title: Two-level lumbar total disc replacement: functional outcomes and segmental motion after 4 years.
abstract: BACKGROUND
  Lumbar total disc replacement is an effective treatment for single-level discogenic lower back pain. But the replacement of two disc levels is controversial.
  
  
  OBJECTIVE
  Two-level total disc replacement will improve function while preserving spinal motion.
  
  
  METHODS
  A continuous series of 108 patients (51 women, 57 men) surgically treated over two levels with the ProDisc-L implant (Synthes Spine) was evaluated retrospectively with an average follow-up of 4 years. Ninety-three of these patients were operated for L4/L5 and L5/S1 degenerative disc disease, while 15 were operated for L3/L4 and L4/L5 disease. The procedure was carried out through the left retroperitoneal approach in 65 patients, the right retroperitoneal approach in 42 patients and both approaches in 1 patient. The Oswestry score, lumbar VAS and radicular VAS were used to evaluate function. The motion of the prosthetic disc segments was evaluated using Cobb's method. Data were collected prospectively in the context of regular patient monitoring. A retrospective analysis was carried out by an independent examiner.
  
  
  RESULTS
  The procedure led to a statistically significant improvement in the functional scores. The motion of the upper disc segment was 9° (0°-19°) in flexion/extension and 5.5° (2°-12°) in lateral bending. It was 6.2° (0°-14°) and 1.9° (0°-7°) at the lower disc segment. The range of motion was similar in L3/L4 and L4/L5, but was less in L5/S1. Lack of mobility was not correlated with alterations in the functional outcome. The complication rate was 18%.
  
  
  CONCLUSIONS
  Two-level lumbar disc replacement improves spinal function while preserving its mobility. But this procedure is fraught with risks and must be carried out by a highly-experienced team. A longer follow-up is needed to evaluate the sustainability of the results and to detect any adjacent segment disease. The French National Authority for Health (HAS) has recommended against two-level lumbar disc replacement, so it no longer can be performed in France.
authors.affiliation: Hôpital privé « les Franciscaines », 3, rue Jean-Bouin, 30032 Nîmes, France; 65, avenue Jean-Jaurès, 30900 Nîmes, France. Electronic address: sebastien.trincat@yahoo.fr.
authors.forename: S
authors.initials: S
authors.lastname: Trincat
authors.affiliation: Clinique du Parc, 50, rue Emile-Combe, 34170 Castelnau-le-Lez, France.
authors.forename: G
authors.initials: G
authors.lastname: Edgard-Rosa
authors.affiliation: Clinique du Parc, 50, rue Emile-Combe, 34170 Castelnau-le-Lez, France.
authors.forename: G
authors.initials: G
authors.lastname: Geneste
authors.affiliation: Clinique du Parc, 50, rue Emile-Combe, 34170 Castelnau-le-Lez, France.
authors.forename: T
authors.initials: T
authors.lastname: Marnay
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D005500:Follow-Up Studies; D005602:France; D006801:Humans; D055959:Intervertebral Disc Degeneration / Q000601:surgery*; D017116:Low Back Pain / Q000601:surgery; D008159:Lumbar Vertebrae / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D009068:Movement; D063868:Patient Outcome Assessment; D016059:Range of Motion, Articular; D012189:Retrospective Studies; D059145:Total Disc Replacement; D064232:Visual Analog Scale; D055815:Young Adult
keywords: Degenerative disc disease; Low-back pain; Total disc replacement