Objective To evaluate the cl inical outcomes of anterior decompression, bone graft and internal fixation in treating fourth lumbar burst fractures with il iac fenestration. Methods From February 2001 to May 2006, 8 cases of fourth lumbar burst fractures were treated by anterior decompression, correction, reduction, il iac autograft, Z-plate internal fixation with il iac fenestration. Of them, there were 7 males and 1 female, aging 24-46 years with an average of 29.3 years, including 3 cases of Denis type A and 5 cases of Denis type B. The decompression, intervertebral height were compared betweenpreoperation and postoperation by CT scanning. According to Frankel assessment for neurological status, 2 cases were at grade C, 5 at grade D and 1 at grade E before operation. Four cases had different degrees of disturbance of sphincter. Time from injury to operation was 8 hours to 11 days. The preoperative height of the anterior border of the L4 vertebral body was (13.8 ± 2.3) mm, the Cobb angel of fractured vertebral body was (13.2 ± 2.5)°, the vertebral canal sagittal diameter of L4 was (10.6 ± 3.5) mm. The bone graft volume was (7.5 ± 1.3) cm3 during operation. Results Operations were performed successfully. The mean operative time was (142 ± 25) minutes and the mean amount of blood loss was (436 ± 39) mL. The incisions obtained heal ing by first intention after operation. Two cases suffered donor site pain and recevied no treatment. The follow-up time of 8 cases was from 21 months to 52 months (mean 24.5 months). At one week after operation, the height of the anterior border of the L4 vertebral body was (32.5 ± 2.6) mm, the Cobb angel of fractured vertebral body was (6.8 ± 3.7)°, and the vertebral canal sagittal diameter of L4 was (19.8 ± 5.1) mm, showing significant difference when compared with those of preoperation (P lt; 0.01). At the final follow-up, the results showed that the pressure was reduced sufficiently, all autograft fused well, the neurological status improved at Frankel grade from C to D in 1 patient, from D to E in 3 patients, but the others had no improvement. In 4 patients who had disturbance of sphincter, 3 restored to normal and 1 was better off. Conclusion Cl inical outcomes of anterior surgery for fourth lumbar burst fractures with il iac fenestration are satisfactory. It can facil icate operation, reduce the pressure sufficiently, maintenance intervertebral height and recover the neurological function.
Objective To review the primary tracker fixation strategies and associated complications in robot-assisted total knee arthroplasty (RA-TKA), evaluate their respective advantages, limitations, and clinical outcomes, and provide evidence-based references for clinical practice. Methods A comprehensive review of the current literature regarding tracker fixation techniques and related complications in RA-TKA was conducted. The analysis primarily focused on key procedural variables, including the depth of pin penetration (unicortical versus bicortical) and the insertion trajectory (intra-incisional versus independent/percutaneous incision). Results Current research predominantly centers on two parameters: the number of cortices penetrated by the fixation pins and the spatial relationship between the pin insertion site and the primary surgical approach. Existing evidence indicates that unicortical fixation at the medial epicondylar region of the femur, combined with an independent, small-incision unicortical fixation on the tibial side, yields superior mechanical stability, minimizes intraoperative tracker micro-motion, and demonstrates an excellent safety profile. The overall incidence of tracker-related complications remains low; these primarily include localized pain, soft tissue irritation, pin-tract infections, and, rarely, iatrogenic fractures. The majority of these complications have favorable prognoses. Conclusion A standardized clinical consensus on tracker fixation protocols in RA-TKA has yet to be established. In clinical practice, surgeons should employ individualized fixation strategies tailored to the patient’s bone quality, local anatomy, and surgical expertise. Prioritizing minimally invasive, highly stable, and low-risk fixation options is crucial to mitigating iatrogenic injury without compromising surgical precision.
