Botulinum Toxin Use as an Adjunctive Modality in a Patient with Multiple Flexor Tendon Ruptures

Abstract

Botulinum toxin A has been described in treatment protocols for several disease processes, from primary axillary hyperhydorosis to esophageal dysfunction. It is best known for its use in plastic and dermatological practices. Botulinum toxin has a straightforward mechanism of action. The toxin inhibits acetylcholine release at the neuromuscular junction causing a chemical denervation, which ceases contractions of the muscle. With its minimal side effect profile, botulinum toxin should be considered when muscle spasm is a detriment. This case involves an injury to the hand of a patient with a history of intermittent diffuse muscle spasms. Subsequently, due to the patient's previous upper extremity muscle spasms, repeated flexor tendon repair ruptures of the index finger occurred until botulinum toxin was administered to the offending muscle. The patient has not required any additional surgical interventions for the repaired tendon and is now actively flexing all digits. This case report demonstrates how botulinum toxin can be used in a clinical scenario when decreased muscle activity is desired to promote tendon healing.Keywords Flexor tendon rupture . Botulinum toxin A . Botox . Teno fix . Flexor tendon repair Case ReportA 44-year-old right-hand-dominant male presented to the emergency room with injuries sustained to his left hand owing to a table saw laceration across his palm. His exam and operative findings noted the following: fractures of the index and small finger proximal phalanges, zone III flexor digitorum superficialis and profundus tendon lacerations to the index, zone III flexor pollicis longus tendon laceration, and zone III flexor tendon injuries to the small finger. Concurrent injuries also included digital nerve lacerations to the thumb, index, and small finger. There were vascular lacerations of the digital artery to the small and index fingers.His past medical history is significant due to an ongoing neurological dysfunction from a prior traumatic injury. This prior injury has left the patient with intermittent diffuse muscle spasms. His medications for this condition include neurontin 600 mg four times a day, baclofen 20 mg three times a day, morphine 30 mg three times a day, and celebrex 200 mg twice a day. Despite this regiment of medications, he describes ongoing symptoms of muscle spasm including his injured extremity. His past surgical history is also significant for a prior left middle finger amputation through the level of the middle phalanx.Initial emergent operative management incorporated irrigation and debridement along with repairs of the tendon lacerations to the thumb, index, and small fingers. Tendon repairs were carried out using a four-strand core suture technique augmented with a 6-0 prolene epitendinous suture. The bony fractures were stabilized with 0.045 Kirshner wires. Repairs to the lacerated digital nerves and arteries were also performed. Finally, a protective dorsal block plaster splint was applied.The patient was examined postoperatively in a routine fashion....

Perioperative Botulinum Toxin Injections to Enhance Surgical Outcomes in Patients With Spasticity: Preoperative, Intraoperative, and Postoperative Case Reports

“…The optimal timing for perioperative BoNT is unknown, but different studies have described preoperatively up to 5 weeks presurgery, 6 , 13 , 14 intraoperatively during the surgery, 5 , 15 and postoperatively as early as 1 week post surgery. 19 Our cases demonstrate an important role for perioperative BoNT in patients with spasticity undergoing surgical interventions where their spasticity could affect the surgical outcome.…”

“…Human studies have suggested that perioperative BoNT administration (the perioperative period includes the following 3 time frames: preoperative, intraoperative, or postoperative) 12 may reduce pain, spasticity, and analgesic use in patients with preexisting spasticity. 5 , 6 , 13 , 14 , 15 Similarly, patients undergoing orthopedic procedures unrelated to their spasticity, such as hip replacement for hip dysplasia, wound flap surgery for pressure ulcers, or neck stabilization for cervical myelopathy, may also benefit from perioperative BoNT injections to help with a successful surgical outcome. 5 , 6 , 7 , 16 , 17 , 18 …”

Number of botulinum toxin injections needed to stop requests for treatment for chronic lateral epicondylar tendinopathy. A 1-year follow-up study

“…The primary analgesic effect of BoNT-A is suggested to result from easing the tension in the whole enthesis site, including the tendon [36], thereby resulting in immobilisation of the enthesis. This procedure has been shown to improve the healing process of several tendons [40] [41]. BoNT-A is also said to have an analgesic effect by inhibiting the release of neurotransmitters such as glutamate, substance P and calcitonin gene-related peptide involved in the transmission of tendon pain [42].…”

Canadian Physicians' Use of Perioperative Botulinum Toxin Injections to Spastic Limbs: A Cross-sectional National Survey

“…Perioperative BoNT injection has also led to a reduction of pain and spasticity and a decrease in analgesic use in patients undergoing surgery on their spastic limbs. 17 , 18 , 19 , 20 , 21 Perioperative BoNT injections can also optimize surgical outcomes of patients with spasticity undergoing orthopedic procedures not directly related to their preexisting spasticity, 11 , 17 , 18 , 19 , 20 , 21 , 22 Perioperative BoNT could therefore help improve surgical outcomes, alleviate postoperative pain, and facilitate rehabilitation participation. 11 …”