Clinical and Radiological Outcomes Comparing Percutaneous Chevron-Akin Osteotomies vs Open Scarf-Akin Osteotomies for Hallux Valgus

2017 ◽  
Vol 39 (3) ◽  
pp. 311-317 ◽  
Author(s):  
Mun Chun Lai ◽  
Inderjeet Singh Rikhraj ◽  
Yew Lok Woo ◽  
William Yeo ◽  
Yung Chuan Sean Ng ◽  
...  
Keyword(s):  
Hallux Valgus ◽  
Short Form ◽  
Perioperative Period ◽  
Tertiary Hospital ◽  
Wound Complications ◽  
Percutaneous Technique ◽  
Level Of Evidence ◽  
Valgus Angle ◽  
American Orthopaedic

Background: Minimally invasive surgeries have gained popularity due to less soft tissue trauma and better wound healing. To date, limited studies have compared the outcomes of percutaneous and open osteotomies. This study aims to investigate the clinical and radiological outcomes of percutaneous chevron-Akin osteotomies vs open scarf–Akin osteotomies at 24-month follow-up. Method: We reviewed a prospectively collected database in a tertiary hospital hallux valgus registry. Twenty-nine feet that underwent a percutaneous technique were matched to 58 feet that underwent open scarf and Akin osteotomies. Clinical outcome measures assessed included visual analog scale (VAS) scores, American Orthopaedic Foot & Ankle Society Hallux Metatarsophalangeal-Interphalangeal score (AOFAS Hallux MTP-IP), and Short Form 36 (SF-36) Health Survey. Radiological outcomes included hallux valgus angle (HVA) and intermetatarsal angle (IMA). All patients were prospectively followed up at 6 and 24 months. Results: Both groups showed comparable clinical and radiological outcomes at the 24-month follow-up. However, the percutaneous group demonstrated less pain in the perioperative period ( P < .001). There were significant differences in the change in HVA between the groups but comparable radiological outcomes in IMA at the 24-month follow-up. The percutaneous group demonstrated shorter length of operation ( P < .001). There were no complications in the percutaneous group but 3 wound complications in the open group. Conclusions: We conclude that clinical and radiological outcomes of third-generation percutaneous chevron-Akin osteotomies were comparable with open scarf and Akin osteotomies at 24 months but with significantly less perioperative pain, shorter length of operation, and less risk of wound complications. Level of Evidence: Level III, retrospective comparative series.

Percutaneous Triple and Double Osteotomies for the Treatment of Hallux Valgus

2016 ◽  
Vol 38 (2) ◽  
pp. 159-166 ◽  
Author(s):  
Rodrigo Díaz Fernández
Keyword(s):  
Hallux Valgus ◽  
Case Series ◽  
Wound Complications ◽  
Percutaneous Technique ◽  
Retrospective Case ◽  
Level Of Evidence ◽  
Minimal Incision ◽  
Valgus Angle ◽  
Before And After ◽  
American Orthopaedic

Background: Percutaneous surgery to correct deformities of the forefoot presents the advantages of using a minimal incision, which involves less soft tissue damage and less risk of wound complications. For severe deformities, percutaneous techniques have not been proven as effective. We propose a technique for the treatment of severe hallux valgus. Methods: In a sample of 52 feet operated on 48 patients, we performed a double percutaneous osteotomy (closure proximal osteotomy and a distal Akin) or triple when a Reverdin-Isham osteotomy was added. We measured preoperatively the American Orthopaedic Foot & Ankle Society (AOFAS) score at the 1-year and 2-year follow-up, as well as the values of hallux valgus angle (HVA), intermetatarsal angle (IMA), distal metatarsal articular ankle (DMAA), and shortening and elevation of the first metatarsal. The presence of metatarsalgia was recorded before and after the surgery. Results: HVA, IMA, and DMAA improved from 39.3 ± 7.1, 17.0 ± 2.0, and 16 ± 8.7 to 11.2 ± 6.2, 8.4 ± 3.4, and 8.3 ± 6.2, respectively. In 5 cases (10%), there was an elevation of the distal metatarsal bone, but only in 2 cases did a transfer metatarsalgia develop. There were no significant correlations between the amount of shortening and the presence of postoperative metatarsalgia. Scores on the AOFAS scale improved from 47.6 ± 5.6 to 89.7 ± 10.1 points. Conclusion: The results are comparable to those reported with other more established techniques. Transfer metatarsalgia did not correlate with lifting or shortening of the metatarsal. We indicate the percutaneous technique for IMA above 15 degrees and increased DMAA or congruent joints. Level of Evidence: Level IV, retrospective case series.

scholarly journals Surgical treatment of hallux valgus using a modified Reverdin-Isham technique

2021 ◽  
Vol 15 (1) ◽  
pp. 49-53
Author(s):  
Luiz Lara ◽  
Lúcio Torres Filho ◽  
Gabriel Cervone ◽  
Juan Grajales ◽  
Glaucia Bordignon ◽  
...  
Keyword(s):  
Surgical Treatment ◽  
Hallux Valgus ◽  
Case Series ◽  
Metatarsal Head ◽  
Level Of Evidence ◽  
Valgus Angle ◽  
Significant Correction ◽  
The Mean ◽  
American Orthopaedic

Objective: To evaluate the postoperative results of patients who underwent surgical treatment of hallux valgus with a modified Reverdin-Isham (RI) technique and to compare the achieved correction with that reported by studies using the original technique. Methods: This is a retrospective study with patients with mild to moderate hallux valgus who underwent surgery from June 2010 to July 2019. All patients were operated using the modified RI technique. Data were collected through the American Orthopaedic Foot and Ankle Society (AOFAS) questionnaire, in addition to pre and postoperative radiographic studies of the intermetatarsal angle (IMA), the hallux valgus angle (HVA), and the distal metatarsal articular angle (DMAA). Results: The mean postoperative follow-up was 30.1 months, and the mean age of patients was 56.4 years. The median AOFAS score in the postoperative period was increased by 56 points. The mean HVA was reduced in 16.5°, the mean IMA was reduced in 4.3°, and the mean DMAA was reduced in 10°. There were no cases of displacement or deviation of the first metatarsal head during the postoperative follow-up. Conclusion: The modified RI technique provided considerable stability to the osteotomy, in addition to a significant correction of the measured angles and an improvement in AOFAS scores, demonstrating itself as an effective technique for correcting mild to moderate hallux valgus. Level of Evidence IV, Therapeutic Studies, Case Series.

Results of Scarf Osteotomy Without Implant Fixation in the Treatment of Hallux Valgus

2018 ◽  
Vol 39 (11) ◽  
pp. 1320-1327 ◽  
Author(s):  
Henryk Liszka ◽  
Artur Gądek
Keyword(s):  
Hallux Valgus ◽  
Cost Effective ◽  
Implant Fixation ◽  
Level Of Evidence ◽  
Scarf Osteotomy ◽  
Valgus Angle ◽  
Duration Of Surgery ◽  
American Orthopaedic ◽  
Retrospective Comparative Study

Background: The main goal of the study was to evaluate the costs, clinical and radiologic results, and complications of hallux valgus surgery using scarf osteotomy, depending on the type of fixation (with or without screws). Methods: We evaluated 169 patients who underwent scarf osteotomy between January 2013 and August 2016. The patients were separated into 3 groups depending on the type of stabilization: A, 2 screws (50 patients); B, modified with 1 screw (55 patients); C, modified without implant (64 patients). We assessed duration of surgery, additional procedures, pre- and postoperative hallux valgus angle (HVA) and intermetatarsal angle (IMA) on anteroposterior and lateral foot weightbearing radiographs, the American Orthopaedic Foot & Ankle Society (AOFAS) hallux-metatarsophalangeal-interphalangeal scale for the clinical assessment preoperatively and at the 12-month follow-up. We recorded all the complications and compared the costs between the groups. Results: Both the average HVA (A: from 33.7 to 12.6 degrees, B: 35.0 to 13.2 degrees, C: 34.7 to 12.4 degrees) and IMA (A: from 14.9 to 7.5 degrees, B: 15.2 to 6.9 degrees, C: 15.5 to 7.8 degrees) decreased in all groups without significant intergroup differences. The average AOFAS score improved in all the groups (A: from 40 to 88 points, B: 38 to 89 points, C: 42 to 91 points). A similar complication rate was observed (A: 9%, B: 10%, C: 11%). In group C, we noted a shorter time of surgery, and the procedure was the most cost-effective. Conclusion: Scarf osteotomy without implant stabilization was faster and cost-effective and gave comparable results. It was technically demanding and required patient compliance. Level of Evidence: Level III, retrospective comparative study.

scholarly journals Percutaneous surgical treatment of hallux valgus

2020 ◽  
Vol 14 (3) ◽  
pp. 278-284
Author(s):  
Luiz Lara ◽  
Lúcio Torres Filho ◽  
Gabriel Cervone ◽  
Rafael Viana ◽  
Glaucia Bordignon ◽  
...  
Keyword(s):  
Hallux Valgus ◽  
Case Series ◽  
Metatarsal Bone ◽  
Level Of Evidence ◽  
First Metatarsal ◽  
Valgus Angle ◽  
Angle Correction ◽  
Age At Surgery ◽  
American Orthopaedic

Objective: To analyze outcomes of hallux valgus surgical correction using the Reverdin-Isham technique by means of clinical and radiographic studies. Methods: We retrospectively assessed 43 feet (38 patients) with moderate to severe hallux valgus treated from June 2009 to July 2014. Mean age at surgery was 59 years; mean postoperative follow-up time was 79 months. Patients were assessed at pre- and postoperative periods both functionally, by the American Orthopaedic Foot and Ankle Society (AOFAS) score, and radiographically, by the hallux valgus angle (HVA), intermetatarsal angle (IMA), distal metatarsal articular angle (DMAA), and shortening of 1st metatarsal bone. Results: AOFAS scores had a mean increase of 55 points. Mean HVA decreased 14.5°, whereas IMA and DMAA exhibited a mean decrease of 3.8° and 9.7°, respectively. Mean shortening of the first metatarsal bone was 3mm. Conclusion: The presented surgical technique showed to be effective to correct mild to moderate hallux valgus, resulting in appropriate angle correction angular and significant increase in AOFAS scores. Level of Evidence IV; Therapeutic Studies; Case Series.

Multicenter Early Radiographic Outcomes of Triplanar Tarsometatarsal Arthrodesis With Early Weightbearing

2019 ◽  
Vol 40 (8) ◽  
pp. 955-960 ◽  
Author(s):  
Justin J. Ray ◽  
Jennifer Koay ◽  
Paul D. Dayton ◽  
Daniel J. Hatch ◽  
Bret Smith ◽  
...  
Keyword(s):  
Hallux Valgus ◽  
Case Series ◽  
Retrospective Case ◽  
Recurrence Rates ◽  
Level Of Evidence ◽  
Radiographic Outcomes ◽  
Valgus Angle ◽  
First Ray ◽  
Akin Osteotomy

Background:Hallux valgus is a multiplanar deformity of the first ray. Traditional correction methods prioritize the transverse plane, a potential factor resulting in high recurrence rates. Triplanar first tarsometatarsal (TMT) arthrodesis uses a multiplanar approach to correct hallux valgus in all 3 anatomical planes at the apex of the deformity. The purpose of this study was to investigate early radiographic outcomes and complications of triplanar first TMT arthrodesis with early weightbearing.Methods:Radiographs and charts were retrospectively reviewed for 57 patients (62 feet) aged 39.7 ± 18.9 years undergoing triplanar first TMT arthrodesis at 4 institutions between 2015 and 2017. Patients were allowed early full weightbearing in a boot walker. Postoperative radiographs were compared with preoperative radiographs for hallux valgus angle (HVA), intermetatarsal angle (IMA), tibial sesamoid position (TSP), and lateral round sign. Any complications were recorded.Results:Radiographic results demonstrated significant improvements in IMA (13.6 ± 2.7 degrees to 6.6 ± 1.9 degrees), HVA (24.2 ± 9.3 degrees to 9.7 ± 5.1 degrees), and TSP (5.0 ± 1.3 to 1.9 ± 0.9) from preoperative to final follow-up ( P < .001). Lateral round sign was present in 2 of 62 feet (3.2%) at final follow-up compared with 52 of 62 feet (83.9%) preoperatively. At final follow-up, recurrence was 3.2% (2/62 feet), and the symptomatic nonunion rate was 1.6% (1/62 feet). Two patients required hardware removal, and 2 patients required additional Akin osteotomy.Conclusion:Early radiographic outcomes of triplanar first TMT arthrodesis with early weightbearing were promising with low recurrence rates and maintenance of correction.Level of Evidence:Level IV, retrospective case series.

Comparison of Intermediate-term Outcomes of Total Ankle Arthroplasty in Primary and Ligamentous Post-traumatic Osteoarthritis

2019 ◽  
Vol 40 (11) ◽  
pp. 1273-1281 ◽  
Author(s):  
Gun-Woo Lee ◽  
Asep Santoso ◽  
Keun-Bae Lee
Keyword(s):  
Short Form ◽  
Total Ankle Arthroplasty ◽  
Level Of Evidence ◽  
Ankle Arthroplasty ◽  
Radiographic Outcomes ◽  
Primary Osteoarthritis ◽  
Post Traumatic ◽  
American Orthopaedic ◽  
End Stage

Background: Ankle ligamentous injuries without fracture can result in end-stage ligamentous post-traumatic osteoarthritis, which may cause ligamentous imbalance after total ankle arthroplasty (TAA). However, outcomes of TAA in these patients are not well known. The purpose of this study was to evaluate intermediate-term clinical and radiographic outcomes of TAA in patients with ligamentous post-traumatic osteoarthritis and compare them with results of TAA for patients with primary osteoarthritis. Methods: We enrolled 114 patients (119 ankles) with consecutive primary TAA using HINTEGRA prosthesis at a mean follow-up duration of 6.0 years (range, 3-13). We divided all patients into 2 groups according to the etiology of osteoarthritis: (1) primary osteoarthritis group (69 ankles) and (2) ligamentous post-traumatic osteoarthritis group (50 ankles). Results: There was no significant intergroup difference in mean Ankle Osteoarthritis Scale (AOS), American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot score, Short Form-36 Physical Component Summary, visual analog scale pain score, ankle range of motion, or complications at the final follow-up. However, the final tibiotalar angle was less corrected to 4.2 degrees in the ligamentous post-traumatic osteoarthritis group compared to 2.7 degrees in the primary osteoarthritis group ( P = .001). More concomitant procedures were required at the index surgery for the ligamentous post-traumatic osteoarthritis group ( P = .001). The estimated 5-year survivorship was 93.4% (primary osteoarthritis group: 91.3%; ligamentous post-traumatic osteoarthritis group: 95.8%). Conclusions: Clinical outcomes, complication rate, and 5-year survivorship of TAA in ankles with primary and ligamentous post-traumatic osteoarthritis were comparable with intermediate-term follow-up. Our results suggest that TAA would be a reliable treatment in ankles with ligamentous post-traumatic osteoarthritis when neutrally aligned stable ankles are achieved postoperatively. Level of Evidence: Level III, retrospective cohort study.

Pes Planus Deformity and Its Association With Hallux Valgus Recurrence Following Scarf Osteotomy

2020 ◽  
Vol 41 (10) ◽  
pp. 1212-1218
Author(s):  
Gavin John Heyes ◽  
Amir R. Vosoughi ◽  
Lizzy Weigelt ◽  
Lyndon Mason ◽  
Andrew Molloy
Keyword(s):  
Hallux Valgus ◽  
P Value ◽  
Level Of Evidence ◽  
Pes Planus ◽  
First Metatarsal ◽  
Scarf Osteotomy ◽  
Metatarsal Angle ◽  
Valgus Angle ◽  
Akin Osteotomy

Background: Hallux valgus recurrence is an unsatisfactory complication, with many causes postulated. This study investigated the effect of pes planus on recurrence after scarf osteotomy. Methods: A total of 183 feet were retrospectively reviewed. All patients were treated with a scarf osteotomy and if required Akin osteotomy. We measured preoperative lateral talus first metatarsal angle (T1MA) to study pes planus; an angle of under −4 degrees was considered pes planus. We measured pre and postoperative hallux valgus angle (HVA), intermetatarsal angle (IMA), and sesamoid location. In total 164 feet were suitable for inclusion, with follow-up of at least 6 months (10 males and 154 females, mean age: 52 years). Results: Recurrence frequency (HVA greater than 15 degrees) was 27 feet (16%). Hallux valgus recurrence was not influenced by gender ( P value = .66) or preoperative IMA ( P value = .48). Preoperative HVA greater than 35 degrees was associated with increased frequency of recurrence ( P value = .004). Those with T1MA less than −10 degrees demonstrated progression in HVA and deterioration in sesamoid location up to 6 months postoperatively ( P value = .038). HVA did not progress beyond 6 months. The prevalence of recurrent hallux valgus with normal T1MA was 1%, in T1MA −4 to −10 degrees it was 29% and in T1MA less than −10 degrees it was 47% ( P value <.001). Breaks in T1MA less than −4 degrees were found at the naviculocuneiform joint in 68% of feet in this series. Conclusion: The prevalence of hallux valgus recurrence correlated with the severity of pes planus. Level of Evidence: Level III, retrospective cohort study.

Effect of Bipartite Hallucal Sesamoid on Hallux Valgus Surgery

2017 ◽  
Vol 38 (6) ◽  
pp. 634-640 ◽  
Author(s):  
Young Hwan Park ◽  
Chan Dong Jeong ◽  
Gi Won Choi ◽  
Hak Jun Kim
Keyword(s):  
Hallux Valgus ◽  
Study Cohort ◽  
Aofas Score ◽  
Level Of Evidence ◽  
Radiographic Outcomes ◽  
Chevron Osteotomy ◽  
Radiographic Measurements ◽  
Valgus Angle ◽  
Retrospective Comparative Study

Background: Bipartite hallucal sesamoids are often found in patients with hallux valgus. However, it is unknown whether bipartite hallucal sesamoids affect the results of hallux valgus surgery or not. The purpose of the present study was to evaluate the outcomes of chevron osteotomy for hallux valgus with and without bipartite hallucal sesamoid. Methods: A total of 152 patients (168 feet) treated with distal or proximal chevron osteotomy for hallux valgus constituted the study cohort. The 168 feet were divided into 2 groups: bipartite hallucal sesamoid (31 feet) and without bipartite hallucal sesamoid (137 feet). Hallux valgus angle (HVA), intermetatarsal angle (IMA), distal metatarsal articular angle (DMAA), tibial sesamoid position, and first metatarsal length were measured for radiographic outcomes and the American Orthopaedic Foot & Ankle Society (AOFAS) hallux metatarsophalangeal-interphalangeal (MTP-IP) score was measured for clinical outcomes. Results: All radiographic measurements and the AOFAS score showed significant ( P < .05) improvement at the time of final follow-up compared with preoperative measurements in both groups. No significant differences ( P > .05) were found between the 2 groups in terms of HVA, IMA, DMAA, tibial sesamoid position, metatarsal shortening, and AOFAS score on final follow-up. Conclusions: This study suggests that bipartite hallucal sesamoids do not affect the results of hallux valgus surgery. Level of Evidence: Level III, retrospective comparative study.

Effect of Severity of Deformity on Clinical Outcomes of Scarf Osteotomies

2020 ◽  
Vol 41 (6) ◽  
pp. 705-713 ◽  
Author(s):  
Gin Way Law ◽  
Kae Sian Tay ◽  
Jeremy Wei Sern Lim ◽  
Karen Ting Zhang ◽  
Chusheng Seng ◽  
...  
Keyword(s):  
Patient Satisfaction ◽  
Clinical Outcomes ◽  
Hallux Valgus ◽  
Short Form ◽  
Group Differences ◽  
Level Of Evidence ◽  
Severe Group ◽  
American Orthopaedic ◽  
The Impact ◽  
Second Toe

Background: Literature is sparse on whether severity of hallux valgus affects outcomes of surgery. We thus aimed to evaluate the impact of hallux valgus severity on the clinical outcomes of surgery. Methods: 83 consecutive scarf osteotomies performed by a single surgeon for symptomatic hallux valgus between 2007 and 2011 were divided into 3 groups (mild, moderate, and severe) based on severity of their preoperative hallux valgus using the hallux valgus and intermetatarsal angles. Outcomes were assessed using the visual analog scale (VAS) for pain, 36-Item Short Form Health Survey physical functioning (SFPF) and mental health (SFMH) subscales, and American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot scores. These were assessed preoperatively and at 6 months and 2 years postoperatively. Patient satisfaction was assessed at 6 months and 2 years postoperatively. Eleven (13.2%), 54 (65.1%), and 18 (21.7%) feet were in the mild, moderate, and severe groups, respectively. Results: There was no difference in preoperative VAS, SFPF, SFMH and AOFAS scores between the groups except for AOFAS scores for the second toe, which were poorer with increasing hallux valgus. Postoperatively, there was improvement across all outcome scores. VAS and AOFAS showed excellent scores, and patient satisfaction was high across all 3 groups (88.9%, 89.4%, and 86.7%). The severe group had slightly lower SFPF scores at 6 months (mild, 81.1; moderate, 84.0; severe, 74.3; P = .031) and 2 years postoperatively (mild, 93.4; moderate, 89.7; severe, 76.4; P = .005), and slightly poorer second toe scores for VAS (mild, 0.0; moderate, 0.1; severe, 1.2; P = .017) and AOFAS (mild, 94.7; moderate, 93.5; severe, 83.4; P = .043) at 2 years postoperatively. All other scores including patient satisfaction showed no between-group differences. Complication and revision rates between the groups were similar. Conclusion: Surgery for symptomatic hallux valgus lead to excellent outcomes and high patient satisfaction regardless of severity of deformity. Level of Evidence: Level III, comparative series.

scholarly journals Percutaneous Chevron Osteotomy Combined with Adductor Tendon Release for Hallux Valgus Correction

2019 ◽  
Vol 4 (4) ◽  
pp. 2473011419S0013
Author(s):  
Sofia Carlucci ◽  
Nelly Carrasco ◽  
Maria Santini-Araujo ◽  
Ana Parise ◽  
Leonardo Conti ◽  
...  
Keyword(s):  
Minimally Invasive ◽  
Hallux Valgus ◽  
Deformity Correction ◽  
Hallux Valgus Angle ◽  
Chevron Osteotomy ◽  
Metatarsal Angle ◽  
Valgus Angle ◽  
Akin Osteotomy ◽  
American Orthopaedic

Category: Bunion, Midfoot/Forefoot Introduction/Purpose: The use of minimally invasive techniques for hallux valgus may provide complete deformity correction with minor soft tissue damage, which reduces morbidity and shortens recovery. In this way, some open osteotomies were adapted to percutaneous approaches, with good outcomes reported. The minimally invasive chevron-Akin (MICA) described by Vernois and Redfern in 2011, combines benefits of percutaneous approaches with a stable internal fixation. Since 2015 we have adapted this technique, by adding a percutaneous adductor tenotomy to dispense with the Akin osteotomy. The aim of this study was to report a single surgeon series of consecutive patients with moderate hallux valgus managed with a minimally invasive chevron osteotomy and a percutaneous adductor tendon release. Methods: This was a prospective cohort study. A total of 38 feet with moderate hallux valgus underwent the procedure and were followed up for a minimum 12 months (SD 1.10). The median age was 58 years (IQR 52 - 65), 36 women and 2 men. Radiological parameters were compared at preoperatory and at the last follow-up and included: Hallux Valgus Angle (HVA), Inter- Metatarsal Angle (IMA), Distal Metatarsal Articular Angle (DMAA) and first metatarsal shortening. Time to consolidation was also assessed. For clinical evaluation the American Orthopaedic Foot & Ankle Society score (AOFAS) was evaluated. Complications during the follow up were reported. Patients in which another procedure in the hallux was performed, with previous surgeries or not completed 1 year follow-up were excluded. Results: Radiologic postoperative parameters demonstrated to achieved correction. At the last follow up there was a statistically significant decrease in the hallux valgus angle, the intermetatarsal angle and distal metatarsal articular angle. Shortening of the first metatarsus was a mean 7.02 mm (IQR 1.24 - 10,27). The mean AOFAS score increased from 58.23 (SD 9.02) pre-operatively to 97.15 (SD 4.72) post-operatively (p< 0.001). Complications reported were 2 superficial infections, 1 broken screw, 1 screw extraction. Five patients referred metatarsalgia after surgery and 1 presented a fourth metatarsal stress fracture. Only one patient presented lost of correction in the first postoperative week and needed a second surgery. Conclusion: Our series of hallux valgus correction with a minimally invasive chevron osteotomy combined with the adductor tendon release shows good clinical and radiological outcomes, and results are comparable to series with the additional Akin osteotomy. Comparative studies are needed for major evidence.

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