Groin strain

Definition

Commonly termed groin strain, it refers to the tearing of the adductor muscles located at the groin in the inner side of the thighs.

Detailed anatomy of the muscle tissue depicting individual myofibrils or muscle fibres

Pathology

A strain of the groin occurs when pulling one or more adductor muscles. This group of muscles originates in the pelvic ring and attach along the inner side of the femur. They are the adductor brevis, adductor longus, adductor magnus gracilis, obturator externus, pectineus, which together form the hamstrings. These muscles are used when flexing and bending the hip joint when running and kicking. The damage can be minimal or result into a complete rupture of the muscle and avulsion. The pathology is graded as:

Grade 1: tear of few muscle fibres causing light pain and minimal functional impairment

Grade 2: damage to significant number of fibres resulting in moderate loss of function (most common)

Grade 3: complete rupture (avulsion) of a muscle and severe functional loss.

Classification

Fractures of the humerus shaft can display various patterns: transverse, oblique, spiral, and comminuted. In addition they are differentiated depending on whether the fracture is displaced or undisplaced, relative to the loss of bone alignment and closed or open fracture. The AO (Arbeitsgemeinschaft für Osteosynthesefragen) Foundation, an international organisation founded in Switzerland, focussing on research and education for the management of orthopaedic injuries), is one of most used systems available to characterise humerus shaft fractures. According to the AO humerus shaft fractures are divided into their level of comminution:

Type A - No comminution

Type B - Presence of butterfly fragment (wedge-shaped fragment of bone

Type C - Comminution

Anatomical illustration of a sprinter showing the strain of the inner thigh adductor muscles

Causes

A groin strain is a frequent pathology encountered in 10-30% of soccer and hockey players when the contraction of the adductor muscles (more frequently in the adductor longus) is so intense to cause a tear with external rotation of the abducted leg. Such tears occur with sudden muscle contraction while accelerating (springers) or as a muscle pull with intense stretching (long distance ball kick). A groin strain is frequent in sports such as:

Ice hockey

Soccer

Football

Running, sprinting

Long jumper athletes

Gymnastic

Skiing

Horse riding

In older age groin strains are more frequent as muscles loose flexibility

Risk factors

By being a typical sports injury the risk for a groin strain is enhanced with poor warm up without stretching prior to training. The pathology is more frequent in older athletes. Overuse and repetitive groin muscle activities can lead to adductor tendinopathy and eventually to muscle tears. The sports mentioned previously increase the risk of a groin tear. Additional risk factors are:

Lack of groin flexibility

Muscle weakness (groin, pelvis, core muscles)

Muscle strength discrepancy

Joint stiffness

Inadequate training technique

Incorrect posture during activity

Pain in the inner side of the thigh is a symptom of a groin strain

Symptom

The symptoms for a groin tear become evident at the time of injury and are particularly felt with activities of the adductor muscles. The typical symptoms include:

Sudden sharp pain to the groin area and inner thigh

Pain increasing with movement

Pain when squeezing the legs

Pain after cooling down

Muscle stiffness

Bruise

Inability to walk or play sport

Walking with a limp

Swelling

Muscle spasm

Muscle weakness

Clinical examination to test for groin tear

Diagnosis

The diagnosis of a groin tear is mostly obtained with clinical examination. Tenderness sensations at the site of a muscle tear and through the pubic area are clear signs of the pathology. In more severe tears, decreased muscle strength is observed while the examiner adducts the leg and the patient fails to resist the pressure. Due to the nature of this pathology, mostly MRI and ultrasound suffice to detect muscle tears in the region, swelling, haemorrhage and oedema.

An X-ray may be recommended in groin tears with suspected injury of the bony structures around the pelvis.

Treatment

Icing is beneficial to reduce inflammation after a groin tear

Nonoperative treatment

A groin tear is mostly treated conservatively beginning with a phase of rest followed by a rehabilitative regime. The prognosis varies from 3 weeks in mild tears to 6 weeks or longer in more severe cases. With muscle avulsion the prognosis may last for months. Additional conservative treatment includes:

Rest

Ice applications

Pain management with analgesics

Anti-inflammatory drugs (NSAIDs)

Local steroid injection

Reduced weight bearing if necessary

Surgery is only performed in case of a severe muscle rupture

Surgical treatment

Surgical treatment of a groin tear is rare and only performed in case of larger muscle ruptures and total muscle avulsion that includes the detachment of the bony area of muscle insertion. Open surgery is the method used and involves an incision over the area of tear to allow suturing the torn muscle or to reattach the tendon origin to the bone. Following surgery the patient may require the use of crutches for a few weeks. Occasionally symptoms may last for up to 6 months.

Massage of the affected muscles increases blood perfusion and muscle fibre mobility after injury

Rehabilitation

Physical therapy is indicated following a short period of rest. The rehabilitation program consists of gentle stretching and physical exercise of increasing strength. The therapist will also guide the patient to a planned return to sport including education in modifying those activities that may cause recidivism. A groin strain strapping can be applied immediately after injury to reduce swelling by compression as well as a preventative tool after recovery. Physiotherapy management includes:

Rest

Ice treatment

Local compression to reduce swelling

Anti-inflammatory therapy (NSAIDs)

Use of crutches

Stretching

Massage

Ultrasound

Electrotherapy

Activity modifying regime

Return to activity plan

A constriction bandage can reduce recidivism of groin tears

Prevention

Groin strains have a high rate of recidivism. Therefore it is critical to maintain the improved physical condition achieved with weeks of rehabilitation. The following rules will assist in preventing a groin tear:

Avoid premature return to sport

Gradual resume of sport by reducing activity time, and vigour (e.g. slower running speed)

Practicing movements posing stress to the adductor muscles

Including stretches and warm-ups for proper preparation to sport

Use groin straps, brace and groin shorts during activities.

Wear proper fitting shoes