Howell Chiropractic is a chiropractic clinic located in Davenport, IA. Phone: 5633406612. 7 verified patient outcomes documented on ChiropracticResults.com. Specialties include: Acute low back pain., Chronic low back pain (LBP). Top documented result: 100% reduction in pain. Patient returned to normal activity after treatment. for Acute low back pain. in 1 visit that included PiezoWave and chiropractic adjustment. This clinic's patient outcomes are independently verified and publicly documented.