Extensor carpi radialis brevis

The flexor tendons can be damaged by a deep cut (a serious cut can also damage surrounding structures such as nerves and blood vessels). In many cases, damage that appears simple when viewed from the outside turns out to be more complex when viewed from the inside. A serious cut that injures the tendon will mean that bending the finger(s) will be impossible.

Flexor tendon injuries are a traumatic condition classified by the zone of injury (zone 1 distal to the flexor digitorum superficialis insertion, zone 2 from the flexor digitorum superficialis to the distal palmar crease, zone 3 to the palm, zone 4 to the carpal tunnel, zone 5 to the carpal tunnel). wrist to forearm).

Damage zones

• The basic concepts in restoration are the same for different zones.
• The location of the injury directly affects the healing potential.

Tendons that may be affected include:

• Flexor pollicis longus (flexion of the tip of the thumb).
• Flexor digitorum profundus (finger flexion).
• Flexor digitorum superficialis (flexion of the middle joint of each finger).
• Flexor carpi ulnaris.
• Flexor carpi radialis.

Diagnostic procedures

X-ray - may reveal a fracture associated with the injury. Ultrasound examination (ultrasound) - used if deep cuts are suspected.

Evaluation of results

• Grip strength assessment.
• DASH - Disabilities of the Shoulder and Arm.
• Goniometer measurements.

Objective examination

• Observe the resting position of your hand and evaluate the position of your fingers.
• Note that signs of malalignment may indicate an underlying fracture.
• Assess the integrity of the skin, because... this will help localize potential sites of tendon injury.
• Look for evidence of traumatic arthrotomy.

Range of motion assessment

• Passive flexion and extension of the wrist allows you to evaluate the effect of tenodesis.
• Typically, wrist extension results in passive flexion of the fingers at the metacarpophalangeal, proximal interphalangeal, and distal interphalangeal joints.
• The combination of proximal interphalangeal or distal interphalangeal joint extension with wrist extension indicates a flexor tendon tear.
• Active flexion of the proximal interphalangeal and distal interphalangeal joints is tested in isolation for each finger.

Neurovascular assessment

This is an important aspect of assessment given the very close proximity of the flexor tendons to the neurovascular bundles of the fingers.

Participation in sports[edit | edit code]

As wrist flexors, these muscles perform both static (hammer throwing, fencing, tennis) and dynamic work [handball, javelin throwing, discus throwing, shot put, weightlifting, kayaking, gymnastics, wrestling and swimming (freestyle, butterfly, back crawl)]. The flexor carpi radialis is additionally involved in radial abduction at the end of the throw phase of discus throwing and the push phase of breaststroke. As a weak flexor of the forearm, these muscles participate in the contraction of the main flexors (biceps brachii, brachialis, brachioradialis) in the following sports: rock climbing, gymnastics (pull-ups on the bar), pole vaulting, boxing, handball (forearm throw without return) arms), weightlifting, rowing, kayaking, luge, archery, swimming (all types), cycling (sprint), freestyle wrestling, judo and fencing. The flexor carpi radialis additionally performs pronation of the forearm, helping the pronator teres during javelin throwing, all types of wrestling (freestyle, judo), fencing, swimming (breaststroke, freestyle, butterfly) and rock climbing.

Surgical treatment (tendon repair)

Cut tendons do not heal on their own; tension in the tendon causes the cut ends to separate, sometimes by several centimeters. Without surgery, there is no prospect of regaining the movements that have been lost. Recovery can be done under general or local anesthesia (injection of local anesthetic into the shoulder). The wound is widened so that the cut ends of the tendon can be found and connected with sutures. At the end of the operation, the arm and forearm are immobilized in a plaster cast over the bandages, with the wrist and fingers in a slightly flexed position to protect the surgical site.

Extensor carpi radialis longus

The extensor carpi radialis longus is a muscle located in the posterior compartment of the forearm. It is partially overlapped by the brachioradialis muscle, and these muscles are often fused together. As the name indicates, it is the extensor carpi muscle that is palpated below and posterior to the elbow.

Structure

The extensor carpi radialis longus muscle is a fusiform muscle that forms a flattened tendon that passes distally over the lateral surface of the radius. In the lower third of the forearm, the tendon of the muscle, together with the tendon of the short extensor carpi radialis, is intersected by the tendons of the abductor pollicis brevis and extensor pollicis brevis. The tendons of the extensor carpi radialis longus and brevis extend deeper than the extensor retinaculum in the common synovial sheath. Together they run in a groove on the posterior surface of the styloid process of the radius. [1]

Start

The anterior surface of the lower third of the lateral epicondylar crest of the humerus and the adjacent interosseous membrane. Sometimes there may be attachment to the lateral epicondyle by the common extensor tendon. [1]

Attachment

Posterior surface of the base of the second metacarpal bone. [1]

Innervation

Radial nerve (roots C6 and C7) from the posterior bundle of the brachial plexus. [1]

Blood supply

Radial artery [1]

Function

The extensor carpi radialis longus, together with the extensor carpi radialis brevis, performs extension and abduction (radial deviation) of the wrist. In addition, the extensor carpi radialis longus can participate in flexion of the elbow joint and is active during clenching of the hand into a fist. [1]

Clinical relevance

The extensor carpi radialis longus muscle is one of the three major extensor muscles of the wrist. Is the most effective wrist extensor when the elbow is extended and when radial deviation is balanced by the primary muscle of ulnar deviation, the extensor carpi ulnaris. Functionally, the wrist extensors are actively involved in grasping movements along with the extensor carpi ulnaris. In an extended position of the wrist, flexion of the wrist by the superficial and deep flexor digitorum muscles is impossible, so these muscles act on the fingers. If the wrist is allowed to flex, the flexor tendons cannot shorten enough to effectively move the interphalangeal joints. This is how a state of active deficiency manifests itself.

Damage to the radial nerve leads to wrist extensor paralysis. This, in turn, leads to a decrease in grip strength. However, if the wrist is locked in extension, the flexor digitorum superficialis and flexor digitorum profundus tendons act on the fingers and functional grip can be achieved. [1]

Crossover syndrome is a bursitis that occurs at the intersection of the abductor pollicis longus and extensor pollicis brevis tendons over the extensor carpi radialis longus tendons proximal to the extensor retinaculum. The cause may be friction at the intersection or tenosynovitis of the two extensor tendons in their synovial sheath. This leads to pain, swelling and crunching. This condition can be mistaken for de Quervain's syndrome. It is often observed in rowers, as well as in athletes involved in sports using a racket. [2]

Extensor carpi radialis longus trigger points

Location of trigger points

• TT1 - 1-2 cm distal from the head of the radius, approximately at the height of the trigger point of the brachioradialis muscle.

Referred pain

• External epicondyle;
• The radial half of the wrist and the back of the hand in the region of the II-III metacarpal bones.

Consequences of weakness and tension

Consequences of extensor carpi radialis longus weakness

Weakness in both of these muscles results in significant loss of strength in both wrist extension and radial deviation. Loss of the extensor carpi radialis brevis muscle alone results in greater impairment than the isolated loss of the extensor carpi radialis longus muscle because the former plays a larger role in wrist extension. Weakness in wrist extension creates difficulty in power gripping and pinching due to the necessary interaction between wrist extension and finger flexion. This interaction is explained later in this chapter.

Consequences of tight extensor carpi radialis longus muscle

Tightness in these two muscles is not common but results in decreased flexibility in the directions of flexion and ulnar deviation. This limitation may cause difficulty in performing certain personal care tasks that typically require ulnar wrist flexion [56].

Extensor carpi radialis longus exercises

see extensor carpi radialis longus exercises

Extensor carpi radialis longus stretch

see extensor carpi radialis longus stretch

Extensor carpi radialis longus massage

see extensor carpi radialis longus massage

Taping of the extensor carpi radialis longus muscle

Rice. 3.11. A. extensor carpi radialis longus, b. measure the tape in the extended position of the muscle, c. Toning-lowering application [Blue]. Origin at insertion point, d. Apply the tape to the tight muscle, e. completed applique

Application

• This example illustrates a tone-lowering application of the extensor carpi radialis longus muscle.
• The tape is measured from the area of ​​the 2nd metacarpal bone on the dorsum of the hand to the lateral supracondylar ridge of the humerus with the hand palmar flexed and pronated (Fig. 3.11 b).
• The beginning of the tape is attached at the attachment of the second metacarpal bone on the dorsum of the hand in the resting position (Fig. 3.11 c).
• The muscle tightens and the skin shifts. The tape is then attached with 10% tension along the muscle belly to the origin of the lateral epicondylar ridge of the humerus (Fig. 3.11 d).
• The tape is rubbed onto the tense muscle.
• In Fig. Figure 3.11 shows the completed muscle application of the extensor carpi radialis longus.

Extensor carpi radialis longus myofascial release

see MFR of extensor carpi radialis longus

Sources

1. Palastanga N, Field D, Soames R. Anatomy and human movement: structure and function. Elsevier Health Sciences; 2006.
2. Brukner P. Khan K. Clinical sports medicine. McGraw-Hill: 2006.

Physical therapy

The goal of any rehabilitation program is to provide a gradually increasing controlled stress that stimulates differential tendon gliding and controls early collagen deposition; helps to strengthen the site of the operation; avoid formation of adhesion, seam dehiscence or re-rupture. It has been shown in animal models that movement and tension ultimately increase strength. Specific programs have emerged that include a combination of passive and active exercises to restore range of motion.

Friends, on July 17 in Moscow, as part of the #RehabTeam project, Anna Ovsyannikova’s seminar “Rehabilitation of the hand after a fracture of the distal radius (fracture of the “radius in a typical place”)” will take place.” Find out more... In addition, on July 18, she will conduct a seminar “Rehabilitation of the hand after fractures of the metacarpal bones (Boxer fracture).” Find out more...

Early physical therapy and splinting after flexor tendon repair are important for

• improving tendon healing;
• increasing tensile strength;
• reducing adhesion formation;
• Early restoration of function, reduction of stiffness and deformity.

Once recovery has been optimized, the team of therapists works with the surgeon to select a rehabilitation plan that protects the injured site while still helping to maintain tendon gliding. There are 3 types of rehabilitation programs designed for repaired flexor tendons: delayed mobilization, early passive mobilization, or early active mobilization. The first part of the process is to ensure that a thorough assessment has been carried out.

Physiotherapeutic protocols

• Immobilization: Indicated for children and non-compliant patients.
• Splints/splints are applied to the wrist and metacarpophalangeal joints in a flexion position, while the interphalangeal joints are in extension.

• Early passive movement: Duran protocol: low force and low excursion; active finger extension with passive finger flexion with patient assistance and a static splint.

• Kleinert protocol: low force and low excursion; active extension of the fingers with dynamic passive flexion of the fingers using a splint.

• Mayo synergic splint: low force and high tendon excursion; active wrist movement is added, which increases the mobility of the flexor tendon to the greatest extent.

• Early active movement: Moderate strength and potentially high excursion.

• Dorsal locking splint that limits wrist extension.

• Performing “place and hold” exercises with your fingers.

It is not necessary to follow all directives exactly. Many factors influence therapeutic decisions, depending on tendon healing, the presence of swelling, and tendon adhesion. These factors can help guide the repair process and promote functional range of motion, safely mobilize the repaired tendons, and prevent dehiscence, rupture, and or adhesions.

Flexor carpi radialis and palmaris longus[edit | edit code]

Flexor carpi radialis (1) and palmaris longus (2)
Flexor carpi radialis

(
m. flexor carpi radialis
) flexes the wrist joints or causes radial abduction of the hand. In addition, like the flexor carpi ulnaris, it transmits the pull of the long extensors to the finger joints by fixing the wrist joints.

Palmaris longus muscle

(
m. palmaris lopgus
) - a very weak flexor of the forearm and a weak flexor of the wrist joints. It pulls on the palmar aponeurosis and tenses when the tips of the thumb and little finger are brought together.

Home[edit | edit code]

• Medial epicondyle of the humerus
• Fascia of the forearm

Attachment[edit | edit code]

• Flexor carpi radialis: palmar surface of the base of the second metacarpal bone, sometimes the third metacarpal bone
• Palmaris longus muscle: palmar aponeurosis

Innervation[edit | edit code]

• Flexor carpi radialis: median nerve, C6-C8
• Palmaris longus: median nerve, C7-T1

Hand therapy

The hand therapist will usually replace the plaster splint with a lightweight plastic orthosis and begin an exercise program a few days after surgery. The therapeutic program following tendon repair is extremely important and is at least as important as the surgery itself, so it is vital that you follow your therapist's instructions closely. The goal is to keep the tendon moving in the tunnel to prevent it from “sticking” to the walls of the tunnel, but to avoid damaging the repaired tendon.

The splint is usually worn for five to six weeks, after which you are allowed to gradually return to normal use of the arm. However, the tendon does not reach its full strength until three months after surgery, and its mobility may slowly improve up to six months after surgery.

Complications

• Damage to the repaired tendon. Usually this happens almost immediately, because... in the initial period, the tendon is in the most unstable state. The patient may feel a “pop” as the repaired tendon ruptures, or simply notice that the finger does not bend the way it used to bend.
• The tendon adheres to the surrounding tissue and does not slip in the canal. The fingers can only be moved with the help of the other hand (passive movement), but it does not move independently (active movement). An additional course of manual therapy may help. In some cases, surgery to release the tendon from scar tissue (tenolysis) may improve mobility, but full range of motion may not be restored.

Additional images[edit]

• Bones of the left forearm. Rear aspect.
• Bones of the left hand. Dorsal surface.
• Cross section of the middle of the forearm.
• Posterior surface of the forearm. Deep muscles.
• Transverse section of the distal ends of the radius and ulna.
• Transverse section of the wrist and fingers.
• Mucous membranes of the tendons of the dorsum of the wrist.
• Extensor carpi radialis brevis
• Extensor carpi radialis brevis
• Extensor carpi radialis brevis
• Extensor carpi radialis brevis
• Extensor carpi radialis brevis