The iliotibial band revisited: surgical anatomy and imaging-based guidelines for lateral tenodesis in ACL reconstruction

Abstract

Purpose

To provide an updated, clinically oriented review of the iliotibial band (ITB), emphasizing its surgical anatomy, biomechanical relevance, imaging correlates, and role in knee ligament reconstruction, with a focus on lateral extra-articular tenodesis (LET) and anterior cruciate ligament (ACL) augmentation.

Methods

A structured narrative review was conducted, summarizing anatomical, biomechanical, radiological, clinical, and surgical literature. Key elements included gross and histological anatomy of the ITB, its relationship with Kaplan fibers and anterolateral capsulo-fascial structures, imaging assessment using MRI and ultrasound, and evidence supporting ITB-based procedures in selected ACL reconstruction settings.

Results

The ITB functions as both a passive and dynamic stabilizer of the lateral knee and contributes to control of internal tibial rotation, particularly in ACL-deficient or high-risk knees. Its deep capsulo-osseous component, including the Kaplan fibers, forms part of the broader anterolateral restraint system. MRI and ultrasound may support anatomical correlation and evaluation of associated lesions, but imaging findings should be interpreted as complementary to clinical assessment rather than as independent determinants of LET indication. In selected high-risk populations, including young pivoting-sport athletes, revision ACL patients, and patients with generalized laxity, ITB-based LET has been associated with improved rotatory control and reduced graft failure risk when appropriate tensioning principles are respected.

Conclusion

The ITB is a clinically relevant anatomical and biomechanical structure in contemporary ACL reconstruction. Its layered architecture and relationship with Kaplan fibers help explain the rationale for selective LET augmentation. Current evidence supports ITB-based LET as an adjunct in appropriately risk-stratified patients, while imaging should be viewed as supportive for anatomical correlation and associated pathology rather than as a stand-alone basis for surgical decision-making.

Level of evidence

V (Narrative review).

Supplementary Information

The online version contains supplementary material available at https://doi.org/10.1007/s00276-026-03956-1.

Introduction

The iliotibial band as a lateral stabiliser of the knee

The iliotibial band (ITB) is a longitudinal thickening of the fascia lata extending from the iliac crest to Gerdy’s tubercle. Through its continuity with the tensor fasciae latae and gluteus maximus, and its integration with lateral capsulo-fascial structures, the ITB contributes to both dynamic and passive restraint of the lateral knee [48, 49]. Its connection to the anterolateral complex, including femoral attachments commonly described as the Kaplan fibre complex, supports resistance to internal tibial rotation, particularly in the ACL-deficient knee [40].

Historical perspectives

Kaplan [27] described distinct femoral attachments of the ITB (Kaplan fibres), which contributed to the contemporary understanding of anterolateral restraint. Current concepts emphasise force transmission and capsulo-osseous integration rather than a purely friction-based model [11, 24, 51].

Surgical relevance in contemporary practice

In modern practice, ITB-based lateral extra-articular procedures are used to augment ACL reconstruction by improving rotational control and reducing failure risk in selected high-risk patients [8, 14]. In skeletally immature patients, the ITB may serve as a physeal-sparing autograft option with established clinical use [30].

This narrative review provides an updated overview of ITB anatomy and imaging correlates relevant to contemporary knee ligament surgery.

Aim and scope. The review is intentionally ITB-centric: we summarise gross and microanatomy (including the Kaplan fibre complex), relationships with anterolateral capsulo-fascial structures, and practical imaging correlates. To avoid redundancy with the ACL outcomes literature, we provide a concise synopsis of indications/complications and direct readers to recent consensus statements and focused reviews for detailed procedural guidance on LET/LEAPs [45–47].

Anatomical and histological overview

Gross anatomy

The ITB is a dense lateral thickening of the fascia lata, reinforced proximally by the tensor fasciae latae and gluteus maximus, and contributing to restraint of the lateral knee [24, 48, 49]. In addition to its superficial course from the iliac crest to Gerdy’s tubercle, the ITB is commonly described as having a two-layer configuration. The superficial component continues distally along the lateral thigh to its tibial insertion, whereas the deep (capsulo-osseous) component blends with the lateral capsule and distal femur, including the femoral attachment fibres described as the Kaplan fibre complex [11, 27, 43]. This deep architecture is demonstrated in Fig. 1.

Fig. 1.

Deep portion of the iliotibial band and its femoral attachments to the distal femur (Kaplan fibre complex). Black arrows indicate the deep iliotibial band and associated femoral attachment fibres. DITB—deep iliotibial band; KF—Kaplan fibres; LC—lateral femoral condyle; PM—popliteus muscle

Along its course, the ITB blends with the lateral intermuscular septum and contributes distally to lateral capsulo-fascial structures, including the lateral patellar retinaculum [13]. Its spatial continuity with anterolateral structures of the knee is summarised in Figs. 2, 3.

Fig. 2.

Superficial anatomy of the iliotibial band along the lateral aspect of the thigh. The iliotibial band is reinforced proximally by the tensor fasciae latae and gluteus maximus and continues distally towards the lateral knee. White arrowsindicate the superficial iliotibial band and related fibrous structures. TFL—tensor fasciae latae; GM—gluteus maximus; SITB—superficial iliotibial band; P—patella

Fig. 3.

Schematic representation of the iliotibial band and its anatomical relationships within the anterolateral region of the knee. The illustration demonstrates the course of the iliotibial band and its spatial relationships to surrounding lateral structures and adjacent musculature, including its femoral attachments to the distal femur (Kaplan fibre complex). Original illustration by Daniel Casanova

Histological composition

Histologically, the ITB is composed predominantly of type I collagen arranged in parallel longitudinal bundles, consistent with tensile load-bearing function [28, 52]. Smaller proportions of type III collagen and elastin contribute to limited extensibility and viscoelastic behaviour. In chronic overload conditions, the deep (capsulo-osseous) portion particularly near the lateral femoral epicondyle may demonstrate increased cellularity, neovascularisation, and matrix disorganisation [11, 15].

The layered organisation also persists microscopically, with the superficial component characterised by thicker continuous collagen bundles and the deep component blending with capsular and periosteal tissues, including transverse femoral attachment fibres [27, 43]. A comparative summary of ITB layers and their anatomical connections is provided in Table 1.

Table 1.

Comparative overview of ITB layers and anatomical connections

ITB Layer	Primary composition	Connected structures	Functional role
Superficial (Lamina Superficialis)	Dense type I collagen, longitudinal fibers	Tensor fasciae latae, gluteus maximus, lateral patellar retinaculum	Tensile load transmission, hip and knee stabilization
Deep (Lamina Profunda / Capsulo-osseous)	Mixed collagen with capsular integration	Lateral femoral epicondyle, joint capsule, Kaplan fibres, anterolateral ligament (ALL)	Rotational control, anterolateral stabilization, femoral anchorage

Biomechanical function of the iliotibial band

Stabilisation and load transfer

The ITB is a major lateral stabiliser of the knee, integrating passive restraint with dynamic force transmission from the tensor fasciae latae and gluteus maximus to the tibia [11, 24, 48]. Biomechanical data suggest that the ITB maintains baseline tension across mid-range knee flexion, contributing to joint congruency and efficient load distribution [1, 6, 37]. In ACL-deficient knees, the ITB particularly its deep capsulo-fascial component, including the Kaplan fibre complex acts as an important restraint to internal tibial rotation and anterior translation, with changes in restraint behaviour as the band translates relative to the lateral femoral condyle with increasing flexion [11, 40, 43, 51]. Collectively, these properties support the use of ITB tissue as a robust autograft for lateral extra-articular tenodesis (LET) in selected high-risk or revision ACL settings [14, 34].

ITB in dynamic conditions

During functional tasks involving combined flexion and rotation, the ITB contributes to control of tibiofemoral kinematics via its continuity with proximal musculature and its distal capsulo-fascial connections [24]. Distally, its continuity with lateral retinacular and septal structures may also influence patellofemoral mechanics [13].

Functional role of the Kaplan fibre complex and anterolateral restraint

Kaplan fibres are fascial condensations arising from the deep surface of the ITB and attaching to the distal femur and adjacent septal structures [27]. Together with adjacent anterolateral capsulo-fascial structures, they contribute to the broader anterolateral restraint system of the knee [18, 40, 43]. Cadaveric sectioning studies indicate that combined disruption of anterolateral structures and the ACL increases internal tibial rotation and pivot-shift magnitude compared with isolated ACL injury, supporting the clinical rationale for addressing anterolateral restraint in selected cases [5, 38–40].

Segond fracture: anatomy, biomechanics, and imaging

A Segond fracture is an anterolateral tibial plateau avulsion commonly associated with ACL rupture and high-grade pivot shift. Contemporary anatomical and MRI studies link the avulsed fragment primarily to the anterolateral capsule and adjacent anterolateral structures, with variable contribution from the ITB footprint depending on definition and dissection plane [7, 12, 20, 42]. The fragment is typically visible on anteroposterior radiographs; CT can further characterise bony morphology, while MRI delineates associated soft-tissue injury patterns and marrow oedema [20, 42]. Clinically, the finding may indicate anterolateral insufficiency and should prompt careful assessment of rotatory stability and associated lesions.

Clinical and biomechanical take-home principles

The key clinical message is that the ITB should be considered part of a broader anterolateral restraint system rather than an isolated fascial band. Its deep capsulo-osseous component, including the Kaplan fibers, contributes to control of internal tibial rotation, particularly in ACL-deficient or high-risk knees. From a surgical perspective, ITB-based LET should therefore be viewed as a selective adjunct to ACL reconstruction in patients with clinically relevant rotatory instability or increased risk of graft failure, not as a routine addition to every ACL reconstruction. Imaging may support anatomical correlation and identification of associated lesions, but clinical risk stratification remains central to decision-making.

Imaging of the ITB and associated structures

MRI protocols

Sequences: PD-FS, T2-weighted, oblique axial/sagittal

MRI is the preferred modality for evaluating the ITB and related anterolateral structures. Fluid-sensitive sequences (PD fat-suppressed and/or T2-weighted) are most useful for identifying peritendinous oedema, focal thickening, and peritrochanteric or lateral bursitis, while standard T1-weighted images support anatomical orientation. Practical assessment should focus on focal thickening or signal heterogeneity within the ITB, peritendinous fluid, and regional bursal changes. Representative proximal MRI examples at the level of the greater trochanter are shown in Fig. 4 (side-to-side asymmetry) and Fig. 5 (normal reference). Oblique axial and/or sagittal planes aligned with the lateral femoral cortex can improve evaluation of distal ITB attachments and adjacent anterolateral structures [21].

Fig. 4.

Magnetic resonance imaging at the level of the greater trochanter showing a coronal T1-weighted image (left) and axial proton density fat-suppressed (PD-FS) image (right). Purple arrows indicate the iliotibial band superficial to the greater trochanter, demonstrating side-to-side asymmetry with mild thickening and signal heterogeneity on PD-FS imaging

Fig. 5.

Magnetic resonance imaging at the level of the greater trochanter (coronal T1-weighted, left; axial PD-FS, right). Purple arrows indicate the iliotibial band superficial to the greater trochanter, demonstrating a bilaterally normal reference appearance

Visualisation of Gerdy’s tubercle, Kaplan fibres, and anterolateral structures

Gerdy’s tubercle is readily identified on axial images as the distal bony reference for the ITB insertion. The femoral attachment fibres commonly described as the Kaplan fibre complex are best appreciated on oblique axial PD-FS and/or isotropic 3D acquisitions with multiplanar reformatting [43]. When assessed, anterolateral capsulo-fascial structures may be visualised as low-signal bands on thin-slice coronal imaging, with visualisation influenced by slice thickness and positioning [18]. Examples of distal ITB thickening with signal heterogeneity and apparent fibre-bundle lamination are shown in Fig. 6, with a normal distal ITB reference example in Fig. 7.

Fig. 6.

Knee magnetic resonance imaging (axial PD-FS, left; coronal PD-FS, right). Purple arrows indicate the distal iliotibial band at the anterolateral knee, demonstrating thickening with signal heterogeneity and apparent fibre-bundle lamination

Fig. 7.

Knee magnetic resonance imaging (axial PD-FS, left; coronal PD-FS, right). Purple arrows indicate the distal iliotibial band at the anterolateral knee, demonstrating a normal reference appearance

Recommended protocols

For clinically oriented assessment of the ITB and anterolateral region, an MRI protocol should include:

• Field strength: 1.5–3.0 T.

• Slice thickness: ≤ 3 mm (thin-slice coronal imaging for anterolateral structures)

• Core planes/sequences: axial and coronal PD-FS; sagittal T2-weighted (or equivalent fluid-sensitive sequence); axial T1-weighted

• Optional: oblique axial PD-FS aligned with the lateral femoral cortex and/or isotropic 3D acquisition with multiplanar reformatting

• Positioning: neutral to mild knee flexion (typically ~ 20–30°) as tolerated

Ultrasound assessment

Dynamic assessment of ITB gliding

Ultrasound (US) provides high-resolution assessment of the superficial ITB and enables dynamic evaluation during provocative manoeuvres. Using a high-frequency linear transducer, the ITB appears as a hyperechoic fibrillar band in transverse view and as parallel echogenic lines in long-axis view [23]. A representative long-axis ultrasound image at the level of the greater trochanter is shown in Fig. 8. Dynamic testing during motion can assess relative gliding and may reproduce patient symptoms, providing functional correlation. A dynamic transverse cine-loop at the greater trochanter during femoral rotation is provided as Online Resource 1, and a long-axis cine-loop at the lateral femoral epicondyle during approximately 45° knee flexion with tibial rotation is provided as Online Resource 2.

Fig. 8.

Long-axis ultrasound at the level of the greater trochanter. Purple arrows indicate the iliotibial band as a hyperechoic fibrillar structure superficial to the cortical surface of the greater trochanter

Enthesopathy and lateral condylar impingement

US can identify enthesopathic change at the ITB insertion on Gerdy’s tubercle (e.g., cortical irregularity, periosteal reaction, and/or Doppler signal), as shown in Fig. 9 [10]. In the mid-to-distal femoral region, US may also demonstrate bursal distension or echogenic scarring between the ITB and the lateral femoral condyle in cases of chronic impingement, often correlating with focal tenderness on probe compression.

Fig. 9.

Long-axis ultrasound at the level of Gerdy’s tubercle. Purple arrows indicate the distal iliotibial band at its tibial insertion on Gerdy’s tubercle

CT and 3D imaging

Although not routinely used for soft-tissue assessment, computed tomography (CT) may provide complementary information by depicting bony landmarks relevant to ITB-related procedures, including Gerdy’s tubercle and the lateral femoral epicondyle, and by clarifying osseous morphology when radiographs are equivocal. In revision settings, CT (including 3D reconstructions where appropriate) can assist in identifying prior tunnel positions and hardware location, thereby facilitating preoperative planning and helping to avoid tunnel convergence.

Clinical interpretation of imaging findings

Imaging findings should be interpreted as supportive rather than determinative for LET indication. MRI and ultrasound may help identify associated anterolateral injury patterns, Kaplan fiber abnormalities, postoperative findings, and alternative causes of lateral knee symptoms. However, the decision to perform LET remains primarily based on clinical risk stratification, including pivot-shift grade, revision status, age, sporting demands, generalized laxity, and surgeon assessment of rotatory instability.

Surgical application of the iliotibial band in knee ligament reconstruction

Role and evolution of ITB-based augmentation

Historical evolution of LET techniques

Lateral extra-articular tenodesis (LET) was developed to address anterolateral rotatory instability prior to the modern era of arthroscopic ACL reconstruction. Classic techniques such as MacIntosh, Lemaire and Ellison utilised a strip of the ITB, typically maintaining the distal attachment at Gerdy’s tubercle and varying the graft route relative to the lateral collateral ligament (LCL) and the method of femoral fixation [9, 31, 41]. With the evolution of anatomic intra-articular ACL reconstruction, these procedures shifted from stand-alone operations to adjunctive augmentation in selected high-risk patients. Contemporary clinical programmes (including STABILITY and SANTI) have re-established the role of ACL reconstruction combined with LET in reducing graft failure and improving rotatory control in appropriate populations [14, 44].

Modern use of ITB as an autograft: advantages and harvest (anatomy-to-technique relevance)

The ITB has regained attention as a low-morbidity autograft option for adjunctive procedures, including LET and anterolateral augmentation, particularly in high-risk and revision settings [8, 44]. Key advantages include preservation of knee flexor strength and favourable donor-site morbidity compared with hamstring harvest, while maintaining adequate mechanical properties for anterolateral reinforcement [25]. Importantly, anatomical understanding directly informs technique: distal fixation is anchored at Gerdy’s tubercle, while the femoral attachment region and the Kaplan fibre complex provide critical anatomic context for graft positioning and interpretation of anterolateral restraint [27, 43]. In practice, the graft is harvested as a strip with the distal attachment preserved, routed either superficial to or deep to the LCL depending on the chosen technique, and fixed on the lateral femur with controlled tensioning to avoid over-constraint [8, 44].

Biomechanical and clinical foundations of ACL + LET

The biomechanical rationale for LET is based on improving anterolateral restraint and reducing internal tibial rotation in ACL-deficient knees, thereby unloading the intra-articular graft during early flexion [18, 29, 40]. Cadaveric studies indicate that disruption of anterolateral capsulo-fascial structures and deep ITB components, including the Kaplan fibre complex, increases rotatory laxity compared with isolated ACL injury [27, 40, 51]. Clinically, ITB-based LET may reduce peak graft strain and improve pivot-shift control, supporting its use in selected high-risk populations [35, 36].

Comparative outcomes: isolated ACL reconstruction vs ACL + LET

Randomised and prospective studies support the benefit of adding LET to ACL reconstruction in selected high-risk patients. The STABILITY I trial reported lower graft failure and improved pivot-shift control in the ACL + LET group without clinically meaningful loss of motion or clear evidence of over-constraint when appropriately tensioned [14]. Cohort data from the SANTI group similarly reported reduced re-injury and improved rotatory stability with combined procedures [44]. Meta-analyses indicate lower revision/re-injury risk and improved rotatory control in younger pivoting-sport athletes and other high-risk subgroups [8]. Key comparative outcomes are summarised in Table 1.

Indications and patient selection

Indications and clinical rationale for LET augmentation

Despite advances in anatomic ACL reconstruction, a subset of patients remains at increased risk of graft failure or residual anterolateral rotatory instability. In such cases, ITB-based LET can improve rotatory control and provide graft protection [8, 14]. LET is most commonly considered when one or more of the following are present:

• High-grade pivot shift (Grade II–III) [44].

• Age < 25 years with return to pivoting/contact sport [16, 50].

• Generalised ligamentous laxity (e.g. Beighton ≥ 4) [19, 25].

• Revision ACL reconstruction following failure under rotatory load [8, 14].

• Anatomical risk factors (e.g. increased posterior tibial slope; marked recurvatum).

• Prior contralateral ACL rupture or demonstrated lateral translation/rotatory instability [22].

Revision ACL surgery and rotatory laxity

Revision ACL reconstruction carries a higher risk of failure, and persistent anterolateral rotatory instability may contribute to graft overload [8, 14]. In selected revision cases, adding ITB-based LET may improve rotatory control and provide additional protection for the intra-articular graft, particularly in high-demand patients or when residual pivot shift is present [25, 29].

Multi-ligamentous injury and ITB contribution

In multi-ligamentous knee injuries with an anterolateral rotatory component, ITB-based augmentation may provide supplementary restraint as part of a broader reconstruction strategy. In this setting, LET should be considered an adjunct rather than a primary stabilizer, particularly when combined ACL and anterolateral or posterolateral insufficiency is present [22, 25].

Skeletally immature patients: distinction from adult LET augmentation

In skeletally immature patients, physeal-sparing ACL reconstruction techniques are used to minimise the risk of growth disturbance. ITB-based physeal-sparing ACL reconstruction has been reported as an established option in selected prepubescent patients because it can avoid transphyseal tunnels while restoring functional stability [30]. However, this concept should be distinguished from ITB-based lateral extra-articular tenodesis used as an adjunct to intra-articular ACL reconstruction in adolescents or adults. In the present review, pediatric ITB-based ACL reconstruction is mentioned only to clarify this distinction and should not be interpreted as a recommendation to use LET as a substitute for standard physeal-sparing ACL reconstruction.

A structured comparison of commonly used ITB-based techniques, including graft route, fixation concepts, and practical decision-making context, is provided in Table 2.

Table 2.

Summary of ITB-based techniques and practical decision-making context

Technique	Graft Route/Approach	Fixation concept	Typical clinical context	Practical decision-making relevance
Modified Lemaire	Pedicled ITB strip passed deep to the LCL	Femoral fixation with screw, staple, or anchor	High-grade pivot shift, revision ACL reconstruction, young high-risk athletes	One of the most commonly used contemporary LET procedures; favoured when strong additional rotatory control is desired
MacIntosh	Longitudinal ITB strip routed beneath the LCL	Soft-tissue or femoral fixation	Generalised ligamentous laxity, high-demand athletes	Historical foundation of many modern LET techniques; may be considered when broad ITB reinforcement is preferred
Ellison	Distal ITB detached and re-routed deep to the LCL before reattachment	Distal soft-tissue or bony fixation	Selected cases of rotatory instability	Avoids femoral tunnel creation and may be attractive when tunnel convergence is a concern
Micheli-type physeal-sparing ITB reconstruction	ITB strip tunnelled subperiosteally without transphyseal drilling	Periosteal fixation and sutures	Skeletally immature patients requiring ACL reconstruction	Represents a pediatric ACL reconstruction strategy rather than adult LET augmentation; included to clarify the distinction
ITB-based anterolateral augmentation	ITB strip fixed to the lateral femur and/or proximal tibia	Anchor or screw fixation	Combined ACL reconstruction with significant anterolateral insufficiency	Primarily used as an adjunct to ACL reconstruction when additional rotatory restraint is considered beneficial

This summary is intended to support technique selection based on patient factors and surgical context rather than to provide procedural instructions.

Key technical principles

ITB-based LET is typically performed using a distally attached ITB strip routed relative to the LCL and fixed on the lateral femur with controlled tensioning [29, 44]. Key principles include:

• Preserve distal attachment at Gerdy’s tubercle (anchor point).

• Choose graft route (superficial vs sub-LCL) according to technique and goals [29].

• Femoral fixation should respect anatomic landmarks and avoid tunnel convergence with the ACL socket [44].

• Fixation is commonly performed in ~ 30–45° flexion with neutral tibial rotation to minimise over-constraint [44].

• Avoid over-tensioning, particularly in full extension, to prevent altered kinematics [8].

• Confirm rotatory glide intra-operatively and reassess pivot shift after fixation [25].

Outcomes and evidence-based results (condensed)

Across RCTs and prospective cohorts, ACL + LET provides improved pivot-shift control and lower graft failure rates in selected high-risk patients without a consistent increase in stiffness when tensioning principles are respected [14, 44]. Meta-analytic data support benefit in younger pivoting-sport athletes, revision cases, and hyperlax individuals [8]. Comparative results are summarised in Table 3.

Table 3.

Evidence-Based Outcomes of ACL + LET

Study / author	Population / design	Main findings
Getgood et al. [14]—STABILITY I	RCT, n = 618, young athletes	Reduced graft failure and improved pivot-shift control; no clinically meaningful increase in stiffness/over-constraint reported
Devitt et al. [8]—Meta-analysis	Meta-analysis (selected studies)	Lower re-injury/revision risk with LET in selected populations; no consistent increase in arthrofibrosis
Sonnery-Cottet et al. [44]—SANTI cohort	Prospective cohort	Improved rotatory stability and lower re-injury rates with combined ACL + LET approach
Inderhaug et al. [25]	Revision ACL (cohort/clinical series)	LET as adjunct associated with improved rotatory control and graft protection in revision settings
Kocher et al. [30]	Paediatric, physeal-sparing ITB technique	Excellent functional outcomes and return to sport; no growth disturbance reported in mid-term follow-up
Kittl et al. [29]	Biomechanical/cadaveric studies	LET reduces rotational laxity and can reduce load on intra-articular ACL graft under simulated conditions

Key evidence from randomised trials, cohorts, and meta-analyses supporting ACL reconstruction with LET is summarised in Table 3.

Overall, the evidence supports selective use of LET to reduce failure and improve rotatory stability in appropriately risk-stratified patients.

Future directions

Three-dimensional MRI acquisitions (e.g., SPACE, VISTA) enabling isotropic reconstructions may further improve visualisation of the iliotibial band and adjacent anterolateral structures, particularly in complex or revision settings [3, 4, 33]. Dynamic ultrasound is also likely to expand its role by enabling functional assessment of ITB mobility and compressive behaviour over the lateral femoral condyle, with potential value in postoperative monitoring [17, 26]. From a reconstructive perspective, the ITB remains an attractive low-morbidity autograft source beyond ACL augmentation, including selected multi-ligament reconstructions [25, 44]. Parallel advances in tissue engineering are focusing on scaffold-based and multilayer constructs designed to mimic native enthesis architecture and improve biological integration, including approaches incorporating mesenchymal stem cells [2, 32]. Overall, future work should prioritise clinically translatable imaging–anatomy correlation and high-quality comparative outcome studies to refine patient selection and standardise technique-specific parameters.

Conclusion

The iliotibial band (ITB) is a key anatomical and biomechanical contributor to lateral knee stability. Its layered continuity with the tensor fasciae latae, gluteus maximus and lateral septal structures, including femoral attachment fibres commonly described as the Kaplan fibre complex, supports its role in restraining rotatory laxity in selected clinical contexts. Modern imaging improves visualisation and correlation with symptoms, while ITB-based lateral extra-articular tenodesis can provide clinically relevant graft protection and improved rotatory control in appropriately risk-stratified patients.

Supplementary Information

Below is the link to the electronic supplementary material.

Abbreviations

ACL

Anterior cruciate ligament

ALL

Anterolateral ligament

CT

Computed tomography

DUS

Dynamic ultrasound

ITB

Iliotibial band

LET

Lateral extra-articular tenodesis

LCL

Lateral collateral ligament

MLKIs

Multi-ligamentous knee injuries

MRI

Magnetic resonance imaging

PD-FS

Proton density fat-suppressed (MRI sequence)

PLC

Posterolateral corner

TFL

Tensor fasciae latae

US

Ultrasound

Author contributions

Łukasz Olewnik: Conceptualization, methodology, literature analysis, writing—original draft, supervision. Ingrid C. Landfald: Literature search, figure design, writing—review and editing. Robert F. LaPrade: Clinical interpretation, critical review, validation of surgical relevance. Daniel Casanova: Literature search, figure design, writing—review and editing. Michał Podgórski: Clinical interpretation, critical review, validation of surgical relevance. Bartosz Gonera: Data curation, anatomical correlation, manuscript editing. All authors approved the final version of the manuscript and agreed to be accountable for all aspects of the work.

Funding

No funding was received for the preparation of this manuscript.

Data availability

No datasets were generated or analysed during the current study.

Declarations

Conflict of interest

The authors declare no conflicts of interest related to this work.

Ethical approval

This article does not contain any studies with human participants or animals performed by any of the authors.

Informed consent

Not applicable.