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Seeber GH1,2, Lierly M2, Bassett C2, Douthit C2, Wilhelm M3, Sargent E4, Browne K5, Lazovic D1, Brismée J-M2, Gilbert KK2, Sizer PS2
1University Hospital for Orthopaedics and Trauma Surgery Pius-Hospital, Medical Campus University of Oldenburg, Oldenburg, Germany, 2Center for Rehabilitation Research, Texas Tech University Health Sciences Center, Lubbock, Texas, United States, 3Walsh University, North Canton, Ohio, United States, 4University of Vermont, Department for Rehabilitation and Movement Sciences, Burlington, United States, 5University of Texas at El Paso, College of Health Sciences, El Paso, United States
Background: Iliotibial Band Syndrome (ITBS) is the most common overuse injury to the lateral knee in active individuals. Iliotibial Band (ITB) stretching is a frequently suggested approach for reducing ITB dysfunction and ITBS symptoms. However, anatomical, biomechanical, and physiological explanations for treatment response remain under debate. Authors recently reported that ITB stretching did not produce appreciable mid-substance ITB tissue deformation. Thus, the mechanism behind changes in ITBS symptoms and hip ADduction range of motion (ROM) after an ITB stretching regimen are not well understood. The lateral intermuscular septum (LIMS) firmly anchors the ITB to the femur. As a part of the deep lower limb fascia, the LIMS contains myofibroblasts, possibly rendering this tissue responsive to ITB stretching. However, the LIMS' role on constraining hip ADduction is unknown.
Purpose: This within-specimen repeated measures in-situ design aimed to evaluate the constraining effect of the LIMS on passive hip ADduction. It was hypothesized that a LIMS release from the ITB will significantly increase passive hip ADduction, thus testing the LIMS' role in constraining hip ADduction and offer a testable mechanism possibly responsible for changed hip ADduction after stretching.
Methods: Metal markers were inserted into the anterior superior iliac spines (ASIS) bilaterally and the test side femur (femoral marker 1/F1: 5 cm proximal from patellar basis; femoral marker 2/F2: midpoint between ipsilateral ASIS and F1) of eleven un-embalmed human cadavers. With the specimen supine, the test-side lower limb was passively ADducted until maximum passive hip ADduction was reached. This movement was repeated three times each within two conditions:
(1) ITB-LIMS-complex intact and
(2) ITB-LIMS-complex separated.
Digital video of marker displacement was captured throughout each trial. Still images from a start and end position were extracted from each video sequence. Two lines were constructed between the markers:
(1) “ASIS line”- between the two ASIS markers; and
(2) “thigh line”-between F1 and F2. A custom MATLAB program was used to calculate changes between frontal plane hip ADduction angles 𝛼(= 90° angle between ASIS line and thigh line; starting position) and 𝛽(= angle between ASIS line and thigh line in maximum available passive hip ADduction; end position).
Results: Mean change in passive hip ADduction after ITB-LIMS-complex separation was -0.3° (SD 1.6°;95% CI: -1.33,0.76). A paired samples t-test revealed a non-significant difference (t=-.611; p=.555) in passive hip ADduction for the ITB-LIMS-separated condition (18.8±3.9°) versus the ITB-LIMS-intact condition (18.5°±4.7°).
Conclusion(s): The LIMS does not appear to have a constraining effect on passive hip ADduction ROM in un-embalmed cadavers. Future research should evaluate the constraining effect of other selected tissues and conditions on hip ADduction ROM. Furthermore, inflammatory, metabolic, viscoelastic, and sensorimotor control properties within the ITB in response to stretching should be investigated.
Implications: In the absence of any appreciable passive hip ADduction ROM changes in response to LIMS release from the ITB, one must further inquire into why clinically stretching an inextensible structure such as the ITB can effectively reduce ITBS symptoms and increase hip ROM.
Keywords: Iliotibial Band Syndrome, lateral inter-muscular septum, anatomy
Funding acknowledgements: No funding has been received for this study.
Purpose: This within-specimen repeated measures in-situ design aimed to evaluate the constraining effect of the LIMS on passive hip ADduction. It was hypothesized that a LIMS release from the ITB will significantly increase passive hip ADduction, thus testing the LIMS' role in constraining hip ADduction and offer a testable mechanism possibly responsible for changed hip ADduction after stretching.
Methods: Metal markers were inserted into the anterior superior iliac spines (ASIS) bilaterally and the test side femur (femoral marker 1/F1: 5 cm proximal from patellar basis; femoral marker 2/F2: midpoint between ipsilateral ASIS and F1) of eleven un-embalmed human cadavers. With the specimen supine, the test-side lower limb was passively ADducted until maximum passive hip ADduction was reached. This movement was repeated three times each within two conditions:
(1) ITB-LIMS-complex intact and
(2) ITB-LIMS-complex separated.
Digital video of marker displacement was captured throughout each trial. Still images from a start and end position were extracted from each video sequence. Two lines were constructed between the markers:
(1) “ASIS line”- between the two ASIS markers; and
(2) “thigh line”-between F1 and F2. A custom MATLAB program was used to calculate changes between frontal plane hip ADduction angles 𝛼(= 90° angle between ASIS line and thigh line; starting position) and 𝛽(= angle between ASIS line and thigh line in maximum available passive hip ADduction; end position).
Results: Mean change in passive hip ADduction after ITB-LIMS-complex separation was -0.3° (SD 1.6°;95% CI: -1.33,0.76). A paired samples t-test revealed a non-significant difference (t=-.611; p=.555) in passive hip ADduction for the ITB-LIMS-separated condition (18.8±3.9°) versus the ITB-LIMS-intact condition (18.5°±4.7°).
Conclusion(s): The LIMS does not appear to have a constraining effect on passive hip ADduction ROM in un-embalmed cadavers. Future research should evaluate the constraining effect of other selected tissues and conditions on hip ADduction ROM. Furthermore, inflammatory, metabolic, viscoelastic, and sensorimotor control properties within the ITB in response to stretching should be investigated.
Implications: In the absence of any appreciable passive hip ADduction ROM changes in response to LIMS release from the ITB, one must further inquire into why clinically stretching an inextensible structure such as the ITB can effectively reduce ITBS symptoms and increase hip ROM.
Keywords: Iliotibial Band Syndrome, lateral inter-muscular septum, anatomy
Funding acknowledgements: No funding has been received for this study.
Topic: Musculoskeletal: lower limb
Ethics approval required: No
Institution: Texas Tech University Health Sciences Center
Ethics committee: Anatomy SubCommittee at TTUHSC
Reason not required: This project was completed at the Texas Tech University Health Sciences Center (TTUHSC) gross anatomy lab. Such cadaveric research did not require ITB approval or oversight at TTUHSC. Investigations using cadaveric specimen were conducted in accordance with TTUHSC policies and regulations as determined by the Texas State Anatomical Board (TSAB). Any violations at TTUHSC are internally reviewed by an anatomical research committee and the review is reported to that TSAB, who then externally reviews the violation. There were no violations related to this study.
All authors, affiliations and abstracts have been published as submitted.
