The influence of subgroup diagnosis on radiographic and clinical outcomes after lumbar fusion for degenerative disc disorders revisited: a systematic review of the literature.
Understanding the influence of preoperative diagnosis on outcomes for lumbar fusion surgery improves the quality of research and outcomes data, and helps guide treatment decisions.



We sought to perform a systematic review of the literature published between 2000 and 2014 regarding lumbar fusion outcomes for degenerative disorders. An assessment of the influence of subgroup diagnosis on outcomes as well as the quality of this body of literature was performed.



Systematic review PATIENT SAMPLE: The 100 studies ultimately included involved adult patients (n=8,706) undergoing fusion surgery for degenerative disorders of the lumbar spine.



Visual analog scale (VAS) pain scores, complication rates, and determination of successful fusion METHODS: With adherence to the PRISMA guidelines, electronic searches were performed through PubMed, Scopus, and Web of Science to identify all studies involving lumbar fusion for degenerative disc disorders from January 2000 to August 2014. Studies were eligible for inclusion if they addressed adult patients treated with lumbar fusion for one of the following: stable degenerative disc disease, unstable degenerative disc disease, degenerative disc disease not specified (DDDns), herniated disc (DH), degenerative spondylolisthesis (DDDsp), and adult degenerative scoliosis (DDDsc). Abstracted data included the number of patients, preoperative diagnosis, fusion technique, complications, fusion rate, and clinical outcomes.



One hundred articles met inclusion criteria and yielded data for 8,706 patients. Forty-three studies included data for clinical improvement (VAS scores). The mean clinical improvement in VAS scores was significantly different among the diagnoses (p<.001), with DDDsp demonstrating the highest improvement (60%) and DDDns having the lowest (45%). Eighty-five studies included data for complication rates. Complication rates differed significantly (p<.001), with the highest rate seen in the DDDsc group (18%), followed by DDDsp (14%). Seventy-eight studies included data for fusion. The pooled odds of fusion for prospective studies were 6.93 (95% CI 4.75, 10.13). There was no evidence of publication bias.



A relationship between outcomes and subgroup diagnosis was demonstrated. This review demonstrated a higher quality of evidence in the literature, and greater overall fusion rates compared to similar studies published in the 1980s and 1990s.
Department of Orthopaedic Surgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
Amandeep
A
Bhalla
Department of Orthopaedic Surgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA. Electronic address: ajschoen@neomed.edu.
Andrew J
AJ
Schoenfeld
Department of Orthopaedic Surgery, Harbor UCLA Medical Center, Los Angeles, CA, USA.
Jaiben
J
George
Orthopaedic Specialists of Austin, Austin, TX, USA.
Michael
M
Moghimi
Department of Orthopaedic Surgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
Christopher M
CM
Bono
D000328:Adult; D005260:Female; D006801:Humans; D055959:Intervertebral Disc Degeneration / Q000000981:diagnostic imaging / Q000601:surgery*; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging / Q000601:surgery; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000000981:diagnostic imaging* / Q000453:epidemiology; D011859:Radiography; D013123:Spinal Fusion / Q000009:adverse effects* / Q000379:methods; D016896:Treatment Outcome
Complications; Degenerative disease; Fusion; Lumbar fusion; Outcomes; Rate; Spondylolisthesis