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Ryssman, Daniel B.

Mayo Clinic

Mayo Clinic

Citations 8

Case Study in Education: Improving Resident Didactic Training
Charles, Rohan , Turner, Lindsey E , Cole, Channon E Cordes, Barlow, Jonathan D. , Ryssman, Daniel, Vlasak, M.D. Alexander, Turner, Norman S. , Cordes Cole, Channon E, Vlasak, Alexander , Barlow, Jonathan D , Ryssman, Daniel B., Vlasak, Alexander

JBJS Open Access | August 18, 2026 | Volume: 11 | Issue: 3 | Pages: No page available

10.2106/jbjs.oa.26.00095 Get It

Introduction: Flipped classroom models, which use active, case-based discussion, have shown promise across graduate medical education. Previous literature demonstrates that transitioning to a flipped classroom model resulted in significant increases in overall Orthopaedic In-Training Examination (OITE) scores. This observational study retrospectively compares foot and ankle OITE scores for orthopaedic surgery residents before and after implementation of a flipped classroom curriculum. Methods: This retrospective study reviewed OITE scores for orthopaedic residents, comparing a lecture-based curriculum (n = 49) to a flipped classroom curriculum (n = 61). Residents who started their second year in July 2020 or later were defined as treated. The curriculum is given to the postgraduate year-2 (PGY2) residents only. Percentage of correct foot and ankle questions (F&A) were analyzed via mixed-effects models using random-subject intercepts. Fixed effects included PGY, overall performance on other sections, and flipped classroom status. All statistical analyses were performed in R version 4.4.1. Results: Residents in the flipped classroom cohort demonstrated a statistically significant increase in F&A questions answered correctly. The average increase was 7% (95% confidence interval: 4%, 10%; p < 0.001). This improvement trend became clearly visible in PGY3 and grew stronger in senior residents. Specifically, PGY3 residents improved their mean percentage correct from 62.26% to 66.07% (p = 0.16). PGY4 residents improved from 69.16% to 74.83% (p = 0.013), and PGY5 residents improved from 69.03% to 75.53% (p = 0.006). Historically, approximately 75% of traditional PGY5 residents scored lower on the F&A section than on the rest of the examination. Conversely, in the flipped classroom group, approximately 75% of PGY4 and PGY5 residents scored higher on the F&A section compared with other sections Discussion: The implementation of a flipped classroom model was associated with a statistically significant improvement in resident performance on the F&A section of the OITE. The educational benefits of this curriculum appear cumulative over the course of residency, with the most substantial performance gains realized by senior residents in their fourth and fifth years of training. Level of Evidence: Level III , Observational Study. See Instructions for Authors for a complete description of levels of evidence.
Association of Complication Rates and Severe Obesity in Patients Undergoing Ankle Arthrodesis
Kuttner, Nicolas P. , Owen, Aaron R. , Ryssman, Daniel B., Kitaoka, Harold B. , Turner, Norman S.

Foot & Ankle International | November 29, 2024 | Volume: 46 | Issue: 2 | Pages: 210-216

10.1177/10711007241300327 Get It

Background: Tibiotalar arthrodesis (TTA) is a common operation for end-stage ankle arthritis. Elevated body mass index (BMI) is believed to contribute to complications following TTA. Previous studies involved national registries or small, underpowered cohorts. This study aimed to determine the effects of elevated BMI on nonunion and complication rates following TTA with a large cohort from a single academic institution. Methods: A retrospective study identified 514 patients (527 ankles) who underwent primary TTA from 2005-2017. Mean age was 60 years. Patients were stratified by BMI according to the World Health Organization classification. A reference group of 203 patients (208 ankles) included normal weight or mildly overweight patients (BMI 18.5 to <30). Ankle radiographs were evaluated to determine union or nonunion. Other outcomes included revision TTA, reoperations, subsequent adjacent joint arthrodesis, infection, and readmission. Data were analyzed using Pearson χ 2 and odds ratios for categorical variables. Analysis of variance and Kaplan-Meier estimation assessed continuous variables and time-to-event outcomes, respectively. Mean follow-up was 34.3 months. Results: Obesity class III patients had elevated risk of complications compared with normal weight patients including nonunion (odds ratio [OR] 3.96, P = .002), revision (OR 3.69, P = .03), superficial infection (OR 9.36, P = .002), and readmission (OR 10.90, P = .01). Superficial infection rates were elevated in class I (OR 6.36, P = .007) and readmissions in class II (OR 9.98, P = .01). No differences were found in reoperation ( P = .448), symptomatic implant removal ( P = .805), adjacent joint arthrodesis ( P = .353), or deep infection ( P = .507) rates. Discussion: In this retrospective review after TTA, increased rates of nonunion, revision, superficial infection, and readmission were found in obesity class III patients, compared with the reference group of normal weight or mildly overweight patients. Superficial infection rates were likewise relatively elevated in class I and readmission rates in class II patients.
Combined Surgical Technique of Hyperselective and Partial Motor Neurectomies for Spastic Equinus, Equinovarus, and Claw Toe Deformities
Wu, Kitty Y. , Pino, Paula A. , Ryssman, Daniel B., Rhee, Peter C.

Plastic and Reconstructive Surgery - Global Open | November 12, 2024 | Volume: 12 | Issue: 11 | Pages: e6207

10.1097/gox.0000000000006207 Get It

Background: Patients with spastic equinus, equinovarus, and claw toe deformities can experience marked pain and functional limitations in the ability to weight-bear comfortably, ambulate efficiently, or mobilize independently. Seen in 80% of patients with cerebral palsy and 18% of patients with stroke (1, 2), the spastic foot and ankle deformities, and its secondary sequelae of static joint contractures, osseous changes, and chronic pain, are unfortunately common. Methods: Adult and pediatric patients undergoing combined hyperselective and selective partial motor neurectomies for varus or claw toe deformities were reviewed. Patient demographics and complications were recorded. Pre- and postoperative Modified Ashworth Scale scores were compared. Results: Twenty-three patients (16 adults and seven pediatric) met inclusion criteria and were included in analysis. At early 6-month follow-up, the mean preoperative Modified Ashworth Score of 2.8 in adult patients and 3.0 in pediatric patients decreased to 0.6 postoperatively. Complications in three adult patients included one patient with temporary dysesthesias to the plantar foot, one with a popliteal abscess requiring incision and drainage, and one superficial wound dehiscence that was managed conservatively. Conclusions: A combined technique of hyperselective and partial motor neurectomies are effective in decreasing tone in the correction of spastic foot and ankle deformities in both adult and pediatric patients in short-term 6-month follow-up.
Outcomes Following Treatment of the Infected Achilles Tendon
Bowers, Mark , Turner, Norman S. , Ryssman, Daniel B., Moran, Steven L. , Bowers, Mark W

Foot & Ankle Orthopaedics | June 12, 2019 | Volume: 4 | Issue: 2 | Pages: No page available

10.1177/2473011419846943 Get It

Background: Infection following Achilles tendon surgery is a devastating complication and can be difficult to treat and often leads to poor outcomes. A number of treatments have been described, but there is little information concerning outcomes of these treatments. Our purpose was to evaluate the clinical and functional outcomes of patients who have undergone treatment for an infected Achilles tendon after acute and chronic midsubstance repair. Methods: We retrospectively reviewed the medical records of 20 patients who had undergone surgical treatment for an infected Achilles tendon between 2000 and 2016. The mean follow-up time was 21 months (range, 2-68 months). All patients underwent extensive debridement of the tendon with removal of all infected tissue and foreign material. Soft tissue wound coverage was utilized for large wounds that were not amenable to primary or secondary closure. All patients received culture-specific intravenous (IV) antibiotics for 3 to 6 weeks. Postoperatively, the extremity was immobilized in a splint followed by a cast until the wound was healed. The cast was then replaced with a walking boot and the patients were provided a physical therapy program. Functional outcomes were measured using the Foot and Ankle Ability Measure (FAAM) Activity of Daily Living (ADL) scale. Results: All wounds had healed at the time of last follow-up. Three patients (15%) required an unplanned return to the operating room for repeat debridement. All patients were able to walk without the use of a gait aid. Five patients (25%) required continued use of a boot or brace during ambulation. Fourteen patients participated in the FAAM ADL survey. There were 6 patients lost to follow-up. The average FAAM score was 87 (range, 71.4-100). At last follow-up, most patients reported their overall function as “normal” or “nearly normal.” Eradication of infection and satisfactory functional results can be attained after radical debridement, wound closure, and administration of culture-specific IV antibiotics. Level of Evidence: Level IV, retrospective case series.
Reconstruction of the Spring Ligament With a Posterior Tibial Tendon Autograft: Technique Tip
Ryssman, Daniel B., Jeng, Clifford L.

Foot & Ankle International | April 1, 2017 | Volume: 38 | Issue: 4 | Pages: 452-456

10.1177/1071100716682332 Get It

RNA‐seq analysis of clinical‐grade osteochondral allografts reveals activation of early response genes
Yang, Lin , Lewallen, Eric A. , Camilleri, Emily T. , Bonin, Carolina A. , Jones, Dakota L. , Dudakovic, Amel , Galeano‐Garces, Catalina , Wang, Wei , Karperien, Marcel , Larson, A. Noelle , Dahm, Diane L., Levy, Bruce A. , Smith, Jay , Ryssman, Daniel B., Im, Hee‐Jeong , Wijnen, André J. van , Riester, Scott M. , Krych, Aaron J. , Camilleri, Emily , Lin, Yang , Larson, Annalise N, van Wijnen, Andre J, Stuart, Michael J. , Westendorf, Jennifer J. , van Wijnen, Andre J , Krych, Aaron J , Larson, A Noelle , Camilleri, Emily

Journal of Orthopaedic Research | February 25, 2016 | Volume: 34 | Issue: 11 | Pages: 1950-1959

10.1002/jor.23209 Get It

ABSTRACTPreservation of osteochondral allografts used for transplantation is critical to ensure favorable outcomes for patients after surgical treatment of cartilage defects. To study the biological effects of protocols currently used for cartilage storage, we investigated differences in gene expression between stored allograft cartilage and fresh cartilage from living donors using high throughput molecular screening strategies. We applied next generation RNA sequencing (RNA‐seq) and real‐time reverse transcription quantitative polymerase chain reaction (RT‐qPCR) to assess genome‐wide differences in mRNA expression between stored allograft cartilage and fresh cartilage tissue from living donors. Gene ontology analysis was used to characterize biological pathways associated with differentially expressed genes. Our studies establish reduced levels of mRNAs encoding cartilage related extracellular matrix (ECM) proteins (i.e., COL1A1, COL2A1, COL10A1, ACAN, DCN, HAPLN1, TNC, and COMP) in stored cartilage. These changes occur concomitantly with increased expression of “early response genes” that encode transcription factors mediating stress/cytoprotective responses (i.e., EGR1, EGR2, EGR3, MYC, FOS, FOSB, FOSL1, FOSL2, JUN, JUNB, and JUND). The elevated expression of “early response genes” and reduced levels of ECM‐related mRNAs in stored cartilage allografts suggests that tissue viability may be maintained by a cytoprotective program that reduces cell metabolic activity. These findings have potential implications for future studies focused on quality assessment and clinical optimization of osteochondral allografts used for cartilage transplantation. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1950–1959, 2016.
Radiographic and Functional Outcomes Following Bilateral Ankle Fusions
Wilke, Benjamin K. , Ryssman, Daniel B., Turner, Norman S. , Houdek, Matthew T. , Wilke, B K

Foot & Ankle International | September 23, 2014 | Volume: 35 | Issue: 12 | Pages: 1250-1254

10.1177/1071100714551947 Get It

Background: Ankle arthrodesis is considered to be a well-accepted technique for end-stage ankle arthritis. Our purpose was to evaluate outcomes of patients with bilateral ankle arthrodeses with attention to radiographic and functional outcomes. Methods: Medical records of 31 patients were reviewed from 1977 through 2007. All patients had 1 year of clinical follow-up after their contralateral ankle arthrodesis, with an average follow-up of 11.2 years following the initial arthrodesis. Pertinent patient demographics and information pertaining to the operative procedure, complications, and subsequent adjacent joint fusions was collected. Radiographs were reviewed for time to fusion and adjacent joint arthritis. Functional outcomes were measured using the Foot and Ankle Ability Measure (FAAM) and the American Orthopaedic Foot and Ankle Society (AOFAS) Ankle and Hindfoot scale. Results: Ten females and 21 males underwent bilateral ankle fusions at an average age of 57 years at the time of the initial fusion. The contralateral fusion occurred on average 3.1 years following the initial fusion. Radiographic fusion occurred 12 weeks following the initial fusion and 14 weeks following the contralateral fusion. There was a significant increase ( P = .0001) in the average AOFAS score postoperatively in both ankles. The average FAAM score at last follow-up was 70. Adjacent joint arthritis developed in the majority of patients; however, most of the patients were free from adjacent fusions and reported their function as “normal” or “nearly normal” at last follow-up. Conclusion: Bilateral ankle arthrodesis was an acceptable treatment option for patients with bilateral, end-stage ankle arthritis. Level of Evidence: Level IV, retrospective case series.
Total Ankle Arthroplasty: Management of Varus Deformity at the Ankle
Ryssman, Daniel B., Myerson, Mark S.

Foot & Ankle International | July 25, 2012 | Volume: 33 | Issue: 4 | Pages: 347-354

10.3113/fai.2012.0347 Get It