Here's more you can do to help alleviate symptoms and even heal yourself of the problem. I've healed carpel tunnel syndrome, trigger finger, and alleviated thoracic outlet syndrome with this therapy. Get yourself a gyro exercise ball. Power Ball or Dyna-Bee are a couple brand names. These syndromes and nerve conditions or nerve impingements are repetitive use injuries. When you keep working a joint in one back and forth motion, or subject a joint to much vibration while in a limited range of motion, such as we do daily, and neglect to work and build the stabilizer muscles that surround and help protect the joint from injury, you open yourself up to repetitive use injuries. Stabilizing the joint, allows the parts to align properly and track right. When things don't track right you get cartilage rubbing, or even bone on bone once the cartilage is eroded away, swelling of and damage to the sheaths that tendons ride in, inflammation, and things like the carpel and cubital tunnel swell and press on the nerve, etc. When tracking right as it was made to do, if the joint is well supported, with no laxity in it, you have lubricated parts that are meant to glide on each other taking the strain better. Do yourself a favor and get a gyro ball exerciser, use it for at least two weeks and you will see the difference, and experience some improvement. Your grip strength will improve, pain and numbness will subside, and you should be able to protect yourself from further injury. As well, work on your core strength. Core strength is vital for protecting your extremities from injury believe it or not. It's the ole knee bone connected to the thigh bone thing. Everything is connected and relates to everything else. Keep good posture while trimming, and also stay well hydrated to help prevent this from worsening. I would suggest getting a shorter trimmer too. Redmax trimmers are longer than many others and cause all but a taller person to have to hold them a bit higher in most situations, which strains and stresses the thoracic outlet whre your nerves that serve the arms exit the spinal column. That can lead to imflammation which pinches the nerves leading down the arm to the hand. Other therapy that will help is exercising on a speed bag. That will build supporting muscles and help stabilize the thoracic outlet area as well as the arm's shoulder, elbow and hand joints. There are exercises you can do with the Power Ball that will also work those muscles and strengthen the support of arm joints. Look up thoracic outlet and find some of the prescribed therapy stretches and exercises for that. This will all lend toward improving joint stability, reduce joint laxity, improving strength and support throughout your full range of motion in the joints affected, and in turn lessen the repetitive injury risk from the rubbing created by misalignment of the gliding parts of the joint.