scholarly journals Effect of microscopically assisted decompression with micro-hook scalpel in the surgical treatment of ossification of the posterior longitudinal ligament

2019 ◽  
Vol 47 (10) ◽  
pp. 5120-5129 ◽  
Author(s):  
Sheng Yang ◽  
Jianmin Lu ◽  
Dapeng Fu ◽  
Depeng Shang ◽  
Fei Zhou ◽  
...  
Keyword(s):  
Recovery Rate ◽  
Spinal Canal ◽  
Japanese Orthopaedic Association ◽  
Posterior Longitudinal Ligament ◽  
Clinical Effects ◽  
Posterior Surgery ◽  
Vas Score ◽  
Group A ◽  
Group B

Objective This study was performed to investigate the effect of microscopically assisted decompression using a micro-hook scalpel on ossification of the posterior longitudinal ligament (OPLL). Methods Sixty-one patients with OPLL were divided into Group A (posterior surgery with laminectomy of the responsible segment and lateral mass screw fixation) and Group B (anterior cervical corpectomy with intervertebral titanium cage fusion). Neurological function was assessed by the Japanese Orthopaedic Association (JOA) score, visual analog scale (VAS) score, and recovery rate. The fixation status and the result of spinal canal decompression were radiographically assessed. Results In Groups A and B, the JOA score was significantly higher and the VAS score was significantly lower at 1 week postoperatively and at the final follow-up than during the preoperative period. The mean recovery rate in Group A and B was 59.92% ± 13.46% and 62.28% ± 14.00%, respectively. Postoperative radiographs showed good positioning and no damage to the internal fixation materials. The spinal canal was also fully decompressed. Conclusions Microscopically assisted decompression with a micro-hook scalpel in both anterior and posterior surgeries achieved good clinical effects in patients with OPLL.

scholarly journals A comparative study of effectiveness of local injection of autologous platelet rich plasma and injection corticosteroid solution in treatment of plantar fasciitis

2019 ◽  
Vol 5 (2) ◽  
pp. 335
Author(s):  
Vithal Prakash Puri ◽  
Anil Kumar Gaur
Keyword(s):  
Plantar Fasciitis ◽  
Platelet Rich Plasma ◽  
Corticosteroid Injection ◽  
Care Center ◽  
Tertiary Care ◽  
Vas Score ◽  
Visual Analog Scales ◽  
Group A ◽  
Group B

<p class="abstract"><strong>Background:</strong> The heel pain is the most common problem worldwide and it was associated with plantar fasciitis (PF). The condition of treatment is very complex. Platelet-rich plasma (PRP) and injection of corticosteroids is the treatment of PF. This study was designed to access the effect of local PRP and local corticosteroid injection in PF patients.</p><p class="abstract"><strong>Methods:</strong> Sixty patients (between 29 to 60 years of age) with chronic PF were randomized prospectively in single tertiary care center in India. The study conducted from December 2013 to December 2015. All the patients were enrolled according to inclusion criteria and divided into two groups randomized. In group A (n=30) received PRP and group B (n=30) received corticosteroids injections. Visual analog scales (VAS) were filled by all the included patients. The follow-up scheduled at one and six months after complete enrolment of patients.<strong></strong></p><p class="abstract"><strong>Results:</strong> Between both the groups the significantly different observed at one and six months follow-up from the baseline. At one month follow-up significantly improvement in mean VAS score were observed in group B (p&lt;0.001). At six months follow-up significantly improvement in mean VAS score were observed in group A (p&lt;0.001).</p><p class="abstract"><strong>Conclusions:</strong> The present study concluded from the significance difference between both the groups proved promising form of treatment in chronic PF patients. Both the treatment was safe and effective in relieving pain improving function at different time period.</p><p> </p>

scholarly journals Anterior selective stabilization combined with laminoplasty for cervical myelopathy due to massive ossification of the posterior longitudinal ligament: report of early outcomes in 14 patients

2020 ◽  
Vol 33 (1) ◽  
pp. 58-64 ◽  
Author(s):  
Yukitaka Nagamoto ◽  
Motoki Iwasaki ◽  
Shinya Okuda ◽  
Tomiya Matsumoto ◽  
Tsuyoshi Sugiura ◽  
...  
Keyword(s):  
Cervical Myelopathy ◽  
Recovery Rate ◽  
Japanese Orthopaedic Association ◽  
Posterior Longitudinal Ligament ◽  
Radiographic Parameters ◽  
Selective Stabilization ◽  
The Mean ◽  
Segmental Lordosis ◽  
Compression Level

OBJECTIVESurgical management of massive ossification of the posterior longitudinal ligament (OPLL) is challenging. To reduce surgical complications, the authors have performed anterior selective stabilization combined with laminoplasty (antSS+LP) for massive OPLL since 2012. This study aimed to elucidate the short-term outcome of the antSS+LP procedure.METHODSThe authors’ analysis was based on data from 14 patients who underwent antSS+LP for cervical myelopathy caused by massive OPLL and were followed up for at least 2 years after surgery (mean follow-up duration 3.3 years). Clinical outcome was evaluated preoperatively, at 6 months and 1 year postoperatively, and at the final follow-up using the Japanese Orthopaedic Association (JOA) scoring system for cervical myelopathy and the recovery rate of the JOA score. The following radiographic parameters were measured preoperatively, immediately after surgery, at 1 year after surgery, and at the final follow-up: the C2–7 angle, measured on lateral plain radiographs, and the segmental lordosis angle (SLA), measured on sagittal CT scans. The correlation between radiographic parameters and clinical outcomes was evaluated.RESULTSThe mean JOA score increased from 10.4 before surgery to 13.6 and 13.8 at 6 months and 1 year after surgery, respectively; at the final follow-up the mean score was 13.4. This postoperative recovery was significant (p = 0.004) and was maintained until the final follow-up. No patient required revision surgery due to postoperative neurological deterioration. However, the C2–7 angle gradually deteriorated postoperatively. Similarly, the SLA was significantly increased immediately after surgery, but the improvement was not maintained. The recovery rate at the final follow-up correlated positively with the change in C2–7 angle (r = 0.60, p = 0.03) and the change in SLA (r = 0.72, p < 0.01).CONCLUSIONSAntSS+LP is safe and effective and may be an alternative to anterior decompression and fusion for the treatment of patients with massive OPLL. No postoperative neurological complications or significant postoperative exacerbation of neck pain were observed in our case series. Not only reducing intervertebral motion and decompressing the canal at the maximal compression level but also acquiring segmental lordosis at the maximal compression level are crucial factors for achieving successful outcomes of antSS+LP.

scholarly journals The Effect of Bone Cement Distribution on the Outcome of Percutaneous Vertebroplasty: A Case cohort study

2020 ◽  
Author(s):  
Lei Tan ◽  
Bingtao Wen ◽  
Zhaoqing Guo ◽  
Zhongqiang Chen
Keyword(s):  
Bone Cement ◽  
Vertebral Body ◽  
Kyphotic Angle ◽  
Vas Score ◽  
Angle Change ◽  
Significant Difference ◽  
Cement Distribution ◽  
Group A ◽  
Group B

Abstract Background: To analyze the effect of different types of bone cement distribution after percutaneous vertebroplasty (PVP) in patients with osteoporotic vertebral compression fracture (OVCF). Methods: 137 patients with single level OVCF who underwent PVP were retrospectively analyzed. The patients were divided into two groups according to bone cement distribution. Group A: bone cement contacted both upper and lower endplates; Group B: bone cement missed at least one endplate. Group B was divided into 3 subgroups. Group B1: bone cement only contacted the upper endplates; Group B2: bone cement only contacted the lower endplates; Group B3: bone cement only located in the middle of vertebral body. The visual analogue scale (VAS) score at 24 hours post operation and last follow-up, anterior vertebral height restoration ratio (AVHRR), anterior vertebral height loss ratio (AVHLR), local kyphotic angle change and vertebral body recompression rate were compared. Results: 24 hours post operation, the pain of all groups were significantly improved. The average follow-up time was 15.3 ± 6.3 (6-24) months. At last follow-up, the VAS score of group A was lower than that of group B. There were 14 cases (10.2%) of adjacent vertebral fracture, 5 cases (8.6%) in group A and 9 cases (11.4%) in group B. There were 9 cases (6.6%) of cement leakage, 4 cases (6.9%) in group A and 5 cases (6.3%) in group B. At last follow-up, there were 16 cases (11.7%) of vertebral body recompression, including 3 cases (5.2%) in group A and 13 cases (16.5%) in group B. There was no significant difference in AVHRR between two groups. Local kyphotic angle change was significant larger in group B. At last follow-up, AVHLR in group B was higher than that in group A. In subgroup analysis, there was no significant difference in VAS score, local kyphotic angle change, vertebral recompression rate, AVHRR or AVHLR. Conclusions: If the bone cement fully contacted both the upper and lower endplates, it can better restore the strength of the vertebral body and maintain the height of the vertebral body, reduce the risk of the vertebral body recompression and long-term pain.

scholarly journals A second puncture and injection technique for treating osteoporotic vertebral compression fractures

2019 ◽  
Vol 14 (1) ◽  
Author(s):  
Zhaofei Zhang ◽  
Feng Jiao ◽  
He Huang ◽  
Yonghui Feng ◽  
Chunliang Xie ◽  
...  
Keyword(s):  
Vertebral Fractures ◽  
Cement Leakage ◽  
Vertebral Compression Fractures ◽  
Injection Technique ◽  
Vertebral Height ◽  
Vas Score ◽  
Injection Group ◽  
Group A ◽  
Group B

Abstract Objective To evaluate the clinical effect of the second puncture and injection technique during a percutaneous vertebroplasty (PVP) procedure. Methods Patients treated with a second puncture and injection (group A) or a single puncture and injection (group B) during PVP at our institution during 2010–2017 were reviewed. Vertebral height loss, visual analogue scale (VAS) score, Oswestry disability index (ODI), adjacent vertebral fractures, and cement leakage were compared between the groups. Results A total of 193 patients were enrolled (86 cases in group A, 107 cases in group B). The follow-up period was 15.64 (12–20) months. The loss of anterior (group A 0.01 ± 0.03; group B 0.14 ± 0.17) and middle (group A 0.13 ± 0.12; group B 0.16 ± 0.11) vertebral height in group B was significantly higher than that in group A (P < 0.05). The VAS score and ODI were also significantly higher in group B than in group A at the final follow-up; the VAS score and ODI in group B were 1.65 ± 0.70 and 14.50 ± 4.16, respectively, and those in group A were 1.00 ± 0.74 and 12.81 ± 4.02, respectively (P < 0.05). Three patients in group A and two in group B experienced adjacent vertebral fractures. Regarding mild, moderate, and severe cement leakage, there were 25 (29%), 5 (5%), and 0 cases, respectively, in group A and 28 (26%), 3 (2.8%), and 1 (0.009%) case, respectively, in group B (P > 0.05). Conclusions The second puncture and injection technique may effectively increase the dispersion of cement, thus preventing recompression of the cemented vertebral body, and it does not increase the risk of cement leakage or adjacent vertebral fracture.

scholarly journals Outcomes of corticosteroid injection and percutaneous release in treatment of trigger finger at tertiary hospital of Eastern Nepal.

2021 ◽  
Vol 6 (2) ◽  
pp. 1449-1453
Author(s):  
Mithilesh Kumar Gupta ◽  
Ajay Chaudhary ◽  
Ajay Mahato
Keyword(s):  
Corticosteroid Injection ◽  
Tendon Sheath ◽  
Trigger Finger ◽  
Time Interval ◽  
Vas Score ◽  
Percutaneous Release ◽  
Intralesional Steroid ◽  
Group A ◽  
Group B

Introduction: Trigger finger or stenosing tenosynovitis is a common cause of painful fingers and thumb that result in painful triggering, snapping or locking of fingers on flexion and extension of involved digit. Available treatment options for this condition are NSAID, splints, intralesional steroid injection, percutaneous release and open release of tendon sheath. Objectives: To study the clinical and functional outcomes and complications of corticosteroid injection and percutaneous release in management of trigger finger. Methodology: In this prospective study, sixty patients who presented with Grade 2 to Grade 3 trigger finger were placed into two groups. Group A(30 patients) were treated with intralesional steroid (40 mg of methylprednisolone) injection. Group B (30 patients) underwent percutaneous surgical release of affected tendon sheath. Both group of patients were treated in outpatient department. Patients of both groups were then asked to follow on scheduled time interval of two-week, six-week, three-months and six-months of period and their progress were recorded. Results: The baseline VAS score before intervention in group A (5.82) and group B (6.12) was statistically significant. In group B there was significant improvement of VAS score till 6 months of follow up. However, in group A there was significant improvement of VAS score by 3 months of follow-up, but by end of 6 months it again raised to 2.14. Yet it was far better than baseline VAS score. Conclusion: In our study both corticosteroid injection and percutaneous trigger finger release were found to be much effective in management of trigger finger.

scholarly journals A Comparative Study on Efficacies of Posterior Microscopic Mini-open and Open Technique for Thoracolumbar Burst Fractures Accompanied With Severe Traumatic Spinal Stenosis

2021 ◽  
Author(s):  
Bin Zhang ◽  
Yanna Zhou ◽  
Hua Zou ◽  
Zimo Lu ◽  
Xin Wang ◽  
...  
Keyword(s):  
Cobb Angle ◽  
Spinal Stenosis ◽  
Spinal Canal ◽  
Thoracolumbar Burst Fractures ◽  
Canal Stenosis ◽  
Burst Fractures ◽  
Post Operation ◽  
Group A ◽  
Group B

Abstract Purpose To compare the efficacies of minimal invasive decompression by posterior microscopic mini-open technique combined with percutaneous pedicle fixation (hereafter MOT) and traditional open surgeries in patients with severe traumatic spinal canal stenosis resulting from AO Type A3 or A4 thoracolumbar burst fractures and provide references for clinical treatment. Methods The clinical materials of 133 patients with severe traumatic spinal canal stenosis caused by AO Type A3 or A4 thoracolumbar burst fractures who underwent MOT (group A) or traditional open surgery (group B) were retrospectively enrolled. The patient demographic and radiological data were analyzed between the two groups. Results A total of 64 patients were finally recruited in this study. There were no significant differences in gender, age, follow-up time, injury mechanism, injured level, Arbeitsgemeinschaft für Osteosynthesefragen (AO) classification, American Spinal Injury Association (ASIA) score, Visual analogue scale (VAS) score and hospital stay between the two groups (P>0.05). After procedures, the prevertebral height ratio (PHR), the Cobb angle, and the mid-sagittal canal diameter compression ratio (MSDCR) in two groups were significantly improved (P<0.05). Meanwhile, group A with little intraoperative bleeding volume, and the VAS score improved better at post-operation and last follow up, but the operative time was longer (P<0.05). The PHR, the Cobb angle in the two groups at the post-operation and last follow up without significantly different (P>0.05), the MSDCR was improved at last follow up when compared with the value at post-operation (P<0.05). However, the Cobb angle in group A was well maintained than in group B at last follow up (P<0.05) and the MSDCR in group B at last follow up improved better than in group A (P<0.05). Conclusions Both the MOT and traditional open surgery can treat AO type A3 and A4 thoracolumbar burst fractures accompanied with severe traumatic spinal stenosis effectively. The MOT has advantages including minimal invasion, extremely fine spinal canal decompression, lower intraoperative bleeding volume and obvious pain relief. We suggest that MOT should be preferentially selected for AO type A3 or A4 thoracolumbar burst fractures accompanied with severe traumatic spinal stenosis.

Long-term outcome of laminectomy for cervical ossification of the posterior longitudinal ligament

2013 ◽  
Vol 18 (5) ◽  
pp. 465-471 ◽  
Author(s):  
Soo Eon Lee ◽  
Chun Kee Chung ◽  
Tae-Ahn Jahng ◽  
Hyun-Jib Kim
Keyword(s):  
Recovery Rate ◽  
Statistical Significance ◽  
Japanese Orthopaedic Association ◽  
Posterior Longitudinal Ligament ◽  
Clinical Impression ◽  
Term Outcome ◽  
Long Term Outcome ◽  
The Mean

Object Although laminectomy is an effective surgical technique for the treatment of multilevel cervical stenotic lesions, postoperative kyphosis and neurological deterioration have been frequently reported after laminectomy. Hence, laminectomy without fusion is seldom performed nowadays. However, the clinical impression from the long-term follow-up of patients who had undergone laminectomy does not support that postoperative kyphosis is common in patients with ossification of the posterior longitudinal ligament (OPLL). In this paper, the authors assessed the long-term outcome of laminectomy for cervical OPLL in terms of the changes in the cervical curvature and in the neurological status. Methods The authors retrospectively reviewed medical records and radiological images in patients who had undergone cervical laminectomy between 1999 and 2009. The preoperative and the final follow-up status recovery rate were assessed using the Japanese Orthopaedic Association (JOA) scale. The cervical global angle and range of motion (ROM) were measured preoperatively and at the last follow-up. The cervical spine was classified into 3 types: lordotic, straight, and kyphotic. Results A total of 34 patients were available for medical record review and telephone interviews. There were 28 men and 6 women, whose mean age at the time of surgery was 57.8 years. The mean follow-up period was 57.5 months. The mean preoperative JOA score was 10.7, and the JOA score at the last follow-up was significantly improved to 14.3 (p < 0.001) with a recovery rate of 56.3%. The JOA score at each postoperative follow-up point increased until 6 years postoperatively; thereafter, it gradually decreased. The mean preoperative global angle was −11.3° and the most recent global angle was −8.4°. The preoperative ROM was 33.9° and the most recent ROM was 27.4°. There was no statistical significance in the change of cervical curvature or ROM. Preoperatively, 29 of the 34 patients had a lordotic cervical curvature and 5 patients had a straight spine. At last follow-up, 24 patients had a lordotic curvature, 3 patients changed from lordosis to kyphosis, and 7 patients had a straight spine. One patient whose cervical curvature changed from lordosis to kyphosis during the follow-up period underwent cervical fusion 9 years after the laminectomy procedure. Conclusions The long-term outcome of laminectomy for cervical OPLL is satisfactory in terms of the clinical and radiological aspects. The risk of postlaminectomy kyphosis was not high, raising the possibility that the OPLL itself may serve as a support for the spinal column.

Analysis of Clinical Results of Three Different Routes of Percutaneous Endoscopic Transforaminal Lumbar Discectomy for Lumbar Herniated Disk

2018 ◽  
Vol 1 (2) ◽  
pp. 8
Author(s):  
Farid Yudoyono ◽  
Rully Hanafi Dalan
Keyword(s):  
Analogue Scale ◽  
Clinical Results ◽  
Lumbar Discectomy ◽  
Excellent Outcome ◽  
Vas Score ◽  
Group A ◽  
Herniated Disk ◽  
The Mean ◽  
Group B

Objective: Percutaneous endoscopic transforaminal lumbar discectomy (PETLD) can be performed by using foraminal, intervertebral, and suprapedicular routes. The aim of this study was to assess clinical results of three different routes of PETLD.Methods: One hundred and eleven patients who underwent PETLD between January 2016 and October 2016 were included in this study. PETLD was performed using the foraminal (group A), intervertebral (group B), and suprapedicular (group C) routes in 32, 46, and 33 patients, respectively. Outcomes were evaluated using the visual analogue scale (VAS), Oswestry Disability Index (ODI), and MacNab criteria.Results: Seventy-one men and 40 were women (mean age 53.33 ± 14.12 years). The mean follow-up period was 6.44 ± 3.26 months. The preoperative VAS score decreased significantly (P < 0.01) in all 3 groups, but the postoperative VAS score was higher for the foraminal route than the intervertebral (P<0.001) and suprapedicular routes (P< 0.001). Excellent outcome grade according to MacNab criteria was less in foraminal route (18.7%) than in intervertebral (52.2%) and suprapedicular (56.7%) routes. ODI improved significantly (P< 0.01) in all 3 groups.Conclusion: All 3 routes of PETLD resulted in good to excellent clinical results. Nevertheless, the postoperative VAS score was higher for the foraminal route than the intervertebral and suprapedicular routes, probably because of the neurologic characteristics of the disk location. The surgeon should consider this problem to alleviate pain postoperatively and to better counsel the patient before surgery.

scholarly journals Analysis of progression of cervical OPLL using computerized tomography: typical sign of maturation of OPLL mass

2015 ◽  
Vol 23 (5) ◽  
pp. 539-543 ◽  
Author(s):  
Byung-Wan Choi ◽  
Dong-Hoon Baek ◽  
Lindsey C. Sheffler ◽  
Han Chang
Keyword(s):  
Vertebral Body ◽  
Mixed Type ◽  
Posterior Longitudinal Ligament ◽  
Younger Age ◽  
Show Evidence ◽  
Group A ◽  
The Mean ◽  
Multiple Levels ◽  
Group B

OBJECT The progression of cervical ossification of the posterior longitudinal ligament (OPLL) can lead to increase in the size of the OPLL mass and aggravation of neurological symptoms. In the present study, the authors aimed to analyze the progression of cervical OPLL by using CT imaging, elucidate the morphology of OPLL masses, and evaluate the factors associated with the progression of cervical OPLL. METHODS Sixty patients with cervical OPLL were included. All underwent an initial CT examination and had at least 24 months’ follow-up with CT. The mean duration of follow-up was 29.6 months. Fourteen patients (Group A) had CT evidence of OPLL progression, and 46 (Group B) did not show evidence of progression on CT. The 2 groups were compared with respect to the following variables: sex, age, number of involved segments, type of OPLL, and treatment methods. The CT findings, such as the connection of an OPLL mass with the vertebral body and formation of trabeculation in the mass, were evaluated. RESULTS Sex and treatment modality were not associated with OPLL progression. The mean age of the patients in Group A was significantly lower than that in Group B (p = 0.03). The mean number of involved segments was 5.3 in Group A and 3.6 in Group B (p = 0.002). Group A had a higher proportion of cases with the mixed type of OPLL, whereas Group B had a higher proportion of cases with the segmental type (p = 0.02). A connection between the vertebral body and OPLL mass and trabeculation formation were more common in Group B (p < 0.01). CONCLUSIONS Progression of cervical OPLL is associated with younger age, involvement of multiple levels, and mixed-type morphology. OPLL masses that are contiguous with the vertebral body and have trabecular formation are useful findings for identifying masses that are less likely to progress.

scholarly journals A comparison between remaining and resecting the posterior longitudinal ligament in percutaneous endoscopic transforaminal discectomy for disc herniation: A retrospective cohort study

2020 ◽  
Author(s):  
Wenhao Hu ◽  
Fanqi Hu ◽  
Chao Liu ◽  
Weibo Liu ◽  
Yi Jiang ◽  
...  
Keyword(s):  
Accurate Determination ◽  
Operation Time ◽  
Posterior Longitudinal Ligament ◽  
Surgical Methods ◽  
Significant Difference ◽  
Group A ◽  
Group B ◽  
Endoscopic Lumbar Discectomy ◽  
Surgical Duration

Abstract Background Nowadays, percutaneous endoscopic lumbar discectomy (PELD) has become a popular surgical option for the management of LDH, On the basis of the approach to the herniation disc materials, PELD could be classified into percutaneous endoscopic transforaminal discectomy (PETD) and percutaneous endoscopic interlaminar discectomy (PEID). During PETD procedure, especially in in-and-out approach, accurate determination of whether the posterior longitudinal ligament is needed resection seems particularly important.In the study, we tried assessing comparative clinical outcome, surgical duration and complications between the two different surgical methods of LDH treated by PETD via inside-and-out approach. Methods A total of 135 symptomatic LDH patients who were treated by PETD resecting the posterior longitudinal ligament (68 patients) or remaining the posterior longitudinal ligament (67 patients) during the surgery were included in the study. Visual analog scale (VAS) score, Oswestry disability index (ODI) and modified MacNab criteria were used to evaluate clinical outcomes. Operation time, blood loss, recurrence of LDH and other complication such as dural tear, nerve injury, intervertebral infection, etc. of these two groups were recorded. Clinical evaluation was performed preoperatively, immediately postoperatively, and at each follow-up visit (1 month, 3 months, and final follow-up). Results There were 38 males and 30 females in the group A that resecting the posterior longitudinal ligament (mean age = 52.40 ± 8.73 years) and 35 males and 32 females in the group B that remaining the posterior longitudinal ligament (mean age = 53.50 ± 9.24 years). The mean operation time of the group A and the group B respectively, were 82.7 ± 18.5 min and 115.6 ± 24.6 min (P < 0.01). The postoperative VAS scores and ODI were significantly higher than those before surgery in two groups (P < 0.01). The differences in the results were not significant between the two groups (P > 0.05). There was no significant difference in the complication rate, the excellent/good ratio and the recurrence rate between the two groups (P > 0.05). Conclusion Whether the posterior longitudinal ligament is resected do not make any difference on curative effect in PETD via inside-and-out approach, and remaining the ligament when it’s intact is preferred because of its shorter operation time.

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