Redefining the Classification for Bertolotti Syndrome: Anatomical Findings in Lumbosacral Transitional Vertebrae Guide Treatment Selection

Objective: We present the Jenkins classification for Bertolotti syndrome or symptomatic lumbosacral transitional vertebra (LSTV) and compare this with the existing Castellvi classification for patients presenting for treatment. Methods: We performed a retrospective cohort study of 150 new patients presenting for treatment of back, hip, groin, and/or leg pain from July 2012 through February 2022. Using magnetic resonance imaging, computed tomography, and radiography, the patients with a radiographic finding of LSTV, an appropriate clinical presentation, and identification of LSTV as the primary pain generator via diagnostic injections were diagnosed with Bertolotti syndrome. Patients for whom conservative treatment had failed and who underwent surgery to address their LSTV were included in the present study. Results: The Castellvi classification excludes 2 types of anatomic variants: the prominent anatomic side and the potential transverse process and iliac crest contact. Of 150 patients with transitional anatomy, 103 (69%) were identified with Bertolotti syndrome using the Jenkins classification and received surgery (46 men [45%] and 57 women [55%]). Of the 103 patients, 90 (87%) underwent minimally invasive surgery. The patients presented with pain localized to the back (n = 101; 98%), leg (n = 79; 77%), hip (n = 51; 49%), and buttock (n = 52; 50%). Only 84 of the Jenkins classification patients (82%) met any of the Castellvi criteria. All 19 patients for whom the Castellvi classification failed had had type 1 anatomy using the Jenkins system and underwent surgery (decompression, n = 16 [84%]; fusion, n = 1 [5%]; fusion plus decompression, n = 2 [11%]). Of these 19 patients, 17 (89%) had improved pain scores. The 19 patients exclusively diagnosed via the Jenkins classification had no significant differences in improved pain compared with those diagnosed using the Castellvi classification. Conclusions: The Jenkins classification improves on the prior Castellvi classification to more comprehensively describe the functional anatomy, identify uncaptured anatomy, and better predict optimal surgical procedures to treat those with Bertolotti syndrome.