What is ACOEM?

The American College of Occupational and Environmental Medicine (ACOEM) is a professional medical organization that develops evidence-based clinical guidelines for occupational health care and disability management. Founded in 1916, ACOEM is recognized as the preeminent authority on occupational medicine practice guidelines.

ACOEM's guidelines are used nationwide to help physicians make treatment decisions for work-related injuries and illnesses. In California, these guidelines form the foundation of the state's official medical treatment standards for workers' compensation cases.

California's Medical Treatment Utilization Schedule (MTUS)

The Medical Treatment Utilization Schedule (MTUS) is California's official set of evidence-based medical treatment guidelines for workers' compensation. Codified in California Code of Regulations, Title 8, Sections 9792.20 through 9792.27.23, the MTUS determines what medical care is considered "reasonable and necessary" for work-related injuries.

Key Point: The MTUS guidelines are presumed correct on the issue of extent and scope of medical treatment. This means the adopted ACOEM Guidelines should guide treatment decisions in most California workers' compensation cases.

How ACOEM Guidelines Affect Your Claim

When your treating physician requests medical treatment for your work injury, that request goes through a process called Utilization Review (UR). The UR reviewer uses the MTUS (which incorporates ACOEM guidelines) to determine whether the requested treatment should be approved or denied.

The Treatment Authorization Process

  1. Request for Authorization (RFA): Your treating physician submits an RFA to the claims administrator requesting specific treatment or medications.
  2. Utilization Review: A UR physician reviews the request against MTUS/ACOEM guidelines to determine if the treatment is medically necessary.
  3. Decision: The UR reviewer approves, modifies, delays, or denies the request.
  4. Independent Medical Review (IMR): If treatment is denied, you can appeal through IMR. The IMR reviewer is also bound by MTUS guidelines.

Important: Because MTUS guidelines are presumed correct, getting treatment approved outside these guidelines requires substantial medical evidence to justify departure from the standard recommendations.

Current ACOEM Guidelines Adopted in California

California has adopted numerous ACOEM guidelines covering specific body parts and conditions. The Division of Workers' Compensation (DWC) regularly updates these guidelines to reflect current medical evidence.

Body Part-Specific Guidelines

  • Low Back Disorders (Effective November 23, 2021)
  • Shoulder Disorders (Effective August 10, 2023)
  • Hand, Wrist and Forearm Disorders (Effective November 10, 2023)
  • Cervical and Thoracic Spine Disorders (Effective April 18, 2019)
  • Elbow Disorders (Effective April 18, 2019)
  • Knee Disorders (Effective September 21, 2020)
  • Ankle and Foot Disorders (Effective April 18, 2019)

Condition-Specific Guidelines

  • Chronic Pain Guideline (Updated December 2024)
  • Cannabis Guideline (Effective June 1, 2025)
  • Workplace Mental Health (Effective August 11, 2019)
  • Posttraumatic Stress Disorder (Effective April 18, 2019)
  • Initial Approaches to Treatment
  • Opioids Guidelines

Recent and Upcoming MTUS Updates (2025-2026)

The DWC continues to update the MTUS to incorporate the latest ACOEM guideline revisions. Recent updates include:

MTUS Drug List Update (Effective August 6, 2025)

Administrative Director George Parisotto issued an order updating the MTUS Drug List based on changes to the ACOEM Chronic Pain Practice Guideline (December 19, 2024). This update affects which medications are recommended for chronic pain treatment.

Cannabis Guideline (Effective June 1, 2025)

The cannabis guideline provides evidence-based recommendations on marijuana use for occupational injuries. Key findings include:

  • Cannabis is not recommended for treatment of typical work-related conditions
  • No quality evidence supports efficacy for back pain, chronic radiculopathy, or neuropathic pain
  • Cannabis use is not recommended for those in safety-sensitive positions
  • There are documented adverse effects including cardiovascular diseases and psychotic disorders

Workplace Mental Health Guideline (October 2025)

A December 19, 2025 public hearing addressed updates to the Workplace Mental Health Guideline, including the Introduction to Workplace Mental Health and Posttraumatic Stress Disorder guidelines (ACOEM October 1, 2025).

What ACOEM Guidelines Cover

ACOEM guidelines provide comprehensive recommendations for occupational health care, including:

  • Diagnostic Testing: Which tests are appropriate for specific conditions and when imaging should be used
  • Treatment Modalities: Recommended treatments including physical therapy, medications, injections, and surgical interventions
  • Treatment Duration: Expected timeframes for various treatments and frequency of visits
  • Return to Work: Guidelines for functional improvement and return to work activities
  • Medication Management: Appropriate use of medications including opioids, NSAIDs, and other drug classes
  • Surgical Criteria: When surgery is indicated and what conservative treatment should be tried first

When Treatment Is Denied Under MTUS

If your requested treatment is denied because it does not align with MTUS guidelines, you have options:

Independent Medical Review (IMR)

IMR is the primary appeal process for UR denials. An independent physician reviews the denial and determines whether the treatment should be approved. The IMR reviewer also applies MTUS guidelines but may interpret them differently.

Rebutting the Presumption

While MTUS guidelines are presumed correct, this presumption can be rebutted with substantial medical evidence showing that:

  • The recommended treatment is not appropriate for your specific condition
  • Your case involves unique circumstances not addressed by the guidelines
  • More recent medical evidence supports alternative treatment
  • Standard treatments have failed and alternative approaches are necessary

Attorney Tip: Successfully challenging MTUS-based denials often requires detailed medical reports from your treating physician explaining why the guidelines should not apply to your specific situation.

Accessing MTUS/ACOEM Guidelines

Healthcare providers treating, evaluating, or performing utilization review in the California workers' compensation system can access the MTUS (ACOEM) Guidelines and MTUS Drug List at no cost by registering at:

https://www.mdguidelines.com/MTUS

The official DWC MTUS page with regulatory information and updates is available at:

https://www.dir.ca.gov/dwc/mtus/mtus.html

Treatment Denied? We Can Help

If your medical treatment has been denied based on MTUS guidelines, Attorney Nathan Howser can review your case and help you understand your options. Many treatment denials can be successfully appealed through the IMR process.

Call (213) 377-5513Free Consultation