the restrictive barrier and then applies a rapid, low-amplitude force. Which technique is being described?

  1. Muscle energy technique
  2. Strain-counterstrain
  3. HVLA thrust Correct answer.
  4. Myofascial release

Explanation

A high-velocity, low-amplitude thrust is a brief, quick force delivered after the joint is carried to the restrictive barrier, often producing a release or cavitation. Muscle energy uses patient-generated contractions, counterstrain uses a position of comfort, and myofascial release uses sustained soft-tissue loading.

Question 29Osteopathic Patient Care and Procedural Skills

Which sequence correctly orders the components of a SOAP progress note?

  1. Subjective, Objective, Assessment, Plan Correct answer.
  2. Subjective, Assessment, Objective, Plan
  3. Objective, Subjective, Plan, Assessment
  4. Assessment, Subjective, Objective, Plan

Explanation

SOAP stands for Subjective (history and patient report), Objective (examination findings and data), Assessment (clinical impression or diagnosis), and Plan (management and follow-up). Following this order supports clear communication, continuity of care, and appropriate documentation.

Question 30Osteopathic Patient Care and Procedural Skills

Somatic dysfunction is best characterized as which of the following?

  1. Impaired somatic system function Correct answer.
  2. A permanent and fixed spinal deformity
  3. Referred pain from a visceral organ
  4. An inflammatory lesion of muscle fascia

Explanation

Somatic dysfunction is defined as impaired or altered function of related components of the somatic system, including skeletal, arthrodial, and myofascial structures along with their vascular, lymphatic, and neural elements. It is identified clinically by tissue texture change, asymmetry, restriction of motion, and tenderness rather than by fixed structural deformity.

Question 31Osteopathic Patient Care and Procedural Skills

A 68-year-old woman with metastatic breast cancer has a known lytic lesion at L3 and segmental dysfunction at L2-L3. Which is the most appropriate approach to this region?

  1. Perform HVLA in a non-weight-bearing position
  2. Use HVLA only after imaging is repeated
  3. Avoid HVLA at the level of the bony lesion Correct answer.
  4. Apply HVLA at the level but with reduced force

Explanation

A lytic lesion represents bony destruction, and a thrust over it risks pathologic fracture or injury, so HVLA is contraindicated at that level regardless of patient position or force. Gentle indirect or myofascial techniques may be used instead while addressing other segments normally.

Question 32Osteopathic Patient Care and Procedural Skills

A physician locates a tender point over the anterior cervical region, places the neck in a position that minimizes the tenderness, holds that position for about 90 seconds, and then slowly returns the patient to neutral. Which technique is being performed?

  1. Myofascial release
  2. Ligamentous articular strain
  3. Strain-counterstrain Correct answer.
  4. Muscle energy

Explanation

Strain-counterstrain identifies a tender point, moves the region into a position of maximal comfort so the tenderness abates, maintains that position briefly, and returns the patient passively to neutral. The proposed mechanism is normalization of aberrant muscle spindle and reflex activity associated with the dysfunctional segment.

Question 33Osteopathic Patient Care and Procedural Skills

A patient with restricted hip internal rotation is asked to externally rotate the hip against the physician's unyielding counterforce, then to relax; afterward internal rotation improves. Which mechanism best explains this change?

  1. Joint cavitation
  2. Increased joint capsule viscoelasticity
  3. Post-isometric relaxation Correct answer.
  4. Activation of the stretch reflex

Explanation

In muscle energy technique the patient performs a controlled isometric contraction against a counterforce; after the contraction the muscle relaxes and lengthens, permitting motion to a new restrictive barrier. This post-isometric relaxation is a reflex phenomenon distinct from capsular stretching or the cavitation seen with thrust techniques.

Question 34Osteopathic Patient Care and Procedural Skills

While speaking with a patient newly diagnosed with pancreatic cancer, the physician asks, "How much would you like me to tell you about the results and what they mean?" Which step of the SPIKES protocol is being addressed?

  1. Perception
  2. Empathy
  3. Invitation Correct answer.
  4. Knowledge

Explanation

The Invitation step establishes how much information the patient wants to receive, allowing the physician to tailor the amount and detail of disclosure. Perception refers to what the patient already knows and Empathy to responding to emotion, while Knowledge is the actual delivery of the news.

Question 35Osteopathic Patient Care and Procedural Skills

Which condition is a contraindication to lymphatic drainage of the lower extremity?

  1. Acute deep vein thrombosis Correct answer.
  2. Chronic venous insufficiency
  3. Chronic lymphedema of the leg
  4. Postoperative edema after knee arthroscopy

Explanation

Acute deep vein thrombosis is a contraindication because mechanical mobilization could dislodge thrombus and precipitate pulmonary embolism. Chronic venous insufficiency, postoperative edema, and chronic lymphedema are indications for lymphatic and edema-reduction techniques.

Question 36Osteopathic Patient Care and Procedural Skills

A resident realizes she administered twice the ordered dose of insulin. The attending states that because the patient is stable, the event need not be documented. Which is the most appropriate action?

  1. Report it to risk management but not the patient
  2. Follow the attending's instruction and monitor the patient
  3. Document the error only in a personal note
  4. Disclose the error to the patient and document it Correct answer.

Explanation

Ethical and patient-safety standards require that harmful or potentially harmful errors be disclosed to the patient and recorded in the medical record, along with the clinical response and monitoring plan. Institutional reporting is required as well, but it supplements rather than replaces disclosure to the patient.

Question 37Osteopathic Patient Care and Procedural Skills

A 16-year-old presents alone and requests testing for gonorrhea and chlamydia, asking that his parents not be informed. Which is the most appropriate response?

  1. Require parental consent before any testing
  2. Refuse testing until he agrees to involve a parent
  3. Test but automatically notify the parents of the results
  4. Provide confidential testing and counseling Correct answer.

Explanation

Minors may generally consent to confidential diagnosis and treatment of sexually transmitted infections without parental involvement, and confidentiality protections apply to those services. Exceptions arise when there is suspected abuse, risk of harm to self or others, or a legally reportable condition.

Question 38Osteopathic Patient Care and Procedural Skills

A 78-year-old man with mild cognitive impairment refuses a below-knee amputation for a gangrenous foot. He can state his choice, explain the risks, and give reasons consistent with his longstanding values. Which best describes his decision-making capacity?

  1. He lacks capacity because the decision is life-threatening
  2. He has capacity for this decision Correct answer.
  3. He lacks capacity because of his cognitive diagnosis
  4. Capacity must be determined by a court

Explanation

Capacity is decision-specific and functional: the patient must communicate a choice, understand the relevant information, appreciate the consequences, and reason about alternatives. A diagnosis of cognitive impairment does not by itself remove capacity, and the clinical team, not a court, determines capacity while courts address legal competence.

Question 39Osteopathic Patient Care and Procedural Skills

A patient with suspected bacterial meningitis has papilledema and a new focal neurologic deficit. Which is the most appropriate next step?

  1. Perform LP immediately to identify the organism
  2. Withhold antibiotics until CSF results are available
  3. Perform LP at the bedside with a smaller needle
  4. Empiric antibiotics, then imaging, then LP Correct answer.

Explanation

Papilledema with a focal deficit suggests raised intracranial pressure with risk of herniation, so lumbar puncture is deferred until imaging excludes a mass lesion. Because delay in treating bacterial meningitis worsens outcomes, blood cultures and empiric antibiotics, with or without dexamethasone, are given before imaging and lumbar puncture.

Question 40Osteopathic Patient Care and Procedural Skills

Which best describes anterior Chapman points?

  1. Boggy areas located over the vertebral spinous processes
  2. Palpable muscle masses at the myotendinous junction
  3. Areas of erythema along the paravertebral musculature
  4. Discrete tender nodules in the deep fascia Correct answer.

Explanation

Chapman points are small, discrete, tender nodules palpated in the deep fascia that are linked to visceral dysfunction, with anterior points on the thorax and abdomen and posterior points near the transverse processes. Viscerosomatic reflexes, by contrast, are segmental paraspinal tissue changes at the sympathetic level, and trigger points are taut bands within muscle.

Question 41Application of Knowledge for Osteopathic Medical Practice

A 34-year-old office worker has a tender, boggy region in the upper trapezius with a palpable restriction at the associated thoracic segment. Which set of findings defines the somatic dysfunction demonstrated?

  1. Tenderness, anemia, redness, and elevated temperature
  2. Tissue texture change, asymmetry, restriction, tenderness Correct answer.
  3. Tumor, atrophy, rigidity, and thrombosis of the segment
  4. Tautness, atrophy, rigidity, and tremor of the limb

Explanation

Somatic dysfunction is defined by the TART mnemonic: tissue texture change, asymmetry, restriction of motion, and tenderness. Palpatory boggy texture and segmental motion restriction are classic findings. It is a reversible, diagnosable impairment rather than a fixed structural lesion.

Question 42Application of Knowledge for Osteopathic Medical Practice

A 45-year-old man cannot wrinkle his forehead on the right, cannot close his right eye, and has drooping of the right corner of the mouth. Which lesion best explains this pattern?

  1. A lesion of the right trigeminal motor nucleus
  2. A lesion of the left hypoglossal nerve
  3. A lower motor neuron lesion of the right facial nerve Correct answer.
  4. An upper motor neuron lesion of the left facial nucleus

Explanation

The facial nerve supplies the muscles of facial expression, including the forehead. A lower motor neuron lesion produces ipsilateral weakness of the entire half of the face, forehead included. An upper motor neuron lesion spares the forehead because the upper face receives bilateral corticobulbar input.

Question 43Application of Knowledge for Osteopathic Medical Practice

Which mechanism best explains the bactericidal action of penicillin against dividing bacteria?

  1. Inhibition of bacterial DNA gyrase
  2. Inhibition of the 30S ribosomal subunit
  3. Blocking transpeptidase cross-linking of peptidoglycan Correct answer.
  4. Disruption of lipopolysaccharide transport to the outer membrane

Explanation

Beta-lactams are structural analogs of D-alanyl-D-alanine and acylate the transpeptidase enzymes, also called penicillin-binding proteins, that cross-link peptidoglycan. This weakens the cell wall and is bactericidal for actively dividing organisms.

Question 44Application of Knowledge for Osteopathic Medical Practice

A patient presents with dermatitis in sun-exposed areas, diarrhea, and progressive dementia. Deficiency of which vitamin is most likely responsible?

  1. Niacin (vitamin B3) Correct answer.
  2. Thiamine (vitamin B1)
  3. Pyridoxine (vitamin B6)
  4. Riboflavin (vitamin B2)

Explanation

Pellagra results from niacin deficiency and presents with the three Ds: dermatitis, diarrhea, and dementia. Niacin is a precursor of NAD and NADP, which are required for oxidative metabolism in rapidly turning over tissues.

Question 45Application of Knowledge for Osteopathic Medical Practice

Stimulation of which receptor increases both heart rate and myocardial contractility?

  1. Alpha-1 adrenergic receptor
  2. Beta-2 adrenergic receptor
  3. Muscarinic M2 receptor
  4. Beta-1 adrenergic receptor Correct answer.

Explanation

Beta-1 adrenergic receptors predominate in the heart, and their activation increases heart rate, contractility, and conduction velocity through Gs-mediated cyclic AMP signaling. Beta-2 receptors mediate bronchodilation and vasodilation, alpha-1 receptors mediate vasoconstriction, and M2 receptors slow the heart.

Question 46Application of Knowledge for Osteopathic Medical Practice

An increase in ventricular end-diastolic volume that produces a larger stroke volume best illustrates which principle?

  1. The Bainbridge reflex
  2. The Bowditch staircase
  3. The Frank-Starling mechanism Correct answer.
  4. The Anrep effect

Explanation

The Frank-Starling mechanism states that increasing end-diastolic volume, or preload, increases the force of contraction and stroke volume by optimizing actin-myosin overlap. The Bainbridge reflex is a heart-rate response to atrial stretch.

Question 47Application of Knowledge for Osteopathic Medical Practice

A comatose trauma patient requires immediate laparotomy to control hemorrhage, and no family member or surrogate can be reached. What is the most appropriate action?

  1. Withhold treatment until the family can be contacted
  2. Obtain written consent from any available bystander
  3. Wait for a court order appointing a guardian
  4. Proceed with treatment under the emergency exception Correct answer.

Explanation

When immediate treatment is required to prevent death or serious harm and the patient cannot consent, the emergency exception allows treatment without consent. Consent from an unrelated bystander is not valid, and delay for a court order would risk the patient's life.

Question 48Application of Knowledge for Osteopathic Medical Practice

A screening test correctly identifies 90 of 100 people who truly have a disease. This value describes which test characteristic?

  1. Specificity
  2. Positive predictive value
  3. Sensitivity Correct answer.
  4. Prevalence

Explanation

Sensitivity is the proportion of truly diseased people whom the test correctly identifies as positive, here 90 of 100. Specificity refers to correctly identifying people without disease, and predictive values depend on disease prevalence.

Question 49Application of Knowledge for Osteopathic Medical Practice

On examination the right fourth rib is held anteriorly elevated and will not descend with exhalation. How is this dysfunction best described?

  1. Posterior dysfunction of the right fourth rib
  2. Exhalation dysfunction of the right fourth rib
  3. Anterior dysfunction of the left fourth rib
  4. Inhalation dysfunction of the right fourth rib Correct answer.

Explanation

A rib held in the inhalation, or elevated, position and restricted in exhalation has an inhalation dysfunction. The dysfunction is named for the motion that is restricted, so a rib stuck down and unable to rise has an exhalation dysfunction.

Question 50Application of Knowledge for Osteopathic Medical Practice

A patient with an acute myocardial infarction has paraspinal tissue texture change and tenderness from T2 to T5 on the left. This finding is best described as which phenomenon?

  1. Somatovisceral reflex
  2. Chapman point
  3. Trigger point
  4. Viscerosomatic reflex Correct answer.

Explanation

Visceral afferents from the heart enter the spinal cord at T1-T5 and converge on the same second-order neurons as somatic afferents. This convergence produces reflex paraspinal tissue change and tenderness, termed a viscerosomatic reflex. A somatovisceral reflex travels in the opposite direction, from soma to viscera.