THORIR STURLA RAGNARSSON, MD

DAKOTA DUNES, SD

Research Active
Neurological Surgery NPI registered 21+ years 6 publications 1995 – 2025 NPI: 1013910363
LiverCreatinineBiomarkersMuscle, SkeletalKidneyAcute DiseaseHeartSwedenRunningCholangiopancreatography, Endoscopic RetrogradePhysical EnduranceLinear ModelsBicyclingMyoglobinSwimming

Practice Location

575 N SIOUX POINT RD
DAKOTA DUNES, SD 57049-5312

Phone: (605) 217-2667

What does THORIR RAGNARSSON research?

Dr. Ragnarsson studies how physical performance measurements, like jumps and muscle strength, can indicate fatigue and recovery in athletes, especially after high-intensity activities such as triathlons. He also compares how men and women respond to strenuous exercises, like those endured during an Ironman triathlon, revealing important differences in recovery and injury markers. Additionally, he investigates treatment protocols for conditions like acute biliary pancreatitis and their effects on patient outcomes and healthcare costs. His work extends to surgical interventions for chronic neck pain resulting from whiplash injuries.

Key findings

  • Both countermovement jump and isometric mid-thigh pull tests scored above 0.97 in reliability, highlighting their effectiveness in measuring athlete performance post-exercise.
  • Men show higher levels of muscle damage markers, with myoglobin and creatinine elevated after an Ironman triathlon, indicating they may experience greater stress than women.
  • 20% of patients with acute biliary pancreatitis did not receive timely treatment, leading to a readmission rate of 15% compared to only 1.2% for treated patients.
  • Troponin T levels increased significantly after completing the Kalmar Ironman but returned to normal within 5 to 8 days for nearly all athletes.
  • 72.2% of patients undergoing occipital nerve release surgery for whiplash-related neck pain reported significant improvement, though none achieved complete relief.

Frequently asked questions

Does Dr. Ragnarsson study sports performance?
Yes, he focuses on how various tests can measure athlete performance and recovery, especially after intense exercise.
What differences does Dr. Ragnarsson find between male and female athletes?
He has found that men generally exhibit higher levels of muscle damage markers after strenuous activities like triathlons, suggesting differences in recovery.
Has Dr. Ragnarsson researched treatments for pancreatitis?
Yes, he has studied how following treatment guidelines can reduce the chances of recurrent episodes of acute biliary pancreatitis and their associated costs.
Is Dr. Ragnarsson's work relevant for patients with whiplash injuries?
Absolutely, his research on surgical treatments for neck pain related to whiplash has shown significant improvement in many patients.
What kind of biomarkers does Dr. Ragnarsson study in athletes?
He studies various blood biomarkers that indicate heart, liver, kidney, and muscle damage, particularly after endurance events like triathlons.

Publications in plain English

Are counter movement jump and isometric mid-thigh pull tests reliable, valid, and sensitive measurement instruments when performed after maximal cardiopulmonary exercise testing? A sex-based analysis in elite athletes.

2025

Frontiers in physiology

Pojskić H, Schiller J, Pagels P, Ragnarsson T, Melin AK

Plain English
This study looked at two physical tests—the countermovement jump (CMJ) and the isometric mid-thigh pull (IMTP)—to see how reliable and effective they are in measuring fatigue and recovery in elite athletes after intense exercise. The findings showed that both tests are highly reliable, with scores indicating very consistent results (above 0.97 for the overall group), and they can effectively differentiate performance between male and female athletes, particularly in jump height and peak force. This matters because it means these tests can be trusted as tools for coaches and trainers to assess athletes' recovery and performance, ensuring that both male and female athletes are evaluated fairly. Who this helps: This helps athletes and their coaches in optimizing training and recovery strategies.

PubMed

Acute biliary pancreatitis: focus on recurrence rate and costs when current guidelines are not complied.

2017

Scandinavian journal of gastroenterology

Ragnarsson T, Andersson R, Ansari D, Persson U, Andersson B

Plain English
This study looked at how well doctors follow guidelines for treating acute biliary pancreatitis (ABP) and how this affects patients and costs. Researchers analyzed the medical records of 254 patients from 2011 to 2013 and found that 20% did not receive any treatment; among this group, 15 were readmitted for pancreatitis, compared to just 3 who received timely treatment. The average cost for treating mild ABP was about €6,882, while recurrent episodes could cost over €16,000, highlighting that following guidelines can help reduce both the chances of getting sick again and the financial burden. Who this helps: Patients who suffer from acute biliary pancreatitis.

PubMed

Blood biomarkers in male and female participants after an Ironman-distance triathlon.

2017

PloS one

Danielsson T, Carlsson J, Schreyer H, Ahnesjö J, Ten Siethoff L +3 more

Plain English
The study looked at how an Ironman-distance triathlon affects blood markers related to heart, liver, kidney, and muscle damage in both men and women. It found that men had higher levels of certain damage markers, like myoglobin and creatinine, immediately after the race compared to women, who generally showed a milder response. This is important because it suggests that women might recover better from intense physical activity than men. Who this helps: This helps athletes, coaches, and healthcare providers understand how different genders respond to extreme endurance events.

PubMed

[Biochemical changes after strenuous exercise – data from the Kalmar Ironman].

2016

Lakartidningen

Carlsson J, Ragnarsson T, Danielsson T, Johansson T, Schreyer H +2 more

Plain English
This study examined the effects of completing the Kalmar Ironman triathlon on the hearts, muscles, and kidneys of 30 athletes (15 men and 15 women). After the race, many participants showed elevated levels of certain biomarkers indicating stress or damage, including troponin T, which was high enough in most to resemble signs of a heart attack. Fortunately, these levels returned to normal within 5 to 8 days for nearly all athletes, highlighting the body's ability to recover after intense exercise. Who this helps: This information benefits athletes, coaches, and sports medicine professionals.

PubMed

Occipital nerve release in patients with whiplash trauma and occipital neuralgia.

1996

Headache

Magnússon T, Ragnarsson T, Björnsson A

Plain English
Researchers studied the effects of surgery on the greater occipital nerve in patients who suffered from neck pain due to whiplash trauma. Out of 18 surgeries performed on 13 patients, 72.2% reported significant improvement in their pain, although no one achieved complete pain relief. This matters because it shows that this surgical approach can help many people with persistent neck pain following a whiplash injury. Who this helps: Patients suffering from chronic neck pain after whiplash.

PubMed

[Aneurysmal bone cyst, following a skull trauma. A case report.].

1995

Laeknabladid

Arnaldsson OS, Ragnarsson T

Plain English
This study looked at a rare type of bone growth called an aneurysmal bone cyst that appeared after a skull injury. The authors reported on a specific case and highlighted the unique features seen in medical images, as well as the challenges in accurately diagnosing this condition. It’s important because recognizing this condition can help with proper treatment and management, especially since similar cases are not often documented. Who this helps: This helps doctors and patients dealing with skull injuries.

PubMed

Frequent Co-Authors

Tom Danielsson Jörg Carlsson Hendrik Schreyer Patrick Bergman Hari Pojskić Jesper Schiller Peter Pagels Anna K Melin Jonas Ahnesjö Lasse Ten Siethoff

Physician data sourced from the NPPES NPI Registry . Publication data from PubMed . Plain-English summaries generated by AI. Not medical advice.