Loose bodies are pieces of cartilage or bone that are loose within the hip joint and are able to ‘float’ around inside the joint.
These loose bodies can cause damage and get locked or jammed inside the hip joint, leading to pain.
Loose bodies can come from injuries leading to fragments of bone or cartilage, the breakage of bone spurs (called osteophytes) or from a condition called Synovial chondromatosis. Synovial chondromatosis is a condition where the lining of the joint develops multiple loose bodies.
Loose bodies can be removed through hip arthroscopy.
Symptoms
Loose bodies cause a number of symptoms:
- Pain: the loose body can irritate the joint surfaces and also the fibrous coating of the joint known as the capsule. This can lead to inflammation of the joint resulting in pain.
- Clicking: clicking can occur if the loose body gets trapped between the two joint surfaces of the hip and then dislodges as the hip moves
- Locking: if a loose body gets wedged between the two joint surfaces and remains stuck, the hip may get stuck and not be able to move further in one direction
Causes
- Osteoarthritis: Wear and tear of the hip joint can lead to bone spurs and roughening of the cartilage that forms the joint surfaces. This can lead to a bone spur or a piece of cartilage breaking off and floating around within the joint.
- Synovial chondromatosis: is a disease affecting the synovium, a thin flexible membrane that lines the joint and keeps the joint well lubricated. In this disease, the thin flexible membrane of the synovium gradually forms blisters which harden and enlarge. These nodules eventually break free and float around in the joint
- Trauma: A car accident or other high force injury, especially if there is dislocation of the hip, can cause a piece of bone or cartilage to be broken off within the joint creating a loose body
Risk Factors
The following conditions are risk factors for developing loose bodies:
- Osteoarthritis: The presence of bone spurs and roughened cartilage make the formation of loose bodies more likely
- Synovial chondromatosis: The presence of this condition is a significant risk factor for the formation of loose bodies. Most people with this condition will go on to develop a loose body at some stage.
- Legg-Calvé-Perthes disease: fragments may occur as a result of osteochondritis dissecans (cartilage breakage)
Investigations
The presence of loose bodies can often be diagnosed by taking a thorough history and performing a clinical examination of the hip.
The clinical diagnosis can be confirmed using imaging such as X-ray or MRI imaging. An X-ray will usually be performed first but may not always show up the loose body. An MRI scan may be ordered which gives a more accurate diagnosis of the size and location of the loose body.
Complications
If a loose body is left within a joint, it can cause damage to the cartilage that lines the joint surfaces. This can lead to early wearing out of the joint surfaces and the onset of osteoarthritis.
For this reason it is important that the hip is assessed by a doctor or orthopaedic surgeon and appropriate treatment is carried out before permanent damage occurs.
Treatment
Loose bodies are treated with arthroscopic surgery. This involves making small incisions (1- 2cm) in usually three places around the hip and then inserting small instruments and a small camera into the hip joint.
The loose body will be removed and any other damage assessed. If there is a tear to the labrum or ligamentum teres then this can be repaired at the same time.
Seeking Advice
Your Family Doctor (GP)
Your Family Doctor will be able to diagnose and help treat your problem. He or she will be able to:
- tell you about your problem
- advise you of the best treatment methods
- prescribe you medications
- and if necessary, refer you to an Orthopaedic Surgeon for further treatment
Sports Physician
Is a doctor who specialises in sports injuries. A Sports physician is well trained to diagnose the presence of loose bodies and help you though your treatment before and after your surgery.
Orthopaedic Surgeon
An orthopaedic surgeon trained in hip arthroscopy will be able to treat loose bodies. As hip arthroscopy is a specialised technique, your orthopaedic surgeon may need to refer you to a surgeon who has been trained in the technique.
Prevention
Unfortunately loose bodies due to osteoarthritis and trauma are hard to prevent. If you have been diagnosed with the condition of synovial chondromatosis then you will need to follow the advice of the treating physician but anti-inflammatory therapy may help in reducing the formation of loose bodies.