Updated: Nov 19, 2020
Hockey and soccer are two sports whose athletes commonly suffer groin strains, but groin injuries are certainly not limited to just these sports (cross country skiing, fencing, hand ball, track & field and others). Both these sports require frequent and strong contraction (eccentric contraction) of the muscles along the inside of thigh (the adductors). (1)
Statistically, groin strains account for about 10% of all injuries in the NHL. Surprisingly the majority of these injuries do not involve a direct hit or contact. The majority of these strains occur during pre-season and not as much during the regular reason. (2) This has lead researchers to correlate the strength of the muscles along the inside of the thigh (adductor muscles) to in incidence of groin injuries (Adductor Strains). (3)
WHAT IS A GROIN STRAIN?
A groin strain is an injury to the muscles of the inner hip and thigh (adductor muscles). These muscles fan out from the pelvis all the way to the inner part of the upper leg. The adductor longus is the most commonly injured muscle in the adductor group. (4)
The primary action of the adductor muscles is to pull the leg inwards (adduction) and also to help bend and rotate the leg at the hip joint. A strain occurs when one or more of the groin muscles is either stretched too far, or is forcefully contracted while it is being stretched, resulting in torn muscle fibres.
SYMPTOMS OF A GROIN STRAIN
Common symptoms of a groin strain are pain when walking, sitting, or bending at the hip. This pain is often described as being achy, burning, and in some cases electric in nature (especially when nerve irritation is part of the injury).
Groin strains are usually graded based on how many muscle fibres have been torn, and on how many activities have been limited due to the injury. (5)
Grade I Strain: A few muscle fibres are torn, pain is mild and activities are minimally affected.
Grade II Strain: A moderate number of muscle fibres are torn, pain is moderate, and activities can be limited. There may be moderate bruising and/or swelling.
Grade III Strain: A large number of muscle fibres are torn, or in rare cases, there is a complete tear, pain is severe, and activity is very limited. There may be significant bruising and/or swelling.
UNDERSTANDING SKATING BIOMECHANICS
In order to understand why hockey players are at risk of sustaining a groin injury, we need to first examine the basic skating stride and the muscles that are involved in performing this complex movement. A basic skating stride can be divided into two phases:
Support Phase is when a skater pushes off with one leg and glides.
During skating the groin muscles act to counterbalance the forces that are required to push a skater forward. These are generated at the hip, knee and ankle. When a skater pushes off from side-to-side during the Support Phase, the hip moves back (extension) and outwards (abduction), the knee straightens (extension), and the ankle bends downwards (plantar flexion) resulting in forward motion.
Swing Phase is when the leg is brought back to center in order to push-off again. (6; 7)
In response to these actions, the groin muscles lengthen under tension (eccentrically contract) in order to maintain balance, absorb shock, and harness the kinetic energy used to flex the hip and pull the leg inwards (adduction) during the Swing Phase. This ensures that the push-off leg is brought back to center efficiently, and this sets up the next push-off with the opposite leg, allowing for a smooth transition between movements and good continuity of motion. (6; 7; 8)
WHY ARE HOCKEY PLAYERS AT RISK?
In hockey players, the gluteal muscles are often stronger than the groin muscles, and often tend to overpower them. This muscle imbalance can lead to injury because strong eccentric contractions by the adductors are required to counterbalance the outward leg motion during skating, and when the groin muscles are weak in comparison to the gluteal muscles, they are often overloaded, and then pulled, resulting in a muscle tear. (3; 9)
HOW WE TREAT GROIN INJURIES AT KINETIC HEALTH
Groin injuries can be very painful, especially during the Acute Stage. Our treatment methods vary based on the phase of groin injury. It is important to work with your practitioner through all three phases for a full recovery. We divide our treatment strategy into three key phases:
Sports Specific Training
Treatment in Acute Phase of a Groin Injury
Even during the Acute Phase it is important to address the groin injury as soon as possible, so the injured person can speedily return to activity. The following are some of the key components of our treatment protocol and the exercises we recommend during the Acute Stage of a groin injury:
RICE (rest, ice, compression, and elevation). Read Dr. Abelson’s blog “Ice or Heat – Which Should I Use”.
Gentle manual therapy as tolerated.
Passive hip range-of-motion exercises, within a pain-free range only.
Bent knee isometric strengthening (sub-maximal effort; do not use straight legs in order to avoid re-injury of the adductor muscles).
Progressive resistance exercises (not weight-bearing, and in a pain-free range).
Flexibility exercise of muscles that are not involved in the injury.
Strengthening of the muscles in the lower extremity on the opposite side of the body’s injury (contra-lateral side).
Treatment in the Sub-acute Phase of a Groin Injury
Progression to the Sub-acute Phase of treatment can proceed only after the patient is able to contract the adductor muscles against gravity, without experiencing pain. The following are some of the key components of our treatment protocol and exercises we recommend during the Sub-acute Stages of a groin injury:
Continue with manual therapy, but now address a larger kinetic chain of involved structures. The "MSR - Adductor Abdominal Connection" procedure would be a good example.
Cycling and swimming is allowed; cycling is an excellent warmup.
Flexibility program that focuses on more than just the adductors. "Sam's Daily Five Stretches" would be a great example.
Balancing on one leg.
Progressive resistance exercises (concentric adduction, within a pain-free range-of-motion). We recommend the use of standing adduction exercises that use a Theraband. Research has shown that eccentric training can be effective and useful in the rehabilitation of groin injuries.
Forward lunges in combination with reciprocal arm movements.
Pelvic tilt exercises.
Wobble board squats within a pain-free range-of-motion.
Sports Specific Training for Groin Injuries
During this phase of recovery and treatment, the objective is to increase adduction strength on the injured side to at least 90 to 100 percent of abduction strength on the non-injured side. To do this:
Take the time to warm up. This can help to avoid the often high incidence of groin re-injuries.
Standing resistance training that mimics the activity (for example: mimicking the skating stride or kneeling on ice and performing adductor pull-togethers).
Use of slider boards in multi-planar vectors
Bent-knee to straight-leg ball squeezes.
When one considers the high rate of recurrent groin strains (9), the need for a structured rehabilitation program becomes of the utmost importance. The probability of having a reoccurring groin injury (when the initial injury is NOT rehabilitated properly) increases by two to three times. (10) This research comes from the British Journal of Medicine (BJM), where the BJM conducted research on soccer players, who experience similar problems and biomechanical stress as those experienced by hockey players.
Injured tissue needs the time to repair, weak muscles need to strengthen. Once the injury has healed, a carefully designed program of dynamic stretching, strengthening, and core stability training can go a long way in preventing future injuries. Bottom line, if you are suffering from a groin strain (no matter what the cause), you need to get the care you require, delivered in a logical, systematic fashion.
Take the time to speak to one of our experienced practitioners at Kinetic Health, and build a customized treatment and exercise program. This program will systematically and effectively move you through the phases of injury recovery, and reduce the chances of re-injury. We can help you stay active and pain free.
Make an appointment with our incredible team at Kinetic Health in NW Calgary. Just scan the QR code with your phones camera and click the link, or call Kinetic Health at 403-241-3772 to make an appointment today!
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