Does transforaminal lumbar interbody fusion produce leg pain?—Results from a RCT

Background: Transforaminal lumbar interbody fusion (TLIF) is presently the most used method to achieve lumbar interbody fusion worldwide. The special preparation and cage insertion imply a risk of an undesirable side effect in the form of residual neurogenic pain. This issue has not been investigated prior in a randomized clinical trial (RCT) set up.Aim: To test whether TLIFs had a higher incidence of leg pain in comparison to a common instrumented posterolateral fusion (PLF) and to test whether a higher occurrence of leg pain on the ipsilateral side in the TLIF group was present.Methods: One hundred patients included in a RCT comparing TLIF and PLF fulfilled pain drawings and numeric rating scale (NRS) scale from 0 to 10 preoperatively, after 1 year, and after 2 years. Difference in pain appearance, type, localization, and intensity was compared between groups.Results: A slightly higher number of patients in the TLIF group reported leg pain at 2 years follow-up: no leg pain, 47% (PLF) and 37% (TLIF); unilateral leg pain, 31% (PLF) and 25% (TLIF); bilateral leg pain, 22% (PLF) and 37% (TLIF), p = 0.270. Numbness and pins and needles on the anterior aspect of the lower leg were marked by 10% and 12% of TLIF patients compared to 6% and 4% in PLF patients p = 0.498/0.197. The ipsilateral side of cage insertion in the TLIF group was not a place for new leg pain compared to the contralateral side.Conclusion: The special surgical preparation used in TLIFs does not result in the development of new ipsilateral leg pain. However, a higher percentage of the patients in the TLIF group had new leg pain in comparison to PLF after 2 years.