I don't know about crystals but would certainly recommend some Arnica - either a homoeopathic tablet (dissolved under the tongue) taken about four times a day or else a cream or oil massaged in. It will reduce any remaining bruising or swelling and should make the knee much more comfortable as a result. Homoeopathic Staphysagria is also good for resolving the after effects of an operation. Take either remedy in a 6 potency which should be available from a good health store, or you can order from an online homoeopathic pharmacy. (Spelled homeopathic in the US.).
