Hi, Firstly, there is no relationship between dominant side or carpal tunnel. Carpal tunnel syndrome can occur on non-dominant side also. Pain in left upper torso may arouse from cervical roots or is referred from visceral organs, but we can relate the upper torso pain with the left wrist pain as both can arise from affection of cervical nerve roots. As far as your knee instability is concerned it appears to be a separate affliction not related to other pain though there are meagre chances of a soft tissue disorder that may be a common pathology for all of them. You need to have a thorough clinical examination along with appropriate investigations to reach a diagnosis. Take care. Hope I have answered your question. Let me know if I can assist you further. Regards, Dr. Rohan Shanker Tiwari, Orthopedic Surgeon