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Soft Tissue Anatomy

Hand soft tissue anatomy: extrinsic/intrinsic muscle balance, fascial planes, neurovascular relationships & common anatomical variations.

60 citationsUpdated Oct 2026
Illustration: Soft Tissue Anatomy

Overview

A clear understanding of acetabular osseous anatomy and surrounding soft tissues is essential for the evaluation and management of related pathologies [1]. The authors propose a nomenclature for skeletal muscle injuries that integrates topographic location with histoarchitectonic features of the damage to connective tissue structures [4]. This combined approach is argued to be essential for accurate prognosis and understanding recurrence in skeletal muscle injuries [4]. Additionally, the literature reviews studies examining the viscoelastic response of connective tissue to heat, cold, and stretch [14].

Comprehensive anatomical references provide user-friendly, portable, and clinically relevant details for the upper extremity [2]. These texts offer a comprehensive overview of hand anatomy, diagnosis, and treatment principles for various disorders [22]. The chapter on hand surgery emphasizes the balance between restoring function and maintaining aesthetic appearance [22]. A comprehensive review of the anatomy of the hand and wrist includes the nail bed, skin, fascia, compartments, palmar spaces, digits, and neurovascular structures [42]. Data suggest a functional and anatomical classification of insertion sites as periarticular or extraarticular for the interosseous muscles of the hand [3].

Specific anatomical variations and surgical considerations are critical for complex procedures. The origin, insertion, and location of an unusual variation of extensor digitorum brevis manus differ from those previously reported, and with its specific anatomic features, this variation cannot be placed into current classifications [9]. The study highlights the complex innervation pattern and peculiar anatomy of branching to different thirds of the lumbrical muscle bellies [16]. These branching patterns are important for dealing with complex and deep injuries in the palmar region [16]. Findings regarding the surgical anatomy of the supraclavicular brachial plexus differ from standard illustrations and descriptions of the brachial plexus [25]. The cutaneous branch of the deep palmar artery presents several anatomical variants, but its constant existence makes it suitable for use as a pedicle for proximal hypothenar flaps [26]. The classical description of the pulley system of the thumb is not the most frequent one [30]. The fascia of the distal phalanx acts as a fibrous canopy [41]. The digital pulp is divided into proximal and distal components with distinct mobility and tethering mechanisms, and the fascia of the distal phalanx plays a role in prehension [41]. Atypical lipomas of the hand and forearm may have a more benign behavior than atypical lipomas of other anatomical sites [51]. Principles of nerve repair and reconstruction include minimizing tension and careful soft-tissue handling [52]. Treatment options for nerve defects include autograft, nerve conduit, and decellular allograft [52].

Osseous Anatomy

The long axis of the third metacarpal penetrates the dorsal surface of the capitate about its midportion [39]. Surgeons must account for notable variation in the specific location where this axis penetrates the dorsal surface of the capitate [39]. Additionally, there is notable variation in the angular relationships between the long axis of the third metacarpal and the dorsal surface of the capitate [39].

Ligaments and Joint Capsule

Finger Ligaments and Soft Tissue Structures

The anatomy and function of Cleland's ligaments are more complex than previously described [21]. These structures maintain skin stability in all positions of the finger, prevent skin bagging, protect the neurovascular bundle, and create a gliding path for the lateral slips of the extensor tendon [21]. The A1 pulley exhibits anatomic consistency regarding its length and location by means of cutaneous landmarks on the palmar surface [49]. Recent studies confirm Littler's previously depicted anatomic consistency regarding the A1 pulley [49]. This anatomic consistency is reassuring for surgical procedures based on this consistency [49].

Proximal Interphalangeal Joint (PIP)

The volar plate exhibits volar elevation during active flexion [28]. This volar elevation could provide dynamic stresses on the adjacent ligaments and contribute to the stability and smooth gliding of the joint [28]. The extensor tendon-reflecting technique revealed the greatest amount of surface for dorsal surgical approaches to the PIP joint [27]. However, nearly 50% of the proximal phalanx articular surface remained inaccessible as long as the collateral ligaments were intact during dorsal surgical approaches [27]. Findings from anatomical studies provide an anatomical basis for procedures to denervate the PIP joint [13].

Wrist and Elbow Ligaments and Capsule

The scaphotrapezial ligament consists of three distinct fascicles [44]. The scaphotrapezial ligament includes a deep fascicle that attaches 3.3 mm from the most distal point of the scaphoid [44]. The anterior part of the extensor carpi radialis brevis (ECRB) origin was delicate because it was purely tendinous [48]. The anterior part of the ECRB origin had a thin articular capsule attachment compared with the posterodistal attachment [48]. This thin articular capsule attachment at the anterior part of the ECRB origin could be an initial factor leading to the development of lateral epicondylitis [48].

Metacarpophalangeal Joint (MCP)

The dorsal triangular fibrocartilage of the metacarpophalangeal joint may stabilize the extensor tendon [50]. The dorsal triangular fibrocartilage of the metacarpophalangeal joint may form a dorsal fossa [50]. The dorsal triangular fibrocartilage of the metacarpophalangeal joint may prevent extensor tendon attrition [50]. The dorsal triangular fibrocartilage of the metacarpophalangeal joint may produce synovial fluid [50].

Muscles and Tendons

General Principles and Nomenclature

A proposed nomenclature for skeletal muscle injuries integrates topographic location with histoarchitectonic features of damage to connective tissue structures [4]. This combined approach is argued to be essential for accurate prognosis and understanding the recurrence of skeletal muscle injuries [4].

Upper Extremity and Hand Anatomy

The text Surgical Anatomy of the Hand & Upper Extremity provides comprehensive, highly detailed, and readable anatomy for the upper extremity, characterized as user-friendly, portable, and clinically relevant [2]. In the hand, insertion sites of the interosseous muscles are functionally and anatomically classified as either periarticular or extraarticular [3]. Anatomical variations present specific surgical considerations; for instance, an unusual variation of the extensor digitorum brevis manus exhibits origin, insertion, and location features that differ from previously reported characteristics and cannot be placed into current classifications [9]. Similarly, the accessory flexor pollicis longus tendon is a common anatomical variant that challenges existing anatomical knowledge and presents potential clinical implications for surgeons [20].

Elbow and wrist anatomy reveals consistent structural landmarks. The lateral triceps expansion is a consistent anatomic finding with a width approximately 70% of the width of the central triceps tendon [11]. Detailed analysis of the extensor retinaculum compartments and the 3-dimensional anatomy of septal attachments is provided in studies of the wrist [29]. In the finger, skin creases serve as surface markers to accurately locate the underlying pulley and tendon system, facilitating the planning of limited incisions in the palm and fingers [60].

Surgical access and fixation require precise knowledge of local anatomy. The extensor tendon-reflecting technique reveals the greatest amount of surface at the proximal interphalangeal joint, but nearly 50% of the proximal phalanx articular surface remains inaccessible as long as the collateral ligaments are intact [27]. The proximal limit of the germinal nail matrix is extremely close to the terminal extensor tendon bony insertion, with an average distance of 1.2 mm [23]. Regarding flexor tendon repair, findings regarding the anatomy of the flexor digitorum profundus insertion may aid anatomical attachment of the FDP tendon in the treatment of zone I injuries [7]. However, commonly available suture anchors and drill bits are suboptimal for anchoring the flexor digitorum profundus tendon to the distal phalanx of the little finger, as the drill bits are too long and may penetrate the far cortex [61].

Neurovascular Anatomy

Nerve Anatomy and Innervation

Precise anatomic knowledge of the superficial radial nerve and its branches is essential during open release procedures to prevent nerve injury [8]. A definable zone exists over the dorsal skin where no major branch of the superficial radial nerve or the dorsal branch of the ulnar nerve passes, providing a safe area for surgical incisions [15]. The deep branch of the ulnar nerve follows a specific course with a precise branching pattern and distribution [46]. The vertical distance from the pisoscaphoid line to the crossing points with metacarpals for this deep branch is approximately 4 cm [46]. Two types of muscular branches are identified for the deep branch of the ulnar nerve: trunks that innervate multiple muscles and separate branches that innervate single muscles [46]. The palmaris brevis is the only skeletal muscle innervated by the superficial branch of the ulnar nerve [47]. Findings regarding the motor branch to the fourth lumbrical serve as a guide for intraoperative localization of the 4L/3PI motor branch and may explain findings observed after distal nerve transfers [45].

Vascular Anatomy and Blood Supply

The subcutaneous tissue can be utilized as a separate flap for covering soft tissue defects of the forearm and hand [10]. The anatomy of the first dorsal interosseous muscle, specifically its vascular and nerve supply, was studied in ten fresh cadaveric hands [19]. Dissections and microangiography of the abductor digiti minimi and flexor digiti minimi brevis muscles revealed one major and two minor pedicles [37]. A nutrient vessel is often the only vessel supplying the head of the proximal phalanx [38]. Consequently, the area of the head of the proximal phalanx is particularly susceptible to vascular compromise due to its reliance on this single nutrient vessel [38].

Neurovascular Bundles and Surgical Considerations

In Dupuytren’s disease, surgeons should identify and dissect the neurovascular bundle proximally and distally throughout its course to prevent injury [24]. The dorsal nerve fascial island flap technique restores sensory function without damaging main nerves or blood vessels [5]. This flap is an optimal option for finger soft tissue defects at the distal segments [5]. Findings on the surgical anatomy of the supraclavicular brachial plexus differ from standard illustrations and descriptions of the brachial plexus [25].

Biomechanics and Function

General Biomechanical Principles

Understanding the basic science underlying hand therapy treatment techniques requires a grasp of biomechanical concepts such as stress, strain, and moments [56]. Controlled motion during early healing functions as a form of controlled stress, which can be harnessed to generate appropriate reparative tissues [17]. Research into the viscoelastic response of connective tissue examines the effects of heat, cold, and stretch [14].

Tendon and Muscle Biomechanics

Tendons with up to 60% cross-sectional area involvement may be strong enough to withstand an early active mobilization regimen, based on previous estimates of in vivo forces [6]. Normal tendon excursions of the interossei and superficial hypothenar muscles were measured in six formalin-fixed cadaveric hands [12]. The shear modulus of the first dorsal interosseous and first lumbrical muscles increases with MCP joint extension and PIP-DIP joint flexion [55]. Strain analysis serves as an effective method for evaluating the extensor mechanism, with potential for in vivo surgical applications [57].

Ligaments and Joint Stability

The estimated lengths of principal ligaments stabilizing the thumb carpometacarpal joint change substantially during thumb motions in vivo [53]. Volar elevation of the volar plate seen in active flexion provides dynamic stresses on adjacent ligaments, contributing to joint stability and smooth gliding [28]. The volar plate of the proximal interphalangeal joint exhibits three sequential phases of motion: sliding, elevating, and rolling in the recess [59].

Pulley System and Skin

The A2 and A4 pulleys are clearly the most important structures to conserve for joint motion and to reconstruct if damaged [58]. The classical description of the thumb pulley system is not the most frequent one, based on literature review and a clinical series [30]. Longitudinal extensibility of the dorsal skin of the hand generally increases from distal to proximal and from ulnar to radial [54].

Anatomical Classification

Insertion sites of the interosseous muscles of the hand can be classified functionally and anatomically as periarticular or extraarticular [3].

Common Sites of Injury

Insertion sites are functionally and anatomically classified as either periarticular or extraarticular [3]. This combined classification approach is essential for accurate prognosis and understanding recurrence [4]. Structural variations in the flexor tendon across different sections account for differences in injury susceptibility [34]. Tendon adhesions are present in the majority of trigger fingers [35].

Zone I and Distal Defects: Findings regarding anatomical attachment aid in the treatment of zone I injuries by facilitating FDP tendon repair [7]. A specific technique restores sensory function without damaging main nerves or blood vessels, making it an optimal option for finger soft tissue defects at the distal segments [5]. Based on previous estimates of in vivo forces, even tendons with up to 60% cross-sectional area involvement may be strong enough to withstand an early active mobilization regimen [6].

Palmar and Lumbrical Anatomy: The lumbrical muscle bellies exhibit a complex innervation pattern and peculiar anatomy of branching to different thirds, which are important for dealing with complex and deep injuries in the palmar region [16]. Knowledge of specific anatomy supports repair of radial SB injuries to prevent tendon instability [32].

Variants and Mechanisms: The accessory FPL tendon is a common anatomical variant that challenges existing anatomical knowledge and presents potential clinical implications for surgeons [20]. This case reaffirms the need for appreciation of the variability of hand muscles and the potential for subtle injuries [31]. Nerve damage was greatest in table saw lacerations [33].

Surgical Anatomy

General Principles

Hand surgeons must be well informed about anatomic variations of the hand to ensure comfort and safety during surgical practice [40].

Upper Extremity and Hand

The cutaneous branch of the deep palmar artery is suitable for use as a pedicle for proximal hypothenar flaps due to its constant existence, although it presents several anatomical variants [26]. The technique of dorsal nerve fascial island flap restores sensory function without damaging main nerves or blood vessels, making it an optimal option for finger soft tissue defects at the distal segments [5]. The proximal limit of the germinal matrix is extremely close to the terminal extensor tendon bony insertion, with an average distance of 1.2 mm [23].

For epidermoid cysts in the hand, the authors recommend removing the entire tumour with a careful marginal excision that includes overlying scar tissue from any previous penetrating injury to minimize recurrence [36]. Wide excision without sacrifice of function is the indicated treatment for juvenile aponeurotic fibroma of the hand [43].

Muscles and Tendons

The authors propose a nomenclature for skeletal muscle injuries that integrates topographic location with histoarchitectonic features of the damage to connective tissue structures, arguing that this combined approach is essential for accurate prognosis and understanding recurrence [4]. The lateral triceps expansion is a consistent anatomic finding with a width that is approximately 70% of the width of the central triceps tendon [11].

Joints and Innervation

These findings provide an anatomical basis for procedures to denervate the PIP joint [13].

Key Evidence

  • [Paper] The book 'Surgical Anatomy of the Hand & Upper Extremity' is described as a comprehensive, highly detailed, and readable text that provides user-friendly, portable, and clinically relevant anatomy for the upper extremity. [2] (10.1197/j.jht.2003.10.013)
  • [Paper] The data suggest a functional and anatomical classification of insertion sites as periarticular or extraarticular. [3] (10.1016/0363-5023(88)90222-5)
  • [L5] The authors propose a nomenclature for skeletal muscle injuries that integrates topographic location with histoarchitectonic features of the damage to connective tissue structures, arguing that this combined approach is essential for accurate prognosis and understanding recurrence. [4] (10.1177/2325967120909090)
  • [L4] The technique restores sensory function without damaging main nerves or blood vessels, making it an optimal option for finger soft tissue defects at the distal segments. [5] (10.1186/s13018-022-03309-9)
  • [Paper] Based on previous estimates of in vivo forces, even tendons with up to 60% cross-sectional area involvement may be strong enough to withstand an early active mobilization regimen. [6] (10.1016/s0363-5023(05)80434-4)
  • [L5] These findings may aid anatomical attachment of the FDP tendon in the treatment of zone I injuries. [7] (10.1016/j.jhsa.2014.11.004)
  • [L5] Anatomic knowledge of the course of the superficial radial nerve and its branches is important during open release for avoiding nerve injury. [8] (10.1016/j.jhsa.2013.12.004)
  • [L5] The origin, insertion, and location of the muscle differ from those previously reported; with these anatomic features, the muscle variation cannot be placed into the current classifications. [9] (10.1016/s0363-5023(98)80108-1)
  • [L5] These findings are of practical importance since the subcutaneous tissue can be used as a separate flap for covering soft tissue defects of the forearm and hand. [10] (10.1016/0266-7681(87)90011-8)
  • [L5] The lateral triceps expansion is a consistent anatomic finding with a width that is approximately 70% of the width of the central triceps tendon. [11] (10.1016/j.jse.2009.10.008)
  • [L5] The study measured normal tendon excursions of the interossei and superficial hypothenar muscles in six formalin-fixed cadaveric hands. [12] (10.1016/0266-7681(88)90170-2)
  • [L5] These findings provide an anatomical basis for procedures to denervate the PIP joint. [13] (10.1016/j.jhsa.2018.07.014)
  • [L5] The article reviews studies that examine the viscoelastic response of connective tissue to heat, cold, and stretch. [14] (10.1016/s0894-1130(98)80013-6)
  • [L5] A definable zone over the dorsal skin for surgical incisions exists where no major branch of the superficial branch of the radial nerve or dorsal branch of the ulnar nerve passes. [15] (10.1016/j.jhsa.2005.12.021)
  • [L5] The study highlights the complex innervation pattern and peculiar anatomy of branching to different thirds of the lumbrical muscle bellies, which are important for dealing with complex and deep injuries in the palmar region. [16] (10.1177/1558944720963881)
  • [L5] Controlled motion during early healing is a form of controlled stress and can be harnessed to generate appropriate reparative tissues. [17] (10.1016/j.jht.2022.12.003)
  • [L5] The anatomy of the first dorsal interosseous muscle, with particular reference to its vascular and nerve supply, was studied in ten fresh cadaveric hands. [19] (10.1016/s0363-5023(86)80027-2)
  • [L4] The accessory FPL tendon is a common anatomical variant that challenges existing anatomical knowledge and presents potential clinical implications for surgeons. [20] (10.1177/17531934251347077)
  • [L4] The anatomy and function of Cleland's ligaments is more complex than previously described, and they play an important role in maintaining skin stability in all positions of the finger, preventing skin bagging, protecting the neurovascular bundle, and creating a gliding path for the lateral slips of the extensor tendon. [21] (10.1177/1753193413511944)
  • [L5] The proximal limit of the germinal matrix is extremely close to the terminal extensor tendon bony insertion, with an average distance of 1.2 mm. [23] (10.1053/jhsu.2000.17865)
  • [L4] Surgeons should identify and dissect the neurovascular bundle proximally and distally throughout its course to prevent injury. [24] (10.1177/1753193409349855)
  • [L5] These findings differ from the standard illustrations and descriptions of the brachial plexus. [25] (10.2106/jbjs.n.00706)
  • [L5] Although it presents several anatomical variants, its constant existence makes it suitable for use as a pedicle for proximal hypothenar flaps. [26] (10.1177/1558944719895785)
  • [L5] Although the extensor tendon-reflecting technique revealed the greatest amount of surface, nearly 50% of the proximal phalanx articular surface remained inaccessible as long as the collateral ligaments were intact. [27] (10.1016/j.jhsa.2014.02.004)
  • [L4] Volar elevation of the volar plate seen in active flexion could provide dynamic stresses on the adjacent ligaments and contribute to the stability and smooth gliding of the joint. [28] (10.1016/j.jhsa.2012.03.004)
  • [Paper] This study offers detailed analysis of the extensor retinaculum compartments and 3-dimensional anatomy of the septal attachments. [29] (10.1016/j.jhsa.2006.02.026)
  • [L5] From the literature reviewed and our own series, we have found that the classical description of the pulley system is not the most frequent one. [30] (10.1177/1558944716660555fb)
  • [L5] This case reaffirms the need for appreciation of the variability of hand muscles and the potential for subtle injuries. [31] (10.1053/jhsu.1999.1078)
  • [L5] Knowledge of this anatomy supports repair of radial SB injuries to prevent tendon instability. [32] (10.1016/j.jhsa.2008.01.039)
  • [L5] Nerve damage was greatest in table saw lacerations. [33] (10.1016/j.jhsg.2025.100833)
  • [L5] This difference is attributed to variations in the structural properties of the flexor tendon in different sections. [34] (10.1177/1753193412474175)
  • [L2] Tendon adhesions are present in the majority of trigger fingers. [35] (10.1177/1753193420969293)
  • [L4] The authors recommend removing the entire tumour with a careful marginal excision that includes overlying scar tissue from any previous penetrating injury to minimize recurrence. [36] (10.1177/1753193409347509)
  • [L5] The dissections and the microangiography of the muscles revealed 1 major and 2 minor pedicles. [37] (10.1016/j.jhsa.2004.06.001)
  • [L5] This nutrient vessel is often the only vessel supplying the head of the proximal phalanx, making this area particularly susceptible to vascular compromise. [38] (10.1016/j.jhsa.2022.09.014)
  • [L4] The long axis of the MC3 penetrates the dorsal surface of the capitate about its midportion, but there is notable variation in this location as well as in the angular relationships. [39] (10.1016/j.jhsa.2024.07.008)
  • [L4] Hand surgeons should be well informed about anatomic variations of the hand to be comfortable during surgical practice. [40] (10.1007/s11552-007-9033-7)
  • [L5] The paper describes the detailed anatomy of the distal phalanx fascia and its role in prehension, noting that the fascia acts as a fibrous canopy and that the digital pulp is divided into proximal and distal components with distinct mobility and tethering mechanisms. [41] (10.2106/00004623-197557060-00009)
  • [L4] Wide excision without sacrifice of function is the indicated treatment. [43] (10.1016/s0363-5023(85)80196-9)
  • [L5] The scaphotrapezial ligament consists of three distinct fascicles, including a deep fascicle that attaches 3.3 mm from the most distal point of the scaphoid. [44] (10.1016/j.jhsa.2025.09.010)
  • [L5] These findings provide a guide for intraoperative localization of the 4L/3PI motor branch and may explain findings seen after distal nerve transfers. [45] (10.1016/j.jhsa.2024.11.023)
  • [L5] The study provides a clear description of the course, precise branching pattern, and distribution of the deep branch of the ulnar nerve, noting that the vertical distance from the pisoscaphoid line to the crossing points with metacarpals is about 4 cm and identifying two types of muscular branches: trunks innervating multiple muscles and separate branches innervating single muscles. [46] (10.1177/1753193415622188)
  • [Paper] The palmaris brevis is the only skeletal muscle to be innervated by the superficial branch of the ulnar nerve. [47] (10.1016/j.jhse.2007.04.020)
  • [L5] The anterior part of the ECRB origin was delicate because it was purely tendinous and had a thin articular capsule attachment compared with the posterodistal attachment; this thin attachment could be an initial factor leading to the development of lateral epicondylitis. [48] (10.1016/j.jhsa.2013.11.036)
  • [L5] Recent studies confirm Littler's previously depicted anatomic consistency regarding the A1 pulley, which is reassuring for surgical procedures based on this consistency. [49] (10.1016/j.jhsa.2011.03.047)
  • [L5] Possible functions include stabilization of the extensor tendon, formation of a dorsal fossa, prevention of extensor tendon attrition, and synovial fluid production. [50] (10.1016/j.jhsa.2015.03.019)
  • [L4] The results of the current series and a review of the literature suggest that atypical lipomas of the hand and forearm may have a more benign behavior than atypical lipomas of other anatomical sites. [51] (10.1016/j.jhsa.2015.12.032)
  • [L4] The estimated lengths of principal ligaments stabilizing the CMC joint change substantially during thumb motions in vivo. [53] (10.1016/j.jhsa.2010.11.007)
  • [L4] Generally, the extensibility increased from distal to proximal and from ulnar to radial. [54] (10.1177/1753193419864881)
  • [L4] The shear modulus of the FDI and FL muscles increased with MCP joint extension and PIP-DIP joint flexion. [55] (10.1016/j.jhsa.2019.01.016)
  • [Paper] This introductory article lays the foundation of biomechanical concepts such as stress, strain, and moments, which are necessary for understanding the basic science underlying hand therapy treatment techniques. [56] (10.1016/j.jht.2011.12.006)
  • [L5] Based on our experimental findings, we conclude that strain analysis is an effective method of evaluation of the extensor mechanism with potential for in vivo surgical applications. [57] (10.1016/s0363-5023(05)80439-3)
  • [L5] The A2 and A4 pulleys are clearly the most important to conserve joint motion and to reconstruct if damaged. [58] (10.1016/s0363-5023(89)80043-7)
  • [L4] The authors propose three sequential phases of volar plate motion: sliding, elevating, and rolling in the recess. [59] (10.1016/j.jhsa.2010.10.034)
  • [L5] Skin creases can be used as surface markers to accurately locate the underlying pulley and tendon system and plan for limited incisions. [60] (10.1016/j.jhsa.2011.12.036)
  • [L5] The commonly available suture anchors and drill bits are suboptimal for anchoring the flexor digitorum profundus tendon to the distal phalanx of the little finger, as the drill bits are too long and may penetrate the far cortex. [61] (10.1177/1753193411419595)

See Also

References

[1] Chapter 33 Evaluation and Management of Acetabular Fractures. 2021.

[2] Surgical Anatomy of the Hand & Upper Extremity. Journal of Hand Therapy. 2004. DOI: 10.1197/j.jht.2003.10.013

[3] Palmar plate insertions of the interosseous muscles of the hand. The Journal of Hand Surgery. 1988. DOI: 10.1016/0363-5023(88)90222-5

[4] A Histoarchitectural Approach to Skeletal Muscle Injury: Searching for a Common Nomenclature. Orthopaedic Journal of Sports Medicine. 2020. DOI: 10.1177/2325967120909090

[5] Effect of dorsal nerve fascial island flap on repairing distal soft tissue defects at the proximal segment of the index, middle, ring, and little fingers. Journal of Orthopaedic Surgery and Research. 2022. DOI: 10.1186/s13018-022-03309-9

[6] Effect of partial laceration on the structural properties of the canine FDP tendon: An in vitro study. The Journal of Hand Surgery. 1995. DOI: 10.1016/s0363-5023(05)80434-4

[7] Anatomy of the Flexor Digitorum Profundus Insertion. The Journal of Hand Surgery. 2015. DOI: 10.1016/j.jhsa.2014.11.004

[8] The Relationship of the Superficial Radial Nerve and Its Branch to the Thumb to the First Extensor Compartment. The Journal of Hand Surgery. 2014. DOI: 10.1016/j.jhsa.2013.12.004

[9] An unusual variation of extensor digitorum brevis manus: A case report and literature review. The Journal of Hand Surgery. 1998. DOI: 10.1016/s0363-5023(98)80108-1

[10] Blood supply of the subcutaneous tissue of the upper limb and its importance in the subcutaneous flap. The Journal of Hand Surgery: Journal of the British Society for Surgery of the Hand. 1987. DOI: 10.1016/0266-7681(87)90011-8

[11] Insertional anatomy of the triceps brachii tendon. Journal of Shoulder and Elbow Surgery. 2010. DOI: 10.1016/j.jse.2009.10.008

[12] Tendon excursions of the interossei and superficial hypothenar muscles: An anatomical study. The Journal of Hand Surgery: Journal of the British Society for Surgery of the Hand. 1988. DOI: 10.1016/0266-7681(88)90170-2

[13] Innervation of the Proximal Interphalangeal Joint: An Anatomical Study. The Journal of Hand Surgery. 2019. DOI: 10.1016/j.jhsa.2018.07.014

[14] Therapeutic effects of heat, cold, and stretch on connective tissue. Journal of Hand Therapy. 1998. DOI: 10.1016/s0894-1130(98)80013-6

[15] The Cutaneous Innervation of the Dorsal Hand: Detailed Anatomy With Clinical Implications. The Journal of Hand Surgery. 2006. DOI: 10.1016/j.jhsa.2005.12.021

[16] Lumbrical Muscles Neural Branching Patterns: A Cadaveric Study With Potential Clinical Implications. HAND. 2020. DOI: 10.1177/1558944720963881

[17] How controlled motion alters the biophysical properties of musculoskeletal tissue architecture. Journal of Hand Therapy. 2023. DOI: 10.1016/j.jht.2022.12.003

[19] The first dorsal interosseous muscle: An anatomic study. The Journal of Hand Surgery. 1986. DOI: 10.1016/s0363-5023(86)80027-2

[20] Accessory flexor pollicis longus tendon – a clinical and cadaveric study. Journal of Hand Surgery (European Volume). 2025. DOI: 10.1177/17531934251347077

[21] The anatomy and function of Cleland’s ligaments. Journal of Hand Surgery (European Volume). 2013. DOI: 10.1177/1753193413511944

[22] 9. Hand Surgery. 2013.

[23] Examination of the anatomic relationship of the proximal germinal nail matrix to the extensor tendon insertion. The Journal of Hand Surgery. 2000. DOI: 10.1053/jhsu.2000.17865

[24] Spiralling of the neurovascular bundle in Dupuytren’s disease. Journal of Hand Surgery (European Volume). 2009. DOI: 10.1177/1753193409349855

[25] Surgical Anatomy of the Supraclavicular Brachial Plexus. Journal of Bone and Joint Surgery. 2015. DOI: 10.2106/jbjs.n.00706

[26] The Cutaneous Branch of the Deep Palmar Artery and Blood Supply to the Proximal Hypothenar Skin: An Anatomic Research Oriented to Flap Design. HAND. 2020. DOI: 10.1177/1558944719895785

[27] Dorsal Surgical Approaches to the Proximal Interphalangeal Joint: A Comparative Anatomic Study. The Journal of Hand Surgery. 2014. DOI: 10.1016/j.jhsa.2014.02.004

[28] Biomechanical Differences of the Proximal Interphalangeal Joint Volar Plate During Active and Passive Motion: A Dynamic Ultrasonographic Study. The Journal of Hand Surgery. 2012. DOI: 10.1016/j.jhsa.2012.03.004

[29] An Anatomic and Biomechanic Study of the Wrist Extensor Retinaculum Septa and Tendon Compartments. The Journal of Hand Surgery. 2006. DOI: 10.1016/j.jhsa.2006.02.026

[30] Variations of the Pulley System of the Thumb. HAND. 2016. DOI: 10.1177/1558944716660555fb

[31] Tear of an anomalous lumbrical muscle as a source of pain in the hand. The Journal of Hand Surgery. 1999. DOI: 10.1053/jhsu.1999.1078

[32] Functional Anatomy of the Thumb Sagittal Band. The Journal of Hand Surgery. 2008. DOI: 10.1016/j.jhsa.2008.01.039

[33] More Than Epineurium Deep: Characterizing Peripheral Nerve Damage Using High-Resolution Micro-Computed Tomography for Simulated Peripheral Nerve Lacerations. Journal of Hand Surgery Global Online. 2025. DOI: 10.1016/j.jhsg.2025.100833

[34] The suture loop holding capacity of flexor digitorum profundus tendon within and outside the digital tendon sheath. Journal of Hand Surgery (European Volume). 2013. DOI: 10.1177/1753193412474175

[35] Adhesions as a component of the trigger finger: a dynamic sonographic study. Journal of Hand Surgery (European Volume). 2020. DOI: 10.1177/1753193420969293

[36] Epidermoid cysts in the hand. Journal of Hand Surgery (European Volume). 2009. DOI: 10.1177/1753193409347509

[37] The vascular anatomy of the abductor digiti minimi and the flexor digiti minimi brevis muscles. The Journal of Hand Surgery. 2005. DOI: 10.1016/j.jhsa.2004.06.001

[38] Arterial Perfusion of the Proximal Phalanx Revisited: New Insights Based on Micro-Computed Tomography. The Journal of Hand Surgery. 2024. DOI: 10.1016/j.jhsa.2022.09.014

[39] The Three-Dimensional Relationship of the Axes of the Capitate and Third Metacarpal. The Journal of Hand Surgery. 2025. DOI: 10.1016/j.jhsa.2024.07.008

[40] The Concomitant Presence of Two Anomalous Muscles in the Forearm. HAND. 2007. DOI: 10.1007/s11552-007-9033-7

[41] The fascia of the distal phalanx. The Journal of Bone & Joint Surgery. 1975. DOI: 10.2106/00004623-197557060-00009

[42] Chapter 23 Anatomy of the Hand and Wrist. 2019.

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[44] Anatomy of the Scaphotrapezial Ligament Complex and its Implications for Distal Scaphoid Resection. The Journal of Hand Surgery. 2026. DOI: 10.1016/j.jhsa.2025.09.010

[45] Anatomical Characterization of the Motor Branch to the Fourth Lumbrical: A Cadaver Study. The Journal of Hand Surgery. 2025. DOI: 10.1016/j.jhsa.2024.11.023

[46] Anatomy of the deep branch of the ulnar nerve. Journal of Hand Surgery (European Volume). 2016. DOI: 10.1177/1753193415622188

[47] The First Description of the Palmaris Brevis Muscle. Journal of Hand Surgery (European Volume). 2007. DOI: 10.1016/j.jhse.2007.04.020

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