Z86.31

Personal history of diabetic foot ulcer

Z86.31 is a specific ICD-10-CM code utilized to document a patient's historical medical history of a diabetic foot ulcer (DFU). In clinical practice, this code signifies that while the ulcer is currently resolved or healed, the patient remains at an exceptionally high risk for recurrence. A history of DFU is considered one of the primary risk factors for future ulceration, with recurrence rates estimated at roughly 40% within the first year after healing. The existence of a prior ulcer indicates significant underlying diabetic complications, most notably peripheral sensory neuropathy (loss of protective sensation), autonomic neuropathy (causing dry skin and fissures), and often peripheral arterial disease (impaired micro- and macrocirculation). Clinical management for patients with this history focuses on aggressive secondary prevention, including daily foot inspections, specialized therapeutic footwear, regular professional podiatric evaluations, and optimized glycemic control to prevent complications such as cellulitis, osteomyelitis, and lower-extremity amputation.

Clinical Symptoms

  • Presence of scar tissue or remodeled skin at the site of a previous ulcer
  • Localized hyperkeratosis or callus formation over high-pressure areas
  • Loss of protective sensation (LOPS) as determined by monofilament testing
  • Evidence of diabetic peripheral neuropathy (numbness, tingling, or burning)
  • Anhidrosis or dry, scaling skin (xerosis) on the feet
  • Structural foot deformities such as hammertoes, bunions, or Charcot foot
  • Abnormal gait or pressure distribution during ambulation
  • Reduced pedal pulses or cold extremities suggestive of peripheral vascular involvement
  • History of localized erythema or warmth at previous wound sites

Common Causes

  • Chronic hyperglycemia associated with Diabetes Mellitus Type 1 or Type 2
  • Diabetic peripheral sensory neuropathy resulting in loss of protective sensation
  • Autonomic neuropathy leading to skin dryness and cracking
  • Motor neuropathy causing intrinsic muscle atrophy and subsequent foot deformity
  • Peripheral arterial disease (PAD) causing chronic limb ischemia
  • Repetitive mechanical stress or high plantar pressures
  • Use of ill-fitting or inappropriate footwear
  • History of minor trauma that previously led to skin breakdown
  • Inadequate foot self-care and hygiene practices

Documentation & Coding Tips

Distinguish between active ulcers and history of ulcers to ensure HCC capture.

Example: Patient with Type 2 Diabetes Mellitus presents for foot exam. History includes a Stage 3 diabetic foot ulcer of the right heel, which fully healed 6 months ago. Current exam shows no active breakdown or drainage. Plan: Regular monitoring for recurrence. Coding: E11.9 (Type 2 diabetes mellitus without complications) and Z86.31 (Personal history of diabetic foot ulcer).

Billing Focus: Document that the previous ulcer is fully epithelialized and no longer requires active wound care to justify the history code.

Identify the specific anatomical site of the resolved ulcer in the history.

Example: Clinical documentation reflects a personal history of a diabetic ulcer specifically located on the left first metatarsal head. This anatomical specificity supports medical necessity for therapeutic shoe inserts (A5500).

Billing Focus: Laterality and specific foot location (e.g., heel, midfoot, metatarsal) should be specified in the narrative even if the code Z86.31 is not site-specific.

Document the underlying type of diabetes associated with the historical ulcer.

Example: Patient has a history of foot ulcers secondary to Type 1 Diabetes Mellitus with peripheral neuropathy. Past ulcer was located on the left lateral malleolus. Current skin is intact with hypertrophic scarring at the site.

Billing Focus: Always code the underlying diabetes mellitus (E10.- or E11.-) as the primary diagnosis followed by Z86.31.

Specify the presence of comorbid peripheral neuropathy or vascular disease.

Example: History of diabetic foot ulcer on right great toe. Patient currently has loss of protective sensation (LOPS) confirmed by 10g monofilament test and evidence of peripheral angiopathy.

Billing Focus: Linking the history of ulcer to current neuropathy (E11.40) or PVD (E11.51) justifies more frequent preventative podiatry visits.

Incorporate the status of any prior amputations related to the ulcer history.

Example: History of diabetic foot ulcer on left foot which resulted in a previous transmetatarsal amputation. Currently checking the stump for any new pressure points or signs of breakdown.

Billing Focus: Combine Z86.31 with Z89.432 (Acquired absence of left foot below ankle) to provide a complete clinical picture of the patient's morbidity.

Relevant CPT Codes