L90.5

Scar conditions and fibrosis of skin

L90.5 is a clinical designation for various non-keloid permanent skin alterations resulting from the replacement of healthy dermis with fibrous connective tissue. This condition, commonly referred to as cicatrization, represents the end stage of wound repair following injury, inflammation, or surgical intervention. Unlike keloids (coded elsewhere), these scars generally remain within the boundaries of the original insult. The category includes adherent scars, which are tethered to underlying structures like fascia or muscle, atrophic scars characterized by a loss of tissue volume (common in post-acne or post-varicella states), and hypertrophic scars which are raised but stable. Cutaneous fibrosis within this code can also refer to localized hardening of the skin due to chronic inflammatory processes or thermal injury, potentially leading to significant functional impairment if the tissue loses elasticity over joint surfaces.

Clinical Symptoms

  • Visible cutaneous elevations or depressions at the site of prior injury
  • Altered skin texture (indurated, shiny, or thinned)
  • Hypopigmentation or hyperpigmentation of the affected area
  • Loss of adnexal structures (absence of hair follicles or sweat glands within the scar)
  • Pruritus (itching) during the remodeling phase
  • Pain or localized tenderness
  • Restricted range of motion or contractures if located near joints
  • Skin tightness and reduced elasticity
  • Increased sensitivity to mechanical friction or ultraviolet light

Common Causes

  • Post-surgical wound healing and incision remodeling
  • Physical trauma including deep lacerations and abrasions
  • Thermal, chemical, or electrical burns (second and third-degree)
  • Chronic inflammatory skin diseases such as acne vulgaris or hidradenitis suppurativa
  • Infectious processes including cutaneous tuberculosis, cellulitis, or severe varicella
  • Localized cutaneous reactions to radiation therapy
  • Secondary healing of chronic cutaneous ulcers (e.g., venous or pressure ulcers)
  • Complications from piercing or cosmetic procedures

Documentation & Coding Tips

Document the specific etiology of the scar to distinguish between post-traumatic, post-surgical, and post-inflammatory fibrosis.

Example: Patient presents with a 12cm linear scar on the right anterior thigh following an ORIF procedure 14 months ago. The scar is currently adherent to underlying fascia (billingFocus: post-surgical etiology and laterality). Patient has a history of smoking which has contributed to delayed wound healing and increased fibrosis (riskAdjustment: tobacco use as a factor complicating healing).

Billing Focus: Identify the origin of the scar (surgical vs trauma) to justify specific repair codes.

Describe the functional impact of the scar, especially if it causes a contracture or limits joint mobility.

Example: Evaluation of a 4cm fibrotic scar on the palmar surface of the left hand. The scar exhibits significant contracture, limiting the extension of the MCP joint to 15 degrees (billingFocus: functional limitation and anatomical site). This condition requires ongoing physical therapy due to the patients underlying rheumatoid arthritis (riskAdjustment: comorbid autoimmune condition impacting joint function).

Billing Focus: Documentation of limited range of motion supports the medical necessity of physical therapy or surgical release.

Specify the precise dimensions and morphology of the scar to support surgical or procedural necessity.

Example: The patient has a 15 square cm area of cutaneous fibrosis on the central chest. The tissue is indurated and erythematous, consistent with post-burn scar conditions (billingFocus: total area and morphological description). Patient has poorly controlled Type 2 Diabetes Mellitus, increasing the risk for secondary infection and skin breakdown (riskAdjustment: diabetes as a chronic complication for wound management).

Billing Focus: Surface area measurements are required for calculating CPT codes for skin grafts or tissue rearrangements.

Differentiate between L90.5 and L91.0 by confirming the absence or presence of keloid or hypertrophic overgrowth.

Example: Examination of the posterior neck reveals a 3cm scar condition characterized by fibrosis and tethering to the dermis, but without the raised, excessive collagen growth seen in keloids (billingFocus: specificity in scar type). The patient is currently being monitored for morbid obesity, which complicates the assessment of deep tissue fibrosis (riskAdjustment: obesity as a factor in post-surgical complication risk).

Billing Focus: Accurate differentiation prevents claim denials for more expensive keloid treatments.

Include associated sensory symptoms such as pruritus, pain, or dysesthesia localized to the scar site.

Example: Patient reports chronic sharp pain and intense pruritus associated with a 6cm fibrotic scar on the right shoulder (billingFocus: symptomatic presentation and laterality). The patient also suffers from chronic pain syndrome, requiring a multi-modal approach to scar management (riskAdjustment: chronic pain syndrome as an additive risk factor).

Billing Focus: Symptom documentation justifies the use of intralesional injections or topical treatments.

Relevant CPT Codes