Introduction: Despite the long-term use of intramuscular and intraosseous lidocaine trigger point injections (LTPI) in the treatment of patients with low back pain, there have been no studies examining their efficiency in treatment of residual pain after degenerative lumbar spinal stenosis (DLSS) decompression surgery. The purpose of our research is to examine the LTPI efficiency in the treatment of residual lumbar pain after DLSS decompression surgery and to compare the analgesic and recovery effects of intramuscular and intraosseous LTPI administered in the L4–S1 region and in the posterior superior iliac spine (PSIS) after treatment and during four months of follow-up. Materials and Methods: We observed 99 patients (F:50, M:49) aged 42 to 59 years with residual neurological disorders after DLSS decompression surgery. In all patients, the pain syndrome exceeded 6 points on the VAS and averaged 7.2 ± 0.11 points. The control group (n = 21) underwent only pharmacotherapy. In addition to pharmacotherapy, the LTPI group underwent intramuscular LTPI in L4–S1 (n = 20), intramuscular LTPI in the PSIS (n = 19), intraosseous LTPI in L5, S1 (n = 20), and intraosseous LTPI in the PSIS (n = 19). A neurological examination was carried out before treatment, 7 days after completion of treatment, and at the end of the second and fourth months of the follow-up period. Results: In the control group, intramuscular LTPI in L4–S1 subgroup, intramuscular LTPI in PSIS subgroup, intraosseous LTPI in L5, S1 subgroup, and intraosseous LTPI in PSIS subgroup, the severity of pain decreased after treatment by 27.1% (p ≤ 0.05), 41.7% (p ≤ 0.01), 50.7% (p ≤ 0.01), 69% (p ≤ 0.01), and 84.7% (p ≤ 0.01), respectively, and at the end of the second month of follow-up, by 14.3% (p > 1), 29.2% (p ≤ 0.05), 38% (p ≤ 0.01), 53.5% (p ≤ 0.01), and 72.2% (p ≤ 0.01), respectively. Reduction of neurogenic claudication, regression of sensory deficit, increase of daily step activity, and improvement of quality of life after treatment were noted in intramuscular LTPI subgroups by 19.6% (p ≤ 0.05), 36.4 (p ≤ 0.05), 40.3% (p ≤ 0.01), and 21.0% (p ≤ 0.05), respectively, and in interosseous LTPI subgroups by 48.6% (p ≤ 0.01), 67.4% (p ≤ 0.01), 68.3% (p ≤ 0.01), and 46% (p ≤ 0.01), respectively. Conclusions: LTPI is highly effective in the treatment of patients with residual pain after DLSS decompression surgery. High analgesic effect, significant regression of sensory deficits and gait disorders, and remarkable improvement of daily step activity and quality of life are noted not only after the end of LTPI treatment but also continue for at least 2 months after treatment. Intraosseous LTPI is more effective than intramuscular LTPI by 92%, and LTPI in PSIS is more effective than LTPI in L4–S1 by 28.6%.
