Introduction
Cause
Symptoms
Diagnosis
Non-surgical treatment
Surgical treatment
Osteophytes, commonly known as bone spurs, is the medical term for overgrowth of bone tissue (or bony projections) at the periphery of joints, producing lips of bone. This type of osteophytes is called marginal osteophytes. The growth of osteophytes is a reaction of the body tissue to wear and tear, degeneration of the joint. Most of the bone spurs themselves should not be painful.
Bone spurs are common and can develop on different joints within your body. More important ones are from joints lined with synovial tissue and stabilized with a fibrous joint capsule. Under this condition, bone spurs typically develop as a reparative response form from the tissue that lines the periphery of a degenerating joint (Marginal osteophytes). Commonly talked about are those from the knees. These bone spurs typically appear as small round lumps of bony projections at the periphery of joints on X ray. They are not necessarily sharp as suggested by its Chinese name.
People with degenerative knee joints (osteoarthritis) are typical examples. Osteoarthritis is a disease of the whole joint, with thinning or loss of articular cartilage, wear and tear of the subchondral bone and a incompetent joint capule, not just formation of bone spurs at the margin of joint surfaces. Other pathological process involved may include cartilage erosion, synovial inflammation and hypertrophy, accumulation of joint effusion, narrowing of the joint space and formation of intra-articular osseous loose bodies etc. In severe cases, there are other changes including bone loss, laxity of supporting ligaments, resulting in joint deformity and mal-alignment. It is the degenerated joint that is producing the osteoarthritic symptoms and not the osteophytes. The osteophyte is innocent. In fact, it helps to control arthritic symptoms by limiting the joint movement.
Occasionally, osteophyte can be the cause of symptoms:
1. Localized pain on prominent projections if it is very superficial.
2. Pressure or tightening effect on joint capsules or ligaments, limiting joint motion and occasionally responsible for joint malalignment.
3. Pressure on adjacent vital structures such as nerve roots, peripheral nerves or blood vessels:
More often occurs in the cervical spine , osteophyte from the synovial joints on the periphery of the intevertebral disc or the segmental facet joint may irritate or impinge on the nerve roots exiting in the intervertebral foramina, causing paraesthesia, root pain or weakness of the the upper limbs. Rarely, osteophytes from the intervertebral disc may encroach on the vertebral arteries, affecting the cerebral circulations.
4. Breakage from the joint surface, producing localized pain or becoming a loose body in joint.
Bone spurs can also be found where ligaments and tendons are attached to bones. Example includes heel spur where the plantar fascia connects to the heel bone (calcaneus), the clinical condition is called plantar fasciitis in medical term. The spur results from chronic irritation or inflammation of the connective tissue, but the spur itself doesn't cause the pain associated with plantar fasciitis.
Bone spurs can also form on the bones (vertebra) of a degenerating spine, known as spondylosis in medical term.
Most bone spurs cause no sign or symptom. Quite often, most of the people do not even realize the presence of bone spurs not until an X-ray was taken for another condition which incidentally reveals the bony protrusions. Usually, the medical conditions resulting in formation of bone spurs that cause signs and symptoms; not the bone spur themselves.
In a degenerating synovial joint, for example knee joint, typical symptoms may include joint pain with activity, joint swelling, joint crepitus with motion, loss of motion and deformity. The main functional problems are disturbing pain with activity and decreased joint mobility.
Encroachment of spinal neural tissues (nerve roots or spinal cord) can result in pain, numbness and weakness. Neurological symptoms can be caused by protruded intervertebral disc from the front, and hypertrophied ligamentum flavum and degenerated facet joints from behind. Detail imaging will be able to differentiate and localize the exact pathology.
In certain areas, osteophytes can be diagnosed by clinical examination. Examples include prominence (Heberden’s nodes) at the DIPJ (distal interphalangeal joint) of hands; because these joints are superficial. More commonly, osteophytes are diagnosed by plain radiographs (X-rays).
Plain radiographs taken on ordinary people over 50 years of age would probably show some osteophytes around the knee joints or in the spine. Yet, most of these people with osteophytes are relatively asymptomatic.
There is no specific treatment for bone spurs. Usually, one does not need any treatment for asymptomatic bony spurs. Symptoms and signs, if present, are typically related to the underlying pathologies. Therefore, treatment is logically directed towards the underlying problem instead of the bony spurs alone. The main goals of management are:
To educate patient about their diseases and the principles of management
To control pain
To improve functional status
Non-surgical treatment:
There are effective non-surgical treatment available for the management of degenerative synovial joints. Non-pharmacological treatments include “rest”, cryotherapy, physiotherapy, and use of walking aids; these treatments should be tried first. Modifications of activities of daily livings can help control of symptoms in the long run. Medications can help control of pain.
Surgical treatment should be considered when conservative treatment failed. Your orthopaedic surgeon can decide for you which surgical option is appropriate, usually depending on your particular underlying orthopaedic conditions. For example, total knee replacement may be an appropriate surgical option for elderly patients with symptomatic severe degenerative knee joints not responding to conservative treatments. High tibial osteotomy or unicompartmental arthroplasty may be an appropriate surgical option for “younger” patients with symptomatic unicompartmental degeneration of knee joints not responsive to conservative treatments. Bone spurs are often removed as part of the chosen surgical procedure.
Surgical intervention aiming at “removing” bone spurs alone is seldom indicated.
Dr. YU, Kong-san