The rod link reducer has a basic “H” shape that rigidly links and locks the provisional rods. The rod link reducer is a universal connecting link to provide a three-dimensional correction of the spinal deformity. It allows attachment to the rod at any orientation in the coronal, sagittal, and transverse planes so as to make a compression, distraction, derotation, and translation method.

The relative tools include (1) a screwdriver which is specially designed for the double-decker screw fixation (Fig. 13.4); (2) a long-arm tube wrench which is for a breakaway of the top-loading and side-loading apertures of the screw (Fig. 13.2); and (3) a final rod insertion wrench which is designed for the easy insertion of the final rod (Fig. 13.5).

The animal surgery protocol was approved by the Institutional Animal Care and Use Committee. The 1-month-old pigs (5–8 kg) underwent general anesthesia with 6 mg/kg Telazol (Fort Dodge Animal Health, Fort Dodge, IA) administered intramuscularly. All received antibiotics preoperatively (35 mg/kg cephaxolin intravenously) and postoperatively (3 mg/kg ceftiofur intramuscularly twice a day for 3 days). The animals were placed in the left lateral decub itus position with the right side up. A curvilinear incision was made over the 15th rib (the most distal rib) for the anterior staple tethering from T14, T15 to L1. Following the incision of the muscle layers, a subperiosteal dissection was performed circumferentially around the rib. Medially a self-retaining retractor was near the costochondral junction. Following the incision of the costochondral junction and removing the 15th rib, the retroperitoneal fat was identified, which allowed gaining entrance into the retroperitoneal space. The abdominal contents were then bluntly dissected off the undersurface of the diaphragm and abdominal wall. The diaphragm, which was kept intact, ended on the body of the T14. The anterior edge of the psoas was sharply dissected off the spine and retracted posteriorly. The distal part of the vertebral body of T14, the disc of T14-15, the body of T15, the disc of T15-L1, and the body of L1 were exposed. The segmental vessels were then ligated individually with silk sutures. Thorough annulotomies and discectomies were performed at the two motion segments of the T14-T15 and the T15-L1. A Cobb elevator was used to sharply dissect the cartilaginous end plate off the bony end plate to allow complete removal as one segment without creating significant osseous end plate bleeding. A custom staple was placed over the level of the T14-15 and the level of the T15-L1 laterally, respectively. A longer custom staple was placed between the T14 and L1 more anteriorly (Fig. 13.14). The disc spaces of the T14-15 and T15-L1 were filled with the rib autograft. The rib was approximated by using a large #1 absorbable suture, and the periosteum of the resected rib was sutured. The abdominal muscle was closed in layers.

Analgesics (1.5 mg/kg flunixin meglumine) were administered intramuscularly twice a day for 3 days postoperatively. No postoperative immobilization was used. The animals were radiographed to assess the curve in the coronal and sagittal planes at immediate postoperatively and 1-month interval for 4 months. All animals survived without neurologic complications and remained normal and healthy for 4 months. An average 60° (51°–75°) angular kyphosis was created between the T14 and L1 in all 5 animals at 4-month follow-up (Fig. 13.15).