SAFETY AND EFFICACY OF INFLATABLE PENILE PROSTHESES IN PEOPLE WITH SPINAL CORD INJURY/DYSFUNCTION: A HOLISTIC TERTIARY REFERRAL CENTER WORKFLOW

1. Introduction ED is common after SCI/D and often coexists with NLUTD, NBD, spasticity, AD risk and high vulnerability to pressure injuries. PP implantation in SCI/D has historically been regarded as “high risk,” mainly because of increased infection, erosion/extrusion, revision and explant rates reported in older series. This study approaches IPP surgery in SCI/D as a workflow-dependent intervention, where outcomes are influenced by all steps in a Spinal Unit: pre-operative optimization, surgical technique and post-operative management. 2. Aim of the study The primary objective of the study was to assess the safety of contemporary IPP implantation in selected men with SCI/D managed within a structured multidisciplinary workflow by a tertiary referral Spinal Unit. Secondary objectives included: to assess functional efficacy of IPPs; to quantify patient satisfaction and likelihood of recommending the procedure; to evaluate impact on bladder and bowel management, and IC; to evaluate referral appropriateness in a large screened cohort and develop a referral appropriateness PP score (SCI/D-RAPPS) to use in routine clinical practice; to collect and summarize all the precautions adopted in a practical risk mitigation plan for other surgeons who are approaching IPP surgery in SCI/D. 3. Materials and methods After the approval by the Institutional Review Board, a prospective, longitudinal, single-center study was initiated in an Italian tertiary referral Spinal Unit setting. The initial enrollment period was from Feb 2023 to Jan 2024 with a 12-month-long follow-up period ending in Jan 2025. Due to reduced enrollment for strict selection process, the study was extended with a new enrollment period from Jun 2024 to May 2025, with follow-up period prolonged up to May 2026. Two linked samples were analyzed: (1) a consecutive cohort of 263 men with SCI/D evaluated for IPP during the enrollment period by our center, considered to develop the SCI/D-RAPPS; (2) the subgroup that underwent three-piece IPP implantation (n = 12) with standardized pre, peri and post-operative data collection within a follow-up of 12 months. To reduce the risk of complications, all factors that may influence surgical outcomes were evaluated and optimized in people addressed to IPP surgery, including bladder and bowel management, IC technique, spasticity management, skin integrity and UTI risk. In the first cohort, multivariate logistic regression with internal bootstrap was used to develop a model to predict appropriateness for IPP evaluation according to different patient characteristics. In the second sample, PROMs were collected for bladder evaluation (e.g., SF-Qualiveen, ICIQ-UI SF, ease of IC insertion), bowel function (e.g., NBD score, MENTOR tool) and patient experience (QoLSPP and 10-point Likert scales for evaluating satisfaction and recommendation). 4. Results Among 263 evaluated men with SCI/D, 61/263 (23.2%) referrals were classified as appropriate and 202/263 (76.8%) as inappropriate. In multivariate analysis, referral appropriateness was associated with younger age (OR 0.97 per year), lower comorbidity burden (CCI ≥ 3: OR 0.26), lower UTI burden (OR 0.26), stable partner status (OR 2.52) and an appropriate psychological profile (OR 10.71). Model performance showed Nagelkerke’s R² = 0.298, apparent AUC = 0.801 and corrected AUC = 0.751 after bootstrap validation (B = 1, 000). Using p ≥ 0.30, sensitivity and specificity were 0.705 and 0.738, respectively. A SCI/D-RAPPS software application probability calculator was developed to use this score in routine clinical practice. Twelve out of 61 (19.7%) patients underwent three-piece IPP implantation, while the others refused after adequate counselling and/or presented clinical issues to solve before IPP. The median admission-to-discharge LOS was 4 days (IQR 4-8), with one markedly prolonged admission (23 days) due to a sacral pressure injury after a prolonged waiting time before entering the operating room because of organizational issues. After a median follow-up of 16 months (IQR 14-20), explantation was performed in 1 out of 12 cases (8.3%) at 6 months because the scrotal surgical wound persistently failed to heal. Across 12-month follow-up, bladder-related PROMs (SF-Qualiveen and ICIQ-UI SF) and bowel function (NBD score) remained stable overall. IC management showed an improvement in perceived ease of catheterization, significantly advancing (p = 0.006) from median 7 (pre) to 9 (post). Satisfaction and recommendation scores remained high and stable (p > 0.05) over time; at 12 months, medians for satisfaction and recommendation were 9 and 10, respectively. The QoLSPP total and domains scores remained high and stable throughout 12 months (p > 0.05) with a median total score of 67/80 at 12 months. The study collected all the precautions adopted and summarized the adopted pathway into a replicable plan to reduce the risks that other surgeons may need to manage in this population. 5. Discussion In people with SCI/D, IPP implantation should be regarded as the result of a complex selection and optimization pathway. Our referral analysis showed that most patients assessed did not meet appropriateness criteria, indicating that early triage tools such as SCI/D-RAPPS could help limit unnecessary evaluations and focus specialists on those most likely to benefit. Among implanted patients, satisfaction was high and remained stable over time, while bladder and bowel PROMs did not worsen. This suggests that, in carefully selected patients managed within a specific setting, three-piece IPP can provide effective sexual rehabilitation without compromising other pelvic functions. The improvement observed in IC ease is particularly relevant in SCI/D, where the catheterization technique often has a major impact on independence. As for complications, a patient with a high comorbidity burden required explantation because of persistent scrotal wound dehiscence. Although the patient remained afebrile and repeated swabs were negative, the clinical course raised suspicion of an underlying chronic infection. Other possible contributing factors were also considered, including an altered inflammatory or immune response in the setting of chronic idiopathic urticaria, mechanical factors related to obesity in paraplegia with pump prominence and scrotal friction possibly altering wound healing. Overall, these observations support the need for a precise strategy to reduce the risks that covers pre-operative optimization, intra-operative measures and structured post-operative follow-up. 6. Conclusions In a specialized Spinal Unit, the use of a structured pre-, intra- and post-operative pathway was associated with low complication rate, high patient satisfaction, stable bladder and bowel PROMs and easier IC insertion after IPP implantation in carefully selected men with SCI/D. These findings underscore the value of a multidisciplinary approach. The high rate of inappropriate referrals among screened patients also suggests that SCI/D-RAPPS may be a useful referral-support tool to improve patient selection. In addition, the proposed risk-mitigation plan may help surgeons address the specific technical and clinical challenges of IPP surgery in people with SCI.