Differential approach to pectus excavatum corrective surgery in children

Abstract

Pectus excavatum (PE) is the most common defect – it occurs in 0.1–0.8% of the population. This defect is characterized by changes in the cardiorespiratory system, induction of concomitant spinal deformities, severe psychological problems. Nuss surgery and most of its modifications doesn’t provide good results in the treatment of atypical anatomical variants of deformity; it is characterized by displacement and eruption of plates, chronic postoperative pain syndrome, deformity of the ribs, which encourages the search for ways to solve these problems.

Purpose – to improve treatment results in patients with various forms of PE by introducing their own differentiated options for Nuss surgery and choosing the optimal size of fixation plates; to analyze the results of treatment.

Materials and methods. H. J. Park classification has been used. Variants of Nuss surgery have been developed for the following types of IIA1; IIA2; IIA3; IIB, IIC. All surgeries begin with a free extension of the anterior chest wall to the physiological position with ligatures imposed on the sternum’s lower third and ribs. Horizontal plate fixation has been used in IIA1, IIA2, IIA3 types, and in IIB and II C types – its oblique fixation with a lower location of the end of the plate on depressed side. In both versions plate stabilizers are rigidly fixed to 2 (sometimes 3) ribs on both sides under the bones, and in IIB and II C types the plate stabilizer is fixed ventrally at the depressed side and dorsally at the bulging side. For surgical treatment of wide and widened deformation types we use two plates (IB, IIA2, IIA3); one plate is used for treatment of IA, IIA1, IIB, IIC deformations. In the case of the common version of the IIC – two plates. When installing two plates, the shorter upper plate is installed according to Pilegaard at IB, IIA2; standard length – with IIA3 and common version of IIC. We’ve done a mathematical modeling of the correcting plate functioning as a monolithic arched structure with rigidly fixed ends with the determination of the optimal plate width at a thickness of 2.2 mm. Also we’ve analyzed surgical treatment of 55 patients with PE operated in 2018–2020 (ІА – 25; ІВ – 6; ІІА1 – 7; ІІА2 – 3; ІІА3 – 2; ІІВ – 6; ІІС – 4).

Results. Excellent and good cosmetic and functional results were revealed. Postoperative complications – 4 (7.3%). Two postoperative local asymmetric keel-like deformations were noted: one for each in treatment of IIB and IIC (successful treatment is carried out in an individual dynamic compression brace system). In one case, simple pneumothorax was diagnosed, and in another – eruption of one of the two corrective plates. Practical recommendations for determining the optimal plate width at its length of 280 mm and less – 12 mm; 290–300 mm – 13 mm; 310–320 mm – 14 mm; 330–340 mm – 15 mm; 350–360 mm – 16 mm. One month after the operation, 26 patients were surveyed according to the NRSP scale and the following results were obtained: among the operated patients with II degree of deformity: 1 point – 50.0% of patients, 2 points – 25% of patients, 0 points – 25.0% of patients (mean score – 1.0); among patients with III degree of deformity 1 point – 25% of patients; 2 points – 50%, patients 3 points – 12.5% of patients; 0 points – 12.5%, average score – 1.63. There was no chronic postoperative pain.

Conclusions. Key to proposed differential approach in the PE treatment is careful planning of the operation (correct selection of the number of plates, their size, method of installation and fixation depending on the PE anatomical variant). This allows to achieve good and excellent cosmetic and functional results; minimize the number of postoperative complications.

The research was carried out in accordance with the principles of the Helsinki declaration. The study protocol was approved by the Local ethics committee of all participating institutions. The informed consent of the patient was obtained for conducting the studies.

No conflict of interest was declared by the authors.