Evaluation of pectus bar position and osseous bone formation

Area of Science:

• Pediatric surgery
• Thoracic surgery
• Surgical outcomes

Background:

• Minimally invasive repair using substernal bars is a common treatment for pectus excavatum (PE).
• Bars are typically removed after approximately two years.
• Intense bone formation (BF) around removed bars has been observed, prompting further investigation.

Purpose of the Study:

• To investigate the relationship between bar placement (subcutaneous vs. submuscular) and bone formation (BF) during pectus excavatum (PE) repair bar removal.
• To identify factors influencing bone formation and surgical outcomes at the time of bar removal.

Main Methods:

• Retrospective review of 36 pediatric patients undergoing bar removal for PE repair since 1998.
• Analysis of bar insertion position (subcutaneous [SC] vs. submuscular [SM]), bone formation (radiographic and at removal), operating time, and estimated blood loss (EBL).

Main Results:

• Submuscular (SM) placement was associated with significantly higher rates of bone formation (BF) both radiographically (15/16 SM vs. 3/11 SC) and at removal (19/20 SM vs. 1/16 SC) (P <.001).
• SM placement also resulted in longer operating times (30.2 min vs. 15.6 min, P <.01) and a trend towards higher EBL (18.3 mL vs. 8.8 mL).
• No significant differences were found in the duration the bar was in place or patient age at insertion/removal between groups.

Conclusions:

• Bar positioning is a critical factor in pectus excavatum (PE) repair outcomes.
• Submuscular (SM) bar placement is strongly associated with increased bone formation (BF), longer operating times, and higher blood loss during bar removal.
• Subcutaneous (SC) placement, avoiding fascial violation, is recommended to minimize these adverse effects.