If surgery is contemplated regarding cervical stenosis and an ACDF is recommended, there is a difference between a two level and three level biomechanically. There is more stress on a three level fusion. Also, the type of graft and precision of placement makes a difference in time to solid incorporation of the grafts. The level of participation in biking and skiing also makes a difference.
Regarding the level of participation, are you a road biker or mountain biker? There is less potential load and motion that needs to be dissipated in road biking than in mountain biking. If you rode well maintained gravel roads as a mountain biker rather than tough rocky or root encrusted single track, there is a difference in loading of the cervical spine. The potential for falls and endos increases with greater risk taking while mountain biking. This is the same for skiing. Steep, rough terrain, bumps and crud snow are more risky than groomed slopes. What is your skiing level and what terrain do you like to ski?
Regarding the grafts used, there are three choices, autograft, allograft and Peek cages with a bone substitute filler. Autograft is bone from your own pelvis. Allograft is bone from a cadaver and Peek cages are plastic inserts with allograft filler. The fastest and most complete incorporation is with autograft but this requires a small hip incision. Allograft can be from multiple sources, a pelvis, fibula or calcaneous bone. Each has difference times to incorporation with the pelvis bone incorporating the fastest.
Typically in my practice, you can ride a stationary bicycle in the upright or recumbent position within three days of surgery. You can be on the road within 8 weeks and on single-track in 9-10 weeks depending upon the appearance of the X-ray. Skiing is allowed typically within 8-12 weeks.
Donald Corenman, MD, DC is a highly-regarded spine surgeon, considered an expert in the area of neck and back pain. Trained as both a Medical Doctor and Doctor of Chiropractic, Dr. Corenman earned academic appointments as Clinical Assistant Professor and Assistant Professor of Orthopaedic Surgery at the University of Colorado Health Sciences Center, and his research on spine surgery and rehabilitation has resulted in the publication of multiple peer-reviewed articles and two books.