Sprains and strains

About sprains and strains

Soft tissue injuries may be sudden (acute) or long-standing (chronic).

Soft tissues include ligaments, muscles and tendons.

A sprain is an injury to the ligaments and capsule of a joint in the body.

A strain is an injury to muscles or tendons.

Healing depends on various factors including the type of tissue and severity of injury, treatment undertaken, previous injuries, and the age and general health of the person.

Causes of sprains and strains

Soft tissue structures are made from bundles of fibres. Muscles and tendons contain specialised cells that monitor the degree of contraction and stretch.

With general use, muscles gently contract to resist overstretching. However, sudden twists or jolts can apply greater force than the tissue can tolerate, resulting in a tear or rupture of the fibres. The damage to these fibres triggers an immune reaction called inflammation.

Inflammation is a complex cascade of biological processes that results in the classic swelling, redness and tenderness associated with sprains and strains. In higher-grade injuries, bleeding from broken blood vessels increases the degree of swelling.

Injuries to soft tissues such as ligaments, muscles and tendons can come on suddenly, and occasionally be recurrent or get worse over time (usually due to suboptimal treatment and rehabilitation).

A sudden injury is often related to a specific incident and is termed an acute soft tissue injury. Acute usually means the injury has occurred within the previous 72 hours.

An injury that has been present for at least 3 months is often referred to as a chronic soft tissue injury.

Sprains

Joints are stabilised by a joint capsule and supported by tough bands of connective tissue called ligaments. These structures are often called passive or non-contractile supports.

The entire joint is enclosed inside a membrane filled with lubricating synovial fluid, which helps to nourish the joint and provide extra cushioning against impact.

A sprain is an injury that involves tearing of the ligaments or joint capsule or both.

Common sites for sprains include the thumb, ankle and knee.

Strains

Muscles traverse across joints and are anchored to bones via tendons. Muscles can cross either one joint (single-joint muscles) or 2 or more joints (multi-joint muscles).

Muscles contract (or shorten) and pull on their tendon insertion into the bone and thus produce movement of a joint. Multi-joint muscles (like the hamstrings, quadriceps and our main calf muscle called the gastrocnemius) are injured at much higher rates than single joint muscles.

Injury to these tendons or the muscles themselves is called a strain.

Common sites for strains include the calf, groin and hamstring.

Symptoms of sprains and strains

The symptoms of a sprain or strain may include:

• pain
• swelling
• stiffness
• reduced function.

Degrees of severity of a sprain or strain

Acute soft tissue injuries can be graded according to their severity. The classic grading system for ligaments is from grade I to grade III:

Grade I – Injury to some ligament fibres

Signs and symptoms

• minimal function limitation
• normal range of motion
• minimal swelling
• localised pain with palpation (pressing).

Grade II – Injury to a considerable portion of the ligament fibres

Signs and symptoms

• significant pain with palpation
• considerable swelling
• moderate functional limitation.

Grade III – Complete rupture of ligament

Signs and symptoms

• audible ‘pop’ may have been heard at time of injury
• occasionally delayed onset of pain (as there is complete disruption of ligament, there can be limited pain before inflammatory process starts)
• considerable swelling and bleeding
• significant functional limitation.

Grading of muscle injuries classically follows this same formula of grade I to grade III. However, there are new grading systems that expand upon this for further depth and nuance:

Grade 0a – Focal muscle injury with normal MRI

Signs and symptoms

• ‘awareness’ of muscle with use
• localised tenderness with palpation.

Grade 0b – Generalised muscle soreness with normal MRI

Signs and symptoms

• no trauma or moment in time
• muscle pain usually starts 24 to 48 hours after an unaccustomed bout of exercise
• widespread tenderness with palpation.

Grade 1 – Small local tears to muscle

Signs and symptoms

• noticeable moment in time
• immediate onset of pain
• localised tenderness with palpation
• no loss of range of motion
• limited loss muscle power.

Grade 2 – Moderate localised tears to muscle

Signs and symptoms

• noticeable moment in time
• immediate onset of pain
• localised tenderness with palpation
• no loss of range of motion
• moderate loss of muscle power
• moderate functional limitation.

Grade 3 – Extensive tears to muscle

Signs and symptoms

• noticeable moment in time
• immediate onset of pain
• localised tenderness with palpation
• can have some loss of range of motion
• significant loss of muscle power
• significant functional limitation.

Grade 4 – Complete tears to muscle belly or tendon, or between junction of muscle and tendon

Signs and symptoms

• noticeable moment in time
• immediate onset of pain
• localised tenderness with palpation
• can have visible deformity to muscle
• can have some loss of range of motion
• significant loss of muscle power
• significant functional limitation.

First aid for sprains or strains

Suggestions for immediate treatment of acute sprains or strains include:

• Stop your activity.
• Rest the injured area.
• Put icepacks on the area for 20 minutes every 2 waking hours, separated from the skin by wet towelling.
• Compress or bandage the injured site firmly, extending the wrapping from below to above.
• Elevate (raise) the injured area above heart height whenever practical.
• Avoid heat, alcohol, running and direct, firm massage of the affected area in the first 72 hours after the injury, as this can increase swelling.
• If symptoms get worse in the first 24 hours, see your doctor for further medical investigation.

Treatment for sprains and strains

Most soft tissue injuries take a few weeks to heal, depending on the severity of the sprain or strain, any subsequent injuries or issues such as weakness, stiffness, poor balance or function, and the general health of the person.

Hamstring strains (the most common strain) have an average return to play time of 3 weeks.

Lateral ankle sprains (one of the most common ligament sprains) have an average return to play time of 2.5 weeks. However, the variation can be large with some studies citing return to play times of over 100 days for some hamstring strains and ankle sprains.

It’s important to get the correct treatment as soon after the injury as possible to help faster recovery. See your doctor or physiotherapist if you don’t have full function of the area, or if the pain and swelling don't subside after a couple of days.

Treatment may include:

• exercises – under the guidance of your doctor or other health professional, to promote healing, strength and flexibility
• bracing and external supports – to help protect the injured area and allow greater participation in normal daily activities whilst the injury heals
• manual techniques – such as mobilisation and massage
• electrotherapy
• pain-relieving medication – talk to your doctor or pharmacist before taking any medications, as they can sometimes disrupt the healing of soft tissue injuries
• gradually introducing activities to back-to-normal levels.

Severe injuries, where the tissue has completely ruptured, may need surgery to put the torn pieces back together. Surgically repaired grade III injuries will require significant treatment to regain strength and function.

Whether you have surgery or a period of immobilisation and physical therapy as the treatment for a grade III injury, medium to long-term functional outcomes is similar for either treatment.

Where to get help

• Your GP (doctor)
• Physiotherapist

Need treatment today?

Need treatment today, but it's not life-threatening and you can't get a GP appointment, there are services available:

• Urgent Care Clinics – provide care for conditions that require treatment today but not an emergency response (extended hours)
• Nurse-on-Call Tel. 1300 60 60 24 – for expert health information and advice (24 hours, 7 days)

Emergency care

• In an emergency, always call triple zero (000)
• Emergency department of your nearest hospital

More information

• Australian Physiotherapy Association Tel. (03) 9092 0888