Spondylolisthesis is Common, Early, and Severe in Loeys-Dietz Syndrome

Background: We studied the prevalence and treatment outcomes of spondylolisthesis in patients with Loeys-Dietz syndrome (LDS). Methods: Clinical data and lumbosacral imaging of 138 patients with LDS were reviewed. Spondylolisthesis (L4-L5 or L5-S1) and spondylolysis were characterized by multimodal imaging and correlated with clinical data. Treatments and outcomes were characterized for patients with spondylolisthesis. Associations were determined using the Fisher exact, Mann-Whitney, and Student t tests (&agr;=0.05). Results: Twenty-four patients (17%) had spondylolysis and 23 (17%) had spondylolisthesis. Median age at spondylolisthesis diagnosis was 11 (interquartile range, 9.5) years. In patients in whom measurement was possible (n=20), mean (±SD) slip was 48% (±35%). Nineteen patients had L5-S1 slip and 4 had L4-L5 slip. Of the patients with spondylolisthesis, 5 had no evidence of spondylolysis; of those with spondylolysis, all but 6 had spondylolisthesis. Eleven patients with spondylolisthesis underwent posterior spinal fusion (PSF) to treat slip progression, pain, and/or neurological deficit. Spondylolisthesis recurred in 1 patient who underwent PSF with bone graft arthrodesis alone (no instrumentation). The other 10 patients underwent PSF with instrumentation and fusion. Three patients additionally underwent Bohlman interbody fusion. Two patients developed implant failure. S2 fixation was performed at revision to achieve fusion in these patients. Mean Meyerding grade improved in patients who underwent arthrodesis, from 3.9 (±1.2) to 1.9 (±1.3) (P=0.002). Complications were 2 cerebrospinal fluid leaks, 2 transient postoperative paresthesias, and 1 case each of pseudarthrosis at S1-S2, wound dehiscence, and transient urinary incontinence. No significant associations between LDS type and lumbosacral abnormalities were found. Conclusions: High-grade spondylolisthesis is common in LDS and usually associated with spondylolysis. Patients requiring surgery for spondylolisthesis present during childhood and do well after instrumented PSF. Interbody fusion and stabilization of S1 and S2 can prevent physeal deformation. LDS should be considered in patients with high-grade spondylolisthesis. Patients with LDS should be monitored for spondylolisthesis and spondylolysis starting when they are young. Level of Evidence: Level IV—retrospective study.