At work I managed to cut half way through an extensor tendon on my left hand index finger at the first knuckle. Following surgery to stitch the tendon I now face at least 12 weeks of physio before any lifting re-commences. I’ve already lost 8-9lbs of hard earned muscle in the last 4 weeks, I would welcome any tips on how to maintain muscle mass during this time despite my now limited physical abilties.
You have your right upper extremity and lower extremities with no limitations that you can concentrate on.
Also, I would recommend checking out the following article on ways to train your left upper extremity without the ability to hold onto the weights:
Three Work-Arounds for Physique Success by Nick Tumminello