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Unnur J贸nsd贸ttir: Fear鈥檚 impact post Achilles tendon rupture
Achilles tendon rupture is a common injury, with about 20 percent of individuals unable to return to their previous level of physical activity post-injury. Unnur S忙d铆s J贸nsd贸ttir has investigated the causes, identifying fear as a significant obstacle.

UNNUR S脝D脥S J脫NSD脫TTIR
Dissertation Defense: December 15, 2023 (click for details)
Doctoral Thesis:
Research Area: Orthopaedics
Sahlgrenska Academy, The Institute of Clinical 91探花s
What led to your thesis?
鈥淭hose who suffer from Achilles tendon rupture are typically active, often middle-aged men who engage in activities requiring quick changes of direction. Approximately 20 percent of them do not resume their previous level of activity. My aim was to uncover the reasons behind this,鈥 says Unnur J贸nsd贸ttir, a physiotherapist living in Reykjavik, Iceland.
She works at G谩ski Sj煤kra镁j谩lfun clinic, specializing in sports injuries, rehabilitation, and return to activity.

鈥淢ental Support to Patients鈥
Could you summarize your research?
鈥淚've examined the foot structure on both the injured and healthy sides after Achilles tendon rupture, the impact of fatigue on lower extremity kinetics, and how the fear of reinjury affects biomechanics post-rupture, as well as crucial factors influencing return to physical activity.鈥
What are the key findings and their practical implications?
鈥淚 consider three aspects critical in my research. Firstly, the value of engaging patients in treatment discussions, enabling them to understand the process. Secondly, it's crucial to provide mental support to ensure patients aren't hesitant to use their leg and foot,鈥 says Unnur J贸nsd贸ttir, adding:
鈥淭he third aspect emphasizes the significance of overall body strength training following an Achilles tendon rupture. A practical benefit of these findings is the potential for healthcare professionals to employ them as guidance in their practice.鈥

Half refrained due to fear
Unnur J贸nsd贸ttir鈥檚 thesis indicates fear as a limiting factor among patients with previous Achilles tendon ruptures. In one study, half of the participants admitted refraining from certain physical activities due to fear of reinjuring the tendon.
Those expressing fear exhibited reduced peak power in the ankle joint (on the previously injured side) during a single-leg drop countermovement jump (CMJ). Conversely, they displayed increased compensatory power in the knee joint.
鈥淭hese results raise the question of whether a weaker strength on the injured side caused this difference or if patients simply feared utilizing their strength during the drop CMJ,鈥 says Unnur J贸nsd贸ttir, further noting:
鈥淎symmetry in power distribution, as observed in the 鈥榝ear group鈥, might elevate the risk of overuse injuries later in life.鈥
Canceled trips to Gothenburg
What has been enjoyable about the PhD project?
鈥淚t鈥檚 fun and rewarding to be part of the team at the 鈥楻 House鈥 lab at Sahlgrenska University Hospital M枚lndal and to attend conferences to present our research.
And what has been challenging?
鈥淛ust before Covid, I moved back to Iceland but had plans to visit Gothenburg for courses and collaborations with colleagues a few times year. Due to the pandemic, it became impossible, hence courses and meetings to be done via digital platforms.
Your decision to pursue your PhD at the University 91探花 鈥 does it relate to J贸n Karlsson, a fellow Icelander and professor of orthopaedics and sports traumatology?
鈥淚 arrived in Gothenburg in 2017 to work at IFK-Kliniken Rehab. Annelie Brorsson, now my primary supervisor, also worked there. When she learned of my interest in research, she suggested applying for a doctoral position at the University 91探花. One of her selling points was that J贸n Karlsson worked there, and he also became one of my supervisors. Everything clicked so well that I鈥檒l now defend my thesis in December.鈥
Text: Jakob Lundberg