Thermal capsular shrinkage in the throwing athlete

Radiofrequency technology for shoulder instability was rapidly adopted despite limited clinical evidence and a poor understanding of its indications. Reports of serious adverse events followed, leading to its abandonment. This paper presents findings from a multicenter randomized clinical trial evaluating the safety and efficacy of electrothermal arthroscopic capsulorrhaphy (ETAC) compared with open inferior capsular shift (ICS) and reviews the role of randomized trials in adopting new technology.

Patients (>14 years) diagnosed with multidirectional instability or multidirectional laxity with anteroinferior instability and failed nonoperative treatment were enrolled. Patients with bone lesions or labral, biceps anchor, or full-thickness rotator cuff tears were excluded intraoperatively. Outcomes included Western Ontario Shoulder Instability Index, function and recurrent instability at 2 years postoperatively, and surgical times.

Fifty-four subjects (mean age, 23 years; 37 women) were randomized to ETAC (n = 28) or open ICS (n = 26). The groups were comparable at baseline, except for external rotation at the side. At 2 years postoperatively, there were no statistically or clinically significant differences between groups for the Western Ontario Shoulder Instability Index (P = .71), American Shoulder and Elbow Surgeons score (P = .43), Constant score (P = .43), and active range of motion. Recurrent instability was not statistically different (ETAC, 2; open, 4; P = .41). ETAC (23 minutes) was significantly shorter than open ICS (59 minutes) (P < .01) surgery. Three subjects (1 ETAC, 2 open) had stiff shoulders.

At 2 years postoperatively, quality of life and functional outcomes between groups were not clinically different. ETAC had fewer complications and episodes of recurrence compared with open surgery. This evidence reinforces the need to critically evaluate new technology before widespread clinical use.

Cadaveric shoulders underwent thermal capsulorrhaphy and subacromial decompression with 3 different commercially available radiofrequency (RF) devices to evaluate local and regional fluid temperatures while arthroscopic procedures were being performed. Fifteen completely thawed fresh-frozen shoulders underwent both thermal capsulorrhaphy and subacromial decompression. During thermal capsulorrhaphy, Fluoroptic mini-thermometer probes (Luxtron model 3000) were placed in the inflow bag; in the glenohumeral joint, near the inferior glenohumeral ligament; and on the RF wand. During subacromial decompression, the temperature probes were placed in the anterior and posterior subacromial space, as well as in the inflow bag and on the RF wand. All data were initially analyzed by use of analysis of variance, followed by pairwise comparison, adjusted for multiple testing by use of the Scheffé method. Mean fluid temperatures (in degrees Celsius [± SD]) were highest at the RF wand during both capsulorrhaphy and subacromial decompression. Mean fluid temperatures were much lower at other recorded sites. In this model, we show no deleterious elevation in arthroscopic fluid temperature while performing thermal capsulorrhaphy or subacromial decompression using any of the 3 devices at their recommended settings.

Purpose: To determine joint fluid temperatures at different time intervals during treatment with radiofrequency energy (RFE) applied in intermittent and continuous treatment manners under flow or no-flow conditions using a simulated shoulder joint model. Type of Study: In vitro measurement of simulated joint fluid temperature during RFE treatment. Methods: A custom-built jig with a chamber (volume size, 25 mL) was used to mimic the adult human shoulder. Three RFE systems: Vulcan EAS plus TAC-S probe (Smith & Nephew Endoscopy, Andover, MA); VAPR II plus End-Effect Electrode (Mitek, Westwood, MA); and ArthroCare 2000 plus TurboVac 90° probe (ArthroCare, Sunnyvale, CA) were tested in the chamber with saline solution initially set at 23°C. Each RFE probe was applied in a paintbrush pattern on the capsular tissue in the chamber and a fluoroptic thermometry probe was placed 1 cm above the RFE treatment probe to record the fluid temperature. Both intermittent and the continuous treatment manners were tested under flow and no-flow conditions. For each probe/manner/flow combination, 6 bovine capsular tissue specimens were tested (n = 6). All data were recorded using a HyperTerminal software program (Hilgraeve Inc, Monroe, MI) into a personal computer. Results: When using intermittent and continuous treatment manners with flow, all recorded chamber fluid temperatures for all tested RFE probes at each time interval were below 40°C. Under no-flow conditions, with intermittent treatment, the ArthroCare probe caused joint fluid temperatures to exceed 50°C after 70 seconds of RFE treatment. With the continuous treatment, the ArthroCare caused chamber fluid temperatures to exceed 65°C after 2 minutes of treatment. The highest mean recorded chamber fluid temperature was caused by ArthroCare probe, which reached 80°C at 3 minutes. For all probes, continuous treatment caused significantly higher chamber fluid temperatures than intermittent treatment. Conclusions: The results of this study indicate that using flow during thermal capsulorrhaphy could lower joint fluid temperature to prevent heated joint fluid from killing chondrocytes of articular cartilage, and the intermittent treatment manner caused lower fluid temperature compared with continuous treatment within the RFE-treated shoulder joint. Clinical Relevance: Articular cartilage of the humeral head may suffer potential thermal injury from heating of joint fluid during RFE thermal capsulorrhaphy.