title: Predictors of improved quality of life and claudication in patients undergoing spinal cord stimulation for critical lower limb ischemia.
abstract: BACKGROUND
  The aim of this study was to determine predictors of improved quality of life and claudication in patients undergoing spinal cord stimulation (SCS) for critical lower limb ischemia.
  
  
  METHODS
  We retrospectively analyzed 101 consecutive patients with few meter claudication and nonhealing ulcer who underwent definitive SCS. These patients were selected among 274 SCS patients treated at our center from 1995 to 2012. All presented with non-reconstructable critical leg ischemia (NR-CLI) and underwent supervised exercise therapy, best medical care and regular ulcers standard or advanced medications for at least 1 month before SCS implantation. We measured self-perceived quality of life using the SF-36 questionnaire. Patients with an improved walking distance of at least 30 meters after SCS had significant improvement on SF-36 questionnaire scores. We considered 30 meters as the cut-off for clinically significant improvement in pain-free walking distance, and we defined this value as functional success. Logistic regression was applied to assess baseline and other patient variables as possible predictors of functional success.
  
  
  RESULTS
  Neither perioperative mortality nor significant complications were found. At a median follow-up of 69 months (range 1-202 months), mortality, major amputation, and minor amputation were 8.9%, 5.9%, and 6.9%, respectively. Functional clinical success was reported in 25.7% of cases. Independent predictors of functional success at univariate analysis included delay between the onset of the ulcer and SCS (P < 0.001) and the pain-free walking distance before SCS (P < 0.002). The only predictive factor of functional success at multivariate analysis was the delay between the onset of ulcer and SCS (median delay in patients with and without functional success was 3 and 15 months, respectively). In particular, comparable to pain-free walking distance before SCS, the success rate decreased by 40% for each month elapsed from onset of ulcer to SCS.
  
  
  CONCLUSIONS
  In our series of patients who underwent SCS, reduced delay between the onset of ulcer and SCS was associated with improved quality of life and walking distance. Larger series are required to confirm these data and to assess clinical implications.
authors.affiliation: Department of Vascular Surgery, Scientific Institute H. San Raffaele, Vita-Salute University School of Medicine, Milan, Italy.
authors.forename: Yamume
authors.initials: Y
authors.lastname: Tshomba
authors.affiliation: Department of Vascular Surgery, Scientific Institute H. San Raffaele, Vita-Salute University School of Medicine, Milan, Italy. Electronic address: daniele.psacharopulo@yahoo.it.
authors.forename: Daniele
authors.initials: D
authors.lastname: Psacharopulo
authors.affiliation: Department of Vascular Surgery, Scientific Institute H. San Raffaele, Vita-Salute University School of Medicine, Milan, Italy.
authors.forename: Serena
authors.initials: S
authors.lastname: Frezza
authors.affiliation: Department of Vascular Surgery, Scientific Institute H. San Raffaele, Vita-Salute University School of Medicine, Milan, Italy.
authors.forename: Enrico Maria
authors.initials: EM
authors.lastname: Marone
authors.affiliation: Department of Vascular Surgery, Scientific Institute H. San Raffaele, Vita-Salute University School of Medicine, Milan, Italy.
authors.forename: Domenico
authors.initials: D
authors.lastname: Astore
authors.affiliation: Department of Vascular Surgery, Scientific Institute H. San Raffaele, Vita-Salute University School of Medicine, Milan, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Chiesa
mesh_terms: D000671:Amputation, Surgical; D005080:Exercise Test; D017079:Exercise Tolerance; D006801:Humans; D007383:Intermittent Claudication / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology / Q000523:psychology / Q000628:therapy*; D007511:Ischemia / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology / Q000523:psychology / Q000628:therapy*; D007871:Leg Ulcer / Q000175:diagnosis / Q000628:therapy; D016015:Logistic Models; D035002:Lower Extremity / Q000098:blood supply*; D015999:Multivariate Analysis; D016017:Odds Ratio; D010147:Pain Measurement; D011788:Quality of Life; D020127:Recovery of Function; D012042:Registries; D012189:Retrospective Studies; D062187:Spinal Cord Stimulation / Q000009:adverse effects / Q000401:mortality; D011795:Surveys and Questionnaires; D013997:Time Factors; D016896:Treatment Outcome; D014945:Wound Healing