User's Manual

Information for Patients
Precision Spectra™ System Information for Patients
90668560-01 Rev B 4 of 32
leg pain, pain when walking, standing pain, pain’s effect on overall lifestyle, and the total analog scale
scores were signifi cantly improved from baseline. In this study, 25% of the implanted patients had
greater than 50% improvement in pain rating.
In addition, 3 patients from this study had their stimulators repositioned due to pain at the original
location. Three patients had reoperations to adjust lead position; 1 patient required 2 reoperations,
1 patient had the device removed due to infection and later to have a new device implanted.
A diabetic patient had skin problems which required device removal; a new device was later
implanted. Two patients had the device removed due to unsatisfactory pain relief.
The prospective study performed by Villavicencio et al. 2000 included 41 patients with pain of various
etiologies. The majority of the patients, 24 (59%), had Failed Back Surgery Syndrome (FBSS),
7 (17%) had Complex Regional Pain Syndrome (CRPS I and II), 4 (10%) had neuropathic pain
syndrome, and 6 (15%) were diagnosed as stroke or other. Patients underwent an initial trial period
for SCS with temporary leads. If the trial resulted in greater than 50% reduction in the patient’s pain,
as measured by the VAS, the patient was implanted with a SCS system. In this study, 27/41 patients,
66%, had permanent implants. All patients were examined after 6 weeks. Pain measurements
were assessed at 3-6 month intervals for the fi rst year and annually thereafter. The median long-
term follow-up was 34 months. A total of 24/27 (89%), reported greater than 50% reduction in pain.