All operations have risks and dangers, and these these to be weighed carefully against the potential benefits of the operation being performed. There are of course specific risks related to particular operations, but there are general risks in common with all orthopaedic operations.
Most orthopaedic surgery operations require the patient to be under a general anaesthetic. Some operations can be done with regional "half body" anaesthetics, and small operations can be done with just local anaesthesia injections. Most knee, shoulder, hip and ankle surgeries including arthroscopy, need to be performed under either general or regional (not local) anaesthesia. Anaesthesia can cause serious problems to any of the major organs of the body including the heart, lungs, brain, kidneys and liver. Thankfully, the risks of a serious major anaesthetic complication in generally healthy patients is estimated to occur only 1 time in every 100,000 operations.
Wound infections, wound bleeding or wound healing problems may occur. Minor problems of this nature can occur with all orthopaedic operations about 1-2% of the time. Most of these problems can be treated with simple measures such as extra antibiotics, extra wound dressings, or minor operations to drain the retained blood. These problems rarely affect the eventual good result of surgery.
Injury to nearby bones, ligaments, muscles, nerves, cartilage and other tissues can occur with all operations. Generally the risk of major permanent damage to nearby structures or organs is extremely small.
Severe deep infection is a very serious complication that is estimated to occur between 0.1-1.5% of the time depending on the type of operation that is being performed. In most healthy patients undergoing planned orthopaedic operations, the risk is about 0.2%, or 1 in 500 patients. It is often impossible to determine where the germ came from, because this complication still occurs despite all the best precautions (antibiotics, quick efficient surgery with a good surgeon, clean high standard hospital). Often the germ is a normal bacteria that lives on the patient's skin. Unfortunately if this complication does occur, this might need to be treated with one or more operations to wash the infected area, and 1-2 months of antibiotics to kill the remaining germs. In addition, the infection may damage the original operation, and cause the original operation to fail. Thankfully this devastating complication only occurs about 0.2% of the time.