scholarly journals Cervical curvature changes following laminectomy with lateral mass screw fixation: Does it relate with spinal cord shift and clinical efficacy

2020 ◽  
Author(s):  
Shu-bing Hou ◽  
Xian-ze Sun ◽  
Feng-yu Liu ◽  
Rui Gong ◽  
Zheng-qi Zhao ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Clinical Efficacy ◽  
Screw Fixation ◽  
Lateral Mass ◽  
Cervical Lordosis ◽  
Lateral Mass Screw ◽  
C5 Palsy ◽  
Significant Difference ◽  
Group A ◽  
Group B

Abstract Background Laminectomy with lateral mass screw fixation (LCSF) is an effective operation type for the treatment of cervical spondylotic myelopathy (CSM), however, the cervical curvature loss is often observed in some patients after operation. Will the cervical curvature change affect the spinal cord drift distance and the decompression effect? The aim of this study is to investigate the effects of different cervical curvature on spinal cord drift distance and clinical efficacy. Methods A total of 78 cases of CSM patients underwent LCSF were included in this retrospective study. The cervical curvature was measured according to the Bordon method 6 months after the operation, and the patients were divided into two groups. Group A: 42 cases with reduced cervical curvature (0 < the cervical lordosis depth < 7 mm) and group B: 36 cases with normal cervical curvature (7 mm ≤ the cervical lordosis depth ≤ 17 mm). The spinal cord drift distance, laminectomy width, neurological functional recovery, axial symptom (AS) severity and the occurrence of C5 palsy in both groups were observed. Results The cervical lordosis depth was (5.1 ± 1.2) mm in group A and (12.3 ± 2.4) mm in group B (P < 0.05). The laminectomy width was (21.5 ± 2.6) mm in group A and (21.9 ± 2.8) mm in group B (P > 0.05). The spinal cord drift distance was (1.9 ± 0.4) mm in group A and (2.6 ± 0.7) mm in group B, with statistically significant difference between the two groups (P < 0.05). The postoperative JOA scores in both groups were significantly increased (P < 0.05), and there was no significant difference in the neurological recovery rate (61.5% vs 62.7%) between the two groups (P > 0.05). According to the grading standard of AS, the severity of AS in group A was significantly higher than that in group B (P < 0.05). Three cases (7.1%) of C5 palsy occurred in group A and 4 cases (11.1%) occurred in group B (P > 0.05). Conclusion After LCSF, more than half of the patients had cervical curvature loss. The smaller of the cervical curvature was, the shorter distance the spinal cord drifted backward. The loss of cervical curvature was related to the severity of axial symptoms, rather than the improvement of neurological function and C5 palsy.

Relationship of Change in Cervical Curvature after Laminectomy with Lateral Mass Screw Fixation to Spinal Cord Shift and Clinical Efficacy

2021 ◽  
Author(s):  
Shu-bing Hou ◽  
Xian-ze Sun ◽  
Feng-yu Liu ◽  
Rui Gong ◽  
Zheng-qi Zhao ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Clinical Efficacy ◽  
Screw Fixation ◽  
Japanese Orthopaedic Association ◽  
Lateral Mass ◽  
Cervical Lordosis ◽  
Lateral Mass Screw ◽  
C5 Palsy ◽  
Group A ◽  
Group B

Abstract Background and Study Aims Although laminectomy with lateral mass screw fixation (LCSF) is an effective surgical treatment for cervical spondylotic myelopathy (CSM), loss of cervical curvature may result. This study aimed to investigate the effect of cervical curvature on spinal cord drift distance and clinical efficacy. Patients and Methods We retrospectively analyzed 78 consecutive CSM patients with normal cervical curvature who underwent LCSF. Cervical curvature was measured according to Borden's method 6 months after surgery. Study patients were divided into two groups: group A, reduced cervical curvature (cervical lordosis depth 0–7mm; n = 42); and group B, normal cervical curvature (cervical lordosis depth 7–17mm; n = 36). Spinal cord drift distance, laminectomy width, neurologic functional recovery, axial symptom (AS) severity, and incidence of C5 palsy were measured and compared. Results Cervical lordosis depth was 5.1 ± 1.2 mm in group A and 12.3 ± 2.4 mm in group B (p < 0.05). Laminectomy width was 21.5 ± 2.6 mm in group A and 21.9 ± 2.8 mm in group B (p > 0.05). Spinal cord drift distance was significantly shorter in group A (1.9 ± 0.4 vs. 2.6 ± 0.7 mm; p < 0.05). The Japanese Orthopaedic Association (JOA) score significantly increased after surgery in both groups (p < 0.05). Neurologic recovery rate did not differ between the two groups (61.5 vs. 62.7%; p > 0.05). AS severity was significantly higher in group A (p < 0.05). C5 palsy occurred in three group A patients (7.1%) and four group B patients (11.1%), but the difference was not significant (p > 0.05). Conclusion After LCSF, 53.8% of the patients developed loss of cervical curvature. A smaller cervical curvature resulted in a shorter spinal cord drift distance. Loss of cervical curvature was related to AS severity but not improvement of neurologic function or incidence of C5 palsy.

scholarly journals Comparison of the clinical efficacy of two fixation methods combined with OLIF in the treatment of lumbar spondylolisthesis

2021 ◽  
Author(s):  
Xinliang Zhang ◽  
Yunshan Guo ◽  
Yibing Li
Keyword(s):  
Clinical Efficacy ◽  
Screw Fixation ◽  
Fusion Rate ◽  
Imaging Data ◽  
Fixation Methods ◽  
Post Surgery ◽  
Significant Difference ◽  
Group A ◽  
Group B ◽  
Lumbar Spondylolisthesis

Abstract Background To observe the clinical efficacy of an anterior single rob-screw fixation (ASRSF) combined with the oblique lumbar intervertebral fusion (OLIF) approach compared with a posterior percutaneous screw fixation(PPSF) combined with OLIF in the treatment of lumbar spondylolisthesis. Methods This is a retrospective case-control study. Patients with lumbar spondylolisthesis treated with either ASRSF combined with OLIF or PPSF combined with OLIF from January 2016 to January 2018 were enrolled in this study. None of the patients had posterior decompression. The visual analog scale (VAS) and Oswestry dysfunction index (ODI) were used for clinical efficacy assessment. The pre- and post-operational disc height, height of foramen, subsidence and migration of cages, fusion rate, and surgery-related complications were compared between the two groups. Results Fifty-three patients were included in this single-center study. According to the fixation methods, patients were divided into the ASRSF group (group A, 25 cases) and the PPSF group (group B, 28 cases). There was no statistical difference in surgery-related complications between groups. There was a significant difference in the VAS score at 1 week post-surgery(2.3 ± 0.5Vs3.5 ± 0.4, P = 0.01), and 3 months post-operation (2.2 ± 0.3VS 3.0 ± 0.3, P = 0.01). Comparison of post-operative imaging data showed that there was a significant difference in the height of the foramen between groups at 3 months post-surgery(18.1 ± 2.3 mm Vs 16.9 ± 1.9 mm, P = 0.04). At 24 months post-surgery, the ODI was 12.65 ± 3.6 in group A and 19.1 ± 3.4 in group B (P = 0.01). Twelve months after surgery, the fusion rate in group A was 72.0% and78.6% in group B (not statistically significant, P = 0.75). Fusions were identified in all patients at 24 months post-surgery. Conclusion Compared to PPSF, ASRSF combined with OLIF for lumbar spondylolisthesis can reduce post-operative low back pain in the early stages, maintain the height of the foramen superiorly, and improve the performance of lumbar function.

scholarly journals Clinical and Radiological Evaluation of Cervical Spondylotic Myelopathy Operated With Posterior Decompression and Lateral Mass Fixation- a Retrospective Review with Minimum Two Years Follow-Up

2021 ◽  
Vol 2 (1) ◽  
Keyword(s):  
Clinical Outcome ◽  
Neck Pain ◽  
Cervical Spondylotic Myelopathy ◽  
Screw Fixation ◽  
Lateral Mass ◽  
Cervical Lordosis ◽  
Lateral Mass Screw ◽  
C5 Palsy ◽  
Radiological Parameters

Objective: There is controversy in surgical management of cervical spondylotic myelopathy (CSM); a few group encourage only laminectomy or laminoplasty while the others emphasize on lateral mass fixation along with laminectomy. Cervical lordosis is an important factor for maintaining posture neck and preventing postoperative axial neck pain. Literature has reported that cervical lordosis less than -20 degrees is often responsible for neck pain. The purpose of this study was to evaluate clinical outcome and radiological parameters after posterior cervical laminectomy and fixation in CSM. Material and Methods: This retrospective study included 37 patients operated with posterior cervical decompression and lateral mass screw fixation with minimum two-year follow-up. All patients were operated for CSM. All were operated by a single surgeon and followed up at six weeks, twelve weeks, six months, one year and yearly afterwards. Clinical outcome and radiological parameters were analyzed for clinical improvement [European Myelopathy Score (EMS)] and cervical lordotic angle. Results: Average age 68±8.3 years. The cervical lordotic angle of -23.02±4.19 degrees was maintained in patients operated with lateral mass screw fixations along with laminectomy at final follow-up. The EMS and VAS score showed significant improvement postoperatively from 15.7 to 13.6 (p<0.05) and 8.1 to 1.5 (p<0.05), respectively. Three patients had postoperative C5 palsy that recovered completely within three months. Two patients expired within a few months after surgery due to acute myocardial infarction and respiratory arrest, respectively. There were three patients who had postoperative C5 palsy, which recovered completely within three months postoperatively. There was no permanent postoperative neurological deficit noticed in the series. Conclusion: Posterior cervical lateral mass screw fixation for CSM gives satisfactory clinical outcome and maintains cervical lordosis. Lateral mass fixation with

scholarly journals Comparison Between With Kirschner-wires Only And Combined Screw Fixation in Proximal Reverse Chevron osteotomy(PCMO) For Hallux Valgus Deformity

2017 ◽  
Vol 2 (3) ◽  
pp. 2473011417S0002
Author(s):  
Hwa Jun Kang ◽  
Hong-Geun Jung ◽  
Jong-Soo Lee ◽  
Sungwook Kim ◽  
Mao Yuan Sun
Keyword(s):  
Hallux Valgus ◽  
Screw Fixation ◽  
Fixation Method ◽  
Kirschner Wires ◽  
Significant Difference ◽  
Group A ◽  
The Mean ◽  
Group B ◽  
Severe Hallux Valgus

Category: Bunion Introduction/Purpose: Kirschner-wires fixation, sometimes we have encountered pin irritation or pull-out. This is the reason why we consider additional fixation. Moreover, there are few reports according to comparison of fixation method, and Most of them focused on comparison K-wires or screw fixation only. Purpose of study is to compare clinical and radiographic outcome between Kirschner-wires only and combined screw fixation. Methods: The study included two different groups according to fixation methods. One with Kirschner-wires fixation (KW group) included 117 feet(of 98 patients), the other with combined screw fixation (KWS group) 56 feet (of 40 patients) with moderate to severe hallux valgus. Clinically, the preoperative and final follow-up visual analog scale (VAS) pain scores, the preoperative and final follow-up American Orthopaedic Foot & Ankle Society (AOFAS) hallux metatarsophalangeal (MTP)-interphalangeal (IP) scores, and patient satisfaction after the surgery were evaluated. Radiographically, the hallux valgus angle (HVA), intermetatarsal angle (IMA), medial sesamoid position (MSP), and first to fifth metatarsal width (1-5MTW) were analyzed before and after surgery. Results: The mean AOFAS score improved preoperative 65.5 to 95.3 at final follow up in group A, while preoperative 56.5 to 88.6 at final follow up. Pain VAS decreased from 5.7 to 0.5 in group A, whereas from 6.2 to 1.6 in group B. The mean HVA all improved from preoperative 38.5 to 9.3 at final follow up in group A and 34.7 to 9.1 in group B. The mean IMA and MSP also improved significantly at final follow up. In comparative analysis, the IMA did not show significant difference between postoperative and final state in group A, while showed significant increase in group B. Conclusion: We achieved favorable clinical and radiographic outcomes with minimal complications in patient with moderate to severe hallux valgus in both groups. However, this study shows no statistically significant difference in IMA during follow-up period and lower recurrence rate. Therefore we need to consider combined fixation method to provide better stability and can expect lower recurrence rate.

Bone Marrow Transplantation or G-CSF Treatment Can Accelerate Recovery of Injured Spinal Cord in Mice.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 4181-4181
Author(s):  
Damianos Sotiropoulos ◽  
Eleni Siotou ◽  
Evangelia Athanasiou ◽  
Christos Kalpouzos ◽  
Panayotis Kaloyannidis ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Bone Marrow ◽  
Bone Marrow Cells ◽  
Control Group ◽  
Significant Difference ◽  
Cord Injury ◽  
Group A ◽  
B Mice ◽  
The Mean ◽  
Group B

Abstract Mice, unlike rats and humans, have a self recovery mechanism of spinal cord injury. Whether the hematopoietic system is involved in this mechanism is under investigation. In this study we tested whether bone marrow cells transplanted or mobilized by a growth factor in mice with spinal cord injury, can accelerate the recovery. C57bl/6 female mice 10 to 12 weeks of age underwent spinal cord incision in an open operation. The injury was performed as a complete transection including the dura mater and the whole circumference of the cord at the T10-T11 intervertebral space with a micro scalpel (No 11). Group A mice received 200μg/kg/day G-CSF subcutaneously for 7 days, starting 24 hours after operation. Group B mice received 106 light density bone marrow cells from C576bl/6 donor mice intravenously 24 hours after operation. Control group mice received no treatment. Histological evaluation was performed at 48 hours, 1 week, 3 weeks and 5 weeks postoperatively. Paraffin embedded longitudinal samples of spinal cord were cut as serial sections. Spinal cord damage was estimated by measuring the maximum diameter of the area of axonal damage and disruption of astrocytic network using immunostaining for neurofilaments and GFAP. Antibodies against CD68 were applied to identify macrophage aggregations. All measurements were performed by morphometric photo analysis. The volume of fibroblastic infiltration was estimated using a grading system (0–7), based on Van Gieson stain for connective tissue. Functional deficits and recovery over time were evaluated by testing hind limb reflex and coordinated motor function (Kuhn and Wrathal functional tests, modified by Seki et al, 2002). All tests have been videotaped. Outcome scores at 48 hours, 1 week, 3 weeks and 5 weeks postoperatively for the control group, group A and group B mice were analyzed with the Mann-Whitney U test. 48 hours post operatively all mice in all groups were paralyzed in both hind limbs. Gradual improvement was observed in all groups. At week 3 there was a significant difference between the mean scores of functional tests for both treated groups (A and B) compared with the mean scores of the control group. Statistically significant difference (p&lt;0,05) was observed in 5 out of 7 tests for group A and in 3 out of 7 tests for group B. Same difference between Group A mice and control group mice was observed by 5 weeks, while group B had no statistically significant difference. No animal in any of the groups had a complete recovery 5 weeks postoperatively. Spinal cord in control group mice showed a gradually increase of fibroblastic infiltration until 5 week which entirely separated the two ends of the cord. In group A and group B mice a significant decrease of fibroblastic infiltration was observed at week 5 compared with week 3. Macrophage aggregations were evident at weeks 1 and 5 but not at week 3 in all groups. In conclusion our results indicate that light density bone marrow transplanted cells or G-CSF treatment can accelerate spinal cord injured mice recovery. It is possible that this is associated with a decrease in fibroblastic infiltration of spinal cord. Macrophage aggregation may also play an important role in the mechanism of recovery in mice, while in rats a different reaction including cavitation and delayed demyelination prohibits neurological recovery.

The clinical effect of Chitosan nanoparticles against Helicobacter pylori

2020 ◽  
Vol 10 (7) ◽  
pp. 1116-1121
Author(s):  
Jing Wang ◽  
Xinhong Wang ◽  
Min Li ◽  
Suxiang Fan
Keyword(s):  
Triple Therapy ◽  
Clinical Efficacy ◽  
Adverse Reactions ◽  
Chitosan Nanoparticles ◽  
High Dose ◽  
Significant Difference ◽  
Oral Liquid ◽  
Group A ◽  
The Difference ◽  
Group B

The objective of this study was to observe the clinical effect of Chitosan nanoparticles therapy on Helicobacter pylori (HP) infection. Three treatment groups (A, B, and control group C) were randomly assigned with 60 cases of HP each, making 180 cases. Group C received standard triple therapy (omeprazole + amoxicillin + clarithromycin), group A got a routine dose of Chitosan nanoparticles plus triple therapy, and group B got a high dose of Chitosan nanoparticles plus triple therapy. The course of treatment in each group was 7 days. The eradication rate, clinical efficacy and adverse reactions were observed. Up to 172 patients finished the experiment, with 59 patients in Group A, 57 in Group B and 56 in Group C. In a total analysis set (FAS), the eradication rates of HP in Group A, Group B and Group C were 80.00%, 80.70%, and 71.67%, respectively. There was no significant difference between the two groups (P > 0.05). In accordance with the PPS, the HP eradication rates of group A, B, and C were 81.36%, 80.70% and 76.79%, respectively, and there was no significant difference between the two groups (P > 0.05). The clinical efficacy of group A, B, and C were 91.67%, 91.23%, and 70.00%, respectively. The differences among the three groups were statistically significant (P < 0.05). In accordance with the PPS, the clinical efficacy of group A, B and C was 93.22%, 91.23%, and 75.00%, respectively. With a P-value of less than 0.05, the results indicated that the difference between the two groups was statistically significant. There were 21 adverse reactions in the experiment, including 3 in group A, 6 in group B, and 12 in group C. The difference was statistically significant (P < 0.05) between group A and B compared with group C, the difference was statistically significant (P < 0.05); the difference between group A and group B was statistically significant (P < 0.05). In conclusion the therapeutic effect of Chitosan nanoparticles and oral liquid, combined with triple therapy on HP infection is satisfactory, with less adverse reactions are. However, the findings suggest that it is not desirable to use a high dose Chitosan nanoparticles and oral liquid.

scholarly journals Comparative Efficacy of Intraoperative Extracorporeal Irradiated and Alcohol Inactivated Autograft Reimplantation in Management of Osteosarcomas– A Multicentre Retrospective Study.

2021 ◽  
Author(s):  
Meitao Xu ◽  
Ming Xu ◽  
Shuai Zhang ◽  
Hanqing Li ◽  
Qiuchi AI ◽  
...  
Keyword(s):  
Limb Salvage ◽  
Clinical Efficacy ◽  
Salvage Surgery ◽  
Limb Salvage Surgery ◽  
Malignant Bone Tumours ◽  
Significant Difference ◽  
Group A ◽  
The Mean ◽  
Group B ◽  
Extracorporeal Irradiation

Abstract Background: The biologic bone reconstruction in the treatment of malignant bone tumours for the limb salvage surgery has always been a controversial strategie. Vary inactivation methods, convenient, stable, curative effect and economy need to be considered. This study aims to compare the clinical efficacy between intraoperative extracorporeal irradiated and alcohol inactivated autograft reimplantation methods for limb salvage surgery with osteosarcomas. Methods: We retrospectively analysed 28 patients with osteosarcomas, 14 patients treated with intraoperative cobalt 60 irradiation and reimplantation treatment (Group A), 14 patients treated by alcohol-inactivated autograft reimplantation (Group B). The postoperative complications and clinical efficacy was compared by statistical analysis. Results: The local recurrence rate was 14.3% in each group. Complete bony union was achieved in 64.3% in group A and 71.4% in group B. The overall 5-year survival rate was 71.4% in group A and 78.6% in group B. The mean MSTS score was 25.33 ± 4.72 (range 15–30 ) in group A and 24.00 ± 5.85 (range 15–30 ) in group B. The mean ISOLS score was 25.79 ± 5.13 (range 20–36 ) in group A and 26.14 ± 5.33 (range 20–30 ) in group B. P < 0.05 was considered to indicate a significant difference, there was no difference in the long-term clinical efficacy between the extracorporeal irradiation and alcohol-inactivated methods.Conclusions: For limb salvage surgery with osteosarcomas, either intraoperative extracorporeal irradiation or alcohol-inactivated autograft repimlantation had equivalent outcomes for biological reconstruction. The alcohol-inactivated technology could be a much more convenient and cheap treatment to reconstruct bone defects. Additional studies and more case studies are needed to fully evaluate the clinical efficacy and safety of the alcohol-inactivated surgical approach.

scholarly journals Metabolomics-Based Clinical Efficacy of Compound Shenlu Granule, a Chinese Patent Medicine, in the Supportive Management of Aplastic Anemia Patients: A Randomized Controlled Pilot Trial

2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Zhou Feng ◽  
Xiaoying Hu ◽  
Weiying Qu ◽  
Xiaoqin Zhu ◽  
Jiaying Lu ◽  
...  
Keyword(s):  
Aplastic Anemia ◽  
Clinical Efficacy ◽  
Pilot Trial ◽  
Control Group ◽  
Efficacy Rate ◽  
Metabolomics Data ◽  
Significant Difference ◽  
Group A ◽  
Group B ◽  
Tcm Syndrome

Objective. To explore the clinical efficacy and mechanism of compound Shenlu granule (SLG) treatment in patients with aplastic anemia (AA). Methods. A total of 89 AA patients were randomly divided into an SLG supportive group (group A, n = 44) and a control group (group B, n = 45) while continuing Western medical management. After 6 months, hemograms, traditional Chinese medicine (TCM) syndrome scores, and overall clinical efficacy rate were assessed. Serum metabolomics characteristics were observed using ultraperformance liquid chromatography-mass spectrometry after SLG intervention. Results. The levels of red blood cell (RBC), hemoglobin (Hb), and platelet (PLT) were increased in both groups after treatment for 6 months ( P < 0.05 ), and in group A, the elevation of PLT became much more significant ( P < 0.01 ). The TCM syndrome score was lower in group A than in group B after treatment ( P < 0.05 ). Metabolomics data showed a significant difference in the patients using SLG after 6 months, and 14 biomarkers were identified. Conclusion. SLG supportive treatment showed positive results in patients with AA, and metabolomics data indicated that SLG influenced aminoacyl-tRNA biosynthesis and glycerophospholipid metabolism to gradually return to normal.

Risk factors for intraoperative lateral mass fracture of lateral mass screw fixation in the subaxial cervical spine

2014 ◽  
Vol 20 (1) ◽  
pp. 11-17 ◽  
Author(s):  
Shinichi Inoue ◽  
Tokuhide Moriyama ◽  
Toshiya Tachibana ◽  
Fumiaki Okada ◽  
Keishi Maruo ◽  
...  
Keyword(s):  
Risk Factors ◽  
Cervical Spine ◽  
Screw Fixation ◽  
Lateral Mass ◽  
Lateral Mass Screw ◽  
Screw Insertion ◽  
Significant Difference ◽  
Independent Risk Factors ◽  
Lateral Mass Fracture ◽  
Destructive Spondyloarthropathy

ObjectAlthough lateral mass screw fixation for the cervical spine is a safe technique, lateral mass fracture during screw fixation is occasionally encountered intraoperatively. This event is regarded as a minor complication; however, it poses difficulties in management that may affect fixation stability and clinical outcome. The purpose of this study is to determine the incidence and etiology of lateral mass fractures during cervical lateral mass screw fixation.MethodsA retrospective clinical review of patient records was performed in 117 consecutive patients (mean age 57 years, range 15–86 years) who underwent lateral mass screw fixation using a modified Magerl method from 1997 to 2010 at a single institution. A total of 555 lateral masses were included in this study. The outer diameters of the screws were 3.5 or 4.0 mm. In the retrospective clinical analysis, the incidence of intraoperative lateral mass fractures was reviewed. Potential risk factors for this complication were assessed using multivariate analysis.ResultsThe incidence of lateral mass fractures during cervical lateral mass screw fixation was 4.7% (26 lateral masses) among all cases. Among the disorders, the incidence was highest in patients with destructive spondyloarthropathy (DSA) (18.8%, 12 lateral masses). There was no significant difference with respect to lateral mass fracture between the use of 4.0-mm screws (5.6%) and 3.5-mm screws (3.6%). Independent risk factors identified by logistic regression were DSA (OR 7.89, p < 0.001) and screw insertion in the C-6 lateral masses (OR 2.80, p = 0.018).ConclusionsThe overall incidence of lateral mass fracture during cervical lateral mass screw fixation was 4.7%. Destructive spondyloarthropathy as an underlying cause of morbidity and screw placement in the C-6 lateral mass were identified as independent risk factors. Use of a 4.0-mm screw in patients with DSA may be a principal risk factor for this complication.

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