The L4 and L5 are the two lowest vertebrae of the lumbar spine.
These vertebrae are very strong cylindrical bones, and they form the roof (L4) and floor (L5) of the cushion (disc) that sits between them.
The L4 -5 spinal motion segment is prone to degeneration over time.
The bottom segments of the spine bear the weight of the upper body, communicate motion to the hips, and allow a wide range of motion in the back to allow bending and twisting.
The weight load and mobility of this area makes the segment susceptible to developing pain from injury and/or degenerative changes from repetitive stresses over time.
A problem at the L4-5 segment is a common cause of sciatica.
This spinal motion segment includes a a pair of nerve roots that exit through a boney opening in the back of the spine. Compression or inflammation of this nerve is commonly caused by boney growth into the nerve passage that causes it to narrow, a slipped disc that can inflame the nerve root and/or compress it, or when L4 slips forward on L5 (spondylolisthesis). The narrowing and inflammation that these common problems cause can result in sciatica (pain down the leg or legs). Symptoms may radiate down the leg causing pain, numbness, and/or weakness, foot drop, and more severe problems can cause difficulty walking.
L4-L5 issues can also lead to hip pain and stiffness.
Common conditions — such as a lumbar herniated disc, degenerated disc, spinal stenosis, or spondylolisthesis can cause problems with the spinal nerve at this level that extends to the hips. If you have hip pain, it may actually be coming from your back.
Buttock pain is a hallmark symptom of a problem at the L4-L5 lumbar motion segment.
Pain that radiates into the buttock often points to a problem at the L4-L5 level. The buttock pain may be sharp, burning, or a deep ache. It is usually felt on one side but may occur on both sides. Frequently the pain radiates past the buttock down into the leg.
The nerve inside the L4-L5 vertebral endplates may also cause low back pain.
The nerve just inside each vertebral endplate is called the basivertebral nerve. When this nerve is diagnosed as the source of pain it is called vertebrogenic pain, meaning that the vertebra at that spinal level is the source of the pain. It typically causes chronic low back pain that does not radiate into the leg.
The L4-L5 spinal motion segment is also subject to many additional causes of pain, including osteoarthritis, synovial cysts and other boney growths.
If you’re dealing with chronic leg and/or back pain and considering spine surgery, it’s worth asking whether a motion-preserving option is available to you from the start, and if fusion is the recommendation, why that’s the case. If you’ve already had a spine procedure and you’re facing a second surgery, the question becomes whether that next level could be treated in a way that preserves mobility and function.
Why do Patients Seek Artificial Disc Replacement in Germany?
International patients frequently travel to specialized spine centers in Germany to access advanced motion-preserving spine surgery alternatives to conventional spinal fusion.
Key clinical differentiators include:
- Multi-Level Approaches: Routine performance of multi-level lumbar (L4-L5, L5-S1) and cervical disc arthroplasty.
- Prosthetic Technology: Access to next-generation viscoelastic and unconstrained disc prosthetics (e.g., M6-L, M6-C, ProDisc-L, LP-ESP, activL).
- Anterior Retroperitoneal Exposure: Muscle-sparing anterior lumbar approaches designed to preserve posterior musculature and reduce adjacent segment disease (ASD).
About Dr. Karsten Ritter-Lang: Motion Preservation & Spine Arthroplasty
Dr. Karsten Ritter-Lang is recognized internationally for his clinical focus on intervertebral disc prosthetics and complex spinal reconstruction.
- Surgical Experience: Over 30 years dedicated to motion-preserving spinal procedures, having performed thousands of cervical and lumbar artificial disc replacements.
- Academic Lineage: Trained directly under Prof. Dr. Kurt Schellnack and Dr. Karin Büttner-Janz at the Charité University Hospital in Berlin—the pioneering research team that developed the original Charité artificial disc prosthesis.
- Clinical Focus: Multi-level lumbar disc replacement, motion-preserving reconstruction for degenerative disc disease, and alternatives to spinal fusion.
Remote Consultations & International MRI Reviews
For patients seeking preliminary assessments or second opinions regarding total disc replacement and spinal stenosis treatments:
- Better Disc Replacement: Detailed comparative guides on motion preservation vs. spinal fusion, clinical indications for lumbar total disc replacement (TDR), and multi-level case analyses.
BetterDiscReplacement
- Stenum Hospital International Patient Portal: Preliminary remote MRI evaluations, international intake protocols, and surgical technology overviews for European and overseas patients
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