Subacromial Balloon Spacer for Massive Irreparable Rotator Cuff Tears

Accelerating Efficiency in Arthroscopically Assisted Lower Trapezius Transfer: How Can We Shorten the Learning Curve?

INTRODUCTION

Arthroscopic lower trapezius tendon transfer (aLTT) is an effective strategy to treat massive rotator cuff tears by dynamically restoring the posterior aspect of the rotator cuff force couple and improving range of motion, strength, pain, and stability. aLTT is technically challenging with higher complication rates, and its learning curve has yet to be defined. We aimed to establish a learning curve for aLTT through trends in surgical time, postoperative outcomes, and complications. We hypothesized that increased surgeon experience would be associated with decreased surgical time, improved outcomes, and reduced complication rates.

METHODS

All patients who underwent primary aLTT at our institution between October 2018 and November 2022 were identified and included. Perioperative data, including diagnosis, operative time, complications, revisions, postoperative functional data, and patient-reported outcomes, were recorded and analyzed. A shoulder and elbow fellowship-trained surgeon's learning curve was determined using linear regression and cumulative sum (CUSUM) analyses. The CUSUM analysis evaluated objective differences in surgical time over the surgeon's course of practice and elucidated the completion of the learning curve.

RESULTS

Thirty-nine patients were included, with an average follow-up of 29 months. Mean surgical time was 163 minutes, with a linear decrease in surgical time throughout the study. CUSUM analysis of surgical times demonstrated a learning curve of 14 patients. When comparing the first 14 patients to the remaining 25, no difference was found in range of motion, American Shoulder and Elbow Surgeon score, and subjective shoulder value score, whereas visual analog scale pain scores at the final follow-up decreased in the proficiency phase.

CONCLUSION

This study found a notable linear decrease in surgical time and the number of cases completed without associated detriment to postoperative outcomes. At least 14 cases were required to exit the "learning phase." Further work is needed to find superior metrics to assess proficiency.

LEVEL OF EVIDENCE

4, case series.

Lower trapezius tendon transfer vs. reverse shoulder arthroplasty for massive irreparable rotator cuff tears: an in-vivo scapulohumeral rhythm dynamic radiography study

BACKGROUND

Reverse shoulder arthroplasty (RSA) and arthroscopic-assisted lower trapezius tendon (aLTT) transfer are both treatment options for massive irreparable rotator cuff tears (MIRCTs) without glenohumeral arthritis; however, the indications for each remain controversial. Although RSA is an excellent reconstructive option, preserving the joint, recentering the humeral head, and restoring in-line active external rotation with an aLTT transfer may be preferred in certain patients to better restore more normal shoulder biomechanics. In-vivo kinematics, however, have been historically difficult to evaluate. Dynamic digital radiography (DDR) provides a novel way to examine shoulder function following surgical intervention by estimating the scapulohumeral rhythm (SHR)-the ratio of humerothoracic and scapulothoracic motion. The purpose of this study was to compare SHR between aLTT transfer and RSA in the setting of nonarthritic MIRCTs with the use of DDR. We hypothesized that aLTT transfer would restore SHR to values more typical of native shoulders compared to RSA.

METHODS

DDR > 6 months postoperatively was performed on 48 shoulders, comprised of 30 RSA and 18 aLTT transfer shoulders, secondary to nonarthritic MIRCT-the diagnosis for which was validated on radiographs and magnetic resonance imaging. Manual measurements of the angle between the humerus and the midline and the lateral border of the scapula and midline were taken by 2 readers at rest, 30°, 60°, and 90° of shoulder abduction. The ratio of these measurements formed the SHR. A paired subgroup analysis was performed on 7 RSA and 7 aLTT transfer shoulders with both preoperative and postoperative DDR to evaluate for precise changes in SHR. Data were compared using descriptive statistics, and inter-rater reliability of the manual measurements was assessed with intraclass correlations.

RESULTS

The aLTT transfer cohort had a higher median rest-90° range of motion SHR of 2.30, compared to 1.83 for the RSA cohort. Subgroup analysis of the RSA cohort demonstrated a nonsignificant improvement in median rest-90° range of motion SHR from 1.84 to 2.23 following surgical intervention. The aLTT transfer subgroup's median rest-90° SHR improved significantly from 2.20 to 2.46 following surgical intervention. The inter-rater reliability was 0.99.

CONCLUSIONS

aLTT transfer is associated with an increased SHR compared to RSA in patients with nonarthritic MIRCTs by establishing a higher glenohumeral contribution compared to scapulothoracic contribution. Further work is needed to understand scapular motion in multiple planes after these surgeries and correlate SHR changes with clinical outcomes.

Subacromial balloon spacer improves isokinetic performance in patients with massive irreparable rotator cuff tear

PURPOSE

The aim of this study was to analyse clinical, functional and shoulder kinematics results using subacromial balloon spacer in nonreparable massive rotator cuff tears. Subacromial balloon spacer was hypothesised to improve shoulder kinematics and increases clinical and functional outcomes scores in nonreparable massive rotator cuff tears.

METHODS

This is a prospective study in massive rotator cuff tears. From October 2021 to October 2022, a total of 127 shoulders suffering massive rotator cuff tears were initially evaluated. All patients were evaluated preoperatively, at 6 and 12 months. Patients' patient-reported outcome measures (PROM) subjective values using visual analogue scale (VAS) and the Spanish Western Ontario Rotator Cuff Index (WORC) version were analysed. We also evaluated objective outcomes: constant score, range of movement and kinematic shoulder analysis (isokinetic test to evaluate internal and external rotation forces). Statistical analysis was conducted using SPSS software; continuous variables were presented as means and standard deviations (SDs).

RESULTS

Seventeen nonrepairable massive rotator cuff tears were finally included. Three patients required reverse shoulder arthroplasty before 6 months postoperative. After 1-year follow-up, objective and subjective (PROM) outcome scores and isokinetic measurements improved in 13 patients. Preoperative VAS improved from 6.5 ± 2.1 to 2 ± 1.9 points on average at 1-year follow-up and WORC index from 1603 ± 217.3 to 699 ± 361.6. Constant score from 42.1 ± 13.1 on average and at 1-year follow-up increased to 60.8 ± 14.7. Range of movement also improved in elevation 122.2 ± 39.3 to 166.9 ± 25.8, abduction 120.3 ± 38.6 to 134.6 ± 21.1, external rotation 30.3 ± 19.7 to 86.1 ± 13.8 and internal rotation L4-T12 on average at 1-year follow-up. Isokinetic evaluation showed functional improvement 1 year after implantation. Both internal and external rotation improved compared with their healthy shoulder. External rotation improved from 30.3° ± 19.7° preoperatively to 86.1° ± 13.8° (43.7% in the isokinetic study) and internal rotation from L4 preoperatively to L1 (49.8% in isokinetic study) on average.

CONCLUSION

Among the different alternatives for irreparable rotator cuff injuries surgical treatment, subacromial balloon spacer is an effective alternative in selected patients, both in terms of clinical-functional improvement and short-term isokinetic results.

LEVEL OF EVIDENCE

Level II.

Patients With Graft Tears Leaving the Tuberosity Covered Have Similar Functional Outcomes to Those With an Intact Graft After Superior Capsular Reconstruction

BACKGROUND

Studies to date of superior capsular reconstruction (SCR) comparing outcomes of healed grafts versus torn grafts do not separate graft tears based on location of the tear, rather they combine and report all tears as a single group.

PURPOSE/HYPOTHESIS

The purpose of this study was to correlate functional outcome with graft integrity and graft tear location after SCR with a dermal allograft. It was hypothesized that the functional outcomes of patients with an intact graft would be equivalent to those with graft tears leaving the tuberosity covered.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Patients who underwent SCR with an acellular dermal allograft at a single institution were included. Pre- and postoperative American Shoulder and Elbow Surgeons (ASES), Oxford Shoulder Score, visual analog scale (VAS) for pain, and postoperative Single Assessment Numeric Evaluation (SANE) scores were recorded. A magnetic resonance imaging scan was performed postoperatively to assess graft integrity.

RESULTS

A total of 39 patients met inclusion criteria. Mean age of patients was 60.4 ± 8.7 years; mean follow-up was 53.3 ± 25 months (range, 14-98 months). Magnetic resonance imaging performed at a mean of 17.5 months (range, 6-66 months) demonstrated an intact graft in 14 (36%); tear from the glenoid in 11 (28%), from midsubstance in 4 (10%), and from the tuberosity in 8 (21%); and complete graft absence in 2 (5%). Patients were divided into group 1 (intact graft), group 2 (tuberosity covered: tears from glenoid and midsubstance tears), and group 3 (tuberosity bare: tears from the tuberosity and dissolved or absent grafts). In group 1, there was significant improvement in ASES (37.9 to 88.5; P < .001), Oxford (25.2 to 46.2; P < .001), and VAS (6.8 to 0.9; P < .001). In group 2, there was significant improvement in ASES (32.2 to 86.1; P < .001), Oxford (23.4 to 44.2; P < .001), and VAS (7.3 to 1.3; P < .001). In group 3, there was no significant improvement in ASES (40.3 to 45.8; P = .50) or Oxford (33.5 to 31.4; P = .81), but there was a significant reduction in VAS (7.1 to 5.4; P = .03). There was no significant difference between group 1 and 2 in postoperative ASES (88.5 vs 86.1; P = .59), Oxford (46.2 vs 44.2; P = .07), VAS (0.9 vs 1.3, P = .42) and SANE (85.4 vs 83.2; P = .92) scores. However, group 3 had significantly lower ASES (45.8; P < .001), lower Oxford (31.4; P < .001), lower SANE (45.4; P < .001), and higher VAS (5.4; P < .001) scores than groups 1 and 2. There were no differences in outcomes based on sex (P = .72), previous surgery (P = .06), preoperative acromiohumeral distance (P = .57), and preoperative Goutallier stage of the supraspinatus (P = .16).

CONCLUSION

Patients who underwent SCR with a dermal allograft and developed a graft tear leaving the tuberosity covered had equivalent functional outcomes to those with an intact graft.

The Insertion of a Subacromial Balloon Spacer Can Provide Symptom Relief and Functional Improvement at a Minimum 5-Year Follow-Up in Patients With Massive Irreparable Rotator Cuff Tears

Purpose

To examine long-term patient-reported outcomes and range of motion in patients with massive irreparable rotator cuff tears (MIRCTs) who underwent subacromial balloon spacer implantation.

Methods

A retrospective review of all patients who underwent subacromial balloon placement procedure for MIRCTs at our institution was conducted. Patients with adequate preoperative and postoperative data, with at least 5 years of follow-up, were included in our study. Outcome measures were range of motion (forward elevation), American Shoulder and Elbow Surgeon (ASES) score, and visual analog scale (VAS) score. Independent t test was conducted to check for statistically significant differences between preoperative and postoperative outcome scores, with P < .05 deemed significant.

Results

Ten patients were identified: 4 were lost to follow-up beyond 2 years and were excluded. One was converted to an arthroplasty at the 1-year mark and was then lost to follow-up (conversion rate: 16.6%). Five patients had at least 5 years of follow-up after the balloon procedure and were involved in our case series analysis. Mean age was 63.1 years, and mean follow-up was 5.8 years (range, 5-7 years). Preoperatively, mean forward elevation was 110 degrees, mean ASES score was 40.68, and mean VAS score was 6.2. On follow-up, mean forward elevation was 163 degrees (P = .007), mean ASES score was 90.97 (P = .001), and mean VAS score was 0.9 (P = .004). All patients showed significant improvements in all outcome measures, and none had any significant complications.

Conclusions

In this study, we found that the use of a subacromial balloon spacer can lead to good outcomes at a minimum 5-year follow-up in patients with MIRCTs.

Level of Evidence

Level IV, therapeutic case series.

Lower Trapezius Transfer Improves Clinical Outcomes With a Rate of Complications and Reoperations Comparable to Other Surgical Alternatives in Patients with Functionally Irreparable Rotator Cuff Tears: A Systematic Review

PURPOSE

To analyze the clinical outcomes of lower trapezius transfer (LTT) for patients with functionally irreparable rotator cuff tears (FIRCT) and summarize the available literature regarding complications and reoperations.

METHODS

After registration in the International prospective register of systematic reviews (PROSPERO [CRD42022359277]), a systematic review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines was performed. Inclusion criteria were English, full-length, peer-reviewed publications with a level of evidence IV or higher reporting on clinical outcomes of LTT for FIRCT. Ovid MEDLINE, Embase, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and Scopus via Elsevier databases were searched. Clinical data, complications and revisions were systematically recorded.

RESULTS

Seven studies with 159 patients were identified. The mean age range was 52 to 63 years, 70.4% of the patients included were male, and the mean follow-up time ranged between 14 and 47 months. At final follow-up, LTT lead to improvements in range of motion, with reported forward elevation (FE) and external rotation (ER) mean gains of 10° to 66° and 11° to 63°, respectively. ER lag was present before surgery in 78 patients and was reversed after LTT in all shoulders. Patient-reported outcomes were improved at final follow-up, including the American Shoulder and Elbow Society score, Shoulder Subjective Value and Visual Analogue Scale. The overall complication rate was 17.6%, and the most reported complication was posterior harvest site seroma/hematoma (6.3%). The most common reoperation was conversion to reverse shoulder arthroplasty (5%) with an overall reoperation rate of 7.5%.

CONCLUSIONS

Lower trapezius transfer improves clinical outcomes in patients with irreparable rotator cuff tears with a rate of complications and reoperations comparable to other surgical alternatives in this group of patients. Increases in forward flexion and ER are to be expected, as well as a reversal of ER lag sign when present before surgery.

LEVEL OF EVIDENCE

Level IV, systematic review of Level III-IV studies.

Editorial Commentary: Subacromial Balloon Spacer for Irreparable Rotator Cuff Tears Produces Clinical Improvement, Yet the Mechanism of Action Is Unclear

Subacromial balloon spacers, a treatment option for massive irreparable rotator cuff tears, have been available in the United States since 2021 and much longer in Europe. The device has been described as a humeral head depressor that increases the subacromial space, centers the humeral head preventing superior migration, and improves deltoid mechanical advantage. This is not convincing. Balloon deflation occurs 3 months after implantation, eliminating the head-depressing effect, and the balloon fully degrades within 15 months. Some propose scarring in the subacromial space smoothes the acromial-humeral articulation; this is also unconvincing. The scar is not thick. Clinical studies largely report unchanged or worsened acromiohumeral interval after surgery. Short-term case series show improvement in pain and function, but comparative studies show mixed results. There may be some advantages over partial rotator cuff repair, but debridement alone may be sufficient treatment, and the generally positive short-term results do not determine whether symptom relief persists over the long term after balloon degradation. A recent clinical study does show mid-term improvement, but the mechanism remains unclear, and, if it is a result of smooth subacromial scarring, tuberoplasty may be an alternative.

Subacromial Balloon Spacer: When to Use This?

The subacromial balloon spacer is a novel treatment option for the management of massive irreparable rotator cuff tears. This device is introduced into the glenohumeral joint and acts to alleviate the acromiohumeral impingement, caused by the massive irreparable rotator cuff tear. The device also redistributes the tension around the adjacent muscles in the joint, allowing them to compensate for the torn rotator cuff tendons. By doing so, the balloon can act as a "rehabilitation accelerator", ultimately resulting in improved shoulder pain and function. Adherence to balloon indications when selecting the appropriate patient is necessary, and these include an irreparable posterosuperior rotator cuff tear, with preserved subscapularis function, minimal to no osteoarthritis, and the ability to forward flex to 90 degrees. Clinical studies have demonstrated promising potential regarding the benefit of the balloon, with numerous studies demonstrating great outcomes after its implantation. Nevertheless, future research remains necessary to render the evidence behind its utility unequivocal.

Ultrasound-Guided Deflation and Arthroscopic Removal of a Migrated Subacromial Balloon Spacer

Full-thickness massive irreparable rotator cuff tears present a demanding challenge for the surgeon. The subacromial balloon spacer is a novel biodegradable implant used to treat massive, irreparable rotator cuff tears. There have, however, been several isolated reports of balloon migration. This Technical Note describes ultrasound-assisted balloon deflation followed by arthroscopic removal of a symptomatic dislodged balloon.