To Örebro University

BACKGROUND: Enhanced Recovery After Surgery (ERAS) evidence-based protocols for perioperative care have led to improvements in outcomes in numerous surgical areas, through multimodal optimization of patient pathway, reduction of complications, improved patient experience and reduction in the length of stay. ERAS represent a relatively new paradigm in spine surgery.

PURPOSE: This multidisciplinary consensus review summarizes the literature and proposes recommendations for the perioperative care of patients undergoing lumbar fusion surgery with an ERAS program.

STUDY DESIGN: This is a review article.

METHODS: Under the impetus of the ERAS (R) society, a multidisciplinary guideline development group was constituted by bringing together international experts involved in the practice of ERAS and spine surgery. This group identified 22 ERAS items for lumbar fusion. A systematic search in the English language was performed in MEDLINE, Embase, and Cochrane Central Register of Controlled Trials. Systematic reviews, randomized controlled trials, and cohort studies were included, and the evidence was graded according to the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) system. Consensus recommendation was reached by the group after a critical appraisal of the literature.

RESULTS: Two hundred fifty-six articles were included to develop the consensus statements for 22 ERAS items; one ERAS item (prehabilitation) was excluded from the final summary due to very poor quality and conflicting evidence in lumbar spinal fusion. From these remaining 21 ERAS items, 28 recommendations were included. All recommendations on ERAS protocol items are based on the best available evidence. These included nine preoperative, eleven intraoperative, and six postoperative recommendations. They span topics from preoperative patient education and nutritional evaluation, intraoperative anesthetic and surgical techniques, and postoperative multi-modal analgesic strategies. The level of evidence for the use of each recommendation is presented.

CONCLUSION: Based on the best evidence available for each ERAS item within the multidisciplinary perioperative care pathways, the ERAS (R) Society presents this comprehensive consensus review for perioperative care in lumbar fusion.

Study Design: Systematic Review.

Objective: To collect and group definitions of segmental instability, reported in surgical studies of patients with lumbar spinal stenosis (LSS) and/or lumbar degenerative spondylolisthesis (LDS). To report the frequencies of these definitions. To report on imaging measurement thresholds for instability in patients and compare these to those reported in biomechanical studies and studies of spine healthy individuals.To report on studies that include a reliability study.

Methods: This review was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. Studies eligible for inclusion were clinical and biomechanical studies on adult patients with LDS and/or LSS who underwent surgical treatment and had data on diagnostic imaging. A systematic literature search was conducted in relevant literature databases. Full text screening inclusion criteria was definition of segmental instability or any synonym. Two reviewers independently screened articles in a two-step process. Data synthesis presented by tabulate form and narrative synthesis.

Results: We included 118 studies for data extraction, 69% were surgical studies with decompression or fusion as interventions, 31% non-interventional studies. Grouping the definitions of segmental instability according similarities showed that 24% defined instability by dynamic sagittal translation, 26% dynamic translation and dynamic angulation, 8% used a narrative definition. Comparison showed that non-interventional studies with a healthy population more often had a narrative definition.

Conclusion: Despite a reputation of non-consensus, segmental instability in the degenerative lumbar spine can radiologically be defined as > 3 mm dynamic sagittal translation.

Study design: Retrospective cohort study.

Objective: The aim was to investigate whether findings on magnetic resonance imaging (MRI) can be proxies (MRIPs) for segmental instability in patients with degenerative lumbar spinal stenosis (LSS) and/or degenerative spondylolisthesis (LDS) L4/L5.

Background: LDS has a heterogeneous nature. Some patients have a dynamic component of segmental instability associated with LDS. Studies have shown that MRI can show signs of instability.

Methods: Patients with LSS or LDS at L4/L5 undergoing decompressive surgery +/- fusion from 2010 to 2017, with preoperative standing lateral spine radiographs and supine lumbar MRI and enrolled in Danish national spine surgical database, DaneSpine. Instability defined as slip of >3 mm on radiographs. Patients divided into two groups based upon presence of instability. Outcome measures: radiograph: sagittal slip (mm). MRIPs for instability: sagittal slip >3 mm, facet joint angle (degrees), facet joint effusion (mm), disk height index (%), and presence of vacuum phenomena. Optimal thresholds for MRIPs was determined by receiver operating characteristic (ROC) curves and area under the curve (AUC). Logistic regression to investigate association between instability and MRIPs.

Results: Two hundred thirty-two patients: 47 stable group and 185 unstable group. The two groups were comparable with regard to baseline patient-reported outcome measures. Thresholds for MRIPs: bilateral facet joint angle >= 46 degrees; bilateral facet effusion >= 1.5 mm and disk height index >= 13%. Logistic regression showed statistically significant association with MRIPs except vacuum phenomena, ROC curve AUC of 0.951. By absence of slip on MRI logistic regression showed statistically significant association between instability on radiograph and the remaining MRIPs, ROC curve AUC 0.757.

Conclusion: Presence of MRIPs for instability showed statistically significant association with instability and excellent ability to predict instability on standing radiograph in LSS and LDS patients. Even in the absence of slip on MRI the MRIPs had a good ability to discriminate presence of instability.

Background and purpose: Indication for lumbar disc herniation (LDH) surgery is usually to relieve sciatica. We evaluated whether back pain also decreases after LDH surgery.

Patients and methods: In the Swedish register for spinal surgery (SweSpine) we identified 14,097 patients aged 20-64 years, with pre- and postoperative data, who in 2000-2016 had LDH surgery. We calculated 1-year improvement on numeric rating scale (rating 0-10) in back pain (N_back) and leg pain (N_leg) and by negative binomial regression relative risk (RR) for gaining improvement exceeding minimum clinically important difference (MCID).

Results: N_leg was preoperatively (mean [SD]) 6.7 (2.5) and N_back was 4.7 (2.9) (p < 0.001). Surgery reduced N_leg by mean 4.5 (95% CI 4.5-4.6) and N_back by 2.2 (CI 2.1-2.2). Mean reduction in N_leg) was 67% and in N_back 47% (p < 0.001). Among patients with preoperative pain ≥ MCID (that is, patients with significant baseline pain and with a theoretical possibility to improve above MCID), the proportion who reached improvement ≥ MCID was 79% in N_leg and 60% in N_back. RR for gaining improvement ≥ MCID in smokers compared with non-smokers was for N_leg 0.9 (CI 0.8-0.9) and -N_back 0.9 (CI 0.8-0.9), and in patients with preoperative duration of back pain 0-3 months compared with > 24 months for N_leg 1.3 (CI 1.2-1.5) and for N_back 1.4 (CI 1.2-1.5).

Interpretation: LDH surgery improves leg pain more than back pain; nevertheless, 60% of the patients with significant back pain improved ≥ MCID. Smoking and long duration of pain is associated with inferior recovery in both N_leg and N_back.

Background: A 25-year-old patient was treated for post-traumatic neck pain with intradiscal injections at the C3-4 and C4-5 levels using radiopaque gelified ethanol. After the injections, the axial neck pain increased. Laboratory infection parameters were normal despite the progressive disc destruction observed on CT scans at both index levels. The patient underwent debridement and anterior cervical discectomy and fusion. Staphylococcus epi-dermidis and Cutibacterium acnes grew in all the intraoperative cultures. The patient was subsequently treated with Rifampicin and Moxifloxacin and after 3 months no signs of infection were observed. CT scan showed solid fusion of the at the index segments 7 months postoperatively.

Conclusion: Infections after intradiscal injections are rare and we believe this is the first case describing iatrogenic spondylodiscitis after DiscoGel injection. When increased axial neck pain is experienced after injection with DiscoGel, post-operative spondylodiscitis should be suspected. Even if laboratory parameters are normal, examinations with MRI and CT should be performed and if these studies show signs of infection, surgical revision should be conducted.

BACKGROUND: Cervical radiculopathy is the most common disease in the cervical spine, affecting patients around 50-55 year of age. An operative treatment is common clinical praxis when non-operative treatment fails. The controversy is in the choice of operative treatment, conducting either anterior cervical decompression and fusion or posterior foraminotomy. The study objective is to evaluate short- and long-term outcome of anterior cervical decompression and fusion (ACDF) and posterior foraminotomy (PF)

METHODS: A multicenter prospective randomized controlled trial with 1:1 randomization, ACDF vs. PF including 110 patients. The primary aim is to evaluate if PF is non-inferior to ACDF using a non-inferiority design with ACDF as "active control." The neck disability index (NDI) is the primary outcome measure, and duration of follow-up is 2 years.

DISCUSSION: Due to absence of high level of evidence, the authors believe that a RCT will improve the evidence for using the different surgical treatments for cervical radiculopathy and strengthen current surgical treatment recommendation.

TRIAL REGISTRATION: ClinicalTrials.gov NCT04177849. Registered on November 26, 2019.

STUDY DESIGN: Register study with prospectively collected data.

OBJECTIVE: The aim was to investigate reoperation rates at the index level and the adjacent levels after surgery for lumbar L3-4 spinal stenosis with concomitant degenerative spondylolisthesis (DS).

SUMMARY OF BACKGROUND DATA: There are different opinions on how to surgically address lumbar spinal stenosis with DS. The potential benefit of fusion surgery should be weighed against the risks of future reoperations because of adjacent segment degeneration. Data on the reoperation rate at adjacent segments after single level L3-4 fusion surgery are limited.

MATERIALS AND METHODS: A total of 372 patients, who underwent surgery for lumbar L3-4 spinal stenosis with DS (slip >3 mm) between 2007 and 2012, were followed between 2007 and 2017 to identify reoperations at the index level and adjacent levels. The reoperation rate for decompression and fusion was compared with the reoperation rate for decompression only. Patient-reported outcome measures before and 1 year after surgery were evaluated.

RESULTS: The reoperation rate at the index level (L3-4) was 3.5% for decompression and fusion and 5.6% for decompression only. At the cranial adjacent level (L2-3), the corresponding numbers were 6.6% and 4.2%, respectively, and the caudal adjacent level (L4-5), the corresponding numbers were 3.1% and 4.9%, respectively. The effect sizes of change were larger for decompression and fusion compared with decompression only. The effect sizes of change were similar for leg pain and back pain.

CONCLUSIONS: We could not identify any differences in reoperation rates at the cranial or caudal adjacent segment after decompression and fusion compared with decompression only for L3-4 spinal stenosis with DS. The improvement in back pain is similar to the improvement in leg pain after surgery for L3-4 spinal stenosis with DS.

Background and purpose: There are different opinions on how to surgically address lumbar spinal stenosis with concomitant degenerative spondylolisthesis (DS). We investigated reoperation rates at the index and adjacent levels after L4-5 fusion surgery in a large cohort of unselected patients registered in Swespine, the national Swedish spine register.

Patients and methods: 6,532 patients, who underwent surgery for L4-5 spinal stenosis with or without DS between 2007 and 2012, were followed up to 2017 to identify reoperations at the index and adjacent levels. The reoperation rates for decompression and fusion were compared with the reoperation rates for decompression only and for patients with or without DS. Patient-reported outcome data were collected preoperatively, and at 1 and 2 years after surgery and used to evaluate differences in outcome between index operations and reoperations.

Results: For spinal stenosis with DS, the reoperation rate at the index level was 3.0% for decompression and fusion and 6.0% for decompression only. At the adjacent level, the corresponding numbers were 9.7% and 4.2% respectively. For spinal stenosis without DS, the reoperation rate at the index level was 3.7% for decompression and fusion and 6.2% after decompression only. At the adjacent level, the corresponding numbers were 8.1% and 3.8% respectively. For the reoperations at the adjacent level, there was no difference in patient-reported outcome between extended fusion or decompression only.

Interpretation: Single-level lumbar fusion surgery is associated with an increased rate of reoperations at the adjacent level compared with decompression only. When reoperations at the index level are included there is no difference in reoperation rates between fusion and decompression only.

Purpose: The EQ VAS is an integral part of EQ-5D, a commonly used instrument for health-related quality of life assessment. This study aimed to calculate the minimal important change (MIC) thresholds for the EQ VAS for improvement and deterioration after surgery for disk herniation or spinal stenosis.

Methods: Patients, who were surgically treated for disk herniation or spinal stenosis between 2007 and 2016, were recruited from the Swedish spine register. Preoperative and 1-year postoperative data for a total of 25772 procedures were available for analysis. We used two anchor-based methods to estimate MIC for EQ VAS: (1) a predictive model based on logistic regression and (2) receiver operating characteristics (ROC) curves. The SF-36 health transition item was used as anchor.

Results: The EQ VAS MIC threshold for improvement after disk herniation surgery ranged from 8.25 to 11.8 while the corresponding value for deterioration ranged from - 6.17 to 0.5. For spinal stenosis surgery the corresponding MIC values ranged from 10.5 to 14.5 and - 7.16 to - 6.5 respectively. There were moderate negative correlations (disk herniation - 0.47, spinal stenosis - 0.46) between the 1 year change in the EQ VAS and the SF-36 health transition item (MIC anchor).

Conclusions: For EQ VAS, we recommend a MIC threshold of 12 points for improvement after surgery for disk herniation or spinal stenosis, whereas the corresponding threshold for deterioration is - 7 points. There are marked differences between the EQ VAS MIC for improvement and deterioration after surgery for disk herniation or spinal stenosis. The MIC value varied depending on the method used for MIC estimation.

Objectives: To identify rates of additional operation after the index operation for degenerative lumbar spine diseases.Design Retrospective register study.Setting National outcome data from Swespine, the National Swedish spine register.

Participants: A total of 4705 patients who underwent one-level surgery for degenerative disk disease (DDD) or lumbar spinal stenosis (LSS) with or without degenerative spondylolisthesis (DS) between 1 January 2007 and 31 December 2010 were followed from 1 January 2007 to 31 December 2020 to record all cases of additional lumbar spine operations.Interventions One-level spinal decompression and/or posterolateral fusion for degenerative spine diseases.

Primary outcome measures: Number of additional operations.

Results: Additional operations were more common at adjacent levels for patients with LSS with DS treated with decompression and fusion whereas additional operations were more evenly distributed between the index level and the adjacent levels for DDD treated with fusion and LSS with and without DS treated with decompression only. For patients younger than 60 years, treated with decompression and fusion for LSS with DS, the additional operations were evenly distributed between the index level and the adjacent levels.

Conclusions: There are different patterns of additional operations following the index procedure after surgery for degenerative spine diseases. Rigidity across previously mobile segments is not the only important factor in the development of adjacent segment disease (ASD) after spinal fusion, also the underlying disease and age may play parts in ASD development. The findings of this study can be used in the shared decision-making process when surgery is a treatment option for patients with degenerative lumbar spine diseases as the first operation may be the start of a series of additional spinal operations for other degenerative spinal conditions, either at the index level or at other spinal levels.

Background and purpose: There are several national value sets for SF-6D. For studies conducted in countries without a country-specific value set the authors may use a value set from a neighboring or culturally similar county. We evaluated the consequences of using different national value sets in SF-6D index-based outcome analyses.

Patients and methods: Patients surgically treated for lumbar spinal stenosis or lumbar disk herniation between 2007 and 2017 were recruited from the national Swedish spine register. 16,398 procedures were eligible for analysis. The SF-6D health states were coded to SF-6D preference indices using value sets for 9 countries. The SF-6D index distributions were then estimated with kernel density estimation. The change in SF-6D index before and after treatment was evaluated with the standardized response mean (SRM).

Results: There was a marked variability in mean and shape for the resulting SF-6D index distributions. There were considerable differences in SF-6D index distribution shape before and after treatment using the same value set. The effect sizes of 2-year change (SRM) were in most cases similar when the 9 value sets were applied on pre- and post-treatment data.

Interpretation: We found a marked variability in SF-6D index distributions when a single large data set was applied to 9 national SF-6D value sets. Consequently, we recommend that SF-6D index data from studies conducted in countries without country-specific SF-6D value sets is interpreted with caution.

PURPOSE: The purpose of the current study was to apply a single large longitudinal EQ-5D-3L data set to several national EQ-5D-3L value sets and explore differences in EQ-5D-3L index density functions and effect sizes before and after treatment.

METHODS: Patients, surgically treated for lumbar spinal stenosis or lumbar disk herniation between 2007 and 2017, were recruited from the national Swedish spine register. A total of 27,328 procedures were eligible for analysis. The EQ-5D health states were coded to EQ-5D-3L summary indices using value sets for 9 countries: Argentina, Australia, Canada, China, Germany, Italy, Sweden, the UK, and the US. The EQ-5D-3L summary index distributions were then estimated with kernel density estimation. The change in EQ-5D-3L index before and after treatment was evaluated with the standardized response mean (SRM).

RESULTS: There was a high variability in the resulting EQ-5D-3L index density functions. There were also considerable differences in EQ-5D-3L index density functions before and after treatment using the same value set. Effect sizes of 2-year change (SRM), however, were similar when the 9 value sets were applied on pre- and post-treatment data.

CONCLUSIONS: We found a marked variability in EQ-5D-3L index density functions when a single large data set was applied to 9 national EQ-5D-3L value sets. Consequently, studies that aggregate international data, e.g. meta-analyses, may produce misleading results if the underlying differences in EQ-5D-3L index density functions are inadequately handled. On the basis of the results of our study, we recommend against pooling of different national EQ-5D-3L index data.

PURPOSE: The study evaluated perceptions of general health (GH) after surgical treatment of spinal stenosis and disk herniation. We used a large longitudinally collected data set to explore differences in responsiveness between the SF-36 GH domain, EQ VAS, EQ-5D index, and SF-6D index.

METHODS: Patients, surgically treated for lumbar spinal stenosis or lumbar disk herniation between 2007 and 2017, were recruited from the national Swedish spine register. A total of 14,883 procedures were eligible for analysis. The responsiveness of the SF-36 GH domain to surgical treatment was evaluated with the standardized response mean (SRM) and effect size (ES). The internal consistency of the GH domain was evaluated, ceiling and floor effects were assessed, and the correlation between GH domain and EQ VAS was analyzed.

RESULTS: The SF-36 GH domain did not respond to surgical treatment of spinal stenosis and disk herniation. In contrast, EQ VAS, EQ-5D index, and SF-6D showed moderate to large responsiveness. There were pronounced ceiling effects in items 11a-c of the SF-36 GH domain. There was a negative effect size of change for item 11c. The internal consistency of the GH domain was satisfactory. There were marked differences in the correlations between EQ VAS and the GH domain preoperatively and postoperatively.

CONCLUSIONS: The SF-36 GH domain should be used with caution when evaluating effects on GH perceptions after spine surgery procedures. The lack of responsiveness is most probably explained by ceiling effects for items 11a-c and a negative effect size of change for item 11c.

Background: Previous studies have shown that patients with different lumbar spine diseases report different SF-36 profiles, but data on the stability of the SF-36 profiles are limited. The primary aim of the current study was to evaluate the stability of the SF-36 profile for lumbar spine diseases.

Methods: Patients, surgically treated between 2007 and 2016 for three lumbar spine diseases, lumbar spinal stenosis (LSS) with degenerative spondylolisthesis (DS), LSS without DS, and lumbar disk herniations (LDH), were identified in the Swedish spine register. Preoperative and 1 year postoperative SF-36 data for a total of 27,302 procedures were available for analysis. The stability of the SF-36 profiles over the 10-year period was evaluated using graphical exploration, linear regression, difference in means, and 95% confidence intervals. The responsiveness of the SF-36 domains to surgical treatment was evaluated using the standardized response mean (SRM).

Results: LSS and LDH have different SF-36 profiles. LSS with DS and LSS without DS have similar SF-36 profiles. The preoperative and the 1 year postoperative SF-36 profiles were stable from 2007 to 2016 for all three diagnoses. There were no major changes in the effect size of change (SRM) during the study period for all three diagnoses. For LSS with DS, the number of fusions peaked in 2010 and then decreased. The postoperative SF-36 profiles for LSS with DS were unaffected by changes in surgical treatment trends.

Conclusions: Patients with lumbar spinal stenosis and lumbar disk herniations have different SF-36 profiles. Concomitant degenerative spondylolisthesis had no impact on the SF-36 profile of lumbar spinal stenosis. Adding fusion to the decompression did not alter the postoperative SF-36 profile of lumbar spinal stenosis. The SF-36 health profiles are stable from a 10 years perspective.

PURPOSE: In spine surgery single item patient-reported outcome assessment has been used for many years. Items 1 and 2 of SF-36 are used for assessment of general health. We used these items to explore single item, self-rated, general health assessment after spine surgery.

METHODS: Patients operated for lumbar disc herniation or lumbar spinal stenosis between 2007 and 2017, were recruited from the national Swedish spine register. A total of 16,910 procedures were eligible for analysis. The responsiveness of the SF-36 general health assessment items to surgical treatment was evaluated with the standardized response mean (SRM). Improvement in self-rated general health was used to dichotomize SF-36 profiles and EQ VAS distributions.

RESULTS: For disc herniation, 5852 (83%) patients reported improvement in general health 1 year after surgery. For spinal stenosis, the corresponding numbers were 6,482 (66%). The additional improvement after year 1 was small. The responsiveness of the SF-36 item 2 (the health transition item) to surgical treatment of disc herniation or spinal stenosis was substantial. There was a clear association between improvement in SF-36 item 2 and improvements in all domains of SF-36.

CONCLUSIONS: Surgery for disc herniation or spinal stenosis improve patients' perception of general health 1 year after surgery. The improvement in general health after year 1 is limited. The SF-36 item 2 is a responsive measure of self-rated general health that may be used for dichotomization of SF-36 and EQ VAS data when evaluating surgical outcome in spine surgery.

OBJECTIVE: This study aimed to investigate the associations between general health expectations and patient satisfaction with treatment for the two common spine surgery procedures diskectomy for lumbar disk herniation (LDH) and decompression for lumbar spinal stenosis (LSS). DESIGN: Register study with prospectively collected preoperative and 1-year postoperative data.

SETTING: National outcome data from Swespine, the national Swedish spine register.

PARTICIPANTS: A total of 9929 patients, aged between 20 and 85 years, who were self-reported non-smokers, and were operated between 2007 and 2016 for one-level LSS without degenerative spondylolisthesis, or one-level LDH, were identified in the national Swedish spine register (Swespine). We used SF-36 items 11c and 11d to assess future health expectations and present health perceptions. Satisfaction with treatment was assessed using the Swespine satisfaction item.

INTERVENTIONS: One-level diskectomy for LDH or one-level decompression for LSS.

PRIMARY OUTCOME MEASURES: Satisfaction with treatment. RESULTS: For LSS, the year 1 satisfaction ratio among patients with negative future health expectations preoperatively was 60% (95% CI 58% to 63%), while it was 75% (95% CI 73% to 76%) for patients with positive future health expectations preoperatively. The corresponding numbers for LDH were 73% (95% CI 71% to 75%) and 84% (95% CI 83% to 85%), respectively.

CONCLUSIONS: Patients operated for the common lumbar spine diseases LSS or LDH, with negative future general health expectations, were significantly less satisfied with treatment than patients with positive expectations with regard to future general health. These findings are important for patients, and for the surgeons who counsel them, when surgery is a treatment option for LSS or LDH.

Background: The purpose of this study was to evaluate the impact of using different country-specific value sets in EQ-5D-5L based outcome analyses.

Methods: We obtained data on patients surgically treated with total hip arthroplasty (THA) between 2017 and 2019 from the national Swedish Hip Arthroplasty Register. Preoperative and one-year postoperative data on a total of 28,902 procedures were available for analysis. The EQ-5D-5L health states were coded to the EQ-5D-5L preference indices using 13 European value sets. The EQ-5D-5L index distributions were then estimated with kernel density estimation. The change in EQ-5D-5L index before and one year after treatment was evaluated with the standardized response mean (SRM). The lifetime gain in quality-adjusted life years (QALYs) was estimated with a 3.5% annual QALY discount rate.

Findings: There was a marked variability in means and shapes of the resulting EQ-5D-5L index distributions. There were also considerable differences in the EQ-5D-5L index distribution shape before and after the treatment using the same value set. The effect sizes of one-year change (SRM) were similar for all value sets. However, the differences in estimated QALY gains were substantial.

Interpretation: The EQ-5D-5L index distributions varied considerably when a single large data set was applied to different European EQ-5D-5L value sets. The most pronounced differences were between the value sets based on experience-based valuation and the value sets based on hypothetical valuation. This illustrates that experience-based and hypothetical value sets are inherently different and also that QALY gains derived with different value sets are not comparable. Our findings are of importance in study planning since the results and conclusions of a study depend on the choice of value set.

Funding: None.

BACKGROUND: Total hip replacement (THR) is a very successful and refined surgical procedure when compared to crude bony fusion in degenerative lumbar segmental instability (LF). We compared the pre- and postoperative health-related quality of life status of THR and LF patients.

PATIENTS AND METHODS: We prospectively studied 51 THR patients and 50 LF patients. The outcome parameters were SF-36 and Oswestry Disability Index (ODI), measured preoperatively and at 1 year postoperatively. The status of the patients was compared to that of an age-matched healthy control group.

RESULTS: The preoperative SF-36 and ODI scores were similar between the groups, except for the subscale role emotional. One year postoperatively, only the differences in 3 subscales (physical functioning, role physical, and role emotional) and in the standardized physical component reached statistical significance; the THR-patients scored worse than the LF-patients. The improvements in SF-36 and ODI reached statistical significance in both groups.

INTERPRETATION: The differences in quality of life between the THR and LF patients were similar pre- and postoperatively. The quality of life of both cohorts improved considerably and significantly after the treatment, but they remained at a level significantly below that of a general age-matched population.

STUDY DESIGN: Retrospective analysis of prospectively collected data from the National Swedish Spine Register (Swespine).

OBJECTIVE: To evaluate the effects of symptomatic spinal epidural hematoma (SSEH) requiring reoperation on one-year patient-reported outcome measures (PROMs) in a large cohort of patients treated surgically for lumbar spinal stenosis (LSS).

SUMMARY OF BACKGROUND DATA: Studies exploring the outcomes of reoperations after SSEH are scarce and often lack validated outcome measures. As SSEH is considered a serious complication, understanding of the outcome following hematoma evacuation is important.

MATERIALS AND METHODS: After retrieving data from 2007 to 2017 from Swespine, we included all patients with LSS without concomitant spondylolisthesis who were treated surgically with decompression without fusion. Patients with evacuated SSEH were identified in the registry. Back/leg pain numerical rating scales (NRS), the Oswestry Disability Index (ODI), and EQ VAS were used for outcome assessment. PROMs before and one-year after decompression surgery were compared between evacuated patients and all other patients. Multivariate linear regression was performed to determine if hematoma evacuation predicted inferior one-year PROM scores.

RESULTS: A total of 113 patients with an evacuated SSEH were compared with 19527 patients with no evacuation. One-year after decompression surgery, both groups showed significant improvement in all PROMs. When comparing the two groups' one-year improvement there were no significant differences in any PROM. The proportion of patients achieving the minimum important change was not significantly different for any PROM. Multivariate linear regression found that hematoma evacuation significantly predicted inferior one-year ODI (β=4.35, P=0.043), but it was not a significant predictor of inferior NRS Back (β=0.50, P=0.105), NRS Leg (β=0.41, P=0.221), or EQ VAS (β=-1.97, P=0.470). CONCLUSIONS: A surgically evacuated SSEH does not affect outcome in terms of back/leg pain or health-related quality of life. Commonly used PROM surveys may not capture neurologic deficits associated with SSEH.

BACKGROUND AND PURPOSE: There is conflicting evidence regarding treatment outcomes after minimally invasive sacroiliac joint fusion for long-lasting severe sacroiliac joint pain. The primary aim of our cohort study was to investigate change in patient-reported outcome measures (PROMs) after minimally invasive sacroiliac joint surgery in daily practice in the Swedish Spine Registry. Secondary aims were to explore the proportion of patients reaching a patient acceptable symptom score (PASS) and the minimal clinically important difference (MCID) for pain scores, physical function, and health-related quality of life outcomes; furthermore, to evaluate self-reported satisfaction, walking distance, and changes in proportions of patients on full sick leave/disability leave and report complications and reoperations.

METHODS: Data from the Swedish Spine Registry was collected for patients with first-time sacroiliac joint fusion, aged 21 to 70 years, with PROMs available preoperatively, at 1 or 2 years after last surgery. PROMs included Oswestry Disability Index (ODI), Numeric Rating Scale (NRS) for low back pain (LBP) and leg pain, and EQ-VAS, in addition to demographic variables. We calculated mean change from pre- to postoperative and the proportion of patients achieving MCID and PASS.

RESULTS: 68 patients had available pre- and postoperative data, with a mean age of 45 years (range 25-70) and 59 (87%) were female. At follow-up the mean reduction was 2.3 NRS points (95% confidence interval [CI] 1.6-2.9; P < 0.001) for LBP and 14.8 points (CI 10.6-18.9; P < 0.001) for ODI. EQ-VAS improved by 22 points (CI 15.4-30.3, P < 0.001) at follow-up. Approximately half of the patients achieved MCID and PASS for pain (MCID NRS LBP: 38/65 [59%] and PASS NRS LBP: 32/66 [49%]) and physical function (MCID ODI: 27/67 [40%] and PASS ODI: 24/67 [36%]). The odds for increasing the patient's walking distance to over 1 km at follow-up were 3.5 (CI 1.8-7.0; P < 0.0001), and of getting off full sick leave or full disability leave was 0.57 (CI 0.4-0.8; P = 0.001). In the first 3 months after surgery 3 complications were reported, and in the follow-up period 2 reoperations.

CONCLUSION: We found moderate treatment outcomes after minimally invasive sacroiliac joint fusion when applied in daily practice with moderate pain relief and small improvements in physical function.

AIMS: Lumbar disc prolapse is a frequent indication for surgery. The few available long-term follow-up studies focus mainly on repeated surgery for recurrent disease. The aim of this study was to analyze all reasons for additional surgery for patients operated on for a primary lumbar disc prolapse.

METHODS: We retrieved data from the Swedish spine register about 3,291 patients who underwent primary surgery for a lumbar disc prolapse between January 2007 and December 2008. These patients were followed until December 2020 to record all additional lumbar spine operations and the reason for them.

RESULTS: In total, 681 of the 3,291 patients (21%) needed one or more additional operations. More than three additional operations was uncommon (2%; 15/906). Overall, 906 additional operations were identified during the time period, with a mean time to the first of these of 3.7 years (SD 3.6). The most common reason for an additional operation was recurrent disc prolapse (47%; 426/906), followed by spinal stenosis or degenerative spondylolisthesis (19%; 176/906), and segmental pain (16%; 145/906). The most common surgical procedures were revision discectomy (43%; 385/906) and instrumented fusion (22%; 200/906). Degenerative spinal conditions other than disc prolapse became a more common reason for additional surgery with increasing length of follow-up. Most patients achieved the minimally important change (MIC) for the patient-reported outcomes after the index surgery. After the third additional spinal operation, only 20% (5/25) achieved the MIC in terms of leg pain, and 29% (7/24) in terms of the EuroQol five-dimension index questionnaire visual analogue scale.

CONCLUSION: More than one in five patients operated on for a lumbar disc prolapse underwent further surgery during the 13-year follow-up period. Recurrent disc prolapse was the most common reason for additional surgery, followed by spinal stenosis and segmental pain. This study shows that additional operations after primary disc surgery are needed more frequently than previously reported, and that the outcome profoundly deteriorates after the second additional operation. The findings from this study can be used in the shared decision-making process. Cite this article: Bone Joint J 2022;104-B(5):627-632.

PURPOSE: Most patients with lumbar disc herniations requiring surgery have concomitant back pain. The purpose of the current study was to evaluate the outcome of surgery for lumbar disc herniations in patients with no preoperative back pain (NBP) compared to those reporting low back pain (LBP).

METHODS: 15,418 patients surgically treated due to LDH with primary discectomy from 1998 until 2020 were included in the study. Self-reported low back pain assessed with a numerical rating scale (NRS) was used to dichotomize the patients in two groups, patients without preoperative back pain (NBP, NRS = 0, n = 1333, 9%) and patients with preoperative low back pain (LBP, NRS > 0, n = 14,085, 91%). Patient reported outcome measures (PROMs) collected preoperatively and one-year postoperatively were used to evaluate differences in outcomes between the groups.

RESULTS: At the one-year follow-up, 89% of the patients in the NBP group were completely pain free or much better compared with 76% in the LBP group. Significant improvement regarding leg pain was seen in all measured PROMs in both groups oneyear after surgery. In the NBP group, 13% reported clinically significant back pain (NRS difference greater than Minimally Clinical Important Difference (MICD)) at the one-year follow-up.

CONCLUSIONS: Patients without preoperative back pain are good candidates for LDH surgery. 13% of patients without preoperative back pain develop clinically significant back pain one-year after surgery.

PURPOSE: Satisfaction with the outcome of treatment is a widely used outcome measure but information about the determinants of patient satisfaction after surgery for central spinal stenosis (CSS) are lacking. The aim of the study was to analyze determinants of patient satisfaction 1 year after surgery for CSS without degenerative spondylolisthesis (DS).

METHODS: This prospective register study included 5100 patients operated for CSS without DS. 88 % received decompression only (D) and 12 % had decompression and fusion (DF). The patient reported outcome measures were the EuroQol-5D, the Short-Form 36, the visual analogue scale for leg and back pain, the Oswestry disability index and the self-estimated walking distance. Logistic regression reporting odds ratios (OR) for being satisfied was utilized.

RESULTS: There were significant baseline differences between satisfied and dissatisfied patients in all patient reported outcome measures except leg pain. Factors decreasing the likelihood for satisfaction included previous spine surgery OR: 0.4 (95 % CI: 0.3-0.5), smoking OR: 0.6 (95 % CI: 0.4-0.8), unemployment OR: 0.6 (95 % CI: 0.4-0.9), back pain exceeding 1 year OR: 0.6 (95 % CI: 0.4-0.9), back pain predominance OR: 0.7 (95 % CI: 0.5-0.8). Fusion surgery did not predict satisfaction OR: 1.3 (95 % CI: 0.9-1.9). Preoperative self-estimated walking distance >1000 m predicted satisfaction, OR: 2.4 (95 %: 1.6-3.6).

CONCLUSIONS: Numerous factors have predictive value for satisfaction of outcome after surgery for CSS without DS. The results from this study can constitute background data in the shared decision making process when discussing surgery with patients suffering from CSS.

STUDY DESIGN: Descriptive register study.

OBJECTIVE: To describe preoperative levels of leg and back pain in patients operated for lumbar spinal stenosis, and to obtain information on how 3 different pain constellations (back pain < leg pain, back pain > leg pain, back pain = leg pain) correlate to health related quality of life (HRQoL) and function in different morphological types of stenosis.

SUMMARY OF BACKGROUND DATA: Degenerative lumbar spinal stenosis is considered a poorly defined clinical syndrome and knowledge of what uniquely characterizes the different morphological types of stenosis is lacking.

METHODS: Using the Swedish Spine Register, we studied (1) the pain characteristics of patients with central spinal stenosis (CSS), lateral recess stenosis, and spinal stenosis with spondylolisthesis (2) how HRQoL and function correlate to leg and back pain.

RESULTS: Grading leg pain higher than back pain was the most common pain constellation (49%) followed by grading back pain more than leg pain (39%). Twelve percent had the same intensity of leg and back pain. The type of stenosis grading the highest burden of back pain was spinal stenosis with spondylolisthesis (ratio = 0.93; [95% confidence interval, CI] = 0.92-0.95), followed by central spinal stenosis (ratio = 0.88; [95% CI] = 0.88-0.89). Lateral recess stenosis had the lowest burden of back pain (ratio = 0.85; [95% CI] = 0.83-0.87). The lowest HRQoL and function was found in spinal stenosis with spondylolisthesis (back pain = leg pain group) where 55% ([95% CI] = 50-59) of patients could not walk more than 100 m. Patients with lateral recess stenosis had better self-estimated walking distance.

CONCLUSION: Back pain is generally experienced to a high extent by patients scheduled for spinal stenosis surgery. HRQoL and function are low preoperatively irrespective of whether back or leg pain is predominant. In this large patient material patients who grade their back and leg pain as likeworthy have significantly lower values for HRQoL and function compared to patients reporting predominant leg or back pain but the difference is not clinically relevant.

BACKGROUND CONTEXT: Patients with spinal stenosis with concomitant degenerative spondylolisthesis (DS) and predominant back pain (PBP) have been shown to have inferior outcome after surgery. Studies comparing outcome according to preoperative pain predominance and treatment received are lacking.

PURPOSE: The purpose was to study if adding spinal fusion to the decompression in DS affects outcome in patients with PBP (back pain [BP] Visual Analog Scale [VAS] more than or equal to leg pain [LP] VAS) compared with predominant leg pain (PLP) (BP VAS less than LP VAS).

PATIENT SAMPLE: The Swedish Spine Register was used and included 1,624 patients operated for DS at the L4-L5 level.

OUTCOME MEASURES: Self-reported measures were used, including a VAS for BP and LP, the EuroQol-5D (EQ-5D), and the physical and mental component summaries of the Short-Form 36 to estimate health-related quality of life and the Oswestry disability index (ODI) to estimate function.

METHODS: Inclusion criterion was single-level DS operated on with either decompression only (D) or decompression and instrumented posterolateral fusion (DF). Based on preoperative LP and BP scores, the patients were assigned to one of the two groups: LP predominance or BP predominance. The patients completed the outcome protocol at 1- and 2-year follow-ups. Statistical analysis was performed using linear regression adjusting for multiple potential confounders.

RESULTS: In the adjusted outcome at the 1-year follow-up, patients with PLP reported a 7.9-mm more improvement on the VAS for BP with fusion, compared with D (95% confidence interval [CI], 0.7-15.2), p=.03. Despite more change in the fused group, the reported BP levels remained similar in the D versus decompressed and fused at the 1-year follow-up (28 vs. 24, p=.77). The patients with PBP benefited from adding fusion in terms of BP 7.1 (95% CI, 0.3-13.9, p=.04), LP 8.8 (2-15.7, p=.01), the ODI 5.7 (1.6-9.9, p=.006), and the EQ-5D 0.09 (1.7-0.02, p=.02) at the 1-year follow-up as the DF group reported greater change in the outcome compared with the D group. At the 2-year follow-up, no significant differences were found between D and decompressed and fused in either the LP or the PBP groups.

CONCLUSIONS: Patients with PBP operated with DF report better outcomes in terms of pain, function, and health-related quality of life than patients with D. Although these differences are significant on a group level, they may fail to reach minimal clinical significant difference. Patients with PLP report significantly more improvement in terms of BP with DF compared with D, but because of baseline differences in preoperative BP, these improvements may not be explained by the added fusion per se. At the 2-year follow-up, no significant differences were observed between the D and DF patients in either the PBP or PLP groups, but greater loss to follow-up in the DF groups could potentially bias these findings.

STUDY DESIGN: A register cohort study.

OBJECTIVE: To evaluate outcome of surgery for lumbar spinal stenosis without concomitant degenerative spondylolisthesis according to predominance of pain and to analyze the role of spinal fusion in conjunction with decompression in patients with predominant back pain (BP) or leg pain (LP).

SUMMARY OF BACKGROUND DATA: Predominance of BP is associated with inferior outcome of surgery for central spinal stenosis. It is unknown if using spinal fusion improves outcomes.

METHODS: In a register study of 9051 patients, we studied outcome of surgery in terms of BP and LP visual analogue scale, function (the Oswestry Disability Index and self-estimated walking distance), health-related quality of life (Short-Form 36 and EuroQol), and patient satisfaction. Outcome was analyzed for 4 groups at 1- and 2-year follow-ups; preoperative BP was equal to or worse than LP and decompression, preoperative BP was equal to or worse than LP and decompression and fusion, preoperative BP was less than LP and decompression, preoperative BP was less than decompression and fusion.

RESULTS: Patients with concomitant fusion were younger and had higher BP and Oswestry Disability Index scores and lower preoperative EuroQol. Predominant BP was associated with inferior outcome in terms of pain, health-related quality of life, and function. Patients most often satisfied (69%) were patients with BP less than LP treated with decompression and fusion and the least satisfied group was patients with BP equal to or worse than LP treated with decompression (54%). Fusion was not only associated with higher EuroQol at 1-year follow-up for patients with predominant BP, but also associated with increased LP at 2-year follow-up in patients with predominant LP. Patients with predominant BP experienced small gains in the physical component summary with fusion.

CONCLUSION: Predominance of BP is associated with inferior outcome. Using spinal fusion improves unadjusted outcome but the benefit is small and not clinically significant and generally disappears in the adjusted analysis.

LEVEL OF EVIDENCE: 4.

BACKGROUND AND PURPOSE: MRI is the modality of choice when diagnosing spinal stenosis but it also shows that stenosis is prevalent in asymptomatic subjects over 60. The relationship between preoperative health-related quality of life, functional status, leg and back pain, and the objectively measured dural sac area in single and multilevel stenosis is unknown. We assessed this relationship in a prospective study.

PATIENTS AND METHODS: The cohort included 109 consecutive patients with central spinal stenosis operated on with decompressive laminectomy or laminotomy. Preoperatively, all patients completed the questionnaires for EQ-5D, SF-36, Oswestry disability index (ODI), estimated walking distance and leg and back pain (VAS). The cross-sectional area of the dural sac was measured at relevant disc levels in mm², and spondylolisthesis was measured in mm. For comparison, the area of the most narrow level, the number of levels with dural sac area < 70 mm², and spondylolisthesis were studied.

RESULTS: Before surgery, patients with central spinal stenosis had low HRLQoL and functional status, and high pain levels. Patients with multilevel stenosis had better general health (p = 0.04) and less leg and back pain despite having smaller dural sac area than patients with single-level stenosis. There was a poor correlation between walking distance, ODI, the SF-36, EQ-5D, and leg and back pain levels on the one hand and dural sac area on the other. Women more often had multilevel spinal stenosis (p = 0.05) and spondylolisthesis (p < 0.001). Spondylolisthetic patients more often had small dural sac area (p = 0.04) and multilevel stenosis (p = 0.06).

INTERPRETATION: Our findings indicate that HRQoL, function, and pain measured preoperatively correlate with morphological changes on MRI to a limited extent.

BACKGROUND AND PURPOSE: A considerable number of patients who undergo surgery for spinal stenosis have residual symptoms and inferior function and health-related quality of life after surgery. There have been few studies on factors that may predict outcome. We tried to find predictors of outcome in surgery for spinal stenosis using patient- and imaging-related factors.

PATIENTS AND METHODS: 109 patients in the Swedish Spine Register with central spinal stenosis that were operated on by decompression without fusion were prospectively followed up 1 year after surgery. Clinical outcome scores included the EQ-5D, the Oswestry disability index, self-estimated walking distance, and leg and back pain levels (VAS). Central dural sac area, number of levels with stenosis, and spondylolisthesis were included in the MRI analysis. Multivariable analyses were performed to search for correlation between patient-related and imaging factors and clinical outcome at 1-year follow-up.

RESULTS: Several factors predicted outcome statistically significantly. Duration of leg pain exceeding 2 years predicted inferior outcome in terms of leg and back pain, function, and HRLQoL. Regular and intermittent preoperative users of analgesics had higher levels of back pain at follow-up than those not using analgesics. Low preoperative function predicted low function and dissatisfaction at follow-up. Low preoperative EQ-5D scores predicted a high degree of leg and back pain. Narrow dural sac area predicted more gains in terms of back pain at follow-up and lower absolute leg pain.

INTERPRETATION: Multiple factors predict outcome in spinal stenosis surgery, most importantly duration of symptoms and preoperative function. Some of these are modifiable and can be targeted. Our findings can be used in the preoperative patient information and aid the surgeon and the patient in a shared decision making process.

Brugada Syndrome (BrS) is a genetic condition associated with ventricular fibrillation and sudden cardiac death. In BrS, several pharmacological agents may increase the risk for arrhythmia and total intravenous anesthesia with propofol (TIVA) may be contraindicated due to the increased risk of perioperative cardiac arrest. Anesthesia with halogenated volatile agents has to be used instead, making monitoring of sensory and motor evoked potentials in spine surgery problematic. Furthermore, hyperthermia may induce ventricular arrhythmia in BrS, thus making temperature control of paramount importance. The purpose of this paper is to describe the particular challenges of anesthesia and intraoperative neuromonitoring associated with corrective spinal surgery in an adolescent girl with BrS. We present an analysis of a multidisciplinary approach to performing corrective spine surgery in an otherwise healthy 14-year-old girl with scoliosis. Before surgery, multidisciplinary meetings were conducted, including anesthesia and intensive care, pediatric cardiology as well as the spine team. The surgery was performed with inhalation anesthesia using sevoflurane and cardiac monitoring. Continuous somatosensory potentials were monitored as well as motor evoked potentials. The patient underwent corrective surgery from Th3 to L2. With a multidisciplinary team approach involving anesthesia and cardiology outlining the appropriate precautions, scoliosis correction with intraoperative neuromonitoring, can be safely performed in patients with BrS using inhalation anesthesia.

Study Design: Prospective register cohort study.

Objectives: The indication for surgery in patients with lumbar spinal stenosis (LSS) is considered to be leg pain and neurogenic claudication (NC). Nevertheless, a significant part of patients operated for LSS have mild leg pain levels defined as leg pain <= minimally important clinical difference (MICD). Information is lacking on how to inform these patients about the probable outcome of surgery. The objective was to report the outcome of surgery for LSS in patients with a mild preoperative level of leg pain.

Methods: A total of 2559 patients operated upon for LSS with preoperative leg pain <= 3 NRS (Numerical Rating Scale) were evaluated for outcome at the 1-year follow-up. NRS for back pain, the Oswestry Disability Index (ODI), and the EuroQol (EQ-5D) were used.

Results: In the period 2007 to 2017, we identified 3239 patients (14%) who had mild leg pain (<= 3 on the NRS). In this cohort, leg pain increased 0.40 (0.56-0.37) and back pain decreased 1.0 (0.95-1.2) at the 1-year follow up. ODI decreased 11.1 (10.2-11.4) and the EQ-5D increased 0.15 (0.17-0.14). A total of 31% reached successful outcome in terms of back pain, 43% in terms of ODI and 48% in terms of EQ-5D. 63% of the patients were satisfied with the outcome.

Conclusion: A minority of patients with mild leg pain levels operated upon for LSS attain MICD for back pain, ODI, and EQ-5D. The results from this study can aid the surgeon in the shared decision-making process before surgery.

INTRODUCTION: Rupture of the distal tendon of the biceps muscle is a rare injury. If unrepaired the patient will be left with weakness of supination of the arm and flexion in the elbow. Long term results for the 2-incision approach for tendon reinsertion are few but in this study we describe the long term, clinical, functional, and subjective results of surgical repair using the 2-incision method described by Boyd and Anderson.

MATERIAL AND METHODS: All patients who were operated at FSA hospital during the years 1986-2000 because of rupture of the distal tendon of the biceps muscle were asked to participate in the study. Twelve of 16 patients accepted and answered the DASH questionnaire. Strength was tested with handheld dynamometer and ROM where measured. Radiograph was taken of the affected arm.

RESULTS: From 1986 through 2006 we operated on 16 patients because of rupture of the distal biceps tendon, one female and 15 male. Mean age at the time of rupture was 46 years (24-53).The average follow up were seven years (1-17). Ten of 12 patients were operated within two weeks from the injuries. No difference in strength was found between operated and non-operated arms. Late repair was associated with high DASH score and poor subjective results. Six patients developed heterotopic ossification but none of them developed radioulnar synostosis. One reoperation because entrapment of the median nerve was done.

CONCLUSIONS: Despite heterotopic ossification and a small ROM deficit the Boyd and Anderson technique for repair of distal biceps ruptures yields good long term results in a low volume rural hospital. Early diagnosis and tendon reinsertion is of great importance to avoid persistent anterior elbow pain and poor subjective results.

This case report describes a 66-year old woman with Parkinson´s disease and a subacute onset lateral postural deformity. She experienced severe back pain and reduced walking ability. She was diagnosed with Pisa syndrome and sagittal and coronal imbalance was observed on radiographs. Posterior reconstructive surgery was performed from sacrum to Th10. Post operatively, sagittal and coronal imbalance was improved and maintained at the two year follow-up. The patient remained pain free and improvements in walking ability were sustained. The caveats of spine surgery in Parkinson´s patients are discussed and the importance of goal oriented surgery in terms of improvements in sagittal and coronal balance.

BACKGROUND: Incidental durotomy (ID) is one of the most common intraoperative complications seen in spine surgery. Conflicting evidence has been presented regarding whether or not outcomes are affected by the presence of an ID.

PURPOSE: To evaluate whether outcomes following degenerative spine surgery are affected by ID and the incidence of ID with different diagnoses and different surgical procedures.

MATERIALS: By using SweSpine, the national Swedish Spine Surgery Register, preoperative, surgical and postoperative 1-year follow-up data were obtained for 64,431 surgeries. All patients were surgically treated due to lumbar spinal stenosis (LSS) without or with concomitant degenerative spondylolisthesis (DS) or lumbar disc herniation (LDH) between 2000 and 2015. Gender, age, smoking habits, walking distance, consumption of analgesics, back and leg pain (Visual Analogue Scale [VAS]), quality of life (EuroQol [EQ5D] and Short Form 36 [SF-36]), and disability (Oswestry Disability Index [ODI]) were recorded.

RESULTS: Overall, incidence of ID during the study period was 5.0%. For the LDH, LSS, and DS subgroups, it was 2.8%, 6.5%, and 6.5%, respectively. Laminectomy was associated with a higher incidence of ID than discectomy (p<.001). ID was more common in all three subgroups if the patient had previously been subjected to spine surgery and with increasing age of the patients (p<.001). LDH patients with an ID reported a higher degree of residual leg pain, inferior mental quality of life (SF-36 MCS), and higher disability (ODI) than LDH patients without ID (all p<.001) 1-year after surgery. LSS patients with an ID reported inferior SF-36 MCS (p<.001) and DS patients with an ID had inferior SF-36 MCS and higher ODI compared to patients with the same diagnosis but without an ID (p<.001). However, these numerical differences are well below references for MCID, for all three subgroups. ID was associated with a higher frequency of patients being dissatisfied with the surgical outcome at 1-year follow-up. In patients who did not improve in back and leg pain following surgery (delta-value), ID was less common than in patients reporting improved back and leg pain from before as compared to following surgery.

CONCLUSIONS: The overall occurrence of ID in the present study was 5%, with higher figures in LSS and DS and lower figures in LDH. Higher age of the patient and previous surgery were associated with higher frequencies of ID. The outcome at 1 year following surgery was not affected to a clinically relevant extent when an ID was obtained. However, ID was associated with a higher degree of patient dissatisfaction and a longer hospital length of stay.

PURPOSE: Previous studies have suggested that genetic factors are important in the development of degenerative disk disease (DDD). However, the concordance rates for the phenotypes requiring surgery are unknown. The purpose of this study was to determine the concordance rates for DDD requiring surgery by studying monozygotic (MZ) and dizygotic (DZ) twin pairs.

METHODS: Patients, aged between 18 and 85 years, operated for DDD between 1996 and 2022 were identified in the national Swedish spine register (Swespine) and matched with the Swedish twin registry (STR) to identify MZ and DZ twins. Pairwise and probandwise concordance rates were calculated.

RESULTS: We identified 11,207 patients, 53% women, operated for DDD. By matching the Swespine patients with the STR, we identified 121 twin pairs (37 MZ and 84 DZ) where one or both twins were surgically treated for DDD. The total twin incidence for operated DDD was 1.1%. For DDD requiring surgery, we found no concordant MZ pair and no concordant DZ pair where both twins were operated for DDD. When we evaluated pairs where at least one twin was operated for DDD, we found two concordant MZ pairs (the co-twins were operated for spinal stenosis) and two  concordant DZ pairs (one co-twin operated for spinal stenosis and one (co-twin operated for disk herniation).

CONCLUSIONS: Our findings suggest that genetic factors are probably not a major etiologic component in most cases of DDD requiring surgery. The findings of this study can be used for counseling patients about the risk for requiring DDD surgery.

BACKGROUND: There is growing evidence to suggest a potential genetic component underlying the development and progression of lumbar spine diseases. However, the heritability and the concordance rates for the phenotypes requiring surgery for the common spine diseases lumbar spinal stenosis (LSS) and lumbar disc herniation (LDH) are unknown. The aim of this study was to determine the heritability and the concordance rates for LSS and LDH requiring surgery by studying monozygotic (MZ) and dizygotic (DZ) twin pairs.

METHODS: Patients between 18 and 85 years of age who underwent surgery for LSS or LDH between 1996 and 2022 were identified in the national Swedish spine registry (LSS: 45,110 patients; LDH: 39,272 patients), and matched with the Swedish Twin Registry to identify MZ and DZ twins. Pairwise and probandwise concordance rates, heritability estimates, and MZ/DZ concordance ratios were calculated.

RESULTS: We identified 414 twin pairs (92 MZ and 322 DZ pairs) of whom 1 or both twins underwent surgery for LSS. The corresponding number for LDH was 387 twin pairs (118 MZ and 269 DZ pairs). The probandwise concordance rate for LSS requiring surgery was 0.25 (26 of 105) (95% confidence interval [CI], 0.14 to 0.34) for MZ twins and 0.04 (12 of 328) (95% CI, 0.01 to 0.07) for DZ twins. The corresponding values for LDH requiring surgery were 0.03 (4 of 120) (95% CI, 0 to 0.08) and 0.01 (4 of 271) (95% CI, 0 to 0.04), respectively. The probandwise MZ/DZ concordance ratio was 6.8 (95% CI, 2.9 to 21.5) for LSS and 2.3 (95% CI, 0 to 8.9) for LDH. The heritability was significantly higher in LSS compared with LDH (0.64 [95% CI, 0.50 to 0.74] versus 0.19 [95% CI, 0.08 to 0.35]).

CONCLUSIONS: Our findings suggest that genetic factors may play an important role in the risk of developing LSS requiring surgery, whereas heredity seems to be of less importance in LDH requiring surgery. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

BACKGROUND: Acute bilateral vocal fold paralysis is a life-threatening complication that can occur during spinal surgery but has almost exclusively occurred with anterior approaches. Bilateral vocal fold paralysis after posterior spinal surgery has been exceedingly rare.

CASE DESCRIPTION: We present a case of acute postoperative dyspnea due to vocal fold paralysis requiring intubation and surgical intervention after posterior spinal correction for the treatment of dropped head syndrome. The patient had had a previous diagnosis of atypical Parkinson disease but was later diagnosed with multiple system atrophy.

CONCLUSIONS: We suggest that multiple system atrophy can result in an increased risk of bilateral vocal fold paralysis during surgical intervention of dropped head syndrome. Thus, our report could be of interest for those who perform spinal surgery in patients with neurological conditions.