PI is an urgent situation. If treated untimely, it can result in devastating consequences, as the persistent constriction might lead to genital vascular occlusion, further causing skin loss, urethral-cutaneous fistula, erectile dysfunction, and even penile loss. Given that no particular tool has been designed for relieving the strangulation, and occasionally the patient is too old with severe comorbidities, a multidisciplinary team, sometimes including firefighters, physicians, and scrubbing nurses, is suggested to be established.
Albeit cases of penial strangulation and its treatments had been sporadically reported, there are no universal treating protocols due to the differences in patients' status, strangulating objects, and medical conditions. Various objects could induce the strangulation of the penis. Based on the material, they could be roughly classified as metallic and non-metallic. Trivedi et al suggested that the duration of incarceration was an essential factor affecting the prognosis. Namely, suppose the penile strangulation cannot be relieved in time, it may lead to irreversible ischemic necrosis, gangrene of the penis, even penile self-amputation, urethral fistula, and penile erectile dysfunction.
As far as we are concerned, the penis injury can be divided into different grades, varying from edema, skin loss, urethral fistula to complete amputation, that is: Grade 1: simple distal prepuce edema without penile skin ulcer or urethral injury; Grade 2: skin injury and cavernous compression, penile prepuce edema, accompanied by decreased sensation, but no urethral injury; Grade 3: urethral injury, loss of distal penile sensation, but no urinary fistula; Grade 4: the rupture of the cavernous urethral body and result in urinary fistula, further compression of the penile cavernous body with loss of sensation; and Grade 5: necrosis or spontaneous disconnection of the distal end of the penis. In our experience, anti-infection and decompression are basic principles to deal with such cases. At the same time, the severity of strangulation is mainly related to the foreign object itself, such as hardness, size, and smoothness. More specifically, when the surface between the incarcerating object and the penis is not smooth or too tight, the penis would present acute edema, ulcer, and even necrosis. However, long-term strangulation may only cause edema of the prepuce and local skin superficial ulcer when the incarceration is not severe, rather than penial necrosis and urinary fistula. This situation might be partial because, at this time, penial and urethral cavernous bodies are shielded from edematous skins.
Generally, the treatment attempts we take should minimize the trauma to local tissues. Applying lubricating oil with appropriate traction to remove foreign objects directly is preferred. For those with severe incarceration and noticeable swelling, penis piercing could be performed. The piercing sites could be either the edematous skin, the subcutaneous skin, or the penial and urethral cavernous body when necessary.
For less-likely removable strangulating objects, direct cutting is recommended. Under these circumstances, the hardness and thickness of the material should be taken into consideration. For non-metallic incarcerations, such as hair tourniquet syndrome, rubber bands for disease prevention, plastic bottles for sexual entertainment, or seal rings, the treatments are reported to be comparatively more straightforward. However, as the strangulating objects had a certain degree of deformability, it is crucial to restore the deformed penis after removing the strangulating objects. Due to the metallic hoop's hardness and thickness, treatments on metallic incarcerations are more complicated. Previous literature mentioned various surgical tools, mostly from orthopedics and dentistry, such as motor-operated emery wheel machine, metal cutter, grinder, hacksaw, fretsaw, industrial-grade steel bolt cutters, and marble cutting tool[4,14,15]. In extreme cases such as strangulation by axletree or hammerhead, cautious planning is needed before violent cutting. The heat originating from the persistent cutting procedure could cause burn injury even with additional irrigation. Subsequently, the operation might be performed in a de-gloving way, which can be decomposed into three steps: (1) De-gloving the skin distal to the strangulated area till the coronal part; (2) Moving the constrictive object towards the distal end; and (3) Suturing the edge of the skin back.
Extra operations are required in exceptional situations, such as PI with shallow ulcerations or urinary tract fistulae. Ulceration indicates the necrosis of penial skin or partial corpus cavernosum. Thereafter, the necrotic part needs to be debrided first. However, if the wound defect is too large to be sutured, a skin graft with radial forearm flap neophallus might be required. If deep necrosis is found in the urethra, partial or entire penectomy might be necessary[9,17,18].
There were three main benefits of using a fretsaw in this case. First, compared with a dental drill and other electric equipment, the initiation, cessation, and alteration of cutting direction could be adjusted more responsively when deploying a fretsaw. Second, there would be no inertia and electric sparks because hands drove the fretsaw. Last but not least, because the cutting direction was from the inner layer to the outer surface, the accidental injury caused by the damage of the metal structure would be avoided.
Nevertheless, the cutting efficiency of using a fretsaw is comparatively low, as it is purely powered by hands. Continuously cutting for several minutes is tiring, and thereafter loss of controllability might occur. Same as other methods, thermal damage could not be avoided. Hence, an assistant must continuously spray normal saline with a syringe to cool the metal surface.
Several limitations should be noted. First, due to the rarity of PI, more cases are awaiting to be summarized to increase credibility and generality. Specific consideration should be taken regarding patient status, the degree of edema, and the material of the incarcerating object. Systematic reviews are called for to establish higher-level evidence. Second, specific steps, in this case, could be optimized, such as a bacterial culture could be performed in case of severe postoperative skin infection, and the postoperative daily observation of the wound might be better recorded.