A distal portion of a filament is extended beyond the distal end of a needle containing a gripper. A flexible one-way filament retainer with a snagging point is positioned adjacent to the extended filament. The needle with the extended filament and the one-way filament retainer are inserted into a cannula. During partial withdrawal of the needle, the snagging point of the one-way filament retainer hooks or retains the distal portion of the filament, depositing a section of the filament between the snagging point of the one-way filament retainer and the needle. When the needle is re-advanced, the needle pushes open the flexible one-way filament retainer, and the section of the filament is expelled or deposited in tissue. The needle can be rotated; the gripper engages and spirals the expelled filament to burrow into tissue. The method of needle partial withdrawal, re-advancement, rotation and pushing is repeated to pack and fill the tissue with interconnecting spirals of filament.

Intervertebral discs are avascular. Oxygen, nutrients and bicarbonate diffuse from capillaries in cartilaginous endplates into discs to feed and maintain disc cells. As we age, calcified layers form at the endplates, blocking and occluding capillaries. Diffusion zones of oxygen and nutrients in disc become shallow. Cells in mid-layer of the disc suffer chronic anaerobic and starving conditions. Lactic acid is produced. Disc cells die from starvation, causing disc degeneration and forming fissures in annulus. Lactic acid leaks from fissures to the outer annulus of the disc to cause irritation, inflammation and persistent pain. Spirals of filament are implanted into the painful and degenerating disc to draw oxygen, nutrients and bicarbonate from the shallow diffusion zones of the cartilaginous endplates into the mid-layer of the degenerating disc. Oxygen inhibits anaerobic production of lactic acid; nutrients feed disc cells to halt disc degeneration; bicarbonate neutralizes lactic acid in the mid-layer to relieve pain.