The Role of Flexible Radiofrequency Energy Probes in Hip Arthroscopy

Radiofrequency in arthroscopic shoulder surgery: a systematic review

BACKGROUND

Radiofrequency has seen an increase in use in orthopedics including cartilage lesion debridement in the hip and knee as well as many applications in arthroscopic shoulder surgery. The purpose of this systematic review is to evaluate the safety and usage of radiofrequency in the shoulder.

METHODS

This systematic review was registered with PROSPERO (international registry) and followed the preferred reporting items for systematic review and meta-analysis protocols (PRISMA-P) guidelines. Embase and PubMed were searched using: "shoulder," "rotator cuff," "biceps," "acromion" AND "monopolar," "bipolar," "ablation," "coblation," and "radiofrequency ablation." The title and abstract review were performed independently. Any discrepancies were addressed through open discussion.

RESULTS

A total of 63 studies were included. Radiofrequency is currently utilized in impingement syndrome, fracture fixation, instability, nerve injury, adhesive capsulitis, postoperative stiffness, and rotator cuff disease. Adverse events, namely superficial burns, are limited to case reports and case series, with higher-level evidence demonstrating safe use when used below the temperature threshold. Bipolar radiofrequency may decrease operative time and decrease the cost per case.

CONCLUSIONS

Shoulder radiofrequency has a wide scope of application in various shoulder pathologies. Shoulder radiofrequency is safe; however, requires practitioners to be cognizant of the potential for thermal burn injuries. Bipolar radiofrequency may represent a more efficacious and economic treatment modality. Safety precautions have been executed by institutions to cut down patient complications from shoulder radiofrequency. Future research is required to determine what measures can be taken to further minimize the risk of thermal burns.

Biomechanical Assessment of Hip Capsular Repair and Reconstruction Procedures Using a 6 Degrees of Freedom Robotic System

BACKGROUND

Although acetabular labral repair has been biomechanically validated to improve stability, capsular management of the hip remains a topic of growing interest and controversy.

PURPOSE

To biomechanically evaluate the effects of several arthroscopically relevant conditions of the capsule through a robotic, sequential sectioning study.

STUDY DESIGN

Controlled laboratory study.

METHODS

Ten human cadaveric unilateral hip specimens (mean age, 51.3 years [range, 38-65 years]) from full pelvises were used to test range of motion (ROM) for the intact capsule and for multiple capsular conditions including portal incisions, interportal capsulotomy, interportal capsulotomy repair, T-capsulotomy, T-capsulotomy repair, a large capsular defect, and capsular reconstruction. Hips were biomechanically tested using a 6 degrees of freedom robotic system to assess ROM with applied 5-N·m internal, external, abduction, and adduction rotation torques throughout hip flexion and extension.

RESULTS

All capsulotomy procedures (portals, interportal capsulotomy, and T-capsulotomy) created increases in external, internal, adduction, and abduction rotations compared with the intact state throughout the full tested ROM (-10° to 90° of flexion). Reconstruction significantly reduced rotation compared with the large capsular defect state for external rotation at 15° (difference, 1.4°) and 90° (difference, 1.3°) of flexion; internal rotation at -10° (difference, 0.4°), 60° (difference, 0.9°), and 90° (difference, 1.4°) of flexion; abduction rotation at -10° (difference, 0.5°), 15° (difference, 1.1°), 30° (difference, 1.2°), 60° (difference, 0.9°), and 90° (difference, 1.0°) of flexion; and adduction rotation at 0° (difference, 0.7°), 15° (difference, 0.8°), 30° (difference, 0.3°), and 90° (difference, 0.6°) of flexion. Repair of T-capsulotomy resulted in significant reductions in rotation compared with the T-capsulotomy condition for abduction rotation at -10° (difference, 0.3°), 15° (difference, 0.9°), 30° (difference, 1.3°), 60° (difference, 1.7°), and 90° (difference, 1.5°) of flexion and for internal rotation at -10° (difference, 0.9°), 60° (difference, 1.5°), and 90° (difference, 2.6°) of flexion. Similarly, repair of interportal capsulotomy resulted in significant reductions in abduction (difference, 0.9°) and internal (difference, 1.4°) rotations compared with interportal capsulotomy at 90° of flexion. In most cases, however, after the repair procedures, ROM was still increased in comparison with the intact state.

CONCLUSION

The results of this study suggest that common hip arthroscopic capsulotomy procedures can result in increases in external, internal, abduction, and adduction rotations throughout a full range (-10° to 90°) of hip flexion. However, capsular repair and reconstruction succeeded in partially reducing the increased rotational ROM caused by common capsulotomy procedures. Thus, consideration should be allotted toward capsular repair or reconstruction in cases with an increased risk of residual instability.

CLINICAL RELEVANCE

Although complete restoration of joint stability may not be fully achieved at time zero, capsular repair and reconstruction may lead to improved patient outcomes by bringing hip rotational movements nearer to normal values in the immediate postoperative period, especially in cases in which extensive capsulotomy is performed.

What are the current indications for use of radiofrequency devices in hip arthroscopy? A systematic review

The role of radiofrequency energy (RFE) devices has been minimally studied in hip arthroscopy. The purpose of this study was to determine the role of RFE devices in hip arthroscopy through a systematic review of the literature. We searched the PubMed database using the following Medical Subject Heading terms: hip arthroscopy, hip radiofrequency, thermal capsulorrhaphy, thermal chondroplasty and radiofrequency debridement. Two authors independently reviewed the literature and included articles based on predetermined inclusion criteria. We excluded review, technique and experimental articles. After title and abstract review, we selected 293 articles for full-text review. Ten articles met the inclusion and exclusion criteria. For the included articles, a total of 305 hips underwent arthroscopy with concomitant RFE treatment at a mean age of 25.7 years. Eight articles presented patient-reported outcome (PRO) instruments, one study did not report an outcome instrument but utilized an evaluation of postoperative range of motion (ROM) and 1 year magnetic resonance image (MRI) and computed tomography (CT) imaging. The remaining article measured only the ROM pre- and postoperatively. Only one of the articles reviewed reported complications. Current evidence on the safety and indications for use of RFE devices in hip arthroscopy is insufficient. The literature shows mixed results regarding its use in hip arthroscopy. Although the use of thermal energy is not without risk, if used judiciously and appropriate precautions are taken to avoid damage to adjacent tissues, those devices can be useful for the treatment of certain intra-articular hip pathologies arthroscopically.

Ligamentum teres injuries of the hip: a systematic review examining surgical indications, treatment options, and outcomes

PURPOSE

Hip arthroscopy is becoming a common technique for the diagnosis and treatment of ligamentum teres pathologic conditions. This systematic review aims to determine the indications/contraindications, treatments, and surgical outcomes for management of ligamentum teres injuries.

METHODS

We searched EMBASE, MEDLINE, and PubMed databases from 1946 to November 28, 2013 for all relevant English articles pertaining to surgical treatment of the ligamentum teres. A hand search of the reference sections of included articles was performed, and all relevant articles were systematically screened in duplicate, with agreement and descriptive statistics presented.

RESULTS

We identified 1,016 studies, 9 of which (4 case series and 5 case reports) met our eligibility criteria. These studies had a total of 87 patients (89 hips) who had undergone either arthroscopic debridement (81 patients, 83 hips) or reconstruction with autografting, allografting, or synthetic grafting (6 patients) of a torn ligamentum teres. Major qualifications for surgery included persistent hip pain despite conservative treatment and mechanical symptoms or instability symptoms (e.g., clicking or locking). Advanced arthritis (i.e., radiographic joint space < 2 mm) was the only reported contraindication. Patients were followed postoperatively for 1.5 to 60 months and were assessed using subjective methods (i.e., modified Harris Hip Score [mHHS] and Non-Arthritic Hip Score [NAHS]). Overall, both debridement and reconstruction improved the condition of patients, with a 40% increase in reported postoperative functional scores as well as a reported 89% of patients who were able to return to regular activity/sport.

CONCLUSIONS

Ligamentum teres debridement is indicated for short-term relief of hip pain caused by partial-thickness tears (type 2) failing conservative management, whereas reconstruction with autografts, allografts, or synthetic grafts may be indicated for type 1 (full-thickness) ligamentum teres tears that are deemed "reparable," cause instability, have failed previous debridement, or a combination of these conditions.

LEVEL OF EVIDENCE

Level IV, systematic review of Level IV and Level V studies.

Implicit Active Constraints for Robot-Assisted Arthroscopy

This paper presents an Implicit Active Constraints control framework for robot-assisted minimally invasive surgery. It extends on current frameworks by prescribing the external constraints implicitly from the operator motion, forgoing the need for pre-operative imaging; the constraints are defined in situ so as to avoid the use of invasive fiducial markers. A hands-on cooperatively-controlled robotic platform, comprising of a surgical instrument and a compliant manipulator, has been designed for an arthroscopic procedure. The surgical platform is capable of constraining the pose of the instrument so as to ensure it passes through the incision point and does not cause trauma to the surrounding tissue. A flexible arthroscopic instrument is designed and its use is investigated to enlarge reachable and dexterous workspace, increasing the accessibility to the target anatomy. The behaviour of the flexible instrument is analysed. A detailed performance analysis is conducted on a group of subjects for validating the control framework, simulating a minimally invasive arthroscopic procedure. Results demonstrate a statistically significant enhancement in the control ergonomics as well as the accuracy and safety of the procedure.

Effect of radiofrequency use on hip arthroscopy irrigation fluid temperature

PURPOSE

The purpose of this study was to determine operating parameters for joint fluid lavage using radiofrequency (RF) in maintaining intra-articular temperatures ≤50°C in the hip joint and to then quantify the influence of flow rate on maintaining safe intra-articular temperatures.

METHODS

Fiberoptic intra-articular thermometers at radial distance intervals of 1, 2, 5, and 10 mm, spanning cross-sectional areas of 3.14, 12.56, 78.5, and 314.1 mm(2), respectively, from the RF probe were used in 3 human hip cadaveric specimens at room temperature, with 9 trials per variable, using a 3-portal technique with a capsule release. Using a new Dyonics RF System continuously at the superior capsulolabral junction for 90 seconds, continuous temperatures were recorded at 50 mm Hg inflow and variable outflow intervals: no flow and 5, 15, and 30 seconds. Lavages were 1 second in duration on suction. Statistical comparison was through multivariate regression analysis and a logistic model.

RESULTS

Temperatures reached ≥50°C at 5-mm radial distance from the probe in all but the 5-second pulse lavage group. Elevated temperatures were reached within 1 to 2 seconds locally (1- to 2-mm radial distance) and at a radial distance of 5 mm in the 15-, 30-, and 0-second lavage groups. Logistic regression revealed a reduction in the odds that temperatures ≥50°C will occur as flow frequency increases every 30 (odds ratio = 0.68, P = .086); 15 (odds ratio = -1.22, P = .0067); and 5 (odds ratio = -4.26, P < .0001) seconds.

CONCLUSIONS

Increasing-interval pulsed irrigation is effective in maintaining intra-articular temperature profiles below 50°C during use of continuous RF ablation. Five-second-interval pulsed lavage is the longest flow interval identified during which fluid 5 mm radially from the RF device never reached temperatures >50°C.

CLINICAL RELEVANCE

Clinical guidelines for using the RF ablation include: meticulous technique, intermittent use, good inflow and outflow, and pulsed lavage at frequent intervals.

Use of a hip arthroscopy flexible radiofrequency device for capsular release in frozen shoulder

Adhesive capsulitis is a common and challenging condition to treat. Arthroscopic capsular release is usually contemplated when conservative treatment fails or when there is severe and/or chronic loss of range of motion. This procedure can be difficult to perform because of difficult access to the joint, poor visualization, and loss of working space from retraction of the joint capsule. The articular surfaces and the axillary nerve are also at higher risk of injury. Arthroscopic scissors, shavers, and electrocautery are typically used to perform the capsular release. To perform a safer and more precise arthroscopic shoulder capsular release, a creative and innovative use of a flexible hip arthroscopy radiofrequency ablator is described.

Labral tears, extra-articular injuries, and hip arthroscopy in the athlete

Labral tears in athletes can lead to disabling hip pain and affect their athletic performance. Other intra-articular lesions, including chondral injuries, capsular abnormalities, and ligamentum teres tears, commonly coexist with acetabular labral tears. Isolated athletic injury or repetitive traumatic activity can lead to labral tears; however, underlying structural (femoroacetabular impingement) and developmental abnormalities predisposing athletes to labral pathology must be addressed. Recent studies have demonstrated lesions associated with acetabular labral tears, and that labral tears rarely occur as isolated injuries. Return to sport is favorable in athletes who have labral tears if they are properly treated with arthroscopic intervention.

Arthroscopic labral repair in the hip: surgical technique and review of the literature

Hip pain can be caused by multiple pathologies. Injuries to the acetabular labrum are the most common pathologic findings identified at the time of hip arthroscopy. Five causes of labral tears have been identified; these include trauma, femoroacetabular impingement, capsular laxity, dysplasia, and degeneration. Studies have shown the function and the importance of the labrum. To restore function of the labrum, new surgical techniques, such as suture anchor repair, have been described. The goal of arthroscopic treatment of a torn labrum is to relieve pain by eliminating the unstable flap tear that causes hip discomfort. The goals of these treatments are to maintain the function of the hip joint and decrease the development of premature arthrosis.