ABSTRACT: Anterior interosseous nerve syndrome is characterized by paralysis of the flexor digitorum profundus, the flexor pollicis longus and the pronator quadratus muscles without sensory loss. Extended exploration of the anterior interosseous nerve is the surgical treatment of choice. The present study evaluates the feasibility of an endoscopic approach for nerve decompression.
Preparation of the anterior interosseous nerve was performed in ten human cadaver arms. Subsequently, one female patient suffering from anterior interosseous nerve syndrome was endoscopically operated on.
A skin incision of 3-4 cm in the proximal direction was made at the forearm, and the median nerve was visualized between the pronator teres muscle and the flexor digitorum superficialis. Subsequently, the anterior interosseus nerve branch was identified, followed distally and decompressed under endoscopic view. The procedure could be accomplished in all cases under endoscopic view. Due to the very steep surgical angle, a branch of the anterior interosseus nerve was injured in one cadaver case. In all other cases, no adverse effects were observed. In the clinical case, the anterior interosseus nerve was endoscopically identified and decompressed, but a skin incision of 5 cm was required.
The results demonstrate that an endoscopic decompression of the anterior interosseus nerve is possible. Several difficulties occurred: Due to the depth of the surgical approach, especially in case of bulky muscles and very small skin incisions, the view is limited, harboring a higher risk of nerve injury. With more experience and specially designed endoscopes, application of this technique in anterior interosseus nerve compression syndrome might become more feasible.
Acta Neurochirurgica 07/2011; 153(11):2225-9. · 1.52 Impact Factor
ABSTRACT: Water jet dissection represents a promising technique for precise brain tissue dissection with preservation of blood vessels. In the past, the water jet dissector has been used for various pathologies. A detailed report of the surgical technique is lacking.
The authors present their results after 208 procedures with a special focus on surgical technique, intraoperative suitability, advantages, and disadvantages.
Between March 1997 and April 2009, 208 patients with various intracranial neurosurgical pathologies were operated on with the water jet dissector. Handling of the device and its usefulness and extent of application were assessed. The pressures encountered, potential risks, and complications were documented. The patients were followed 1 to 24 months postoperatively.
A detailed presentation of the surgical technique is given. Differences and limitations of the water jet dissection device in the various pathologies were evaluated. The water jet dissector was intensively used in 127 procedures (61.1%), intermittently used in 56 procedures (26.9%), and scarcely used in 25 procedures (12%). The device was considered to be very helpful in 166 procedures (79.8%) and helpful to some extent in 33 procedures (15.9%). In 8 (3.8%) procedures, it was not helpful, and in 1 procedure (0.5%), the usefulness was not documented by the surgeon.
The water jet dissector can be applied easily and very safely. Precise tissue dissection with preservation of blood vessels and no greater risk of complications are possible. However, the clinical consequences of the described qualities need to be demonstrated in a randomized clinical trial.
Neurosurgery 12/2010; 67(2 Suppl Operative):342-54. · 2.79 Impact Factor
ABSTRACT: Although waterjet dissection has been well evaluated in intracranial pathologies, little is known of its qualities in peripheral nerve surgery. Theoretically, the precise dissection qualities could support the separation of nerves from adjacent tissues and improve the preservation of nerve integrity in peripheral nerve surgery.
To evaluate the potential of the new waterjet dissector in peripheral nerve surgery.
Waterjet dissection with pressures of 20 to 80 bar was applied on the sciatic nerves of 101 rats. The effect of waterjet dissection on the sciatic nerve was evaluated by clinical tests, neurophysiological examinations, and histopathological studies up to 12 weeks after surgery.
With waterjet pressures up to 30 bar, the sciatic nerve was preserved in its integrity in all cases. Functional damaging was observed at pressures of 40 bar and higher. However, all but 1 rat in the 80 bar subgroup showed complete functional regeneration at 12 weeks after surgery. Histopathologically, small water bubbles were observed around the nerves. At 40 bar and higher, the sciatic nerves showed signs of direct nerve injury. However, all these animals showed nerve regeneration after 12 weeks, as demonstrated by histological studies.
Sciatic nerves were preserved functionally and morphologically at pressures up to 30 bar. Between 40 and 80 bar, reliable functional and morphological nerve regeneration occurred. Waterjet pressures up to 30 bar might be applied safely under clinical conditions. This technique might be well suited to separate intact peripheral nerves from adjacent tumor or scar tissue. Further studies will have to show the clinical relevance of these dissection qualities.
Neurosurgery 12/2010; 67(2 Suppl Operative):368-76. · 2.79 Impact Factor
ABSTRACT: Simple decompression in ulnar nerve compression syndromes offers options for endoscopic applications.
The authors present their initial experience with the Agee device.
The monoportal endoscopic technique (Agee system) was evaluated on 10 cadaveric arms. Subsequently, 32 arms of 29 patients were operated on between January 2006 and March 2009. All patients presented with typical clinical signs and neurophysiologic studies. Long-term follow-up examinations were obtained in 27 of 32 arms.
In the cadaver study, the ulnar nerve was always correctly identified. No nerve damage occurred, and sufficient decompression of the ulnar nerve was always achieved. In the clinical series, no intraoperative complications were observed. A change to open technique was not required, and no worsening of the cubital tunnel syndrome occurred. Two wound infections required surgical wound cleaning. Wound hematomas treated conservatively were found in 5 cases. On long-term follow-up, an improvement in the McGowan- Classification was achieved in 22 of 27 cases. One patient was operated on by open surgery after endoscopic surgery.
The endoscopic technique for ulnar nerve entrapment syndrome using an Agee device appears to be safe and efficient. The results are comparable to those achieved with simple open decompression. A randomized prospective study should be performed to further evaluate the value of new technique in ulnar nerve entrapment syndrome.
Neurosurgery 06/2010; 66(6 Suppl Operative):325-31; discussion 331-2. · 2.79 Impact Factor
ABSTRACT: Recently, several studies suggested that simple decompression is as effective as anterior transposition in ulnar nerve entrapment syndrome. Simple decompression might be performed with minimally invasive techniques. The authors present their technique and results with endoscopic decompression in ulnar nerve entrapment syndrome.
Between January 2005 and March 2008, 24 patients (mean age, 45.5 years; range, 26-67 years) underwent surgery for 26 ulnar nerve entrapment syndromes (2 bilateral). All patients presented with typical clinical signs and neurophysiologic studies.
Intraoperatively, the ulnar nerve was localized directly at the sulcus, and subsequently under endoscopic view, the decompression was completed approximately 10 cm proximal as well as distal. In 26 cases, a significant compression of the nerve was found directly at and distal to the sulcus. In 1 case, a subluxation of the nerve was observed, the endoscopic technique was abandoned, and open anterior submuscular transposition followed. The procedure was successful in 19 of 22 cases (86%). Neither intraoperative nor postoperative complications were observed. Nevertheless, the identification of the nerve directly at the sulcus, where severe nerve compression was often found, seemed to be difficult and potentially risky, particularly in obese patients.
The endoscopic technique for ulnar nerve entrapment syndrome seems to be safe and effective. However, particularly in patients with a thick subcutaneous fat layer, identification of the nerve at the sulcus is difficult and possible more risky than in open simple decompression. A randomized prospective study should be performed to further evaluate the value of this new technique in the treatment of ulnar nerve entrapment syndrome.
Neurosurgery 04/2010; 66(4):817-24; discussion 824. · 2.79 Impact Factor
ABSTRACT: The long-term efficacy of dual-portal endoscopic release of the transverse ligament in carpal tunnel syndrome is still being debated. In this study, the authors present 94 endoscopic carpal tunnel surgery cases with long-term follow-up data.
The study includes 72 patients aged 17 to 86 years (mean age, 53.4 years); bilateral surgery was performed in 22 of these patients. Seventy-two hands of female patients and 22 hands of male patients were included. All procedures were performed with a dual-portal set according to the Chow technique. All patients were examined 2 to 3 months after surgery. The long-term follow-up evaluation was based on telephone interviews 5 to 12 years (mean, 8.2 years) after surgery.
From a cohort of 214 cases that were treated surgically between 1995 and 2002, 94 cases (44%) could be evaluated for long-term follow-up. Four of these patients had to be excluded from long-term follow-up because of a switch to an open technique and early open revision (3-6 months after the first surgery), owing to persistent symptoms. A good to optimal postoperative outcome with improvement of neurological signs and subjective patient satisfaction was observed in 84 (93.3%) of the remaining 90 cases. There were no recurrences.
The study shows that dual-portal endoscopic release of the transverse ligament in carpal tunnel syndrome is a valuable technique that produces very good long-term results and high patient satisfaction and does not result in a significant recurrence rate.
Neurosurgery 02/2009; 64(1):131-7; discussion 137-8. · 2.79 Impact Factor