Does the Extent of Rod Bending and Actual Lumbar Lordosis Mismatch Affect Quality of Life?

To evaluate any mismatch between rod bending and actual lordosis during posterior lumbar instrumentation and its effects on the quality of life (QOL) of patients.

Patient records for posterior lumbar fusion in 2018-2023 were retrospectively reviewed. The radiologic parameters consisted of pelvic incidence, sacral slope, L1S1 lumbar lordosis, lumbosacral angle, the distance between the posterior wall of the vertebra and the rod, lordosis of the rod. The postoperative QOL of patients was assessed using Oswestry Disability Index. The patients were grouped postoperative into Group-1 (minimal/moderate disability) and Group-2 (severe disability/crippled/bed bound).

Total of 133 patients were included; 99 women, 34 men. The difference was significant for patients with diabetes to be presented in the more disabled Group-2. The distance between the posterior vertebral wall and the rod was found to be short in Group-2. Preoperative and postoperative sagittal lumbar Cobb angles were significantly higher in Group-2. The changing degree of pain was found to score high in Group-2. The postoperative visual analog scale was high in Group-2. The difference between the preoperative and postoperative lumbar sagittal Cobb and rod Cobb-angles was found to be high in Group-2.

The results of our study confirm the importance of considering the preoperative actual lumbar lordosis during bending and maintaining it as much as possible. To our knowledge, this is the first study that evaluated the effect of rod bending on quality of life (QOL) and supports that this might be affected in case of any mismatches.