Pre-shaping is a surgical technique proposed by Dr. Wenlin Wang, specifically designed for patients with rigid chest wall bones that cannot easily accommodate direct bar shaping. This technique has become an essential step in the correction of chest wall deformities, playing a crucial role in determining the success of surgery.

The difficulty and risks of chest wall deformity correction are closely tied to the rigidity of the patient’s skeleton. In younger, prepubescent patients, bones are relatively pliable, allowing surgeons to correct the deformity using techniques like the Nuss procedure, where the bars directly elevate or compress the bones to achieve a desired chest contour. However, in adult patients, bones become stiffer with age, making them more resistant to manipulation. In severe cases, the bone rigidity can exceed the strength of the bars, posing additional challenges. For patients over the age of 45, the situation is further complicated not only by bone rigidity but also by its increased fragility, which raises the risk of fracture during direct shaping attempts with bars.

Fortunately, Pre-shaping offers an effective way to address these issues. In simple terms, this technique involves applying external force to the deformed areas using specialized instruments and methods to adjust the thoracic skeleton to a relatively normal appearance. The primary goal is to release stress in the deformed areas prior to shaping with bars, thereby paving the way for smoother and safer correction. For example, in pectus excavatum surgery for adults and elderly patients, a surgical retractor can be used to lift the sunken bony structure and complete the pre-shaping. For patients with acute angle deformity—a specific localized deformity where severe protrusion or depression creates sharp angles in the chest wall—pre-shaping may involve removing sections of the deformed bones. This step helps relieve localized stress, preventing complications such as fracture, deformation of the bars, or even bar breakage during the correction process.

Clinical practice has demonstrated that pre-shaping not only significantly reduces the difficulty and risks of chest wall deformity surgery but also greatly enhances the corrective outcomes, ensuring that patients can receive safer and more effective treatment.