Journal of Spine

Introduction: Minimally invasive lateral lumbar interbody fusion (MIS LLIF) been shown to minimize soft tissue dissection and blood loss in comparison to open posterior lumbar interbody fusion. This study describes the clinical and radiographic outcomes of patients treated with expandable interbody spacers with adjustable lordosis for MIS LLIF.
Methods: Single surgeon retrospective Institutional Review Board-exempt chart review on 57 consecutive patients who underwent MIS LLIF at 1–2 contiguous level(s) using expandable spacers with adjustable lordosis, which allow for expansion in height and lordosis. Radiographic and clinical functional outcomes were collected and compared at preoperative and postoperative time points up to 12 months. Statistical results were significant if P<0.05.
Results: Fifty-seven consecutive patients were evaluated with an average age of 58 ± 12.3 years, and 49.1% were female. Visual Analog Scale (VAS) for back pain and Oswestry Disability Index (ODI) scores decreased significantly at 12 months. Lumbar lordosis improved by a mean of 5.1° at 12 months (P<0.001). Anterior, middle, and posterior disc height significantly increased at 12 months by means of 5.2 mm, 4.6 mm, and 2.6 mm respectively (P<0.001). Neuroforaminal height increased by a mean of 3.7 mm (P<0.001) while segmental lordosis improved by 3.7° at 12 months.
Discussion and Conclusion: This study showed significant positive clinical and radiographic outcomes for patients who underwent MIS LLIF using expandable interbody spacers with adjustable lordosis based on decreased VAS back pain and ODI scores at 1-year follow-up. The use of expandable spacers with adjustable lordosis was shown to be safe and effective for the cohort studied.

Background: Expandable integrated titanium interbody spacers have been introduced in recent years for use in minimally invasive lateral lumbar interbody fusion (MIS LLIF) procedures. These devices offer in situ expansion that enables them to conform to intervertebral anatomy with potentially less endplate disruption and greater indirect decompression. This study describes the radiographic outcomes in patients who underwent MIS LLIF using titanium expandable interbody spacers with an integrated plate.

Method: This is a single-surgeon, retrospective, Institutional Review Board-exempt chart review conducted from June 2015 to December 2017 on consecutive patients diagnosed with spondylolisthesis who underwent MIS LLIF at 1–2 contiguous level(s) using a lateral integrated titanium expandable interbody spacer. Radiographic outcomes were collected and compared from preoperative to postoperative at 2 and 6 weeks, 3, 6, 9, and 12 month follow-ups. Statistical results were significant when P<0.05.

Results: Seventeen consecutive patients were evaluated with an average age of 69.2 ± 7.9 years (range: 51–82 years), and 58.8% were female. Mean anterior disc height significantly improved from baseline by 68.3% (7.7 ± 4.5 mm), 58.4% (6.9 ± 5.0 mm), 59.4% (7.0 ± 4.6 mm), 56.4% (6.1 ± 5.0 mm), 52.5% (5.7 ± 4.8 mm), and 51.5% (4.2 ± 4.0 mm) at 2 and 6 weeks, 3, 6, 9, and 12, months, respectively (P<0.001). Mean posterior disc height significantly improved from baseline by 78.0% (4.9 ± 2.9 mm), 67.8% (4.3 ± 2.9 mm), 66.1% (4.3 ± 2.9 mm), 69.5% (4.3 ± 3.0 mm), 57.6% (3.8 ± 2.7 mm), and 61.0% (3.2 ± 2.5 mm) at 2 and 6 weeks, 3, 6, 9, and 12, months, respectively (P<0.001). Segmental and lumbar lordosis remained consistent at all postoperative time points (P>0.05).

Conclusion: This study showed significant positive radiographic outcomes for patients who underwent MIS LLIF using novel integrated titanium expandable interbody spacers, based on significant post-operative changes in intervertebral lordosis and anterior and posterior disc height observed through 12-month follow-up.

Purpose: A disease specific Brace Questionnaires (BrQ) has been developed for measuring the quality of life of patients with adolescent idiopathic scoliosis (AIS) who were under brace treatment. The aim of this study was to translate and validate the Chinese version of BrQ from its original Greek version.

Methods: Forward and backward translations of BrQ were performed according to the cross-cultural adaptation process. After translation, 120 subjects with AIS were recruited and asked to fill out the Chinese translated BrQ and the Chinese refined 22-item Scoliosis Research Society questionnaire (SRS-22r). Subjects completed the Chinese translated BrQ again in 1-2 weeks. Demographic data as well as other parameters were collected such as brace wearing duration, brace wearing hours per day (self-reported), in-brace Cobb angles and curve patterns. The reliability and validity were checked by internal consistency and test-retest reliability using Cronbach’s alpha, Intraclass correlation as well as Pearson correlation coefficient.

Results: The internal consistency and test-retest reproducibility of the translated BrQ were 0.89 and 0.83 respectively. The Chinese translated BrQ demonstrated concurrent validity as reflected by the significant correlation between the BrQ domains and the relevant SRS-22r domains. The Chinese translated BrQ showed its discriminant validity too. Significant differences were found in the BrQ school activity mean score (p=0.042) and social functioning mean score (p=0.047) between subject groups: age 12 or below and age 13 or above. Significant differences were also detected in the BrQ domain score including physical functioning (p<0.001), emotional functioning (p=0.002), vitality (p=0.004), bodily pain (p<0.001) and social functioning (p=0.018) between subject groups with different brace wearing hours (0-8 hours, 9-16 hours and 17-23 hours).

Conclusion: The Chinese translated BrQ showed good validity and reliability. It demonstrated its concurrent validity and discriminatory validity in the AIS population studied.

Introduction: Sagittal spino-pelvic instability is the most common cause for chronic low back pain. Legaye stated that the pelvic incidence (PI) is an anatomical parameter for assessing spinal stability. Pelvic incidence can be calculated by adding pelvic tilt and sacral slope. Sacral table angle (STA) is the angle between the superior sacral endplate and the trailing edge line of sacrum.

Objective: To prove the temporal association of pelvic incidence and sacral table angle and lumbar instability in patients with chronic low back pain.

Materials and methods: A total of 191 cases with nonspecific low back pain with or without lumbar instability were analysed with spinal radiographs. The pelvic incidence and sacral table angle were calculated for L3 – L4, L4 – L5 and L5 – S1 levels.

Results: Out of 191 cases, the levels of L5 – S1 cases showed 5% translation and 10° angulation. We observed a significantly statistical difference between two groups in terms of pelvic incidence (p=0.01) and sacral table angle (p<0.01). The lumbar instability of L5 – S1 segment is associated with lower pelvic incidence and increased sacral table angle. The Spearman’s Rank correlation coefficient (rho ρ) for the study was 0.745 which imply highly positive correlation between pelvic incidence and sacral table angle and lumbar instability.

Conclusion: The spino-pelvic parameters influence the evolution of spinal degenerative disease. We observed that the patients with chronic low back pain without lumbar instability showed normal or decreased PI and increased STA whereas patients with chronic low back pain with lumbar instability showed increased PI and decreased STA. The cases with increased PI and decreased STA are prone to develop degenerative spinal pathology or discogenic pathology which alters the postural balance of spinal column.

Objectives: To present an awake, fully endoscopic surgical approach for treating radiculopathy that results from L5/ S1 foraminal stenosis in a patient who had prior interbody fusion and posterolateral fusion.

Methods: The patient underwent an awake, endoscopic decompression procedure utilizing two different sized cannula and high-speed drill system under direct visualization. Fully endoscopic revision laminotomy was done first through contralateral interlaminar approach. This was followed by endoscopic inside-out foraminotomy.

Results: The operative time was 108 minutes, estimated blood loss was negligible, and the surgery was done as outpatient. There were no intraoperative or postoperative complications. Comparison of preoperative and final clinical metrics demonstrated that Oswestry Disability Index (ODI) improved from 56 to 28. VAS-L improved from 8 to 2. The ODI and VAS-B scores at the last follow-up showed 73% and 78% improvement from the preoperative period respectively, which showed a satisfactory clinical outcome after 1-year follow-up and did not induce postoperative segmental spinal instability.

Conclusion: Fully endoscopic contralateral laminotomy and inside-out lumbar foraminotomy is a safe, effective technique for addressing lumbar foraminal stenosis, especially for patients with lumbar foraminal stenosis that are difficult for ipsilateral transforaminal approach.