Rationale and Basic Science

Dorsal wrist ganglions are the most common type of soft–tissue swellings that present around the wrist. They usually originate from the dorsal portion of the scapholunate ligament, at or just distal to the dorsal folds of the radiocarpal capsule.¹ The dorsal wrist ganglion originates from the scapholunate joint. The cyst pedicle lies at the junction of the dorsal capsule and the distal–most part of the dorsal scapholunate interosseous ligament. From here, the ganglion swells into a sac lying along the dorsal capsule—from where it protrudes as a clinically obvious swelling. The intracapsular portion of the ganglion overlies the scapholunate joint, but the large extra–articular fundus of the cyst may vary in location (although it still remains in close vicinity of the joint).

The swelling is benign but can be painful, and surgical excision by an open procedure is recognized as the most effective method of treatment of this condition. Unfortunately, recurrence is possible even after open surgery and is likely related to removal of the externally visible cyst without addressing the intra–articular pedicle. Management of the “occult” ganglion that remains intracapsular and is not clinically visible provides an even further treatment challenge. As the swelling cannot be seen outside the wrist joint, open surgery consists of an almost empirical excision of a 1.5–cm diameter of dorsal wrist capsule overlying the scapholunate joint.

Wrist arthroscopy offers an excellent view of the wrist joint, and with modern mechanized shavers intra–articular pathology can be effectively debrided. In the case of a ganglion, the intra–articular portion is easy to see because it lies against the dorsal capsule. The pedicle of the ganglion at the scapholunate ligament can be visualized in the majority of cases, and can be resected effectively along with the intra–articular portion with minimal surgical incisions. This may reduce the incidence of recurrence after surgery. In addition, arthroscopy allows a thorough visual examination and palpation by probe of the radiocarpal and midcarpal joints to exclude other sources of wrist pain. The use of wrist arthroscopy to effectively treat dorsal wrist ganglia is not new and was first proposed by Osterman in 1995.²

The “occult” ganglion is entirely intracapsular and cannot the visualized during open surgery. Arthroscopy, however, allows visualization and resection of the entire ganglion. In the author’s opinion, arthroscopy is the treatment of choice for an occult ganglion.

Routine wrist arthroscopy commences with joint inspection through the 3–4 radiocarpal portal. The ganglion overlies this portal and the intra–articular portion of the ganglion obscures visualization. If arthroscopic ganglionectomy is planned, the 6–R portal is used to gain initial entry to the wrist joint. When the scope is directed to the radial side, it is possible to obtain a tangential view of the ganglion adherent to the wrist capsule on one side and the scapholunate joint on the other. A shaver introduced through the 3–4 portal enters the joint through the ganglion. The perforated ganglion is then resected by running the shaver along the surface of the capsule.

Clinical Features and Indications

Most ganglia present in females in the second, third, or fourth decades of life. Spontaneous resolution is common but can take several years, with 50% of untreated patients “ganglion free” when assessed at six years.³

The most common presenting complaint is the cosmetic concern relating to a lump present on the back of the wrist. The other less common complaints are discomfort localized to the area of the swelling or fear of possible malignancy. Although the diagnosis is usually quite obvious in the majority of cases, other causes of wrist pain must be excluded by a thorough clinical examination and routine radiography. The ganglion is a soft cystic swelling that has no inflammatory signs. Transillumination by a penlight and fluctuation are two key clinical signs that demonstrate the clear fluid nature of the lump and exclude other soft–tissue tumors. If the patient seeks absolute confirmation, ultrasound examination is diagnostic. MR imaging is more expensive, but is indicated if Kienbock’s disease is to be excluded.

The patient with an occult wrist ganglion will complain of wrist discomfort over the area of the scapholunate joint and may or may not notice intermittent swelling in the area. As the swelling is not visible clinically, confirmation by MR imaging or ultrasound is mandatory. Ultrasound is the most cost effective and will demonstrate the ganglion as a hypoechoic mass overlying the scapholunate joint and deep to the wrist capsule (Figure 21.1).⁴

FIGURE 21.1 Ultrasound appearance of an occult ganglion on an axial view of the wrist. The 5-mm × 3-mm ganglion (marked by crosshairs) is seen overlying the interosseous ligament between the scaphoid (S) and the lunate (L).

Management options include reassurance that the swelling is harmless, and spontaneous resolution is possible if one is prepared to wait for a reasonable length of time. This holds true especially in the pediatric population, where cysts around the wrist are likely to resolve spontaneously in up to 80% of cases.⁵ A brief period of rest in a splint may help to reduce pain. Needle aspiration does provide immediate symptom relief, with resolution of the swelling, but the reported recurrence rate is about 60%.^6,7 The injection of steroid after aspiration does not seem to affect the high recurrence rates, and with risk of subcutaneous atrophy and skin depigmentation is not routinely recommended.⁸

Surgery is indicated if there is failure to respond to conservative treatment or if the patient declines injection. Open surgical excision has long been considered the definitive treatment of choice, but even surgery cannot prevent the risk of recurrence that can occur in as many as 25% of cases. Open surgical excision also has complications of scar tenderness or hypertrophy, keloid formation, and stiffness if prolonged postoperative immobilization is used.

Arthroscopic excision may be undertaken if the surgeon is familiar with arthroscopic techniques in the wrist. The patient who desires surgery must understand that surgery is one of the better options but spontaneous resolution is possible. The swelling itself is harmless. Pain arising from the wrist itself due to other pathology will not improve after ganglion excision. Patients who wish to have the swelling removed for cosmetic reasons must be informed that scar formation, even after arthroscopy, can be noticeable.

Contraindications

Surgical Technique

The technique for arthroscopic ganglionectomy includes the standard wrist arthroscopy instrumentation and setup. The upper extremity is prepped and draped and an exsanguinating tourniquet is applied. Finger traps are applied to the index and long fingers and the hand and wrist are placed in a distraction tower with 10 to 15 pounds of traction. The arm must be secured firmly to the table with sterile straps in order to provide countertraction. The 3–4 and 6–R portals are identified and the tourniquet is inflated. The ganglion is marked out because it may become less apparent during the surgical procedure.

Whereas it is routine to inflate the joint with saline prior to insertion of the arthroscope, in this procedure saline insufflation is avoided initially to allow identification of the ganglion and its stalk. A 1.9– or 2.7–mm arthroscope is used according to the size of the wrist.

Contrary to traditional wrist arthroscopy that commences on the radial side with initial visualization through the 3–4 portal, for ganglionectomy the author prefers to start from the ulnar side of the wrist from the 6–R portal for the following reasons. Introduction of the scope through the 3–4 portal may actually enter through the ganglion, causing it to rupture and making it less distinct. The intra–articular portion of the ganglion impairs visibility and examination of the joint is not possible. Furthermore, the 3–4 portal will be used for instrumentation to debride the ganglion. The author therefore recommends using the 3–4 portal for diagnostic arthroscopy only after the ganglion has been debrided.

An 18–gauge needle is inserted into the 6–R portal first to localize the level of the ulnocarpal articulation and to ensure that the triangular fibrocartilagenous disc is not violated. A 4–mm transverse incision is made in the skin and a small hemostat is introduced into the joint and spread gently. The blunt trocar and cannula are inserted and then the trocar is exchanged for the scope (Figure 21.2).

FIGURE 21.2 With the right arm suspended in traction, the arthroscope has been introduced from the 6-R portal. The ganglion has been marked and is seen to overlie the 3-4 portal.

By directing the scope radially, it is possible to see the scapholunate articulation in profile. The ganglion can be seen lying against the dorsal capsule. Tracking the ganglion as the scope is tilted dorsally, the stalk of the ganglion can be seen running to the distal part of the dorsal scapholunate interosseous ligament along the capsular reflection. When the inflow of saline is commenced, the ganglion is compressed against the dorsal capsule and becomes less distinct (Figure 21.3). Fluid outflow may be provided by an 18–gauge needle inserted into the 1–2 portal. This, however, is not always necessary because adequate outflow will be provided during insertion of the shaver.

FIGURE 21.3 Arthroscopic view from the 6-R portal. The ganglion (*) is seen to the left, overlying the dorsal wrist capsule. The lunate, in profile, is seen to the right. The ganglion comes into contact with the lunate at the level of the dorsal part of the scapholunate interosseous ligament.

An 18–gauge needle is introduced through the ganglion and into the 3–4 arthroscopic portal. As landmarks may be obscured by the swelling, the portal is made in line with the radial border of the long finger. The needle is inserted into the joint under arthroscopic vision and is directed into the radiocarpal space (Figure 21.4).

FIGURE 21.4 Arthroscopic view of the right wrist from the 6-R portal after a needle is inserted through the 3-4 portal (left). The needle has perforated the ganglion (*), which appears more flattened due to saline inflow through the joint. The scaphoid (S) and lunate (L) are seen in profile.

The 3–4 portal is then developed by making a transverse incision through the skin and spreading the capsular entry with a small hemostat. A 2.3–mm full–radius shaver is introduced into the joint and the ganglion is then systematically resected, starting with the capsular portion (Figure 21.5).

FIGURE 21.5 A 2.5-mm shaver is introduced through the 3-4 portal (left). When viewed from the 6-R portal, the scope enters the joint through the base of the ganglion itself (right).

Resection requires working at a very steep angle, with the shaver at times almost parallel to the forearm as the surgeon resects the capsular portion of the ganglion. An aggressive shaver may be used for this purpose. The use of the 1–2 portal has been recommended for better visualization and ease of resection.^9,10 In the author’s experience, however, this has not been necessary. The author recommends avoiding this portal because of the risk of radial sensory nerve complications.

Attention is then turned to the pedicle that runs along the distal capsular reflection to the distal–most part of the dorsal SLIL. Using a nonaggressive shaver angled distally, the pedicle is debrided with gentle pressure against the SLIL. Caution must be exercised when using an aggressive shaver for this purpose because it may disrupt part of the ligament (Figure 21.6).

FIGURE 21.6 After debriding the capsular portion of the ganglion, the shaver is angled distally to the pedicle at the reflection of the dorsal capsule from the scapholunate joint.

Some patients may demonstrate additional synovitis along the rim of the dorsal radius. This may be a manifestation of underlying scapholunate instability and needs to be evaluated with a midcarpal arthroscopy.¹¹ The red fragile fronds of synovitis are distinct from the well–localized and avascular ganglion. The synovitis can also be debrided using a shaver, or lesser amounts can be vaporized using a thermal probe. By this time, the intra–articular ganglion is completely debrided, there is a visible defect in the dorsal capsule, and the extra–articular portion of the ganglion should have been decompressed (Figure 21.7).

FIGURE 21.7 Arthroscopic view from the 6-R portal after completion of ganglion excision.

If the external ganglion mass is still tense, the capsular window needs to be widened to allow the ganglion to discharge into the joint. Using an arthroscopic punch forceps, the portal hole in the capsule is widened. This may help to minimize possibilities of recurrence by removal of the one–way “capsular valve” that allows fluid to accumulate in the extra–articular portion of the ganglion.¹² Capsular window enlargement is not necessary for the treatment of occult ganglia that are totally intra–articular. Some authors recommend capsular resection only for cases when the ganglion or its stalk is not identifiable through the arthroscope. The author prefers to enlarge the opening using controlled removal of small portions with a forceps, rather than an aggressive shaver, because this method has less risk of injury to the radial wrist extensor tendons (Figure 21.8).

FIGURE 21.8 View from the 6-R portal. Widening of the capsular portal brings the wrist extensor tendon (E) into view.

Once resection is complete, further examination of the radiocarpal joint is performed by inserting the arthroscope through the 3–4 portal. The appearance of articular surfaces is recorded and the integrity of the scapholunate ligament and the triangular fibrocartilage is confirmed with a probe.

Arthroscopic evaluation of the midcarpal joint is essential after resection of the ganglion. It is not uncommon to visualize a minor degree of scapholunate laxity with a step–off at the articulation. Less commonly, the ganglion extends into the midcarpal joint—obscuring visualization through the radial midcarpal portal. An ulnar midcarpal portal is then developed for the scope, and the ganglion is debrided with a shaver introduced through the radial midcarpal portal (Figure 21.9).

FIGURE 21.9 View of the midcarpal joint through the radial midcarpal portal, showing the scaphoid (S), lunate (L), and capitate (C). There is increased flexion of the scaphoid visible as a step-off at the scapholunate joint.

Upon completion, the scope is removed and the tourniquet is deflated. The skin edges of the portals are approximated with Steri–Strips. Postoperatively, the patient is splinted for comfort for a brief period of four to seven days. Active wrist motion is encouraged after this period of time, and the patient is allowed activities of daily living. Heavy lifting or strenuous work is not encouraged for the first six weeks.

Results

While providing the obvious result of removal of the soft–tissue mass, the additional benefits of arthroscopic ganglionectomy include improved pain scores and grip strength and an increase in wrist dorsiflexion. In the author’s personal series, he reviewed 15 patients with occult dorsal wrist ganglia treated with arthroscopic resection with a mean follow–up of 18 months. All patients had tenderness over the scapholunate joint without clinically obvious swelling. The diagnosis was made by ultrasound or MRI in all cases. Although there was no radiographic evidence of carpal instability, six patients had clinical evidence of scapholunate instability. Twelve patients remained pain free at final follow–up, and three patients subsequently underwent dorsal capsulodesis for persistent scapholunate instability. Each of these patients did not show any recurrence of the ganglion on ultrasound scans.

The most common concern after surgery for ganglion removal is recurrence, with reported rates from less than 1 to 25% after open surgery. Recurrence rates after arthroscopic ganglionectomy appear to be much lower. Osterman² did not report any recurrences in 18 cases, whereas Fontes¹³ reported recurrence in 1 of 32 cases, Luchetti in 2 of 34 cases, and Rizzo in 2 of 42 cases.^2,14,15 To prevent recurrence, it is essential to identify and effectively debride the pedicle. If the pedicle is not clearly visualized in the radiocarpal joint, the midcarpal joint must also be examined. A 1–cm section of dorsal capsular cuff must be resected if the pedicle is not well visualized or if the external ganglion remains tense even after the intra–articular portion is debrided.

Other complications (such as neuroma formation and scar hypertrophy) can occur with arthroscopic surgery (as they can with open surgery). Neuroma formation can be minimized by avoiding use of the 1–2 and 6–U portals and by developing portals by blunt dissection to the capsule after incising only the skin with a knife. Transverse skin incisions instead of the traditional longitudinal skin stabs for making portals may help minimize scar hypertrophy and keloid formation.

The author routinely recommends scar massage and silicone patch taping at night to minimize scar hypertrophy after all surgical procedures on the hand and wrist. Wrist stiffness is common after open ganglion surgery if the joint is immobilized after surgery. Arthroscopy has the advantage of smaller incisions with minimal soft–tissue dissection, allowing early postoperative rehabilitation. To avoid postoperative stiffness, joint mobilization is commenced as soon as three to four days after surgery (when the postoperative pain has settled).

Summary

Arthroscopic ganglionectomy offers a viable treatment option for management of dorsal wrist ganglia after nonoperative treatment fails to resolve symptoms. The procedure can be undertaken by any surgeon familiar with arthroscopic wrist surgery using standard wrist portals and instrumentation. Correct use of the 3–4 and 6–R portals is necessary to facilitate debridement. Longer–term studies are needed to demonstrate improved results over open surgery, but intuitively arthroscopic excision seems to be the preferred option because of the smaller scars, earlier rehabilitation, and lower recurrence rates.