Arthroscopic Needling Technique for the Treatment of Wrist Ganglia

Abstract

Background  Synovial cysts (SCs) are the most frequent wrist tumors; the arthroscopic treatment presents good results when surgery is indicated for symptomatic or patients with cosmetic concerns. The tumoral lesion should be arthroscopically decompressed or drained toward the inside of the joint through pedicle opening and resection of a small portion of the capsule. Hence, the cyst pedicle must be found for the success of this technique.

Description of Technique  Some tricks have already been described to facilitate SC location during arthroscopy. We describe an indirect technique that employs an 18-G needle to enhance SC pedicle location and drainage. The technique involves a puncture on the interval of the carpal extrinsic ligaments where the pedicle is suspected to be remain. When found, cyst is drained with a single-puncture motion of the need which promotes cyst content extravasation due to pressure toward the joint.

Patients and Methods  This method has been employed in 16 patients, including 9 with dorsal cysts, and seven with volar cysts.

Results  All patients presented complete recovery and symptom improvement in up to 30 days, with total disappearance of the cyst. There were no relapses or severe complications within the 12-month follow-up.

Conclusion  This is a safe, useful technique that facilitates location of intra-articular cyst pedicle, thus avoiding unnecessary damage in healthy tissues with no increased costs.

Synovial cysts (SCs) are the most prevalent wrist tumors, although most are asymptomatic, causing only cosmetic complaints. Although the treatment is predominantly conservative, patients with symptomatic lesions after the conservative approach or with cosmetic complaints may be candidates to surgical treatment. SCs may be treated by open surgery; nonetheless, either dorsal or palmar incisions pose greater risks of complications due to proximity of important neurotendinous structures, along with the possibility of adhesions and hypertrophic scarring. The arthroscopy has become an excellent option whenever the surgical treatment is indicated. ¹

SCs complete removal is not necessary, regardless the technique employed as a pedicle opening for content drainage has demonstrated to be all is needed. The arthroscopic technique comprises pedicle opening, SC drainage, and content overflow to the joint cavity. Therefore, pedicle location is essential for SC arthroscopic treatment. ²

In most patients, the SC originates from the radiocarpal joint; however, in up to 10% of patients, the pedicle may be located at the midcarpal joint (usually at the scaphotrapezial–trapezoid joint) or, seldom, could also be originated either from tendons or their sheaths. ³

The arthroscopic treatment for wrist SCs has been described by Osterman et al ³ for dorsal SCs in which most of the patients, the pedicle emerges from the scapholunate ligament dorsal portion (90%). Ho et al ⁴ have described that for volar SCs, the pedicle is usually located between the strong volar radiocarpal ligaments, particularly between the radioscaphocapitate ligament (RSCL) and the long radiolunate ligament (LRLL), the most frequent situation is between the LRLL and the short radiolunate ligament (SRLL) or radial and the RSCL.

Some techniques and tips have already been described to facilitate SC pedicle location during arthroscopy, and most were cited in an article that had been published by the authors with a series of patients. ⁵ We now employ a new, unprecedented technique for easier pedicle location during arthroscopy. The aim of this study is to demonstrate this new method in which we employ an 18-G needle to enhance SC pedicle location and drainage, along with the outcomes of a patient series ( Fig. 1 ).

Fig. 1.

Positioning for wrist arthroscopy. Schematic drawing of the optics as positioned on to 3/4 portal, in front of RSCL and LRLL interval (detail), along with the needle penetration through portal 1/2 (A) . Upper inner view of the joint with the optics at the 3/4 portal and the needle at the 1/2 portal draining the volar synovial cyst; the pedicle is located between the RSCL and the LRLL, the most frequent site of volar cysts (B) . LRLL, long radiolunate ligament; RSCL, radioscaphocapitate ligament.

Materials and Methods

We have employed SC needle drainage for the latest 16 patients who were operated: 9 had dorsal SCs and 7 had volar SCs. Minimal postoperative follow-up was 12 months with serial clinical evaluations in this period when functional, cosmetic, and pain assessments were made.

Surgical Technique and Results

The procedure follows the normal routine of wrist arthroscopy as follows: patient in supine position, brachial plexus regional block, pneumatic tourniquet application, traction mesh use, and 2.7-mm diameter optics use. Arthroscopic standard portals (1/2, 3/4, and 6R; radial and ulnar midcarpals) are employed, and the cyst's location is marked with a dermographic pen after positioning of the upper limb on the traction tower. ⁶

The surgeon should start the procedure with at least a good suspicion about the SC pedicle through previous clinical and imaging analysis. External SC compression maneuver, as described by Mathoulin and Gras, makes location easier inside the joint. At this point, we employ the 18-G needle to perform small punctures at the intervals between extrinsic carpal ligaments where the pedicle is suspected to remain. Whenever found, the SC is drained by a unique, puncture motion, overflowing the content toward the joint by pressure, which proves that the cyst's wall and pedicle have been ruptured. In case of failure to find the initially suspected site, other locations should be probed by proceeding with the most frequent intervals between extrinsic carpal ligaments ( Fig. 2 ).

Fig. 2.

Patient with a volar synovial cyst. Arthroscopic view with the optics positioned at the 3/4 portal and the needle entering through the 1/2 portal (A) . The interval between the RSCL and the LRLL is punctured, draining the cyst pedicle and cyst content is overflown toward inside the joint (B) . Procedure is completed with the resection of a portion of joint capsule with the shaver for a whole cyst drainage (C and D) . LRLL, long radiolunate ligament; RSCL, radioscaphocapitate ligament.

After pedicle location and initial drainage, the shaver is used to complete joint capsule and SC opening, so that a window remains open toward the joint's inner space to finish the procedure ( Fig. 3 ). Following capsule opening, SC overflow and content suction will provide complete disappearance of the tumoral mass. Abnormal synovial tissue is to be resected along with 4 to 6 mm of the volar capsule, forming a window-shaped defect. Again, external pressure on to the SC may aid in SC pedicle resection and complete drainage of its content ( Fig. 4 ).

Fig. 3.

Patient with a bulky, dorsal synovial cyst, showing its clinical appearance (A) and MRI imaging (B) . Positioning for wrist arthroscopy, with the optics at the ulnar midcarpal portal, and the needle at the radial midcarpal portal (C) . Clinical appearance of the synovial cyst treatment and resection (D) . MRI, magnetic resonance imaging.

Fig. 4.

Intra-articular view of the same patient from Fig. 3 . Optics positioned at the ulnar mid-carpal portal showing digit extrinsic extensor tendons and a dorsal synovial cyst (A and B) . Use of an 18-G needle for cyst drainage. Final and entire resection of the cyst at the completion of procedure (C and D) .

Portals are closed with 5–0 nylon sutures and the patient receives a short cast for up to 7 days postoperatively. Stitches are removed at 12 days after the procedure and the patients are followed-up for a period of 12 months.

In our series, all SCs were located at the suspected site as identified preoperatively and drained with this technique.

If the cyst could not be found and needled, the next step would be intracystic injection of methylene blue and standard arthroscopic resection can be followed by open resection if this maneuver has also been failed.

There was no significant change in results when compared with our earlier series. All patients have shown complete symptom improvement within 30 days, including SC's disappearance, with no severe complications or relapses during a 12-month follow-up.

Due to the addition of other methods (SC external location and preoperative magnetic resonance imaging (MRI) and SC external pressure for all patients), the pedicle was found in all patients within three puncture attempts. This fact probably reduces the chance of joint damage, enhancing patients' recovery.

Discussion

It is essential that the SC pedicle is encountered in the arthroscopic procedure. The problem arises as the SC pedicle is not always easily found, causing unnecessary damage to the joint capsule and ligaments due to multiple opening attempts with the shaver. Zaidenberg et al ² have proved such point, showing that fails and relapses of the SC arthroscopic treatment are caused by inadequate SC pedicle location inside the joint, as the cyst's external location almost always is not coincident with the articular origin. In addition, it is not uncommon for the patient to present two SCs separated by a few millimeters. For that reason, it is essential to precisely locate the pedicle preoperatively; the MRI is a very effective and noninvasive method. ²

Chung and Tay ⁷ have described that correct visualization of SC pedicle during arthroscopy varies from 9 to 100%, and its identification appears not to correlate with the risk of cyst relapse. ⁸ Edwards and Johansen ⁹ in a series of 45 patients with arthroscopically treated SC had found the pedicle in just 9% of the cases; a 2-year follow-up did not report any relapses. In opposition, Gallego and Mathoulin ¹⁰ in a same-subject study found the pedicle in all patients, with a further relapse rate of 12.3%. Despite the small size of our series, the use of a needle allowed correct identification of the pedicle in all patients, with no relapses in over 12 months. For that reason, we still believe that SC relapse may be the result of inadequate cyst pedicle opening.

Different techniques and tricks have been described to enhance SC pedicle location during arthroscopy. Rocchi et al ¹¹ claim that volar cysts originated from the radiocarpal joint are located proximal to the wrist flexion crease. Mathoulin and Gras ¹ on the other hand, have described the technique of external manual pressure onto the SC, so that a hypertrophic synovial tissue prominence is seen at the interval between radiocarpal ligaments through the arthroscopy, indicating the pedicle location. Yao and Trindade ¹² have described the use of direct methylene blue injection (Indigo Carmine, Akorn, Lake Forest, IL) inside the SC for pedicle location. This trick induces SC and pedicle blue staining, guiding the location during intra-articular viewing. In this procedure, 2 to 3 mL of methylene blue are injected inside the SC before the arthroscopy. The staining of the whole SC will deliver better intra-articular view.

Yamamoto et al ¹³ have described the use of ultrasonography (US) associated to arthroscopy for the treatment of SCs. According to these authors, the use of US facilitates viewing of the whole cyst, including the pedicle, blood vessels, nerves, and tendons. Even working gadgets as shavers may be identified and positioned using US.

It is important to emphasize that the cost of arthroscopic procedure must be considered when deciding for the operative technique. Pang et al ¹⁴ have compared the cost of the open procedure to arthroscopy for the resection of both dorsal or volar wrist SCs and found an average cost of $1.821 for the open approach and $3.668 for the arthroscopic procedure. Therefore, the technique presented here does not increase the value of the procedure, as a needle is a routinely employed material in the surgical context and has a very small cost as compared with the total amount of the procedure.

Nonetheless, the authors of this study stressed that the use of arthroscopy in small joints must be performed by qualified surgeons with adequate training. Furthermore, the needle has a cutting bezel that may cause important tissue injury if not properly used. Thus, we recommend that the surgeon should be capable to perform the classic shaver technique before using the above-described technique. ¹⁵

Conclusion

Arthroscopic treatment of wrist SC shows similar or better results as compared with the open technique in number of complications, shorter time for return to work, and cosmetic satisfaction. We describe an adaptation of the standard arthroscopic technique with the use of a needle to facilitate the pedicle location, which is essential for the adequate treatment of the pathology, and even sometimes as a tool for the ultimate treatment of the lesion by promoting cyst content drainage into the joint. The technique allows a precise, resolutive resection of the cyst by avoiding any additional damage to healthy tissues.

This method further reduces the chance of conversion to an open technique, thus decreasing possible complications such as hypertrophic scar, vascular and neurotendinous injury, or ligament instability. Besides, the presented technique does not increase the cost of the procedure, employing a simple and cheap material, easily found in any hospital environment. It is a useful technique that has been developed adding to the other methods and should be a part of the therapeutic armamentarium for those who perform the arthroscopic treatment of wrist SCs.