This is a prospective, single-arm, open-label, non-randomized study. The aim of the study is to assess the safety and efficacy of the Prow LIF procedure in Transforaminal Lumbar Interbody Fusion (TLIF) procedures for the treatment of subjects with symptomatic degenerative disc disease (DDD).

Primary endpoints:

• Safety: Incidence of device-related anticipated and unanticipated serious adverse events (SAE). However, ALL complications and adverse events (AE) will be monitored and recorded.
• Primary radiographic effectiveness outcome parameter: evaluations of fusion rate.

Inclusion Criteria:main Inclusion Criteria

1. Male and female between 18-65 years of age (skeletally mature).

2. Subjects suffering from degenerative disc disease (DDD) accompanied by back pain with leg pain at a single level between L2 and S1 confirmed by history and radiographic studies and that are scheduled for a fusion operation. DDD is determined to be present if one or more of the following are noted:

   1. instability (defined as angulation ≥ 5° and/or translation ≥ 4mm on flexion/extension radiographs);
   2. osteophyte formation;
   3. decreased disc height;
   4. ligamentous thickening;
   5. disc degeneration/herniation; or
   6. facet joint degeneration.

3. A pre-op Oswestry Low Back Pain Disability Questionnaire (ODI) score of 35 % or more;

4. Be non-responsive to non-operative treatment for at least 6 months;

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Exclusion Criteria:

1. The Antero-Posterior (AP) diameter (at midline) of the involved level is <31mm.

2. Any previous spinal surgery at the involved level;

3. Spondylolisthesis > grade I;

4. Ankylosed segment at the affected level;

5. History or radiographic evidence of osteoporotic fractures in the spine;

6. Paraparesis;

7. Progressive neurologic conditions;

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