伸肌腱修复

This is the clinical evidence summary written for health professionals. It is technical, and it lists the research this page was built from. You do not need to read it to understand your treatment or to make a decision about it.

Anatomy & Pathophysiology¶

General Hand Architecture¶

• The hand is composed of 19 bones, 17 articulations, and 19 muscles situated entirely within the hand [2].
• Approximately the same number of tendons activated by forearm muscles are present in the hand [2].
• The hand functions efficiently only if the proximal joints of the limb are stable and yet mobile [2].
• The dorsal aspect of the hand is convex, while the anterior, palmar, or volar aspect is concave [2].
• The palmar surface is the functional surface of the hand, while the dorsal surface is usually visible and aesthetically important [2].
• The thumb has a more proximal and lateral position than the four fingers, allowing movement inward and outward from the palm [2].
• When fingers are extended and separated, their tips lie on the circumference of a circle whose center is the head of the third metacarpal [2].

Metacarpal and Longitudinal Arch Anatomy¶

• The metacarpal arch possesses adaptability due to the mobility of the peripheral metacarpals [7].
• The index metacarpal is the most firmly fixed of the metacarpals [7].
• The ring metacarpal has approximately 10 degrees of mobility in flexion and extension [7].
• The fifth metacarpal has a range of flexion–extension of approximately 20 degrees [7].
• The second to fifth metacarpals are bound together by the deep transverse intermetacarpal ligament, also known as the interglenoid ligament [7].
• The interglenoid ligament ties together the anterior glenoid ligaments of the metacarpophalangeal articulations, known as volar plates [7].
• The metacarpophalangeal joints serve as the keystones of the longitudinal arches of the hand [7].
• The volar plates prevent hyperextension at the metacarpophalangeal joints [7].
• The sagittal bands of the extensor apparatus insert onto the volar plate [7].
• The first annular segment of the pulley of the flexor tendons inserts onto the volar plate [7].

Extensor Tendon and Intrinsic Muscle Anatomy¶

• There are seven interosseous muscles in the hand, consisting of four dorsal and three volar muscles [4].
• The dorsal interossei are abductors, while the volar interossei are adductors [4].
• The middle finger has two dorsal interossei and no volar interossei because the central axis of the hand lies within it [4].
• Each dorsal interosseous muscle, with the exception of the third, has two muscle heads: a superficial head and a deep head [4].
• The superficial head of the dorsal interosseous muscles abducts and weakly flexes the proximal phalanx [4].
• The deep head of the dorsal interosseous muscles forms the lateral band at the level of the metacarpophalangeal joint [4].
• The deep head of the dorsal interosseous muscles flexes and weakly abducts the proximal phalanx while extending the middle and distal phalanges [4].
• Transverse fibers arch dorsally from each lateral band to join over the dorsum of the finger, flexing the proximal phalanx [4].
• Oblique or spiral fibers from the lateral bands insert onto the lateral tubercles at the base of the middle phalanx to extend the middle phalanx [4].
• The lateral bands are joined by the lateral slips of the extensor tendon to form the conjoined lateral band [4].
• The two conjoined lateral bands unite at the distal third of the middle phalanx to form the terminal tendon [4].
• The terminal tendon inserts at the base of the distal phalanx to extend it [4].
• The volar interossei have only one muscle head and do not insert onto the proximal phalanx [4].
• The flexor digiti quinti brevis forms the ulnar lateral band of the little finger [4].

Cutaneous and Vascular Anatomy¶

• The dorsal cutaneous unit extends from the wrist to the proximal interphalangeal joints of the fingers and the interphalangeal joint of the thumb [3].
• The dorsal covering of the interphalangeal articulations forms a unique cutaneous unit characterized by considerable excess of skin when digits are in extension [3].
• The palmar integument is subdivided into two zones by the oppositional crease of the thumb [3].
• The skin of the radial portion of the palm covers the thenar eminence and is relatively well vascularized and mobile [3].
• The skin of the ulnar and distal portion of the palm covers the hypothenar eminence and has poor mobility [3].
• The central triangular part of the palm has fixed, poorly vascularized skin that covers the superficial palmar aponeurosis [3].
• Incisions made along the sides of the diamond-shaped cutaneous contact zones in flexed digits present a minimal chance of retraction [3].
• The princeps pollicis artery is the terminal branch of the radial artery that crosses the first intermetacarpal space [8].
• The princeps pollicis artery runs along the ulnar side of the first metacarpal bone and along the volar surface of the adductor muscle [8].
• The princeps pollicis artery divides into two terminal rami, the collateral palmar arteries of the thumb, at the level of the metacarpophalangeal joint flexion crease [8].
• Only 15% of anatomical dissections of the palmar arteries of the thumb fall into the classical "typical" category [8].
• In the second segment of the thumb, the ulnar collateral artery is often easier to dissect than the radial collateral artery [8].
• A subtendinous anastomosis at the level of the neck of the first phalanx acts as a moderator between the two collateral arteries [8].
• The dorsal arteries of the thumb originate from palmar arteries at the level of the first metacarpal and head distally on the side of the two distal phalanges [8].

Investigations¶

• Clinical evaluation of the injured or dysfunctional hand and wrist requires combining patient history with a careful physical examination to pinpoint or narrow the scope of possible pathologic processes [1].
• Diagnostic tests such as imaging and serum laboratory studies are useful in determining pathology but can be expensive, time consuming, and often nonspecific [1].
• A careful physical examination is essential to direct care and future testing if indicated [1].
• A systematic method to approaching the physical examination of the hand and wrist is essential due to the number of structures in a small space [1].
• An 8-MHz Doppler tone assessment may be used to identify superficially displaced neurovascular bundles when Dupuytren cords lie beneath soft fleshy prominences [11].
• False-negatives are possible with 8-MHz Doppler tone assessment for identifying neurovascular bundles [11].
• Doppler imaging is a promising improvement for identifying structures, but higher resolution imaging technology is needed [11].
• MR assessment of Dupuytren’s disease is hindered by the resolution of current equipment, orientation issues due to multiplanar deformities of the fingers, and lack of intraoperative availability [11].
• MRI is probably most useful in identifying additional pathology such as flexor tendon bowstringing [11].
• MRI may be helpful in providing a quantitative noninvasive measure of cellularity of affected areas, which is an index of biologic activity [11].
• The potential staging tool of MRI for measuring cellularity has not been investigated yet on a large scale [11].

References¶

[1] Orthopaedic Knowledge Update 13 Ebook Without Multimedia. Anatomy, Evaluation, Clinical Examination, and Imaging > Evaluation and Clinical Examination: Current Concepts.

[2] Exam Of The Hand Wrist 2Ed. INTRODUCTION.

[3] Exam Of The Hand Wrist 2Ed. Functional cutaneous units.

[4] Green S Operative Hand Surgery. Interosseous and Hypothenar Muscles.

[7] Exam Of The Hand Wrist 2Ed. The arches of the hand > The metacarpal arch.

[8] Exam Of The Hand Wrist 2Ed. Techniques of investigation of the arterial supply by J P Melki > Vascularization of the thumb > Palmar aspect.

[11] Dupuytren S Disease And Related Hyperproliferative Disorders. 54. The Future of Dupuytren’s Research and Treatment > 54.4 Mechanical Measurements and Procedures > 54.4.4 Imaging.