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The Bone & Joint Journal
Vol. 106-B, Issue 11 | Pages 1333 - 1341
1 Nov 2024
Cheung PWH Leung JHM Lee VWY Cheung JPY

Aims

Developmental cervical spinal stenosis (DcSS) is a well-known predisposing factor for degenerative cervical myelopathy (DCM) but there is a lack of consensus on its definition. This study aims to define DcSS based on MRI, and its multilevel characteristics, to assess the prevalence of DcSS in the general population, and to evaluate the presence of DcSS in the prediction of developing DCM.

Methods

This cross-sectional study analyzed MRI spine morphological parameters at C3 to C7 (including anteroposterior (AP) diameter of spinal canal, spinal cord, and vertebral body) from DCM patients (n = 95) and individuals recruited from the general population (n = 2,019). Level-specific median AP spinal canal diameter from DCM patients was used to screen for stenotic levels in the population-based cohort. An individual with multilevel (≥ 3 vertebral levels) AP canal diameter smaller than the DCM median values was considered as having DcSS. The most optimal cut-off canal diameter per level for DcSS was determined by receiver operating characteristic analyses, and multivariable logistic regression was performed for the prediction of developing DCM that required surgery.


The Bone & Joint Journal
Vol. 106-B, Issue 11 | Pages 1342 - 1347
1 Nov 2024
Onafowokan OO Jankowski PP Das A Lafage R Smith JS Shaffrey CI Lafage V Passias PG

Aims. The aim of this study was to investigate the impact of the level of upper instrumented vertebra (UIV) in frail patients undergoing surgery for adult spine deformity (ASD). Methods. Patients with adult spinal deformity who had undergone T9-to-pelvis fusion were stratified using the ASD-Modified Frailty Index into not frail, frail, and severely frail categories. ASD was defined as at least one of: scoliosis ≥ 20°, sagittal vertical axis (SVA) ≥ 5 cm, or pelvic tilt ≥ 25°. Means comparisons tests were used to assess differences between both groups. Logistic regression analyses were used to analyze associations between frailty categories, UIV, and outcomes. Results. A total of 477 patients were included (mean age 60.3 years (SD 14.9), mean BMI 27.5 kg/m. 2. (SD 5.8), mean Charlson Comorbidity Index (CCI) 1.67 (SD 1.66)). Overall, 74% of patients were female (n = 353), and 49.6% of patients were not frail (237), 35.4% frail (n = 169), and 15% severely frail (n = 71). At baseline, differences in age, BMI, CCI, and deformity were significant (all p = 0.001). Overall, 15.5% of patients (n = 74) had experienced mechanical complications by two years (8.1% not frail (n = 36), 15.1% frail (n = 26), and 16.3% severely frail (n = 12); p = 0.013). Reoperations also differed between groups (20.2% (n = 48) vs 23.3% (n = 39) vs 32.6% (n = 23); p = 0.011). Controlling for osteoporosis, baseline deformity, and degree of correction (by sagittal age-adjusted score (SAAS) matching), frail and severely frail patients were more likely to experience mechanical complications if they had heart failure (odds ratio (OR) 6.6 (95% CI 1.6 to 26.7); p = 0.008), depression (OR 5.1 (95% CI 1.1 to 25.7); p = 0.048), or cancer (OR 1.5 (95% CI 1.1 to 1.4); p = 0.004). Frail and severely frail patients experienced higher rates of mechanical complication than ‘not frail’ patients at two years (19% (n = 45) vs 11.9% (n = 29); p = 0.003). When controlling for baseline deformity and degree of correction in severely frail and frail patients, severely frail patients were less likely to experience clinically relevant proximal junctional kyphosis or failure or mechanical complications by two years, if they had a more proximal UIV. Conclusion. Frail patients are at risk of a poor outcome after surgery for adult spinal deformity due to their comorbidities. Although a definitively prescriptive upper instrumented vertebra remains elusive, these patients appear to be at greater risk for a poor outcome if the upper instrumented vertebra is sited more distally. Cite this article: Bone Joint J 2024;106-B(11):1342–1347


The Bone & Joint Journal
Vol. 106-B, Issue 10 | Pages 1176 - 1181
1 Oct 2024
Helenius L Gerdhem P Ahonen M Syvänen J Jalkanen J Nietosvaara Y Helenius I

Aims. Closed suction subfascial drainage is widely used after instrumented posterior spinal fusion in patients with a spinal deformity. The aim of this study was to determine the effect of this wound drainage on the outcomes in patients with adolescent idiopathic scoliosis (AIS). This was a further analysis of a randomized, multicentre clinical trial reporting on patients after posterior spinal fusion using segmental pedicle screw instrumentation. In this study the incidence of deep surgical site infection (SSI) and chronic postoperative pain at two years’ follow-up are reported. Methods. We conducted a randomized, multicentre clinical trial on adolescents undergoing posterior spinal fusion for AIS using segmental pedicle screw instrumentation. A total of 90 consecutive patients were randomized into a ‘drain’ or ‘no drain’ group at the time of wound closure, using the sealed envelope technique (1:1). The primary outcomes in the initial study were the change in the level of haemoglobin in the blood postoperatively and total blood loss. A secondary outcome was the opioid consumption immediately after surgery. The aim of this further study was to report the rate of deep SSI and persistent postoperative pain, at two years' follow-up. Results. As previously reported, the mean 48-hour opioid consumption was significantly higher in the no drain group (2.0 mg/kg (SD 0.8) vs 1.4 mg/kg (SD 0.7); p = 0.005). There were no delayed deep SSIs. At two years’ follow-up, the mean Scoliosis Research Society 24-item questionnaire (SRS-24) total score did not differ between the groups (4.11 (SD 0.47) vs 4.16 (SD 0.33); p = 0.910). The mean SRS-24 pain score was 4.28 (SD 0.48) in the no drain group compared with 4.33 (SD 0.66) in the drain group (p = 0.245). Seven patients (19%) in the no drain group and six in the drain group (14%) reported moderate to severe pain (numerical rating scale ≥ 4) at two years’ follow-up (p = 0.484). The general self-image domain score was significantly higher in the no drain group compared with the drain group (4.02 (SD 0.74) vs 4.59 (SD 0.54); p < 0.001). Conclusion. The main finding in this study was that more severe pain immediately after surgery did not result in a higher incidence of chronic pain in the no drain group compared with the drain group. Back pain and health-related quality of life at two years’ follow-up did not differ between the groups. The patient-reported self-image domain was significantly better in the no drain group compared with the drain group. Cite this article: Bone Joint J 2024;106-B(10):1176–1181


The Bone & Joint Journal
Vol. 106-B, Issue 6 | Pages 596 - 602
1 Jun 2024
Saarinen AJ Sponseller P Thompson GH White KK Emans J Cahill PJ Hwang S Helenius I

Aims

The aim of this study was to compare outcomes after growth-friendly treatment for early-onset scoliosis (EOS) between patients with skeletal dysplasias versus those with other syndromes.

Methods

We retrospectively identified 20 patients with skeletal dysplasias and 292 with other syndromes (control group) who had completed surgical growth-friendly EOS treatment between 1 January 2000 and 31 December 2018. We compared radiological parameters, complications, and health-related quality of life (HRQoL) at mean follow-up of 8.6 years (SD 3.3) in the dysplasia group and 6.6 years (SD 2.6) in the control group.


Bone & Joint Open
Vol. 5, Issue 3 | Pages 243 - 251
25 Mar 2024
Wan HS Wong DLL To CS Meng N Zhang T Cheung JPY

Aims

This systematic review aims to identify 3D predictors derived from biplanar reconstruction, and to describe current methods for improving curve prediction in patients with mild adolescent idiopathic scoliosis.

Methods

A comprehensive search was conducted by three independent investigators on MEDLINE, PubMed, Web of Science, and Cochrane Library. Search terms included “adolescent idiopathic scoliosis”,“3D”, and “progression”. The inclusion and exclusion criteria were carefully defined to include clinical studies. Risk of bias was assessed with the Quality in Prognostic Studies tool (QUIPS) and Appraisal tool for Cross-Sectional Studies (AXIS), and level of evidence for each predictor was rated with the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) approach. In all, 915 publications were identified, with 377 articles subjected to full-text screening; overall, 31 articles were included.


The Bone & Joint Journal
Vol. 106-B, Issue 3 | Pages 286 - 292
1 Mar 2024
Tang S Cheung JPY Cheung PWH

Aims

To systematically evaluate whether bracing can effectively achieve curve regression in patients with adolescent idiopathic scoliosis (AIS), and to identify any predictors of curve regression after bracing.

Methods

Two independent reviewers performed a comprehensive literature search in PubMed, Ovid, Web of Science, Scopus, and Cochrane Library to obtain all published information about the effectiveness of bracing in achieving curve regression in AIS patients. Search terms included “brace treatment” or “bracing,” “idiopathic scoliosis,” and “curve regression” or “curve reduction.” Inclusion criteria were studies recruiting patients with AIS undergoing brace treatment and one of the study outcomes must be curve regression or reduction, defined as > 5° reduction in coronal Cobb angle of a major curve upon bracing completion. Exclusion criteria were studies including non-AIS patients, studies not reporting p-value or confidence interval, animal studies, case reports, case series, and systematic reviews. The GRADE approach to assessing quality of evidence was used to evaluate each publication.


The Bone & Joint Journal
Vol. 106-B, Issue 1 | Pages 53 - 61
1 Jan 2024
Buckland AJ Huynh NV Menezes CM Cheng I Kwon B Protopsaltis T Braly BA Thomas JA

Aims

The aim of this study was to reassess the rate of neurological, psoas-related, and abdominal complications associated with L4-L5 lateral lumbar interbody fusion (LLIF) undertaken using a standardized preoperative assessment and surgical technique.

Methods

This was a multicentre retrospective study involving consecutively enrolled patients who underwent L4-L5 LLIF by seven surgeons at seven institutions in three countries over a five-year period. The demographic details of the patients and the details of the surgery, reoperations and complications, including femoral and non-femoral neuropraxia, thigh pain, weakness of hip flexion, and abdominal complications, were analyzed. Neurological and psoas-related complications attributed to LLIF or posterior instrumentation and persistent symptoms were recorded at one year postoperatively.


Bone & Joint Open
Vol. 4, Issue 8 | Pages 573 - 579
8 Aug 2023
Beresford-Cleary NJA Silman A Thakar C Gardner A Harding I Cooper C Cook J Rothenfluh DA

Aims

Symptomatic spinal stenosis is a very common problem, and decompression surgery has been shown to be superior to nonoperative treatment in selected patient groups. However, performing an instrumented fusion in addition to decompression may avoid revision and improve outcomes. The aim of the SpInOuT feasibility study was to establish whether a definitive randomized controlled trial (RCT) that accounted for the spectrum of pathology contributing to spinal stenosis, including pelvic incidence-lumbar lordosis (PI-LL) mismatch and mobile spondylolisthesis, could be conducted.

Methods

As part of the SpInOuT-F study, a pilot randomized trial was carried out across five NHS hospitals. Patients were randomized to either spinal decompression alone or spinal decompression plus instrumented fusion. Patient-reported outcome measures were collected at baseline and three months. The intended sample size was 60 patients.


Bone & Joint Research
Vol. 12, Issue 4 | Pages 245 - 255
3 Apr 2023
Ryu S So J Ha Y Kuh S Chin D Kim K Cho Y Kim K

Aims. To determine the major risk factors for unplanned reoperations (UROs) following corrective surgery for adult spinal deformity (ASD) and their interactions, using machine learning-based prediction algorithms and game theory. Methods. Patients who underwent surgery for ASD, with a minimum of two-year follow-up, were retrospectively reviewed. In total, 210 patients were included and randomly allocated into training (70% of the sample size) and test (the remaining 30%) sets to develop the machine learning algorithm. Risk factors were included in the analysis, along with clinical characteristics and parameters acquired through diagnostic radiology. Results. Overall, 152 patients without and 58 with a history of surgical revision following surgery for ASD were observed; the mean age was 68.9 years (SD 8.7) and 66.9 years (SD 6.6), respectively. On implementing a random forest model, the classification of URO events resulted in a balanced accuracy of 86.8%. Among machine learning-extracted risk factors, URO, proximal junction failure (PJF), and postoperative distance from the posterosuperior corner of C7 and the vertical axis from the centroid of C2 (SVA) were significant upon Kaplan-Meier survival analysis. Conclusion. The major risk factors for URO following surgery for ASD, i.e. postoperative SVA and PJF, and their interactions were identified using a machine learning algorithm and game theory. Clinical benefits will depend on patient risk profiles. Cite this article: Bone Joint Res 2023;12(4):245–255


The Bone & Joint Journal
Vol. 105-B, Issue 4 | Pages 431 - 438
15 Mar 2023
Vendeuvre T Tabard-Fougère A Armand S Dayer R

Aims

This study aimed to evaluate rasterstereography of the spine as a diagnostic test for adolescent idiopathic soliosis (AIS), and to compare its results with those obtained using a scoliometer.

Methods

Adolescents suspected of AIS and scheduled for radiographs were included. Rasterstereographic scoliosis angle (SA), maximal vertebral surface rotation (ROT), and angle of trunk rotation (ATR) with a scoliometer were evaluated. The area under the curve (AUC) from receiver operating characteristic (ROC) plots were used to describe the discriminative ability of the SA, ROT, and ATR for scoliosis, defined as a Cobb angle > 10°. Test characteristics (sensitivity and specificity) were reported for the best threshold identified using the Youden method. AUC of SA, ATR, and ROT were compared using the bootstrap test for two correlated ROC curves method.


The Bone & Joint Journal
Vol. 105-B, Issue 4 | Pages 439 - 448
15 Mar 2023
Hong H Pan X Song J Fang N Yang R Xiang L Wang X Huang C

Aims

The prevalence of scoliosis is not known in patients with idiopathic short stature, and the impact of treatment with recombinant human growth hormone on those with scoliosis remains controversial. We investigated the prevalence of scoliosis radiologically in children with idiopathic short stature, and the impact of treatment with growth hormone in a cross-sectional and retrospective cohort study.

Methods

A total of 2,053 children with idiopathic short stature and 4,106 age- and sex-matched (1:2) children without short stature with available whole-spine radiographs were enrolled in the cross-sectional study. Among them, 1,056 with idiopathic short stature and 790 controls who had radiographs more than twice were recruited to assess the development and progression of scoliosis, and the need for bracing and surgery.


The Bone & Joint Journal
Vol. 105-B, Issue 2 | Pages 166 - 171
1 Feb 2023
Ragborg LC Dragsted C Ohrt-Nissen S Andersen T Gehrchen M Dahl B

Aims

Only a few studies have investigated the long-term health-related quality of life (HRQoL) in patients with an idiopathic scoliosis. The aim of this study was to investigate the overall HRQoL and employment status of patients with an idiopathic scoliosis 40 years after diagnosis, to compare it with that of the normal population, and to identify possible predictors for a better long-term HRQoL.

Methods

We reviewed the full medical records and radiological reports of patients referred to our hospital with a scoliosis of childhood between April 1972 and April 1982. Of 129 eligible patients with a juvenile or adolescent idiopathic scoliosis, 91 took part in the study (71%). They were evaluated with full-spine radiographs and HRQoL questionnaires and compared with normative data. We compared the HRQoL between observation (n = 27), bracing (n = 46), and surgical treatment (n = 18), and between thoracic and thoracolumbar/lumbar (TL/L) curves.


The Bone & Joint Journal
Vol. 104-B, Issue 11 | Pages 1249 - 1255
1 Nov 2022
Williamson TK Passfall L Ihejirika-Lomedico R Espinosa A Owusu-Sarpong S Lanre-Amos T Schoenfeld AJ Passias PG

Aims. Postoperative complication rates remain relatively high after adult spinal deformity (ASD) surgery. The extent to which modifiable patient-related factors influence complication rates in patients with ASD has not been effectively evaluated. The aim of this retrospective cohort study was to evaluate the association between modifiable patient-related factors and complications after corrective surgery for ASD. Methods. ASD patients with two-year data were included. Complications were categorized as follows: any complication, major, medical, surgical, major mechanical, major radiological, and reoperation. Modifiable risk factors included smoking, obesity, osteoporosis, alcohol use, depression, psychiatric diagnosis, and hypertension. Patients were stratified by the degree of baseline deformity (low degree of deformity (LowDef)/high degree of deformity (HighDef): below or above 20°) and age (Older/Younger: above or below 65 years). Complication rates were compared for modifiable risk factors in each age/deformity group, using multivariable logistic regression analysis to adjust for confounders. Results. A total of 480 ASD patients met the inclusion criteria. By two years, complication rates were 72% ≥ one complication, 28% major, 21% medical, 27% surgical, 11% major radiological, 8% major mechanical, and 22% required reoperation. Younger LowDef patients with osteoporosis were more likely to suffer either a major mechanical (odds ratio (OR) 5.9 (95% confidence interval (CI) 1.1 to 36.9); p = 0.048) or radiological complication (OR 7.0 (95% CI 1.9 to 25.9); p = 0.003). Younger HighDef patients were much more likely to develop complications if obese, especially major mechanical complications (OR 2.8 (95% CI 1.1 to 8.6); p = 0.044). Older HighDef patients developed more complications when diagnosed with depression, including major radiological complications (OR 3.5 (95% CI 1.1 to 10.6); p = 0.033). Overall, a diagnosis of depression proved to be a risk factor for the development of major radiological complications (OR 2.4 (95% CI 1.3 to 4.5); p = 0.005). Conclusion. Certain modifiable patient-related factors, especially osteoporosis, obesity, and mental health status, are associated with an increased risk of complications after surgery for spinal deformity. Surgeons should look for these conditions when assessing a patient for surgery, and optimize them to the fullest extent possible before proceeding to surgical correction so as to minimize the prospect of postoperative morbidity. Cite this article: Bone Joint J 2022;104-B(11):1249–1255


The Bone & Joint Journal
Vol. 104-B, Issue 9 | Pages 1067 - 1072
1 Sep 2022
Helenius L Gerdhem P Ahonen M Syvänen J Jalkanen J Charalampidis A Nietosvaara Y Helenius I

Aims

The aim of this study was to evaluate whether, after correction of an adolescent idiopathic scoliosis (AIS), leaving out the subfascial drain gives results that are no worse than using a drain in terms of total blood loss, drop in haemoglobin level, and opioid consumption.

Methods

Adolescents (aged between 10 and 21 years) with an idiopathic scoliosis (major curve ≥ 45°) were eligible for inclusion in this randomized controlled noninferiority trial (n = 125). A total of 90 adolescents who had undergone segmental pedicle screw instrumentation were randomized into no-drain or drain groups at the time of wound closure using the sealed envelope technique (1:1). The primary outcome was a drop in the haemoglobin level during first three postoperative days. Secondary outcomes were 48-hour postoperative oxycodone consumption and surgical complications.


Aims

Psychoeducative prehabilitation to optimize surgical outcomes is relatively novel in spinal fusion surgery and, like most rehabilitation treatments, they are rarely well specified. Spinal fusion patients experience anxieties perioperatively about pain and immobility, which might prolong hospital length of stay (LOS). The aim of this prospective cohort study was to determine if a Preoperative Spinal Education (POSE) programme, specified using the Rehabilitation Treatment Specification System (RTSS) and designed to normalize expectations and reduce anxieties, was safe and reduced LOS.

Methods

POSE was offered to 150 prospective patients over ten months (December 2018 to November 2019) Some chose to attend (Attend-POSE) and some did not attend (DNA-POSE). A third independent retrospective group of 150 patients (mean age 57.9 years (SD 14.8), 50.6% female) received surgery prior to POSE (pre-POSE). POSE consisted of an in-person 60-minute education with accompanying literature, specified using the RTSS as psychoeducative treatment components designed to optimize cognitive/affective representations of thoughts/feelings, and normalize anxieties about surgery and its aftermath. Across-group age, sex, median LOS, perioperative complications, and readmission rates were assessed using appropriate statistical tests.


The Bone & Joint Journal
Vol. 104-B, Issue 2 | Pages 257 - 264
1 Feb 2022
Tahir M Mehta D Sandhu C Jones M Gardner A Mehta JS

Aims

The aim of this study was to compare the clinical and radiological outcomes of patients with early-onset scoliosis (EOS), who had undergone spinal fusion after distraction-based spinal growth modulation using either traditional growing rods (TGRs) or magnetically controlled growing rods (MCGRs).

Methods

We undertook a retrospective review of skeletally mature patients who had undergone fusion for an EOS, which had been previously treated using either TGRs or MCGRs. Measured outcomes included sequential coronal T1 to S1 height and major curve (Cobb) angle on plain radiographs and any complications requiring unplanned surgery before final fusion.


The Bone & Joint Journal
Vol. 104-B, Issue 2 | Pages 265 - 273
1 Feb 2022
Mens RH Bisseling P de Kleuver M van Hooff ML

Aims

To determine the value of scoliosis surgery, it is necessary to evaluate outcomes in domains that matter to patients. Since randomized trials on adolescent idiopathic scoliosis (AIS) are scarce, prospective cohort studies with comparable outcome measures are important. To enhance comparison, a core set of patient-related outcome measures is available. The aim of this study was to evaluate the outcomes of AIS fusion surgery at two-year follow-up using the core outcomes set.

Methods

AIS patients were systematically enrolled in an institutional registry. In all, 144 AIS patients aged ≤ 25 years undergoing primary surgery (median age 15 years (interquartile range 14 to 17) were included. Patient-reported (condition-specific and health-related quality of life (QoL); functional status; back and leg pain intensity) and clinician-reported outcomes (complications, revision surgery) were recorded. Changes in patient-reported outcome measures (PROMs) were analyzed using Friedman’s analysis of variance. Clinical relevancy was determined using minimally important changes (Scoliosis Research Society (SRS)-22r), cut-off values for relevant effect on functioning (pain scores) and a patient-acceptable symptom state (PASS; Oswestry Disability Index).


The Bone & Joint Journal
Vol. 104-B, Issue 1 | Pages 103 - 111
1 Jan 2022
Li J Hu Z Qian Z Tang Z Qiu Y Zhu Z Liu Z

Aims

The outcome following the development of neurological complications after corrective surgery for scoliosis varies from full recovery to a permanent deficit. This study aimed to assess the prognosis and recovery of major neurological deficits in these patients, and to determine the risk factors for non-recovery, at a minimum follow-up of two years.

Methods

A major neurological deficit was identified in 65 of 8,870 patients who underwent corrective surgery for scoliosis, including eight with complete paraplegia and 57 with incomplete paraplegia. There were 23 male and 42 female patients. Their mean age was 25.0 years (SD 16.3). The aetiology of the scoliosis was idiopathic (n = 6), congenital (n = 23), neuromuscular (n = 11), neurofibromatosis type 1 (n = 6), and others (n = 19). Neurological function was determined by the American Spinal Injury Association (ASIA) impairment scale at a mean follow-up of 45.4 months (SD 17.2). the patients were divided into those with recovery and those with no recovery according to the ASIA scale during follow-up.


The Bone & Joint Journal
Vol. 104-B, Issue 1 | Pages 120 - 126
1 Jan 2022
Kafle G Garg B Mehta N Sharma R Singh U Kandasamy D Das P Chowdhury B

Aims

The aims of this study were to determine the diagnostic yield of image-guided biopsy in providing a final diagnosis in patients with suspected infectious spondylodiscitis, to report the diagnostic accuracy of various microbiological tests and histological examinations in these patients, and to report the epidemiology of infectious spondylodiscitis from a country where tuberculosis (TB) is endemic, including the incidence of drug-resistant TB.

Methods

A total of 284 patients with clinically and radiologically suspected infectious spondylodiscitis were prospectively recruited into the study. Image-guided biopsy of the vertebral lesion was performed and specimens were sent for various microbiological tests and histological examinations. The final diagnosis was determined using a composite reference standard based on clinical, radiological, serological, microbiological, and histological findings. The overall diagnostic yield of the biopsy, and that for each test, was calculated in light of the final diagnosis.


Bone & Joint Open
Vol. 2, Issue 12 | Pages 1096 - 1101
23 Dec 2021
Mohammed R Shah P Durst A Mathai NJ Budu A Woodfield J Marjoram T Sewell M

Aims

With resumption of elective spine surgery services in the UK following the first wave of the COVID-19 pandemic, we conducted a multicentre British Association of Spine Surgeons (BASS) collaborative study to examine the complications and deaths due to COVID-19 at the recovery phase of the pandemic. The aim was to analyze the safety of elective spinal surgery during the pandemic.

Methods

A prospective observational study was conducted from eight spinal centres for the first month of operating following restoration of elective spine surgery in each individual unit. Primary outcome measure was the 30-day postoperative COVID-19 infection rate. Secondary outcomes analyzed were the 30-day mortality rate, surgical adverse events, medical complications, and length of inpatient stay.