Clinically significant subscapularis failure after anatomic shoulder arthroplasty: is it worth repairing?

Lesser Tuberosity Osteotomy for the Management of the Subscapularis During Total Shoulder Arthroplasty

Subscapularis integrity is critical after anatomic total shoulder arthroplasty, with failure leading to potential instability, loss of function, and revision surgery. The three well-described subscapularis mobilization techniques during total shoulder arthroplasty include tenotomy, peel, and lesser tuberosity osteotomy (LTO). While several comparative studies exist, the optimal approach remains controversial. LTO has been associated with the highest healing rates, but techniques and repair constructs are highly variable. The purpose of this article was to provide an overview of LTO with attention on radiographic assessment, repair options, and clinical outcomes.

Secondary Rotator Cuff Insufficiency After Anatomic Total Shoulder Arthroplasty

» Secondary rotator cuff insufficiency is a challenging complication after anatomic total shoulder arthroplasty.» Acute tears may be amenable to open or arthroscopic repair in some instances.» Chronic attritional tears are best managed with revision to reverse shoulder arthroplasty, especially in the elderly.» Increased glenoid inclination, larger critical shoulder angle, oversized humeral components, thicker glenoid components, and rotator cuff muscle fatty infiltration have all shown to contribute to tear risk.

Techniques for Managing the Subscapularis and Addressing Failures of the Tendon in Anatomic Total Shoulder Arthroplasty

Anatomic total shoulder arthroplasty (aTSA) is an accepted treatment for a variety of degenerative conditions of the glenohumeral joint. The manner in which the subscapularis tendon is handled during the approach in aTSA is not universally agreed on. Failure of the repair after aTSA has been shown to be associated with poorer outcomes in some cases. There is no consensus on how to treat failures, as all techniques described in the literature demonstrate shortcomings. The purpose of this review is to evaluate the methods of handling the tendon in aTSA and to review options for treating failure following surgery. [Orthopedics. 2023;46(5):e264-e272.].

The long head of the biceps tendon: a valuable tool in shoulder surgery

ANATOMY AND FUNCTION

The long head of the biceps tendon (LHBT) has different properties and characteristics that render it a valuable tool in the hands of shoulder surgeons. Its accessibility, biomechanical strength, regenerative capabilities, and biocompatibility allow it to be a valuable autologous graft for repairing and augmenting ligamentous and muscular structures in the glenohumeral joint.

SHOULDER SURGERY APPLICATIONS

Numerous applications of the LHBT have been described in the shoulder surgery literature, including augmentation of posterior-superior rotator cuff repair, augmentation of subscapularis peel repair, dynamic anterior stabilization, anterior capsule reconstruction, post-stroke stabilization, and superior capsular reconstruction. Some of these applications have been described meticulously in technical notes and case reports, whereas others may require additional research to confirm clinical benefit and efficacy.

CONCLUSION

This review examines the role of the LHBT as a source of local autograft, with biological and biomechanical properties, in aiding outcomes of complex primary and revision shoulder surgery procedures.

Subscapular sparing approach for total shoulder arthroplasty: a systematic review and meta-analysis of comparative studies

Background

Total shoulder arthroplasty has been effective in treating primary glenohumeral arthritis surgically. However, the subscapularis (SSC) tendon must be released as part of the surgery's conventional approach, which could lead to postoperative problems and later tendon failure. Using a procedure that spares the tendon, Lafosse et al reported improved postoperative SSC performance. This meta-analysis will compare this approach to the standard one.

Methods

PubMed, Cochrane, and Google Scholar (pages 1-20) were searched till October 2022. The clinical outcomes consisted of the postoperative pain, adverse events, and range of motion.

Results

Only 3 studies were included in this meta-analysis. The subscapularis sparing approach tended to have better postoperative internal rotation (P = .06) and shoulder elevation (P = .1); however, the results were marginally statistically insignificant.

Conclusion

This is the first meta-analysis to compare the subscapularis sparing to the standard approach in total shoulder arthroplasty. Showing better postoperative range of motion (elevation and internal rotation), the SSC approach might be considered as a good substitute to the standard one. However, it is limited by the potentially limited exposure making it harder to use in muscular and obese patients. More randomized clinical trials are needed to reach more significant results and establish clearer indications of this approach.

[Revision of anatomic shoulder arthroplasty]

With the increasing number of primary arthroplasties, revisions of anatomical prostheses are becoming increasingly important. The most common reasons for revision are glenoid loosening, including protrusion, rotator cuff insufficiency, including instability, and early/late infection. The reconstruction of glenoid defects can be done with an autograft or allograft. Depending on the size and situation, it is carried out in one or two stages. The stemless humeral head replacement and the short-stem prostheses that have been used more frequently in recent years have significantly simplified humeral revision. Platform systems take a different approach with the option of conversion without major interventions on the glenoid or revision stem. Intraoperative complications mainly occur on the humeral side. Postoperative complications include dislocation, component loosening, and infection. Revision of anatomical to reverse arthroplasty shows better clinical outcomes and lower complication rates than anatomical revision.

Ultrasound-determined healing rates with subscapularis tenotomy versus peel after anatomic shoulder arthroplasty

BACKGROUND

Several techniques have been described for mobilizing the subscapularis tendon in anatomic total shoulder arthroplasty (TSA). The purpose of this study was to compare subscapularis tendon healing rates, as determined by ultrasound, in patients following anatomic TSA with either a subscapularis tenotomy or subscapularis peel.

METHODS

This study was a secondary analysis of patients from a previous randomized controlled trial in which patients underwent anatomic TSA and were randomized to either a tenotomy or peel approach. The primary outcome was postoperative tendon healing rates determined on ultrasound at >12 months after surgery. Secondary outcomes included postoperative tendon thickness measured on ultrasound; elbow position (neutral alignment in the belly-press position vs. posterior); internal rotation function measured with the third and fourth questions of the American Shoulder and Elbow Surgeons questionnaire; and Western Ontario Osteoarthritis of the Shoulder index. Radiographs were analyzed in patients with torn tendons.

RESULTS

One hundred patients were randomized to a tenotomy (n = 47) or peel (n = 53) approach. Postoperative ultrasound results were available in 88 patients. Tendon healing rates were 95% for tenotomy vs. 75% for peel (P = .011). The mean postoperative tendon thickness was 4 mm (standard deviation, 1.0 mm) and 4 mm (standard deviation, 1 mm) in the tenotomy and peel groups, respectively (P = .37). Internal rotation function was not associated with healing status (P = .77 and P = .22 for questions 3 and 4, respectively, of the American Shoulder and Elbow Surgeons questionnaire), nor was elbow position (P = .2) in the belly-press position.

DISCUSSION

We observed that subscapularis tenotomy had a higher healing rate than peel as determined by ultrasound in TSA patients. There was no statistically significant difference in postoperative tendon thickness in intact tendons as measured on ultrasound when comparing subscapularis mobilization techniques, nor was there any association between healing status and internal rotation function or elbow position.

Compressed autograft biceps tendon augmentation of subscapularis repair following shoulder arthroplasty

Subscapularis integrity is correlated with function following shoulder arthroplasty. Failure of healing, particularly following anatomic total shoulder arthroplasty, is associated with poor outcomes and the need for revision. Graft augmentation has been used to increase healing following rotator cuff repair but has not been commonly advocated for augmenting the subscapularis following shoulder arthroplasty. The long head biceps tendon is typically tenodesed and discarded during shoulder arthroplasty. Rather than discarding the tendon, the tendon may be compressed and applied to the subscapularis as a biologic scaffold to potentially improve subscapularis healing following shoulder arthroplasty.

Pectoralis major tendon transfer for management of subscapularis failure after anatomic total shoulder arthroplasty: technique and results

Background

Subscapularis tendon failure after anatomic total shoulder arthroplasty can lead to pain, dysfunction, and early component failure. The purpose of this study was to report on the results of pectoralis major tendon transfer for treatment of irreparable subscapularis tendon failure in the setting of prior shoulder arthroplasty.

Methods

Patients who underwent pectoralis major muscle transfer for treatment of subscapularis failure in the setting of prior total shoulder arthroplasty or hemiarthroplasty were included in the study. The entirety of the pectoralis major tendon was transferred superficial to the conjoined tendon and placed lateral to the bicipital groove.

Results

Eight patients were included in the study. All 7 patient who experienced pain in their shoulder had improvement in their pain postoperatively. Those patients with preserved active motion were able to regain that motion postoperatively. Radiographically, anterior translation was found to be temporarily improved; however, anterior instability would later recur in most cases, though this did not correlate with increased pain or decreased function.

Discussion

Management options ranging from continued observation, revision repair, pectoralis muscle transfer, or revision to reverse total shoulder arthroplasty should be considered in a setting of subscapularis failure after shoulder arthroplasty. Decision-making should be based on physiological age of the patient as well as symptoms present as well as the position and stability of the arthroplasty components.

Conclusion

Pectoralis muscle transfer can provide pain relief, improve subjective instability, and preserve function in physiological young patients with an irreparable subscapularis who have well-positioned and well-fixed anatomic shoulder arthroplasty components.

Management of Subscapularis Insufficiency After Total Shoulder Arthroplasty

The functional success of anatomic total shoulder arthroplasty (TSA) relies heavily on the healing integrity of the subscapularis tendon. Access to the glenohumeral joint is performed through a deltopectoral approach, and takedown of the subscapularis tendon is necessary in most surgeons' hands. Although initially described as a tenotomy, lesser tuberosity osteotomy and subscapularis peel are two techniques more commonly used today. Both of these options offer good results as long as proper repair is done. A subscapularis-sparing approach has more recently been advocated but is technically demanding. Failure of tendon repair can lead to early failure of anatomic total shoulder arthroplasty with accelerated glenoid loosening, decreased function, and anterior instability. Treatment options for subscapularis insufficiency include nonsurgical management, revision tendon repair, tendon reconstruction or transfer, or conversion to reverse shoulder arthroplasty. As shoulder arthroplasty continues to become increasingly prevalent, subscapularis insufficiency, too, will become more common. Accordingly, a surgeon's knowledge of subscapularis management in an arthroplasty setting must encompass treatment options for postoperative subscapularis insufficiency.

Quantifying the magnitude of local tendon injury from electrosurgical transection

BACKGROUND

Electrocautery is a common surgical technique and is often used during shoulder arthroplasty to elevate or transect the subscapularis tendon. The relative amount of tissue damage caused by cautery as opposed to sharp transection is not currently known. The purpose of this study was to examine local tissue damage resulting from electrocautery vs. sharp transection with a scalpel. We hypothesized that the electrosurgical unit would cause higher collateral tissue damage and cell death compared with sharp transection.

METHODS

Twelve cadaveric ovine shoulders were randomized to either the electrosurgical or sharp transection group. The infraspinatus tendon was isolated, and a partial-thickness transection was made using either a monopolar electrosurgical device (Bovie) or No. 10 scalpel blade. Tendon explants were then visualized with confocal microscopy to evaluate tissue architecture. A live/dead assay was performed using microscopy imaging analysis software. Comparisons between Bovie and scalpel transection were made using the Mann-Whitney U test, and the cell death percentage at standardized distances from the transection site was compared between groups using a mixed-model analysis. Significance was defined at P < .05.

RESULTS

The cellular and tendon fibril architecture was well maintained beyond the scalpel transection site, whereas Bovie transection disrupted the architecture beyond its transection path. The percentage of dead cells in the Bovie group (74.9% ± 31.2%) was significantly higher than that in the scalpel group (27.6% ± 29.9%, P = .0004). Compared with the transection site, the cell death percentage after Bovie transection significantly declined at 2.5 mm whereas that after scalpel transection significantly declined at 1 mm from the transection site.

CONCLUSION

There was a significantly higher dead cell percentage in the Bovie transection group, indicating extensive damage beyond the local incision site, compared with sharp transection. Electrosurgical transection of the ovine infraspinatus tendon ex vivo caused higher cell death and greater tissue architecture disruption compared with sharp scalpel transection.

Subscapularis Repair Prior to Subscapularis Takedown in Anatomic Shoulder Arthroplasty: Improving Anatomic Restoration and Mechanics of the Subscapularis

Traditionally, total shoulder arthroplasty is performed using a deltopectoral approach through which the glenohumeral joint is accessed by mobilization of the subscapularis. Despite several variations on the subscapularis management techniques, postoperative complications, including subscapularis deficiency and lower functional outcomes, remain an area for improvement. The purpose of this Technical Note is to describe in detail our technique for management of the subscapularis in the setting of a stemless humeral implant through which the repair is planned and almost entirely performed at the beginning of the case, prior to the subscapularis peel. This technique aims to improve outcomes after total shoulder arthroplasty by 1) avoiding the anatomic implant with anchor drilling, 2) improving procedure efficiency, and 3) anatomically "repairing" the subscapularis prior to takedown by placing anchors exactly at the repair-tension site.