Risk Factors for Postsurgical Foot Complaints One Year Following Degenerative Lumbar Spinal Surgery

Abstract

MiniPostsurgical foot complaints occurred frequently in 853 degenerative lumbar surgeries (prevalence, 20.6%; n=176). Risk factor analysis showed that the incidence of postsurgical foot complaint was significantly higher in patients with preoperative foot symptoms (adjusted odds ratio, 5.532) and in those with preoperative sensory deficits on the leg (adjusted odds ratio, 1.904). Study Design.Retrospective.Objective.To investigate the prevalence and risk factors of postsurgical foot complaints (PFCs) following spinal surgery by using a modified pain drawing (PD) instrument.Summary of Background Data.Although many patients report nonspecific foot symptoms with various clinical presentation, there is not a well defined diagnostic criterion. PDs are essential for measuring spinal surgery outcomes. We created a modified patient-physician communication-based PD instrument to overcome the limitations of the previous system.Methods.We included 853 consecutive patients who underwent decompression with or without fusion. PFCs were defined as sensory foot symptoms, including ambiguous sensations that were not clearly due to spinal pathology. Patients who complained of postoperative foot symptoms at more than two consecutive visits were assigned to the PFC group. The remaining patients were assigned to the asymptomatic group. We collected medical records using our PD instrument and compared variables between the two groups.Results.In total, 176 (20.6%) of the 853 patients had PFCs. The duration of preoperative leg pain was significantly longer in the PFC group than in the asymptomatic group (2.8 vs. 2.2 years; P=0.048). The proportions of preoperative foot symptoms (82.9% vs. 43.3%) and sensory deficits on the leg (48.6% vs. 27%) were significantly greater in the PFC group than in the asymptomatic group (P<0.001). Multivariable logistic regression analysis revealed two independent risk factors: the presence of preoperative foot symptoms (adjusted odds ratio, 5.532) and preoperative sensory deficits on the leg (adjusted odds ratio, 1.904).Conclusion.PFCs occurred frequently after degenerative lumbar spinal surgery (prevalence, 20.6%). Based on our data using PD instrument, it can help reduce the incidence of PFCs if patients are informed and educated that preoperatively existing foot symptom and sensory deficits on the leg are significant risk factors for PFC development.Level of Evidence: 4