The risks of hip arthroscopy, honestly explained

Complications can occur during or after any operation: unintended events that may be harmful, without anything having been done wrong. Complications are among the accepted risks of a procedure — we do everything we can to keep the chance of them as small as possible.

After surgery, clots can form in the veins of your legs (venous thrombosis); occasionally such a clot travels to the lungs (pulmonary embolism). Your risk is higher if thrombosis runs in your family, if you have had it yourself before, if you use the contraceptive pill, or if you have a clotting disorder. After surgery, watch for pain, swelling or redness of the calf, or shortness of breath. To reduce the risk, you receive a blood-thinning injection for two weeks. Moving early and sufficiently after surgery also reduces the chance of thrombosis.

Very occasionally, bacteria enter the surgical area or the joint through the small surgical wounds. Symptoms include pain, redness, fluid or pus from the wounds, fever, or generally feeling unwell — contact the clinic if this happens. Infection after a hip arthroscopy is extremely rare, partly thanks to antibiotics given before surgery, sterile technique, and continuous irrigation of the joint during the procedure.

Before surgery, a few small 'tunnels' are made through skin, tissue and capsule; a small blood vessel can be nicked in the process. Symptoms include swelling, pain and blue or purple discolouration around the wounds. Post-operative bleeding almost always stops by itself and needs no further treatment. Note: the surgical wounds may leak a little from time to time in the first hours after surgery; this is usually the irrigation fluid used during surgery with a small amount of blood mixed in — this is not post-operative bleeding.

Nerves run around the hip that can be affected during surgery. This is usually a limited, temporary injury to the nerve that supplies sensation to the skin at the front and side of your thigh (lateral femoral cutaneous nerve): this causes a numb or tingling feeling, without loss of strength, and is usually temporary but can sometimes be permanent. In addition, traction on your leg during surgery can temporarily 'bruise' other nerves, causing short-term loss of sensation or strength in the leg, or — in men — temporary impotence; this risk is smaller (approximately 1 in 100) and always resolves on its own.

Blood vessels supplying the femoral head run along its back surface, particularly relevant when treating a cam deformity. If these are damaged, impaired blood supply to the femoral head can develop (osteonecrosis): a rare but troublesome complication that sometimes requires an additional procedure, and in the most severe case a hip replacement.

Sometimes new bone forms around the joint after surgery (periarticular ossification). This is a rare complication, with an estimated risk of around 1 in 500. Taking an anti-inflammatory pain reliever (meloxicam) for the first two weeks after surgery helps reduce this risk.

To create enough space between the femoral head and the socket, the hip is placed under traction during surgery. If the hip is tight, inserting the camera and fine instruments can cause a small, unintended injury to cartilage or the labrum. This is usually very limited and generally has no effect on your recovery or on the risk of osteoarthritis; sometimes such incidental damage is treated at the same time. If the hip is so stiff that little space can be created, the chance of such damage is somewhat higher. In a rare case, no space forms between the head and socket at all; the hip can then not be fully visualised, and the full treatment cannot be carried out.

A hip arthroscopy is performed under general anaesthesia or with a spinal anaesthetic (spinal anaesthesia). These forms of anaesthesia also carry risks and side effects — for example, temporary nausea, a sore throat from the breathing tube under general anaesthetic, or a headache after spinal anaesthesia. Your anaesthetist discusses this with you in detail, specific to your situation, before the operation.

Aside from complications, there is also a chance that the operation does not have the desired effect, or that symptoms return over time. In a small proportion of cases, a further procedure is then needed at a later stage. Also read the page on results.

Always contact the clinic if the wound starts leaking, becomes more swollen or more painful, if the wound area feels red and warm, if you develop a fever, or if you notice a tight, swollen and warm feeling in your lower leg or calf — the latter can indicate thrombosis.