Berserker is like so many guy's who ask questions here. They only give half of the story as to the cause of the problem; arm in a cast, pins inserted, tendon/joint, muscle damage, disease tissue, arm caught in a cookie jar, etc, etc, etc..How long a period the bicep not used, any doctor orders, going through rehab, etc, etc, etc.. Most guy's want to help here but you do need something to go on by giving the root cause of the bicep problem. Let's me take a shot anyway, for what it's worth or not worth.
Actually incorporating the biceps with back exercises (rows, pulldowns, etc) , as a lifting unit can help greatly in getting the bicep back to normal. Lightly at first and probably with DB's or single pulling cable movements. You may feel weak at the beginning but the body will adapt, fairly fast, as a part of the lifting process. Start a back workout with some of the above exercises and add weight as you advance workout from workout.
As Bluto suggest, the Nautilus pullover machine would be the prime back builder in anyone's training. Or any of the other back/lat machines that allow the elbows to lead the exercise (where the elbows are resting on pads...no involvement with the biceps). If your gym has such equipment, than great.
There are also wide straps the fit around the elbows for pulling movements. Usually used with sitting cable exercises. Depending on the make of the straps, some require a light grip and some don't. Some of these straps can be used for overhead pulldowns and even chins. These are great lat/back builder's because of taking out the weaker link, the bicep's themselves. You can also do reverse pec deck exercises for the posterior delt/upper back. Good Luck.
