Variants of Core Muscle Injuries
Core muscle injuries includes a number of variants. Each variant has a slightly different mechanism of injury; therefore, this accounts for the difference in symptoms. The injury can involve any number of muscles and there could be 121 different combinations of surgeries.
• Rectus Abdominis/Adductor Variant This is the most common for the syndrome of chronic, severe, exertional, and lateral rectus abdominis pain related to the latter muscle's insertion onto the pubis. Classically, a tear or an attenuation of the rectus abdominis insertion causes the syndrome as well as possible secondary pain near the adductor insertion sites onto the pubis.
• Adductor Longus Variant Adductor longus pain is a principal component of the pain. In some cases, the adductor longus pain occurs without ay rectus abdominis pain.
• Snapping Hip Syndrome An elicitation of a "hip snap" on physical examination or with a similar maneuver. This variant most often occurs in runners and in women.
• Pectineus Variant Adductor pectineus pain is the principal component of the pain.
• Spigelian Variant There is pronounced pain in the spigelian area, the same site where hernias can occur. In this case, the pain is not due to a hernia, but to a vertical extension of the same musculofascial shredding that characterizes the more classic rectus abdominis variant.
• Baseball Pitcher / Hockey Goalie Syndrome This syndrome tends to occur in the aforementioned athletes and primarily involves a muscular hernia through the fascia or epimysium investing the belly of the adductor longus muscle.
• Osteitis Pubis Variant In many cases, there is some degree of osteitis pubis. Most of the time, the osteitis pubis pain will resolve with appropriate treatment of Athletic Pubalgia. However, in some cases, the osteitis pubis pain is so diffuse and painful that the pain takes longer to (and sometimes does not) resolve. One must also be aware of the possibility of primary osteitis pubis.
• Iliopsoas Variant The pain is principally near the psoas insertion site onto the lesser trochanter. The pain results from a psoas bursitis that is secondary to the instability caused by the weak rectus abdominis attachment.
• Gracilis Variant The gracilis is more involved than the adductor longus and the pain resulting from a compartment syndrome due to relatively unopposed action of the adductors with respect to the pubic joint.
• Athlete's Rib Syndrome This tends to involve rowers, tennis players and boxers. The rectus abdominis fibers that interdigitate with the lower most intercostals muscles sublux the 11th and 12th ribs and/or cartilages.
• Superior Rectus Variant This syndrome is an intermediate between the Spigelian and the Athlete's Rib Variant.
• Sartorius Variant This tends to occur in women. There is considerable pain at the sartorius insertion site in addition to lower rectus abdominis pain.
• Labral Tear/Snapping Hip Variant The symptoms and finding of these two variants can be very similar and often the problems coexist.
• Round Ligament Syndrome Distinguishing Athletic Pubalgia from endometriosis can be difficult and there seems to be a definite syndrome in athletes involving exertion and pain related to the round ligament itself.
• Adductor Avulsion Variant The adductor longus can partially or completely avulse from the pubis resulting in considerable pain.
• Adductor Calcification Syndromes These syndromes are often seen in Bull Riders. Often, years after the injury, the calcification that results from this trauma causes severe inflammation and pain.
• Iliotibilal Tract Syndromes Pain in this area can be secondary to compensation from a primary rectus abdominis problem.
• Rectus Femoris, Quadratus or Pectineus Syndromes Pain can occur either primarily or secondarily along other insertion sites or bursae related to these muscles and tendons.