Risk factors of revision operation and early revision for adjacent segment degeneration after lumbar fusion surgery: a case-control study.

BACKGROUND CONTEXT: Adjacent segment degeneration (ASD) following lumbar fusion operation is common and can occur at varying timepoints after index surgery. An early revision operation for ASD, however, signifies a short symptom-free period and might increase the risk of successive surgeries. PURPOSE: We aimed to elucidate the overall risk factors associated with revision surgeries for ASD with distinct attention to early revisions. STUDY DESIGN/SETTING: Retrospective, case-control study. PATIENT SAMPLE: The study included 86 patients who underwent revision operations for ASD after lumbar fusion in the revision group and 166 patients who did not for at least 5 years after index surgery. OUTCOME MEASURES: Sagittal parameters, Pfirrmann grading, facet degeneration grading, and disc space height (DSH) of adjacent segments were assessed. METHODS: Revision operations within 5 years postsurgery were defined as early revision. We compared the revision and no-revision groups as well as the early- and late-revision groups. RESULTS: The revision group demonstrated a significantly greater preoperative C7-S1 sagittal vertical axis (SVA) (p=.001), postoperative C7-S1 SVA (p<.001), and postoperative pelvic incidence (PI)-lumbar lordosis (LL) (p<.001) than those in the no-revision group. Preoperative DSH of the proximal adjunct segment (p=.001), postoperative PI-LL (p=.014), and postoperative C7-S1 SVA (p=.037) exhibited significant association with ASD in logistic regression analysis. The early-revision group had a significantly higher patient age (p=.001) and a greater number of levels fused (p=.030) than those in the late-revision group. Multivariate Cox regression analysis demonstrated that old age (p=.045), a significant number of levels fused (p=.047), and a narrow preoperative DSH of the proximal adjacent level (p=.011) were risk factors for early revision. CONCLUSIONS: Postoperative sagittal imbalance, including significant PI-LL and C7-S1 SVA were risk factors for revision operation for ASD but not for early revision. These factors are likely to affect the long-term risk of revision operation due to ASD and thus are not considered risk factors for early revision. Narrow DSH of the proximal adjacent level increased the risks of both revision and early revision surgeries. Moreover, old age and a significant number of levels fused further increased the risk for early revision for ASD.

Comparison of clinical outcomes between patellar resurfacing and patellar non-resurfacing in cruciate retaining total knee arthroplasty.

BACKGROUND: It is not established whether patellar resurfacing is better than patellar non-resurfacing during total knee arthroplasty (TKA). This study was to compare the clinical outcomes between groups with patellar resurfacing and non-resurfacing during cruciate retaining (CR) TKA. METHODS: In this retrospective cohort study, subjects undergoing primary CR TKA for osteoarthritis between 2012 and 2019 were included. Of 500 subjects, 250 had patellar resurfacing (group 1) and 250 had patellar non-resurfacing (group 2) CR TKA. Knee society knee score (KSKS), knee society function score (KSFS), Western Ontario and McMaster Universities Osteoarthritis (WOMAC) scale, Kujala score, anterior knee pain, patellar compression test and range of motion (ROM) of the replaced knee were assessed and compared between the two groups. RESULTS: There were no significant differences in KSKS, KSFS, WOMAC scale, Kujala score, prevalence of anterior knee pain and ROM of the replaced knee between the two groups at the last follow-up (p > .05). Group 2 had more subjects with positive patellar compression test than group 1 at the last follow-up (p = .010). CONCLUSIONS: Clinical and functional outcomes of the replaced knee were not different between patellar resurfacing and non-resurfacing groups. Anterior knee pain was significantly reduced after total knee arthroplasty regardless of patellar resurfacing. LEVEL OF EVIDENCE: Retrospective cohort study, Level III.

Intraoperative patellar maltracking and postoperative radiographic patellar malalignment were more frequent in cases of complete medial collateral ligament release in cruciate-retaining total knee arthroplasty.

BACKGROUND: Patellar maltracking after total knee arthroplasty (TKA) can lead to significant patellofemoral complications such as anterior knee pain, increased component wear, and a higher risk of component loosening, patellar fracture, and instability. This study was to investigate the preoperative and operative variables that significantly affect patellar tracking after cruciate-retaining TKA. METHODS: We studied 142 knee joints in patients who had undergone TKA: the knees were dichotomized based on postoperative patellar tracking, which was evaluated on patellar skyline, axial-projection radiographs: group 1, normal patellar tracking (lateral tilt ≤ 10° and displacement ≤ 3 mm) and group 2, patellar maltracking (lateral tilt > 10° or displacement > 3 mm). The patients' demographic data and clinical and radiographic measurements obtained before and after surgery were compared between the two groups. RESULTS: Preoperative lateral patellar displacement was greater (4.1 ± 2.6 mm vs. 6.0 ± 3.5 mm), as was the frequency of medial collateral ligament (MCL) release (3/67 vs. 24/75) in group 2 than in group 1 (p < 0.001 and p < 0.001, respectively). The distal femur was cut in a greater degree of valgus in group 1 than in group 2. (6.3 ± 0.8° vs. 6.0 ± 0.8°) (p = 0.034). CONCLUSIONS: Complete release of the MCL during surgery was associated with patellar maltracking (logistic regression: p = 0.005, odds ratio = 20.592). Surgeons should attend to patellar tracking during surgery in medially tight knees. LEVEL OF EVIDENCE: Retrospective comparative study, level III.

Can early surgery reduce the need to packed red blood cell transfusion in elderly patients with intertrochanteric femur fractures?

INTRODUCTION: This study was designed to compare and analyse the amount of packed red blood cell transfusions (PRBCTs) in relation to surgical timing in elderly patients undergoing cephalomedullary nailing due to intertrochanteric fractures. MATERIALS AND METHODS: A total of 110 patients (24 men, 86 women) who had received cephalomedullary nailing for intertrochanteric fractures were retrospectively investigated. A restrictive transfusion strategy was followed during the peri-operative period. Patient characteristics and fracture classifications, methods of anaesthesia, time interval from admission to surgery (TI) and operative duration (OD) were investigated. The amount of PRBCTs was measured and categorised as pre-operative, post-operative and entire peri-operative values. The patients were divided into early surgery (ES) and delayed surgery (DS) groups based on surgical treatment within or after 48 h of admission. In addition, multiple regression analysis including TI and other factors likely to affect blood loss and PRBCT was conducted to objectively evaluate the impact of TI on the amount of the entire peri-operative PRBCT. RESULTS: The patients had a mean age of 82.6 years (range, 68-98), mean TI of 41.1 h (range, 5-110) and mean OD of 37 min (range, 15-90). Although the amount of pre-operative PRBCT was significantly different between the ES and DS groups (36.2 ml vs. 168.3 ml, p < 0.001), they displayed no remarkable difference regarding post-operative and the entire peri-operative amount of PRBCTs (279.7 ml vs. 189.8 ml, p = 0.064 and 315.9 ml vs. 358.0 ml, p = 0.992, respectively). The results from multiple regression analysis demonstrated that TI did not significantly affect the amount of the entire peri-operative PRBCT. CONCLUSIONS: If an appropriate transfusion strategy is adopted, TI does not seem to affect the amount of peri-operative PRBCT in elderly patients with intertrochanteric fractures. Nevertheless, careful transfusion management with a view to compensating for any drop in pre-operative haemoglobin is necessary when surgery is delayed.

Fate of Ossification of Posterior Longitudinal Ligament Following Anterior Cervical Fusion: Progression of Cervical Ossification of Posterior Longitudinal Ligament After Vertebral Body Sliding Osteotomy or Laminoplasty.

OBJECTIVE: In the treatment of ossification of posterior longitudinal ligament (OPLL)-induced cervical myelopathy, laminoplasty (LMP) is the most widely used surgical procedure. However, the progression of ossification masses is a well-known complication of LMP. This study aimed to investigate whether the novel anterior cervical decompression technique (vertebral body sliding osteotomy; VBSO) based on anterior column fusion suppresses the progression of OPLL compared with motion-preserving posterior decompression surgery (LMP). METHODS: All 77 consecutive patients (VBSO group, n = 33; LMP group, n = 44) who underwent VBSO or LMP for cervical OPLL at our institute between January 2012 and November 2017 were included. A total of 62 and 86 cervical motion segments in the VBSO and LMP groups were investigated, respectively. The OPLL thickness was measured twice (immediate postoperative and final follow-up), and the change of OPLL thickness was compared between the 2 groups. RESULTS: The increase in OPLL thickness in the VBSO group (-0.18 ± 0.24 mm) was significantly smaller than that in the LMP group (1.0 ± 0.9 mm, P < 0.001). Interestingly, in some patients, suppressed OPLL progression and decreased OPLL thickness were observed. CONCLUSIONS: The solid fusion of the anterior column by VBSO is associated with the lower incidence of OPLL growth and potential for growth arrest.

Ipsilateral Pedicle Stress Fracture After Endoscopic Foraminal Decompression for Patient with Isthmic Spondylolisthesis.

BACKGROUND: Minimally invasive endoscopic spine surgery is useful for the treatment of various spinal conditions. Although surgery-related complications such as dural injury, exiting nerve root injury, incomplete decompression, and hematoma have been reported, there are few reports of late complications after endoscopic surgery. CASE DESCRIPTION: A 51-year-old man complained of radiating pain to the right leg. The patient underwent endoscopic foraminal decompression under the diagnosis of foraminal stenosis with isthmic type spondylolisthesis (L5-S1). The lower extremity radiating pain was improved after surgery. Six weeks after surgery, the patient's symptoms recurred. The patient experienced a sudden onset of severe low back pain, which was aggravated by any motion of the lumbar spine. Computed tomography scan and magnetic resonance imaging revealed a fracture line with a sclerotic margin at the base of the right pedicle at the L5 level. Because the symptoms significantly interfered with his normal activities of daily living, the patient was treated with a total laminectomy, followed by posterior instrumented fusion. As the indication for endoscopic spinal surgery is widening, endoscopic decompression surgery is being performed for patients with low-grade lumbar spondylolisthesis, regardless of the presence of advanced spinal instability. However, endoscopic decompression surgery may cause damage to the posterior facet joint, which may have worsened the instability and lead to late complications such as progression of spondylolisthesis and pedicle stress fracture. CONCLUSIONS: The surgeon should carefully review risk factors such as isthmic type spondylolisthesis before planning spine surgery and minimize facet joint damage during endoscopic decompression.

Comparison of bispectral index (BIS) and entropy in patients with cerebral palsy during sevoflurane induction.

BACKGROUND: Demand of anesthesia for patients with cerebral palsy is more increasing. But there is still lacking in clinical research regarding how BIS and entropy reflect well on sedative and hypnotic state in patients with cerebral palsy. METHODS: Fifteen patients with cerebral palsy (Group CP) and fifteen patients without cerebral palsy (Group NL) scheduled for elective orthopedic surgery were included in the study. Induction of anesthesia was done by having the patient inhale 1 vol% sevoflurane and 100% oxygen using a total fresh gas flow of 8 L/min. Simultaneously BIS, state entropy (SE), response entropy (RE), end-tidal sevoflurane concentration were recorded every 15 seconds till there was no self respiration. When end-tidal sevoflurane concentration had not risen any more for 30 seconds, we increased inhaled sevoflurane concentration in 1 vol% increments. End point of recording was when self respiration was lost or the time sevoflurane concentration reached 8 vol%. RESULTS: No significant differences in RE, SE, BIS at baseline and end point were found between the two groups. No significant difference in the time reach end point was found between the two groups. BIS, SE and RE correlated with end-tidal sevoflurane concentration in the two groups. CONCLUSIONS: The authors found no significant difference in the entropy values between patients with CP and normal patients. Also, the entropy values could be interpreted like BIS in patients with CP. And BIS showed a stronger correlation with end tidal sevoflurane concentrations than entropy.