L89.90

Pressure ulcer of unspecified site, unspecified stage

Pressure ulcer of unspecified site, unspecified stage, also known as a decubitus ulcer or pressure injury, represents a localized injury to the skin and/or underlying soft tissue, typically over a bony prominence or related to a medical or other device. This specific code is utilized when clinical documentation fail to specify both the anatomical location and the severity (stage) of the pressure injury. These injuries occur due to intense or prolonged pressure in combination with shear. The tolerance of soft tissue for pressure and shear may also be affected by microclimate, nutrition, perfusion, co-morbidities, and condition of the soft tissue. While this code (L89.90) is billable, it is considered a non-specific diagnosis and may be subject to payer scrutiny, as it does not clarify if the ulcer involves the elbow, back, hip, buttock, ankle, or heel, nor does it specify the depth of tissue loss ranging from non-blanchable erythema (Stage 1) to full-thickness skin and tissue loss (Stage 4).

Clinical Symptoms

  • Localized skin redness that does not turn white when pressed (non-blanchable erythema)
  • Localized pain, tenderness, or discomfort at a site of prolonged pressure
  • Localized edema (swelling) or induration (firmness) of the skin
  • Skin temperature changes, being either warmer or cooler than surrounding areas
  • Skin discoloration, including purple or maroon localized areas in deep tissue injuries
  • Partial-thickness loss of dermis presenting as a shallow open ulcer or a blister
  • Full-thickness skin loss involving exposure of subcutaneous fat
  • Full-thickness tissue loss with exposed bone, tendon, or muscle
  • Presence of slough (yellow, tan, gray, green, or brown) or eschar (tan, brown, or black) in the wound bed
  • Serosanguinous or purulent drainage if an infection is present

Common Causes

  • Prolonged external pressure on soft tissues leading to localized ischemia
  • Shear force caused by skin staying in place while the underlying bone and fascia move
  • Friction from skin rubbing against surfaces such as bed linens or clothing
  • Immobility due to paralysis, prolonged sedation, frailty, or coma
  • Excessive moisture from fecal or urinary incontinence causing skin maceration
  • Inadequate nutrition, specifically protein-calorie malnutrition and dehydration
  • Sensory perception deficits (e.g., peripheral neuropathy, spinal cord injury) that prevent the patient from feeling discomfort
  • Peripheral vascular disease or diabetes mellitus reducing blood flow to tissues
  • Age-related skin changes, including thinning of the dermis and loss of subcutaneous fat

Documentation & Coding Tips

Move beyond unspecified designations by documenting precise anatomical location and laterality.

Example: Patient presents with a persistent skin breakdown on the right ischial tuberosity. Physical exam reveals a 3cm x 4cm lesion with full thickness skin loss and visible subcutaneous fat. Diagnosis: Stage 3 pressure ulcer of the right buttock. Billing Focus: Right buttock location (L89.313). Risk Adjustment: Stage 3 severity maps to a higher HCC weight than unspecified codes.

Billing Focus: Anatomical site and laterality (Right vs. Left).

Clearly distinguish between Unstageable and Unspecified stages in clinical documentation.

Example: Wound on the left heel is entirely covered by dark, adherent eschar, precluding visual assessment of the wound bed depth. Management includes enzymatic debridement. Diagnosis: Unstageable pressure ulcer of the left heel. Billing Focus: Unstageable status (L89.620). Risk Adjustment: Unstageable ulcers are treated as high-severity for risk adjustment purposes.

Billing Focus: Documentation of why the stage cannot be determined (e.g., eschar or slough).

Incorporate nutritional status and comorbid conditions that impede wound healing.

Example: The patient has a pressure ulcer of the sacral region, stage 2. Patient also has Type 2 diabetes and severe protein-calorie malnutrition which are complicating the healing process. Albumin is 2.8. Diagnosis: Pressure ulcer of sacrum, stage 2 with comorbid severe malnutrition. Billing Focus: Inclusion of E43 for malnutrition. Risk Adjustment: Malnutrition is a major complication/comorbidity (MCC) that increases the encounter complexity.

Billing Focus: Secondary diagnoses like Diabetes (E11.621) or Malnutrition (E43).

Document wound measurements and characteristics at every encounter to justify debridement levels.

Example: Sacral pressure ulcer measuring 5cm x 6cm with 2cm depth. Selective debridement performed on 12 square cm of necrotic tissue. No involvement of bone or muscle. Diagnosis: Stage 3 pressure ulcer of sacrum. Billing Focus: Square centimeters debrided for CPT 11042. Risk Adjustment: Severity of tissue loss determines the specific ICD-10 code and HCC tier.

Billing Focus: Specific dimensions (length, width, depth) and tissue type (necrotic, granulation).

Specify if the ulcer is present on admission (POA) for inpatient encounters.

Example: Upon admission from the skilled nursing facility, a Stage 2 pressure ulcer was identified on the left olecranon. Skin was intact at last check 24 hours ago according to transfer notes. Diagnosis: Pressure ulcer left elbow, stage 2, POA: Yes. Billing Focus: POA indicator status. Risk Adjustment: Prevents the facility from being penalized for a hospital-acquired condition (HAC).

Billing Focus: POA (Present on Admission) indicator for inpatient claims.

Relevant CPT Codes