Endoscopic Exploration of a Brachial Plexus Injury

The management of closed brachial plexus injuries is a clinical and surgical challenge. Patients' evaluation is based on repeated clinical examination, neurophysiologic studies and radiologic methods. The clinical data serve to select the group of patients who should undergo surgical exploration, which is the best method to identify lesions and to guide therapeutic decisions. Even though we can find in the literature some reports of endoscopic nerve harvesting,[1] [2] [3] to our knowledge there has been no publication of an endoscopic approach in closed brachial plexus injuries in living human subjects. We found in the comments section of Krishnan and colleagues' paper[4] an invited commenting surgeon who reported only that he had treated two cases of serious iatrogenic lesions of the brachial plexus following endoscopic procedures. The aim of this paper was to report a case of closed brachial plexus injury managed by endoscopic exploration and neurolysis, with a favorable evolution.

A 40-year-old male patient sustained a closed lesion of the brachial plexus following a motorcycle accident. There were no associated fractures and no signs of vascular injury. The clinical picture was that of a paralysis of Duchenne-Erb (compromise of roots C5-C6). The clinical examination revealed a complete paralysis of the muscles-deltoid, supraspinatus, infraspinatus, brachialis, and biceps-as well as sensory loss in the dermatomes corresponding to C5 and C6 (thumb and index). There was no compromise of the serratus anterior, romboid, and diaphragm. There was a deficit of shoulder abduction and forward flexion and also of elbow flexion and wrist extension (partial). Electromyography performed 30 days after the injury revealed lesions of roots C5-C6. The patient presented mild-to-moderate pain completely relieved with opiates. A magnetic resonance imaging (MRI) study of the rootlets revealed no radiologic signs of avulsion or rupture.

Forty days after the accident, there was no clinical or electromyographic sign of reinnervation, so we decided to surgically explore the brachial plexus.

The patient was placed in a dorsal decubitus position and his head was positioned in hyperextension and turned in an opposite direction to the injured plexus. Three incisions of 2.0 cm were made. The first one (medial) was placed at the point where the external jugular vein joins the subclavian vein. The second one (superior) was made at the anterior border of the trapezius muscle. The third incision (lateral) was placed at ± 5 cm from the first incision just above the clavicle. (Figs. [1-3]). After a limited dissection in a sub-platysmal plane, a Foley catheter was introduced in the dissected area and vigorously inflated until a mechanical undermining was produced. The catheter was then deflated and progressed forward and reinflated. This sequence was carried out until a satisfactory dissection of the supraclavicular area was achieved.

Figure 1 Trajectory of the external jugular vein. (Cr: cranial; An: anterior; Po: posterior; Ca: caudal)

Figure 2 Three ports (superior, medial and lateral). (Cr: cranial; An: anterior; Po: posterior; Ca: caudal)

Figure 3 Skin appearance after surgery.

The endoscope was then introduced in the lateral incision. A dissection forceps was introduced in the superior incision and scissors in the medial one. The dissection was then carried out under direct vision. The instruments that were utilized included blunt curved and tapering scissors, bipolar cautery forceps, dissection forceps, a suction shaft, and a retractor integrated with an optic system. We used rigid 0° and 30° cameras (STORZ™) connected to a digital video recorder. The endoscopic tower was the same one used for every other endoscopic procedure at our hospital. After the introduction of the camera, we cautiously started the dissection of the profound structures in the same way we do in the open approach. The phrenic nerve was identified, the omohyoid muscle was divided, and the trunks of the brachial plexus identified. The brachial plexus was entirely explored. Visualization with the endoscope was magnified and the dissection could be performed very precisely. We carried out an external neurolysis of the plexual structures because no signs of rupture or avulsion were found.

The immediate postoperative period was free of complications. The patient had complete recovery of sensibility and all affected muscular groups after 6 months.

There are contradictory factors involved in the assessment of closed brachial plexus injuries. Most surgeons agree that a period of clinical observation from 2 to no longer than 6 months should take place to allow the identification of patients who will have a spontaneous recovery. On the other hand, patients presenting ruptures or root avulsions must be surgically treated as early as possible, because no spontaneous improvement is expected. This is the reason why some centers favor shorter intervals before performing brachial plexus explorations.

We agree with Krishnan et al.[4] that endoscopic exploration might be a method that would couple the advantages of a less invasive technique with the precision of direct vision. In that study, they showed the feasibility of endoscopic exploration of the brachial plexus in human fresh cadavers. Monsivais and colleagues[5] have shown the feasibility of visualizing and documenting avulsed rootlets by an endoscopic approach in goats. They stated that with refinements of technique and instrumentation, it would be possible to perform repairs, transfers, and implantation of avulsed rootlets in patients.

We believe this report confirms the feasibility of brachial plexus endoscopic exploration in a clinical setting. Many other studies are needed before the role of this new method can be established. We intend not to modify our current indications for surgical exploration. However, we will initiate the endoscopic technique in selected cases in which we can expect that the anatomy will not be distorted. In case of significant technical difficulty, we will convert the procedure into an open exploration. We think that in this manner, we will be able to gain the needed experience to define the role of this technique in brachial plexus injuries.

REFERENCES

• 1 Capek L, Clark H M, Zuker R M. Endoscopic sural nerve harvest in the pediatric patient.  Plast Reconstr Surg. 1996;  98 884-888
• 2 Xu W D, Gu Y D, Ian L J. Full length phrenic nerve transfer by means of video-assisted thoracic surgery in treating brachial plexus avulsion injury.  Plast Reconstr Surg. 2002;  110 104-111
• 3 Chuang D C, Mandini S. Extended phrenic nerve transfer [letter].  Plast Reconstr Surg. 2003;  112 354-356
• 4 Krishnan K G, Pinzer T, Reber F et al.. Endoscopic exploration of the brachial plexus: technique and topographic anatomy. A study in fresh human cadavers.  Neurosurgery. 2004;  54 401-408
• 5 Monsivais J J, Narakas A O, Turkof E et al.. The endoscopic diagnosis and possible treatment of nerve root avulsions in the management of brachial plexus injuries.  J Hand Surg. 1994;  19B 547-549