Single-Level Endoscopic TLIF Has Decreased Surgery Duration, Blood Loss, and Length of Hospital Stay While Achieving Similar 1-Year Clinical and Radiological Outcomes Compared With Conventional Minimally Invasive TLIF.

BACKGROUND: This study presents a single surgeon's experience comparing 1-year outcomes of endoscopic transforaminal lumbar interbody fusion (E-TLIF) vs minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) in an Asian population. METHODS: Retrospective review of consecutive patients who underwent single-level E-TLIF or MIS-TLIF by a single surgeon in a tertiary spine institution from 2018 to 2021 with 1-year follow-up. Inclusion criteria for both procedures were degenerative disc disease with grade I or II spondylolisthesis and mild to moderate central canal stenosis. Clinical outcomes assessed included surgery duration, blood loss, and length of stay. Patient-reported outcomes assessed included the visual analog score for back pain and lower limb pain, Oswestry Disability Index, and North American Spine Society Neurogenic Symptom Score. Radiographic parameters assessed included segmental lordosis, posterior disc height, listhesis, and the presence of cage migration or subsidence. RESULTS: Twelve E-TLIF and 34 MIS-TLIF patients were identified. E-TLIF had shorter surgery duration (165 ± 15 vs 259 ± 43 min for E-TLIF and MIS-TLIF groups, respectively; P < 0.001), reduced blood loss (83 ± 75 vs 181 ± 225 mL; P = 0.033), and decreased length of stay (1.8 ± 0.9 vs 4.7 ± 2.9 days; P < 0.001) compared with MIS-TLIF. E-TLIF and MIS-TLIF patients had significant improvements (P < 0.05) at 1 year in all patient-reported outcomes scores and radiographic parameters assessed. Both E-TLIF and MIS-TLIF patient groups also had similar postoperative patient-reported outcomes scores and radiographic parameters. No complications were recorded for E-TLIF, while MIS-TLIF had a case of dura tear and another case of meralgia paresthetica. There were no instances of cage subsidence, cage migration, or implant loosening in either group at 1 year. CONCLUSIONS: Although the study size was limited because E-TLIF is a relatively new technique in our institution, 1-year results demonstrate that E-TLIF can be a safe and efficacious option that achieves clinical and radiological results similar to MIS-TLIF with the additional benefits of decreased surgical duration, blood loss, and length of hospital stay. CLINICAL RELEVANCE: The results of this study support the effectiveness and potential advantages of endoscopic TLIF compared with MIS-TLIF.

Biplanar Expandable Cages for Transforaminal Lumbar Interbody Fusion Are Safe and Achieve Good 1-Year Clinical and Radiological Outcomes in an Asian Population.

BACKGROUND: This study investigated 1-year clinical and radiological outcomes of biplanar expandable (BE) cages following transforaminal lumbar interbody fusion (TLIF) in an Asian population. METHODS: A retrospective review was conducted of all consecutive patients who underwent TLIF with BE cages performed by 2 fellowship-trained spine surgeons from 2020 to 2021. Inclusion criteria included open or minimally invasive (MIS) TLIF, of up to 3 spinal segments, performed for treatment of degenerative disc disease, spondylolisthesis, or spinal stenosis. Patient-reported outcomes, including visual analog score (VAS) for back and lower limb pain, Oswestry Disability Index (ODI) and North American Spine Society neurogenic symptom score (NSS), and various radiographic parameters, were evaluated. RESULTS: A total of 23 patients underwent TLIF with BE cages with a follow-up duration of 1.25 years. Of those patients, 7 (30%) underwent 1-level TLIF, 12 (52%) underwent 2-level TLIF, and 4 (18%) underwent 3-level TLIF, with a total of 43 spinal segments fused. Four patients (17%) underwent MIS TLIF while 19 patients (83%) underwent open TLIF. VAS for back pain scores improved by 4.8 ± 3.4 (P < 0.001) from 6.5 ± 2.6 to 1.7 ± 2.2; VAS for lower limb pain scores improved by 5.2 ± 3.8 (P < 0.001) from 5.7 ± 3.4 to 0.5 ± 1.6; ODI scores improved by 29.0 ± 18.1 (P < 0.001) from 49.4 ± 15.1 to 20.4 ± 14.2; and NSS scores improved by 36.8 ± 22.1 (P < 0.001) from 53.3 ± 21.1 to 16.5 ± 19.8. Significant improvements in radiological parameters included increase in anterior disc height, posterior disc height, foraminal height, segmental lordosis, and lumbar lordosis. There were no implant-related complications, cage subsidence, cage migration, or revision surgery at 1 year. CONCLUSIONS: TLIF performed with BE cages led to significantly improved patient-reported outcomes and radiographic parameters at 1 year and is safe for use in Asians. CLINICAL RELEVANCE: The results of this study support the effectiveness and safety of TLIF with biplanar expandable cages.

Smoking Is Associated With Lower Satisfaction in Nondiabetic Patients Undergoing Minimally Invasive Single-level Transforaminal Lumbar Interbody Fusion.

STUDY DESIGN: This was a retrospective review of prospectively collected registry data. OBJECTIVE: The objective of this study was to investigate the effect of smoking on 2 years postoperative functional outcomes, satisfaction, and radiologic fusion in nondiabetic patients undergoing minimally invasive transforaminal lumbar interbody fusion (TLIF) for degenerative spine conditions. SUMMARY OF BACKGROUND DATA: There is conflicting data on the effect of smoking on long-term functional outcomes following lumbar fusion. Moreover, there remains a paucity of literature on the influence of smoking within the field of minimally invasive spine surgery. METHODS: Prospectively collected registry data of nondiabetic patients who underwent primary single-level minimally invasive TLIF in a single institution was reviewed. Patients were stratified based on smoking history. All patients were assessed preoperatively and postoperatively using the Numerical Pain Rating Scale for back pain and leg pain, Oswestry Disability Index, Short-Form 36 Physical and Mental Component Scores. Satisfaction was assessed using the North American Spine Society questionnaire. Radiographic fusion rates were compared. RESULTS: In total, 187 patients were included, of which 162 were nonsmokers, and 25 had a positive smoking history. In our multivariate analysis, smoking history was insignificant in predicting for minimal clinically important difference attainment rates in Physical Component Score and fusion grading outcomes. However, in terms of satisfaction score, positive smoking history remained a significant predictor (odds ratio=4.7, 95% confidence interval: 1.10-20.09, P=0.036). CONCLUSIONS: Nondiabetic patients with a positive smoking history had lower satisfaction scores but comparable functional outcomes and radiologic fusion 2 years after single-level TLIF. Thorough preoperative counseling and smoking cessation advice may help to improve patient satisfaction following minimally invasive spine surgery. LEVEL OF EVIDENCE: Level III-nonrandomized cohort study.

Cruciate retaining and posterior stabilized total knee arthroplasty in severe varus osteoarthritis knee: A match-pair comparative study in an Asian population.

BackgroundPosterior stabilized (PS) total knee arthroplasty (TKA) is advocated in severe varus osteoarthritic (OA) knees as the posterior cruciate ligament posed challenges in gap balancing. However, there is scarcity in the literature to illustrate the superiority of PS TKA over cruciate retaining (CR) TKA. Our study aims to compare the outcomes between CR and PS TKAs in patients with severe varus OA knees. Methods: A retrospective review was conducted on patients who underwent primary TKA for OA knee from 2003 to 2013. Patients with OA knees of varus tibiofemoral angle ≥15 were matched into two groups (Group CR and PS) according to age, gender, and body mass index and compared in terms of clinical (tibiofemoral alignment, range of motion, and revision rate) and functional outcome (Knee Society Scoring, Oxford Knee Score, Short Form-36 Health Survey). Results: Both Group CR (n = 56) and PS (n = 56) had similar pre-operative scores. Both groups achieved correction of tibiofemoral alignment from median pre-operative varus of 17.6/17.0 (CR/PS) (p = .279) to median post-operative valgus of 4.9/4.0 (CR/PS) (p = .408). Over 24 months, both groups were comparable in achieving significant improvement in clinical and functional outcomes. No case of revision surgery was reported (median follow-up months; CR: 65, PS: 74, p = .549). Conclusion: Both CR and PS TKAs perform similarly well in severe varus OA knee up to 2 years post-operation. Further studies are warranted to assess the long-term outcome between the two implant designs.

Poorer Preoperative Function Leads to Delayed Return to Work After Anterior Cervical Discectomy and Fusion for Degenerative Cervical Myelopathy.

BACKGROUND: The factors that affect return to work (RTW) after anterior cervical discectomy and fusion (ACDF) for degenerative cervical myelopathy (DCM) remain unclear, especially in a non-Workers' Compensation setting. We aimed to (1) identify factors that influence RTW in patients undergoing ACDF (2) determine if early RTW plays a role in functional outcomes, quality of life, and satisfaction. METHODS: Prospectively collected data of 103 working adults who underwent primary ACDF for DCM were retrospectively reviewed. Patients were stratified into 2 groups: early RTW (≤60 days, n = 42) and late RTW (>60 days, n = 61). RESULTS: The mean time taken to RTW was 34.7 and 134.9 days in the early and late RTW groups, respectively (P < 0.001). The early RTW group had significantly better preoperative Japan Orthopaedic Association (JOA) score and Neck Disability Index (NDI) (P < 0.05) and showed a trend toward higher 36-Item Short Form Physical Component Summary (PCS) (P = 0.071). The early RTW group also had significantly better postoperative JOA, NDI, and PCS at 6 months and less arm pain along with a trend toward better NDI at 2 years (P = 0.055). However, there was no difference in the change in outcome scores and a similar proportion in each group attained the minimal clinically important difference for each metric. At 2 years, 85.7% and 77.0% were satisfied in the early and late RTW groups, respectively (P = 0.275). CONCLUSIONS: While working adults that RTW later tend to have poorer function preoperatively and up to 2 years postoperatively, surgeons may reassure them that they will likely experience the same degree of clinical improvement and level of satisfaction after ACDF. LEVEL OF EVIDENCE: Level 3, therapeutic study.

Women Do Not Have Poorer Outcomes After Minimally Invasive Lumbar Fusion Surgery: A Five-Year Follow-Up Study.

BACKGROUND: Women undergoing lumbar spine surgery report greater preoperative pain and disability and have less improvement after surgery. There is a paucity of literature on sex-related differences after minimally invasive surgery transforaminal lumbar interbody fusion (MIS TLIF) surgery. We aim to determine whether sex influences outcome after MIS TLIF at 5-year midterm follow-up. METHODS: Prospectively collected registry data for 907 patients who underwent MIS TLIF at a single institution from 2004 to 2013 were reviewed. Of these, 296 patients (94 males and 202 females) were reviewed at 5-year follow-up. All patients were assessed preoperatively and postoperatively at 2 and 5 years. Data recorded included patient demographics, Oswestry Disability Index (ODI), Short-Form 36 Physical and Mental component scores (SF-36 PCS and MCS), and the North American Spine Society lumbar spine outcome assessment instrument. RESULTS: Females who underwent MIS TLIF were generally younger (females, 52.2 years; males, 56.1 years; P = .04). Females had significantly poorer preoperative ODI (females, 49.5; males, 41.5; P < .001) and SF-36 PCS (females, 31.9; males, 35.6; P < .01) and MCS (females, 44.9; males, 49.2; P < .01) scores. At 2-year and 5-year follow-up, there were no significant differences in ODI, SF-36, and pain scores between sexes. Both groups reported similar proportions that returned to work and returned to function. There were no differences in proportion of patients who were satisfied or had their expectations fulfilled. CONCLUSIONS: Women who undergo MIS TLIF have poorer preoperative function and quality of life than men. However, women demonstrated greater improvement after surgery, attaining similar clinical outcomes at 5-year follow-up. LEVEL OF EVIDENCE: 3.

Predictors of Outcomes After Single-level Anterior Cervical Discectomy and Fusion for Cervical Spondylotic Myelopathy: A Multivariate Analysis.

STUDY DESIGN: This was a retrospective study that was carried out using prospectively collected registry data. OBJECTIVE: The objective of this study was to identify preoperative predictors of outcomes after anterior cervical discectomy and fusion (ACDF) for cervical spondylotic myelopathy. SUMMARY OF BACKGROUND DATA: Proper patient selection is paramount to achieving good surgical results. Identifying predictors of outcomes may aid surgical decision-making and facilitate counseling of patients to manage expectations. METHODS: Prospectively collected registry data of 104 patients who underwent single-level ACDF for cervical spondylotic myelopathy were reviewed. Outcomes assessed at 2 years were the presence of residual neck pain/arm pain (AP), and attainment of a minimal clinically important difference (MCID) for Neck Disability Index (NDI), Japanese Orthopaedic Association (JOA) score, and Physical Component Score (PCS) of SF-36, as well as patient satisfaction, fulfilment of expectations, willingness to undergo same surgery again, return to work (RTW), and return to function (RTF). Receiver operating characteristic curves and multivariate stepwise logistical regression were performed to identify independent predictors of each outcome using 22 covariates including demographics, comorbidities, and preoperative disease state. RESULTS: Lower preoperative NDI was predictive of the absence of residual neck pain/AP at 2 years. Higher preoperative JOA score was predictive of MCID attainment for PCS, satisfaction, expectation fulfilment, willingness to undergo the same surgery for same condition, and RTF. Poorer preoperative scores of NDI, JOA, and PCS were predictors of attaining MCID of the respective scores. Older patients were less likely to attain MCID for JOA. Higher preoperative AP was a risk factor for unsuccessful RTW. CONCLUSIONS: In general, the preoperative JOA score was the best predictor of outcomes after ACDF. A preoperative JOA cutoff value of 9.25-10.25 predicted satisfaction, expectation fulfilment, willingness to undergo same surgery, and RTF with at least 70% sensitivity and 50% specificity. These findings may aid surgeons in identifying patients at risk of a poor outcome and guide preoperative counseling to establish realistic expectations of the surgical outcome. LEVEL OF EVIDENCE: Level III-Non-randomized controlled cohort/follow-up study.

Elderly Patients Undergoing Minimally Invasive Transforaminal Lumbar Interbody Fusion May Have Similar Clinical Outcomes, Perioperative Complications, and Fusion Rates As Their Younger Counterparts.

BACKGROUND: Although several studies have suggested that minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) may be especially beneficial in the elderly population due to lower operative morbidity and faster postoperative recovery, there are limited studies investigating the functional outcomes, quality of life, and satisfaction in elderly patients after MIS-TLIF. Furthermore, existing studies had substantial clinical, diagnostic, and surgical heterogeneity. QUESTIONS/PURPOSES: We asked if elderly patients could experience comparable (1) patient-reported pain, disability and quality of life, (2) perioperative complications, and (3) radiological fusion rates as their younger counterparts after MIS-TLIF. METHODS: Prospectively collected registry data of patients undergoing primary, single-level, MIS-TLIF for degenerative spondylolisthesis between 2012 and 2014 were reviewed. We included 168 patients, 39 of whom were at least 70 years old. Of the 129 patients younger than 70 years old, propensity-score matching was used to select 39 younger controls with adjustment for sex, BMI, American Society of Anesthesiologists score, and baseline clinical outcomes. Perioperative complications and radiologic data were compared. RESULTS: There was no difference in back pain (mean difference -0.3 [95% confidence interval -1.0 to 0.5]; p = 0.52); leg pain (mean difference -0.1 [95% CI to 0.6-0.5]; p = 0.85); Oswestry Disability Index (mean difference -2.9 [95% CI -8.0 to 2.2]; p = 0.26); and SF-36 physical (mean difference 3.0 [95% CI -0.7 to 6.8]; p = 0.107); and mental component summary (mean difference 1.9 [95% CI -4.5 to 8.2]; p = 0.56); up to 2 years postoperatively; 85% of younger patients and 85% of elderly patients were satisfied (p > 0.99) while 87% and 80%, respectively, had fulfilled expectations (p = 0.36). Four perioperative adverse events occurred in each group. There was also no difference in the rate of fusion (87% in younger patients and 90% in elderly patients; p = 0.135). CONCLUSIONS: When clinical and surgical heterogeneity were minimized, elderly patients undergoing minimally invasive transforaminal lumbar interbody fusion not only had comparable rates of perioperative complications but also experienced similar improvements in pain, function, and quality of life. A high rate of satisfaction was achieved. LEVEL OF EVIDENCE: Level II, prognostic study.

Sagittally Balanced Degenerative Spondylolisthesis Patients With Increased Sacral Slope and Greater Lumbar Lordosis Experience Less Back Pain After Short-Segment Lumbar Fusion Surgery.

STUDY DESIGN: A retrospective review of prospectively collected registry data. OBJECTIVES: (1) Examine functional outcomes of patients with postoperative sacral slope (SS)<30 degrees versus SS≥30 degrees after single-level transforaminal lumbar interbody fusion (TLIF) for degenerative spondylolisthesis (DS); (2) determine the factors associated with SS at the last follow-up. SUMMARY OF BACKGROUND DATA: Few studies have examined the relationship between spinopelvic parameters and functional outcomes in patients with DS undergoing short-segment TLIF. Although SS of 30 degrees has been proposed as the ideal spinopelvic parameter for eliminating residual pain and disability in adult spinal deformity, the ideal value for DS remains unknown. METHODS: Prospectively collected registry data of 63 patients who underwent single-level L4-L5 open TLIF with sagittal realignment for DS were reviewed. Pelvic incidence, lumbar lordosis (LL), pelvic tilt, SS, listhesis excursion, and Bridwell fusion grading were recorded. Patients were stratified into SS<30 degrees (n=26) or SS≥30 degrees (n=37) at the last follow-up. All patients were assessed preoperatively and postoperatively at 2 years. Receiver operating characteristics curve analysis was used to assess the relationship between expectation fulfillment and change in SS. RESULTS: Patients with SS≥30 degrees had significantly lower back pain at 2 years (P<0.04). There were no differences in leg pain or outcome scores (Oswestry Disability Index, Short-Form 36 Physical, and Mental Component Summaries), although there was a trend towards better outcomes and higher satisfaction/expectation fulfillment in patients with SS≥30 degrees. The SS≥30 degrees group had a higher preoperative LL (P=0.04) and SS (P<0.01). Preoperative SS was correlated with SS (R=0.71, P<0.01) and LL (R=0.51, P<0.01) at the last follow-up. The area under the curve for change in SS was 0.680 (95% confidence interval, 0.453-0.907) for predicting expectation fulfillment at 2 years. CONCLUSIONS: Patients with increased SS (≥30 degrees) experienced less back pain after short-segment lumbar fusion surgery. This was associated with increased LL postoperatively, indicating better sagittal balance.

Severity of Preoperative Myelopathy Symptoms Affects Patient-reported Outcomes, Satisfaction, and Return to Work After Anterior Cervical Discectomy and Fusion for Degenerative Cervical Myelopathy.

STUDY DESIGN: Retrospective review of prospectively-collected registry data. OBJECTIVE: To compare the patient-reported outcomes, satisfaction, and return to work among a large cohort of patients stratified by preoperative myelopathy severity undergoing Anterior Cervical Discectomy and Fusion (ACDF) for Degenerative Cervical Myelopathy. SUMMARY OF BACKGROUND DATA: Recent clinical practice guidelines noted a lack of studies stratifying their sample based on preoperative disease severity. The benefits of early surgical intervention for patients with mild myelopathy remain uncertain. METHODS: A prospectively-maintained registry was retrospectively reviewed for all patients who underwent primary ACDF for Degenerative Cervical Myelopathy. Patients were stratified based on severity of preoperative myelopathy symptoms according to the Japanese Orthopaedic Association (JOA) scale: mild (>13), moderate (9-13), or severe (<9). Patients were prospectively followed for at least 2 years. RESULTS: In total, 219 patients were included: 74 mild, 94 moderate, and 51 severe cases. The mild group had significantly better Neurogenic Symptoms (NS), Neck Disability Index (NDI), SF-36 Physical (PCS), and Mental Component Summary at baseline (P < 0.05). Neck and arm pain scores were similar at all time points. At 2 years, the severe group still had significantly worse patient-reported outcomes and lower rates of satisfaction, expectation fulfilment and return to work. However, they had significantly greater improvement in JOA, Neurogenic Symptoms, NDI, PCS, and Mental Component Summary, and a larger proportion attained minimal clinically important difference (MCID) for NDI and PCS. All three groups had similar proportions attaining MCID for JOA. CONCLUSION: Patients with severe myelopathy experienced a greater improvement after ACDF. Although fewer patients attained MCID, early surgical intervention for patients with mild myelopathy should also be considered, as this may allow patients to maintain their higher functional status. They also had high rates of postoperative satisfaction and return to work. The clinical trajectory outlined in this study may provide valuable prognostic information for patients. LEVEL OF EVIDENCE: 3.

Patients With Poor Baseline Mental Health May Experience Significant Improvements in Pain and Disability After Minimally Invasive Transforaminal Lumbar Interbody Fusion: A 5-Year Follow-up Study.

STUDY DESIGN: A retrospective study using prospectively collected registry data. OBJECTIVE: Examine the influence of preoperative mental health on outcomes after Minimally Invasive Transforaminal Lumbar Interbody Fusion (MIS-TLIF). SUMMARY OF BACKGROUND DATA: Prior studies investigating the relationship between mental health and outcomes after lumbar spine surgery included small cohorts with short follow-up and heterogenous fusion techniques. The effect of MIS-TLIF on mental health also remains unclear. METHODS: Prospectively collected registry data of 226 patients who underwent single-level MIS-TLIF at a single institution were reviewed. Patients had completed 5-year follow-up data and were assigned into propensity score-matched groups: poor baseline mental health, that is, low Mental Component Summary (MCS) (<50, n=113) and normal baseline mental health, that is, high MCS (≥50, n=113). Outcomes assessed were visual analog scale for back pain (BP), leg pain (LP), Oswestry Disability Index (ODI), Short-Form 36, North American Spine Society-Neurogenic Symptoms (NS), return to work, return to function, satisfaction, and expectation fulfillment. Length of operation and length of stay were recorded. RESULTS: Preoperative MCS was 40.6±8.2 and 58.5±5.4 in the low and high MCS groups, respectively, after propensity score matching (P<0.001). At 5 years, the high MCS group had significantly lower LP (P=0.020) and NS (P=0.009). Despite a significantly poorer baseline (44.3 vs. 38.7, P=0.007) and 6-month ODI (20.3 vs. 15.7, P=0.018) in the low MCS group, both groups achieved a comparable ODI at 5 years (P=0.084). There was no significant difference in proportion that achieved minimal clinically important difference for ODI, PCS, BP, and LP (P>0.05). Both groups reported similar proportions that return to work. However, the low MCS group had a smaller proportion of patients that return to function at 5 years (P=0.025). CONCLUSIONS: Although patients with poorer baseline mental health had greater pain and worse NS preoperatively and up to 5 years postoperatively, a similar proportion experienced a clinically significant improvement in all outcomes. LEVEL OF EVIDENCE: Level III-nonrandomized cohort study.

Perioperative Factors Influencing Postoperative Satisfaction After Lateral Access Surgery for Degenerative Lumbar Spondylolisthesis.

BACKGROUND: Lateral access surgery (LAS) for lumbar degenerative spondylolisthesis is a minimally invasive lumbar fusion technique which has been gaining increasing popularity in the recent years. This study aims to identify perioperative factors that influence postoperative satisfaction after LAS for lumbar degenerative spondylolisthesis. METHODS: From August 2010 to November 2014, 52 patients with lumbar degenerative conditions (16 male: 36 female, mean age 64.0 ± 8.7 years) were prospectively recruited and underwent LAS by a single surgeon. All patients were assessed preoperatively and 2 years postoperatively with Numerical Pain Rating Scale (NPRS), Oswestry Disability Index, Short-Form 36 (SF-36) scores, North American Spine Society score for neurogenic symptoms, patient satisfaction, and expectation fulfillment. Cobb angles, global lumbar lordosis, disc heights, adjacent disc heights, fusion, and subsidence were rates assessed. Multiple linear regression performed with satisfaction as dependent variable to identify predictive independent variables. RESULTS: Lower preoperative SF-36 general health scores (P = .03), higher NPRS leg pain scores (P = .04), and longer surgical duration (P = .02) were significant predictors of lower satisfaction (P < .05). NPRS back and leg pain decreased by 80.3 and 83.0%, respectively. Oswestry Disability Index and North American Spine Society score for neurogenic symptoms improved by 76.2 and 75.9%, respectively. Ninety percent of patients reported excellent/good satisfaction. Significant correction and maintenance of Cobb and global lumbar lordosis angles were achieved. There was significant increase in disc heights postoperatively (P = .05) and no significant difference in adjacent disc heights at 2 years (P > .05). Ninety-eight percent of patients achieved Bridwell Fusion Grade 1, and 5.8% had Marchi Grade 3 subsidence. CONCLUSIONS: Lower preoperative SF-36 general health, higher NPRS leg pain, and longer surgical duration are predictors of lower satisfaction in patients undergoing LAS for lumbar degenerative spondylolisthesis. LEVEL OF EVIDENCE: III. CLINICAL RELEVANCE: Identifying preoperative predictors for postoperative clinical outcome can assist clinicians in patient education prior to operation.

Reduction in foraminal height after lateral access surgery does not affect quality of life: A 2-year outcome study on lateral lumbar interbody fusion.

INTRODUCTION: Reduction in neuroforaminal height (FH) may diminish the indirect decompression benefit that lateral access surgery (LAS) provides. However, the relationship between postoperative FH reduction in LAS and health-related quality-of-life (HRQoL) outcomes remains unclear. OBJECTIVES: To determine whether FH reduction affects HRQoL outcomes at 2-year follow-up. METHODS: A retrospective review of 45 patients who underwent LAS for degenerative lumbar spine conditions was performed. The cohort was divided into two groups: maintenance (A) and reduction (B) in FH. Outcome measures included numerical pain rating scale (NPRS back and leg pain), Oswestry Disability Index (ODI), Short Form 36 Health Survey (SF-36), North American Spine Society (NASS) score for neurogenic symptoms (NS), patient satisfaction, and expectation fulfilment for surgery. Mean disc height (DH), FH, and fusion were evaluated on plain radiographs. Radiological fusion was assessed with the Bridwell fusion classification. Unpaired student's t-test was used to compare between groups and one-way ANOVA with Bonferroni post hoc correction was used to determine differences between time intervals within each group. RESULTS: The average pre-op mean FH was 16.9 ± 3.5 mm. Group A had 25 patients showing postoperative maintenance of FH (19.4 ± 3.3 mm to 20.2 ± 3.2 mm; 4% increase) at 2-year postsurgery while group B had 20 patients showing decrease in FH (21.1 ± 3.3 mm to 18.7 ± 3.5 mm; 11% decrease). Group A mean DH improved from 7.0 ± 2.0 mm to 10.3 ± 1.6 mm (47% increase). Group B mean DH improved from 6.8 ± 2.3 mm to 11.0 ± 3.0 mm (62% increase). There were no significant differences in NPRS, ODI, NASS, SF-36, and SF-36 MCS/PCS between groups at 2 years ( p > 0.05); 92% of group A and 85% of group B patients reported good satisfaction and fulfilment of expectations ( p > 0.05). CONCLUSION: Despite an initial increase in FH after LAS surgery, 45% of patients had FH reduction at 2 years. However, FH reduction up to 11% did not affect short-term HRQoL outcomes.

The Influence of Body Mass Index on Functional Outcomes, Satisfaction, and Return to Work After Single-level Minimally-invasive Transforaminal Lumbar Interbody Fusion: A Five-year Follow-up Study.

STUDY DESIGN: Retrospective study using prospectively collected registry data. OBJECTIVES: To evaluate the effect of obesity on patient-reported outcome measures of pain, disability, quality of life, satisfaction, and return to work after single-level minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF). SUMMARY OF BACKGROUND DATA: MIS-TLIF is an appealing alternative for obese patients with potentially lower complication risk. However, there is limited data investigating the influence of obesity on outcomes 5 years after MIS-TLIF. METHODS: Prospectively collected registry data of 296 patients who underwent single-level MIS-TLIF at a single institution were reviewed. Patients had complete 2- and 5-year follow-up data. Patients were stratified into control (<25.0 kg/m), overweight (25.0-29.9 kg/m), and obese (≥30.0 kg/m) groups. Outcomes assessed were visual analogue scale for back pain, leg pain, Oswestry Disability Index, Short-form 36, North American Spine Society score for neurogenic symptoms, return to work (RTW), return to function (RTF), satisfaction, and expectation fulfilment. Length of operation, length of stay, and comorbidities were recorded. RESULTS: Among the patients, 156 (52.7%) had normal weight, 108 (36.5%) were overweight, and 32 (10.8%) were obese. There was no difference in length of operation or hospitalization (P > 0.05). All three groups had comparable preoperative scores at baseline (P > 0.05). At 5 years, the control group had significantly higher PCS compared with the overweight (P = 0.043) and obese groups (P = 0.007), although the change in scores was similar (P > 0.05). The rate of MCID attainment, RTW, RTF, expectation fulfilment, and satisfaction was comparable. CONCLUSION: Nonobese patients had better physical well-being in the mid-term, although obese patients experienced a comparable improvement in clinical scores. Obesity had no impact on patients' ability to RTW or RTF. Equivalent proportions of patients were satisfied and had their expectations fulfilled up to 5 years after MIS-TLIF. LEVEL OF EVIDENCE: 3.

Time Taken to Return to Work Does Not Influence Outcomes of Minimally Invasive Transforaminal Lumbar Interbody Fusion: A 5-Year Follow-Up Study.

STUDY DESIGN: Retrospective cohort study using prospectively collected registry data. OBJECTIVE: To determine factors which influence return-to-work (RTW) in patients undergoing minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) and to determine if early RTW affects functional outcomes. SUMMARY OF BACKGROUND DATA: MIS-TLIF has been associated with accelerated return to work. RTW in non-WC working-age adults after MIS-TLIF is not well understood. METHODS: Prospectively collected registry data of 907 patients who underwent MIS-TLIF at a single institution from 2004 to 2013 were reviewed. One hundred ten working adults who underwent single-level MIS-TLIF with complete preoperative and 5-year postoperative follow-up data were included. Patients were assigned into Early RTW (≤60 d, n = 40) and Late RTW (>60 d, n = 70). All patients were assessed pre- and postoperatively at 2 and 5 years. Length of operation, length of stay, and comorbidities were also recorded. RESULTS: The Early RTW group had significantly lower Oswestry Disability Index (ODI), North American Spine Society score for neurogenic symptoms (NASS NS), numerical pain rating scale (NPRS) back and leg pain scores than the Late RTW group (<0.01) There were no significant differences in age, body mass index (BMI) and prevalence of medical comorbidities (P > 0.05). In addition, there were no differences in terms of duration of surgery or length of hospitalization. There were no significant differences in ODI, NASS NS, Short-form 36 physical and mental component scores (SF-36 PCS/MCS), NPRS, satisfaction/expectation fulfilment between the Early and Late RTW groups at 2-year and 5-year follow-up. Both groups reported similar proportions that RTW without limitations and return-to-function (RTF) at 2-years and 5-years. CONCLUSION: Patients who RTW late have significantly poorer preoperative SF-36 physical component scores and higher ODI, NASS NS, NPRS back/leg pain scores. Surgeons should be cognizant that working adults with poorer preoperative function will tend to return to work later, but should reassure them that they will likely achieve similar clinical outcomes, satisfaction and expectation fulfilment when compared with patients who returned to work early. LEVEL OF EVIDENCE: 3.

Poor Baseline Mental Health Does Not Influence Improvement in Patient-reported Outcomes, Satisfaction, and Return to Work Two Years After Single-level Anterior Cervical Discectomy and Fusion.

STUDY DESIGN: Retrospective study using prospectively collected registry data. OBJECTIVE: The authors examine the influence of preoperative mental health on outcomes after anterior cervical discectomy and fusion (ACDF) and determine the impact of ACDF on postoperative mental health. SUMMARY OF BACKGROUND DATA: While studies have reported a negative correlation between preoperative mental health and outcomes following lumbar spine surgery, the influence on outcomes following cervical spine surgery remains relatively understudied. METHODS: Prospectively collected registry data of 104 patients who underwent single-level ACDF for cervical spondylotic myelopathy were reviewed. Patients were dichotomized into top and bottom halves based on preoperative SF-36 MCS (Mental Component Summary) using a cutoff of 48. Outcomes assessed were visual analogue scale for neck pain, arm pain, AAOS Neck Pain and Disability, Neurogenic Symptoms, Neck Disability Index, Short-Form 36, Japanese Orthopaedic Association myelopathy score, return to work, return to function, satisfaction and expectation fulfilment up to 2 years postoperatively. RESULTS: The preoperative MCS was 37.5 ±â€Š8.1 and 57.4 ±â€Š6.3 in the Low and High MCS groups respectively (P < 0.001). The Low MCS group had poorer preoperative scores (P < 0.05). There was no significant difference in length of stay or comorbidities (P > 0.05). The High MCS group had less neck pain (P = 0.002) and showed a trend towards lower Neck Disability Index (P = 0.062) at 2 years. The Low MCS group demonstrated greater improvement in Japanese Orthopaedic Association (P = 0.007) and similar improvement in other scores (P > 0.05). There was no significant difference in proportion that achieved minimal clinically important difference for each score (P > 0.05). Both groups had similar rates of return to work, return to function, expectation fulfilment, and satisfaction (P > 0.05). Lower preoperative MCS was predictive of greater improvement in MCS (r = -0.477, P < 0.001). CONCLUSION: Despite relatively greater pain and disability at 2 years, patients with poor baseline mental health experienced similar improvement in clinical outcomes, return to work, and satisfaction rates. LEVEL OF EVIDENCE: 3.

Low Infection Rates in Total Knee Arthroplasty in End Stage Renal Failure Patients.

End stage renal failure is considered a risk factor for postoperative infection and many surgeons are cautious in offering this group of patients total knee arthroplasty for symptomatic osteoarthritis. In this retrospective study, 16 total knee arthroplasties were performed in 13 patients and each case was followed up for an average of 5.1 years. We report no cases of infection and also an overall improvement in multiple validated outcome measures. There were, however, 2 cases of periprosthetic loosening. As the patients in our series were generally younger and none was diagnosed with stroke or peripheral vascular disease at the time of surgery, we believe that careful patient selection is key to reducing infection rates in this challenging group of patients.