A randomized controlled trial of the embrace advanced scar therapy device to reduce incisional scar formation

Abstract

Background: Scarring represents a significant biomedical burden in clinical medicine. Mechanomodulation has been linked to scarring through inflammation, but until now a systematic approach to attenuate mechanical force and reduce scarring has not been possible.

Methods: The authors conducted a 12-month, prospective, open-label, randomized, multicenter clinical trial to evaluate abdominoplasty scar appearance following postoperative treatment with the embrace Advanced Scar Therapy device to reduce mechanical forces on healing surgical incisions. Incisions from 65 healthy adult subjects were randomized to receive embrace treatment on one half of an abdominoplasty incision and control treatment (surgeon's optimal care methods) on the other half. The primary endpoint for this study was the difference between assessments of scar appearance for the treated and control sides using the visual analogue scale scar score.

Results: Final 12-month study photographs were obtained from 36 subjects who completed at least 5 weeks of dressing application. The mean visual analogue scale score for embrace-treated scars (2.90) was significantly improved compared with control-treated scars (3.29) at 12 months (difference, 0.39; 95 percent confidence interval, 0.14 to 0.66; p = 0.027). Both subjects and investigators found that embrace-treated scars demonstrated significant improvements in overall appearance at 12 months using the Patient and Observer Scar Assessment Scale evaluation (p = 0.02 and p < 0.001, respectively). No serious adverse events were reported.

Conclusions: These results demonstrate that the embrace device significantly reduces scarring following abdominoplasty surgery. To the authors' knowledge, this represents the first level I evidence for postoperative scar reduction.

Clinical question/level of evidence: Therapeutic, II.

Trial registration: ClinicalTrials.gov NCT01399099.

Fig. 1

Schematic depiction of the embrace device. (Above, left) The embrace device used in the clinical trial is a 16x5-cm silicone elastomeric dressing that adheres to the skin using a pressure-sensitive silicone adhesive. (Above, center) The user initially opens the applicator approximately 45 degrees and (above, right) the protective liner is peeled back from the adhesive dressing. (Second row, left) The applicator is then fully opened 180 degrees to strain the dressing. (Second row, right) Once fully opened, the device is ready for application. (Third row, left) The dressing is applied directly over the center of the closed incision, and (third row, right) the user firmly presses or rubs the applicator to activate the adhesive. (Below, left) Tabs at the end of the applicator are pulled away to release the dressing and the applicator is discarded, (below, right) after which the dressing remains on for approximately 7 days.

Fig. 2

Flow diagram of clinical trial. Seventy-three subjects were initially assessed for eligibility, with four excluded because of a body mass index (BMI) in excess of 30 and two excluded after canceling surgery. In addition, two were excluded after enrollment but before treatment (one because of a body mass index out of range and the other as a result of missing the treatment window). A total of 65 subjects underwent randomization (self as control), with half of each incision allocated to receive either embrace or control treatment. Eighteen subjects did not complete the study, with 13 discontinuing because of skin irritation, one because of a wound-site infection, and four for miscellaneous reasons. An additional 11 subjects completed treatment but were subsequently lost to follow-up, resulting in 36 subjects included in the final analysis.

Fig. 3

Photographic evaluation. (Above and second row) Patient at 6 months after abdominoplasty surgery. (Above) entire view of abdominoplasty scar. (Second row, left) The embrace-treated side and (second row, right) the control-treated side. The mean visual analogue scale scores for treated and control incisions were 2.13 and 6.87, respectively. Overall subject Patient and Observer Scar Assessment Scale scores were 5 for the treated and 10 for the control incision. Overall investigator Patient and Observer Scar Assessment Scale scores were 2 for the treated and 5 for the control incision. (Third row and below) Patient at 12 months following abdominoplasty surgery. (Third row) Entire view of abdominoplasty scar. (Below, left) The embrace-treated side and (below, right) the control-treated side. The mean visual analogue scale scores for treated and control incisions were 2.60 and 5.27, respectively. Overall subject Patient and Observer Scar Assessment Scale scores were 2 for the treated and 7 for the control incision. Overall investigator Patient and Observer Scar Assessment Scale scores were 2 for the treated and 6 for the control incision.

Fig. 4

Photographic evaluation. (Above and second row) Patient at 6 months after abdominoplasty surgery. (Above) Entire view of abdominoplasty scar. (Second row, left) The embrace-treated side and (second row, right) the control-treated side. The mean visual analogue scale scores for treated and control incisions were 4.52 and 5.90, respectively. Overall subject Patient and Observer Scar Assessment Scale scores were 10 for the treated and 10 for the control incision. Overall investigator Patient and Observer Scar Assessment Scale scores were 2 for the treated and 4 for the control incision. (Third row and below) Patient at 12 months after abdominoplasty surgery. (Third row) Entire view of abdominoplasty scar. (Below, left) The embrace-treated side and (below, right) the control-treated side. The mean visual analogue scale scores for treated and control incisions were 2.53 and 4.40, respectively. Overall subject Patient and Observer Scar Assessment Scale scores were 4 for the treated and 10 for the control incision. Overall investigator Patient and Observer Scar Assessment Scale scores were 1 for the treated and 4 for the control incision.

Fig. 5

Evolution of scar appearance over time. Graph illustrating overall scar appearance as measured by (above) subjects and (below) investigators using the Patient and Observer Scar Assessment Scale (POSAS) at all recorded time points. Error bars represent standard error of the mean. Tx, treatment; Ctrl, control.