The arthroscope is a fibre-optic telescope that can be inserted into a joint (commonly the hip, shoulder, knee and ankle) to evaluate and treat a number of conditions. A camera is attached to the arthroscope and the picture is displayed on a TV monitor.
The arthroscope is an excellent means of examining the whole of the hip and many conditions can be treated at the same time. Hip arthroscopy is a developing technique and is only practised by highly specialised orthopaedic surgeons.
There are several indications for undertaking arthroscopy of the hip:
- General diagnostic purposes; for example in early osteoarthritis
- Torn acetabular labrum: the labrum is trimmed to a stable rim or occasionally repaired
- Damaged articular (surface) cartilage; the damaged area is trimmed so that it has a stable margin. Deep defects may need microfracture where a small, sharp pick is used to perforate the underlying bone and encourage healing
- Removal of loose bodies (cartilage or bone that has broken off)
- Resection of inflamed lining tissue (synovectomy)
- Treatment of hip impingement. Resculpting of the femoral neck can be performed arthroscopically. This can be combined with labral repair
Most arthroscopic hip surgery is undertaken as an inpatient procedure and is performed under general anaesthesia. Patients are admitted on the day of surgery and need to remain fasted for 6 hours prior to the procedure. The hip undergoing the procedure will be identified and marked prior to the anaesthetic.
Traction is applied to the leg to allow access to the hip joint and x-ray is used throughout the procedure. The arthroscope is introduced through a small (approximately 0.5-1.0cm) incision on the outer side of the hip. A second incision on the front of the hip is made to introduce the instruments that allow examination of the joint and treatment of the problem. Usually a third incision over the outer part of the hip is also required, particularly if resculpting for impingement is planned.
Local anaesthetic is administered into the hip by the surgeon at the end of the procedure. This usually provides 8-12 hours of pain relief. A dressing pad is applied to the operated hip.
- Once the patient has recovered their intravenous drip is removed and they are shown a number of exercises to complete
- The surgeon sees the patient and explains the findings of the operation and what was undertaken during surgery
- Pain medication will be provided and should be taken as directed
- The pad can be removed after 24 hours and waterproof dressings applied over the wounds
- The patient will be mobilised with the help of the physiotherapists. Crutches are usually necessary
Following surgery patients are given an instruction sheet showing exercises that are helpful in speeding up recovery.
Strengthening the buttock (glutei) and thigh muscles (quadriceps and hamstrings) is very important; cycling (stationary or road) and swimming are excellent ways to build these muscles up and improve movement. Core stability is also an important issue to address.
Return to driving and work is variable and usually at the patient’s discretion.
General Anaesthetic risks are extremely rare. Occasionally patients have some discomfort in the throat as a result of the tube that supplies oxygen and other gases.
The risk of complication from arthroscopic hip surgery is also rare and is generally related to the use of traction or the creation of skin portals for access. Occasionally stiffness of the hip will prevent arthroscopy from being possible; sometimes symptoms may be made worse by arthroscopy (<5%).
- Temporary nerve paralysis causing numbness over the side of the leg or in the groin
- Pressure areas in the groin from the traction post
- Damage to the cartilage or labrum within the hip joint
- Postoperative bleeding
- Deep Vein Thrombosis
- Injury to vessels, nerves or a chronic pain syndrome
- Progression of the disease process
The early results of arthroscopic resculpting to treat femoroacetabular impingement are very encouraging. Eighty five percent of patients report marked improvement in symptoms at 1 year. The long term results are not yet known, however, occasionally there is more damage in the hip than was initially thought; this can affect the recovery time.
If the cartilage in the hip is significantly worn out then arthroscopic surgery has only about a 75% chance of improving symptoms in the short to medium term: more definitive surgery (e.g. hip replacement) may be required in the future.
In general arthroscopic surgery does not improve hips that have well established osteoarthritis but may give symptom relief for a period of time. This is useful in young patients who are not keen on joint replacement.