Patella or Knee cap dislocation happens when the patella slips out of its socket and sits on the outer [lateral] aspect of the thigh bone [Femur]. People prone to such events include females, people with mal-alignment of the knee [excessive valgus knee], hyper lax individuals etc. However it also happens in many otherwise normal people. The best treatment in a dislocated patella is to reduce it immediately under anaesthesia.
When the patella or knee cap dislocates repeatedly it is called recurrent patella dislocation. This is a serious issue and if not dealt with appropriately it shall result in premature wear and tear[osteoarthritis] of the knee cap cartilage.
Non Operative treatment
With single or sometimes two episodes of dislocation the non operative measures shall suffice. These include strengthening your inner thigh[medial] muscles including the Vastus Medialis, use of braces etc.
The appropriate operation to be performed is determined by your orthopaedic specialist based on your bony anatomy, clinical examination findings. The patient may be asked to undergo an MRI scan and a CT scan to determine what are the structures at fault and what operative procedure needs to be done. Medial Patellofemoral ligament [MPFL] reconstruction is the most commonly performed surgery for recurrent dislocation patella. This can be performed with arthroscopic assistance or open. Other surgical options like osteotomies are reserved for special cases with specific indications.