The Janu means Knee joint and Basti – means to hold (compartment which holds). Thus Janu Vasti means a treatment in which medicated oils are poured and pooled for a fixed duration of time in a compartment or a cabin constructed around the knee joint / joints using wet flour of black gram.
In simple words, Janu Basti is pain relieving oil-pooling treatment conducted for knee pain caused due to many causes.
Vasti or Basti is a term used to describe the urinary bladder in Ayurveda. Urinary bladder is a bag which holds urine for a certain amount of period till it is voided. Janu basti is one of the upakarma (sub-type) of Panchakarma. The word janu refers to knees and Basti stands for container or retaining something inside mainly the medicated oil. This procedure is done in order to strengthen the knee architecture i.e muscles, joints and improvise the functions of knee joint thereby preventing it from further degenerative changes.
Similarly in Janu Vasti a compartment (cabin or compound like structure) is constructed around the knee joint (front or back, depending on where the site of degeneration or inflammation or injury is present) by using flour of black gram and the pain relieving medicated (herbal) oils are pooled and left in place (retained) in this compartment for a fixed duration of time. Therefore the procedure is called Janu Vasti.