CO MLO cheat sheet

Burden of proof in civil injury cases is preponderance of the evidence (more likely than not, >50%); criminal cases require beyond a reasonable doubt.

Elements of negligence: duty, breach of duty, causation (actual and proximate), and damages; the plaintiff must prove all four.

Res ipsa loquitur permits inference of negligence when the injury would not ordinarily occur absent negligence and the instrumentality was under defendant's exclusive control.

Statute of limitations sets the deadline to file suit; statute of repose bars claims after a fixed period regardless of discovery. Discovery rule may delay accrual until injury is known.

Rescue doctrine: a rescuer injured while attempting rescue may recover from the party whose negligence created the peril.

Comparative fault reduces recovery proportionally; contributory negligence (few jurisdictions) bars recovery entirely if plaintiff is at fault.

Workers' compensation is a no-fault exclusive remedy against the employer; third-party tort claims against non-employers remain available.

Medical malpractice requires expert testimony on the standard of care except where negligence is within common knowledge (e.g., retained surgical instrument).

Informed consent requires disclosure of material risks, benefits, and alternatives; causation requires proof a reasonable patient would have declined.

Bone healing phases: inflammation (days), soft callus (weeks), hard callus (months), remodeling (months to years); remodeling follows Wolff's law along stress lines.

Tension-band plating works on the tension side of a bone; compression plating neutralizes bending and shear on the compression side.

Anterior cruciate ligament resists anterior tibial translation and internal rotation; posterior cruciate ligament resists posterior translation, strongest in the knee.

Rotator cuff: supraspinatus initiates abduction (0-15 degrees), deltoid powers 15-90 degrees; scapulohumeral rhythm is roughly 2:1.

Carpal tunnel contains the median nerve and nine flexor tendons; the ulnar nerve passes through Guyon's canal.

Compartment syndrome: elevated intracompartmental pressure compromises capillary perfusion; pressure within 30 mmHg of diastolic pressure is a classic threshold.

Whiplash injury involves flexion-extension of the cervical spine; the facet joints and capsular ligaments are common pain generators.

Fracture classification by mechanism: tension (transverse), compression (shortening), shear (oblique/spiral), bending (butterfly), torsion (spiral).

Plain radiographs are first-line for suspected fracture; sensitivity for occult fractures (e.g., scaphoid, hip) is limited, so MRI or CT may be needed.

CT is superior for cortical bone detail and complex fractures; MRI is superior for soft tissue, marrow edema, and occult fractures.

Bone marrow edema on MRI is nonspecific; it can reflect acute injury, stress reaction, infection, or tumor, and must be correlated clinically.

Degenerative changes (disc desiccation, osteophytes, facet arthropathy) are common in asymptomatic adults and do not by themselves prove injury.

Stress fractures show earliest on MRI (marrow edema), later on radiographs (periosteal reaction, sclerotic line).

Ultrasound is operator-dependent; it is useful for tendon, ligament, and effusion assessment but less reliable for bone.

Electrodiagnostic studies (EMG/NCS) localize nerve injury and distinguish axonal from demyelinating lesions; timing affects sensitivity.

Objective documentation should record mechanism, examination findings, imaging interpretation, and functional deficits rather than subjective pain ratings alone.

Causation requires both medical causation (did the event cause the condition?) and legal causation (is the defendant legally responsible?).

The eggshell plaintiff rule: a defendant takes the plaintiff as found; pre-existing vulnerability does not reduce liability for the full aggravation.

Aggravation vs. acceleration vs. precipitation: aggravation worsens an existing condition; acceleration hastens onset; precipitation triggers symptoms in a latent condition.

Apportionment separates disability attributable to the injury from that due to pre-existing or unrelated conditions; it requires a reliable baseline.

Differential diagnosis method: consider all plausible causes, then exclude by history, examination, imaging, and temporal relationship.

Temporal proximity supports but does not prove causation; a latent degenerative condition may become symptomatic without trauma.

The substantial factor test asks whether the injury was a substantial factor in producing the harm, not the sole factor.

Document pre-existing baseline function (work status, prior imaging, prior symptoms) to support or rebut apportionment claims.

The AMA Guides to the Evaluation of Permanent Impairment provides standardized impairment ratings; editions differ and jurisdiction specifies which edition applies.

Impairment is a loss of function at the organ level; disability is the effect of impairment on activities of daily living and work.

The Guides use the diagnosis-based, range-of-motion, and neurologic methods depending on the body system and edition.

Whole-person impairment converts regional impairment using the whole-person conversion factor for the body part.

Range-of-motion measurements require valid, reproducible technique; inconsistent or non-organic findings may invalidate ratings.

The Guides caution that impairment ratings are not direct measures of disability or work capacity.

Maximum medical improvement (MMI) is the point at which further recovery is not expected; impairment is rated at MMI.

Apportionment under the Guides requires identifying the impairment attributable to each condition and combining per the Guides' rules.

An independent medical examination (IME) is a records review and examination by a physician not treating the patient, typically requested by an insurer or court.

The examiner must disclose any prior relationship with the parties and any potential bias; independence is a legal and ethical requirement.

The Daubert standard (federal) and Frye standard (some states) govern admissibility of expert testimony; reliability and relevance are key.

Expert testimony must be based on sufficient facts, reliable methods, and proper application of those methods to the case.

The IME physician should obtain informed consent for examination, explain the purpose, and document findings contemporaneously.

The examiner should distinguish objective findings from subjective complaints and state the basis for opinions with reasonable medical probability.

Deposition testimony should be limited to opinions disclosed in the report unless the rules permit supplementation.

Confidentiality and HIPAA apply to records reviewed; the examiner should not disclose protected health information beyond the authorized purpose.

A complete record review includes all treating records, imaging reports, operative notes, and prior medical history; missing records should be identified.

Reports should state the examiner's qualifications, records reviewed, examination findings, diagnosis, causation opinion, and impairment rating.

Opinions should be stated to a reasonable degree of medical probability, not certainty, and should identify the basis for each conclusion.

Chronology and timeline analysis helps identify inconsistencies between reported mechanism and documented findings.

Deposition preparation includes reviewing the report, anticipating cross-examination, and understanding the difference between fact and opinion testimony.

The witness should answer only the question asked, avoid speculation, and correct errors promptly on the record.

Privilege and work-product protections may limit discoverability of draft reports; jurisdiction rules vary.

Documentation should be objective, avoid conclusory language, and distinguish the examiner's findings from the patient's reports.

Physicians owe a duty of honesty and objectivity to the legal system; advocacy for a party must not compromise medical accuracy.

Conflicts of interest, including financial relationships with retaining parties, must be disclosed and managed.

Informed consent for examination and treatment requires disclosure of purpose, risks, and alternatives; the IME context differs from treatment.

HIPAA privacy rules govern use and disclosure of protected health information; legal proceedings may require authorization or court order.

The physician should avoid dual roles (treating physician and expert) where objectivity could be compromised.

Professional codes (e.g., AMA Code of Medical Ethics) prohibit false testimony and require reporting of unethical conduct.

Regulatory compliance includes licensure, continuing education, and adherence to state workers' compensation and disability evaluation rules.

Documentation must be accurate and not altered after the fact; late entries should be clearly identified as such.