Instruments and associated methods are disclosed for treating joints, and particularly bone tissue. One of these instruments may be a positioning instrument for controlled delivery of a device to a target site of the bone tissue being treated. The positioning instrument may comprise a main body extending at one end into an indicator probe for visual determination of a target site of a bone to be treated, and at an opposite end into a handle. A rail extends from the main body. The instrument also includes an alignment guide having a device portal for insertion of a device therethrough, the alignment guide being detachable and movable along a length of the rail. The device may comprise an implant insertion tool, an injection catheter, a cavity creation tool such as a bone drill, for example, or the device may be an implantable device.