OBJECTIVE To study the effects of secondary wound closure on intramuscular pressure (IMP) in patients treated by fasciotomy for acute compartment syndrome. METHODS Prospective experimental study with an unbiased observer. METHODS Twelve patients (mean age, thirty years) were treated for acute compartment syndrome by fasciotomy, early postoperative edema reduction, and secondary wound closure on the third or fourth day. The syndrome was confirmed by measurements of IMP in seven legs, three thighs, and two arms. The IMP was recorded in appropriate compartments with a noninfusion technique before, during, and after secondary wound closure by wire sutures. The IMP was not allowed to exceed thirty millimeters of mercury (four kilopascals) in the underlying compartment during wound closure. Patients were followed up at thirty-six months after surgery. RESULTS By using an IMP limit of thirty millimeters of mercury, local perfusion pressure remained above fifty millimeters of mercury in all patients. With this protocol, the wound was closed on the third or fourth day in five patients. Seven patients needed repeated secondary wound closure. The distance between skin edges did not exceed 0.5 centimeter in any of the patients by the eleventh day. No patient needed skin transplantation. None had signs of ischemic contracture at follow-up. CONCLUSIONS Secondary wound closure or wound adaptation starting on the third day after fasciotomy seems to be a safe method of treatment in normotensive patients if IMP during wound closure is not allowed to exceed thirty millimeters of mercury.