Background:

As extracorporeal shock wave therapy (ESWT) can enhance healing of skin graft donor sites, this study focused on shock wave effects in burn wounds.

Methods:

A predefined cohort of 50 patients (6 with incomplete data or lost to follow-up) with acute second-degree burns from a larger study of 100 patients were randomly assigned between December 2006 and December 2007 to receive standard therapy (burn wound debridement/topical antiseptic therapy) with (n= 22) or without (n= 22) defocused ESWT (100 impulses/cm 2 at 0.1 mJ/mm 2) applied once to the study burn, after debridement. Randomization sequence was computer-generated, and patients were blinded to treatment allocation. The primary endpoint, time to complete burn wound epithelialization, was determined by independent, blinded-observer. A worst case scenario was applied to the missing cases to rule out the impact of withdrawal bias.

Results:

Patient characteristics across the 2 study groups were balanced (P> 0.05) except for older age (53±17 vs. 38±13 years, P= 0.002) in the ESWT group. Mean time to complete (≥ 95%) epithelialization (CE) for patients that did and did not undergo ESWT was 9.6±1.7 and 12.5±2.2 days, respectively (P< 0.0005). When age (continuous variable) and treatment group (binary) were examined in a linear regression model to control the baseline age imbalance, time to CE, age was not significant (P= 0.33) and treatment group retained significance (P< 0.0005). Statistical significance (P= 0.001) was retained when ESWT cases with missing follow-up were assigned the longest time to CE and when controls with missing follow-up were assigned the shortest time to CE.

Conclusions:

In this randomized phase II study, application of a single defocused shock wave treatment to the superficial second-degree burn wound after debridement/topical antiseptic therapy significantly accelerated epithelialization. This finding warrants confirmation in a larger phase III trial (ClinicalTrials. gov identifier: NCT01242423).