From intermediate hockey players, to NHL'ers, the groin muscle strain is one of the most common injuries sustained in hockey. The groin muscle is recruited during the complex movement pattern of the skating stride. This stride is required to produce explosive movements to allow the skater to keep up with the ever-changing direction of the puck. The instantaneous need to accelerate, decelerate and change directions when playing hockey, applies a great deal of strain on the groin muscle and puts it at risk of injury. If factors affecting the recruitment of the groin muscle during the skating stride are not optimal, injury occurs.

Anatomy

The groin muscle actually refers to the adductor muscle group as well as the hip flexor muscle - iliopsoas. The adductor muscle group consists of 3 closely knit muscles, which originate from the inner pelvis, where the two pelvic bones join one another, and insert on to the inner aspect of the upper leg bone (femur). The hip flexor muscle attaches from the lower spine and pelvis, and inserts onto the head of the femur. A groin strain may involve either or both muscle groups.

Signs and Symptoms of Injury

• Tenderness on palpation of the affected muscle, usually close to its origin
• Reproduction of pain with elongation of the affected muscle
• Reproduction of pain with a contraction of the affected muscle
• Possible bruising and swelling

Accessory Factors Which May Contribute to Injury

In my clinical experience, rarely is a groin strain simply the result of excessive load applied to the muscle tissue. Often there exist contributing factors predisposing the player to injury such as: mechanical dysfunction of the hip and/or pelvis, and lack of adequate core stability. Mechanical dysfunction refers to joint mobility restrictions. As stated earlier, the groin muscles insert into the pelvis and the pelvis articulates with the tailbone (sacrum). This joint is called the Sacro-iliac joint, commonly referred to as the SI joint. If movement restriction exists at the SI joint, then the system as a whole is not operating in the fashion of which it is designed to absorb strain. The result being, normal stresses, such as skating, may not adequately be absorbed and injury occurs at the weakest point of the system. This may result in a groin strain or injuries somewhere else in the system, i.e. the SI joint itself. The same is true for the hip joint. Failure of normal hip mobility may predispose the groin muscle to be subjected to altered strain and result in injury. Joint mobility may be restricted for different reasons such as the effects of: habitual postures, poor ergonomics, muscle imbalances, and/or lack of appropriate treatment of previous injuries to the joint.

Core stability is also an important concept, which if lacking, predisposes the athlete to a multitude of various injuries. Unfortunately, core stability has become a "buzz" marketing word, and is commonly taught incorrectly by personal trainers and even some physiotherapists. Core stability refers to the deep muscle groups of the lumbar spine, which if properly recruited, creates stability of the "core". On numerous occasions, patients have shown me exercises that they have been taught by various professionals to work on their "core" muscles. Usually these exercises involve strengthening the rectus abdominus and internal/external oblique muscles, commonly referred to as your "six pack" muscles, which are not your "core stability" muscles. Physiotherapist Angus Driver has written a previous Ereport on this concept and I encourage you to review this article, written in May, 2003, at www.semisportmed.com. Weakness, or recruitment failure, of your core stability muscles results in failure of the core to become a stable base for the limbs to exert forces from. With the hockey stride being such an explosive, force-producing maneuver, stability of the core is extremely important. Again, if the core is not stable, the normal stresses exerted on the system produce strain in a manner the system is not designed to absorb. The result, the weakest part of the system fails and injury occurs. If the groin is the weakest part of the system, it doesn't mean the muscle group is literally weak, but rather the weakness of the muscles ability to absorb the normal strain which is abnormally applied to it.

Treatment

The treatment of a groin strain is successful only if all of the factors resulting in the injury are identified and addressed. If not, the injury can linger for a prolonged period of time. Therefore treatment may consist of the following:

• R.I.C.E (Rest, ice, compression, elevation - in the initial acute stages)
• Stretching and strengthening exercises of the groin muscles
• Core Stability training
• SI and hip joint mobilization/manipulation
• Theurapeutic massage
• Gradual return to sport
• Skating technique correction

If joint mechanics and core stability is not fully restored, the injury to the groin muscles may heal, but re-injury is common. More and more elite and professional athletes participate in core stability training as preventative measures. The stronger your "core", the greater is your ability to exert forces from it and allow you to excel in athletic performance at the highest level. In addition, a stable core maximizes the athletes potential to avoid injury.

References:

1. Brukner, Peter. Khan, Karim. Clinical Sports Medicine 2^nd ed. 2001: The McGraw-Hill Companies Inc.