Undermining Apices in Surgical Wounds

Undermining Apices in Surgical Wounds: a Randomized Evaluator-blinded Split-wound Comparative Effectiveness Trial

When patients have surgery on the neck, trunk, arms, or legs, stitches are the standard way to close the wound. Wounds always result in a scar, but doctors are always looking for ways to reduce scarring. Several studies have been done to test ways to close wounds that reduce scarring. One idea is to reduce the tension around the cut. One way to reduce tension is to free up the skin around the wound. This procedure is also called "undermining". Some studies have shown that freeing up the skin near the tips of the wound, called the "apices," is helpful for improving the cosmetic outcome of scars. This study will investigate if there are any differences in the appearances of the scar if one tip is undermined and the other is not.

Study Overview

• Status: Enrolling by invitation
• Conditions: Scarring
• Intervention / Treatment: Other: Apical Undermining

Detailed Description

Reducing scar tissue formation and postoperative complications in wound closure has remained the focus of recent studies and decreases the cost and time burden of follow-up visits and procedures. Such studies have highlighted the impact of mechanical forces and tension on scar formation, demonstrating that reducing the mechanical stress within the wound environment results in better aesthetic outcomes. Undermining peripheral and apices of the wound has been used in the closure of large and tight defects allowing the closure of these wounds by reducing the tension. Undermining has been shown to reduce tension, and peripheral and apical undermining has been recommended for decreasing scar formation. However, extensive undermining may increase the complications of the surgery by reducing vascularization and creating a space for hematomas. To our knowledge, the impact of scar cosmesis and the rate of postoperative complications in apical undermining in the linear repair of surgical wounds have not been studied, and it remains unknown whether undermining the apices can decrease the protrusion of the scar tissue at the edges. This study seeks to determine the effectiveness of apical undermining of linear wound closures in improving scar cosmesis by using individuals as their own controls in a split-scar model.

This is a single center, randomized, evaluator-blinded, split wound study.

After screening and informed consent, demographic data will be collected including age, race, gender, and medical record number. This will be collected within the Redcap database.

The patient's wound will be labeled A if it is on the left or superior side of the investigator and B if it is on the right or inferior side. A concealed randomization result will be obtained from the Redcap randomization module, which will specify which side, A or B, will receive apical undermining

Following this, both sides of the wound will be sutured together with a subcutaneous (bottom) layer of stitches. Next, a cutaneous layer of sutures will be placed, as is the standard of care. A digital image of the wound after the epidermal closure will be obtained; these may be used in scientific talks and/or for publication purposes. The patient will then be instructed to continue dressing changes along the entire length of the surgical site until the wound is fully healed as is the standard of care.

Treatment assignment, wound length, demographic data, and digital images will be recorded within the Redcap database. Follow-up assessment will be scheduled for three months following the procedure, with a one-month window before or after that time if the patient cannot return at precisely three months.

• Study Type: Interventional
• Enrollment (Estimated): 50
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • California
    • Sacramento, California, United States, 95816
      • University of California, Davis - Dermatology Department

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• 18 years of age or older
• Able to give informed consent themselves
• Patient scheduled for cutaneous surgical procedure on the neck, trunk, and extremities with predicted primary closure
• Willing to return for follow-up visit

Exclusion Criteria:

• Incarceration
• Under 18 years of age
• Pregnant women
• Unable to understand written and oral English
• Wounds with predicted closure length less than 3cm

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: Randomized
• Interventional Model: Factorial Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
No Intervention: Linear Wound Closure; A cutaneous layer of sutures will be placed on one side, as is standard of care.
Experimental: Linear Wound Closure with Apical Undermining; The other side of the wound will have a cutaneous layer of sutures, as is standard of care, and will receive apical undermining.	Other: Apical Undermining; The skin at the tip of the wound will be freed to reduce tension.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Observer Scar Assessment as measured by Patient Observer Scar Assessment Score (POSAS)	The primary endpoint will be the score of two blinded reviewers independently using the POSAS assessment. The observer scale of the POSAS consists of six items (vascularity, pigmentation, thickness, relief, pliability, and surface area). All items are scored on a scale ranging from 1 ("like normal skin") to 10 ("worst scar imaginable"). The sum of the six items results in a total score of the POSAS observer scale. Furthermore, an overall opinion is scored on a scale ranging from 1 to 10. All parameters should preferably be compared to normal skin on a comparable anatomic location.	3 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Width of Scar as measured using Trace-to-Tape Method	The trace-to-tape method is an objective measure for linear postoperative scars. The mean scar width will be determined using the trace-to-tape method. The surface area of the scar will be collected by tracing the scar with a water-based gel pen. While still wet, the gel residue will be lifted from the skin with clear packing tape and transferred on a sheet of paper.	3 months
Complications or Adverse Events from Treatment	For example, if one half of the scar has more associated erythema, as measured using the Trace-to-Tape method, then it will be recorded. Other complications from the treatment will also be recorded.	3 months
Patient Scar Assessment as measured by Patient Observer Scar Assessment Score (POSAS)	This is the patient portion of the POSAS assessment, which will be independently recorded. The patient scale of the POSAS consists of six items (pain, itch, thickness, color, stiffness, and irregularity). All items are scored on a scale ranging from 1 ("as normal skin") to 10 ("yes, very different"). The sum of the six items results in a total score of the POSAS patient scale. Furthermore, an overall opinion is scored on a scale ranging from 1 to 10.	3 months

Collaborators and Investigators

• Sponsor: University of California, Davis
• Investigators: Principal Investigator: Daniel Eisen, MD, University of California, Davis - Dermatology

Publications and helpful links

General Publications

• Barnes LA, Marshall CD, Leavitt T, Hu MS, Moore AL, Gonzalez JG, Longaker MT, Gurtner GC. Mechanical Forces in Cutaneous Wound Healing: Emerging Therapies to Minimize Scar Formation. Adv Wound Care (New Rochelle). 2018 Feb 1;7(2):47-56. doi: 10.1089/wound.2016.0709.
• Gurtner GC, Dauskardt RH, Wong VW, Bhatt KA, Wu K, Vial IN, Padois K, Korman JM, Longaker MT. Improving cutaneous scar formation by controlling the mechanical environment: large animal and phase I studies. Ann Surg. 2011 Aug;254(2):217-25. doi: 10.1097/SLA.0b013e318220b159.
• Krishnan NM, Brown BJ, Davison SP, Mauskar N, Mino M, Jordan MH, Shupp JW. Reducing Wound Tension with Undermining or Imbrication-Do They Work? Plast Reconstr Surg Glob Open. 2016 Jul 13;4(7):e799. doi: 10.1097/GOX.0000000000000799. eCollection 2016 Jul.
• Zitelli JA. TIPS for a better ellipse. J Am Acad Dermatol. 1990 Jan;22(1):101-3. doi: 10.1016/0190-9622(90)70016-b.
• Jonathan K (Ed). Dermatologic Surgery. McGraw-Hill Education. 2018. ISBN: 978-1-25-964392-7.

Study record dates

Study Major Dates

• Study Start (Actual): August 9, 2023
• Primary Completion (Estimated): December 31, 2026
• Study Completion (Estimated): March 31, 2027

Study Registration Dates

• First Submitted: February 24, 2023
• First Submitted That Met QC Criteria: February 24, 2023
• First Posted (Actual): March 7, 2023

Study Record Updates

• Last Update Posted (Actual): February 10, 2026
• Last Update Submitted That Met QC Criteria: February 6, 2026
• Last Verified: February 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Pathologic Processes; Fibrosis; Pathological Conditions, Signs and Symptoms; Cicatrix
• Other Study ID Numbers: 1999193

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No