Complications in endoscopic spine surgery: a systematic review.

PURPOSE: This systematic review aims to investigate the complication rate of endoscopic spine surgeries, stratifying them by technique, district and kind of procedure performed. METHODS: This study was conducted according to the PRISMA statement. The literature search was conducted in MEDLINE, CINAHL, EMBASE, Cochrane Register, OTseeker and ScienceDirect database. Types of studies included were observational studies (cohort studies, case-control studies and case series) and randomised or quasi-randomised clinical with human subjects. No restrictions on publication year were applied. Repeated articles, reviews, expert's comments, congress abstracts, technical notes and articles not in English were excluded. Several data were extracted from the articles. In particular, data of perioperative (≤ 3 months) and late (> 3 months) complications were collected and grouped according to: (1) surgical technique [uniportal full-endoscopic spine surgery (UESS) or unilateral biportal endoscopic spine surgery (UBESS)]; (2) spinal district treated [cervical, thoracic or lumbar] and (3) type of procedure [discectomy/decompression or fusion]. Complication analysis was performed in subgroups with at least 100 patients to have clinically meaningful statistical validity. RESULTS: A total of 117 full-text articles were assessed for eligibility. Of the 117 records included, 95 focused their research on UESS (14 LOE V, 33 LOE IV, 43 LOE III and five LOE II) and 23 on UBESS (three LOE V, eight LOE IV, 10 LOE III and two LOE II). A total of 20,020 patients were extracted to investigate the incidence of different perioperative and late complications, 10,405 for UESS and 9615 for UBESS. CONCLUSION: The present study summarises the complications reported in the literature for spinal endoscopic procedures. On the one hand, the most relevant described were perioperative complications (transient neurological deficit, dural tear and dysesthesia) that are especially meaningful for endoscopic discectomy and decompression. On the other hand, late complications, such as mechanical implant failure, are more common in endoscopic interbody fusion. LEVEL OF EVIDENCE: I.

Gait function assessed using 3D gait analysis in patients with cervical spinal myelopathy before and after surgical decompression: a systematic review and meta-analysis.

BACKGROUND: Degenerative cervical myelopathy (DCM) is the most common cause of cervical spinal cord dysfunction in adults and the result of chronic degenerative changes of the cervical spine. The compression of the spinal cord can lead to ischemia, inflammation, and neuronal apoptosis with a consequent impairment of the neurological function. Gait impairment is one of the most frequent signs of DCM. PURPOSE: To investigate the changes in spatio-temporal gait parameters assessed using 3D gait analysis in patients affected by DCM compared with healthy controls and the effect of surgical decompression on these parameters. STUDY DESIGN/SETTING: Systematic review and meta-analysis. PATIENT SAMPLE: The meta-analysis included 267 patients with DCM and 276 healthy controls. OUTCOME MEASURES: Spatio-temporal parameters of gait were assessed. The primary outcome was gait speed; the secondary outcomes were cadence, stride length, step width, stride time, single-limb support time, and double-limb support time. METHODS: Studies reporting spatial and/or temporal gait parameters measured using 3D gait analysis in patients with DCM were included. Data sources were Embase, Medline, and the Core Collection of Web of Science. Meta-analyses were performed to investigate the influence of surgical decompression in patients measured before and after surgery as well as to compare gait parameters of patients with DCM with controls. RESULTS: Thirteen studies reporting on 267 patients with DCM and 276 healthy controls met the inclusion criteria. Seven studies compared patients with DCM with healthy controls, three studies compared gait in patients with DCM before and after surgical decompression, and three studies performed both comparisons. Compared with healthy controls, patients with DCM had slower gait speed (Standardized Mean Difference (SMD), -1.49; 95% confidence interval (CI) [-1.86; -1.13]; p<.001), lower cadence (SMD, -0.78; 95%CI [-1.00; -0.56]; p<.001), shorter stride length (SMD, -1.27; 95%CI [-1.53, -1.01]; p<.001), greater step width (SMD, 0.98; 95%CI [0.42, 1.54]; p=.003), longer stride time (SMD, 0.77; 95%CI [0.37, 1.16]; p=.009), single-limb support phase (SMD, -0.68; 95%CI [-1.06; -0.29]; p=.011), and double-limb support phase (SMD 0.84; 95%CI [0.35, 1.32]; p=.012). After surgical decompression, patients with DCM showed an improvement in gait speed (SMD, 0.57 (95%CI [0.29; 0.85]; p=.003) and no significant differences in other spatio-temporal parameters. CONCLUSIONS: Patients with DCM have clearly different spatio-temporal gait parameters than healthy controls. Gait speed is the only spatio-temporal gait parameter that improves significantly after surgical decompression suggesting that gait speed may be an important clinical outcome parameter in patients with DCM.

The influence of peri-operative depressive symptoms on medium-term spine surgery outcome: a prospective study.

PURPOSE: To investigate the role of depressive symptoms on clinical outcomes in patients undergoing spinal surgery up to 2-year follow-up. METHODS: The study used data from an institutional spine surgery registry (January 2016, through March 2022) to identify patients (> 18 years) undergoing spine surgery. Patients with Oswestry Disability Index (ODI) < 20/100 at baseline or undergoing surgery on the cervical spine or for idiopathic spinal deformity and trauma patients were excluded. The patients were divided into two groups based on the pre-operative Mental Component Summary (MCS) score of the SF-36: depression group (MCS ≤ 35) or non-depression group (MCS > 35). The ODI and MCS scores trajectory were wined over the 24-month post-surgery between groups. Additionally, a secondary subgroup analysis was conducted comparing outcomes between those with depressive symptoms (persistent-depression subgroup) and those without depressive symptoms (never-depression subgroup) at 3 months after surgery. RESULTS: A total of 2164 patients who underwent spine surgery were included. The pre-operative depression group reported higher ODI total scores and lower MCS than the pre-operative non-depression group at all time points (P < 0.001). The persistent-depression subgroup reported higher ODI total scores and lower MCS than the never-depression subgroup at all follow-ups (P < 0.001). CONCLUSION: Functional disability and mental health status improve in patients with depression symptoms undergoing spinal surgery. Despite this improvement, they do not reach the values of non-depressed subjects. Over the 2-year follow-up time, patients with depression show a different trajectory of ODI and MCS. Caregivers should be aware of these results to counsel patients with depression symptoms.

Kinematics and paraspinal muscle activation patterns during walking differ between patients with lumbar spinal stenosis and controls.

BACKGROUND: The narrowing of the spinal canal due to degenerative processes may lead to symptomatic lumbar spinal stenosis (sLSS) and impairments in the patients' gait. Changes in lower extremity joint kinematics and trunk flexion angles have been reported, yet less is known about muscle activation patterns of paraspinal and gluteal muscles in patients with sLSS compared to healthy participants. RESEARCH QUESTION: Do muscle activation patterns together with sagittal joint kinematics differ between patients with sLSS and healthy controls and do these differences-quantified using gait scores-correlate with clinical scores? METHODS: In 20 patients with sLSS scheduled for surgery and 19 healthy participants, gait was assessed using seven inertial sensors and muscle activation of gluteus medius, erector spinae and multifidus using wireless surface electromyography (EMG). Differences in joint kinematics and EMG patterns were assessed using statistical parametric mapping with non-parametric independent sample t tests (P < 0.05). Gait scores that describe the overall deviation in joint angles (mGPS) and muscle activation patterns (EMG-Profile Score) were calculated as root mean square distances between patients and healthy participants and their associations with clinical scores (pain, Oswestry Disability Score (ODI)) were analyzed using Spearman's correlation coefficients rho (P < 0.05). RESULTS: Patients had larger mGPS (+1.9°) and EMG-Profile Scores (+50%) and walked on average slower (-0.26 m/s) than controls. EMG patterns revealed higher activation of multifidus, erector spinae and gluteus medius during midstance in patients compared to controls. Clinical scores (pain, ODI) did not correlate with mGPS or EMG-Profile Scores within patients. SIGNIFICANCE: Observed differences in gait and muscle activation patterns and in the summary scores of gait and EMG deviations between patients with sLSS and healthy controls may represent additional functional outcomes reflecting the functional status of patients that can be measured using wearable sensors and hence is suitable for application in clinical practice.

Radiographic study of peak velocity of pelvic incidence in adolescent idiopathic scoliosis.

BACKGROUND: Pelvic incidence (PI), a parameter related to the ideal spinopelvic alignment, is a morphological parameter that is usually considered fixed, but the PI's growth during adolescence has been reported. We investigated the peak PI velocity during adolescence and describe the relationship between increasing PI and changes in the morphology of the pelvis and sacrum. METHODS: We measured standing height (SH) and radiological anatomical parameters including pelvic height (PH), pelvic width (PW), sacral width (SW), femoral head-sacrum (FH-S), sacrum-coccyx (S-C) length, and S-C distance at each follow-up of 76 adolescent idiopathic scoliosis (AIS) patients. ΔParameter was the difference between the next measurement and the previous one. Growth velocity was ΔParameter divided by time interval. All ΔParameters were compared between different Risser stages using repeated-measures analysis of variance (ANOVA). The Pearson coefficients of correlation were calculated to assess the relationships between PI and ΔParameters. RESULTS: PI reached peak growth with a 1.6°/year growth in females and 1.8°/year in males at Risser stage 1. PI tended to grow rapidly with Risser 0 and closed triradiate cartilage (female: 1.3°/year and male: 1.4°/year) and to slow down at Risser 2 (female: 1.2°/year and male: 1.3°/year). ΔPI strongly correlated with ΔFH-S (R>0.508, P<0.05) and also correlated with ΔSH, ΔPH, ΔPW, ΔSW, and ΔS-C length (R>0.192, P<0.05) but not correlated with ΔS-C distance and ΔS-C ratio. CONCLUSIONS: In patients with AIS, the peak PI velocity is at Risser 1, and it is still increasing at Risser 5. Our result suggested that the growth of the PI may be associated with SH and changing pelvic morphology during skeletal growth of adolescence.

Assessing Fatty Infiltration of Paraspinal Muscles in Patients With Lumbar Spinal Stenosis: Goutallier Classification and Quantitative MRI Measurements.

Objective: Fatty infiltration of paraspinal muscle is associated with spinal disorders. It can be assessed qualitatively (i.e., Goutallier classification) and quantitatively using image processing software. The aims of this study were to compare paraspinal muscle fatty infiltration as assessed using the Goutallier classification vs. quantitative magnetic resonance images (MRI) measurements and to investigate the association between anthropometric parameters and paraspinal muscle morphology and fatty infiltration in patients with symptomatic lumbar spinal stenosis (LSS). Methods: Patients affected by symptomatic LSS scheduled for surgery with available MRI of the lumbar spine were included in this retrospective cross-sectional study. Fatty infiltration at each lumbar level was rated qualitatively according to the Goutallier classification and quantified based on the cross-sectional area (CSA) of the paraspinal muscle, of its lean fraction (LeanCSA), and the ratio between LeanCSA and CSA and the CSA relative to the CSA of vertebral body (RCSA). Considering the muscle as a single unit, overall fatty infiltration according to Goutallier, overall CSA, LeanCSA, LeanCSA/CSA, and RCSA were computed as averages (aGoutallier, aCSA, aLeanCSA, aLeanCSA/aCSA, and aRCSA). Associations among parameters were assessed using Spearman's respective Pearson's correlation coefficients. Results: Eighteen patients, with a mean age of 71.3 years, were included. aGoutallier correlated strongly with aLeanCSA and aLeanCSA/aCSA (R = -0.673 and R = -0.754, both P < 0.001). There was a very strong correlation between values of the left and right sides for CSA (R = 0.956, P < 0.001), LeanCSA (R = 0.900, P < 0.001), and LeanCSA/CSA (R = 0.827, P < 0.001) at all levels. Among all anthropometric measurements, paraspinal muscle CSA correlated the most with height (left: R = 0.737, P < 0.001; right: R = 0.700, P < 0.001), while there was a moderate correlation between vertebral body CSA and paraspinal muscle CSA (left: R = 0.448, P < 0.001; right: R = 0.454, P < 0.001). Paraspinal muscle CSA correlated moderately with body mass index (BMI; left: R = 0.423, P < 0.001; right: R = 0.436, P < 0.001), and there was no significant correlation between aLeanCSA or aLeanCSA/CSA and BMI. Conclusions: The Goutallier classification is a reliable yet efficient tool for assessing fatty infiltration of paraspinal muscles in patients with symptomatic LSS. We suggest taking body height as a reference for normalization in future studies assessing paraspinal muscle atrophy and fatty infiltration.

Association between fatty infiltration of paraspinal muscle, sagittal spinopelvic alignment and stenosis grade in patients with degenerative lumbar spinal stenosis.

INTRODUCTION: Sagittal balance and fatty infiltration of paraspinal muscle are important factors in patients with lumbar spinal stenosis (LSS) that may affect patients' quality of life. Sagittal spinopelvic parameters and fatty infiltration may be associated with the severity of LSS. The purpose of this study was to test the hypothesis that severity of fatty infiltration correlates with severity of LSS and with sagittal pelvic alignment independent of age. METHODS: Age and body mass index (BMI) were extracted. Fatty infiltration was rated according to Goutallier classification and the severity of LSS was graded according to Schizas at five intervertebral disc levels. Overall fatty infiltration was computed as average fatty infiltration (aFI) and severity of LSS was defined as the highest severity of LSS of all segments. The sagittal spinopelvic parameters pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), lumbar lordosis (LL) and PI-LL were measured. Associations among parameters were assessed using Spearman correlation coefficients adjusted for age (α = 0.05). RESULTS: 165 LSS patients with a median age of 69 years were included. All parameters correlated with age (R>0.162, P<0.05) except BMI and LL (R<0.007, P>0.05). aFI correlated with PI, PT and PI-LL before (R>0.371, P<0.05) and after (R>0.180, P<0.05) adjusting for age. Severity of LSS correlated with PI, PT and PI-LL before (R>0.187, P<0.05) but not after (R<0.130, P>0.05) adjusting for age. aFI correlated with severity of LSS before (R=0.349, P<0.05) but not (R=0.114, P>0.05) after adjusting for age. CONCLUSIONS: The correlation of aFI with sagittal spinopelvic parameters indicates that there might be a relationship between muscle characteristics and the sagittal alignment. Sagittal spinopelvic parameters and fatty infiltration of paraspinal muscles are not associated with radiological severity of LSS. Whether they are associated with clinical manifestation of LSS remains to be investigated.

Medial acetabular wall breach in total hip arthroplasty - is full-weight-bearing possible?

BACKGROUND: A breach of the medial acetabular wall is a phenomenon seen frequently due to over-reaming during total hip arthroplasty (THA). The consequences of this issue are not fully understood particularly in cementless THA. A retrospective study was performed to answer whether: immediate postoperative full-weight-bearing in the presence of a medial acetabular wall breach after THA results in more short-term revisions of the acetabular component, and increases the risk for migration of the acetabular component? HYPOTHESIS: Immediate full-weight-bearing in the presence of a medial breach is not associated with an increased likelihood for acetabular-related revision surgery or migration of the cup. PATIENTS AND METHODS: In this retrospective cohort study, consecutive patients (n=95; mean age 68±13 years; 67 female) who underwent THA with an uncemented acetabular component were identified and a retrospective chart review was performed (follow-up 23±17 months, range 6 to 79 months). The presence of a postoperative radiographic medial acetabular breach was documented and the need for revision surgery and the rate of acetabular component migration were assessed during follow-up. RESULTS: Some extent of radiographic medial acetabular wall breach was seen in 26/95 patients (27%). With regard to the primary outcome, 2/95 patients (2%) required revision surgery during follow-up. All revision surgeries occurred in the group without a medial breach (p=0.280) for causes related to the femoral or the head components. Persistent pain was present in 1/26 patients (3.8%) in the medial breach group and 8/69 patients in the control group (11.6%; p=0.436). In the radiographic follow-up (n=81), there was no significant difference between the control group and the medial breach group with regard to cup migration (Δ ilio-ischial overlap [distance between the ilio-ischial line and a parallel line tangential to the acetabular cup on AP views]: -0.5±0.9mm [range, -2.9 to 0.8] vs. -0.3±1.7mm [range, -1.9 to 2.2], Δ overlap tangent [defined as the distance between the two crossings of ilio-ischial line and the acetabular component on AP views]: -2.2±6.1mm [range, -21.4 to 0.0] vs. 0.4±6.9mm [range, -6.2 to 17.6]). Similarly, according to variation in the ilio-ischial overlap distance between postoperative and follow-up on pelvic AP views, 0/56 hips (0%) had cup migration ≥ 5mm in the control group versus 1/25 (4%) in the medial breach cohort (p=0.3). DISCUSSION: In this retrospective observation of patients with immediate postoperative full-weight-bearing after THA, a radiographic breach of the medial acetabular wall was not associated with an increased risk for short-term revision surgery or radiographic migration at follow-up. According to the findings of this study and in the light of previous biomechanical studies, there is no clear evidence for postoperative partial weight-bearing in case of a medial breach as far as the surgeon feels that the acetabular component is stable. LEVEL OF EVIDENCE: IV, Retrospective cohort study.

Facial movement before and after masseteric-facial nerves anastomosis: a three-dimensional optoelectronic pilot study.

To quantify the effects of facial palsy reanimation, 14 patients aged 17-66 years were analysed. All patients had unilateral facial paralysis, and were candidates for surgical masseteric to facial nerve anastomosis. Two patient groups were measured: seven patients were waiting for surgery, the other seven patients had already been submitted to surgery, and had regained facial mimicry. Each patient performed three facial animations: brow raise; free smile; lip purse. These were recorded using an optoelectronic motion analyser. The three-dimensional coordinates of facial landmarks were obtained, their movements were computed, and asymmetry indices calculated (differential movements between the two hemi-faces: healthy and paretic/rehabilitated). Before surgery, mobility was larger in the healthy than in the paretic side; after surgery, the differences were reduced (brow raise and lip purse), or even reversed (smile). Before surgery, lip purse was performed with significant labial asymmetry (p=0.042; larger healthy side movement). After surgery, asymmetry indices reduced. Total labial asymmetry during smiling was significantly different from 0 before surgery (p=0.018, larger healthy side movement). After surgery, all asymmetry indices became non-significant. Before surgery the lateral displacements of all labial landmarks were towards the healthy side, while they normalized after surgery.