Carlos E. Restrepo and Robert J. Spinner
Andrés A. Maldonado and Robert J. Spinner
Spinal accessory nerve (SAN) injury results in loss of motor function of the trapezius muscle and leads to severe shoulder problems. Primary end-to-end or graft repair is usually the standard treatment. The authors present 2 patients who presented late (8 and 10 months) after their SAN injuries, in whom a lateral pectoral nerve transfer to the SAN was performed successfully using a supraclavicular approach.
Robert J. Spinner, John L. D. Atkinson, and Robert L. Tiel
Object. Based on a large multicenter experience and a review of the literature, the authors propose a unifying theory to explain an articular origin of peroneal intraneural ganglia. They believe that this unifying theory explains certain intriguing, but poorly understood findings in the literature, including the proximity of the cyst to the joint, the unusual preferential deep peroneal nerve (DPN) deficit, the absence of a pure superficial peroneal nerve (SPN) involvement, the finding of a pedicle in 40% of cases, and the high (10–20%) recurrence rate.
Methods. The authors believe that peroneal intraneural lesions are derived from the superior tibiofibular joint and communicate from it via a one-way valve. Given access to the articular branch, the cyst typically dissects proximally by the path of least resistance within the epineurium and up the DPN and the DPN component of the common peroneal nerve (CPN) before compressing nearby SPN fascicles. The authors present objective evidence based on anatomical, clinical, imaging, operative, and histological data that support this unifying theory.
Conclusions. The predictable clinical presentation, electrical studies, imaging characteristics, operative observations, and histological findings regarding peroneal intraneural ganglia can be understood in terms of their origin from the superior tibiofibular joint, the anatomy of the articular branch, and the internal topography of the peroneal nerve that the cyst invades. Understanding the controversial pathogenesis of these cysts will enable surgeons to perform operations based on the pathoanatomy of the articular branch of the CPN and the superior tibiofibular joint, which will ultimately improve clinical results.
Robert J. Spinner, Robert L. Tiel, and David G. Kline
Jonathan J. Stone, Megan C. Kaszuba, and Robert J. Spinner
Patients who present with a history of cancer and the new onset of lumbosacral or peripheral neuropathy should be evaluated for the potential of metastasis. Targeted fascicular biopsy can be useful to diagnose atypical lesions within peripheral nerves in patients with major or progressive neurological deficits. In this video, the authors demonstrate the technique of targeted fascicular biopsy of the sciatic nerve in a 63-year-old man with a history of prostate cancer.
The video can be found here: https://youtu.be/PTOX9XxNBDU.
Robert J. Spinner, Jay U. Howington, and David G. Kline
Andrés A. Maldonado, Benjamin M. Howe, and Robert J. Spinner
Paralysis of the posterior interosseous nerve (PIN) secondary to compression is a rare clinical condition. Entrapment neuropathy may occur at fibrous bands at the proximal, middle, or distal edge of the supinator. Tumors are a relatively rare but well-known potential cause. The authors present 2 cases of PIN lesions in which compression by a benign lipoma at the level of the elbow resulted in near transection (discontinuity) of the nerve. They hypothesize a mechanism—a “sandwich effect”—by which compression was produced from below by the mass and from above by a fibrous band in the supinator muscle (i.e., the leading edge of the proximal supinator muscle [arcade of Fröhse] in one patient and the distal edge of the supinator muscle in the other). A Grade V Sunderland nerve lesion resulted from the advanced, chronic compression. The authors are unaware of a similar case with such an advanced pathoanatomical finding.
Mark A. Mahan, Kimberly K. Amrami, and Robert J. Spinner
Kimon Bekelis, Symeon Missios, and Robert J. Spinner
Despite the growing epidemic of falls, the true incidence of peripheral nerve injuries (PNIs) in this patient population remains largely unknown.
The authors performed a retrospective cohort study of 839,210 fall-injured patients who were registered in the National Trauma Data Bank (NTDB) between 2009 and 2011 and fulfilled the inclusion criteria. Regression techniques were used to investigate the association of demographic and socioeconomic factors with the rate of PNIs in this patient population. The association of age with the incidence of PNIs was also investigated.
Overall, 3151 fall-injured patients (mean age 39.1 years, 33.3% females) sustained a PNI (0.4% of all falls). The respective incidence of PNIs was 2.7 per 1000 patients for ground-level falls, 4.9 per 1000 patients for multilevel falls, and 4.5 per 1000 patients for falls involving force. This demonstrated a rapid increase in the first 2 decades of life, with a maximum rate of 1.1% of all falls in the 3rd decade, followed by a slower decline and eventual plateau in the 7th decade. In a multivariable analysis, the association of PNIs with age followed a similar pattern with patients 20–29 years of age, demonstrating the highest association (OR 2.34 [95% CI 2.0–2.74] in comparison with the first decade of life). Falls involving force (OR 1.25 [95% CI 1.14–1.37] in comparison with multilevel falls) were associated with a higher incidence of PNIs. On the contrary, female sex (OR 0.87 [95% CI 0.80–0.84]) and ground-level falls (OR 0.79 [95% CI 0.72–0.86]) were associated with a lower rate of PNIs.
Utilizing a comprehensive national database, the authors demonstrated that PNIs are more common than previously described in fall-injured patients and identified their age distribution. These injuries are associated with young adults and falls of high kinetic energy.
Hannah E. Gilder, Ross C. Puffer, Mohamad Bydon, and Robert J. Spinner
In this study, the authors sought to compare tumors with intradural extension to those remaining in the epidural or paraspinal space with the hypothesis that intradural extension may be a mechanism for seeding of the CSF with malignant cells, thereby resulting in higher rates of CNS metastases and shorter overall survival.
The authors searched the medical record for cases of malignant peripheral nerve sheath tumors (MPNSTs) identified from 1994 to 2017. The charts of the identified patients were then reviewed for tumor location to identify patients with paraspinal malignancy. All patients included in the study had tumor specimens that were reviewed in the surgical pathology department. Paraspinal tumors with intradural extension were identified in the lumbar, sacral, and spinal accessory nerves, and attempts were made to match this cohort to another cohort of patients who had paraspinal tumors of the cranial nerves and lumbar and sacral spinal regions without intradural extension. Further information was collected on all patients with and without intradural extension, including date of diagnosis by pathology specimen review; nerve or nerves of tumor origin; presence, location, and diagnostic date of any CNS metastases; and either the date of death or date of last follow-up.
The authors identified 6 of 179 (3.4%) patients who had intradural tumor extension and compared these patients with 12 patients who harbored paraspinal tumors that did not have intradural extension. All tumors were diagnosed as high-grade MPNSTs according to the surgical pathology findings. Four of 6 (66.7%) patients with intradural extension had documented CNS metastases. The presence of CNS metastases was significantly higher in the intradural group than in the paraspinal group (intradural, 66.7% vs paraspinal, 0%; p < 0.01). Time from diagnosis until death was 11.2 months in the intradural group and approximately 72 months in the paraspinal, extradural cohort.
In patients with intradural extension of paraspinal MPNSTs, significantly higher rates of CNS metastases are seen with a reduced interval of time from diagnosis to metastatic lesion detection. Intradural tumor extension is also a poor prognostic factor for survival, with these patients showing a reduced mean time from diagnosis to death.