Hi well come to HCM For any bone TB teatment is of longer duration, ie one one and half year. In your sisters case there was a weakness on lt lower leg, suggetive of compression on spinal cord with bone erosion. Pretty advanced stage, its good that it was diagnosed and treatment started other wise she could have paralysed her both lower limbs. She has to take full treatment so long doctor says, has to take injection streptomycin if your doctor has recommeded. Consult spine surgeon if possible. And after completion of treatment even keep regular follow up with Doctor as per his advice. And in case little doubt of recurence contact your doctor immediately. thanks