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Anatomy & Biomechanics

Elbow anatomy & biomechanics: ulnohumeral, radiocapitellar joints, valgus stress, and implications for UCL injury/OCD in throwers.

85 citationsUpdated Oct 2026

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Overview

Elbow stability and complex kinematics depend on the integration of bony articulation and soft-tissue stabilizers [13]. Understanding these biomechanical principles and injury mechanisms provides essential insight into the variations of pathology observed in complex elbow dislocations [3]. Thorough anatomical knowledge is critical for surgeons to comprehend the biomechanics of rupture and reconstruction, particularly to avoid nerve injuries during procedures involving the distal biceps tendon [5]. In the context of upper extremity trauma, detailed anatomic knowledge and preparation are vital for comprehensive surgical exposures and coverage [6]. Proper management of proximal ulna fractures specifically requires accounting for the complex biomechanics of the elbow joint [22].

The anterior bundle of the medial ulnar collateral ligament serves as the primary restraint to valgus loads [23]. When performing tendon reconstructions for elbow soft tissue stabilizers, structures should be tightened at 30 degrees of flexion rather than 90 degrees [23]. Longitudinal stability of the forearm relies on the coordinated function of the radial head, interosseous membrane, and distal radioulnar joint [14]. While biomechanical and clinical studies are needed to determine the true clinical relevance of anatomic variations in the ulnar greater sigmoid notch coverage angle [1], the evaluation of the elbow generally requires an understanding of anatomy, biomechanics, and diagnostic tests, with particular attention to functional biomechanics when treating complex pathology [11].

Broader upper limb management also draws on these foundational principles. Detailed knowledge of anatomical situations in areas of pin implantation is of great importance for unilateral external fixation in the upper limb [25]. For hand surgeons managing upper limb spasticity, a thorough understanding of biomechanical principles and neurological pathways is necessary [10]. In shoulder arthroplasty, understanding normal and degenerative anatomy is necessary to restore joint function and prevent complications such as glenoid loosening or cuff failure [9]. Functional bracing supports the beneficial effects of movement at the fracture site based on research relating to the biology and biomechanics of fracture healing [18]. Eight studies followed International Society of Biomechanics standards for quantifying upper body kinematics during functional upper limb tasks [2]. The physiology of joints is drawn from previously published accounts and updated with relatively recent findings, omitting unverified or controversial studies [81].

Osseous Anatomy

Distal Humerus

The distal humeral groove follows a helical path, which serves as the anatomical origin of the vortical movement of the elbow joint [27]. Cartilage thickness on the distal humerus is not uniform; this variation modifies the morphologic shape and diameters of the humeral articular surface [12]. CT-based measurements of distal humerus morphology in healthy adults provide a basis for the design of distal humeral orthopaedic implants to ensure greater alignment with anatomical structure [30].

Ulna

The ulnar greater sigmoid notch possesses a "coverage angle" that includes both bone and cartilage contributions [1].

Radius

The radial head is a component of the integrated anatomy and biomechanics of the forearm unit, working with the interosseous membrane and distal radioulnar joint to provide longitudinal stability [14]. Restoration of anatomic radial head height is critical when performing radial head arthroplasty to maintain normal joint biomechanics [32].

Proximal Radioulnar Joint

The proximal radioulnar joint anatomy is characterized by Alpha and Beta Angles, which have a significant negative relationship [26]. The negative relationship between the Alpha Angle and the Beta Angle emphasizes the biomechanical impact of joint congruence on bony coverage in the proximal radioulnar joint [26].

Ligaments and Joint Capsule

General Stability and Function

The elbow joint possesses inherent stability derived from the interlocking shape of its articular surfaces [47]. Static joint constraint is provided by the joint capsule and collateral ligaments, while surrounding muscles generate dynamic forces to maintain stability [47]. Ligaments may function as a 'static-dynamic' stabilizer rather than acting solely as a simple static structure [63].

Medial Collateral Ligament

Considering the stabilizing function of the medial collateral ligament, the anatomic separation of its anterior bundle into two distinct bands appears artificial [54]. For tendon reconstructions of the medial ulnar collateral ligament, tightening should occur at 30 degrees of flexion rather than 90 degrees [23]. Repair of the ulnar collateral ligament using an internal brace restores resistance to valgus stress to near-intact levels without causing joint overconstraint [68].

Lateral Collateral Ligament

The lateral collateral ligament serves as a critical stabilizer for the elbow joint and the radial head during varus and external rotatory stress [69]. Within the lateral collateral ligament complex, the lateral ulnar collateral ligament contributes to, rather than acting as the major constraint against, posterolateral rotatory instability when considered alongside surrounding tissues [64].

Interosseous Membrane

The central band of the interosseous membrane functions as a ligament and acts as a secondary restraint to proximal radial migration when the radial head is intact [66]. In forearm interosseous ligament isometry studies, ligament orientation angles ranging from 9° to 38° produced significantly less suture excursion than angles of 39° [67]. Minimal suture excursion was specifically noted at ligament orientation angles of 20° [67].

Surgical and Clinical Considerations

Safe surgical procedures about the elbow require a critical appreciation of relevant neurovascular and ligamentous structures [8]. Thorough knowledge of distal biceps insertional and footprint anatomy is essential for understanding the biomechanics of rupture and reconstruction, as well as for avoiding nerve injuries [5]. Ligament-preserving approaches allow visualization of the entire joint surface and may serve as an alternative to ligament-releasing techniques [21]. The primary indication for anterior capsular release or resection is the treatment of flexion contracture caused by capsular hypertrophy in the presence of normal or near-normal joint structure [7]. Arthroscopic treatment for coronoid process nonunion facilitates the management of associated lesions, including lateral collateral ligament imbrication [76].

Muscles and Tendons

Elbow Ligaments and Tendons

The anterior bundle insertion of the medial ulnar collateral ligament complex is more elongated and distally tapered than previously described [16]. Geometric centroids of the medial ulnar collateral ligament complex footprints are predictable within 0.8 to 1.3 mm for most footprints [16]. Regarding the triceps tendon, gross measurement of the insertion overestimates and inaccurately represents the true insertional footprint compared with histologic measurement [73]. Arthroscopic double-row repair of the triceps tendon provides anatomic coverage of the triceps footprint, allowing more surface area for healing [80].

In ulnar collateral ligament reconstruction, placing a graft within the footprint of the native ulnar collateral ligament may better approximate normal joint mechanics [83]. However, the middle and distal thirds of the insertional footprint of the ulnar collateral ligament on the ulna did not significantly contribute to resistance at 5 N·m of valgus load [85]. For lateral ulnar collateral ligament tendon graft reconstruction, there is no truly isometric location for tunnels [88]. The footprints of the posterolateral ligament of the elbow have been described, and its clinical significance has been demonstrated in cases of elbow instability caused by acute ligament tears and elbow pain due to ligament enthesopathy [93].

Distal Biceps Tendon

An anatomic Footprint repair restores superior biomechanical supination strength and endurance compared to a conventional Endobutton technique in a clinical setting [84]. The single-incision arthrotunneling technique recreates the anatomic footprint and biomechanics of the native biceps and has a reduced complication profile compared to a two-incision approach [87].

The distal biceps tendon insertion footprint is on the posterior/ulnar aspect centered at approximately 30 degrees anterior to the lateral/coronal plane with the forearm fully supinated [90]. Neurovascular structures in the cubital fossa are in close proximity to the distal biceps tendon and its tuberosity insertion, and dynamic rotation significantly changes their positional relation with the tendon insertion [89].

Other Muscles and Tendons

Endoscopic proximal hamstring repair is supported by cadaveric mapping of the anatomic landscape encountered endoscopically, supporting its efficacy and safety [82]. In rotator cuff repair, margin convergence techniques with single stitch and subsequent footprint repair may have adverse effects on supraspinatus muscle properties and tensile loading on repair, increasing the risk of retear [86].

Biometric data for the pronator quadratus muscle has been detailed to support surgical procedures involving the distal forearm [91]. A map of the specific common flexor tendon origins and their sizes on the medial epicondyle, as well as their position relative to the medial collateral ligament, has been created based on anatomical measurements [92].

Neurovascular Anatomy

General Principles

Safe surgical procedures about the elbow require an appreciation of the relevant neurovascular and ligamentous structures [8]. A thorough understanding of biomechanical principles and neurological pathways is necessary for the hand surgeon [10]. Furthermore, understanding the anatomy of the radial nerve branches at the elbow is of utmost importance when devising a reconstructive strategy for upper limb paralysis [79].

Ulnar Nerve

The arcade of Struthers is a recognized point of compression and tethering, with hourglass indentation found in all nerves at this point [62]. The inferior ulnar collateral artery provided the only direct vascularization to the ulnar nerve in the region just proximal to the cubital tunnel [71]. The extrinsic vascular supply of the ulnar nerve can be preserved during anterior transposition, even after extensive mobilization of the nerve [65].

Median Nerve

A rare anatomic variation exists in which the median nerve travels in a bony canal of the distal humerus, separating from the brachial artery [78].

Vascular Anatomy

The arterial supply of the proximal ulna is relatively consistent and flows in opposite directions from 2 separate areas [72]. An aberrant osseous tunnel in the medial epicondyle may contain a notch or foramen through which the posterior inferior ulnar collateral artery and accompanying veins and nerves pass [74]. Vascular anatomy for the vascularized olecranon bone graft is consistent and flap harvest is simple and straightforward in all cadaveric specimens [70].

Surgical Considerations

The lateral approach offers simplicity of exposure with no requirement for dissection of important neurovascular structures and provides flexibility in exposure from limited to widely extensible [19]. Important neurovascular structures are in relatively close proximity to most of the described arthroscopic portals, making a careful and standardized technique mandatory to avoid injuries [20]. Magnetic resonance neurography provides anatomical correlation and pinpoints nerve pathology, thereby enhancing diagnostic confidence and guiding appropriate treatment planning [77].

Biomechanics and Function

General Principles and Methodology

Deformable mechanics examines the effect of forces and motions on internal body stresses, distinguishing intrinsic material properties from extrinsic structural properties [35]. The term "stiffness" requires an exact description of the load configuration and the precise localization and kind of deformation measured [55]. Graphical statics remains a useful tool for visualizing, understanding, and checking the actions of force groups in modern biomechanical problems, serving as an intuitive drawing method for solving plane mechanical issues [58]. In a systematic review of optical motion capture, eight studies followed International Society of Biomechanics standards for quantifying upper body kinematics [2].

Elbow Joint Biomechanics

Understanding elbow biomechanics and injury mechanisms provides valuable insight into the variations of pathology observed in complex elbow dislocations [3]. The native human elbow exhibits a load sharing ratio of 58% for the radiocapitellar joint and 42% for the ulnotrochlear joint across the functional range of flexion and forearm rotation [61]. Axial loading increases the contact area of the radiocapitellar joint [57]. The radiocapitellar joint demonstrates a high correlation between the long outer diameter of the radial head and the vertical height and anterior width of the capitellum, with no significant differences between right and left elbows [34]. The ulnar greater sigmoid notch coverage angle involves both bone and cartilage contributions, with anatomic variations requiring further biomechanical and clinical studies to determine clinical relevance [1].

Recent changes in elbow arthroplasty device design and implantation methods are driven by biomechanical and clinical outcome-based research to better reproduce elbow kinematics [56]. Conversely, the Souter-Strathclyde total elbow prosthesis exhibits biomechanical alterations predicted to explain reported relatively high rates of mechanical loosening [51]. Dynamic changes in wrist and forearm geometry observed during grasp and isometric contraction of elbow flexors are important for understanding wrist and forearm force transmission [53].

Ligamentous Biomechanics

The medial ulnar collateral ligament (MUCL) anterior bundle is the strongest component of the ligamentous complex and the primary restraint to valgus stress [34]. This bundle is subdivided into anterior and posterior bands that provide reciprocal function, with the anterior band tight in extension and the posterior band tight in flexion [34]. Detailed analysis of MUCL fibers allows for understanding its kinematic function and provides coverage area and kinematic function for each degree of motion arc, allowing selective reconstruction according to mechanism of injury [24]. The lateral ulnar collateral ligament origin center is located 10.7 mm from the lateral epicondyle and its insertion is 3.3 mm from the apex of the supinator crest [34].

Both TightRope and traditional docking ulnar collateral ligament reconstruction techniques restored native joint kinematics from 15 to 75 degrees of flexion under low loading conditions [45]. Further biomechanical and clinical studies are needed to confirm long-term outcomes for humeral ligament reconstruction using Shark Screw tendon in medial and posterolateral elbow instability [15].

Shoulder Joint Biomechanics

Patient-specific musculoskeletal modeling of shoulder joint biomechanics can contribute significantly to predicting pathology and optimizing postoperative function [39].

Throwing Biomechanics

The biomechanics of throwing in baseball and football differ significantly, leading to distinct injury patterns between the sports [17]. Professional pitchers demonstrated greater biomechanical efficiency than collegiate pitchers [59].

Common Sites of Injury

Elbow biomechanics and injury mechanisms provide insight into the pathology variations observed in complex elbow dislocations [3]. The ulnar greater sigmoid notch coverage angle involves contributions from both bone and cartilage [1]. In the forearm, the structure operates as a series of interconnected parts where damage to one component can affect stability in multiple areas [28]. Physicians need a holistic understanding of these components to quickly diagnose proper injury patterns before the condition worsens [28]. Injury to the interosseous membrane contributes more to the disruption of the normal distribution of axial loads across the elbow than injury to the distal radioulnar joint [44].

Medial Elbow Structures: Detailed analysis of the medial ulnar collateral ligament fibers allows for further understanding of its kinematic function [24]. The anterior bundle of this ligament exhibits heterogeneity in injuries, with a variety of injury configurations and chronic attritional damage observed in patients undergoing reconstruction [48]. For small subtype 2 posteromedial rotatory incongruity fractures, ligamentous repair alone may not reliably restore kinematics [33]. Larger posteromedial rotatory incongruity fractures should ideally have fragments fixed or reconstructed [33].

Distal Biceps and Soft Tissue: Thorough knowledge of distal biceps insertional and footprint anatomy is essential for understanding the biomechanics of rupture and reconstruction and for avoiding nerve injuries [5]. Detailed anatomic knowledge is also important for surgical procedures involving upper extremity trauma exposures and soft tissue coverage [6].

Pediatric and Humeral Injuries: Five distinct fracture patterns of the humeral medial epicondyle in children and adolescents are identifiable on plain radiographs and are associated with specific injury mechanisms [36, 37]. Identification of these humeral medial epicondyle injury patterns is a key first step in understanding the variability in clinical outcomes with different management strategies for medial elbow injuries [43]. Traumatic subluxation of the radial head is a rather frequent injury in young children [40].

Sport-Specific Biomechanics: The biomechanics of throwing in baseball and football differ significantly, leading to distinct injury patterns between the two sports [17].

Surgical Anatomy

Bony Anatomy and Articular Surface

The ulnar greater sigmoid notch coverage angle involves contributions from both bone and cartilage, as demonstrated in an MRI anatomic study of 78 elbows [1]. Cartilage thickness of the distal humerus is not uniform [12]. This non-uniform cartilage thickness modifies the morphologic shape and diameters of the humeral articular surface [12].

Neurovascular and Ligamentous Structures

Important neurovascular structures are in relatively close proximity to most described arthroscopic portals, making a careful and standardized technique mandatory to avoid injuries [20]. Penetration of the posterior humeral cortex at the suprapectoral location results in proximity to the axillary nerve and should be avoided [42].

Surgical Approaches and Exposure

The primary indication for an anterior deep approach is to perform an anterior capsular release or resection to treat a flexion contracture caused by capsular hypertrophy with a normal or near-normal joint structure [7]. A combination of two ligament-preserving approaches enables viewing the entirety of the joint surface and may represent an alternative to ligament-releasing approaches [21]. A mastered technique allows exploring the total joint space while minimizing peripheral tissue morbidity and risks to noble structures [38].

Detailed knowledge about the anatomical situation in the areas of pin implantation is of great importance for unilateral external fixation in the upper limb [25]. In the upper limb, the anatomical base of pin placement is of paramount importance [52]. A technique exists to safely identify the entry point of the canal and avoid complications associated with perforation of the ulnar cortex, allowing for accurate placement of the ulnar component [49].

Biomechanical and Clinical Relevance

The surgical management of proximal ulna fractures must take the complex biomechanics of the elbow joint into account [22]. A thorough understanding of biomechanical principles and neurological pathways is necessary for the hand surgeon in upper limb spasticity management [10].

Key Evidence

• [L5] Biomechanical and clinical studies are needed to understand the true clinical relevance of these anatomic variations. [1] (10.1016/j.jse.2015.06.006)
• [L4] Eight studies followed International Society of Biomechanics standards for quantifying upper body kinematics. [2] (10.1016/j.jelekin.2018.02.011)
• [L4] Understanding elbow biomechanics and the injury mechanism provides valuable insight into the variations of pathology that may be observed. [3] (10.5435/jaaos-d-14-00023)
• [L4] Thorough knowledge of the anatomy is essential for the surgeon in order to understand the biomechanics of rupture and reconstruction of the distal biceps tendon and to avoid injuries of the nerves. [5] (10.1007/s00167-014-3322-9)
• [L5] The issue emphasizes the importance of preparation and detailed anatomic knowledge in surgical procedures for upper extremity trauma, providing comprehensive descriptions of exposures and coverage with clinical examples. [6] (10.1016/j.hcl.2014.08.004)
• [L5] The primary indication is to perform an anterior capsular release or resection to treat a flexion contracture caused by capsular hypertrophy with a normal or near-normal joint structure. [7] (10.1097/00132589-200203000-00005)
• [L5] An appreciation of the relevant neurovascular and ligamentous structures is critical to safely performing surgical procedures about the elbow. [8] (10.5435/00124635-200905000-00007)
• [L5] Understanding normal and degenerative anatomy is necessary to restore joint function and prevent complications such as glenoid loosening or cuff failure. [9] (10.1302/2058-5241.6.210014)
• [L5] A thorough understanding of biomechanical principles and neurological pathways is necessary for the hand surgeon. [10] (10.1177/17531934261434453)
• [L4] Cartilage thickness is not uniform and modifies the morphologic shape and diameters of the humeral articular surface. [12] (10.1016/j.jse.2016.10.012)
• [L5] This article discusses the basic anatomy of the elbow and the biomechanics of this joint, noting that a combination of bony articulation and soft-tissue stabilizers accounts for the elbow's stability and complex kinematics. [13] (10.1016/j.csm.2004.06.008)
• [L4] The review outlines the integrated anatomy and biomechanics of the forearm unit, emphasizing that longitudinal stability relies on the radial head, interosseous membrane, and distal radioulnar joint working together, and discusses current diagnostic and treatment options. [14] (10.1111/j.1758-5740.2012.00207.x)
• [L5] Further biomechanical and clinical studies are needed to confirm long-term outcomes. [15] (10.1016/j.jseint.2026.101786)
• [L5] The study quantified the 3D anatomy of the medial ulnar collateral ligament complex, revealing that the anterior bundle insertion is more elongated and distally tapered than previously described, with geometric centroids predictable within 0.8 to 1.3 mm for most footprints. [16] (10.1177/2325967118762751)
• [L5] The biomechanics of throwing in baseball and football differ significantly, leading to distinct injury patterns between sports. [17] (10.1177/23259671251407244)
• [Paper] The authors present an excellent overview of research relating to the biology and biomechanics of fracture healing to support their argument for the beneficial effects of movement at the fracture site produced by functional bracing. [18] (10.1016/0020-1383(96)89814-7)
• [L5] The lateral approach offers simplicity of exposure with no requirement for dissection of important neurovascular structures and provides flexibility in exposure from limited to widely extensible. [19] (10.1097/00132589-200203000-00004)
• [L5] Important neurovascular structures are in relatively close proximity to most of the described portals, making a careful and standardized technique mandatory to avoid injuries. [20] (10.1016/s1058-2746(09)80110-9)
• [L5] A combination of these two ligament-preserving approaches enables viewing the entirety of the joint surface and may represent an alternative to ligament-releasing approaches. [21] (10.1016/j.jse.2022.01.013)
• [L5] The aim of this review is to illustrate the proper surgical management of proximal ulna fractures using modern osteosynthetic implants and novel techniques while taking the complex biomechanics of the elbow joint into account. [22] (10.1302/2058-5241.4.180022)
• [L5] The article reviews the anatomy and biomechanics of soft tissue stabilizers, emphasizing that the anterior bundle of the medial ulnar collateral ligament is the primary restraint to valgus loads and that tendon reconstructions should be tightened at 30 degrees of flexion rather than 90 degrees. [23] (10.1016/j.jhsa.2019.10.034)
• [L5] Detailed analysis of the fibers of the MUCL allows for further understanding of its kinematic function. [24] (10.1177/2325967118762750)
• [L5] Detailed knowledge about the anatomical situation in the areas of pin implantation is of great importance. [25] (10.1016/s0020-1383(99)00258-2)
• [L4] This study describes anatomical structures of the PRUJ and highlights a significant negative relationship between the Alpha Angle and the Beta Angle, emphasizing the biomechanical impact of joint congruence on bony coverage. [26] (10.1016/j.xrrt.2026.100695)
• [L5] This is the first anatomical study clarifying the origin of the vortical movement of the elbow due to the helical path of the distal humeral groove based on a statistical shape model of the humerus. [27] (10.1016/j.jse.2025.08.018)
• [Paper] The forearm operates as a series of interconnected parts where damage to one can affect stability in multiple areas, and physicians need a holistic understanding of these components to quickly diagnose the proper injury patterns before the condition worsens. [28] (10.1016/j.hcl.2020.06.001)
• [L4] The findings provide a basis for the design of distal humeral orthopaedic implants, ensuring greater alignment with the anatomical structure of the distal humerus and improved surgical outcomes. [30] (10.1186/s12891-024-07858-4)
• [L5] Restoration of the anatomic radial head height is critical when performing radial head arthroplasty to maintain normal joint biomechanics. [32] (10.1016/j.jhsa.2021.11.006)
• [L5] For small subtype 2 fractures, ligamentous repair alone may not reliably restore kinematics, and larger fractures should ideally have fragments fixed or reconstructed. [33] (10.1016/j.jse.2018.02.018)
• [L4] This large cohort confirmed five distinct fracture patterns that are identifiable on plain radiographs and are associated with specific injury mechanisms. [36] (10.1177/2325967126s00493)
• [L4] This large cohort confirmed five distinct fracture patterns that are identifiable on plain radiographs and are associated with specific injury mechanisms. [37] (10.1177/2325967126s00189)
• [L5] A mastered technique allows exploring the total joint space while minimizing peripheral tissue morbidity and risks to noble structures. [38] (10.1016/j.main.2006.07.020)
• [L5] Patient-specific musculoskeletal modeling of shoulder joint biomechanics can contribute significantly to predicting pathology and optimizing postoperative function. [39] (10.1016/j.jseint.2024.04.006)
• [L4] The injury is apparently a rather frequent one and a description should be available to all orthopaedic surgeons. [40] (10.2106/00004623-195436030-00018)
• [L5] In a cadaveric model, penetration of the posterior humeral cortex at the suprapectoral location results in proximity to the axillary nerve and should be avoided. [42] (10.1016/j.jse.2014.06.038)
• [L4] As the treatment rationale for ME injuries is often predicated on restoring elbow biomechanics through anatomical restoration of the UCL, identification of these injury patterns is potentially a key first step in understanding the variability in clinical outcomes with different management strategies for medial elbow injuries. [43] (10.1177/2325967126s00151)
• [L5] Injury to the interosseous membrane contributes more to the disruption of the normal distribution of axial loads across the elbow than injury to the distal radioulnar joint. [44] (10.1016/j.jse.2018.07.016)
• [L5] Both the TR and DO techniques restored native joint kinematics from 15 to 75 degrees of flexion under low loading conditions. [45] (10.1177/0363546513482567)
• [Paper] The elbow joint is inherently stable because of the interlocking shape of its articular surfaces, with the joint capsule and collateral ligaments providing static joint constraint and surrounding muscles producing dynamic forces. [47] (10.1016/s1058-2746(09)80053-0)
• [L4] This study shows the heterogeneity of anterior bundle injuries in patients undergoing UCL reconstruction, with a variety of injury configurations and chronic attritional damage observed. [48] (10.1016/j.jse.2019.01.017)
• [L5] We feel this technique can be utilized to safely identify the entry point of the canal and avoid complications associated with perforation of the ulnar cortex and allow for accurate placement of the ulnar component. [49] (10.1097/bte.0000000000000042)
• [L5] These biomechanical alterations are predicted to explain the reported relatively high rates of mechanical loosening with this prosthesis. [51] (10.1016/s1058-2746(00)90041-7)
• [Paper] In the upper limb the anatomical base of pin placement is of paramount importance. [52] (10.1016/s0020-1383(99)00255-7)
• [L4] The dynamic changes in wrist and forearm geometry observed in this study are important for an understanding of wrist and forearm force transmission. [53] (10.1016/0363-5023(92)90320-o)
• [L5] The anatomic separation of the anterior bundle into two different bands seems to be artificial, when the stabilizing function of the ligament is considered. [54] (10.1016/s1058-2746(98)90021-0)
• [Paper] The term "Stiffness" of a structure always requires an exact description of the load configuration and the exact localization and kind of deformation measured. [55] (10.1016/s0020-1383(00)80040-6)
• [L5] Recent changes in device design and implantation methods are driven by biomechanical and clinical outcome-based research to better reproduce elbow kinematics, resulting in more durable and long-lasting joint replacement procedures. [56] (10.1302/2058-5241.2.160064)
• [L5] Axial loading increases the contact area of the radiocapitellar joint. [57] (10.1016/j.jse.2020.08.042)
• [Paper] Graphical statics is an almost forgotten, intuitive drawing method for solving plane mechanical problems that remains a useful tool for visualizing, understanding and checking the actions of force groups occurring in modern biomechanical problems. [58] (10.1016/s0020-1383(00)80041-8)
• [L4] Professional pitchers had greater biomechanical efficiency than collegiate pitchers. [59] (10.1177/03635465221119194)
• [L5] The study establishes a load sharing ratio of 58%:42% for the radiocapitellar and ulnotrochlear joints, respectively, and is the first to comprehensively evaluate loading mechanics across both native joints simultaneously throughout the entire functional range of elbow flexion and forearm rotation. [61] (10.1177/1758573220961025)
• [L5] The anatomy is clinically relevant because the site is recognized as a point of compression and tethering, with hourglass indentation found in all nerves at this point. [62] (10.1016/j.jhsa.2003.12.014)
• [L5] Based on these perspectives, ligaments could function as a 'static-dynamic' stabilizer rather than a simple static one. [63] (10.1016/j.jseint.2024.01.006)
• [L5] The authors believe that the LUCL contributes to rather than is a major constraint to the posterolateral rotatory instability as part of the lateral collateral ligament complex with the surrounding tissues. [64] (10.1016/s1058-2746(99)90102-7)
• [L5] On the basis of these anatomic dissections, it is suggested that the extrinsic vascular supply can be preserved during anterior transposition of the ulnar nerve, even after extensive mobilization of the nerve. [65] (10.1016/0363-5023(93)90086-i)
• [L5] The central band functions as a ligament and serves as a secondary restraint to proximal migration of the radius when the radial head is intact. [66] (10.1016/s0363-5023(97)80036-6)
• [L5] Ligament orientation angles from 9° to 38° produced significantly less suture excursion than angles of 39°, with minimal suture excursion noted at angles of 20°. [67] (10.1053/jhsu.1999.0538)
• [L5] The procedure did not lead to joint overconstraint while also returning the ligament to near-intact levels of resisting valgus stress. [68] (10.1177/23259671221134829)
• [Paper] The anatomy of LCL was described, and the ligament was shown to be an important stabilizer of the elbow joint and the radial head, during varus and external rotatory stress. [69] (10.1016/s1058-2746(95)80082-4)
• [L5] Vascular anatomy is consistent and flap harvest is simple and straightforward in all cadaveric specimens. [70] (10.1016/j.jhsa.2019.05.014)
• [L5] The inferior ulnar collateral artery provided the only direct vascularization to the nerve in the region just proximal to the cubital tunnel. [71] (10.1016/s1058-2746(99)90048-4)
• [L5] The arterial supply of the proximal ulna is relatively consistent and flows in opposite directions from the 2 separate areas. [72] (10.1016/j.jhsa.2011.02.011)
• [L5] Gross measurement of the triceps tendon insertion overestimates and inaccurately represents the true insertional footprint compared with histologic measurement. [73] (10.1016/j.jhsa.2021.05.003)
• [L5] Our anatomic dissection demonstrated a notch or foramen through which the posterior inferior ulnar collateral artery and accompanying veins and nerves passed. [74] (10.1016/s1058-2746(99)90084-8)
• [L5] The technique allows for both the diagnosis and management of associated lesions, including lateral collateral ligament imbrication or the removal of loose bodies. [76] (10.1016/j.eats.2025.103668)
• [Paper] Its main benefit is providing anatomical correlation and pinpointing nerve pathology, thereby enhancing diagnostic confidence and guiding appropriate treatment planning. [77] (10.1177/23259671251400763)
• [L5] We report a rare anatomic variation in which the median nerve travels in a bony canal of the distal humerus, separating from the brachial artery. [78] (10.1016/j.jhsa.2004.05.018)
• [L5] Understanding the anatomy of the radial nerve branches at the elbow is of utmost importance when devising a reconstructive strategy for upper limb paralysis. [79] (10.1016/j.jhsa.2023.11.021)
• [L5] The technique provides anatomic coverage of the triceps footprint, allowing more surface area for healing. [80] (10.1016/j.eats.2024.103129)
• [L5] This account of the physiology of joints is drawn largely from previously published accounts and brings the material up-to-date with certain relatively recent findings, omitting unverified or controversial studies. [81] (10.2106/00004623-196345050-00015)
• [L5] This cadaveric study maps the anatomic landscape encountered endoscopically and supports the efficacy and safety of endoscopic proximal hamstring repair. [82] (10.1177/2325967118s00147)
• [L5] By placing the graft within the footprint of the native UCL, this reconstruction may better approximate normal joint mechanics. [83] (10.1016/j.jse.2012.12.023)
• [L3] This study is the first to demonstrate that an anatomic Footprint repair restores superior biomechanical supination strength and endurance compared to a conventional Endobutton technique in a clinical setting. [84] (10.1177/1758573218815312)
• [L5] The middle and distal thirds of the insertional footprint of the UCL on the ulna did not significantly contribute to resistance at 5 N·m of valgus load. [85] (10.1177/2325967118825294)
• [L5] MC techniques with single stitch and subsequent footprint repair may have adverse effects on muscle properties and tensile loading on repair, increasing the risk of retear of repairs. [86] (10.1371/journal.pone.0162110)
• [L5] The single-incision arthrotunneling technique is a safe and effective repair that recreates the anatomic footprint and biomechanics of the native biceps and has a reduced complication profile compared to a two-incision approach. [87] (10.1177/17585732211034818)
• [L5] There is no truly isometric location for LUCL tendon graft reconstruction tunnels. [88] (10.1177/0363546509346049)
• [L5] Neurovascular structures in the cubital fossa are in close proximity to the distal biceps tendon and its tuberosity insertion, and dynamic rotation significantly changes their positional relation with the tendon insertion. [89] (10.1136/jisakos-2019-000326)
• [L5] This study is the first to quantitatively describe the angular location of the radial tuberosity and the relationship of the distal biceps tendon on the tuberosity, finding the insertion footprint is on the posterior/ulnar aspect centered at approximately 30 degrees anterior to the lateral/coronal plane with the forearm fully supinated. [90] (10.1016/j.jse.2007.05.005)
• [L5] This study provides valuable biometric data for surgical procedures involving the distal forearm by detailing the anatomy of the pronator quadratus muscle. [91] (10.1186/s12891-025-08914-3)
• [L5] The measurements found have allowed the creation of a map of the specific common flexor tendon origins and their sizes on the medial epicondyle, as well as their position relative to the MCL. [92] (10.1016/j.jhsa.2024.04.008)
• [L4] Its footprints were described, and its clinical significance was demonstrated in cases of elbow instability caused by acute ligament tears and elbow pain due to ligament enthesopathy. [93] (10.1016/j.jse.2023.08.033)

See Also

• Radial head arthroplasty
• Elbow Instability
• Elbow Arthroplasty

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