Is the Goutallier grade of multifidus fat infiltration associated with adjacent-segment degeneration after lumbar spinal fusion?

J Neurosurg Spine 34:190–195, 2021

The aim of this study was to investigate whether fat infiltration of the lumbar multifidus (LM) muscle affects revision surgery rates for adjacent-segment degeneration (ASD) after L4–5 transforaminal lumbar interbody fusion (TLIF) for degenerative spondylolisthesis.

METHODS A total of 178 patients undergoing single-level L4–5 TLIF for spondylolisthesis (2006 to 2016) were retrospectively analyzed. Inclusion criteria were a minimum 2-year follow-up, preoperative MR images and radiographs, and single-level L4–5 TLIF for degenerative spondylolisthesis. Twenty-three patients underwent revision surgery for ASD during the follow-up. Another 23 patients without ASD were matched with the patients with ASD. Demographic data, Roussouly curvature type, and spinopelvic parameter data were collected. The fat infiltration of the LM muscle (L3, L4, and L5) was evaluated on preoperative MRI using the Goutallier classification system.

RESULTS A total of 46 patients were evaluated. There were no differences in age, sex, BMI, or spinopelvic parameters with regard to patients with and those without ASD (p > 0.05). Fat infiltration of the LM was significantly greater in the patients with ASD than in those without ASD (p = 0.029). Fat infiltration was most significant at L3 in patients with ASD than in patients without ASD (p = 0.017). At L4 and L5, there was an increasing trend of fat infiltration in the patients with ASD than in those without ASD, but the difference was not statistically significant (p = 0.354 for L4 and p = 0.077 for L5).

CONCLUSIONS Fat infiltration of the LM may be associated with ASD after L4–5 TLIF for spondylolisthesis. Fat infiltration at L3 may also be associated with ASD at L3–4 after L4–5 TLIF.

Four-year results of a prospective single-arm study on 200 semi-constrained total cervical disc prostheses


J Neurosurg Spine 25:556–565, 2016

Recent studies have described encouraging outcomes after cervical total disc replacement (cTDR), but there are also critical debates regarding the long-term effects of heterotopic ossification (HO) and the prevalence of adjacent-level degeneration. The aim in this paper was to provide 4-year clinical and radiographic outcome results on the activ C disc prosthesis.

Methods A total of 200 subjects underwent single-level activ C (Aesculap AG) implantation between C-3 and C-7 for the treatment of symptomatic degenerative disc disease. Clinical and radiographic assessments were performed preoperatively, intraoperatively, at discharge, and again at 6 weeks, 6 months, 1 year, 2 years, and 4 years. Radiographic evaluations were done by an independent core laboratory using a specific software for quantitative motion analysis.

Results Neck Disability Index (NDI) and visual analog scale (VAS) score for neck and arm pain decreased significantly from baseline to the 4-year follow-up. The mean improvement for NDI was 20, for VAS severity and frequency of neck pain 26.4 and 28, and for VAS severity and frequency of arm pain 30.7 and 35.1, respectively. The neurological situation improved for the majority of patients (86.4%); 76.1% of cases were asymptomatic. Subsequent surgical interventions were reported in 7% of the cases, including device removals in 3%. In 2.5% a subsidence greater than 3 mm was recorded; 1 of these cases also had a migration greater than 3 mm. No device displacement, expulsion, disassembly, loose or fractured device, osteolysis, or facet joint degeneration at the index level was observed. Segmental lordotic alignment changed from -2.4° preoperatively to -6.2° at 4 years, and postoperative height was maintained during the follow-up. Advanced HO (Grade III and IV) was present in 27.1% of the cases; 82.4% showed segmental mobility. A progression of radiographic adjacent-segment degeneration occurred in 28.2%, but only 4.5% required surgical treatment.

Conclusions The activ C is a safe and effective device for cervical disc replacement confirming the encouraging results after cTDR.

Incidence of Adjacent Segment Disease Requiring Reoperation After Lumbar Laminectomy Without Fusion


Neurosurgery 78:192–199, 2016

Adjacent segment disease (ASD) has not been described after laminectomy without fusion.

OBJECTIVE: To determine the incidence of ASD after a 1- or 2-level lumbar laminectomy.

METHODS: We retrospectively reviewed medical records of all patients who underwent 1- or 2-level, bilateral lumbar laminectomy without fusion for degenerative spinal disease (all follow-up $1 year). ASD was defined as clinical and/or radiographic evidence of degenerative spinal disease that required reoperation at the level above or below the index laminectomy.

RESULTS: Of the 398 patients, the incidence of ASD requiring reoperation was 10%. The 39 ASD cases were almost equally distributed at L2-L3 (31%), L3-L4 (26%), and L5-S1 (31%), and to a lesser extent at L4-L5 (15%) (P = .51). The ASD incidences of 10% and 9% were equivalent after a 1- and 2-level laminectomy, respectively (P = .76). Rostral ASD was statistically more common than caudal ASD after both the 1- (P , .001) and 2- (P , .001) level laminectomy. Of the 39 ASD cases, 95% required laminectomy, 26% discectomy, and 49% fusion. Average time to ASD was 4 years. After a Kaplan-Meier analysis, time to reoperation for ASD was equivalent among the 1- and 2-level laminectomy cohorts (log-rank test, P = .13).

CONCLUSION: The cumulative incidence of ASD requiring reoperation was 10% over a mean of 4 years. Both the 1- and 2-level laminectomy cohorts experienced equivalent incidences and rates of ASD. Of the 39 operations for ASD, about half required a fusion.

Is inclusion of the occiput necessary in fusion for C1–2 instability in rheumatoid arthritis?

Is inclusion of the occiput necessary in fusion for C1–2 instability in rheumatoid arthritis?

J Neurosurg Spine 18:50–56, 2013

The atlantoaxial joint is the location most and earliest affected in patients with rheumatoid arthritis (RA). In longstanding disease, ligamentous and osseous destruction can progress and involve all cervical segments. If surgical intervention is necessary, some prefer, to be safe, undertaking fusion to the occiput, whereas others advocate 1-level fusion of C1–2. Sparing the occiput (Oc)–C1 segment would allow retention of a considerable amount of physiological range of motion and seems beneficial against subaxial overload. Previous clinical studies on this topic have provided only nonspecific data after short-term follow-up, rendering a segment-sparing approach questionable. The purpose of the present investigation was to assess long-term progression of inflammatory or degenerative destruction in the Oc–C1 segment after isolated C1–2 fusion for RA.

Methods. In a series of 113 consecutive patients with RA-related destruction restricted to the craniocervical junction, 14 individuals underwent Oc–C2 fusion and 99 underwent surgery exclusively at the C1–2 level. After a mean follow-up period of 9.4 years (range 4.9–14.7 years), 46 patients were available for clinical and radiographic examination, including CT imaging.

Results. None of the 46 patients needed additional surgery to extend the fusion to the occiput. Despite marked deterioration in the subaxial cervical spine, in general there were little or no changes in the atlantooccipital region. All but one patient presented with bony fusion of the fixed C1–2 level at follow-up.

Conclusions. The results of this investigation suggest that if the Oc–C1 joint is free of osseous destructions on conventional radiographs and free of abnormalities on MRI scans at the time of surgery (for transarticular fixation and fusion of C1–2), there is a very low risk for relevant destruction in the following 5–14 years. Thus, no prophylactic oligosegmental approach, but rather a segment-sparing monosegmental approach, is preferred, even in patients with high inflammatory levels.

Dynamic stabilization adjacent to single-level fusion: Part II. No clinical benefit for asymptomatic, initially degenerated adjacent segments after 6 years follow-up

Eur Spine J (2010) 19:2181–2189 DOI 10.1007/s00586-010-1517-4

Progression of degeneration is often described in patients with initially degenerated segment adjacent to fusion (iASD) at the time of surgery. The aim of the present study was to compare dynamic fixation of a clinically asymptomatic iASD, with circumferential lumbar fusion alone.

60 patients with symptomatic degeneration of L5/S1 or L4/L5 (Modic C 2) and asymptomatic iASD (Modic = 1, confirmed by discography) were divided into two groups. 30 patients were treated with circumferential single-level fusion (SLF). In dynamic fixation transition (DFT) patients, additional posterior dynamic fixation of iASD was performed. Preoperatively, at 12 months, and at a mean follow-up of 76.4 (60–91) months, radiological (MRI, X-ray) and clinical (ODI, VAS, satisfaction) evaluations assessed fusion, progression of adjacent segment degeneration (PASD), radiologically adverse events, functional outcome, and pain.

At final follow-up, two nonfusions were observed in both groups. 6 SLF patients and 1 DFT patient presented a PASD. In two DFT patients, a PASD occurred in the segment superior to the dynamic fixation, and in one DFT patient, a fusion of the dynamically fixated segment was observed. 4 DFT patients presented radiological implant failure. While no differences in clinical scores were observed between groups, improvement from pre-operative conditions was significant (all p<0.001). Clinical scores were equal in patients with PASD and/or radiologically adverse events. We do not recommend dynamically fixating the adjacent segment in patients with clinically asymptomatic iASD. The lower number of PASD with dynamic fixation was accompanied by a high number of implant failures and a shift of PASD to the superior segment.

Radiologically documented adjacent-segment degeneration after cervical arthroplasty

Surgical Neurology 72 (2009) 325–329. doi:10.1016/j.surneu.2009.02.013

Background: The authors retrospectively studied the incidence and characteristics of radiologically documented adjacent-segment degeneration after single-level diskectomy and subsequent cervical arthroplasty using the Bryan (Medtronic Sofamor Danek; Memphis, TN) disk prosthesis.

Methods: Seventy-two patients with single-level arthroplasty using the Bryan cervical disk prosthesis were evaluated. Radiological evidence of adjacent-disk disease included new formation or enlargement of anterior osteophyte, new or increasing ALL calcification, or narrowing of disk space documented on serial plain radiographs. We reported the characteristics of adjacent-segment degeneration and reviewed all of the cases.

Results: Among the 72 patients, 9 patients (12.5%) showed radiological evidence of adjacentsegment degeneration. The mean age was 43.3 years old, with a male-female ratio 1:3. The mean follow-up period was 24.2 (12.1-35.9) months. The mean period of onset was 16.3 months. Uppersegment degeneration was documented in 4 cases (3 new osteophyte, 1 enlargement of osteophyte), whereas lower-segment degeneration was noted in 5 cases (1 new osteophyte, 3 enlargement of osteophyte, 1 decreased disk height). Among the degenerated cases, 4 cases (44.4%) also showed various degrees of HO.

Conclusions: The rate of adjacent-segment degeneration was higher than that observed in previous studies. Adjacent-segment degeneration documented a tendency toward HO. A longer follow-up period is necessary to investigate and document the different types of degeneration seen at levels adjacent to artificial Bryan cervical disk prostheses.