Study objective: Polytraumatized patients with injuries to the thorax constitute a significant percentage of patients with severe types of injuries. Their treatment is usually lengthy and complex, and is aggravated by the occurrence of numerous complications that slow down their recovery and threaten their physical integrity. There are significant factors in reducing the number of complications and overall mortality: a good treatment algorithm, a timely and exact diagnosis, and an adequate and rapid approach toward treating these patients. The objective of this study is to ascertain the value of an early, straightforward surgical method for stabilizing an unstable thorax in polytraumatized patients, as well as its effect on the speed of recovery and general status of polytraumatized patients. Additionally, this study’s objective is to compare the external stabilization treatment method with the internal stabilization treatment method, and to ascertain potential advantages of the external stabilization treatment method as compared to the internal stabilization treatment method. Participants and methods: The study concerns the retrospective analysis of the data from two researched groups of patients. In the first group, 35 patients were treated for an unstable chest wall using the active approach (i.e. -- external surgical stabilization). Surgical procedures to stabilize the chest wall were performed during a period of time from the beginning of 2002 until the middle of 2006. The second group includes 50 patients who were treated for an unstable chest wall using the conservative approach (i.e. – internal pneumatic stabilization with mechanical ventilation). Patients from the second group were treated during a period of time from 1991 until the end of 2001. All patients from both groups were treated in the Intensive Care Unit (ICU) and subsequently in the Department of Thoracic and Vascular Surgery and in other departments of the KBC Rijeka Surgical Clinic. In the review of the treated groups, characteristics were described and discussed with regard to the composition of the patient groups, the type of chest wall instability and its presentation, related injuries within the framework of the picture of polytraumatized patients, and the clinical circumstances of the treatment. Results: In our comparison of the groups over the course of their stay in the Intensive Care Unit and subsequently in hospital departments, we recognize that – given the length of stay, occurrence of complications, and respiratory function – those patients treated with the internal stabilization method stayed in the ICU for a significantly longer period of time compared to those patients treated with the surgical approach. In the group treated with internal stabilization, complications were noted in a significantly greater number of patients, particularly a severe form of complications that have respiratory insufficiency as a sequela. Over the course of their stay in the Intensive Care Unit, mortality was significantly higher in the group treated by means of the internal stabilization method with mechanical ventilation. Patients treated with internal pneumatic support after leaving the Intensive Care Unit stayed in one of the hospital department for a significantly longer period of time in contrast to patients from the group that was operated on. Their recovery was also lengthier. Over the course of their stay in the hospital departments, various complications were noted in a significantly greater number of patients in the group treated with internal stabilization. Furthermore, significantly more complications with an effect on the respiratory function of these patients were evident in this group. By the end of the rehabilitation program, significant respiratory insufficiency with exertion was evident in a greater number of patients from the group treated with mechanical ventilation. There were no deaths in either group during their stay in the hospital departments. Conclusion: The approach to treating polytraumatized patients with related chest wall instability is interdisciplinary and is performed using prompt diagnostic procedures in correlation with an intensively active process and with the active involvement of the surgical specialties. In the present day, treatment of patients with chest wall instability whose respiration is threatened is dichotomous; either it is done using so-called “internal stabilization” with mechanical ventilation or it is done using the external surgical stabilization approach. Pulmonary contusion as a comorbid factor is a particularly aggravated occurrence that has a significant effect on the speed of patient recovery, their general status, and the development of respiratory complications. After proper execution of the procedure involving external stabilization of the chest wall, patients succeed in weaning from mechanical ventilation in a very short period of time postoperatively, and occurrence of surgical complications is negligible. At the present time, the treatment of chest wall instability with external surgical stabilization is the generally-accepted treatment method around the world today. Given the length of treatment, speed of recovery, and development of complications in the patients treated using our modification of earlier recognized surgical techniques, we can assert that it is safe and acceptable for the majority of patients and also has irrefutable advantages in welldocumented cases as compared with the internal stabilization treatment method with mechanical ventilation