Efficacy of Eccentric Versus Isometric Exercise in Reducing Pain in Runners With Proximal Hamstring Tendinopathy

Study Overview
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Brief Summary
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Tendon injuries are the most common injuries in sports. They are difficult to treat and cause prolonged absence and decreased athlete performance. Proximal hamstring tendinopathy (PHT) is one of them. First described by Puranen and Orava in 1988 as hamstring syndrome. This injury is most common in the active population. PHT is a chronic degenerative injury that is produced by mechanical overload and repetitive stretch. Risk factors include overuse, poor lumbopelvic stability and relative weakness of the hamstring muscles. The phenomenon manifests itself with deep pain in the ischial tuberosity area and projection to the posterior thigh, pain during prolonged sitting, pain during hip flexion and knee extension and pain that increases or arises during running, especially during the swing phase. Risk factors are divided into internal (systemic and biomechanical) and external factors. Internal factors associated with systemic characteristics, include advanced age, sex, obesity, genetics, inflammation and autoimmune conditions, diabetes, hyperlipidemia, and drug use. The external factors, which are more modifiable, are those that depend on the patient's external environment and include training errors such as increasing training volume and / or intensity too quickly and insufficient recovery that cause an overload on the tendon. For PHT two conditions are considered provocative - energy storage, an action that is typical in the late swing phase while running and repetitive movements that cause compressive forces of the tendon on ischial tuberosity. Compressive forces increase as the hip or trunk flex which explains why training errors such as an increase in volume or intensity of the training and non-gradual change in training type, such as hurdle or hills training, are considered to be factors involved in PHT. PHT treatment options include physiotherapy, shock waves, Platelet rich plasma (PRP) and surgical treatment. Non-surgical treatments for tendinopathy includes gradual loading of the tendon under the supervision of the level of pain. The load on the tendon causes an increase in collagen synthesis and an increase in the stiffness and capacity of the tendon which ultimately helps return the athlete to function and reduces the level of pain. Although the injury mechanism is common among runners and athletes from various endurance disciplines (medium and long distance runners, triathletes, etc.) the phenomenon and its treatment has not been sufficiently studied within this population.

Official Title
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Efficacy of Eccentric Versus Isometric Exercise in Reducing Pain in Runners With Proximal Hamstring Tendinopathy

Conditions
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Proximal Hamstring Tendinopathy, Tendinopathy, Eccentric Exercise, Isometric Exercise, Hamstring Tendon Injury

Intervention / Treatment
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* Other: Eccentric protocol
* Other: Isometric protocol


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Medium and long distance runners and endurance athletes (triathlon, Iron Man) over the age of 40 With tendon pain lasting 3 months or more, at the location of hamstring insertion in Ischial tuberosity, that increases during or after running. Exclusion Criteria: Hamstring tear (posterior thigh muscle) according to MRI Stress fractures of the ischium bone Radiated pain in the posterior thigh originating in the lumbar spine, hip joint or sacroiliac joint Other pathologies or rupture of the hamstring muscle Exclude people who have received therapeutic intervention in the last month Medication use for PHT Pain located medially or laterally to the Ischial tuberosity Pregnant women

Ages Eligible for Study
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Minimum Age: 40 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Eccentric protocol<br> | Other: Eccentric protocol<br>* Participants in this arm will perform progressive eccentric exercise protocol<br>|
| Experimental: Isometric protocol<br> | Other: Isometric protocol<br>* Participants in this arm will perform progressive isometric exercise protocol<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Victorian Institute of Sport Assessment-Proximal Hamstring Tendons (VISA-H) questionnaire | VISA-H is a patient reported outcome questionnaire with high psychometric properties for measuring pain, function and sporting activity in patients with PHT | 6 weeks | 
| Isometric and eccentric muscle force |  | 6 weeks | 
| Running performance | measuring running time for 1.5 km | 6 weeks |