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Information about a piece of news titled Øystein Lian defends his PhD dissertation May 11th!

Øystein Lian defends his PhD dissertation May 11th!

Intoduction

Øystein Lian MD, who is a fellow at the Oslo Sports Trauma Research Center, will defend his dissertation ”On the causes of patellar tendinopathy” for the PhD-degree at the University of Oslo on Friday May 11th, 2007 at the Medical faculty, University of Oslo.

Øystein Lian (08.08.1954) was born in Kristiansund, Møre og Romsdal. He finished “reallinjen” in 1973. In 1981, he finished his medical training at the University of Oslo. Lian started his PhD program at the Norwegian School of Sport Sciences in 2000. Professor dr. med. Roald Bahr at the Oslo Sports Trauma Research Center, the Norwegian School of Sport Sciences has been his main supervisor and professor dr.med. Lars Engebretsen at the Oslo Sports Trauma Research Center, the Norwegian School of Sport Sciences and Ullevaal University Hospital has been the second supervisor. The aim of this thesis was to study the causes of tendinopathy localized to the patellar tendon.

 

The studies
In Paper I we estimated the prevalence of jumper’s knee in different sports among female and male athletes in a cross-sectional study, in order to correlate the prevalence to the loading characteristics of the extensor mechanism in these sports. The study showed that the prevalence of jumper’s knee is high in sports characterized by high demands on speed and power for the leg extensors. The symptoms are often serious, resulting in long-standing impairment of athletic performance.


In Paper II we assessed the ultrasound characteristics of the patellar tendon in two groups of volleyball players, one group without knee symptoms and one group with symptoms of jumper's knee. This study suggests that the specificity and sensitivity of ultrasonography is low in the evaluation of patients with mild symptoms of jumper's knee.

 
In Paper III and IV we compared the jumping capacity between a group of male volleyball players and controls. In conclusion, athletes with jumper's knee demonstrated better performance than healthy athletes in jump tests, particularly in ballistic jumps involving eccentric force generation. This points to these characteristics as risk factors for jumper's knee.

 
In Paper V, we found that chronic painful patellar tendons exhibited increased occurrence of sprouting non-vascular sensory, substance P-positive nerve fibers and decreased occurrence of vascular sympathetic nerve fibers, positive to tyroxin hydroxylase (a marker for noradrenaline) compared with controls.

 
Paper VI was a case-control study to see if an apoptotic process is part of the pathophysiology in tendinopathy. There was a significantly higher number of apoptotic cells per unit area in tendinopathic samples compared with controls. Although the tendinopathic samples displayed increased cellularity, the apoptotic index was significantly higher. This study confirms that apoptosis is a feature of tendinosis.


Commitee:
Leader: Prof. dr. philos. Inger Holm,
1. opponent: Prof. dr. med. Michael Kjær
2. opponent: Prof. dr. med. Håkan Alfredson

 

Introductory lecture:

Thursday 10.05 kl 17.00, Auditoriet Patologibygget, Ullevaal Hospital

Title: To be announced

 

PhD-defence:

Friday 11.05, kl 15.15. , Gamle Festsal, Ullevaal Hospital

Title: "On the causes of patellar tendinopathy"