A sprain is an injury to one or more ligaments without any joint displacement (dislocation). The injury can range from straightforward over-stretching (mild sprain) to total rupture (severe sprain) via tearing of a few fibre bundles (moderate sprain). Ligaments join two bones together to form a joint. They are composed of several fibre bundles and are not very stretchy. Following a trauma (impact, contrary movement), the joint can be forced into a position that goes beyond its natural range of motion, leading to a painful injury. A mild sprain is also called a "strain" or a "twist".
A thumb sprain is an injury to the ligament of the metacarpophalangeal joint of the thumb: the ulnar collateral ligament (= medial collatera). When taking part in certain sports (handball, volley-ball, skiing or surfing), this injury can occur following an impact causing the thumb to move towards the outside of the hand. The thumb's position is forced beyond the natural maximum gap between the thumb and the hand, the ligament is stretched and the thumb is sprained. This sprain is also known as "skier's thumb".
Beware since a thumb sprain may sometimes be accompanied by a fracture at the base of the 1st phalanx.
The aim of an orthopaedic solution is to relieve pain (analgesia) and heal the ligament. Depending on the severity of the sprain, it ranges from strapping to immobilising braces: made-to-measure heat-moulded braces and standard wrist-thumb or thumb braces or splints. The thumb is held in a position close to its functional position, enabling almost normal use of the injured hand to be maintained.
It is important to accept that the thumb will be immobilised for a certain period. However, the main risk of treatment is chronic instability, leading to loss of "thumb-finger" pincer grasp efficiency.
Tél : 04 77 91 30 30 - Fax : 04 77 79 62 66
73, rue de la Tour BP 78 - 42002 Saint Etienne Cedex 1 France