Loose bodies are fragments made up of cartilage, bone or a mixture of both which get detached and usually move within the joint. They are usually a result of an injury or even a joint disorder; termed as Osteochondritis Dissecans or OCD (OCD is a condition when a small segment of bone begins to separate from its surrounding region due to a lack of blood supply.). The size of the fragment can vary from very small to large ones. The larger fragments are generally the ones which cause symptoms such as locking or catching of the joint when they get wedged between the joint surfaces. This can also lead to considerable pain and can cause the joint to fill up with fluids and swell.
- Fragments containing bone can be diagnosed on a simple x-ray
- Damage to cartilage are better visualised on an MRI scan
Treatment depends on several factors and is usually by arthroscopy (key-hole procedure). Smaller fragments are excised. Larger fragments can also be excised unless they arise from important weight bearing areas of the joint surface. Surgeons may decide to try and reposition the fragment back to its origin and secure it using pins or screws which may be metallic or bio absorbable depending on the surgeons' choice.
If the fragment has been excised, then post operation, weight bearing as normal is allowed. However, if the fragment is repaired, then patients will be provided with crutches to take the pressure off the affected knee. Knee movement is gradually commenced up to a certain limit to prevent pressure on the repaired cartilage. This will be determined by the surgeon based on the location of the repaired cartilage.
Results from this procedure are satisfactory, however, failures are known to occur and the fragment may require excision if it fails to heal and detaches again.