Diseases of the musculoskeletal system
This chapter covers ICD-10-CM codes in the range M00-M99 for diseases of the musculoskeletal system and connective tissue. Covers diseases of the musculoskeletal system and connective tissue including arthropathies, dorsopathies, and osteoporosis.
Chapter Overview
Key Statistics
- •Contains 17 categories and 73 total codes
- •Includes 26 billable codes and 47 non-billable codes
- •Chapter range: M00-M99
Clinical Relevance
Essential for orthopedic, rheumatologic, and musculoskeletal conditions. Critical for orthopedic surgery, rheumatology, and physical medicine.
Documentation Requirements
Requires laterality, joint specificity, and acute vs chronic status. Fracture healing status and complications must be documented.
Special Considerations
Joint replacement complications require specific coding. Osteoarthritis requires joint specificity and severity documentation.
Categories in this Chapter
Infectious arthropathies
Inflammatory polyarthropathies
Osteoarthritis
Other joint disorders
Dentofacial anomalies [including malocclusion] and other disorders of jaw
Systemic connective tissue disorders
Deforming dorsopathies
Spondylopathies
Other dorsopathies
Disorders of muscles
Disorders of synovium and tendon
Other soft tissue disorders
Disorders of bone density and structure
Other osteopathies
Chondropathies
Intraoperative and postprocedural complications and disorders of musculoskeletal system
Biomechanical lesions, not elsewhere classified
Chapter-Specific Coding Guidelines
General Guidelines for Diseases of the musculoskeletal system:
- Arthritis coding requires specification of type and joints affected
- Fracture care has specific time-based coding rules
- Back pain coding needs anatomical specificity
- Use external cause codes for injury-related conditions
Documentation Requirements:
- •Specific musculoskeletal condition and location
- •Acute vs chronic presentation
- •Laterality (right, left, bilateral)
- •Severity and functional impact
- •Underlying causes or triggers
Sequencing Rules:
- Acute conditions typically sequenced before chronic
- Complications sequence according to treatment focus
- Use most specific anatomical codes available
- External causes follow musculoskeletal diagnosis
When to Use:
- ✓For primary musculoskeletal conditions
- ✓When MSK condition affects mobility or function
- ✓For acute injuries or exacerbations
- ✓When documenting chronic MSK diseases
When NOT to Use:
- ✗Normal musculoskeletal findings
- ✗Screening encounters without abnormalities
- ✗Congenital MSK anomalies (use Q codes)
- ✗Post-procedural states without complications
Special Considerations:
- ⚠Rheumatoid arthritis has specific organ involvement codes
- ⚠Osteoarthritis coding includes primary vs secondary
- ⚠Spinal conditions need level-specific documentation
- ⚠Osteoporosis fractures have unique coding rules
Version Updates
2025 updates focus on precision orthopedics, regenerative medicine, and functional outcome measures.
Recent Updates:
Regenerative Medicine Treatments
New codes for stem cell and platelet-rich plasma therapies
Impact: Better tracking of innovative MSK treatments
Functional Assessment Integration
Enhanced coding for patient-reported outcome measures
Impact: Improved documentation of functional status
Implementation Guidance:
- •Update arthritis documentation practices
- •Review fracture care coding protocols
- •Train on regenerative medicine documentation
- •Implement functional outcome coding
Upcoming Changes:
- →Expanded digital health monitoring codes in 2026
- →Enhanced coding for personalized orthopedic treatments
- →New categories for musculoskeletal aging
Related Resources
Key resources for musculoskeletal coding, clinical guidelines, and rehabilitation protocols.
Official Documentation:
Related Chapters:
Tools and References:
Frequently Asked Questions
How do I code different types of arthritis?
Rheumatoid arthritis (M05-M06), osteoarthritis (M15-M19), and other arthropathies (M00-M03) have distinct code ranges. Specify joint involvement and laterality.
What's the difference between acute and chronic back pain coding?
Duration and underlying pathology determine coding. Use M54.- for dorsalgia with appropriate subcategories for location and chronicity.
How do I code fractures in different healing phases?
Initial encounter uses S-codes with 7th character A. Subsequent encounters use appropriate 7th characters (D for routine healing, G for delayed healing, etc.).