What are long-term mechanical failure rates by manufacturer for 3-piece versus 2-piece penile implants?
Executive summary
Three-piece inflatable penile prostheses (3-piece IPPs) show high short- and mid-term mechanical survivability but measurable component-failure and revision rates emerge over longer follow-up; reported survivorship for IPPs is roughly 87% at 5 years and falls to about 53% by 20 years [1] [2]. Two-piece IPPs and malleable (semi‑rigid) devices tend to have fewer moving parts and in many series show lower mechanical failure or higher survival than 3-piece devices, though head-to-head, contemporary comparisons are limited and heterogeneous [3] [4].
1. Three-piece IPPs: strong early survival, predictable late attrition
Multiple observational series and narrative reviews report that modern 3‑piece IPPs are durable in the medium term with mechanical survival commonly >87% at 5 years and device survivability estimated at roughly 96% at 5 years, 86% at 10 years and ~53% at 20 years in pooled or cited cohorts [1] [5] [2]. Device-specific reports show varying mechanical failure proportions—for example, one single‑center series found 20.6% of patients with an AMS 700 experienced mechanical failure over a median ~82 months, while other larger pooled analyses report far lower revision frequencies depending on cohort and follow‑up [3] [6]. The pattern is consistent: good short-term reliability, with cumulative wear‑and‑tear (tube or junction leaks, pump or cylinder failures) driving rising mechanical failure and revision rates over time [1] [7].
2. Two‑piece IPPs and malleable devices: fewer parts, lower mechanical-failure signal in some series
Two‑piece IPPs (Ambicor and similar designs) and malleable rods have fewer mechanical components and several studies and reviews have recorded lower mechanical failure rates or higher survival compared with older three‑piece series; reported mechanical failure rates for Ambicor/two‑piece systems range from about 0.7% to 6.1% in literature summaries and targeted reviews [4]. Malleable prostheses are described repeatedly as mechanically simpler and therefore less prone to mechanical failure than inflatable systems in multiple reviews [8] [9], although they carry tradeoffs in cosmesis and patient preference [3] [8].
3. Manufacturer‑level signals: AMS (Boston Scientific), Coloplast, Rigicon — wide ranges and study dependence
Comparative, manufacturer‑stratified data are heterogeneous. A systematic review found AMS 700® removal rates spanning 0.3% to 52.9% across studies, while Coloplast Titan® removal rates were reported between 0% and 6.2% in the same review; Rigicon’s Infla 10® had low mechanical failure of roughly 2–3% in short follow‑up series [10]. Other series report similar 5‑year mechanical survival for AMS and Coloplast (for example, 5‑year Kaplan‑Meier mechanical survival approximated 91% for AMS 700 CX vs 87% for Titan in one cohort, without statistical significance) [11]. These manufacturer comparisons are confounded by center experience, patient selection, era of device design, and follow‑up duration [10] [7].
4. Why the numbers vary: study design, follow‑up, and evolving device iterations
Apparent disparities in mechanical failure rates by implant type or brand are driven by multiple methodological factors: many analyses pool different eras of device design (older models had markedly higher cylinder and tubing failures), follow‑up durations vary widely, and single‑center series can produce extreme removal ranges that skew pooled ranges [1] [7] [10]. Meta‑analytic estimates show device survival declining with time (93% at 1 year to 53% at 20 years), illustrating that “failure rate” depends critically on the time window studied [2]. Reviews emphasize that contemporary antibiotic‑coated and reinforced tubing models improved early and mid‑term reliability compared with historic devices [1] [7].
5. Bottom line, and limits of the evidence
The best available contemporary evidence supports that 3‑piece IPPs have excellent early mechanical survival (>87% at 5 years) but accumulate failures over decades (about half functioning at 20 years), while two‑piece IPPs and malleable devices often show lower mechanical failure rates in many series because they are mechanically simpler [5] [2] [4] [8]. Manufacturer‑specific failure/removal ranges exist (AMS ranges wide across studies; Coloplast generally lower in pooled reports; Rigicon low in short series) but are inconsistent across datasets and strongly influenced by study selection, device generation, and follow‑up length [10] [11]. Publicly available literature does not supply a single definitive manufacturer‑by‑manufacturer long‑term mechanical failure table that adjusts for era, center volume, and patient mix; this limitation tempers any simple headline claim.