Are there differences in the reoperation rates for operative adjacent-segment disease between ALIF+PS, PLIF+PS, TLIF+PS, and LLIF+PS? An analysis of a cohort of 5291 patients.

OBJECTIVE: Biomechanical factors in lumbar fusions accelerate the development of adjacent-segment disease (ASD). Stiffness in the fused segment increases motion in the adjacent levels, resulting in ASD. The objective of this study was to determine if there are differences in the reoperation rates for symptomatic ASD (operative ASD) between anterior lumbar interbody fusion plus pedicle screws (ALIF+PS), posterior lumbar interbody fusion plus pedicle screws (PLIF+PS), transforaminal lumbar interbody fusion plus pedicle screws (TLIF+PS), and lateral lumbar interbody fusion plus pedicle screws (LLIF+PS). METHODS: A retrospective study using data from the Kaiser Permanente Spine Registry identified an adult cohort (≥ 18 years old) with degenerative disc disease who underwent primary lumbar interbody fusions with pedicle screws between L3 to S1. Demographic and operative data were obtained from the registry, and chart review was used to document operative ASD. Patients were followed until operative ASD, membership termination, the end of study (March 31, 2022), or death. Operative ASD was analyzed using Cox proportional hazards models. RESULTS: The final study population included 5291 patients with a mean ± SD age of 60.1 ± 12.1 years and a follow-up of 6.3 ± 3.8 years. There was a total of 443 operative ASD cases, with an overall incidence rate of reoperation for ASD of 8.37% (95% CI 7.6-9.2). The crude incidence of operative ASD at 5 years was the lowest in the ALIF+PS cohort (7.7%, 95% CI 6.3-9.4). In the adjusted models, the authors failed to detect a statistical difference in operative ASD between ALIF+PS (reference) versus PLIF+PS (HR 1.06 [0.79-1.44], p = 0.69) versus TLIF+PS (HR 1.03 [0.81-1.31], p = 0.83) versus LLIF+PS (HR 1.38 [0.77-2.46], p = 0.28). CONCLUSIONS: In a large cohort of over 5000 patients with an average follow-up of > 6 years, the authors found no differences in the reoperation rates for symptomatic ASD (operative ASD) between ALIF+PS and PLIF+PS, TLIF+PS, or LLIF+PS.

Temporal Trends in Deep Surgical Site Infections After Six Orthopaedic Procedures Over a 12-year Period Within a US-based Healthcare System.

INTRODUCTION: Centers of excellence and bundled payment models have driven perioperative optimization and surgical site infection (SSI) prevention with decolonization protocols and antibiotic prophylaxis strategies. We sought to evaluate time trends in the incidence of deep SSI and its causative organisms after six orthopaedic procedures in a US-based integrated healthcare system. METHODS: We conducted a population-level time-trend study using data from Kaiser Permanente's orthopaedic registries. All patients who underwent primary anterior cruciate ligament reconstruction (ACLR), total knee arthroplasty (TKA), elective total hip arthroplasty (THA), hip fracture repair, shoulder arthroplasty, and spine surgery were identified (2009 to 2020). The annual incidence of 90-day deep SSI was identified according to the National Healthcare Safety Network/Centers for Disease Control and Prevention guidelines with manual chart validation for identified infections. Poisson regression was used to evaluate annual trends in SSI incidence with surgical year as the exposure of interest. Annual trends in overall incidence and organism-specific incidence were considered. RESULTS: The final study sample was composed of 465,797 primary orthopaedic procedures. Over the 12-year study period, a decreasing trend in deep SSI was observed for ACLR and hip fracture repair. Although there was variation in incidence rates for specific operative years for TKA, elective THA, shoulder arthroplasty, and spine surgery, no consistent decreasing trends over time were found. Decreasing rates of Staphylococcus aureus infections over time after hip fracture repair, shoulder arthroplasty, and spine surgery and decreasing trends in antibiotic resistance after elective THA and spine surgery were also observed. Increasing trends of polymicrobial infections were observed after TKA and Cutibacterium acnes after elective THA. CONCLUSIONS: The overall incidence of deep SSI after six orthopaedic procedures was rare. Decreasing SSI rates were observed for ACLR and hip fracture repair within our US-based healthcare system. Polymicrobial infections after TKA and Cutibacterium acnes after elective THA warrant closer surveillance. LEVEL OF EVIDENCE: IV.

No Difference in Reoperation Rates for Adjacent Segment Disease (Operative Adjacent Segment Disease) in Posterior Cervical Fusions Stopping at C7 Versus T1/T2: A Cohort of 875 Patients-Part 1.

STUDY DESIGN: A retrospective cohort study with chart review. OBJECTIVE: To determine whether there is a difference in reoperation rates for adjacent segment disease ([ASD] operative ASD) in posterior cervical fusions (PCFs) that stop at -C7 versus -T1/T2. SUMMARY OF BACKGROUND DATA: There are surgical treatment challenges to the anatomical complexities of the cervicothoracic junction. Current posterior cervical spine surgery is based on the belief that ASD occurs if fusions are stopped at C7 although there is varying evidence to support this assumption. METHODS: Patients were followed until validated reoperations for ASD, membership termination, death, or March 31, 2020. Descriptive statistics and 5-year crude incidence rates and 95% confidence intervals for operative ASD for PCF ending at -C7 or -T1/T2 were reported. Time-dependent crude and adjusted multivariable Cox-Proportional Hazards models were used to evaluate operative ASD rates with adjustment for covariates or risk change estimates more than 10%. RESULTS: We identified 875 patients with PCFs (beginning at C3 or C4 or C5 or C6) stopping at either -C7 (n = 470) or -T1/T2 (n = 405) with average follow-up time of 4.6 (±3.3) years and average time to operative ASD of 2.7 (±2.8) years. Crude overall incidence rates for stopping at -C7 (2.12% [1.02%-3.86%]) and -T1/T2 (2.48% [1.25%-4.40%]) were comparable with no statistical difference in risk (adjusted hazard ratio = 1.47, 95% confidence interval = 0.61-3.53, P = 0.39). In addition, we observed no differences in the probability of operative ASD in competing risk time-dependent models (Grey test P  = 0.448). CONCLUSION: A large cohort of 875 patients with PCFs stopping at -C7 or -T1/T2 with an average follow-up of more than 4 years found no statistical difference in reoperation rates for ASD (operative ASD).Level of Evidence: 3.

No difference in reoperation rates for nonunions (operative nonunions) in posterior cervical fusions stopping at C7 versus T1/2: a cohort of 875 patients.

OBJECTIVE: The challenges of posterior cervical fusions (PCFs) at the cervicothoracic junction (CTJ) are widely known, including the development of adjacent-segment disease by stopping fusions at C7. One solution has been to cross the CTJ (T1/T2) rather than stopping at C7. This approach may have undue consequences, including increased reoperations for symptomatic nonunion (operative nonunion). The authors sought to investigate if there is a difference in operative nonunion in PCFs that stop at C7 versus T1/T2. METHODS: A retrospective analysis identified patients from the authors' spine registry (Kaiser Permanente) who underwent PCFs with caudal fusion levels at C7 and T1/T2. Demographics, diagnoses, operative times, lengths of stay, and reoperations were extracted from the registry. Operative nonunion was adjudicated via chart review. Patients were followed until validated operative nonunion, membership termination, death, or end of study (March 31, 2020). Descriptive statistics and 2-year crude incidence rates and 95% confidence intervals for operative nonunion for PCFs stopping at C7 or T1/T2 were reported. Time-dependent crude and adjusted multivariable Cox proportional hazards models were used to evaluate operative nonunion rates. RESULTS: The authors identified 875 patients with PCFs (beginning at C3, C4, C5, or C6) stopping at either C7 (n = 470) or T1/T2 (n = 405) with a mean follow-up time of 4.6 ± 3.3 years and a mean time to operative nonunion of 0.9 ± 0.6 years. There were 17 operative nonunions, and, after adjustment for age at surgery and smoking status, the cumulative incidence rates were similar between constructs stopping at C7 and those that extended to T1/T2 (C7: 1.91% [95% CI 0.88%-3.60%]; T1/T2: 1.98% [95% CI 0.86%-3.85%]). In the crude model and model adjusted for age at surgery and smoking status, no difference in risk for constructs extended to T1/T2 compared to those stopping at C7 was found (adjusted HR 1.09 [95% CI 0.42-2.84], p = 0.86). CONCLUSIONS: In one of the largest cohort of patients with PCFs stopping at C7 or T1/T2 with an average follow-up of > 4 years, the authors found no statistically significant difference in reoperation rates for symptomatic nonunion (operative nonunion). This finding shows that there is no added risk of operative nonunion by extending PCFs to T1/T2 or stopping at C7.

PLF+PS or ALIF+PS: which has a lower operative nonunion rate? Analysis of a cohort of 2,061 patients from a National Spine Registry.

BACKGROUND CONTEXT: Although fusion rates in posterolateral lumbar fusions with pedicle screws (PLF+PS) and anterior lumbar interbody fusions with pedicle screws (ALIF+PS) have been reported, there has been no consensus on superiority with respect to clinical outcome and nonunion rates. Most studies determine nonunion rates based on radiographic studies; however, many of these nonunions are asymptomatic and may not require reoperations. Hence, a potentially more clinically useful measure is the reoperation rate for symptomatic nonunions, which we term the operative nonunion rate. PURPOSE: To determine if there is a difference in operative nonunion rates between PLF+PS versus ALIF+PS. STUDY DESIGN: Retrospective cohort study. PATIENT SAMPLE: Adult patients (≥18 years old) with the diagnosis of lumbar spondylolisthesis or lumbar spinal stenosis who underwent primary elective PLF+PS and ALIF+PS for 1-level and 2-level fusions (L4-S1) between 2009 and 2018. OUTCOME MEASURES: Reoperation rates for symptomatic nonunions (ie, operative nonunion rates). METHODS: Patients were followed until validated operative nonunions, membership termination, death, or 03/31/2019. Descriptive statistics and 2-year incidence rates for operative nonunions were calculated by fusion-level, fusion type, and levels fused. Time-dependent multivariable Cox-Proportional Hazards regression was used to evaluate operative nonunion rates with adjustment for covariates or risk change estimates more than 10%. RESULTS: We identified 2,061 patients (PLF+PS:1,491, ALIF+PS:570) with average follow-up time of 4.8 (±3.1) years and average time to operative nonunion of 1.3 (±1.2) yrs. Comparatively, unadjusted 1-level and 2-level incidence rates for operative nonunions were higher in PLF+PS versus ALIF+PS. For 1-level procedures these were 0.9% (95% CI=0.4-1.6) versus 0.6% (95% CI=0.1-2.1); 2-level, 2.0% (95% CI=0.8-4.0) versus 0.9% (95% CI=0.1-3.3). However, there were no observed significant differences in risks for operative nonunions in multivariable models comparing PLF+PS versus ALIF+PS (HR=0.3, 95% CI=0.1-1.1), 1-level versus 2-level fusions (HR=1.8, 95% CI=0.8-4.3), or by fusion level (L4-L5: HR=1.0, 95% CI=0.4-2.7; L5-S1: HR=2.0, 95% CI=0.7-5.4). CONCLUSIONS: A large cohort of patients with lumbar fusions between L4 to S1 and an average follow-up of >4 years found that although there was a trend for higher operative nonunions in PLF+PS compared with ALIF+PS, this was not statistically significant. The role of spinal alignment was not investigated.

Operative Nonunion Rates in Posterolateral Lumbar Fusions: Analysis of a Cohort of 2591 Patients from a National Spine Registry.

OBJECTIVE: Radiographic nonunion rates in the literature for posterolateral lumbar fusions with pedicle screws (PLFs) range from 8.1% to 43.3% but may not represent nonunion rates. A few small studies have reported reoperations for symptomatic nonunions (operative nonunions) to range from 3.2% to 13.9%. The objective of this study is to determine operative nonunion rates for 1-level, 2-level, 3-level, and ≥4-level PLFs and to determine the risks for these nonunions. METHODS: A retrospective cohort study, using data from the Kaiser Permanente Spine Registry, identified adult patients (≥18 years old) who underwent PLFs for degenerative disc disease. Multivariable Cox proportional hazards regression and Kaplan-Meier survival estimates using the log-rank statistic were used to evaluate operative nonunion rates. RESULTS: The cohort consisted of 2591 patients with single-level and multilevel PLFs with mean follow-up of 4.6 years, time to operative nonunion of 1.52 years, and 2-year operative nonunion rate of 1.08%. Compared with single-level fusions, patients with 3-level and ≥4-level fusion had 2.8 and 3.7 times higher risk of operative nonunions. Patients with PLFs involving L5-S1 had 2.5 times the risk of an operative nonunion compared with those without. CONCLUSIONS: Our study reports results from one of the largest cohort of patients for the first time with single-level and multilevel instrumented PLFs and found a 2-year operative nonunion rate of 1.08% with increased risk of nonunion for constructs that included L5-S1 and ≥3-level fusions. Operative nonunion combines clinical and radiographic data and provides an alternative measure of fusion rates.

PLF Versus PLIF and the Fate of L5-S1: Analysis of Operative Nonunion Rates Among 3065 Patients with Lumbar Fusions from a Regional Spine Registry.

STUDY DESIGN: A retrospective cohort study with chart review. OBJECTIVE: The aim of this study was to compare the reoperation rates for symptomatic nonunions (operative nonunion rates) between posterolateral fusions with pedicle screws (PLFs) and posterior interbody fusion with pedicle screws (PLIFs). SUMMARY OF BACKGROUND DATA: Although radiographic nonunions in PLFs and PLIFs are well documented in the literature, there is no consensus on which technique has lower nonunions. Since some radiographic nonunions may be asymptomatic, a more clinically useful measure is operative nonunions, of which there is minimal research. METHODS: A retrospective cohort study, using data from the Kaiser Permanente Spine Registry, identified adult patients (≥18 years' old) who had elective single and multilevel PLFs and PLIFs. Descriptive statistics and 2-year incidence rates for operative nonunions were calculated by fusion-level (1-3), fusion type (PLF vs. PLIF), and levels fused (L3 to S1). Time-dependent multivariable Cox-Proportional Hazards regression was used to evaluate nonunion reoperation rates with adjustment for covariates. RESULTS: The cohort consisted of 3065 patients with PLFs (71.6%) and PLIFs (28.4%). Average age was 65.0 ±â€Š11.7, average follow-up time was 4.8 ±â€Š3.1 years, and average time to operative nonunion was 1.6 (±1.3) years. Single and multilevel incidence rates for nonunions after PLF versus PLIF were similar except for three-level fusions (2.9% [95% confidence interval, CI = 1.0-6.7] vs. 7.1% [95% CI = 0.2-33.9]). In adjusted models, there was no difference in risk of operative nonunions in PLIF compared to PLF (hazard ratio [HR]: 0.8, 95% CI = 0.4-1.6); however, patients with L5-S1 constructs with PLFs had 2.8 times the risk of operative nonunion compared to PLIFs (PLF: HR = 2.8, 95% CI = 1.3-6.2; PLIF: HR = 1.5, 95% CI = 0.4-5.1). CONCLUSION: In a large cohort of patients with >4 years of follow-up, we found no difference in operative nonunions between PLF and PLIF except for constructs that included L5-S1 in which the risk of nonunion was limited to PLF patients.Level of Evidence: 3.

Does the use of preoperative bisphosphonates in patients with osteopenia and osteoporosis affect lumbar fusion rates? Analysis from a national spine registry.

OBJECTIVE: Bisphosphonates are used to increase bone strength in treating osteopenia and osteoporosis, but their use for increasing lumbar fusion rates has been controversial. The objective of this study was to determine if preoperative treatment with bisphosphonates affects the reoperation rates for nonunions (operative nonunion rates) following lumbar fusions in patients with osteopenia or osteoporosis. METHODS: The authors conducted a cohort study using data from the Kaiser Permanente Spine Registry. Patients (aged ≥ 50 years) with a diagnosis of osteopenia or osteoporosis who underwent primary elective lumbar fusions for degenerative disc disease, deformity, or spondylolisthesis were included in the cohort. Repeated spinal procedures at the index lumbar levels were noted through chart review. Reoperations for symptomatic nonunions (operative nonunions), time to nonunion, and the nonunion spine level(s) were also identified. The crude 2-year cumulative incidence of operative nonunions was calculated as 1 minus the Kaplan-Meier estimator. Cox proportional hazard regression was used to evaluate the association between preoperative bisphosphonate use and operative nonunion after adjustment for covariates. Analysis was stratified by osteopenia and osteoporosis diagnosis. RESULTS: The cohort comprised 1040 primary elective lumbar fusion patients, 408 with osteopenia and 632 with osteoporosis. Ninety-seven (23.8%) patients with osteopenia and 370 (58.5%) patients with osteoporosis were preoperative bisphosphonate users. For the osteopenia group, no operative nonunions were observed in patients with preoperative bisphosphonate, while the crude 2-year incidence was 2.44% (95% CI 0.63-4.22) in the nonuser group. For the osteoporotic group, after adjustment for covariates, no difference was observed in risk for operative nonunions between the preoperative bisphosphonate users and nonusers (HR 0.96, 95% CI 0.20-4.55, p = 0.964). CONCLUSIONS: To the authors' knowledge, this study presents one of the largest series of patients with the diagnosis of osteopenia or osteoporosis in whom the effects of preoperative bisphosphonates on lumbar fusions were evaluated using operative nonunion rates as an outcome measure. The results indicate that preoperative bisphosphonate use had no effect on the operative nonunion rates for patients with osteoporosis. Similar indications were not confirmed in osteopenia patients because of the low nonunion frequency. Further studies are warranted to the determine if preoperative and postoperative timing of bisphosphonate use has any effect on lumbar fusion rates.

Occupation-related Cervical Spine Disease in Orthopaedic Surgeons.

INTRODUCTION: Musculoskeletal injury can substantially affect orthopaedic surgeons and productivity. The objective of this study was to assess occupation-related neck pain and cervical radiculopathy/myelopathy among orthopaedic surgeons and to identify the potential risk factors for injury. METHODS: An online survey was sent to orthopaedic surgeons via their state orthopaedic society. The survey consisted of items related to orthopaedic practices, such as the number of arthroscopic procedures done and the use of microscopes/loupes. The prevalence, potential causes, and reporting practices of neck pain and cervical radiculopathy/myelopathy among orthopaedic surgeons were also assessed. RESULTS: There were 685 responses from surgeons representing 27 states. A total of 59.3% of respondents reported neck pain and 22.8% reported cervical radiculopathy. After adjusting for age and sex, surgeons performing arthroscopy had an odds ratio of 3.3 (95% confidence interval: 1.4 to 8.3, P = 0.007) for neck pain. Only five of the surgeons with neck pain and one of the surgeons with cervical radiculopathy/myelopathy had ergonomic evaluations. CONCLUSION: Neck pain and cervical radiculopathy/myelopathy are common among orthopaedic surgeons. Associated factors included older age, higher stress levels, and performing arthroscopy. Cervical injuries are rarely reported, and ergonomic workplace evaluations are infrequent.

Cervical spine disease in surgeons performing arthroscopy or laparoscopy.

Minimal research exists regarding cervical spine disorders in surgeons who perform endoscopy. A confidential on-line survey regarding neck pain (NP), spine disease (SD), and radiculopathy/myelopathy (R/M) was sent to 722 surgeons from a managed, group-based health care system. 415 responded. 361 had endoscopy experience, of whom 24.4% had NP, 20.8% SD, and 3.9% R/M. Most respondents were less than 50 years of age (62.3%), and male (65.7%). Significant risk factors for NP included older age and female, whereas OB/Gyn specialty, increased age and job stress were for SD. After adjusting for age and gender, significant risk factors for NP and SD included greater surgeon experience. After also adjusting for job stress, significant risk factors for SD included increased surgeon experience and higher frequency of endoscopies. No association was found between use of digital OR. Endoscopy appears to place surgeons at higher risk of cervical disease. Level of Evidence: Level 3.

Cervical Spine Compensation in Adolescent Idiopathic Scoliosis.

STUDY DESIGN/SETTING: Cross-sectional. OBJECTIVES: To determine associations between cervical spine alignment and Lenke type for adolescent idiopathic scoliosis (AIS). SUMMARY OF BACKGROUND DATA: Although the lumbosacral spine and pelvis are standard considerations for evaluation of AIS, few studies have examined cervical spine alignment. These studies did not consider Lenke types upon which treatment decisions are based. METHODS: Stratified random sampling from 3,654 full-length preoperative lateral films of patients in a multicenter database of surgically treated AIS was done to obtain a representative sample from all Lenke types and thoracic curve modifiers. The C2-C7 sagittal Cobb and C2-C7 sagittal vertical axis (SVA) distances were measured by reviewers unaware of the patient's Lenke classification. C2-C7 sagittal Cobb and C2-C7 SVA among curve types and thoracic modifiers was compared using analysis of variance. RESULTS: There were 387 females and 84 males among patients in 471 randomly selected films; mean age at surgery was 14.8 ± 2.0 years. Significantly less cervical kyphosis was seen in Lenke 3 or 4 curves and greater cervical kyphosis in Lenke 1, 2, 5, and 6 curves. No significant differences in C2-C7 SVA were seen. CONCLUSIONS: Patients with AIS appear to compensate for abnormal thoracic sagittal alignment with changes in cervical sagittal alignment. This seems intuitive for Lenke 1 and 2 curves in which surgical restoration of thoracic kyphosis is a recognized goal and has been shown to improve cervical alignment. Cervical kyphosis was also noted in Lenke 5 and 6 curves, which suggests a need to consider compensatory thoracic and cervical sagittal alignment during surgical planning. Patients with Lenke 3 and 4 curves had more normal cervical alignment, which suggests that with the major portion of the curve located in the middle of the spine, there is more ability above and below to maintain a more normal sagittal alignment.

Correlation of weightbearing radiographs and stability of stress positive ankle fractures.

BACKGROUND: A positive external rotation stress test has been used as an indication for operative treatment of fractures of the lateral malleolus. The objective of the current study was to ascertain the results of a protocol initially treating stress positive ankle fractures nonoperatively and utilizing weightbearing radiographs in surgical decision making. METHODS: We performed a prospective study of lateral malleolar fractures with an associated medial ligamentous injury. All patients with fractures of the lateral malleolus with medial sided symptoms and/or signs, and an intact ankle mortise underwent an external rotation stress test to confirm injury to the deltoid ligament (stress positive). Patients with a positive stress test were placed in a short-leg walking cast and seen in 7 days where weightbearing radiographs of the ankle were obtained. If the radiographs demonstrated an intact mortise, then nonoperative treatment was continued. If the weightbearing radiographs demonstrated medial clear space widening, then the patient was offered operative treatment to restore the congruency of the ankle mortise. Patients were assessed for conversion to operative treatment, complications, and functional outcome. Thirty-eight patients were enrolled in the study. Using Lauge-Hansen classification 36 (95%) were stress positive supination-external rotation fractures and 2 (5%) were stress positive pronation-external rotation fractures. Followup assessment was performed at a minimum of 6 months and averaged 12 months. RESULTS: Weightbearing radiographs at the first post-injury clinic visit had an average medial clear space of 2.9 ±0.9 mm. Three (8%) patients met our criteria for medial clear space widening and underwent operative treatment. Of these three patients, two were pronation-external rotation fracture patterns. Therefore, 3% of the supination-external rotation IV fractures, and all of the pronation-external III/IV rotation fractures ultimately required operative treatment. At final followup, the average AOFAS hindfoot score was 92 ±8.1. CONCLUSION: Ligamentous supination-external rotation Stage IV fractures with an intact mortise on static radiographs can be initially treated nonoperatively. Weightbearing radiographs should be utilized to assess congruency of the ankle mortise during an early post-injury visit. Utilizing this approach, a significant number of surgeries were avoided, and good to excellent results were obtained. From our early experience, nonoperative treatment of pronation-external rotation III/IV injuries using this protocol is not recommended.