Surgical treatment for complex adult lumbosacral lipomas excluding retethered cases: what are the benefits?

Objective: Although spinal dysraphism is a congenital anomaly, it is also diagnosed and treated in adults. The aim of this study was to analyze the clinical outcomes of adult patients with complex lumbosacral lipomatous malformations (LLMs).

Methods: Patients aged 19 years and older who were diagnosed with LLMs from January 2000 to December 2023 at a single institution were retrospectively reviewed. Clinical outcomes of pain and motor, sensory, and urological deficits were evaluated. Based on a uniform workup protocol, MRI, electromyography (EMG), nerve conduction study (NCS), and urodynamic study (UDS) findings were evaluated to assess the clinical correlation. Patients who had deteriorating symptoms with corresponding progressive abnormal findings underwent surgery.

Results: Thirty-three patients (median age 33 years) were included in this analysis; 22 patients were surgically treated and 11 patients were conservatively managed. The major surgical indications included intractable pain (n = 3), progressive motor deficits with ongoing activity on the EMG/NCS (n = 9), and urological symptoms with findings of neurogenic bladder on the UDS (n = 16). In the surgery group, 3 patients had intractable pain before surgery, with improvement after surgery in all patients. However, severe permanent neuropathic pain newly occurred in 4 of 22 patients (18%) who underwent surgery. Progression of motor weakness was stabilized by surgery in 7 of 9 patients (78%), and 2 patients showed minor motor deterioration after surgery. In addition, 1 patient without preoperative motor deficit developed new postoperative motor deficit. All patients with urological deficit had the most favorable outcomes, with improvement in 13 patients (81%) and stabilization in 3 patients (19%). For patients in the observation group who had mild and static deficits, the outcomes were favorable with no deterioration.

Conclusions: Surgical treatment for LLM in adult patients was most beneficial for those with neurogenic bladder. Surgery also had benefits for intractable pain and motor deficits, but caution is needed as unexpected neurological complications can occur.