Subacromial Balloon Spacer Implantation for Massive Irreparable Rotator Cuff Tears Is Associated With Restoration of the Acromiohumeral Interval and Glenohumeral Center of Pressure: A Systematic Review and Meta-Analysis of Controlled Laboratory Studies

Tuberoplasty reduces resistance force in dynamic shoulder abduction for irreparable rotator cuff tears: a cadaveric biomechanical study

BACKGROUND

Arthroscopic tuberoplasty is an optional technique for managing irreparable rotator cuff tears. However, there is a lack of studies investigating the resistance force during shoulder abduction in cases of irreparable rotator cuff tears and tuberoplasty.

HYPOTHESES

In shoulders with irreparable rotator cuff tears, impingement between the greater tuberosity (GT) and acromion increases the resistance force during dynamic shoulder abduction. Tuberoplasty is hypothesized to reduce this resistance force by mitigating impingement.

STUDY DESIGN

Controlled laboratory study.

METHODS

Eight cadaveric shoulders, with a mean age of 67.75 years (range, 63-72 years), were utilized. The testing sequence included intact rotator cuff condition, irreparable rotator cuff tears (IRCTs), burnishing tuberoplasty, and prosthesis tuberoplasty. Burnishing tuberoplasty refers to the process wherein osteophytes on the GT are removed using a bur, and the GT is subsequently trimmed to create a rounded surface that maintains continuity with the humeral head. Deltoid forces and actuator distances were recorded. The relationship between deltoid forces and actuator distance was graphically represented in an ascending curve. Data were collected at five points within each motion cycle, corresponding to actuator distances of 20 mm, 30 mm, 40 mm, 50 mm, and 60 mm.

RESULTS

In the intact rotator cuff condition, resistance forces at the five points were 34.25 ± 7.73 N, 53.75 ± 7.44 N, 82.50 ± 14.88 N, 136.25 ± 30.21 N, and 203.75 ± 30.68 N. In the IRCT testing cycle, resistance forces were 46.13 ± 7.72 N, 63.75 ± 10.61 N, 101.25 ± 9.91 N, 152.5 ± 21.21 N, and 231.25 ± 40.16 N. Burnishing tuberoplasty resulted in resistance forces of 32.25 ± 3.54 N, 51.25 ± 3.54 N, 75.00 ± 10.69 N, 115.00 ± 10.69 N, and 183.75 ± 25.04 N. Prosthesis tuberoplasty showed resistance forces of 29.88 ± 1.55 N, 49.88 ± 1.36 N, 73.75 ± 7.44 N, 112.50 ± 7.07 N, and 182.50 ± 19.09 N. Both forms of tuberoplasty significantly reduced resistance force compared to IRCTs. Prosthesis tuberoplasty further decreased resistance force due to a smooth surface, although the difference was not significant compared to burnishing tuberoplasty.

CONCLUSION

Tuberoplasty effectively reduces resistance force during dynamic shoulder abduction in irreparable rotator cuff tears. Prosthesis tuberoplasty does not offer a significant advantage over burnishing tuberoplasty in reducing resistance force.

CLINICAL RELEVANCE

Tuberoplasty has the potential to decrease impingement, subsequently reducing resistance force during dynamic shoulder abduction, which may be beneficial in addressing conditions like pseudoparalysis.

Subacromial Balloon Spacer for the Massive Irreparable Cuff Tear

PURPOSE OF REVIEW

The purpose of the review is to provide an updated overview of a relatively novel but controversial surgical device (InSpace subacromial balloon, Stryker, Kalamazoo, MI) that can be readily incorporated into the armamentarium of the shoulder surgeon. The authors review the critical clinical and surgical decision-making aspects of InSpace. A recommended surgical technique and rehabilitation protocol are outlined. The authors present a nuanced view of the balloon spacer in the continuum of care of the irreparable rotator cuff tear.

RECENT FINDINGS

Within the last year, two Level I clinical trials have been published, and the data from these studies offer conflicting evidence regarding the utility of the subacromial balloon spacer. The current review contrasts these two recent studies and offers a framework by which the available evidence can be practically understood with respect to clinical decision-making. The literature currently supports a limited indication for use of InSpace: the elderly, low-demand patient with preserved active range of motion with an operatively irreparable, posterosuperior rotator cuff tear with an intact subscapularis. The InSpace subacromial balloon spacer is a simple device that can yield substantial improvements in clinical outcomes among a subset of patients with irreparable rotator cuff tears. InSpace is not a panacea for the complex, irreparable rotator cuff tear. Individualized decision-making is necessary in this diverse and challening patient population.

Subacromial Balloon Spacer Does Not Reduce the Retear Rate for Massive Rotator Cuff Tears: A Comparative Study

PURPOSE

To determine whether a subacromial spacer decreases the recurrent rotator cuff tear rate in arthroscopically managed massive rotator cuff tears (MRCTs) with 1 year of follow-up.

METHODS

We selected all patients who met the following criteria: (1) an MRCT excluding Collin type A, (2) Goutallier stage equal or less than 2, and (3) complete arthroscopic repair of the MRCT. Patients were allocated into 2 groups: A (without subacromial spacer) or B (with subacromial spacer) for a prospective evaluation 1 year after surgery. The primary outcome was the retear rate, determined with magnetic resonance imaging (MRI) according to the classification of Sugaya. Secondary outcome measures were the functional outcomes using visual analog score, Shoulder Subjective Value, and Constant-Murley Score. Preoperative rotator cuff characteristics such as number of tendons involved and the tear retraction also were evaluated. Patient-related data such as sex, age, laterality, history of smoking, and diabetes mellitus were analyzed.

RESULTS

In total, 31 patients were included in group A and 33 in group B. Preoperatively, only 2 differences were found between both groups: a significant (but not clinical) greater Constant score in group A (P = .034) and a slightly greater retraction of the supraspinatus in group B (P = .0025). The overall retear rate between the 2 groups was similar regarding the number of patients (P = .746) and the total number of tendons involved in the recurrent tear (P = .112). At 1-year follow-up, no differences were found in VAS (P = .397), SSV (P = .309), and Constant score (P = .105).

CONCLUSIONS

In reparable massive rotator cuff tears (excluding Collin type A), the augmentation of repair with a subacromial spacer did not significantly reduce the number of patients with recurrent rotator cuff tears identified by MRI. It was also ineffective in reducing the number of re-ruptured tendons in these patients. No patient-reported or clinically significant findings were noted in Constant, SSV, and VAS scores at 1-year postoperative follow-up. Patients with MRI findings of a healed rotator cuff (Sugaya 1-3) had better clinical outcomes compared with those without.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.