Osteoarthritis of knee — ICD-10 M17.2

ICD-10: M17.2 | Category: Osteoarthritis | Billable: Yes

Osteoarthritis (OA) of the knee, classified under ICD-10 code M17.2, is a degenerative joint disease characterized by the breakdown of cartilage, leading to pain, stiffness, and functional impairment. It is one of the most common forms of arthritis, affecting millions worldwide, particularly older adults. The knee joint, being a weight-bearing joint, is particularly susceptible to the effects of OA due to its complex structure and function.

The knee joint is a hinge joint formed by the femur (thigh bone), tibia (shin bone), and patella (kneecap). It is surrounded by a synovial capsule that contains synovial fluid, which lubricates the joint. The primary structures involved in knee stability include:

• Articular Cartilage: A smooth tissue that covers the ends of bones in the joint, facilitating movement.
• Menisci: C-shaped cartilaginous structures that act as shock absorbers and improve joint congruence.
• Ligaments: The anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) provide stability during movement.
• Muscles: The quadriceps and hamstrings play crucial roles in knee function and stability.

Biomechanically, the knee experiences significant forces during weight-bearing activities such as walking, running, and jumping. As individuals age or engage in repetitive stress activities, these forces can lead to cartilage degeneration and subsequent osteoarthritis.

Patient presents with chronic knee pain, particularly aggravated by weight-bearing activities and morning stiffness lasting less than 30 minutes. Physical examination reveals tenderness and crepitus in the right knee, with joint space narrowing observed on X-ray. Code as M17.2 because the patient has osteoarthritis of the knee confirmed by clinical findings and imaging studies, indicating bilateral involvement.

To support medical necessity and prevent claim denials for ICD-10 code M17.2, key documentation elements include:

1. Detailed Patient History: Documenting the onset, duration, and progression of symptoms, including any prior treatments and their outcomes.

1. Clinical Findings: Clear description of physical examination results, including joint tenderness, swelling, and range of motion limitations.

1. Diagnostic Imaging: Inclusion of imaging reports that confirm osteoarthritis diagnosis, such as X-rays showing joint space narrowing or osteophytes.

1. Treatment Plan: Comprehensive documentation of the treatment plan, including any referrals for physical therapy, prescribed medications, and patient education materials.

1. Follow-Up Notes: Evidence of patient follow-up visits to monitor the condition and response to treatment, demonstrating ongoing management of the condition.

Subjective: A 67-year-old female presents with complaints of right knee pain that worsens with activity and improves with rest. She reports difficulty climbing stairs and has noticed swelling in the knee joint. Objective: On examination, the right knee exhibits tenderness to palpation along the medial joint line, with mild effusion noted. Range of motion is limited to 90 degrees flexion. X-rays show joint space narrowing and osteophyte formation. Assessment: The patient is diagnosed with bilateral osteoarthritis of the knee, primarily affecting the right side (ICD-10 Code M17.2). Plan: Initiate a treatment plan including physical therapy focused on strengthening and flexibility, recommend weight loss strategies, and consider a trial of NSAIDs for pain management. Follow-up appointment in six weeks to assess progress.

Several conditions may mimic or co-exist with knee osteoarthritis:

1. Rheumatoid Arthritis (M05): An autoimmune condition causing joint inflammation and systemic symptoms.
2. Patellofemoral Pain Syndrome (M25.5): Characterized by anterior knee pain without significant structural changes.
3. Meniscal Tear (S83.2): Injury leading to mechanical symptoms like locking or catching.
4. Gout (M10): Crystal-induced arthritis presenting with acute pain and swelling.

Accurate documentation is essential for billing purposes under ICD-10 code M17.2:

Key Elements for Documentation:

1. Detailed history including onset, duration, location, intensity of pain, and functional limitations.
2. Physical examination findings documenting range of motion deficits, swelling, tenderness, etc.
3. Imaging results supporting diagnosis must be included in the medical record.

Billing Guidance:

Ensure that all services provided are documented clearly in EMR systems to support claims for physical therapy sessions, imaging studies, or consultations.