Comparative Study between Medial Rectus Recession and Superior Rectus Transposition to Lateral Rectus with and without Foster Suture in Management of Complete Sixth Nerve Palsy

Background: Complete sixth nerve palsy is a challenging disorder manifested by esotropia and marked limitation of abduction. Surgical management aims to improve ocular alignment and motility.Aim: This study compared the efficacy of medial rectus recession combined with superior rectus transposition (SRT) to lateral rectus, performed with and without Foster's suture, in treating complete sixth nerve palsy.Methods: A prospective study involved 30 eyes diagnosed with complete sixth nerve palsy. Patients were equally divided into two groups: Group A (15 eyes) underwent medial rectus recession and superior rectus transposition to lateral rectus with Foster suture, while Group B (15 eyes) underwent the same procedure without Foster suture.Results: Both groups showed significant postoperative improvement. In Group A, there was a significant reduction in primary angle of deviation compared with preoperative values (p < 0.001). Postoperatively, 60% of patients achieved orthotropia, 26.7% had residual esotropia, and 13.3% developed exotropia. In Group B, a highly significant decrease in the primary angle was also observed (p < 0.001). Postoperative alignment revealed orthotropia in 33.3% of patients, residual esotropia in 60%, and exotropia in 6.7%. Improvement in ocular alignment was greater in Group A.Conclusion: Medial rectus recession combined with superior rectus transposition to lateral rectus, with or without Foster's suture, is effective in improving esotropia and abduction limitation in complete sixth nerve palsy. However, the addition of a Foster suture yields better postoperative alignment, with a higher rate of orthotropia.