Ver el código de «Spaceflight testicular torsion»

==Background==
* Testicular torsion is a true urologic emergency in the setting of acute scrotal pain, accounting for the most significant cause of testicular loss.<ref>Velasquez J, Boniface MP, Mohseni M. Acute Scrotum Pain. In: StatPearls [Internet]. Treasure Island, FL: StatPearls Publishing; May 8, 2023.</ref>

* Testicular torsion accounts for 10-15% of acute scrotal illness in children within the United States.<ref>Sharp VJ, Kieran K, Arlen AM. Testicular torsion: diagnosis, evaluation, and management. Am Fam Physician. 2013;88(12):835-840.</ref>

* Peak incidences of testicular torsion are during the neonatal period (first 30 days of life) and puberty (10-14 years). The majority of cases occur during the adolescent age range but can occur at any age.<ref>Huang WY, Chen YF, Chang HC, Yang TK, Hsieh JT, Huang KH. The incidence rate and characteristics in patients with testicular torsion: a nationwide, population-based study. Acta Paediatr. 2013;102(8):e363-e367. doi:10.1111/apa.12275</ref>

* No documented cases of testicular torsion have occurred during spaceflight, likely due to the demographic composition of current spaceflight crews.<ref>Jones J, Pietrzyk RA, Cristea O, Whitson PA. Chapter 18: Renal and Genitourinary Concerns. In: Barratt MR, Baker  E, Pool SL, eds. Priciples of  Clinical Medicine for Spaceflight. Springer  Nature; 2020.</ref>

==Clinical Features==
* Subjective symptoms:
** Abrupt onset of severe testicular and/or lower abdominal pain
** Nausea and vomiting 

* Physical exam findings:
** Swollen and tender testis with or without lower abdominal tenderness
** Non-tender spermatic cord  
** Abnormal position of the testis:
*** Scrotal elevation (high-riding testis)
*** Abnormal transverse position 
*** Undescended testes (predisposes to testicular torsion)
** Absent cremasteric reflex
*** Absent reflex: Light stroking of the inner thigh does not elicit testicular elevation on the ipsilateral side.
*** Intact reflex: Light stroking of the inner thigh elicits testicular elevation on the ipsilateral side.
**** Intact reflex suggests an alternative diagnosis but does not rule out testicular torsion.
** Negative Prehn sign 
*** Negative sign = elevation of scrotum does not relieve pain.
*** Positive sign = elevation of scrotum relieves pain (suggestive of epididymitis).

==Differential Diagnosis==
{{Testicular DDX}}
{{Space medicine}}

==Evaluation==
* Conduct a focused history and physical examination, assessing the abdomen and testes for pain, swelling, abnormal positioning, or tenderness, while documenting the onset, severity, and progression of symptoms.

* Use the multi-study-validated TWIST scoring system, in which a higher score correlates with a greater probability of testicular torsion.<ref>Sheth KR, Keays M, Grimsby GM, et al. Diagnosing Testicular Torsion before Urological Consultation and Imaging: Validation of the TWIST Score. J Urol. 2016;195(6):1870-1876. doi:10.1016/j.juro.2016.01.101</ref>:
** Hard testis - 2
** Swelling - 2
** Nausea/vomiting - 1
** Absent cremasteric reflex - 1
** High riding testis - 1


''100% positive predictive value if score >5''.

''100% negative predictive value if score <2''.

''Scores 2-5 require Ultrasound for further evaluation''.


* Match the patient’s clinical presentation with the characteristic symptoms and peak incidence periods of testicular torsion in adolescents and young adults.

* Recognize that a strong clinical suspicion of torsion requires urgent action due to the narrow window for testicular salvage.

===Workup===
* Duplex ultrasound of the scrotum 
** The linear array “L12-5” probe onboard the ISS is gold standard for evaluation of superficial anatomical structures.<ref>Jones J, Pietrzyk RA, Cristea O, Whitson PA. Chapter 18: Renal and Genitourinary Concerns. In: Barratt MR, Baker  E, Pool SL, eds. Priciples of  Clinical Medicine for Spaceflight. Springer  Nature; 2020.</ref>
** The probe’s spectral and color Doppler performance at shallow depths will enable evaluation for suspected testicular torsion.<ref>Jones J, Pietrzyk RA, Cristea O, Whitson PA. Chapter 18: Renal and Genitourinary Concerns. In: Barratt MR, Baker  E, Pool SL, eds. Priciples of  Clinical Medicine for Spaceflight. Springer  Nature; 2020.</ref>	 	 	 		
* Urine dipstick (available in pre-packaged ISS and Space Shuttle medical kits)

===Diagnosis===
* Testicular torsion is primarily a clinical diagnosis, but point-of-care ultrasound serves as the key diagnostic modality beyond the physical examination. 

* Characteristic findings on ultrasound:
** Enlarged testis
** Twisting of spermatic cord (whirlpool sign)<ref>McDowall J, Adam A, Gerber L, et al. The ultrasonographic "whirlpool sign" in testicular torsion: valuable tool or waste of valuable time? A systematic review and meta-analysis. Emerg Radiol. 2018;25(3):281-292. doi:10.1007/s10140-018-1579-x</ref>
** Reduced or absent central blood flow to/from the affected testis<ref>University of Arkansas for Medical Sciences. Testicular Torsion. UAMS Department of Radiology</ref>
** Heterogenous appearance of testicular parenchyma indicates testicular necrosis<ref>McDowall J, Adam A, Gerber L, et al. The ultrasonographic "whirlpool sign" in testicular torsion: valuable tool or waste of valuable time? A systematic review and meta-analysis. Emerg Radiol. 2018;25(3):281-292. doi:10.1007/s10140-018-1579-x</ref>

* Leukocytes and erythrocytes in the urine suggest epididymitis, orchitis, or urinary tract infection but does not exclude torsion. 

* Laboratory studies are not routinely indicated.

==Management==
* Testicular torsion ideally requires emergent exploratory surgery to salvage the testis. Clinical suspicion of testicular torsion likely necessitates the termination of spaceflight or deorbit to facilitate access to a location equipped with an operating room. However, the time required for space travelers to return to Earth—and subsequently reach an operating room—poses a significant challenge to timely intervention for testicular salvage.
** For those who present within the first 6 hours of symptoms, the salvage rate is nearly 100%, but this number quickly drops to less than 50% if the delay in seeking help is more than 12 to 24 hours.<ref>Howe AS, Vasudevan V, Kongnyuy M, et al. Degree of twisting and duration of symptoms are prognostic factors of testis salvage during episodes of testicular torsion. Transl Androl Urol. 2017;6(6):1159-1166. doi:10.21037/tau.2017.09.10</ref>

* Manual testicular detorsion may be attempted prior to surgery for immediate pain relief or if surgery is not available, but should not delay transferring the patient to the operating room. 
** Procedure:
*** Step 1 - Rotate the testis laterally toward the thigh
*** Step 2 - If lateral rotation does not provide symptom relief, rotate the testis toward the midline<ref>Sharp VJ, Kieran K, Arlen AM. Testicular torsion: diagnosis, evaluation, and management. Am Fam Physician. 2013;88(12):835-840.</ref>

* Exploratory surgery involves untwisting the affected testis (reduction) and securing both the affected and unaffected testes in place with orchiopexy. Orchiectomy is recommended if the testis is grossly necrotic or nonviable.

==Disposition==
* Sudden, severe, unilateral scrotal pain in a patient with a tender, abnormally positioned testis on examination should be managed as testicular torsion until proven otherwise. 

* Testicular torsion is a true urologic and spaceflight emergency requiring timely identification to prevent the need for amputation.

* Ultrasound is the gold standard imaging modality to evaluate scrotal contents for suspected torsion.

* Testicular torsion is an arising and significant concern as spaceflight becomes more accessible to younger individuals, including children and adolescents.

==See Also==
*[[Testicular torsion]]
*[[Testicular diagnoses]]
*[[Testicular ultrasound]]

==References==
<references/>

[[Category:Space Medicine]]