An update on penile prostheses: a narrative review

Abstract

Men with erectile dysfunction offered penile prostheses have high satisfaction rates when properly counselled. These devices have undergone significant advancements in design, surgical techniques, and perioperative management, enhancing patient outcomes, satisfaction, and safety. This review summarizes the latest innovations, including novel non-antimicrobial prevention strategies and disposable surgical tools that may reduce infection risks. Furthermore, advances in operative techniques, including safer alternative reservoir placement, have minimized the complications. Additionally, innovations in postoperative management, such as multimodal analgesia and nerve blocks, have improved patient recovery and comfort. Lastly, emerging technologies, including shape-memory alloys and electronic-controlled devices that represent potential future breakthroughs are described.

INTRODUCTION

Since they were first offered in clinical practice over 50 years ago, penile prostheses (PP) have been continuously refined with key innovations to enhance reliability, safety, and patient satisfaction.1 Patient and partner satisfaction is generally excellent, but several key areas where techniques and outcomes may be improved remain. These developments are underpinned by new data and innovation that continue to guide clinical practice. Many advances may merit discussion, but for the purposes of this review, several key areas will be highlighted with emphasis on developments over the last 10 years. This narrative review serves as an update on these developments for implanters who understand the topical issues in PP surgical care.

For the most part of the last 50 years, the industry has been dominated by two key device companies, Boston Scientific (Marlborough, MA, USA; previously American Medical Systems [AMS]) and Coloplast (Minneapolis, MN, USA; previously Mentor Corporation). The past decade has seen two new device companies emerge in the market. Both Zephyr Surgical Implants (Geneva, Switzerland) and Rigicon Incorporated (Ronkonkoma, NY, USA) remain niche companies, but both have brought significant innovations to the field deserving of mention.

Infection remains a devastating complication in PP surgery.2 Infection retardant coated devices introduced in 2001 proved revolutionary by decreasing the risk of infection following PP insertion.3 However, this has changed the biofilm associated with these prosthetic devices and the organisms commonly associated with device infection. Fungal infections are reported in over 10% of patients, but these are not covered by contemporary antimicrobial prophylaxis. Hence, the current understanding on antifungal prophylaxis and the use of 0.05% chlorhexidine gluconate (CHG) solution are summarized. Disposable tools like the Furlow may also play a role in preventing infectious complications.

Surgical techniques and best practice for PP insertion also continue to advance. The key steps of the operation, like reservoir placement and the use of surgical drains, remain a point of debate among implanters. There have also been recent innovations for difficult surgical cases like severe corporal fibrosis and the attenuated (or missing) tunica albuginea. The insertion of a PP (or more correctly an erectile device) for masculinizing gender affirmation surgery remains one of the most challenging cases for the implanter.4 Again, recent developments in devices and surgical technique are explored.

This narrative review was conducted to summarize the latest innovations in PP surgery. A comprehensive search of MEDLINE and Embase databases was performed for English language studies published from August 2014 to August 2024. The search terms included combinations of “penile implants” OR “penile prosthesis” OR “malleable prosthesis”. Articles were screened for relevance based on title, abstract, and full text. Additional studies were identified within the bibliography of screened references.

An updated search was conducted on January 2025, to ensure the inclusion of the most recent publications. The inclusion criteria were as follows: (1) congress abstracts, case reports, case series, retrospective, or prospective studies focusing on innovations in surgical techniques or advancements in devices and (2) studies reporting surgical techniques, functional outcomes, and complications associated with innovative procedures or device developments. The exclusion criteria were as follows: (1) studies evaluating PP surgery outcomes without specifying the surgical technique or incorporating new devices or (2) literatures lacking the clear documentation of outcomes or surgical methods.

UPDATE ON PENILE PROSTHESIS DESIGN

AMS pioneered the development of inflatable penile prosthesis (IPP) in 1973, and a decade later, Coloplast, which acquired Mentor in 2006, emerged as AMS’s first major competitor. The last 10 years has seen two new device companies enter the market with significant innovations in the devices offered. Nevertheless, the incumbents also continue to bring new products and modifications to market.

Rigicon Inc.

The Rigicon Infla10® is a new IPP introduced to the global market in 2019. Manufactured by Rigicon Inc. (Ronkonkoma, NY, USA), the Infla10® is currently available only in international markets, but it is not yet approved for use in the USA. Initial safety outcomes for the Rigicon Infla10® reported no infections but a re-operation rate of 4.3% mostly due to mechanical failure after a mean follow-up of 21 months.5 The malleable version, Rigicon Rigi10®, has demonstrated impressive early safety in a multicenter study involving 605 patients. It showed no mechanical failures, and revision or removal surgery was required in <1% of cases after a mean follow-up of 21.6 months.6 Rigicon also markets the Infla10X and InflaAX, two IPPs with significant advancements in girth expansion and both girth and length expansion, respectively.

Zephyr Surgical Implants (ZSI)

ZSI, based in Switzerland, introduced the ZSI 475 IPP and the malleable implants ZSI 100 and ZSI 100CF. Design and manufacturing improvements have reduced the rate of mechanical failure for the ZSI 475 IPP.7 Zephyr is also the only manufacturer currently producing devices specifically designed for transgender male-to-female (FtM) and genital reconstruction, known as the “FTM” models, discussed in a following section.4,8 Rigicon offers a lifetime replacement warranty, while Zephyr’s ZSI 475 is priced approximately 30% lower than competing products, which may enhance its competitiveness with well-established IPP manufacturers such as Boston Scientific and Coloplast.7

Boston Scientific

On the other side, the established companies have also participated of new developments. AMS 700™ TENACIO™ Pump from Boston Scientific was recently approved by the U.S. Food and Drug Administration (FDA). It offers easier manipulation, and it has an independent valve function for inflation and deflation, which seems likely to decrease pump failures.9 The “Optimized Tubing Length (OTL)” penoscrotal penile implant kits have additional tubing length, which avoid alternative techniques to increase tubing length (such as the additional rear tip extenders or the use of infrapubic implants to make their own tubing connections).10

The new-generation malleable prosthesis from Boston Scientific, Tactra™, was introduced in 2019. It has a bend flexibility of 120° due to a dynamic Nitinol core encased by a proprietary dual-layer silicone exterior which provides device rigidity.11 There have been no studies reporting outcomes following Tactra insertion except for a published abstract from the 20^th Annual Fall Scientific Meeting of SMSNA. Eleven patients in this multicenter report overall high satisfaction with the implant, particularly due to its more natural glans contour. However, implant concealability appeared to decrease with the 11-mm and 13-mm devices compared to the 9-mm ones. Additionally, three patients experienced a slight “S” deformity.12

UPDATE ON INFECTION PREVENTION

The introduction of the “no-touch” technique by Eid et al.13 two decades ago was a major milestone in reducing infections during PP implantation. By preventing any contact between the implant and skin, infection rates dropped significantly. 13 Since then, further innovations have continued to build on this foundation, enhancing safety and long-term outcomes.

Use of antifungal prophylaxis

The rate of infection after PP implantation ranges from 1% to 3% and it remains one of the most devastating and therefore feared complications of this surgery.2 The three most prevalent organisms cultured during salvage of an infected IPP are Escherichia coli (18.3%), followed by coagulase-negative Staphylococcus species (15%), and Candida species (11.1%).14 Fungal infections are more prevalent in patients with diabetes (with no correlation to glycated hemoglobin [HbA1c]) and obesity.15,16 Although climate has been anecdotally associated with an increased risk of infections due to the changes in the skin microbiome, a recent study has shown that no consistent relationship exists between the climate at time of PP placement and PP infection risk.17 The addition of an anti fungal for prophylaxis (by coating the device and to irrigate the wound) was effective in retrospective studies reported at conferences.18,19 The Current American Urological Association (AUA) and European Association of Urology (EAU) prophylaxis guidelines do not incorporate the use of antifungals for prophylaxis as the body of literature to date is not robust enough.16,20 However, the cost of a prophylactic dose of anti fungals in all patients undergoing implant surgery in the UK is less than the cost of a single revision procedure for device infection. Therefore, routine use has been recommended by expert opinion, particularly in patients at high risk for a fungal infection, such as obese and diabetic patients.20 Additionally, dipping devices in an anti fungal solution have been shown not to compromise the effectiveness of the current antimicrobial solutions used in clinical practice.21

Non-antimicrobial prophylaxis and lavage

Irrisept antimicrobial wound lavage (Irrimax Corporation, Lawrenceville, GA, USA) consists of 0.05% chlorhexidine gluconate (CHG) in sterile water that is aseptically filled and then sterilized by ethylene oxide.22 It has been used in other prosthetic surgical disciplines, such as orthopedic or breast reconstructive surgery to irrigate the prosthesis.23,24 In vitro studies showed that CHG is effective against the most common species associated with PP infections (Gram positive, Gram negative, aerobic, anaerobic, and fungal organisms).25 In a recent review, Irrisept was evaluated and compared on a preclinical and clinical basis, with povidone iodine (PVI) and hydrogen peroxide (H₂O₂). Of all 3 agents, H₂O₂ showed the most deleterious effects on tissues, without better coverage to pathogens than PVI or CHG, and therefore, its use is no longer recommended.26 Although dilute PVI has the highest level of clinical evidence in support of its use in prosthetic surgery, CHG is likely to be a promising agent that seemingly surpasses PVI.26 However, the likelihood of infection may be lower when irrigating during PP insertion with vancomycin/gentamicin solution27,28 due to better adherence of the solution to the hydrophilic coating of devices. The 0.05% CHG, followed by normal saline irrigation, removed all dip solution previously adherent to the implant hydrophilic surface.

Revision surgery following a previous PP placement has a significantly higher risk for infection compared to primary cases, with the devices found to harbor a subclinical bacterial presence isolated in the surrounding biofilm.29 Therefore, it is important in revision surgery to carry out a vigorous mechanical lavage of the wound and surgical spaces to remove biofilm using antimicrobial irrigation (to eradicate bacterial colonization).30 Irrisept has been used in vivo for salvage procedures in 4 patients, showing good results after 7 months’ follow-up.31 These early promising data remain to be confirmed in prospective trials to determine not only the infection rates but also the long-term device functionality after irrigation.22

Implanters continue to face the dilemma of how to sterilize the distal urethra during PP insertion. Lack of sterilization means that surgery is generally aborted following a distal urethral injury. A proprietary chloraexidine gel was used for preoperative urethral instillation in a study of 111 patients undergoing andrological surgery. After instillation, the chlorhexidine gel group did not grow any organisms on urethral and skin samples (contrary to the controls). This suggests that urethral preparation with 6 ml of chlorhexidine gel may adequately sterilize the distal urethra and allow primary repair of a distal urethral injury with simultaneous implantation of a PP. Again, more high-powered multi-center studies are necessary to confirm this interesting hypothesis.32

Disposable tools

The Furlow is an integral tool for the insertion of an IPP. However, the very design of the tool may complicate the cleaning and sterilization process. Around 2.4% of the traditional Furlow Insertion tools were found to have positive swab cultures for Staphylococcus epidermidis.33 In order to reduce the risk of infection during implantation, a disposable Furlow insertion tool has been designed.33,34 However, head-to-head studies comparing this disposable tool with traditional Furlow insertion tools are necessary to determine whether postoperative infection rates differ significantly. Concerns regarding the environmental impact of adding to the burden of disposable equipment and packaging following PP insertion also need to be addressed by cost-benefit analysis.

UPDATE ON SURGICAL TECHNIQUES AND BEST PRACTICE

Reservoir fixation or placement

The reservoir of an IPP is traditionally placed retropubic into the space of Retzius (SOR). Despite the demonstrated safety of this single incision approach, concerns remain regarding the blind passage of the reservoir through the floor of the inguinal canal, due to the close proximity of the external inguinal ring to vital structures that could be injured during the blind passage of the reservoir.35

Using a second incision for intraperitoneal placement of the reservoir is a reasonable option in select patients.36 Also, a counter incision for ectopic placement has recently demonstrated similar safety and efficacy to the standard SOR, minimizing the risk of complications.37,38 In an effort to avoid the potential morbidity associated with a second incision, Wilson et al.39 described in 2002 the placement of the reservoir in the anterior abdominal wall musculature through the same incision. To further facilitate this technique, thinner reservoirs were designed to enable easier placement in the anterior abdominal wall. In 2011, Perito and Wilson40 introduced an alternative ectopic placement technique, positioning the reservoir preperitoneally, either posterior or anterior to the transversalis fascia (PTF or ATF), using an infrapubic approach.

More recently, other alternatives to the traditional SOR placement have been described and may offer a safe, effective, and reproducible technique.41,42,43 One of the main issues related to “ectopic” placement is the potentially higher incidence of reservoir migration.44 Therefore, different techniques to address this potential complication have been proposed in the literature (Table 1).45,46,47,48,49,50,51,52

Table 1.

Recent reported innovations in reservoir placement

Technique	Study	Procedure	Patient (n)	Follow-up (month)	Palpable/visibility (%)	Migration/herniation (%)	Malfunction (%)	Infections (%)	Injuries (%)
“Five-Step” technique for HSM	Baumgarten et al.45 2020 Baumgarten et al.46 2020 Osmonov et al.47 2020	Position and access Develop lower HSM pocket Develop upper HSM pocket Reservoir delivery (fill and fine-tune) Confirm and connect	297	10a	14	1	-	-	0
Sub-external oblique reservoir placement	Garber et al.48 2019	The reservoir is placed between the external and internal oblique fascias and muscles where there are no significant structures that can be damaged	50	6.6 (3–12)b	2	0	-	-	0
MSMR	Zisman et al.49 2022	Performed through the scrotal incision, dissecting at the level of the rectus fascia, which was entered sharply using a tonsil clamp at 4 cm above the pubis and lateral to the linea alba. A blunt separation of the rectus muscle is carried out to create a submuscular space between the rectus muscle and its posterior sheath. As the reservoir is embedded within the muscle, it is less likely to herniate or become palpable to the patient	48	28a	-	0	4	0	0
DVT	Kava et al.50 2022	The reservoir is placed anterior to the transversalis fascia under direct vision taking advantage of the elastic properties of the scrotal skin and exposing the anterior rectus sheath. The rectus fascia is directly pierced and the fibers of the rectus muscles are bluntly separated	100	17.5±20.5c	0	1	4	4	0
THALIA technique	Yang et al.44 2021	Securing the tubing and reservoir. Prior to connecting the reservoir and pump tubing, a 2-0 Ethibond on a CT-1 needle is used to take a generous bite of tissue over the pubic bone and left untied (Hitch). One end of the stitch is threaded through an extra tubing collar (Lasso). The newly placed reservoir tubing is threaded through the above collar so the tubing and Ethibond are adjacent and both go through it. Next the Ethibond is tied down affixing it to the pubic bone (anchored). The reservoir cannot migrate downward into the scrotum as the lock out valve will stop at the collar	35	5a	-	0	-	0	0
Low submuscular reservoir placement with transfascial fixation	Khoei et al.51 2022	The reservoir is placed between the rectus muscle and the transversalis fascia. The fascia is used to anchor the balloon and tubing in place	31	15–34d	25.8	0	0	0	0
Prof. van Renterghem technique	Mykoniatis et al.52 2020	Placing the reservoir through the external oblique muscle fascia to gain access into the classical SOR. Fascia is closed after placement with a Vicryl-1 stay suture to avoid migration	253	9.1 (3–22)b	0	0	0	0	0

^aMean; ^bmedian (IQR); ^cmean±s.d.; ^drange. -: no value; IQR: interquartile range; s.d.: standard deviation; HSM: high submuscular; CT-1: circle taper-1; THALIA: Tubing, Hitch And Lasso, Intussusception Anchor; MSMR: midline submuscular placement; DVT: direct vision transfascial; SOR: space of Retzius

Use of surgical drains

Postoperative bleeding and hematoma formation can complicate the insertion of an IPP leading to infection, device malfunction, and poor satisfaction. To manage these complications, postoperative measures typically include the application of a compressive dressing (mummy wrap) and most recently, the wider use of close suction drainage (CSD). The use of CSD may reduce the incidence of postoperative hematomas without increasing the risk of infection.53,54 A recent multi-center prospective study conducted in 345 patients showed that the early postoperative infection rate was the highest in patients without drain (4.4%) and the lowest in the 72-h CSD group (0.9%), although with no statistically significant differences. The presence of hematoma at 24 h post-surgery was significantly associated with the likelihood of infection.55 Based on these findings, CSD should be considered for all patients undergoing IPP insertion to help reduce hematoma formation and the potential risk of infection.

Surgical strategies for the prevention and management of distal cylinder erosion

One of the most challenging aspects of PP revision surgery is managing obliteration or attenuation of the corpora cavernosa, often resulting from severe corporal fibrosis, poorly treated infections, or prior device erosion. To support or reconstruct the corporal bodies during such procedures, the use of a lightweight macroporous mesh (poliglecaprone-25/polypropylene mesh or UltraPro) has been proposed as a promising alternative to traditional graft materials.56 In a complex patient cohort undergoing revision surgery (following multiple previous revisions), this technique showed an acceptable infection rate of 5%.56 This technique has been successfully combined with both malleable and inflatable PP.57,58 Additionally, polypropylene mesh (Ethicon, Cincinnati, OH, USA) has been used in combination with malleable implants to enhance rod girth, particularly in cases where standard prosthetic diameters were insufficient. Prior to the availability of 14-mm malleable rods (now offered by Rigicon), the “Ghattas technique” was developed to augment girth by wrapping a 13-mm prosthesis with a polypropylene mesh sleeve. In a series of 23 patients, this approach demonstrated no infections over a mean follow-up of 5.5 months.59

In a similar vein, the Distal Biologic Cap (DBC) technique involves the reinforcement of the distal tunica albuginea using a biological graft, typically at least 1 mm in thickness, or alternatively, autologous tissue such as tunica vaginalis, fascia lata, or saphenous vein.60

For cases involving undersized implants or distal complications, the Proximal Extracapsular Tunneling (ECT) technique offers a minimally invasive solution. It involves the creation of a new proximal extracapsular tract that enables proper cylinder repositioning without the need to reopen the distal corpora, thus potentially reducing surgical morbidity.61

Finally, the Distal Corporal Anchoring Stitch addresses malpositioned or laterally extruding cylinders. Through a lateral sub-coronal incision, dissection is carried through Buck’s fascia, followed by a transverse tunical incision to expose the distal cylinder tip. A 4-0 PDS suture is passed through the distal cylinder ring and into a newly created intracorporal channel. The suture exits through a small cruciate incision in the glans, where it is anchored and buried subcutaneously, ensuring proper cylinder alignment and preventing lateral extrusion or crossover in patients with distal corporal compromise.62

Novel instruments

Shaeer and Shaeer63 have introduced a forward-cutting cavernotome, a hollow metal tube with a cutting edge at the tip, designed to operate on the principle of coring and grinding rather than forward thrusting, thereby reducing the risk of perforation. In a prospective study of 18 patients with severe corporal fibrosis, the device enabled successful corporal dilation within minutes, enhancing both the safety and efficacy of prosthesis implantation in challenging cases.63 Unlike Rosselló’s cavernotome and the Uramix (Mooreville dilator), Shaeer’s device does not require a forward-thrusting or stabbing motion, as its cutting blades are positioned at the tip rather than laterally, making it theoretically safer. However, currently available published data remain limited.

UPDATE ON GENDER-AFFIRMING SURGERY

PP insertion in transgender and gender diverse individuals following phalloplasty present unique challenges due to anatomical differences compared to cisgender males. The neophallus lacks a corpora cavernosa and tunica albuginea, leading to insufficient anchorage, lower vascularization, and decreased stability. Moreover, the absence of the native corpora cavernosa leaves the cylinders unprotected, which heightens the risk of implant migration, mechanical failure, and instability. Standard prostheses are designed for cisgender anatomy and may not effectively meet the needs of this population.64 In order to address the need for proximal fixation of penile implants, some fixation techniques have been described, including the placement of the cylinders directly against the pubic bone, suturing the rear tip extender to the pubic bone, drilling holes in the superior surface of the pubic bone or suturing to the anterior surface of the pubic bone a sock of nonabsorbable material such as Dacron or Gore-Tex or cadaveric pericardium (Tutoplast®).8,65,66

The Zephyr 475FTM implant was subsequently developed specifically for individuals assigned female at birth (AFAB). This novel inflatable device features an enhanced area for pubic bone fixation, a realistically shaped glans at the distal end, and a testicle-shaped pump.64 Initially, this implant demonstrated lower complication rates compared to previous literature, during a short follow-up period.64 However, with a longer follow-up and a larger number of patients, the same group published similar data to other prosthetic devices. The report presented complications in 53.1% of the cases, mostly due to mechanical dysfunction (40.0%) or infection (6.2%), with no significant differences between primary (virgin) and revision prosthesis insertion. The 4-year survival probability of primary implantation of prostheses was 75.5%.67 Studies on malleable prosthesis (ZSI 100FTM) in 25 AFAB individuals also revealed high complication rates, with a 36% explantation rate during the first 6 months after surgery.68

Despite these recent advancements, most of the literature indicates that many centers continue to offer the standard IPPs but often with one cylinder inserted rather than two.8,69 This necessitates the use of tailored techniques (such a Dacron cap and sock) to accommodate the distinct anatomical features of AFAB individuals.

UPDATE ON POSTOPERATIVE MANAGEMENT

Pain management strategies are critical to optimize patient satisfaction and increasingly, enhanced recovery after surgery (ERAS) protocols for implant surgery in an outpatient setting are being instituted where adequate analgesia is critical. Moreover, there is a drive to reduce opioid-based analgesic regimens due to the opioid epidemic.70

Patients receiving a multimodal analgesia protocol which included intra-operative pudendal nerve block (PNB) for IPP implantation required fewer narcotics both during inpatient hospitalization and post-discharge.71 PNB is also an attractive option not only to minimize the perioperative needs of opioids but also to maximize pain control and post-operative narcotic use.72,73

OTHER FUTURE DEVELOPMENTS

The “rumor” of a “remote-controlled” PP that may be activated without the need for a manual pump continues to circulate, although there have been limited official announcements by the device companies. It is known that work continues in an effort to bring such a device to market.

In 2019, a shape memory alloy “touchless” PP designed to achieve a set shape from magnetic induction was reported as an alternative to hydraulic-based PP.74 This prosthesis, consisting of a temperature-tuned nickel titanium alloy, was implanted in both an animal model and in several cadavers in the “flaccid” state and then activated using an external magnetic inducer wand. The device was activated within 45 s, a reasonable time for the patient to obtain an erection without interrupting intimacy, with a small increase in skin temperature at the implant site not noticeable to the patient. Moreover, the external wand/inductor is potentially easier to use and can be operated by patients with dexterity problems, such as those with severe arthritis. Long-term safety, ease of activation on demand, maximal obtainable rigidity, and prevention of unwanted activation from exposure to magnetic fields (e.g., with magnetic resonance imaging [MRI]) remain major issues that will need to be resolved for this form of implant.74

A semi-automatic inflatable electronic PP prototype has been developed. The prototype integrates an electronic control system that allows activation via a mobile device, eliminating the need for manual pumping. However, due to resource limitations, the full adaptation of the electronic system to the physical model has not yet been completed.75

DISCUSSION

The field of PP has undergone significant advancements over recent years, reflecting innovation in design, functionality, and clinical applications over the last 50 years. This is integral for patient outcomes to improve. Underpinning these advances are the device companies that manufacture and market PP. It is encouraging that new products and innovations are now offered by Zephyr and Rigicon. Importantly, the incumbents Boston Scientific (AMS) and Coloplast (Mentor) also continue to innovate, meaning that the diverse needs of select patient groups such as transgender and gender diverse individuals are increasingly recognized and addressed.

Similarly, surgical innovation continues to minimize the complications associated with PP surgery. Alternative reservoir placement techniques have emerged as a safer and more versatile approach compared to the traditional retropubic placement. Techniques such as supramuscular, submuscular, and ectopic reservoir placements have shown promise in minimizing the complications such as vascular or organ injury. However, head-to-head comparison studies are required to gain a more robust understanding of the benefits (and risks) of the alternative techniques. Other innovations such as the use of lightweight macroporous mesh, disposable tools, and the Shaeer cavernotome all add to the armamentarium available to the implanter particularly when faced with a challenging case.

To reduce the risk of prosthetic infections, a novel dipping and irrigation solution of 0.05% CHG and intraurethral instillation of chlorhexidine shows promise. Also, broader use of antifungal prophylaxis, particularly in diabetic patients and revision cases, is increasingly accepted. Again, more robust data are required before addition to the society guidelines and routine clinical practice. Perioperative analgesic management with multimodal analgesia deserves recognition for improving patient outcomes and satisfaction.

In conclusion, the field of PP surgery continues to grow and innovate. New entrants in the market and the established device manufacturers remain focused on improving outcomes with new products and instruments. Complex cases are better managed with novel surgical techniques and strategies, with improved patient outcomes. Hence, it remains as important as ever for implanters to keep abreast with these developments to ensure that their practice remains contemporary.

AUTHOR CONTRIBUTIONS

WGL initiated the study concept and design. CP and WGL acquired the data. CP analyzed the data. CP and DR drafted the manuscript. All authors read and approved the final manuscript.

COMPETING INTERESTS

All authors declare no competing interests.