Treatment of debilitating cremasteric synkinesia with intracremasteric botulinum-A toxin injections

To describe the surgical technique of botulinum-A toxin injection into the cremasteric muscles of a 26-year-old male with bilateral cremasteric muscle spasms causing significant pain and limitation of activity. This pain has been refractory to multiple previous therapies, including inguinal nerve blocks and bilateral orchidopexies with cremasteric muscle lysis. Multiple imaging modalities revealed no obvious pathology for this significant bilateral pain. Genitourinary examination revealed hyper-retractile testes with changes consistent with bilateral orchidopexies and was otherwise normal.

The patient has undergone 3 outpatient staged injections of botulinum-A toxin into the bilateral cremasteric muscles after spermatic cord block with 1% lidocaine. One hundred units of botulinum-A toxin mixed into 10 mL of sterile normal saline were used for each injection staged 6 weeks apart.

The patient tolerated all injections without apparent side effects. After the first injection into his left side, his baseline pain scores were reduced from 8 out of 10 to 3 out of 10 on a standard 10-point pain scale. He reported maximal efficacy 2 weeks after each injection, with dissipation over 4-6 weeks. After 2 left-sided and 1 right-sided injections, his baseline pain was 2 to 4 of 10, equal bilaterally, and he was back to rigorous activity with some limitations.

Direct injection of botulinum-A toxin into the cremasteric muscle is a viable treatment option for the rare patient with debilitating and painful cremasteric spasms refractory to other therapies.