Beyond cloacal malformation. Addressing unclassifiable complexity

Cloacal malformations are a spectrum of complex congenital anomalies traditionally classified by common channel length, urethral length, Müllerian configuration, and sacral or spinal abnormalities. Classification guides reconstructive strategy and informs prognosis. However, a subset of patients present with atypical anatomy that defies standard classification systems, complicating surgical planning and prediction of outcomes.

Our cloacal malformation multidisciplinary service utilises a pathway based on common channel length, Mullerian anomalies, urethral length and sacral spinal abnormalities. We aimed to assess the management and faecal continence outcomes of these unclassifiable cases.

We conducted a retrospective review of 82 patients referred for primary reconstruction from 2010, analysing categorical and numerical data using Fisher's exact and Mann-Whitney U tests. Patients were categorised as classic cloaca, posterior cloaca, and unclassifiable (exhibited complex/atypical anatomy such as indistinct of absent common channels, duplication of urogenital structures or associated covered cloacal exstrophy variants).

Of 82 patients, 15 were unclassifiable. The latter group had more co-morbidities: 75 % (n = 6) with spinal anomalies requiring neurosurgery, and 93 % (n = 14) with renal anomalies. They were more likely to undergo laparotomy (n = 10) and had poorer faecal continence outcomes, with bowel function score of 6, compared to 13 in the classic cloaca group. Surgical management was more complex, with all patients requiring functional diversion procedures rather than standard anatomical reconstruction, representing a form of "non-anatomical reconstruction".

Unclassified cloacal malformation group represent a significant challenge, with poorer functional outcomes likely due to greater anatomical complexity and coexisting anomalies. Successful management requires experience in cloacal reconstruction and operative planning tailored to each patient's unique anatomy.