Sprain

Japanese: 捻挫 - ねんざ（英語表記）Sprain

What kind of injury?

A typical injury occurs when a joint is forced to move beyond its physiological range of motion due to an unnatural external force. dislocation ( Dakkyu ) When there is no displacement between the bones that make up the joint, it is called a sprain, and when there is even a slight displacement, it is called a dislocation or Subluxation ( Adakkyu ) It is called.

The joints most susceptible to sprains are Ankle ( Rapid response ) However, there are many more joints in the human body than most people would imagine. Among the joints in the limbs are the shoulders, knees ( Knee ) In addition to the joints that everyone recognizes as joints, such as the legs and knees, there are many joints that are not noticeable because their movement is small, and each of the joints that make up the spine Vertebrae ( Tips ) There are joints between all of them.

There are very important tissues that connect the bones together to prevent these joints from slipping out of place and also control the movement of the joints. Ligaments ( Constitution ) And most joints are supported in various directions by multiple ligaments.

The severity of a sprain depends on the degree of damage to these ligaments. Ligaments stretch or tear depending on the magnitude and direction of the external force they receive. In the mildest cases, only a small portion of the fibers that make up the ligament are stretched or torn, but there are also more severe cases where multiple ligaments are completely torn. However, in these severe cases, the joint is always displaced when the ligament is torn, so strictly speaking, they cannot be called sprains, and are generally given a specific name for the injury, such as ligament damage.

In other words, a sprain is generally understood to be an injury in which the main pathology is ligament damage that does not result in tearing, and which does not involve a fracture.

How symptoms manifest

Symptoms of a sprain vary depending on the type of joint injured and the extent of the ligament damage. swelling ( Chief ) (Swelling), and Bleeding under the skin ( Exam ) The degree of swelling is proportional to the degree of ligament damage, i.e., the severity of the sprain. If there is significant swelling or subcutaneous bleeding (the skin turns purple), it may be that the ligament is torn, so do not self-diagnose, but be sure to get a diagnosis from a specialist.

If a torn ligament is left unrepaired, the joint will remain loose, which can lead to subsequent complications, so care must be taken.

Testing and diagnosis

A plain X-ray is always used to diagnose a sprain. This will confirm the presence or absence of a fracture or dislocation of the joint. In addition, X-rays may be taken under stress to check the degree of joint instability. However, since plain X-rays do not show the ligaments themselves, an MRI is required.

In recent years, MRI examinations have been used to assist in the diagnosis of many injuries and disorders, especially Knee joint ( Knee pain ) This is an essential test for ligament injuries.

Treatment methods

Sprains are generally treated conservatively (non-surgically).

Immediately after the injury, it is important to stop swelling and internal bleeding from becoming more severe. The measures to do this are as follows:

Local Rest

Icing

Compression

Affected limb ( guard ) of Highly Evaluated ( Public school ) (Elevation)

This is the basic principle (the initials are RICE).

Subsequent treatment will vary depending on the severity of the injury, but may include elastic bandages, Bandage ( Band-aid ) The basic approach is to control joint movement using taping, braces, etc.

There are cases where complete immobilization with a plaster cast is necessary, but some theories suggest that complete immobilization of a joint for a long period of time may actually inhibit the normal repair process of ligaments and have a negative effect on articular cartilage, so the indications for long-term plaster cast immobilization are limited. In any case, conservative treatment is the method of choice for sprains.

In addition, treatment for complete ligament tears, which are more serious than sprains, varies depending on various factors, such as the injured joint, the patient's age and occupation, and whether or not they participate in sports.

Athletes often require surgical treatment, such as repairing or reconstructing damaged ligaments.

Takeshi Takeda

Source: Houken “Sixth Edition Family Medicine Encyclopedia” Information about the Sixth Edition Family Medicine Encyclopedia

Japanese:

どんな外傷か

　関節が不自然な外力により生理的な可動範囲を超えるような動きを強制された時に発生する、代表的な外傷が捻挫や脱臼(だっきゅう)です。このうち関節を構成している相互の骨と骨の間にずれのないものを捻挫といい、多少なりともずれが生じたものを脱臼あるいは亜脱臼(あだっきゅう)といいます。

　捻挫を最も起こしやすい関節は足関節(そくかんせつ)ですが、人の体のなかには一般の人の想像をはるかに超える多数の関節があります。四肢の関節のなかにも肩、膝(ひざ)、足など、誰もが関節と認識する関節のほかに、動きが小さいために目立たない関節が多数ありますし、背骨を構成する一つひとつの椎骨(ついこつ)の間にもすべて関節があるのです。

　これらの関節がずれないように骨と骨の間をつなぎ止め、さらに関節の動きをコントロールする非常に重要な組織が靭帯(じんたい)です。そして、大半の関節は複数の靭帯でいろいろな方向から支えられているのです。

　捻挫の重傷度を左右するのは、これらの靭帯の損傷の程度です。靭帯は受けた外力の大きさや方向によって、伸びたり切れたりします。最も軽いのは靭帯を構成する線維のほんの一部が切れたり伸びたりするものですが、複数の靭帯が完全に断裂するような重いものもあります。ただし、このような重傷例は靭帯が断裂する際に必ず関節のずれを伴うので、厳密には捻挫とはいえず、○○靭帯損傷という具体的な外傷名がつけられるのが一般的です。

　すなわち、捻挫とは断裂にまでは至らない程度の靭帯損傷が主病態になった外傷で、しかも骨折は伴わないものと理解するのが一般的です。

症状の現れ方

　捻挫の症状は、受傷した関節の種類や靭帯損傷の程度によってさまざまです。一般的には関節の痛みや腫脹(しゅちょう)（はれ）、そして皮下出血(ひかしゅっけつ)の程度と、靭帯損傷の程度すなわち捻挫の重傷度とは比例します。はれや皮下出血（皮膚が紫色になる）が顕著な場合には靭帯が断裂しているおそれもあるので、自己診断はせず、必ず専門医の診断を受けるべきです。

　断裂した靭帯が修復されないまま経過すると、関節にゆるみが残り、それによる続発症が出ることもあるので注意が必要です。