Patient Selection
From November 2017 to March 2020, a total of 11 continuous patients diagnosed as recurrent DWG were retrospectively reviewed. All patients underwent revision DWG cyst excision in an arthroscopic approach at the same center by the same surgeon. The recurrent DWG was defined as the reappearance of a DWG cyst from the radiocarpal or midcarpal joint at the same area as prior and was confirmed by both ultrasonography (US) and magnetic resonance imaging (MRI). The previous excision could be open or arthroscopically (Figure 1). Patients with other concomitant wrist pathology including fracture or ligamentous tear were excluded from the study. This study was approved by our Institutional Ethics Board and was complied with each participant’s consent.
Preoperative Evaluation
Ultrasonography
The wrist US examination was routine before the revision excision and was performed by an expert musculoskeletal sonographer. A GE LOGIQ E9 color Doppler ultrasound system (GE Medical Systems Ultrasound & Primary Care Diagnostics) was used. The criteria used to diagnose a ganglion cyst was a well-defined, anechoic or hypoechoic, unilocular or multilocular fluid collection not representing an anatomic bursa or joint recess, as described in the literature [12]. The largest diameter of the ganglion cyst was then measured (Figure 1).
Magnetic Resonance Imaging
All patients underwent MRI examinations routinely before the revision excision. MRI was performed in a 3.0-T superconducting magnet (Sigma; GE Medical Systems) with a standardized institutional protocol. The MRI protocols included coronal, sagittal, and axial sequences. Each sequence included the T1- and T2-weighted phases. MRI scans were firstly evaluated by an expert musculoskeletal radiologist, and a ganglion cyst was defined as a focal lesion in the soft tissue with signal isointense to fluid [13]. The location and limits of the cyst were then evaluated on T2-weighted axial and sagittal planes by the surgeon. It should be noted that the cyst was probably multilocular due to the local scaring in patients undergoing previous excision [9, 10], therefore the limits of the cyst and the location of extensor tendons should be identified carefully on MRI scans (Figure 2).
Surgical Technique
The surgery was performed under ultrasound-guided axillary block anesthesia, and a pneumatic tourniquet was used with 260 mmHg of pressure to allow a good view on arthroscopy.
All patients underwent wrist arthroscopy in a supine position, with the arm fixed to the table and the elbow flexed to 90° with the wrist in a vertical distraction of 10-15 lbs using a traction tower. A 2.5-mm arthroscope of a visual angle of 30° (ConMed Linvatec) was used, and the normal saline solution was provided through the arthroscopic cannula.
An arthroscopic inspection was performed through the midcarpal ulnar (MCU) portal with the arthroscope, systematically evaluating the wrist following a sequence from radial to ulnar, distal to proximal, and volar to dorsal so as not to miss any concomitant pathology (Figure 3). The dorsal capsule in the region of the scapholunate interosseous ligament was carefully checked and a ganglion stalk was often identified, which usually appeared transparent, gray, or opalescent. Sometimes a real stalk was not present and an external pressure applied over the mass was helpful to localize the ganglion base.
Once the stalk was visualized, a needle was introduced through the ganglion into the midcarpal joint from the midcarpal radial (MCR) portal (Figure 4). A direct transcystic MCR approach was created and a 2.9-mm shaver (ConMed Linvatec) was introduced through the ganglion into the joint. Based on the location and limits of the cyst on preoperative MRI, the ganglion stalk and adjacent pathological dorsal capsule were excised under arthroscopic vision, until the extensor carpi radialis brevis (ECRB) and extensor digitorum communis (EDC) of the index finger were exposed (Figure 5). The extrusion of gelatinous material was usually the evidence of a successful decompression of the cyst. Because of thick scarring after previous surgery, clear visualization of the inner wall of a recurrent cyst could be difficult, and the ganglion could be multilocular. Percutaneous squeezes of the ganglion in multiple directions could help to locate limits of the cyst, then a complete excision of the ganglion wall and stalk proceeded. Great caution should be taken to prevent injuries to ECRB and EDC tendons while ganglion excision was under external pressure. After the ganglionectomy was completed, the disappearance of the ganglion should be confirmed arthroscopically, followed by palpation of the dorsal wrist to reconfirm after the arthroscope was removed. The portals were closed with nylon sutures.
A bulky dressing was applied immediately after the procedure and no plaster or brace was utilized. Patients were encouraged to gently use their hands as tolerated, avoiding strenuous work and weight lifting for 4 weeks. Physical therapy was recommended to all patients.
Data Collection
Demographic Data and Medical History
A questionnaire was used to record the age, gender, dominant side, affected side, prior surgical approach, and time of recurrence. The time of recurrence was documented by the patient recall and determined by the interval between primary excision and the first reappearance of the cyst.
Pain and Function Evaluation
Pain during activity was evaluated using the visual analog scale (VAS) of 0 (no pain) to 10 (worst pain ever felt), and the residual pain was recorded if VAS score >0 at the final follow-up. Active range of motion (ROM) of the wrist in flexion and extension in degrees was measured with a goniometer, and the hand grip strength in kilograms was measured using a digital dynamometer. The above evaluations were performed before surgery and at the final visit. Postoperative evaluations were performed at a minimum of 24 months.
Second Recurrence
After revision arthroscopic excision, a second recurrence was defined as a reappearance of the mass at the same site, with a positive transillumination test [9]. Time of the second recurrence was recorded based on the patient’s first observation instead of the surgeon’s confirmation. At the final visit, all patients were asked to receive a wrist US to confirm the recurrence or not.
Statistical Analysis
Statistical analyses were performed using SPSS 25.0 software package (SPSS Inc., IBM, USA). Descriptive statistics were conducted for all variables. Continuous variables (age, time of recurrence, largest cyst diameter, length of follow-up, VAS score, active ROM, hand grip strength, and time of the second recurrence) were reported as mean ± standard deviation (SD), and the comparative analysis between the pre- and post-operation was performed by Student t test or Mann-Whitney U test according to the assumption of normality and homoscedasticity. Categorical variables (gender, dominant side, affected side, prior surgical approach, and residual pain) were reported as numbers (percentage). Statistical significance was set at P<0.05 for all analyses.