Does my low back pain mean I'm really missing a lumbar vertebra?

Bertolotti syndrome is not actually a missing vertebra. Instead, the transverse process of the fifth lumbar vertebra forms an abnormal fusion with the sacrum or ilium, creating a lumbosacral transitional vertebra (LSTV). This congenital structure places greater mechanical stress on the area, which can lead to low back pain.

Does this condition always require surgery?

In most cases, no. The article notes that conservative treatment is the main approach, including anti-inflammatory pain relief, manual therapy, exercise training, and local injections, and most patients improve. Surgery is only considered when conservative treatment is ineffective and symptoms continue to affect quality of life. Research suggests surgical outcomes are only slightly better than conservative treatment, so the decision needs careful evaluation.

Why did my low back pain start when I was young?

Because Bertolotti syndrome is congenital, the structural abnormality may already be present at birth, but symptoms usually begin to appear in adolescence or early adulthood, around the ages of twenty to thirty. There is no clear difference in occurrence between men and women.

What makes my symptoms worse?

Pain usually worsens after prolonged standing, walking, or physical activity, and is sometimes accompanied by hip or buttock pain. People with a related family history, a past history of spinal or sacroiliac trauma, or repeated overuse of the lower back are more likely to develop or worsen symptoms.

Does exercise training help with this condition?

Exercise training is an important idea for reducing recurrent pain over the long term. The focus is on strengthening and improving the flexibility of the lower back, pelvis, and hip muscles — for example, core stability training and posture correction — which may help reduce the load on the spine. The program still needs to be adjusted to each individual's situation.

Is Your Low Back Pain Because You're Missing a Lumbar Vertebra? A Look at Bertolotti Syndrome

Bertolotti syndrome is a low back pain syndrome caused by a congenital malformation of the lumbosacral region. Its most common feature is abnormal fusion between the transverse process of the fifth lumbar vertebra (L5) and the sacrum or ilium, producing an atypical bony structure that increases mechanical stress and the risk of pain in that area. This malformation is known as a lumbosacral transitional vertebra (LSTV), and it can lead to low back pain and limit daily activities.

Epidemiology

The prevalence of Bertolotti syndrome is estimated at about 4% to 8% of the general population.
Because it is congenital, the condition may be present at birth, but symptoms usually begin to appear between the ages of 20 and 30.
There is no clear difference in incidence between men and women.
It is defined according to the Castellvi system from 1984. The four types of LSTV are:
Type I — a dysplastic transverse process at least 19 mm wide: the most common at 42%.
Type II — transverse process growth producing incomplete sacralization or lumbarization: 38%.
Type III — complete sacralization/lumbarization of the transverse process: 8%.
Type IV — a mix of complete sacralization on one side and incomplete sacralization on the other: 5%.

Pathophysiology

The main cause is a transitional structural abnormality between the fifth lumbar vertebra and the sacrum or ilium. This may be a partial or complete fusion, producing structural and biomechanical changes in the area.
Some research suggests the cause may originate from an abnormal iliolumbar ligament. Studies have found that in these patients, the iliolumbar ligament on the side of the abnormal joint is far less developed than the ligament on the opposite side.
These structural abnormalities alter the mechanical load on the spine, causing the surrounding soft tissues and joints to bear abnormal stress, which in turn triggers chronic low back pain.
The intervertebral disc just above the transitional segment, most often L5-S1, typically degenerates far faster than other discs. The underlying mechanism may involve sacroiliac joint inflammation, disc herniation, or nerve compression, all of which can worsen low back pain symptoms.

Risk factors

Family history: because Bertolotti syndrome is congenital, a family history of this type of bony malformation may increase the risk.
History of spinal injury: trauma to the spine or the sacroiliac region may trigger or aggravate symptoms.
Overuse: repeated lumbar movements during physical labor or sport may make symptoms more likely to appear.

Clinical history

Patients with Bertolotti syndrome typically complain of low back pain, especially persistent chronic pain, which may begin in adolescence or early adulthood.
Pain usually worsens after prolonged standing, walking, or physical activity, and may be accompanied by hip pain or buttock pain.
The history may include past lumbar trauma or a history of persistent overuse from exercise, both of which can contribute to worsening symptoms.

Physical examination

The examination focuses on the range of motion of the spine, particularly the lumbar and sacroiliac joint regions. Pain usually worsens with lumbar movements such as forward bending or side bending.
Palpation of the hip and sacroiliac joint may provoke pain, indicating that these areas may have abnormal stress or inflammation.
Strength and sensation in the lower-limb muscles are usually normal, but in some severe cases there may be signs of nerve compression, such as sciatica or lower-limb numbness.

Differential diagnosis

Disc herniation: may produce similar low back pain and sciatica symptoms.
Degenerative lumbar disease: an age-related spinal condition that also causes chronic low back pain.
Sacroiliac joint dysfunction: this condition typically affects the sacroiliac joint and causes low back and buttock pain.
Hip pathology: conditions such as hip impingement syndrome may produce similar hip pain.

Diagnostic tools

X-ray: clearly shows the bony fusion between the fifth lumbar vertebra and the sacrum or ilium, which is the key diagnostic basis for Bertolotti syndrome. In addition, a lateral X-ray shows the typical appearance of an LSTV, with a squared-off transitional vertebral body and reduced transitional disc height.
CT scan or MRI: these imaging tools can further examine the spinal soft tissue and nerve compression, and rule out other possible causes such as disc herniation or nerve compression.
Sacroiliac joint injection test: if sacroiliitis is suspected, a local anesthetic injection can be used to determine whether that joint is the source of pain.

Initial treatment

Conservative treatment is the main approach for Bertolotti syndrome, usually including pain relief medication and injection therapy.
- Anti-inflammatory drugs (NSAIDs): commonly used to reduce pain and inflammation.
- Manual therapy: some patients may benefit from spinal manipulation or joint mobilization.
- Exercise training: focuses on strengthening the lower back muscles, stabilizing the spine, and improving posture and movement patterns.
- Local injection: when there is pain, local corticosteroid injection, anesthetic medication, or prolotherapy injection may help reduce inflammation and pain.
In some difficult-to-control cases, a physician may suggest short-term use of a back brace or bed rest to ease symptoms.
The main treatment pathway can be used as a reference.

Additional treatment

Exercise training: an important idea for reducing recurrent Bertolotti syndrome pain over the long term. The focus is on improving the strength and flexibility of the lower back, pelvis, and hip muscles to reduce the load on the spine. Common approaches include:
- Core stability training: strengthening the abdominal and back muscles to support the spine.
- Traction therapy: in some patients, traction may help reduce spinal load and ease pain.
- Posture correction training: reducing the mechanical stress on the transitional vertebra by improving the patient’s standing and walking posture.
Radiofrequency ablation.

Surgery

When conservative treatment is ineffective and symptoms continue to affect quality of life, surgical intervention may be considered. Common surgical options include:
- Lumbar transverse process resection: removing the transverse process that has abnormally fused with the sacrum or ilium to reduce local abnormal stress and thereby relieve pain.
- Spinal fusion: for patients with severe instability or accompanying disc degeneration, lumbar or sacroiliac joint fusion may be effective, but this surgery is more complex and carries higher risk.
The decision to operate depends on the severity of the condition, the response to conservative treatment, and the patient’s quality of life, and should be discussed in detail with a specialist spine surgeon. Research suggests that surgical outcomes are only slightly better than conservative treatment, so surgery is advised only for selected patients, who should have their disc pathology carefully examined.

Follow-up

Patients with Bertolotti syndrome need regular follow-up to monitor pain control and treatment response, and the use of physical therapy and medication should be adjusted according to changes in symptoms.
Watch for any new neurological symptoms or worsening pain, which may indicate a need for further imaging or a change in the treatment plan.
If the patient undergoes surgery, the postoperative rehabilitation plan will include further manual therapy, exercise training therapy, and lifestyle management to help prevent recurrence.

Prognosis

Most patients with Bertolotti syndrome can obtain meaningful relief of symptoms and return to normal activity through conservative treatment such as exercise training, medication, and injection therapy.
For patients who need surgery, the outlook after surgery is generally good, but the recovery period may be long, and ongoing core training may be needed to maintain the result.
Early diagnosis and intervention may reduce the frequency and severity of pain episodes and help patients maintain a good quality of life.

References

Int J Spine Surg. 2015 Jul 29:9:42.
https://en.wikipedia.org/wiki/Bertolotti’s_syndrome
Orthop Rev (Pavia). 2021; 13(2): 24980.
Spine. 1984;9(5):493-495.