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Adductor Longus Tenotomy & the BKFO Test

The Effect of an Adductor Longus Tenotomy on the Bent Knee Fall Out Test

Status
Completed
Phases
Unknown
Study type
Observational
Source
ClinicalTrials.gov
Registry ID
NCT04453592
Enrollment
60
Registered
2020-07-01
Start date
2019-11-22
Completion date
2021-01-18
Last updated
2025-03-03

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Adductor Tendinitis

Brief summary

The bent knee fall out test (BKFO) is a common test for hip adductor flexibility. It is unknown whether the BKFO actually tests the the adductors or potentially hip range of motion instead. In this study, the BKFO test is performed in the operating theater before and after an adductor longus tenotomy.

Detailed description

Adductor-related groin pain is the most common type of groin pain in athletes, and pain at the proximal adductor longus insertion is a key finding in the diagnosis of longstanding groin pain. Tightness or shortening of the adductor longus is considered both a cause and effect of pain, that can lead to increased tension at the proximal insertion, thus playing a role in the persistence of longstanding adductor-related pain. For patients who do not respond sufficiently to non-surgical procedures, an adductor longus tenotomy is a surgical option that is considered to reduce tension at the proximal adductor longus insertion assisting in reduction of pain and return to sport. The bent knee fall out test (BKFO) is one of the most commonly used tests to test adductor flexibility. This test involves a combined hip movement with hip flexion, abduction, and external rotation, and a high result is generally considered to be related to adductor muscle tightness, specifically that of the adductor longus. It is uncertain whether the BKFO test is actually measuring adductor muscle flexibility or hip joint range of motion, as the test results may also be affected by a femoral head cam morphology. A slightly different test, called the Patrick FABER's test, involves a similar movement and is mainly used as a hip joint pain provocation test. By cutting the adductor longus tendon, thereby removing the effect of potential adductor longus tightness, it will be possible to show if and how much the flexibility of this muscle affects the BKFO test results. This will assist in future considerations of what this test is actually testing. The aim of this study is to investigate the immediate effect of an adductor longus tenotomy on the results of the bent knee fall out test.

Interventions

OTHERNo intervention assigned as part of this study.

The intervention included in this study is part of routine medical care, and not assigned as a result of study participation. This study includes only the addition of a measurement; the bent knee fall out test. Therefore, we believe this study design is observational, and in line with the provided observation study design definition: Observational: studies in human beings in which biomedical and/or health outcomes are assessed in predefined groups of individuals. Participants in the study may receive diagnostic, therapeutic, or other interventions, but the investigator does not assign specific interventions to the study participants. This includes when participants receive interventions as part of routine medical care, and a researcher studies the effect of the intervention. See uploaded study protocol for further details.

Sponsors

Clinique du sport
CollaboratorUNKNOWN
Aspetar
Lead SponsorOTHER

Study design

Observational model
CASE_ONLY
Time perspective
PROSPECTIVE

Eligibility

Sex/Gender
MALE
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* adults (\>18 years old) * athletes (recreational or elite) * clinical diagnosis of adductor-related groin pain * patients undergoing unilateral or bilateral adductor longus tenotomy by one general surgeon.

Exclusion criteria

* No specific

Design outcomes

Primary

MeasureTime frameDescription
Change in the Bent Knee Fall Out TestBaseline pre-surgery and immediately after the surgery.The patient lies supine on the surgical table with app. 90° knee flexion, 45° hip flexion, and the feet together and the hips in external rotation (also known as the frog-leg position. Standardization of position is achieved by flexing one leg first, so the medial malleolus is placed next to the medial knee joint line of the contra-lateral leg. The knee is then moved laterally, externally rotating the hip with the plantar surface placed towards the contra-lateral leg. The contra-lateral leg is then flexed, and the plantar surfaces of the feet are aligned. The distance between the most distal point on the head of the fibula and the surface of the surgical table is measured using a rigid tape measure and distance is recorded in cm to the nearest 0.5 cm

Countries

France

Participant flow

Participants by arm

ArmCount
Demographic Data of All Athletes
Demographic data (age, height, weight, BMI) for all included patients described in the baselines measures.
60
Total60

Baseline characteristics

CharacteristicDemographic Data of All Athletes
Age, Continuous27 years
BMI23.8 kg/m2
Height180.4 cm
STANDARD_DEVIATION 7.8
Race and Ethnicity Not Collected— Participants
Sex: Female, Male
Female
0 Participants
Sex: Female, Male
Male
60 Participants
Weight78 Kg

Adverse events

Event typeEG000
affected / at risk
deaths
Total, all-cause mortality
0 / 60
other
Total, other adverse events
0 / 60
serious
Total, serious adverse events
0 / 60

Outcome results

Primary

Change in the Bent Knee Fall Out Test

The patient lies supine on the surgical table with app. 90° knee flexion, 45° hip flexion, and the feet together and the hips in external rotation (also known as the frog-leg position. Standardization of position is achieved by flexing one leg first, so the medial malleolus is placed next to the medial knee joint line of the contra-lateral leg. The knee is then moved laterally, externally rotating the hip with the plantar surface placed towards the contra-lateral leg. The contra-lateral leg is then flexed, and the plantar surfaces of the feet are aligned. The distance between the most distal point on the head of the fibula and the surface of the surgical table is measured using a rigid tape measure and distance is recorded in cm to the nearest 0.5 cm

Time frame: Baseline pre-surgery and immediately after the surgery.

ArmMeasureValue (MEAN)Dispersion
TenotomyChange in the Bent Knee Fall Out Test3.9 cmStandard Deviation 2

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026