Complication Profile of Lateral Lumbar Interbody Fusion (LLIF): Navigating the Risks of a Minimally Invasive Approach

Minimally invasive spinal surgery (MISS) reduces morbidity while decompressing the neural structures. Lateral lumbar interbody fusion (LLIF) is a MISS procedure with unique complications due to psoas muscle and lumbar plexus manipulation, including nerve injuries, pseudohernias, hematomas, femoral nerve palsies, and retrograde ejaculation. We retrospectively reviewed LLIF procedures (2014–2022) at our center, analyzing demographics, operative details, and complications. Among 546 patients (976 levels), 375 (632 levels) had ≥6 months follow-up. Mean age: 62.9±10.1 years; BMI: 30.5±5.7 kg/m². Overall complication rate: 21.9%. Neurological complications: thigh paresthesia (13.3%), transient leg weakness (11.2%), knee extension limitation (1.1%), and hip flexion weakness (1.3%). Surgical complications included psoas hematoma (0.5%) and pseudohernia (0.75%). Multilevel LLIF significantly increased complications (p=0.008), rising from 20.5% (single-level) to 57% (four-level, p=0.001). LLIF presents a distinct complication profile, particularly transient neurological deficits. While effective for single-level cases, multilevel LLIF significantly raises complication rates.