Anterior cervical discectomy and fusion (or ACDF) surgery serves to remove herniated or degenerative spinal discs. A discectomy literally “cuts out the disc” anywhere along the spine from the neck to the low back. Along this procedure, different devices can be inserted to restore patient’s motion:
Interbody fusion cage
“Anterior cervical discectomy” has matured into a safe and effective procedure for the treatment of degenerative disc disease. In this procedure a hollow implant can be inserted in the spine to restore physiological disc height, allowing bone growth within and around them to stimulate bone fusion. Interbody fusion cages (or spine cages) have a load-sharing function and stabilize the spine. Traditionally made of PEEK, they are normally used in conjunction with titanium-made screws in patients suffering from spinal instability stenosis or others spinal degenerations.
Metal additive manufacturing improves usual fusion cages by compining the biocompatibility of titanium with the flexibility of plastic PEEK. The porous titanium cage fabricated by SLM could achieve fast bone ingrowth and better osseointegration with a superior mechanical stability than the conventional PEEK cage.
The particular density distributions give to titanium parts the same flexibility as traditional PEEK products, which is customised to be embedded in the spine. The higher strength of titanium allows the integration of inspection windows in the sidewalls of the 3d-printed implants. Thus, bone growth can be evaluated through medical imaging. The geometric freedom and functional integration of additive manufacturing offer a multitude of new options in spinal column reconstruction.
Customised disc prostheses
Instead of a bone graft or fusion cage, an artificial disc device may be inserted into the empty disc space. In select patients, it may be beneficial to preserve motion. It acts as a vertebral spacer to strengthen the spine and can be designed to fit perfectly into the vertebral plate. Both design and spacing dimensions can be adjusted precisely to the patient’s anatomy in accordance with the surgeon’s specifications. With laser-melting, these 3d-printed implants can be manufactured in a “one-shot” process, a solution that gets rid of downstream assembly processes.