What is Pseudoarthrosis?
Pseudoarthrosis is also known as bone nonunion. It occurs when the bones do not fuse as they normally should after an injury or surgical procedure.
For example, sometimes surgeons do spinal fusion surgery for problems of bones, spine, and vertebrae. It involves the fusion of the vertebrae into one solid bone to help increase stability. It is used to repair fractures or improve scoliosis.
It was observed in a study that 50 % of spinal fusion surgery failed and the surgeons had to perform more operations.(1)
Pseudoarthrosis can be a serious condition depending on what bones are affected by it. If a person’s neck bone is affected, there can be difficulty in moving the neck.
Pseudoarthrosis can be the main reason for pain after surgery. However, it is observed that there may be no symptoms in about 30% of people.(1)
Causes and Risk Factors of Pseudoarthrosis
There are several factors that cause pseudoarthrosis:
- Moving After Surgery: If a person starts moving too soon post-surgery before the bones have started the fusion process, pseudoarthrosis can occur.
- Medical Condition: There are certain medical conditions such as ankylosing spondylitis that can increase the risk of pseudoarthrosis.
- Congenital Conditions: Pseudoarthrosis can be a congenital condition in very rare cases.(2)
- Surgical Techniques: It was concluded in a study that pseudoarthrosis can also occur due to the risk of certain surgical approaches.(3) Amongst the various surgical approaches, techniques involving long fusion, osteotomies, and pelvic fixations may increase the risk of pseudoarthrosis. Additional surgical factors that may increase the risk of suffering from pseudoarthrosis include the number of levels fused, type of fusion, placement of the graft, condition and preparation of graft, choice of graft, and whether it is a revision of graft.
Risk Factors Of Pseudoarthrosis Include:
- Metabolic conditions
- Vitamin D deficiency
- Long-term steroid use
A study reviewed data from people who developed an infection of the spine at the surgical site. It was observed that the spine level undergoing fusion was the main predictor of a person developing pseudoarthrosis.(4)
Symptoms of Pseudoarthrosis
Pseudoarthrosis may lead to the following symptoms in people:
- Reduced mobility
- Persistent pain
- Clicking of the joints
Diagnosis of Pseudoarthrosis
Sometimes diagnosing pseudoarthrosis may be difficult. One of the reasons is that a person may not notice symptoms. Sometimes the symptoms may be noticeable after a few months and even years after surgery.
Pseudoarthrosis can be diagnosed with the help of an x-ray or CT scan. These tests can be helpful in giving a detailed picture of the skeleton.
Treatment of Pseudoarthrosis
Treatment for pseudoarthrosis may start with conservative treatments including medications, physical therapy, or pain management. These treatments are adopted especially in cases, where ruling out other sources of back pain or neck pain is important.
The treatment for pseudoarthrosis is surgery. If the bone fusion is previously failed, surgery focuses on repairing it the second time.
The spine affected by pseudoarthrosis can be treated by:
- Replacing loose implants
- Using stronger tissue replacements
- Interbody fusion, involving removing the spongy disc between the vertebrae
Surgery is also recommended for the treatment of congenital pseudoarthrosis. It involves resecting the clavicle using a bone graft from the iliac crest into the pelvis.(5)
Treatment of congenital pseudoarthrosis of the tibia can be challenging. But it was observed that only 50% of the surgical procedures resulted in healing without refracturing.(6)
Another possible treatment is electrical stimulation therapy. A study found it to significantly increase the fusion rate in people undergoing spinal fusion.(7)
Pseudoarthrosis is a condition in which two bones do not fuse successfully post-surgery or fracture treatment. It is a common complication after spine fusion procedures. Some people with pseudoarthrosis have no symptoms while a few may show loss of mobility, pain, and clicking sounds. Additional surgical procedures may be needed to treat it.