The Importance of Spinal Stability

In everyday situations, good control of both flexion (leaning forward) and extension (leaning backward) of the spine is important. Flexion is particularly important in many activities of daily life, such as work, exercise, and even passive leisure activities such as reading.1–4

The Importance of Spinal Stability

In some cases of degenerative spinal disease, surgery becomes necessary. Surgical decompression of the lumbar spine involves the careful removal of soft tissue and bone that are compressing nerves and causing pain. Usually, surgical decompression improves symptoms in the short term. However, the removal of soft tissue and bone sometimes increases spinal instability, particularly when the spine is in flexion. Such instability can lead to symptoms returning and even getting worse.

What is Lumbar Spinal Stenosis?

Spinal stenosis is a common disease of the aging lumbar spine. It involves a narrowing of the space around the spinal cord and the nerve roots in the lower back. The narrowing can be a result of bone-overgrowth around the facet joints and enlarged ligaments, which put pressure on nerves and cause pain, numbness, and weakness in the legs and hips with an impaired ability to walk and, in some cases, back pain.

What is Degenerative Spondylolisthesis?

Some patients who have lumbar spinal stenosis also have degenerative spondylolisthesis, where one vertebra slips forward relative to another. The slip causes compression of the spinal canal and associated symptoms. In addition, patients with degenerative spondylolisthesis often have excessive movement, or instability of that part of the spine, when they bend forward and flex their lumbar spine.

Normal (Mechanism_01)


Degenerative Spondylolisthesis

Degenerative Spondylolisthesis

Treatment Options

The symptoms of patients with lumbar spinal stenosis with or without degenerative spondylolisthesis can sometimes be successfully addressed with non-operative treatments such as physical therapy and medications. When non-operative treatments fail, surgeons often elect to perform surgical decompression. After such surgical removal of bone and soft tissue that are pushing on the nerves, symptoms usually improve in the short term. However, the removal may increase spinal instability. This can lead to symptoms returning and even getting worse.

In some cases, it is necessary to stabilize the treated spinal segment after surgical decompression using a spinal implant. Rigid fixation and fusion is accepted as the gold standard for stabilization of patients with segmental instability.

Mechanism Rigid fixation

Rigid fixation with pedicle screws and rods with the goal to fuse the hypermobile segment

The LimiFlex™ Paraspinous Tension Band

The LimiFlex™ Paraspinous Tension Band is a new potential alternative to spinal fusion for patients receiving surgical decompression for grade 1 lumbar degenerative spondylolisthesis with spinal stenosis.

LimiFlex™ is made of two spring-like titanium rods attached to each other by strong textile straps. LimiFlex™ forms a loop around two spinous processes (fin-like projections at the back of each vertebra), to stabilize the spine when bending forward.

LimiFlex™ may allow surgeons to stabilize the spine without the need for more invasive spinal fusion.

LimiFlex™ allows surgeons to stabilize a spinal segment without the need for spinal fusion.

Lumbar spine in flexion

Lumbar spine in flexion

HP13 Flexion with LimiFlex

Lumbar spine in flexion with LimiFlex™



1. White AA, Panjabi MM. Clinical Biomechanics of the Spine, Second Edition. Lippincott Williams & Wilkins, 1990.
2. Benzel E. Biomechanics of Spine Stabilization. American Association of Neurological Surgeons (distributed by Thieme New York), 2001.
3. Morlock MM, Bonin V, Deuretzbacher G, Müller G, Honl M, Schneider E. “Determination of the in vivo loading of the lumbar spine with a new approach directly at the workplace – first results for nurses.” Clin Biomech 2000, 15(8): 549-558.
4. Bible JE, Biswas D, Miller CP, Whang PG, Grauer JN. “Normal functional range of motion of the lumbar spine during 15 activities of daily living.” J Spinal Disord Tech. 2010, 23(2): 106-112.