A side strain is a

muscle strain A strain is an acute or chronic soft tissue injury that occurs to a muscle, tendon, or both. The equivalent injury to a ligament is a sprain. Generally, the muscle or tendon overstretches and partially tears, under more physical stress than i ...

caused by tearing of the

transversalis fascia The transversalis fascia (or transverse fascia) is a thin aponeurotic membrane of the abdomen. It lies between the inner surface of the transverse abdominal muscle and the parietal peritoneum. It forms part of the general layer of fascia lining ...

or the internal oblique muscle. When this occurs, stretching the muscle will be severely painful, making it difficult to move the arm, and the strain may later be marked by swelling or

bruising A bruise, also known as a contusion, is a type of hematoma of tissue, the most common cause being capillaries damaged by trauma, causing localized bleeding that extravasates into the surrounding interstitial tissues. Most bruises occur clos ...

. The strain usually occurs due to the internal oblique muscle contracting suddenly from a stretched position. It may happen suddenly, or over time from regular repetitive activity. It is common in

cricket Cricket is a bat-and-ball game played between two teams of eleven players on a field at the centre of which is a pitch with a wicket at each end, each comprising two bails balanced on three stumps. The batting side scores runs by striki ...

players, and occurs on the opposite side of the arm that is used for

bowling Bowling is a target sport and recreational activity in which a player rolls a ball toward pins (in pin bowling) or another target (in target bowling). The term ''bowling'' usually refers to pin bowling (most commonly ten-pin bowling), though ...

. The injury has also been reported in

rowing Rowing is the act of propelling a human-powered watercraft using the sweeping motions of oars to displace water and generate reactional propulsion. Rowing is functionally similar to paddling, but rowing requires oars to be mechanically atta ...

baseball Baseball is a bat-and-ball sport played between two teams of nine players each, taking turns batting and fielding. The game occurs over the course of several plays, with each play generally beginning when a player on the fielding tea ...

and

ice hockey Ice hockey (or simply hockey) is a team sport played on ice skates, usually on an ice skating rink with lines and markings specific to the sport. It belongs to a family of sports called hockey. In ice hockey, two opposing teams use ice hock ...

and pool. The preferred treatment for a side strain is regular rest and inactivity on the affected muscle. With appropriate rest, regular activity on the muscle can occur between 4 and 6 weeks, though it may take longer.

References

Injuries of abdomen, lower back, lumbar spine and pelvis {{injury-stub