Birth weight and incidence of surgical obstetric brachial plexus injury.

Objectives: (1) To analyze the birth weight of obstetric brachial plexus injury (OBPI) patients requiring one or more reconstructive surgeries and (2) to analyze whether there is any difference in the severity of the injury, and the outcome of the surgery between the macrosomic and nonmacrosomic OBPI patients.

Study Design: An observational cohort study was performed on 100 consecutive patients treated with surgery at the Texas Nerve and Paralysis Institute. Ninety of the 100 patients underwent the modified Quad surgery, which improves the shoulder abduction and overall shoulder function. All OBPI patients in our study were assessed preoperatively and postoperatively by evaluating video recordings of active shoulder abduction.

Results: Using a 4000 g definition of macrosomia, 52% of patients would be considered macrosomic, and using a 4500 g definition of macrosomia, 18% of patients are considered macrosomic in our study. Permanent injury occurs also in average-birth-weight children.

Conclusions: A significant percentage (48%-82% depending on definition of macrosomia) of OBPI patients requiring major reconstructive surgery had birth weights which would put them in the "normal" birth weight category. In addition, we found that there was no significant difference in the severity of the injury, and the outcome of the modified Quad surgical procedure between macrosomic and nonmacrosomic OBPI patients. However, there was a significant improvement in shoulder movement in both macrosomic and nonmacrosomic patients after modified Quad surgery.