scholarly journals Occupational Outcomes and Revision Rates for Medial Unicondylar Knee Arthroplasty in U.S. Military Servicemembers

2021 ◽  
Author(s):  
Marina Rodriguez ◽  
Ken Heida ◽  
Danielle E. Rider ◽  
Gens P. Goodman ◽  
Brian R. Waterman ◽  
...  
Keyword(s):  
Return To Work ◽  
Knee Arthroplasty ◽  
Military Service ◽  
Revision Rate ◽  
Perioperative Complications ◽  
Case Series ◽  
Unicondylar Knee Arthroplasty ◽  
Level Of Evidence ◽  
Medial Unicondylar Knee Arthroplasty

AbstractThis study evaluates return to work and revision rates for medial unicondylar knee arthroplasty (UKA) in a high-demand military cohort. Patient demographic and clinical variables were isolated from the medical records of active-duty military servicemembers with at least 2 years of postoperative follow-up and correlated with return to work, medial UKA survivorship, and perioperative complications. The medial UKA annual revision rate was calculated as the percentage of implants revised per observed component year. A total of 39 servicemembers underwent 46 primary medial UKAs (32 unilateral and 7 bilateral) with a mean follow-up of 3.9 (2.0–6.6) years. At a minimum of 2 years postoperatively, 33 (85%) servicemembers returned to military service or successfully completed their service obligation. Older servicemembers (odds ratio [OR] = 0.67; 95% confidence interval [CI]: 0.45, 0.99) had a significantly decreased OR for knee-related medical separation. Nine servicemembers (20%) had conversion to TKA at an average of 2.4 (range, 0.6–5.6) years with a medial UKA annual revision rate of 5%. When compared with Navy/Air Force, Army/Marine servicemembers had an increased TKA conversion rate (OR = 5.40; 95% CI: 1.13, 25.81). Older age decreased the likelihood of medical separation and Army/Marines service was the sole risk factor associated with conversion to TKA. The level of evidence is IV, therapeutic case series.

Intermediate-term Experience With the STAR Total Ankle in the United States

2018 ◽  
Vol 40 (3) ◽  
pp. 268-275 ◽  
Author(s):  
Evan M. Loewy ◽  
Thomas H. Sanders ◽  
Arthur K. Walling
Keyword(s):  
United States ◽  
Perioperative Complications ◽  
Case Series ◽  
Major Complication ◽  
The United States ◽  
Complication Rates ◽  
Level Of Evidence ◽  
Patient Reported ◽  
The Mean

Background: Limited intermediate and no real long-term follow-up data have been published for total ankle arthroplasty (TAA) in the United States. This is a report of clinical follow-up data of a prospective, consecutive cohort of patients who underwent TAA by a single surgeon from 1999 to 2013 with the Scandinavian Total Ankle Replacement (STAR) prosthesis. Methods: Patients undergoing TAA at a single US institution were enrolled into a prospective study. These patients were followed at regular intervals with history, physical examination, and radiographs; American Orthopaedic Foot & Ankle Society (AOFAS) Ankle-Hindfoot Scale scores were obtained and recorded. Primary outcomes included implant survivability and functional outcomes scores. Secondary outcomes included perioperative complications such as periprosthetic or polyethylene fracture. Between 1999 and 2013, a total of 138 STAR TAAs were performed in 131 patients; 81 patients were female. The mean age at surgery was 61.5 ± 12.3 years (range, 30-88 years). The mean duration of follow-up for living patients who retained both initial components at final follow-up was 8.8±4.3 years (range 2-16.9 years). Results: The mean change in AOFAS Ankle-Hindfoot scores from preoperative to final follow-up was 36.0 ± 16.8 ( P < .0001). There were 21 (15.2%) implant failures that occurred at a mean 4.9 ± 4.5 years postoperation. Ten polyethylene components in 9 TAAs (6.5%) required replacement for fracture at an average 8.9 ± 3.3 years postoperatively. Fourteen patients died with their initial implants in place. Conclusion: This cohort of patients with true intermediate follow-up after TAA with the STAR prosthesis had acceptable implant survival, maintenance of improved patient-reported outcome scores, and low major complication rates. Level of Evidence: Level IV, case series.

Osteochondral Allograft Transplantation of the Knee in Patients Aged 40 Years and Older

2017 ◽  
Vol 46 (3) ◽  
pp. 581-589 ◽  
Author(s):  
Dean Wang ◽  
Vivek Kalia ◽  
Claire D. Eliasberg ◽  
Tim Wang ◽  
Francesca R. Coxe ◽  
...  
Keyword(s):  
Knee Arthroplasty ◽  
Rating Scale ◽  
Short Form ◽  
Case Series ◽  
Hazard Ratio ◽  
Osteochondral Allograft ◽  
Cartilage Defects ◽  
Level Of Evidence ◽  
Allograft Transplantation

Background: Treatment of large chondral defects of the knee among patients aged ≥40 years remains a difficult clinical challenge owing to preexisting joint degeneration and the lack of treatment options short of arthroplasty. Purpose: To characterize the survivorship, predictors of failure, and clinical outcomes of osteochondral allograft transplantation (OCA) of the knee among patients aged ≥40 years. Study Design: Case series; Level of evidence, 4. Methods: Prospectively collected data were reviewed for 54 consecutive patients aged ≥40 years who were treated with OCA. Preoperative levels of osteoarthritis (according to Kellgren-Lawrence classification) and meniscal volume and quality were graded from review of radiographs and magnetic resonance imaging. Complications, reoperations, and patient responses to validated outcome measures were reviewed. A minimum follow-up of 2 years was required for analysis. Failure was defined by any removal or revision of the allograft or conversion to arthroplasty. Results: Among 51 patients (mean age, 48 years; range, 40-63 years; 65% male), a total of 52 knees had symptomatic focal cartilage lesions (up to 2 affected areas) that were classified as Outerbridge grade 4 at the time of OCA and did not involve substantial bone loss requiring shell allografts or additional bone grafting. Mean duration of follow-up was 3.6 years (range, 2-11 years). After OCA, 21 knees (40%) underwent reoperation, including 14 failures (27%) consisting of revision OCA (n = 1), unicompartmental knee arthroplasty (n = 5), and total knee arthroplasty (n = 8). Mean time to failure was 33 months, and 2- and 4-year survivorship rates were 88% and 73%, respectively. Male sex (hazard ratio = 4.18, 95% CI = 1.12-27.13) and a higher number of previous ipsilateral knee operations (hazard ratio = 1.70 per increase in 1 surgical procedure, 95% CI = 1.03-2.83) were predictors of failure. A higher Kellgren-Lawrence osteoarthritis grade on preoperative radiographs was associated with higher failure rates in the Kaplan-Meier analysis but not the multivariate model. At final follow-up, clinically significant improvements were noted in the pain (mean score, 47.8 to 67.6) and physical functioning (56.8 to 79.1) subscales of the Short Form-36, as well as the International Knee Documentation Committee subjective form (45.0 to 63.6), Knee Outcome Survey–Activities of Daily Living (64.5 to 80.1), and overall condition statement (4.5 to 6.8) ( P < .001). No significant changes were noted for the Marx Activity Rating Scale (5.1 to 3.9, P = .789). Conclusion: A higher failure rate was found in this series of patients aged ≥40 years who were treated with OCA as compared with other studies of younger populations. However, for select older patients, OCA can be a good midterm treatment option for cartilage defects of the knee.

scholarly journals Return to Work After Pectoralis Major Repair

2021 ◽  
Vol 9 (12) ◽  
pp. 232596712110456
Author(s):  
Avinesh Agarwalla ◽  
Anirudh K. Gowd ◽  
Joseph N. Liu ◽  
Grant H. Garcia ◽  
Gregory P. Nicholson ◽  
...  
Keyword(s):  
Return To Work ◽  
Case Series ◽  
Pectoralis Major ◽  
Workers Compensation ◽  
Level Of Evidence ◽  
Major Repair ◽  
Intensity Information ◽  
Patient Consultation ◽  
Light Medium

Background: Pectoralis major repair (PMR) is an infrequent injury that occurs during resistance training, most commonly during the eccentric phase of muscle contraction. As the incidence of weight training continues to increase, it is important to understand the outcomes after PMR. Purpose: To evaluate the rate and duration of return to work in patients undergoing PMR. Study Design: Case series; Level of evidence, 4. Methods: Consecutive patients undergoing PMR from 2010 to 2016 at a single institution were retrospectively reviewed at a minimum of 1 year postoperatively. Patients completed a standardized and validated work questionnaire, as well as a visual analog scale for pain, American Shoulder and Elbow Surgeons survey, Single Assessment Numerical Evaluation, and a satisfaction survey. Results: Of the 60 eligible patients who had a PMR, 49 (81.7%) were contacted at the final follow-up. Of the 49 patients, 46 (93.9%) had been employed within 3 years before surgery (mean ± SD age, 40.4 ± 8.2 years; follow-up, 3.9 ± 2.8 years). Of these, 45 (97.8%) returned to work by 1.6 ± 2.1 months postoperatively, and 41 (89.1%) returned to the same level of occupational intensity. Patients who held sedentary, light-, medium-, or high-intensity occupations returned to work at a rate of 100.0%, 100.0%, 83.3%, and 66.7% by 0.8 ± 1.0, 0.8 ± 1.0, 1.3 ± 2.7, and 3.3 ± 2.7 months, respectively. Five of 6 patients (83.3%) with workers’ compensation returned to their previous occupations by 5.0 ± 1.6 months, while 100% of those without workers’ compensation returned to work by 1.1 ± 1.7 months ( P < .001). Overall, 44 patients (95.7%) were satisfied with the procedure, and 40 (87.0%) would have the operation again if presented the opportunity. A single patient (2.2%) required revision PMR. Conclusion: Approximately 98% of patients who underwent PMR returned to work by 1.6 ± 2.1 months postoperatively. Patients with higher-intensity occupations took longer to return to their preoperative levels of occupational intensity. Information regarding return to work is imperative in preoperative patient consultation to manage expectations.

scholarly journals UNICOMPARTIMENTAL KNEE ARTHROPLASTY - 15 YEARS FOLLOW UP

2020 ◽  
Vol 28 (5) ◽  
pp. 233-235
Author(s):  
GILBERTO LUIS CAMANHO
Keyword(s):  
Knee Arthroplasty ◽  
Unicompartmental Knee Arthroplasty ◽  
Case Series ◽  
Level Of Evidence ◽  
Unicompartmental Knee ◽  
Long Term Follow Up ◽  
Lost To Follow Up ◽  
Knee Arthroplasty Surgery ◽  
Arthroplasty Surgery

ABSTRACT Objective: To evaluate clinically and radiologically the long-term follow-up of patients with anteromedial osteoarthritis who underwent unicompartmental knee arthroplasty surgery. Methods: This study included 36 patients who underwent unicompartmental knee arthroplasty surgery for medial compartmental osteoarthritis with a minimum of 15-year post-operative follow-up. All surgeries were performed by a single surgeon (G.L.C) using the Miller-Galante unicompartmental knee implant. Patients were analyzed regarding their clinical functional and implant radiographic conditions. Results: From the 46 patients who could have completed 15 years of follow-up, three required revision surgery with conversion to total knee arthroplasty (6.5%), 36 completed the 15-year follow-up period, and the others were lost to follow-up for reasons not related to unicompartmental arthroplasty. Conclusion: In these 36 patients, the result was satisfactory after follow-up, with complaints and sign of progression of osteoarthritis in some cases. Level of Evidence IV, Case series.

scholarly journals Increased Early Revision Rate With the INFINITY Total Ankle Prosthesis

2018 ◽  
Vol 40 (1) ◽  
pp. 9-17 ◽  
Author(s):  
Elizabeth A. Cody ◽  
Michel A. Taylor ◽  
James A. Nunley ◽  
Selene G. Parekh ◽  
James K. DeOrio
Keyword(s):  
Tibial Component ◽  
Revision Rate ◽  
Case Series ◽  
Total Ankle Arthroplasty ◽  
Secondary Outcome ◽  
Level Of Evidence ◽  
Ankle Arthroplasty ◽  
Early Revision ◽  
Component Loosening

Background: A number of new 2-component total ankle arthroplasty systems that emphasize minimal bone resection have been introduced for which few clinical outcomes reports are available. Our aim was to identify the rate of early revision among patients receiving the 2-component INFINITY prosthesis. Methods: Patients from 2 prospectively collected databases at the authors’ institution were screened for inclusion in the present study. All patients who underwent a primary total ankle arthroplasty (TAA) with the INFINITY prosthesis and who were at least 1 year postoperative were included. A total of 159 ankles with a mean 20 months of follow up (range, 12-37) met these criteria. All surgeries were performed by 1 of 2 orthopedic foot and ankle surgeons with extensive experience in TAA. The primary outcome was the need for revision surgery, defined as removal of 1 or both metal components. Peri-implant lucency at most recent follow-up was a secondary outcome. Weightbearing radiographs at most recent follow-up were graded for lucency independently by 2 reviewers. Results: Sixteen ankles (10%) underwent revision at a mean 13 months postoperatively. The most common reasons for revision were symptomatic tibial component loosening and deep infection (6 patients each, 3.8%). Of the 108 ankles with retained components and at least 1 year of radiographic follow-up, 8 (7.4%) had global lucency around the tibial component suggestive of loosening at most recent follow-up. Conclusions: Our initial review of patients undergoing TAA with this new 2-component prosthesis demonstrates an elevated early revision rate due to tibial component loosening compared to other implant systems. Level of Evidence: Level IV, case series.

scholarly journals Are Trabecular Metal Cones a Valid Option to Treat Metaphyseal Bone Defects in Complex Primary and Revision Knee Arthroplasty?

Joints ◽  
2017 ◽  
Vol 06 (01) ◽  
pp. 058-064 ◽  
Author(s):  
Tommaso Bonanzinga ◽  
Thorsten Gehrke ◽  
Akos Zahar ◽  
Stefano Zaffagnini ◽  
Maurilio Marcacci ◽  
...  
Keyword(s):  
Infection Rate ◽  
Clinical Data ◽  
Knee Arthroplasty ◽  
Case Reports ◽  
Case Series ◽  
Bone Defects ◽  
Trabecular Metal ◽  
Level Of Evidence ◽  
Metaphyseal Bone

Purpose Metaphyseal bone defects are a challenge in complex primary and revision total knee arthroplasty (TKA). Recently, several studies have been published with promising results about the use of Trabecular Metal (TM) cones to address bone defects. The aim of this study is to review the literature to assess the efficacy of TM cones to address metaphyseal bone loss. Methods A comprehensive search was performed on PubMed, Medline, CINAHL, Cochrane, Embase, and Google Scholar databases using various combinations of the following keywords: “metaphyseal,” “cones,” “tantalum,” “knee,” and “revision.” Only papers reporting clinical data about the use of trabecular metal cones were included in the analysis. In vitro studies, case reports, surgical technique, or other studies where it was not possible to collect clinical data were excluded. Patients characteristics, details of the surgical procedures, outcome, and complications were collected from each included study. Results No controlled studies were available in the literature and all the papers were case series. In 16 studies included, the records of 442 patients with 447 implants and 523 TM cones were reported. The mean follow-up was 42 months (range: 5–105) for 360 procedures. Among 437 procedures, 30.4% were septic revisions. The Anderson Orthopaedic Research Institute (AORI) classification was available for 352 defects: 13 type 1, 69 type 2A, 115 type 2B, and 155 type 3. To manage these 352 defects, 360 TM cones were implanted. Intraoperative fractures occurred 13 times (10 femoral/3 tibial), 6 required surgical fixation. The overall infection rate was 7.38%, and the infection rate for the aseptic procedures was 0.99%. An aseptic exchange was performed 13 times, among these procedures two TM cones were loose. Signs of loosening were found just in 1.3% of the 523 TM cones implanted (5 femoral/2 tibial) during 447 procedures. Conclusion The TM cones are an effective solution to manage bone defects in complex primary and revision TKA at intermediate follow-up. The incidence of complications was low; however, the femoral metaphysis proved to be more susceptible to complications. Level of Evidence Level IV, systematic review of level IV studies.

scholarly journals Keeping It in the Fairway

2018 ◽  
Vol 3 (3) ◽  
pp. 247301141879009
Author(s):  
Michel A. Taylor ◽  
James R. Lachman ◽  
Samuel B. Adams ◽  
James A. Nunley ◽  
James K. DeOrio
Keyword(s):  
Knee Arthroplasty ◽  
Case Series ◽  
Level Of Evidence ◽  
Postoperative Function ◽  
Institutional Review ◽  
Significant Difference ◽  
High Level ◽  
End Stage ◽  
Operating Surgeon

Background: Total ankle arthroplasty (TAA) provides a surgical alternative to tibiotalar arthrodesis when treating end-stage ankle arthritis. TAA preserves range of motion at the tibiotalar joint leading to improved postoperative function. Many patients who undergo TAA wish to maintain a high level of activity, including participation in low-impact sports such as golf. There are several studies in the total hip and total knee arthroplasty literature that have looked at the effect of total joint arthroplasty on golf handicap. We hypothesized that similar to hip and knee arthroplasty research, TAA is likely to result in a postoperative increase in golf handicap. Methods: After obtaining institutional review board approval, we retrospectively identified 60 patients (from 140 consecutive TAAs performed between August 2016 and February 2017) who had undergone TAA, played golf pre- and postoperatively, and had at least 1 year of postoperative follow-up. The average postoperative follow-up for the cohort was 28.1 months. Variables including preoperative and postoperative golf handicaps, swing laterality, age, gender, surgical laterality, implant used, and operating surgeon were recorded. Results: The average preoperative and postoperative handicaps were 19.7 and 17.9, respectively, which did not represent a statistically significant difference ( P = .07). Patients who played 3 or more rounds per week had better preoperative and postoperative handicaps compared to patients who played 2 rounds or less; however, the change in their handicap following TAA and the number of rounds played per week was not affected. There was no association between the change in handicap and the follow-up period, handedness of golf shot, surgical laterality, implant used, or the operating surgeon. Conclusion: Our findings showed that golf handicap was not negatively affected following TAA in this series. Level of Evidence: Level IV, case series.

scholarly journals Locked fracture dislocations of the proximal humerus: postoperative results and a proposed modification of the classification

2021 ◽  
Author(s):  
Jonas Schmalzl ◽  
Annika Graf ◽  
Fabian Gilbert ◽  
Michael Kimmeyer ◽  
Christian Gerhardt ◽  
...  
Keyword(s):  
Glenohumeral Joint ◽  
Revision Rate ◽  
Constant Score ◽  
Treatment Options ◽  
Case Series ◽  
Retrospective Case ◽  
Level Of Evidence ◽  
Choice Of Treatment ◽  
The Mean

Abstract Background Locked dislocations of the glenohumeral joint are disabling and often painful conditions and the treatment is challenging. This study evaluates the functional outcome and the different prosthetic treatment options for chronic locked dislocations of the glenohumeral joint and a subclassification is proposed. Methods In this single-center retrospective case series, all patients with a chronic locked dislocation treated surgically during a four-year period were analyzed. Constant score (CS), Quick Disabilities of Shoulder and Hand Score (DASH), patient satisfaction (subjective shoulder value (SSV)), revision rate and glenoid notching were analyzed. Results 26 patients presented a chronic locked dislocation of the glenohumeral joint. 16 patients (62%) with a mean age of 75 [61–83] years were available for follow-up at 24 ± 18 months. CS improved significantly from 10 ± 6 points to 58 ± 21 points (p < 0.0001). At the final follow-up, the mean DASH was 27 ± 23 and the mean SSV was 58 ± 23 points. The complication rate was 19% and the revision rate was 6%; implant survival was 94%. Scapular notching occurred in 2 (13%) cases (all grade 1). Conclusion With good preoperative planning and by using the adequate surgical technique, good clinical short-term results with a low revision rate can be achieved. The authors suggest extending the Boileau classification for fracture sequelae type 2 and recommend using a modified classification to facilitate the choice of treatment as the suggested classification system includes locked posterior and anterior dislocations with and without glenoid bone loss. Level of evidence: IV.

scholarly journals Minimum 10-Year Clinical Outcome of Lateral Collagen Meniscal Implants for the Replacement of Partial Lateral Meniscal Defects: Further Results From a Prospective Multicenter Study

2021 ◽  
Vol 9 (5) ◽  
pp. 232596712199491
Author(s):  
Alberto Grassi ◽  
Gian Andrea Lucidi ◽  
Giuseppe Filardo ◽  
Piero Agostinone ◽  
Luca Macchiarola ◽  
...  
Keyword(s):  
Survival Rate ◽  
Case Series ◽  
Final Analysis ◽  
Activity Level ◽  
Long Term Results ◽  
Level Of Evidence ◽  
Unicompartmental Knee Arthroplasties ◽  
Tegner Score

Background: The collagen meniscal implant (CMI) is a biologic scaffold aimed at replacing partial meniscal defects. The long-term results of lateral meniscal replacement have never been investigated. Purpose: To document the clinical outcomes and failures of lateral CMI implantation for partial lateral meniscal defect at a minimum 10-year follow-up. Study Design: Case series; Level of evidence, 4, Methods: This study included 24 consecutive patients who underwent lateral CMI implantation for partial lateral meniscal defects between April 2006 and September 2009 and who were part of a previous study with a 2-year follow-up. Outcome measures at the latest follow-up included the Lysholm score, Knee injury and Osteoarthritis Outcome Score, visual analog scale (VAS) for pain, Tegner activity level, and EuroQol 5-Dimensions score. Data regarding complications and failures were collected, and patients were asked about their satisfaction with the procedure. Results: Included in the final analysis were 19 patients (16 male, 3 female) with a mean age at surgery of 37.1 ± 12.6 years and a mean follow-up of 12.4 ± 1.5 years (range, 10-14 years). Five failures (26%) were reported: 1 CMI removal because of implant breakage and 4 joint replacements (2 unicompartmental knee arthroplasties and 2 total knee arthroplasties). The implant survival rate was 96% at 2 years, 85% at 5 years, 85% at 10 years, 77% at 12 years, and 64% at 14 years. Lysholm scores at the final follow-up were rated as “excellent” in 36% (5 of 14 nonfailures), “good” in 43% (6 of 14), and “fair” in 21% (3 of 14). The VAS score was 3.1 ± 3.1, with only 16% (3 of 19 patients) reporting that they were pain-free; the median Tegner score was 3 (interquartile range, 2-5). All clinical scores decreased from the 2-year follow-up; however, with the exception of the Tegner score, they remained significantly higher compared with the preoperative status. Overall, 79% of patients were willing to undergo the same procedure. Conclusion: Lateral CMI implantation for partial lateral meniscal defects provided good long-term results, with a 10-year survival rate of 85% and a 14-year survival rate of 64%. At the final follow-up, 58% of the patients had “good” or “excellent” Lysholm scores. However, there was a general decrease in outcome scores between the short- and the long-term follow-up.

scholarly journals Failed Surgery for Patellar Tendinopathy in Athletes: Midterm Results of Further Surgical Management

2021 ◽  
Vol 9 (3) ◽  
pp. 232596712199455
Author(s):  
Nicola Maffulli ◽  
Francesco Oliva ◽  
Gayle D. Maffulli ◽  
Filippo Migliorini
Keyword(s):  
Surgical Management ◽  
Revision Surgery ◽  
Case Series ◽  
Sports Participation ◽  
Patellar Tendinopathy ◽  
Symptom Duration ◽  
Level Of Evidence ◽  
Training Time ◽  
The Mean

Background: Tendon injuries are commonly seen in sports medicine practice. Many elite players involved in high-impact activities develop patellar tendinopathy (PT) symptoms. Of them, a small percentage will develop refractory PT and need to undergo surgery. In some of these patients, surgery does not resolve these symptoms. Purpose: To report the clinical results in a cohort of athletes who underwent further surgery after failure of primary surgery for PT. Study Design: Case series; Level of evidence, 4. Methods: A total of 22 athletes who had undergone revision surgery for failed surgical management of PT were enrolled in the present study. Symptom severity was assessed through the Victorian Institute of Sport Assessment Scale for Patellar Tendinopathy (VISA-P) upon admission and at the final follow-up. Time to return to training, time to return to competition, and complications were also recorded. Results: The mean age of the athletes was 25.4 years, and the mean symptom duration from the index intervention was 15.3 months. At a mean follow-up of 30.0 ± 4.9 months, the VISA-P score improved 27.8 points ( P < .0001). The patients returned to training within a mean of 9.2 months. Fifteen patients (68.2%) returned to competition within a mean of 11.6 months. Of these 15 patients, a further 2 had decreased their performance, and 2 more had abandoned sports participation by the final follow-up. The overall rate of complications was 18.2%. One patient (4.5%) had a further revision procedure. Conclusion: Revision surgery was feasible and effective in patients in whom PT symptoms persisted after previous surgery for PT, achieving a statistically significant and clinically relevant improvement of the VISA-P score as well as an acceptable rate of return to sport at a follow-up of 30 months.

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