Symphysiotomy for Pelvic Access in Difficult Extirpative Surgery

Abstract

Adequate access can be a significant problem when performing procedures deep within the pelvis. This can be difficult particularly in small men. We were faced with the challenge of removing a large benign presacral tumour in a 60 kg man with small pelvic dimensions. We used a technique that involved splitting the fibrocartilagenous symphysis pubis and distracting the joint to increase the exposure. This technique has been reported infrequently for similar surgery. CASE HISTORYA 37-year-old Chinese-born man presented to his local doctor with a 6-month history of left iliac fossa pain, and increasing constipation and urinary frequency. He had previously been well with no significant family history. Abdominal examination demonstrated no mass but on rectal examination a large smooth extra-rectal mass was felt pushing the rectum forward. Computed tomography (CT) was performed ( Fig. 1). Subsequently, a CT-guided biopsy via the greater sciatic notch confirmed the diagnosis of benign nerve sheath tumour. He was then referred to the senior author (MJD) for ongoing management. A magnetic resonance image (MRI) was obtained to show the relationship to the sacrum (see Fig. 2). SURGICAL TECHNIQUEThe patient was positioned in lithotomy position. A midline lower abdominal incision was made and a laparotomy was performed. The rectum was mobilized in the mesorectal plane as low down in the pelvis as possible. Both ureters were identified above the mass and protected during the dissection. The hypogastric nerves were preserved on both sides, as were the obturator nerves. The upper pole of the tumour was dissected on the remaining three sides but the inferior 2/3 could not be adequately accessed.The lower end of the incision was extended laterally on both sides. The crests of the pubic bones and symphysis pubis were then displayed and the insertion of the rectus sheath and muscle divided to assist exposure. A periosteal elevator was used to clear the anterior and superior surface of the pubic bones and joint. An AO Set (Synthes, Switzerland) four and five hole plate were fitted separately to the anterior and superior surface of the pubic bones across the symphysis pubis, which was done at this stage to allow accurate reduction at the end of the procedure. The plates were then removed and the joint split with a scalpel blade. The inferior pubic ligament was divided and the joint was then slowly distracted with a paediatric rib retractor until a 5-6 cm gap was achieved. Access to the pelvis was markedly improved with no obvious damage other than a tearing of a small dorsal vein of the penis.The tumour was then able to be removed by a combination of sharp and blunt dissection. It seemed to arise from the left side of the sacral plexus and was removed with 1120 mL total blood loss. The retrorectal space was drained with an Exu-drain (Astra, Sydney, Australia). The AO (Synthes) plates were then reapplied with assistant-derived pressure from both sides to accomplish the reduction (Fig. 3). The rectus sheath insertion was repaired and the...