To Örebro University

STUDY DESIGN: A retrospective analysis of prospectively collected registry data.

OBJECTIVE: To examine the subsequent pattern of surgeries and outcome of sacroiliac joint fusions (SJF) in patients previously operated in the lumbar spine as well as those scheduled for primary SJF.

SUMMARY OF BACKGROUND DATA: Patients with SI joint pain often have a history of previous back surgery, but it is unclear how often patients require back surgery after SI-joint fusion.

METHODS: We obtained data from the national Swedish spine registry on all patients who underwent a SJF between 1998 and 2019 and identified previous and additional operations of any type after a SJF between 1998 and 2022. The EuroQol EQ VAS and the Oswestry disability index (ODI) were registered preoperatively and 1 year after the last undergone surgery. Satisfaction with treatment was assessed 1 year after surgery.

RESULTS: Two hundred seventy-nine patients underwent SJF between 1998 and 2019. Ninety-five of 279 patients (34%) underwent primary SJF, and 184 of 279 patients (66%) underwent SJF after spine surgery. Forty-one of 95 patients (43%) underwent additional spine or SI-joint surgery after a primary SJF. The most common additional procedure was contralateral SJF (22 of 41; 54%). The mean EQ-VAS change after primary SJF was 19 points (95% CI 12-26), whereas the corresponding value for SJF after previous lumbar spine surgery was 9 points (95% CI 2-16). The corresponding values for the mean ODI change were -14 points (95% CI -19 to -10) and -9 points (95% CI -14 to -4) respectively. Seventy-three percent (37 of 51) and 54% (34 of 63) were satisfied after SJF after primary versus secondary SJF.

CONCLUSION: After primary SJF most additional surgeries are for contralateral symptoms and 9% required lumbar surgery after their SJF. Two-thirds of the patients with SJF have had their surgery after lumbar surgery.

BACKGROUND: Only a few studies have investigated the genetic background of lumbar spinal stenosis (LSS) with degenerative spondylolisthesis (DS) requiring surgery. The purpose of this study was to determine the concordance rates for LSS with DS 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 with DS between 1996 and 2022 were identified in the national Swedish spine registry (14,614 patients) and matched with the Swedish Twin Registry to identify MZ and DZ twins. The concordance rates, the MZ/DZ concordance ratios, and the limits of genetic determination were calculated.

RESULTS: We identified 145 twin pairs (27 MZ and 118 DZ pairs) of whom 1 or both twins underwent surgery for LSS with DS. We found no concordant MZ pair and 2 concordant DZ pairs. When we evaluated pairs where at least one twin was operated for LSS with DS we found 2 concordant MZ pairs and 4 concordant DZ pairs (the co-twins were operated for LSS without DS) resulting in the probandwise concordance rate 0.14 (95% CI, 0 to 0.31) for MZ twins and 0.07 (95% CI, 0.02 to 0.13) for DZ twins. The probandwise MZ/DZ concordance ratio was 2.1 (95% CI 0-11.9). The limits of genetic determination were 0.27 to 0.36.

CONCLUSIONS: Our findings suggest that heredity may not be of major etiologic importance in most cases of LSS with DS requiring surgery.

PURPOSE: Genetic factors are considered important in the development of degenerative spine disease. The aim of this study was to determine the twin concordance rates for the common cervical spine diseases cervical disk herniation (CDH), cervical foraminal stenosis (CFS), and degenerative cervical myelopathy (DCM) requiring surgical treatment by studying monozygotic (MZ) and dizygotic (DZ) twin pairs.

METHODS: Patients, aged 18-85 years, operated for CDH, CFS, or DCM between 1996 and 2022 were identified in the national Swedish spine register (5962 CDH, 3801 CFS, and 3131 DCM) and matched with the Swedish twin registry to identify MZ and DZ twins. Concordance rates were calculated.

RESULTS: There were 64 twin pairs where one or both twins had surgical treatment for CDH. The corresponding numbers for surgically treated CFS and DCM were 37 twin pairs and 44 twin pairs respectively. For twins with CDH we found one concordant MZ pair and no concordant DZ pair (MZ probandwise concordance rate 0.12 [95% CI 0-0.33]). For twins with CFS we found one concordant MZ pair and no concordant DZ pair (MZ probandwise concordance rate 0.14 [95% CI 0-0.38]). In DCM patients we found no concordant twin pair.

CONCLUSIONS: In this national observational study, including 145 twin pairs, the concordance rates were low for surgically treated CDH, CFS, and DCM conditions. Our findings suggest that not only genetic factors, but also environmental factors and personal preferences are important whether a patient goes to surgery for this type of condition.

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.

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.

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.

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.