Purpose: More interest in the treatment of rectus diastasis has been evoked lately. Following the postpartum females from a great distance, the middle-aged males living with obesity are the second most common group of rectus diastasis patients. Although gender differences are considered frequently in regard to cosmetic appearance and symptoms, it is less obvious in classifications and subsequent treatment strategies. Is a unisex approach of rectus diastasis still applicable? The lack of a firm answer warrants this review of the current literature.

Methods: An explorative free-text multi-database bibliographic search (Pubmed/CENTRAL/EMBASE/PEDro/Scholar) was performed with the focus on the rectus diastasis in males. Anticipating the limited references, the design was a non-systematic review. All studies, regardless of study type, language or time period, describing etiology, symptoms, classification and/or treatment options were eligible for inclusion. From the articles retrieved out of this search, additional references were identified by a manual search among the cited references.

Results: The multi-database search resulted in a total of 7633 records. Based on the title and abstract 95 records were full text assessed for eligibility. Eleven studies were identified as relevant, six by cross-reference and another four by hand-search were added to provide an insight in gender-specific aspects in rectus diastase. Hereditary causes are differences in collagen-like composition of types and concomitant abdominal aneurysm as well as gender differences in the linea alba architecture. Acquired etiology is distributed into both absolute pressure by visceral obesity and relative pressure caused by weight lifting or improper exercises. Furthermore, the impact of muscle thickness and age are considered as influencers of biomechanics. Gender differences can also play a role in symptoms of body image and core stability. It is known that there are anatomical differences between male and female persons; more transverse fibers are found in infra-umbilical region in women. In classifications the awareness of male rectus diastasis is limited, treatment outcome studies are scarce on males.

Conclusion: An overview of male-specific aspects of rectus diastasis is provided, underlining that key aspects surrounding rectus diastasis in males differ from females. Although males are the minority of rectus diastasis patients, we recommend that the male rectus diastasis as a concept should be specifically acknowledged in classifications systems and study outcome reporting to evaluate this subgroup more accurately in the future.