Spondylolisthesis

What is Spondylolisthesis?

Spondylolisthesis (or anterolisthesis) is the forward displacement of a vertebral body to the vertebrae beneath it. Spondylolisthesis refers to a slippage of a vertebral body relative to an adjacent vertebra. The slippage may occur following structural changes (e.g. fracture or spondylolysis) or degenerative changes in the spine (e.g. spondylosis or degenerative disc disease). Approximately 5% of the population has a spondylolisthesis.

Retrolisthesis is the opposite. The upper vertebral body is displaced backwards relative to the vertebrae below. Laterolisthesis is a sideways shift that is rare. It can occur in advanced degenerative spines or after asymmetrical fractures or severe scoliosis.

Spondyloptosis refers to dislocated vertebrae. In these instances, your spondylolisthesis is so extensive that the upper vertebrae translates entirely forward and off the vertebrae below.  See Grade V below.

What are the Symptoms of Spondylolisthesis?

Spondylolisthesis may not cause any symptoms for years (if ever) after the slippage has occurred. If you do have symptoms, they may include:

• insidious onset low back pain, buttock or leg pain
• pain arching your back
• increased swayback
• tight hamstrings – 80% of cases
• a limp (walking)

What Causes a Spondylolisthesis?

Isthmic vs Degenerative Spondylolisthesis

The two major causes of spondylolisthesis are isthmic spondylolisthesis associated with spondylolysis and degenerative spondylolisthesis associated with degeneration of the posterior facet joints (spondylosis) and/or intervertebral disc (degenerative disc disease).

Degenerative spondylolisthesis occurs mostly (88.5%) at the L4-5 level as opposed to isthmic spondylolisthesis, which occurs most often at the lumbosacral level (L5-S1) (84.6%). Approximately 75% of spondylolisthesis occur at L5 on S1 and 20% at L4 on L5. One study showed that 26% had suffered a fall.

Dysplastic & Other Spondylolisthesis

Dysplastic or congenital spondylolisthesis is caused by poorly formed facet joint structure at birth leading to vertebral slippage.  Other causes related to traumatic or pathological fractures and post-surgical failure are rare.

Spondylolisthesis and Your Age?

Congenital or dysplastic spondylolisthesis has an early childhood onset, as mentioned above.

Isthmic spondylolisthesis is more prevalent in the pre-teen and adolescent years in the athletic youth populations. Sports that involve hyperextension and rotation. e.g. gymnastics, fast bowling (cricket), hurdling, tennis, wrestling and other throwing or overhead racquet sports are higher risks. Spondylolysis (back stress fracture) initially occurs, and about 50% of cases slip to develop into spondylolisthesis.

Most isthmic spondylolisthesis stabilises at skeletal maturity. The fractures themselves may not heal, but it is thought that the muscles controlling the spondylolisthesis provide sufficient functional control to avoid painful symptoms.

Degenerative spondylolisthesis is more common with advancing age.  The vertebrae slip forwards without a fracture present. The slippage is related to chronic spinal segment instability due to co-existing pathologies such as degenerative disc disease or facet joint arthritis (spondylosis). They are also more likely to cause recurrent symptoms.

Due to the vertebrae and arch slipping forward, degenerative spondylolisthesis can cause spinal stenosis and compromise spinal nerve roots. Compromise of the spinal nerve roots may result in a radicular pain syndrome such as sciatica or significant motor power deficits (radiculopathy). In extreme cases, the stenosis and slippage could compromise the cauda equina and develop cauda equina syndrome, a medical emergency and require immediate surgical intervention.

Spondylolisthesis Risk Factors

Known risk factors include:

• Sports involving hyperextension and rotation
• Genetic predisposition. You have a 26% chance that a parent has one.
• Spondylolisthesis: Females 2-3 times
• Spondylolysis (no-slip): Males 2-3 times
• Generalised hypermobility.
• Spina bifida occulta
• Facet joint morphology
• Inuit population
• Degenerative spondylolisthesis is more prevalent in pregnant women and black individuals.

How Is Spondylolisthesis Diagnosed?

Your physiotherapist will begin by taking a history and performing a physical examination. A palpable step or depression may be present to indicate the likelihood of a spondylolisthesis. Your physiotherapist may order X-rays of your back.

A CT scan or MRI scan can show a fracture or pars defect more clearly, plus exclude other potential pathologies such as malignancy, infections or spinal stenosis. They will also show whether any of the nearby facet joints or discs have suffered any degeneration.

If spondylolisthesis is present, it is graded as I (mild), II, III, IV or V based on how far the vertebra has slipped.

Classification by degree of the slippage, as measured as a percentage of the width of the vertebral body:

• Grade I: 0-25%
• Grade II: 25- 50%
• Grade III: 50-75%
• Grade IV: 75-100%
• Grade V: greater than 100% (Spondyloptosis)

Please consult your doctor or physiotherapist for your specific diagnosis, grading and recommended treatment plan.

Spondylolisthesis Treatment

If your physiotherapist or doctor determines that a spondylolisthesis is causing your pain, non-surgical treatment is the primary choice. Treatment will include activity modification plus some specific exercises. Please consult your physiotherapist for a thorough assessment and prescription of the best exercises for your spondylolisthesis. The prognosis is very good for low-grade spondylolisthesis. (Hardwick et al., 2012)

However, the type of exercise that you perform can significantly alter your outcome. One study showed a 73% improvement at 3-months with one exercise group versus only 33% improvement in the alternative exercise group. For advice specific to your spondylolisthesis, please consult with your physiotherapist.

Physiotherapy Treatment

As you begin a physiotherapy treatment regimen, your physiotherapist may prescribe manual therapies or other pain-relieving techniques to reduce your pain and muscle spasms.

Because your muscles are the only effective way of controlling your slipping vertebrae, exercises will be aimed at recruiting your deep spinal stabilising muscles. You may also be prescribed gentle stretches to improve your posture and help to reduce your back pain or leg symptoms.

Flexion-based and localised stabilisation/motor control exercises have been shown to improve pain and disability. (Hardwick et al., 2012, Nava-Bringas et al., 2014)

When you have less pain and improving neurological signs, your exercises will be progressed to improve your flexibility, strength, endurance, and the ability to return to a more normal lifestyle. A comprehensive program may require several weeks or a few months of supervised treatment. For specific advice relative to your spondylolisthesis, please consult your physiotherapist for an individualised assessment.

Spondylolisthesis Prognosis

The presence of spondylolisthesis by itself usually does not represent a dangerous condition in the adult. Outcomes are excellent for low-level spondylolisthesis, with the vast majority of cases having favourable short-term and long-term results.

Most spondylolisthesis Grade I-II patients respond favourably within a few weeks of commencing treatment. A Swedish study showed no significant difference in a long-term randomised study that compared 111 patients who underwent an exercise program versus fusion surgery in adult isthmic spondylolisthesis patients. Patients improved in the short and long term. The follow-up mean was nine years. (Ekman et al., 2005)

Grade III+ patients have less favourable outcomes and may require surgery if they do not respond positively to conservative treatment.

Secondary Spondylolisthesis Treatment Options

Pulsed Radio Frequency (PRF) is a pain management technique that can be administered to your facet joint nerves in recalcitrant cases. Researchers have found it is more effective than epidural steroid injections, which is another short-term pain-relieving option. (Hashemi et al., 2014)

Spondylolisthesis Surgery?

Surgery is occasionally warranted if you have failed your exercise-based conservative treatment. 10-15% of patients with degenerative spondylolisthesis have surgery. If there is a failure to improve radiculopathy, e.g. muscle weakness, poor function or another neurological deficit such as loss of bowel or bladder function, surgery is considered. Persistent severe pain is also a consideration for surgery.

Surgery for isthmic spondylolisthesis is considered for athletes with Grade III+ slips if they have failed 6-months of conservative exercise rehabilitation. (Radcliff et al., 2009)

Your surgery options are best discussed with your Spinal Surgeon, but they would typically involve a spinal decompression +/- spinal fusion.

Fortunately, conservative exercise options are successful in the vast majority of Grade I-II cases. Please consult with your physiotherapist for their professional assessment and specific treatment guidance for your spondylolisthesis.