Management of Recurrent Stingers
Introduction
Stingers, characterized by unilateral arm weakness, are seen in up to 65% of football players (1). In an NCAA study, they found that the highest incidence of stingers occurred with making a tackle and blocking (4). The pathophysiology regarding a stinger is a downward depressed shoulder with cervical spine side-bending away from the shoulder, leading to stretching of the C5 or C6 nerve (1). Debate exists whether a stinger is due to C5 or C6 nerve root injury or a brachial plexus injury (1). EMG studies have identified injuries to the cervical nerve roots, brachial plexus, and peripheral nerves in patients diagnosed with a stinger (3). Recurrent stingers in a single season require further evaluation (5).
Diagnosis
The symptoms of a stinger typically occur immediately after a hit and typically involve a burning pain that radiates down the arm in a non dermatomal distribution (2). The athlete may also have weakness and numbness in the upper extremity that typically resolve in seconds to minutes (2). Classification of a stinger is based on the Seddon and Sunderland classification (7). Grade 1 injuries are a nerve stretch injury that give transient symptoms, grade 2 involve injury to axons and myelin sheath which cause symptoms that last up to two weeks, and grade 3 symptoms are complete nerve root transection which can lead to permanent damage (7).
Important in the diagnosis of a stinger is differentiating a stinger from a spinal cord injury (1). Any patient complaining of stinger like symptoms in 2 or more extremities should be evaluated for cervical spine injury (1).
A chronic stinger syndrome typically involves symptoms that last greater than 24 hours (2). Patients with prolonged stinger symptoms and those with more than two stingers in a season need an evaluation of their cervical spine (5). Typically, athletes with recurrent stingers will have narrowing of the cervical neural foramen or degenerative disk disease (5). Measurement of the cross-sectional area of the cervical spine is a predictor of neurologic injury following cervical spine trauma (3). Several imaging-based calculations, such as the Torg ratio and the mean subaxial cortical space available for the cord (MSCSAC), can be used to predict the risk of cervical spine injury (2). The Torg ratio compares the midsagittal diameter of the spinal cord to the vertebral body diameter on a plane radiograph (3). The MSCSAC requires an MRI and will take into count soft tissue stenosis (4).
Measurement of the Torg ratio a/b as a measurement for spinal stenosis (3)
Treatment
Prevention of recurrence is the main treatment for an acute stinger. Athletes should be educated on tackling technique and potentially lifting their shoulder pads to prevent neck hyper-extension (1). A Kerr collar tries to minimize head acceleration forces through the cervical spine (5). For more prolonged symptoms, a prescription for physical therapy is appropriate with a focus on cervical and shoulder strengthening (1).
Use of a Kerr collar with football pads (6)
Athletes with three or more stingers in a season should undergo radiographic evaluation of their cervical spine prior to return to play (4). They should also undergo an EMG if persistent weakness lasts greater than two weeks prior to return to play (7).
Treatment algorithm for stingers (7)
Conclusion
Stingers are transient sensory and motor loss in one extremity that typically occur after a traumatic hit. Symptoms typically self-resolve, but those symptoms that are persistent or recurrent require further evaluation. Imaging studies of the cervical spine and EMG both aid in evaluation of recurrent stingers and for those with persistent weakness. Return to play should be individualized based on physical examination, imaging studies, and EMG results.
By Gregory Rubin, DO
Rubinsportsmed.com
– Read More @ Wiki Sports Medicine: https://wikism.org/Cervical_Cord_Neuropraxia
References
1) Safran, Marc R. “Nerve Injury about the Shoulder in Athletes, Part 2: Long Thoracic Nerve, Spinal Accessory Nerve, Burners/Stingers, Thoracic Outlet Syndrome.” The American Journal of Sports Medicine, vol. 32, no. 4, June 2004, pp. 1063–76. PubMed, https://doi.org/10.1177/0363546504265193.
2) Greenberg, Jared, et al. “Predicting Chronic Stinger Syndrome Using the Mean Subaxial Space Available for the Cord Index.” Sports Health, vol. 3, no. 3, May 2011, pp. 264–67. PubMed, https://doi.org/10.1177/1941738111403866
3) Castro, F. P., et al. “Stingers, the Torg Ratio, and the Cervical Spine.” The American Journal of Sports Medicine, vol. 25, no. 5, Oct. 1997, pp. 603–08. PubMed, https://doi.org/10.1177/036354659702500503
4) Green, James, et al. “A 6-Year Surveillance Study of ‘Stingers’ in NCAA American Football.” Research in Sports Medicine (Print), vol. 25, no. 1, Mar. 2017, pp. 26–36. PubMed, https://doi.org/10.1080/15438627.2016.1258642
5) Zaremski, Jason L., et al. “Recurrent Stingers in an Adolescent American Football Player: Dilemmas of Return to Play. A Case Report and Review of the Literature.” Research in Sports Medicine (Print), vol. 25, no. 3, Sept. 2017, pp. 384–90. PubMed, https://doi.org/10.1080/15438627.2017.1314297
6) New collar helps protect young football players from head and neck injuries – ABC13 Houston
7) Ahearn, Briggs M., et al. “Traumatic Brachial Plexopathy in Athletes: Current Concepts for Diagnosis and Management of Stingers.” The Journal of the American Academy of Orthopaedic Surgeons, vol. 27, no. 18, Sept. 2019, pp. 677–84. PubMed, https://doi.org/10.5435/JAAOS-D-17-00746
