Hello, Post-injury of the knee, there is a possibility of the fluid accumulation and also muscle weakness to the extent. Also, to avoid such features post fall I Will advice you to do regular exercise like - ankle toe movements which will help correction of the muscle imbalances and also improve the venous return thereby reducing the swelling. Static quadriceps and static hamstring along with straight leg raise will provide good strength in the muscles of the thigh and avoid joint compression if present any due to muscle weakness. Hope I have answered your query. Let me know if I can assist you further. Regards, Jay Indravadan Patel, Physical Therapist or Physiotherapist