<b>Chest Wall Hydatid Disease: Surgical management and risk Factors for Recurrence and Mortality</b>

<b>Preoperative data: </b>For each patient, we collected information about epidemiological and anamnestic data: age, gender, geographical origin (rural or urban), the department of origin (thoracic surgery, orthopedics or neurosurgery), notion of hydatid contagion, family history of hydatid cyst (HC), personal history of visceral hydatid cyst. We consider a history of multiple visceral hydatidosis and hydatid involvement of more than three viscera. We also examined clinical parameters such as the time to consultation (the time from the onset of symptomatology to the date of consultation), time to treatment (the time between the onset of the symptomatology and the date of surgery), the circumstances of discovery, including incidental findings, chest pain, swelling of the soft tissues of the thoracic wall presenting as a parietal tumefaction of the posterior thoracic or paravertebral wall, neurological symptoms, and respiratory involvement. Additionally, we evaluated physical examination parameters such as general examination, thoracic floor assessment, and neurological and abdominal examinations.The radiological assessment included a chest X-ray, X-ray of the spine, coastal grid, thoracic, soft tissue, and abdominal ultrasound, CT-scan, Magnetic Resonance Imaging (MRI), and other radiological examinations such as medullary arteriography. Biological tests were carried out, including hydatid serology and a blood count to check for hypereosinophilia.<b>Operative data</b>: We specified the therapeutic management elements: anesthesia, surgical position, surgical approach, per-operative findings, and surgical procedure: which we have divided into three stages: surgical resection of part of the chest wall (including ribs, vertebrae, and/or muscles), surgical spinal stabilization: anterior by a bone marrow transplant or by osteosynthesis with a fixation material and conservative surgical procedure when the operation is performed only on the cystic lesion without ablating a part of the thoracic wall. We identified the used scolicidal solution (hydrogen peroxide, povidone-iodine, hypertonic saline), the protection of the operating field (use of soaked gauze in scolicidal solution to protect pleura and soft tissues for possible scolex dissemination), and we mentioned per-operative complications.<b>Postoperative data</b>: We recorded the duration of drainage and hospital stay, immediate postoperative course: simple or complicated, and late complications. Late course: was assessed by clinical examination (neurological by ASIA score to evaluate motor skills and sensitivity) and postoperative sequelae. During the follow-up period, every hydatid recurrence was recorded (time, treatment modalities, surgical treatment (approach, procedure, number of repeat surgeries, evolution after treatment of recurrences). Antiparasitic medical treatment was noted (molecule and length of treatment) and the pathological examination. We identified the mortality (frequency, causes, delay). We defined lost to follow-up patients as those who missed outpatient visits for more than three consecutive years.