Radiofrequency (RF) Generators, Electrodes, and Cannulas for Pain Management and Neurosurgery - Cosman Medical

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Treat Sacroiliac Joint Pain For Cost Two RF Cannulae

The Palisade^TM technique makes treatment of pain from sacroiliac joint (SIJ) dysfunction easier, faster, and less expensive than ever before. It employs recent discoveries in Bipolar radiofrequency (RF) technology to create larger lesions than in cooled RF SIJ treatments, using smaller, less expensive RF cannulae and electrodes. Scientific evaluation of the technique predicts a more complete SI Joint lesion zone that conforms to patient anatomy and is less likely to leave gaps between adjacent lesions that could allow painful nerves to remain.¹

Bipolar RF Creates Larger Lesions that Cooled RF

The Palisade approach employs overlapping bipolar RF lesions to create an aggregate lesion zone that traverses the entire region that sacral lateral branch nerves travel to the SI Joint.  Since bipolar lesions have an elongated "brick like" rectangular shape that is robust to parallel cannulae spacings of 8-12 mm (Figure 2), a lesion zone with substantially consistent thickness and height can be created using by lowering relatively few standard cannulae straight to the sacral surface.  In contrast, cooled RF methods use multiple, smaller spherical lesions that produce a total lesion zone with variable height and thickness, and which will have gaps that could spare painful nerves (see Figure 1).^1,3

Figure 1 (A) Cooled monopolar lesion geometry for 10 and 12 mm tip-to-tip spacings, 2 mm tip-to-sacrum distance, 60°C set temperature, and 3.25-minute lesion time (0.75 pre-cooling + 2.5 heating).^2,3,4 Gaps between and around adjacent lesions situated near the sacral surface can arise from small increases in tip-to-tip and tip-to-sacrum distances. (B) Bipolar lesion geometry for 10 mm and 12 mm tip-to-tip spacings, 0 mm tip-to-sacrum distance, 90°C set temperature, and 3-minute lesion time. Individually, bipolar lesions can be larger than both cooled and noncooled monopolar lesions. When arranged in a palisade on the sacral surface, bipolar lesions can collectively produce a lesion zone of consistent height, width, and depth that has fewer gaps than the lesion zone produced by the reported cooled RF SIJ method. (C) Three monopolar lesions, created using 90°C set temperature and 3-minute lesion time, are required to approximate a single bipolar lesion for 10 mm tip spacing and the same RF parameters (shown by the dotted outline). (A–C) Each panel shows a set of thermal lesions in both lateral (top) and needle (bottom) views.¹

Straight-Line Ease and Efficiency

In the Palisade procedure¹, cannulae are placed in a straight line between the sacral foramina and the ipsilateral SIJ line.  The line can be chosen using an AP x-ray image without additional measurement equipement, even in the presence of bowel gas.  In contrast, for periforaminal techniques like that used with cooled RF, each sacral foramina must be accurately identified and electrodes placed at specific positions and distances relative to each foramina^2,3,4.  Use of additional reference needles^2,3 and an epsilon rulers³ are advocated by some for these placements.

Multi-Bipolar for Even Faster Procedures

With standard reusable electrodes, the Palisade procedure can be performed efficiently and at very low cost using only two standard disposable RF cannulae.  Using up to six cannulae and the G4 four-electrode generator reduces procedure time even more, since multiple bipolar lesions are generated at the same time.  The Palisade Kit includes disposable cannulae and disposable electrodes to perform the Palisade procedure as described in the literature¹.

The Confidence of Bony Contact

Since Palisade Cannulae remain in contact with the sacral surface through placement and lesioning, you can ensure that placements conform to patient anatomy over the length of the sacrum.  And, you can avoid placements within the sacral foramina which could pose a risk to the sacral nerve roots.

Compare to Cooled RF Point by Point

Compare the SIJ pain treatment using the Cosman Palisade kit with that using the Kimberly-Clark/Baylis SInergy® kit in terms of ease of use, effectiveness, treatment time, equipment requirements, patient trauma, and cost.  The following table is dervived from peer-reviewed scientific literature on the subject^1,2,3,4, published specifications, promotional material, and bench testing.  As shown below, procedure time can be even further reduced by energizing multiple bipolar pairs at once using the Cosman G4 four-electrode radiofrequency generator.

The Palisade Kit

The Palisade kit is designed for bipolar RF treatment of pain due to sacroiliac joint dysfunction.  The contents of each kit can support a either one four-electrode, six-cannulae treatment, or two two-electrode, three-cannulae treatments:

• Six straight RF cannulae (10 cm shaft length, 10 mm tips, 20 or 18 gauge)
• Four disposable RF electrodes
• The CB114-TC reusable cable is provided separately.

Bipolar RF is a Powerful New Tool for Pain Management

For many years, parallel Bipolar radiofrequency has been used for pain treatment in the SIJ and other anatomy^9,10,11,12, and recent scientific discoveries show that Bipolar RF is a powerful tool for creating large RF heat lesions, with dimensions that can even exceed 20 mm (see Figure 2). When employing radiofrequency heat lesioning with lesions of any size, a physician must always excise his own independent clinical judgement judgement in selecting a lesion size that is appropriate to the target anatomy to avoid undesired damage to senstive structures.

Figure 2. Cross-sectional photographs of bipolar lesions in ex vivo adult bovine liver show the lesion lengths L and widthsWproduced by different parallel tip spacings, tip diameters, and tip lengths, for 90°C tip temperature and 3-minute lesion time. The "Depth Cross Section" photograph shows two bipolar lesions in the lower liver slab, revealed by cutting the lower liver slab in a plane perpendicular to the tip lengths. Half of their midline depth dimension D can be measured in this manner. ¹

1. Cosman ER Jr, Gonzalez CD. Bipolar Radiofrequency Lesion Geometry: Implications for Palisade Treatment of Sacroiliac Joint Pain. Pain Practice 2011; 11(1): 3-22.  [PDF]  [Pain Practice]  [PubMed]
2. Wright RF, Wolfson LF, DiMuro JM, Peragine JM, Bainbridge SA. In vivo temperature measurement during neurotomy for SIJ pain using the Baylis SInergy probe. International Spine Intervention Society 15th Annual Scientific Meeting; 2007: 82–84.  This reference notes that the maximum tissue temperature is not measured by the SInergy probe.
3. Kapural L, Nageeb F, Kapural M, Cata JP, Narouze S, Mekhail N. Cooled radiofrequency system for the treatment of chronic pain from sacroiliitis: the first case-series. Pain Pract. 2008;8:348–354.
4. Cohen SP, Hurley RW, Buckenmaier III CC, Kurihara C, Morlando B, Dragovich A. Randomized placebocontrolled study evaluating lateral branch radiofrequency denervation for sacroiliac joint pain. Anesthesiology. 2008; 109:279–288.  This reference notes that an 9th lesion is placed at S4 if it is suspected to be involved in the pain syndrome.
5. 6 minutes = (3 minutes)*(2 sessions of 2 bipolar lesions at once).  9 minutes = (3 minutes)*(2 sessions of 2 bipolar lesions at once + 1 session of 1 bipolar lesion).
6. 12 minutes = (3 minutes)*(4 bipolar lesions).  15 minutes=(3 minutes)*(5 bipolar lesions).
7. 26 minutes = (3:15 minutes)*(8 cooled lesions). 29:15 minutes = (3:15 minutes)*(9 cooled lesions).
8. The Kimberly-Clark/Baylis® Pain Management RF Generator (PMG) pushes water through the cooled RF probe for 45 seconds before RF is activated, and only one electrode is energized at a time, as shown in the video viewable on the manufacturer's website http://www.baylismedical.com/VideoLibrary/Pages/PMG_3_sinergy.html
9. Cosman Sr ER, Rittman WJ, Nashold BS, Makachinas TT. Radio frequency lesion generation and its effect on tissue impedance. Appl Neurophysiol. 1988;51:230–242.
10. Ferrante FM, King LF, Roche EA, et al. Radiofrequency sacroiliac joint denervation for sacroiliac syndrome. Reg Anesth Pain Med. 2001;26:137–142.
11. Pino CA, Hoeft MA, Hofsess C, Rathmell JP. Morphologic analysis of bipolar radiofrequency lesions: implications for treatment of the sacroiliac joint. Reg Anesth Pain Med. 2005;30:335–338.
12. Burnham RS, Yasui Y. An alternate method of radiofrequency neurotomy of the sacroiliac joint: a pilot study of the effect on pain, function, and satisfaction. Reg Anesth Pain Med. 2007;32:12–19.
13. A 17-gauge cannula has a cross-sectional area that is (1.47 mm / 1.27 mm)² = 134% that of an 18-gauge cannula, and (1.47 mm / 0.9144 mm)² = 258% that of a 20-gauge cannula. Therefore, for the same depth of insertion, a 17-gauge cannula displaces more than 2.5 times as much tissue as a 20-gauge cannula.

* Kimberly-Clark, ThoraCool, TransDiscal, TransDiscal System, SInergy, SInergy System are trademarks or registered trademarks of Kimberly-Clark Worldwide, Inc.
* Baylis, Baylis Medical, BMC are a trademarks or registered trademarks of Baylis Medical Company, Inc. or Kimberly-Clark Worldwide, Inc.