Musculoskeletal condition M71.21 — ICD-10 M71.21

ICD-10: M71.21 | Category: Soft Tissue Disorders | Billable: Yes

ICD-10 code M71.21 refers to "Bursitis of the shoulder, left shoulder." Bursitis is an inflammatory condition affecting the bursae—small, fluid-filled sacs that cushion the bones, tendons, and muscles near joints. This condition commonly results from repetitive motion or prolonged pressure on the shoulder joint, leading to pain, swelling, and limited range of motion. Although it can occur in various locations throughout the body, shoulder bursitis is particularly prevalent due to the complex biomechanics of the shoulder girdle.

Understanding bursitis is crucial for clinicians, rehabilitation providers, and patients alike as it informs treatment protocols and recovery expectations. This article will delve into the anatomy and biomechanics of the shoulder, explore the pathophysiology and risk factors associated with M71.21, and provide detailed guidance on diagnosis, treatment, and rehabilitation.

The shoulder joint is a highly mobile structure composed of several bones, including the humerus, scapula, and clavicle. The rotator cuff—comprised of four muscles (supraspinatus, infraspinatus, teres minor, and subscapularis)—plays a critical role in stabilizing the shoulder during movement. The subacromial bursa lies beneath the acromion (a bony projection of the scapula) and above the rotator cuff tendons.

Biomechanics

The shoulder joint's unique ball-and-socket design allows for a wide range of motion, making it susceptible to injuries like bursitis. During overhead activities or repetitive arm movements, friction can occur between the rotator cuff tendons and the acromion, leading to inflammation of the subacromial bursa. This inflammation can restrict movement and cause pain during both active and passive shoulder motions.

Patient presents with bilateral shoulder pain and tenderness, diagnosed with bursitis after physical examination and imaging. Code as M71.21 because the documentation specifies “other specified soft tissue disorder” affecting the subacromial bursae, which aligns with the criteria for this ICD-10 code.

To support medical necessity and prevent claim denials for ICD-10 code M71.21, key documentation elements must be included:

• Detailed History: Comprehensive history of present illness, including onset, duration, and character of symptoms.

• Physical Examination Findings: Clear documentation of the physical examination, including tenderness, range of motion, and any imaging results confirming the diagnosis.

• Treatment Plan: Outline of the treatment plan that includes conservative measures (e.g., physical therapy, medication) and rationale for the chosen interventions.

• Follow-up Requirements: Documentation of follow-up plans to assess the patient’s response to treatment and any adjustments made based on clinical findings.

Subjective: A 45-year-old female presents to the clinic with complaints of persistent pain in her right shoulder that has worsened over the past month. She reports difficulty in overhead activities and experiences sharp pain when reaching. Objective: Upon examination, there is tenderness over the right shoulder with limited range of motion. MRI findings indicate inflammation of the subacromial bursa without rotator cuff tear. Assessment: Right shoulder bursitis, classified under M71.21 (Other specified soft tissue disorders). Plan: The patient is advised to rest the shoulder, apply ice packs, and take NSAIDs for pain relief. A referral to physical therapy is made for rehabilitation exercises focusing on range of motion and strengthening. A follow-up appointment is scheduled in four weeks to monitor progress.

Differential diagnoses for shoulder pain include:

1. Rotator Cuff Tear (M75.121) - Partial or complete tear of rotator cuff tendons.
2. Shoulder Impingement Syndrome (M75.4) - Compression of rotator cuff tendons under acromion.
3. Frozen Shoulder (Adhesive Capsulitis) (M75.0) - Stiffness and pain due to thickening of shoulder capsule.
4. Osteoarthritis (M19.90) - Degenerative joint disease affecting cartilage.

Accurate differentiation is crucial for effective management.

Accurate documentation is vital for billing purposes:

Key Documentation Elements

1. Patient history detailing onset and progression of symptoms.
2. Objective findings from physical examination.
3. Imaging results if performed.
4. Treatment plan including specific interventions used.

Billing Guidance

Ensure that coding accurately reflects the diagnosis (M71.21) along with any additional relevant codes for associated conditions or procedures performed during treatment.