Commonly termed groin strain, it refers to the tearing of the adductor muscles located at the groin in the inner side of the thighs.
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.
There are various classification systems for a shoulder impingement syndrome.
Stages of subacromial impingement in athletes - Jobe’s Classification
Pure impingement with no instability
Primary instability, with capsular and labral injury with secondary impingement, which can be internal or subacromial impingement
Primary instability due to intrinsic ligament laxity with secondary impingement
Pure instability with no impingement.
Grading of impingement changes - Milgrom’s Ultrasound Classification:
Stage 1 Bursal thickness from 1.5 to 2.0 mm
Stage 2 Bursal thickness over 2.0 mm
Stage 3 Partial or full thickness tear of the rotator cuff.
Impingement lesions - Copeland Levy Classification:
This is based on the location of the impingement, either on the acromial or the bursal side.
A0 normal - smooth surface
A1 minor deterioration, haemorrhage or local inflammation
A2 marked scuffing/damage of the undersurface of the acromion and coraco-acromial ligament
A3 exposed bone areas.
B0 normal - smooth surface
B1 minor deterioration, haemorrhage, inflammation
B2 major deterioration of the cuff, partial thickness tear
B3 full thickness tear of the rotator cuff
B4 massive cuff tear.
According to the Habermeyer Classification the fractures to the proximal humerus are divided into:
Type 0 one fractured part without dislocation
Type A two-part fracture of the great tuberosity and lesser tuberosity avulsion
Type B involves the humerus “surgical” neck below the femoral head as two-part, three-part and four-part with one or both tuberosities
Type C involves the humerus anatomical neck (between the head and greater tuberosity) as two-part, three-part and four-part with one or both the greater and lesser tuberosities.
These are defined further as:
One-part fractures are non-displaced fractures or fractures with minimal displacement
Two-part fractures only involve a single segment
Three-part fractures involve two segments
Four-part fractures occur when all humeral segments are involved (see image in pathology section)
The injury severity is proportional to the increasing number of fractures.
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:
Long jumper athletes
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
Inadequate training technique
Incorrect posture during activity
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
Inability to walk or play sport
Walking with a limp
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.
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:
Pain management with analgesics
Anti-inflammatory drugs (NSAIDs)
Local steroid injection
Reduced weight bearing if necessary
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.
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:
Local compression to reduce swelling
Anti-inflammatory therapy (NSAIDs)
Use of crutches
Activity modifying regime
Return to activity plan
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