Effectiveness of percutaneous screws for treatment of degenerative lumbar low back pain

The purpose of this retrospective observational study was to demonstrate the efficacy of a percutaneous screws system in the treatment of lumbar pain caused by high-level disc degeneration combined with facet joint hypertrophy and canal stenosis especially in the L5-S1 levels.

Thirty-eight patients (25 males, 13 females, mean age 63 years) with lumbar pain and/or neuralgia-claudication were treated with interpeduncular dynamic screws. Diagnosis was based on clinical\medical history evaluation and X-ray, CT, and MR examinations. All patients completed the visual analogic scale (VAS) for evaluation of clinical efficacy and pain measurement both before and after (1 month and after 2 years) the procedure. Patients also were given the Oswestry disability index (ODI) before and after treatment. The area of the neuroforamina also was measured.

Thirty-eight intervertebral spaces were treated. The VAS pain scale showed a reduction of pain symptoms at 1 month and after 2 years (VAS pre 8.7 ± 1.1; after 1 month 5.1 ± 2.2; after 2 years 6.5 ± 2.1; p = 0.001). ODI also showed improvement (pre 56.7 ± 18.6 %; after 1 month: 31.9 ± 26.3%; after 2 years: 42 ± 24.2 %, p = 0.001). The study showed a widening of the neuroforaminal area of 15.5 % in the right neuroforamen and 17 % in the left ones (right foraminal area pre 0.94 mm(2), post 1.08 mm(2); left foramina area pre 0.95 mm(2), post 1.11 mm(2)). In addition, the spinal canal area displayed a statistically significant reduction (pre = 1.97 and post = 2.23; p < 0.0001).

Our study indicates that patients treated with dynamic screws have VAS pain reduction as well as ODI improvement. Moreover, we found a statistically significant widening of the neuroforaminal area.