STAR Ankle Component Fracture: Awareness, Not Alarm
OrthoBuzz occasionally receives posts from guest bloggers. In response to a recent “safety communication” from the FDA, the following commentary comes from Ariel Palanca, MD; Adam Bitterman, DO: and Christopher Gross, MD.
During the past decade, total ankle replacement (TAR) has been challenging the gold standard of ankle fusion for treatment of end-stage ankle arthritis. Improvements in TAR component design and refined surgical techniques have led to more predictable and reproducible outcomes.
On March 15, 2021, however, the US Food and Drug Administration (FDA) released a Safety Communication about the Scandinavian Total Ankle Replacement (STAR Ankle), a product line that DJO Surgical acquired from Stryker in November 2020. The FDA’s statement cites a “higher than expected” rate of fracture of the device’s mobile-bearing polyethylene component. The communication goes on to suggest that patients younger than 55 years old and those with an active lifestyle may have a higher risk of component fracture than older, more sedentary patients.
The STAR Ankle received premarket approval from the FDA in 2009, and the FDA is compiling data from 2 post-approval trials of the device. In August 2019, Stryker issued a safety notification regarding the higher-than-expected fracture risk for STAR polyethylene implanted before August 2014. The recent FDA safety notification states there may also be a high risk of fracture for STAR polyethylene components implanted after August 2014, although the agency’s notification acknowledges that “the long-term fracture rate is not known in devices manufactured after the 2014 packaging change.”
The “packaging change” mentioned above refers to the August 2014 changeover when STAR polyethylene started to be packaged in a foil pouch, which virtually eliminates oxidation of the polyethylene and should therefore reduce fracture rates. Additionally, many peer-reviewed journal articles have reported lower STAR-component fracture rates than those found in the post-approval trials at equal or longer follow-ups.
It’s also important to note that the 8-year follow-up FDA study that revealed a 13.8% cumulative polyethylene-fracture rate only included 87 of the 606 STAR patients in the clinical trial. Patients with complications are often more likely to follow up than those with no complications, creating a potential negative bias.
Still, to err on the side of caution, the FDA suggests that surgeons who treat and follow patients with a STAR implant closely monitor them–especially younger, more active patients–for potential component fractures until more post-approval data is analyzed to further clarify any risk.
Ariel Palanca, MD is an orthopaedic foot and ankle surgeon at Arch Health Medical Group in Escondido, California. Adam Bitterman, DO (@DrAdamBitterman) is a foot and ankle specialist, an assistant professor of orthopaedic surgery at Zucker School of Medicine at Hofstra/Northwell, and a member of the JBJS Social Media Advisory Board. Christopher Gross, MD is an orthopaedic surgeon specializing in foot and ankle disorders at the Medical University of South Carolina in Charleston and a member of the JBJS Social Media Advisory Board.
Outcomes of Joint-Preserving Surgery in RA-Affected Feet
Dramatic improvements in medical treatment of rheumatoid arthritis (RA) have led to marked reductions in joint damage and deformities. Consequently, surgical methods for treating RA-related foot problems have gradually evolved from joint-sacrificing to joint-preserving procedures. In a recent issue of The Journal of Bone & Joint Surgery, Yano et al. reported on outcomes of 105 feet in RA patients treated with joint-preserving methods followed up for a mean of 6 years.
What the Researchers Did:
- Performed a proximal rotational closing-wedge osteotomy of the first metatarsal and modified shortening oblique osteotomies of the lesser metatarsals
- Recorded Self-Administered Foot Evaluation Questionnaire (SAFE-Q) scores preoperatively and at latest follow-up
- Measured hallux valgus angle (HVA), intermetatarsal angle (IMA), and medial sesamoid position before surgery, 3 months after surgery, and at the latest follow-up
- Tracked delayed wound healing, hallux valgus recurrence, nonunion, and reoperations
- Calculated Kaplan-Meier survivorship with reoperation as the endpoint
What the Researchers Found:
- Surgery was associated with significantly improved median SAFE-Q scores, relative to preoperative values.
- The average HVA, IMA, and grade of medial sesamoid positioning decreased significantly, compared with preoperative measurements.
- Kaplan-Meier survivorship at 7 years was 89.5%.
- Delayed wound healing was found in 20% of the feet (all wounds healed with nonoperative treatment), hallux valgus recurrence in 10.5% of the feet, and reoperation in 10.5% of the feet.
Yano et al. emphasize several advantages of joint-sparing over joint-sacrificing surgery: preserved range of motion, stability of the metatarsophalangeal joint, and improved plantar-pressure distribution. However, these advantages and the “satisfactory” long-term outcomes noted above come with substantial complications that foot-and-ankle surgeons will strive to address in the future.
Surgical Costs: Just the Half of It
Total-cost breakdown for ankle-fracture patients treated nonoperatively.
The Journal is receiving an increasing number of manuscripts related to value assessments and cost-effectiveness analyses of treatments for orthopaedic pathologies. This line of investigation is crucial to helping the larger healthcare system lower costs while improving patient outcomes. One aspect of determining the total cost of a musculoskeletal intervention is the impact of so-called indirect costs. Components of indirect costs include lost patient wages from not working, higher transportation costs, and extra dollars spent by the individual or family to manage household chores and self-care.
In the December 16, 2020 issue of The Journal, Noback et al. examine the total, direct, and indirect costs of care among 60 patients with a lateral malleolar fracture that was treated either nonsurgically or surgically. They found that in many cases, indirect costs exceeded the direct cost of delivering medical/surgical care. Not surprisingly, this was especially true in nonoperatively treated patients, where three-quarters of the total cost were indirect costs (see Figure).
I believe that our community needs to more widely appreciate and study the impact of patients’ lost wage-earning opportunities and out-of-pocket expenditures. Every treatment recommendation we make in clinical practice involves these financial implications for our patients. Noback et al. go so far as to claim that “any cost-effectiveness analysis… must assess indirect costs or it risks drastically mischaracterizing a treatment’s value.”
We therefore should continue pushing our treatment and rehabilitation strategies to more aggressively limit time lost to full weight-bearing or use of the upper limb. Also, orthopaedic research should be directed toward strategies that limit the impact of indirect costs and family burdens as we seek to continuously improve care for our patients.
Marc Swiontkowski, MD
JBJS Editor-in-Chief
What Affects Symptoms in Kids with Flatfoot?
Pes planovalgus (flatfoot) is a common condition seen in the pediatric orthopaedic clinic. We who help manage this condition differentiate it from adult acquired flatfoot deformity, primarily in that most child and adolescent patients remain asymptomatic or minimally symptomatic and rarely require surgical intervention. However, it would be nice to have data to share with young patients and their parents regarding factors associated with flatfoot symptoms.
Min et al. provide some of that data in the September 2, 2020 issue of The Journal. The authors retrospectively evaluated factors affecting the symptoms of idiopathic pes planovalgus among 123 patients (mean age of 10.1 ± 3.2 years) using the 4-domain Oxford Ankle Foot Questionnaire (OxAFQ) administered to patients and their parents. They compared questionnaire scores to 3 radiographic measurements─anteroposterior (AP) talo-first metatarsal angle, lateral talo-first metatarsal angle, and hallux valgus angles. They also analyzed the scores in relation to patient age and sex.
Min et al. found that the physical domain score for the child-reported OxAFQ decreased by 0.74 with each 1° increase in the AP talo-first metatarsal angle. Because that angle is a surrogate for forefoot abduction, this finding portends worse patient-reported outcomes in kids with greater severity of that component of flatfoot. Female sex was also associated with lower physical domain scores, with the authors postulating that this might be attributable to culturally influenced sex differences.
In addition, age was a significant factor in 3 domains of the OxAFQ. Compared with scores from younger kids, children ≥10 years old and their parents reported statistically worse outcomes with regard to school/play, emotional well-being, and footwear. In other words, at or beyond the age of 10, flatfoot deformity seems to significantly affect the patient’s choice of footwear, interferes with the ability to participate in sports and play, and may cause personal distress, such as that which comes from being teased about foot appearance.
Orthopaedists can help manage most cases of pediatric flatfoot with sound footwear recommendations and reassurance. But it appears that in the setting of increased forefoot abduction, female sex, and symptoms that persist past the age of 10 years, further investigation may be warranted. Although this study has weaknesses, it shows that there may be detriments─both physical and emotional─associated with pes planovalgus in pediatric patients that should not be ignored.
Matthew R. Schmitz, MD
JBJS Deputy Editor for Social Media
What’s New in Orthopaedic Trauma 2020
Every month, JBJS publishes a review of the most pertinent and impactful studies published in the orthopaedic literature during the previous year in 13 subspecialties. Click here for a collection of OrthoBuzz summaries of these “What’s New” articles. This month, co-author Niloofar Dehghan, MD, selected the 5 most clinically compelling findings from the >20 studies summarized in the July 1, 2020 “What’s New in Orthopaedic Trauma.”
Hip Fracture
—An international randomized controlled trial (RCT) of hip fracture patients ≥45 years of age1 compared outcomes among 1,487 who underwent an “accelerated” surgical procedure (within 6 hours of diagnosis) and 1,483 who received “standard care” (surgery within 24 hours of diagnosis). Mortality and major complication percentages were similar in both groups, but it is important to note that even the standard-care group had a relatively rapid median time-to-surgery of 24 hours.
—An RCT of nearly 1,500 patients who were ≥50 years of age and followed for 2 years2 compared total hip arthroplasty (THA) with hemiarthroplasty for the treatment of displaced femoral neck fractures. There was no between-group difference in the need for secondary surgical procedures, but hip instability or dislocation occurred in 4.7% of the THA group versus 2.4% of the hemiarthroplasty group. Functional outcomes measured with the WOMAC index were slightly better (statistically, but not clinically) in the THA group. Serious adverse events were high in both groups (41.8% in the THA group and 36.7% in the hemiarthroplasty group). Although the authors conclude that the advantages of THA may not be as compelling as has been purported, THA’s benefits may become more pronounced with follow-up >2 years.
—A preplanned secondary analysis of data from the FAITH RCT examined the effect of posterior tilt on the need for subsequent arthroplasty among older patients with a Garden I or II femoral neck fracture who were treated with either a sliding hip screw or cannulated screws. Patients with a posterior tilt of ≥20° had a significantly higher risk of subsequent arthroplasty (22.4%) compared with those with a posterior tilt of <20° (11.9%). In light of these findings, instead of internal fixation, primary arthroplasty may be an appropriate treatment for older patients who have Garden I and II femoral neck fractures with posterior tilt of >20°.
Ankle Syndesmotic Injury
—An RCT that compared ankle syndesmosis fixation using a suture button with fixation using two 3.5-mm screws3 found a higher rate of malreduction at 3 months postoperatively with screw fixation (39%) than with suture button repair (15%). With the rate of reoperation also higher in the screw group due to implant removal, these findings add to the preponderance of recent evidence that the suture button technique is preferred.
Wound Management
—A 460-patient RCT examining the cost-effectiveness of negative-pressure wound therapy4 for initial wound management in severe open fractures of the lower extremity found the technique to be associated with higher costs and only marginal improvement in quality-adjusted life-years for patients.
References
- HIP ATTACK Investigators. Accelerated surgery versus standard care in hip fracture (HIP ATTACK): an international, randomised, controlled trial. Lancet.2020 Feb 29;395(10225):698-708. Epub 2020 Feb 9.
- Bhandari M, Einhorn TA, Guyatt G, Schemitsch EH, Zura RD, Sprague S, Frihagen F, Guerra-Farfán E, Kleinlugtenbelt YV, Poolman RW, Rangan A, Bzovsky S, Heels-Ansdell D, Thabane L, Walter SD, Devereaux PJ; HEALTH Investigators. Total hip arthroplasty or hemiarthroplasty for hip fracture. N Engl J Med.2019 Dec 5;381(23):2199-208. Epub 2019 Sep 26.
- Sanders D, Schneider P, Taylor M, Tieszer C, Lawendy AR; Canadian Orthopaedic Trauma Society. Improved reduction of the tibiofibular syndesmosis with TightRope compared with screw fixation: results of a randomized controlled study. J Orthop Trauma.2019 Nov;33(11):531-7.
- Petrou S, Parker B, Masters J, Achten J, Bruce J, Lamb SE, Parsons N, Costa ML; WOLLF Trial Collaborators. Cost-effectiveness of negative-pressure wound therapy in adults with severe open fractures of the lower limb: evidence from the WOLLF randomized controlled trial. Bone Joint J.2019 Nov;101-B(11):1392-401.
What’s New in Foot and Ankle Surgery 2020
Every month, JBJS publishes a review of the most pertinent and impactful studies published in the orthopaedic literature during the previous year in 13 subspecialties. Click here for a collection of OrthoBuzz summaries of these “What’s New” articles. This month, Matthew R. Schmitz, MD, JBJS Deputy Editor for Social Media, selected the 5 most clinically compelling findings from the >60 studies summarized in the May 20, 2020 “What’s New in Foot and Ankle Surgery.”
Total Ankle Replacement
—An analysis of a consecutive series of 278 total ankle replacemments1 found that the overall incidence of postoperative complications was 41.7%. However, the clinical outcome was affected in only 7.6% of these cases, as most complications were minor.
Syndesmotic Injuries
—A meta-analysis (total n = 397) found that functional outcomes and complications were similar after suture-button fixation and screw fixation for syndesmotic injuries.2 Time to full weight-bearing, however, was faster among patients receiving suture-button fixation.
Osteochondral Lesions of the Talus
—A prospective cohort study3 examined 101 patients with osteochondral talar lesions of <1.5 cm2. After a minimum follow-up of 36 months, patients treated with microfracture alone (n = 52) and patients treated with microfracture + autologous iliac crest bone marrow aspirate concentrate (BMAC) (n = 49) both reported significant improvement in pain, sport, and activities of daily living. The revision rate was significantly lower in the microfracture + BMAC cohort.
Plantar Fasciitis
—A randomized controlled trial4 compared stretching alone (n = 20) with stretching + proximal medial gastrocnemius recession (n = 20) in patients with >12 months of plantar heel pain. The operative group had significantly greater improvements in functional and pain scores and in forefoot plantar pressure at 12 months of follow-up. Achilles function and calf weakness were similar in both groups.
Clubfoot
—A retrospective case series reviewed 220 feet among 145 Nepalese children who had been treated for idiopathic clubfoot with the Ponseti method. At a minimum of 10 years of follow-up, 95% of the 220 feet achieved a plantigrade foot. Surgical treatment, typically a percutaneous Achilles tendon release, was required in 96% of the feet.
References
- Clough TM, Alvi F, Majeed H. Total ankle arthroplasty: what are the risks?: a guide to surgical consent and a review of the literature. Bone Joint J.2018 Oct;100-B(10):1352-8.
- Chen B, Chen C, Yang Z, Huang P, Dong H, Zeng Z. To compare the efficacy between fixation with tightrope and screw in the treatment of syndesmotic injuries: a meta-analysis. Foot Ankle Surg.2019 Feb;25(1):63-70. Epub 2017 Aug 18.
- Murphy EP, McGoldrick NP, Curtin M, Kearns SR. A prospective evaluation of bone marrow aspirate concentrate and microfracture in the treatment of osteochondral lesions of the talus. Foot Ankle Surg.2019 Aug;25(4):441-8. Epub 2018 Feb 22.
- Molund M, Husebye EE, Hellesnes J, Nilsen F, Hvaal K. Proximal medial gastrocnemius recession and stretching versus stretching as treatment of chronic plantar heel pain. Foot Ankle Int.2018 Dec;39(12):1423-31. Epub 2018 Aug 22.
Weight-Bearing CT: An Incremental Step in Addressing Posttraumatic Ankle Arthritis
Orthopaedic surgeons recognize that an intra-articular fracture of the distal tibia (pilon fracture) is the worst actor when it comes to the sequela of posttraumatic ankle osteoarthritis. Despite decades of focusing on surgical techniques that yield the best-looking postoperative radiographs, we have come to realize that, to reduce the risk of subsequent arthritis, limiting the extent of the surgical approach may be as important as achieving the “perfect” articular reduction. Slowly we have come to understand that articular cartilage damage from the injury (and in some instances exacerbated by overaggressive surgical dissection) is as big a factor as the bone injury in terms of postoperative joint-space narrowing and its associated ankle stiffness and pain.
Thankfully, the orthopaedic trauma community is making strides toward new biologic, mechanical, and rehabilitative interventions that have the potential to limit this articular narrowing. But to meaningfully evaluate the effectiveness of these strategies, we need not only validated patient-oriented functional outcome measures, but also more reliable and reproducible ways to assess the joint-space narrowing.
In the May 6, 2020 issue of The Journal, Willey et al. report on a standardized technique using weight-bearing computed tomography (WBCT), which yields a 3D assessment of the postoperative joint space with the ankle in a loaded, functional position (see Figure above). When this technique was applied to 20 patients (mean age of 44 years) with a partial or complete articular pilon fracture 6 months after surgical treatment, the authors found significantly less tibiotalar joint space in the injured ankle compared with the uninjured ankle. Interrater correlation and test-retest data indicated that this method has good measurement reliability and reproducibility.
Any safe, reliable, and reproducible measure of early joint-space narrowing after pilon fracture surgery is an important incremental step in designing clinical trials that will assess new interventions designed to preserve postoperative joint space—and hopefully reduce the incidence of posttraumatic ankle arthritis. Willey et al. have demonstrated the usefulness of WBCT as such a modality.
Marc Swiontkowski, MD
JBJS Editor-in-Chief
What’s New in Sports Medicine 2020
Every month, JBJS publishes a review of the most pertinent and impactful studies published in the orthopaedic literature during the previous year in 13 subspecialties. Click here for a collection of OrthoBuzz summaries of these “What’s New” articles. This month, co-author Christopher Y. Kweon, MD selected the 5 most clinically compelling findings from the 40 studies summarized in the April 15, 2020 “What’s New in Sports Medicine.”
ACL Graft Choice
—A randomized controlled trial (RCT) comparing bone-tendon-bone autograft, quadrupled hamstring tendon autograft, and double-bundle hamstring autograft for ACL reconstruction in young adults found the following:
- No between-group differences in patient-reported quality-of-life scores at 5 years
- Significantly higher rates of traumatic graft reinjuries in the hamstring-tendon and double-bundle groups
- Relatively low (37%) return to preinjury level of activity for the entire population, with no significant between-group differences
Meniscal Repairs with Bone Marrow Venting
—A double-blinded RCT1 of patients with complete, unstable, vertical meniscal tears compared isolated meniscal repair to meniscal repair with a bone marrow venting procedure (BMVP). Meniscal healing, as assessed with second-look arthroscopy at a mean of 35 weeks, was 100% in the BMVP group and 76% in the control group (p = 0.0035). Secondary pain and function measures at 32 to 51 months were also better in the BMVP group.
Rotator Cuff Repair Rehab
—A multisite RCT2 among >200 patients who received arthroscopic repair of a full-thickness rotator cuff tear compared standard rehabilitation (patients wore a sling at all times except when performing prescribed exercises) and early mobilization (patients wore a sling only when needed for comfort). Early mobilizers showed significantly better forward flexion and abduction at 6 weeks, but no subjective or objective differences (including retear rate) were found at any other time points.
Remplissage for Anterior Shoulder Instability
—A systematic review3 of studies investigating arthroscopic Bankart repair with and without remplissage found significantly higher instability-recurrence rates with isolated Bankart repair. Overall, the addition of remplissage appears to yield better patient-reported function scores compared with isolated Bankart repair alone.
Syndesmotic Ankle Injuries
—A meta-analysis of 7 RCTs (335 patients)4 comparing dynamic versus static fixation for syndesmotic injuries of the ankle found that the overall risk of complications was significantly lower in the dynamic fixation group. Reoperation rates were similar in the two groups, but implant breakage or loosening was reduced with dynamic fixation devices. Compared with static fixation, the dynamic fixation group also had higher AOFAS scores and lower VAS scores at various time points.
References
- Kaminski R, Kulinski K, Kozar-Kaminska K, Wasko MK, Langner M, Pomianowski S. Repair augmentation of unstable, complete vertical meniscal tears with bone marrow venting procedure: a prospective, randomized, double-blind, parallel-group, placebo-controlled study. Arthroscopy.2019 May;35(5):1500-1508.e1. Epub 2019 Mar 20.
- Sheps DM, Silveira A, Beaupre L, Styles-Tripp F, Balyk R, Lalani A, Glasgow R, Bergman J, Bouliane M; Shoulder and Upper Extremity Research Group of Edmonton (SURGE). Early active motion versus sling immobilization after arthroscopic rotator cuff repair: a randomized controlled trial. Arthroscopy.2019 Mar;35(3):749-760.e2.
- Lazarides AL, Duchman KR, Ledbetter L, Riboh JC, Garrigues GE. Arthroscopic remplissage for anterior shoulder instability: a systematic review of clinical and biomechanical studies. Arthroscopy.2019 Feb;35(2):617-28. Epub 2019 Jan 3.
- Grassi A, Samuelsson K, D’Hooghe P, Romagnoli M, Mosca M, Zaffagnini S, Amendola A. Dynamic stabilization of syndesmosis injuries reduces complications and reoperations as compared with screw fixation: a meta-analysis of randomized controlled trials. Am J Sports Med.2019 Jun 12. [Epub ahead of print].
Treating Transitional Ankle Fractures: Best Evidence Yet
Transitional fractures of the ankle in adolescents are related to torsional injuries that occur around the time that the distal tibial physis begins to close. In recent years, treatment has moved toward screw fixation when the intra-articular fracture gap in Salter type III (Tillaux) and type IV (triplane) fractures is between 1 mm and 2 mm. The rationale for operative treatment has been that intra-articular fracture gaps should be completely reduced, particularly in younger patients, to limit the long-term risk of post-traumatic osteoarthroses. However, evidence supporting the wisdom of surgical intervention has been thin at best. (See Clinical Summary on Triplane Ankle Fractures.)
In the April 15, 2020 issue of The Journal, Lurie et al. report on a retrospective analysis of 34 patients with a triplane fracture and 23 patients with a Tillaux fracture, all of which had 2 mm to 5 mm of articular displacement. Among those 57 patients, 34 were treated with surgery and 23 with closed reduction and casting.
Based on regression analysis, nonoperative treatment, a larger intra-articular gap after closed reduction, and the presence of a grade-III complication were associated with worse functional outcomes at a mean follow-up of 4.5 years. Patients who were treated nonoperatively and had a gap ≤2.5 mm had significantly better functional scores than similar patients with a gap >2.5 mm. From this data, the authors conclude that “surgical management of these injuries likely conveys the greatest functional benefit when the intra-articular gap exceeds 2.5 mm.”
This study has the usual issues of treatment and detection bias inherent in retrospective reviews, and the measurement of fracture gaps, even with the CT scans these authors used, is not always reliable at this level of precision. Nevertheless, this data from Lurie et al. is the best we have to date to indicate that the so-called “2-mm rule” of nonoperative management of transitional ankle-fracture gaps ≤2 mm probably makes sense in most clinical situations.
Marc Swiontkowski, MD
JBJS Editor-in-Chief
Subtalar Joint Compensation after Ankle Fusion
Ankle fusion continues to be a predictable treatment for degenerative tibiotalar arthritis. It improves both pain and function from primary osteoarthritis and degeneration related to chronic instability or trauma. JBJS has published several recent studies demonstrating that the outcomes of fusion compare favorably with those of total ankle replacement, particularly in higher-demand patients. (See, for example, Effectiveness and Safety of Ankle Arthrodesis Versus Arthroplasty and Outcomes of Total Ankle Replacement, Arthroscopic Ankle Arthrodesis, and Open Ankle Arthrodesis for Isolated Non-Deformed End-Stage Ankle Arthritis.)
Many clinicians have wondered why outcomes after ankle arthrodesis are typically so much better than those after arthrodesis of other mobile joints. In the April 1, 2020 issue of The Journal, Lenz et al. provide an answer. Using dual fluoroscopy integrated with 3-D CT, the authors compared the subtalar motion of the surgically fused ankle in 10 patients with the motion of the untreated, asymptomatic side. The findings strongly suggest that compensatory increased plantar flexion of the subtalar joint allows improved function following successful arthrodesis. The authors found that this increased motion occurred during both normal plantigrade ambulation and bilateral heel raises.
Clinicians can use this important information to explain to patients who are deciding between ankle arthrodesis and arthroplasty how fusion can not only improve pain, but can also result in good functional range of motion. On the other hand, the authors surmise that the compensatory increase in subtalar joint plantar flexion may explain the reported increased risk of future subtalar osteoarthritis in surgically fused ankles. However, to answer that question, we’ll need larger, longitudinal clinical studies that evaluate the relationship between the compensatory post-fusion subtalar kinematics discovered by Lenz et al. and radiographic findings and patient-reported pain and function.
Marc Swiontkowski, MD
JBJS Editor-in-Chief
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