Analysis of risk factors for non-fusion of bone graft in anterior cervical discectomy and fusion: A clinical retrospective study.

BACKGROUND: Bone graft fusion is a major concern among surgeons after Anterior Cervical Discectomy and Fusion (ACDF) surgery as non-fusion may lead to further physical and drug therapies. METHODS: The related risk elements of non-fusion of bone graft in ACDF surgery were retrospectively assessed. Patients receiving ACDF operation in our hospital from January 2015 to December 2019 were retrospectively analyzed. According to the criteria, 107 study subjects were recruited with a total of 164 surgical segments. The general information of patients, bone graft materials, imaging parameters, and clinical efficacy was recorded. T-test, chi-square test and binary logistic regression evaluation were employed to explore the risk factors of bone graft nonunion. RESULTS: Low housefield unit (HU) value, diabetes, allogeneic bone, and hydroxyapatite (HA) artificial bone could be risk factors for bone graft fusion in ACDF surgery. Further multivariate analysis was performed and confirmed those related factors of bone graft non-fusion including low HU value (non-fusion rate: 32.53% [27/83], OR = 5.024, p = 0.025), diabetes (non-fusion rate: 53.33% [8/15], OR = 4.776, p = 0.031), allogeneic bone (18.57% [13/70], OR = 3.964, p = 0.046), and artificial bone (68.29% [28/41], OR = 50.550, p < 0.01). CONCLUSION: By looking at bone graft fusion, selecting autologous iliac bone is an ideal selection to avoid non-fusion of bone graft in ACDF. Diabetes was more important predictor of bone graft nonunion than low HU value. Larger sample size and longer follow-up are required to further confirm these findings in the future.

Preliminary outcomes of allograft and hydroxyapatite as substitutes for autograft in anterior cervical discectomy and fusion with self-locking standalone cages.

PURPOSE: To investigate the efficacy and safety of allograft and hydroxyapatite (HA) as substitutes for autograft in anterior cervical discectomy and fusion (ACDF). METHODS: In this study, 49 patients (80 segments) treated with ACDF were included and allocated into three groups [group A, autogenous iliac bone, n = 18; group B, allogeneic bone, n = 16; group C, HA, n = 15]. The clinical efficacy and fusion status were compared among each group. Complications were recorded in detail, and the Bazaz classification and Voice Handicap Index-10 (VHI-10) were used to detect dysphagia and dysphonia. RESULTS: Patients exhibited similar clinical efficacy among the groups during the final follow-up. All patients in groups A and B achieved fusion compared to only 73.3% of patients in group C. Groups A and B had similar fusion score, both of which greater than that of group C. No cage subsidence was observed in group A; however, 6.3% of patients in group B and 53.3% in group C had cage subsidence. Two patients in group A (11.1%) had persistent pain at the donor site. One patient in group B had dysphagia and dysphonia (6.3%), while one patient in group C had dysphonia (6.7%). CONCLUSION: In ACDF, the autogenous iliac bone was the most ideal bone graft. The allogeneic bone was an acceptable substitute but risked cage subsidence and dysphagia. HA had a much lower fusion rate and a high risk of cage subsidence. Better substitutes should be further explored for ACDF.

The Anatomical Study and Clinical Significance of the Sinuvertebral Nerves at the Lumbar Levels.

STUDY DESIGN: A dissection-based study of 10 embalmed human cadavers. OBJECTIVE: The purpose of this study was to describe the sinuvertebral nerves at the lumbar level and to discuss their possible clinical significance. SUMMARY OF BACKGROUND DATA: Discogenic low-back pain is mediated by the sinuvertebral nerves. However, the detailed descriptions of the sinuvertebral nerves at the lumbar level are lacking. METHODS: One hundred L1-L5 intervertebral foramina from 10 embalmed cadavers were studied. The presence of the sinuvertebral nerves was noted. The quantity, origin, pathway, innervation range, and spatial orientations of the sinuvertebral nerves in the L1-L5 intervertebral foramina were examined. RESULTS: A total of 450 sinuvertebral nerves were identified in the 100 lumbar intervertebral foramina; sinuvertebral nerves were observed in 100.00% of the intervertebral foramina. The sinuvertebral nerves were routinely divided into the following two types: the sinuvertebral nerve deputy branch and sinuvertebral nerve main trunk. Three hundred twelve sinuvertebral nerve deputy branches were found; on average, there were approximately 3.12 (range, 1-8) branches in each intervertebral foramen. One hundred thirty-eight sinuvertebral nerve main trunks were found, and sinuvertebral nerve main trunks were observed in 97.00% of the intervertebral foramina. The initial portion of the sinuvertebral nerve was located along the posterior-lateral edge of the disc to the spinal canal. Sixty-one (44.20%) sinuvertebral nerve main trunks originated from the starting point of the gray ramus communicans of the nerve root; 77 (55.80%) sinuvertebral nerve main trunks originated from the anterior surface of the spinal ganglia of the nerve root. CONCLUSION: This is a systematic anatomy study that describes the sinuvertebral nerve at the lumbar level and may be of clinical importance to spinal surgeons. A comprehensive understanding of the distribution of sinuvertebral nerves may lead to significant benefits for patients undergoing percutaneous endoscopic treatment for discogenic low-back pain. LEVEL OF EVIDENCE: 4.