My neck is always sore and I can crack it quite often which helps alleviate the discomfort. I dont feel its a medical condition but more a lack of strenght and overall conditioing of the nexk muscles. I remeber reading this somewhere and thought this might help?
Lying Isometric Neck Flexion
2 x 60 Secs
Neck Harness Extension
3 - 6 x 20 Reps
Neck Harness Flexions
3 - 6 x 20 Reps
Neck Harness Forward Hold
1 - 3 x 120 Secs
Neck Harness Backward Hold
1 - 3 x 120 Secs