Eddie Y. Lo

Case: Two septuagenarian women presented with chronic periprosthetic scapular spine fractures after reverse total shoulder arthroplasty (RTSA) placement. Preoperative radiographs revealed a displaced unstable scapular spine fracture with scapula notching and onlay humeral position. One case additionally demonstrated uptilted baseplate placement. Both patients underwent concurrent revision RTSA with fixation of the scapular spine to correct component malposition and reduce glenohumeral tension. At 27-month follow-up, both achieved radiographic union, pain reduction, and functional gains without complications. Conclusion: The authors present a novel strategy to correct the underlying biomechanical stressors of an overtensioned RTSA construct while stabilizing the scapular spine fractures, resulting in excellent healing and functional recovery.

» Proximal humerus bone loss (PHBL) is a challenging issue in the setting of reverse total shoulder arthroplasty, particularly during revision surgeries. » PHBL can compromise the deltoid moment arm, soft tissue attachments, and stability of the humeral and glenoid components. » Causes of PHBL are multifactorial, and the degree of bone loss can vary widely among patients. » Treatment options include long-stem reconstruction prostheses, cementoplasty, reverse total shoulder allograft prosthesis composite reconstruction, proximal humerus replacement/endoprosthesis, and custom 3D-printed reconstruction. » Each treatment option has unique advantages and limitations, emphasizing the importance of individualized management plans tailored to patient needs. Level of Evidence: Level IV. See Instructions for Authors for a complete description of levels of evidence.

Background: Rotator cuff repair techniques have evolved over time. The original techniques were open procedures, then surgeons adopted arthroscopic repair procedures with anchors and implants. Today, rotator cuff repair has evolved to be performed as an arthroscopic transosseous technique that is again performed without the use of anchors. Description: In this video, the 5 essential steps of arthroscopic transosseous repair will be demonstrated. (1) Position the patient in either the beach chair or lateral decubitus position. (2) Utilize 4-portal arthroscopy, which allows a consistent vantage point while having 3 other portals for instrumentation. (3) Perform just enough bursectomy to expose the rotator cuff. (4) Anatomically reduce the rotator cuff anatomy where possible. (5) Triple-load the transosseous tunnels with high-strength sutures in order to maximize the biomechanical strength of the repair. Alternatives: Alternative surgical techniques include open rotator cuff repair and single and double-row rotator cuff repair using anchors. Rationale: The goal of any rotator cuff repair is to anatomically restore the rotator cuff. The fundamental principles include a strong initial biomechanical fixation, cuff footprint anatomy restoration, and maximization of biological factors to promote healing of the rotator cuff. Rotator cuff repair was originally performed as an open procedure, which allows for direct visualization of the tear and repair; however, open repair requires some level of deltoid splitting, which can potentially affect postoperative early mobilization. Single-row and double-row cuff repairs can both be performed arthroscopically. Proponents of the double-row procedure prefer that technique for its footprint restoration and stronger biomechanical fixation; however, the double-row procedure can result in overtensioning of the repair and can lead to medial-based rotator cuff failures. Proponents of the single-row procedure prefer that technique for its ease of operation, fewer implants, lower cost, and low repair tension; however, the single-row procedure fixes the tendon at a single point, limiting the repaired footprint, and can be associated with lower fixation strength. The arthroscopic transosseous rotator cuff repair achieves all of the above goals as it provides strong initial fixation and anatomic footprint restoration, which allows maximal patient biology for healing. Expected Outcomes: There are numerous studies that can attest to the success of arthroscopic transosseous repair. Some of the benefits include decreased health-care costs and postoperative pain levels. In a 2016 study of 109 patients undergoing arthroscopic transosseous rotator cuff repair, Flanagin et al. reported a mean American Shoulder and Elbow Surgeons (ASES) score of 95 and a failure rate of 3.7% at mid-term follow-up ¹ . Similarly, in a study comparing transosseous repair to transosseous equivalent repair, Srikumaran et al. reported that patients undergoing transosseous repair had a mean ASES score of 92 and a failure rate of 14%, with no significant differences between treatment groups ² . Finally, in a study assessing the results of arthroscopic transosseous rotator cuff repair at >10 years postoperatively, Plachel et al. reported a mean ASES score of 92 and a failure rate of 27% ³ . Important Tips: Compared with conventional rotator cuff with anchors, the transosseous cuff repair can lead to cut-out of the repair sutures from the bone. Use a 4-portal arthroscopy technique, which will help the surgeon visualize all tear configurations while instrumenting them. Perform just enough bursectomy, in order to preserve the growth factors for cuff healing. Take care to minimize tuberosity trauma as a result of burring. Prepare the transosseous tunnels with a wide bone bridge. Load each tunnel with 3 high-strength sutures in order to maximize repair strength. Restore the rotator cuff footprint to facilitate tissue healing. Acronyms and Abbreviations: ASES = American Shoulder and Elbow Surgeons RCR = rotator cuff repair ATRCR = arthroscopic transosseous rotator cuff repair ARCR = arthroscopic rotator cuff repair PDS = polydioxanone suture ROM = range of motion SSV = Subjective Shoulder Value FF = forward flexion OR = operating room FU = follow-up

Background: Cementless reverse shoulder arthroplasty has become increasingly popular because of the improved implant design, porous ingrowth surface, and surgical techniques. When avoiding the risks of cement use, a press-fit arthroplasty stem that has been implanted may not feel immediately stable, especially if the medullary canal size is in between standard stem diameters. To help surgeons improve fixation and avoid overstuffing the medullary canal, we present the matchstick autograft augmentation technique. The use of humeral autograft, analogous to impaction grafting in hip arthroplasty, has been reported to have promising short-term outcomes ^2,3 . This technique of using humeral autograft material, dubbed matchstick autografts because of their shape and size, allows for optimization of humeral stem stability with the option of smaller cementless humeral implants. By avoiding overstuffing of the medullary canal, this technique aims to reduce the incidences of intraoperative fracture, postoperative stress shielding, and potential implant loosening ^4–6 . Description: Cementless reverse total shoulder arthroplasty is routinely performed via the anterosuperior approach ⁷ ; however, a deltopectoral approach can be utilized if desired. The canal is sequentially broached with implant trials until the tactile feedback demonstrates axial and rotational stability. In cases in which tactile feedback during implantation demonstrates slight movement, the smaller implant size can be selected and augmented with matchstick autograft. An oscillating saw is utilized to cut the edges of the previously resected humeral head in order to expose the subchondral bone surface. Graft sticks about 20 mm in length and 1 to 3 mm in width are then fashioned. Humeral trials are then implanted with the matchstick grafts placed lengthwise alongside the humeral stem. Axial and rotational press-fit is again assessed. If adequate, the formal humeral implant is selected and implanted in position. As in conventional impaction grafting, the grafts are compressed to the side of the humeral canal, but they offer more corticocancellous structure than bone chips. This technique is applicable even in some fracture scenarios. Alternatives: When a specific press-fit humeral stem size does not achieve adequate stability, there are typically 3 surgical alternatives. First, a larger stem size can be selected. Second, the implant can be inserted deeper to achieve press-fit stability. Third, cement can be added to fill the medullary canal and create immediate stability. Rationale: When implanting the humeral prosthesis, the operating surgeon’s primary goal is stem stability. When faced with lack of stability, the surgeon can select a larger humeral stem, risking stress shielding; implant the stem deeper, compromising length and risking humeral fracture; or consider a cemented implant. In order to minimize the risk of intraoperative cardiopulmonary events and complicated subsequent revision surgeries ⁸ , the use of cement should be avoided if at all possible. Shoulder surgeons have reported grafting techniques, analogous to hip impaction grafting, that have yielded good success ³ . The technique that we describe utilizes a matchstick structural autograft that helps improve cementless fixation in primary humeral implantation cases and allows for the use of a smaller stem. The structural shape of the graft allows this technique to be utilized even in selected proximal humeral fractures. Expected Outcomes: Other studies have reported on the use of softer cancellous autografts to stabilize humeral implants in shoulder arthroplasty. In a study of 286 arthroplasties with a minimum follow-up of 2 years, Lucas et al. reported that 267 humeral stems (93.3%) had not subsided ³ . Humphrey and Bravman used cancellous autograft to achieve metaphyseal centering of the humeral component in 53 patients, with no cases of humeral implant loosening at 12 months ² . Lo et al. reported 91% tuberosity healing in their series of cementless reverse total shoulder arthroplasties augmented with matchstick autografts ¹ , with no cases of aseptic humeral stem loosening. Montemaggi et al. used matchstick autografts to augment 46 primary cementless reverse total shoulder arthroplasties and found zero instances of humeral loosening at 1-year follow-up ⁹ . Important Tips: The strongest humeral matchstick grafts come from the subchondral surface. After creating the graft, it is palpated for structural integrity. A stiffer or softer graft can be chosen, depending on surgeon preference. Surgeons can try impacting the graft with humeral trials to assess the stem stability prior to final implantation. Acronyms and Abbreviations: RTSA = reverse total shoulder arthroplasty FX = fracture 3D CT = 3-dimensional computed tomography XR = x-ray FU = follow-up

Background: The use of cementless diaphysis-fitting stems has been shown to be an effective treatment option for cases of metadiaphyseal humeral fracture. Complex metadiaphyseal fractures are those that extend below the surgical neck into the diaphysis, which can compromise the metaphyseal fixation of typical arthroplasty designs. The presently described surgical technique circumvents the potential risks associated with the use of cement while also permitting the treatment of common concomitant pathologies, such as arthritis and rotator cuff tendinopathy. Evidence supports the efficacy of this technique, showcasing consistent rates of healing, pain relief, and functional recovery, as well as acceptable complication rates compared with alternative surgical options. Description: The surgical procedure is performed with the patient in a modified beach chair position. A deltopectoral approach is utilized in order to expose the humerus and glenoid. In cases in which the tuberosity is fractured, it is carefully tagged for subsequent repair. The metadiaphyseal extension of the fracture is exposed, and reduction is performed with cerclage cable augmentation as needed. When direct reduction proves challenging, the humeral prosthesis is utilized to aid in reduction. Full-length humeral radiographs and a humeral sounder are utilized to guide the placement of a trial prosthesis, ensuring that the stem spans 2 canal diameters past the fracture and restores the appropriate humeral length. The medullary stem is utilized as support for fracture fragment reduction, with use of a combination of bone stitching and cerclage cables as required. Fractures with compromised proximal humeral bone stock can be further augmented with extramedullary strut allografts and cerclage cables. The allograft strut fixation acts as a neutralization plate to maintain rotational control. The joint is reduced, and fixation of the subscapularis and tuberosity is achieved with use of a transosseous suture technique. This technique combines the use of arthroplasty as well as standard osteosynthesis principles to treat complex metadiaphyseal humerus fractures. Alternatives: Nonoperative treatment may be indicated in a primary setting and represents a multifactorial patient-specific decision. Other surgical options include open reduction with internal fixation with plates or an intramedullary humeral nail, and cemented long-stem arthroplasty. If the fracture is too distal and the surgeon is unable to achieve a length of 2 canal diameters for distal fixation, alternative treatment strategies such as cementation may be required. Rationale: This procedure is most often performed in elderly patients with osteoporosis, who often also have comminuted fracture patterns and conditions such as glenohumeral arthritis or chronic rotator cuff pathology ^1,5,6,13,15 . Whereas open reduction and internal fixation (ORIF) can be effective in younger patients, it poses higher risks of complications in patients with osteoporosis ^{1,3,9,14–16} . Neither ORIF nor intramedullary nailing addresses concurrent pathologies. Another alternative technique involves the use of a cemented stem; however, a cementless approach eliminates theoretical risks of cement use, allows easier revisions, and achieves comparable outcomes ^9,16,20 . In summary, cementless long-stem RTSA offers consistent healing rates, satisfactory outcomes, and favorable results. Expected Outcomes: Cementless long-stem reverse total shoulder arthroplasty (RTSA) is a viable alternative for elderly patients with metadiaphyseal proximal humeral fractures. This technique shows consistent healing rates, pain relief, shoulder function restoration, and an acceptable complication rate. In a study of 14 patients who underwent cementless long-stem RTSA from September 2017 to August 2020, all patients showed improved outcomes and radiographic evidence of union at an average of 13 months postoperatively. Minor complications have been reported, such as transient neuropathy, tuberosity nonunion, and humeral stress shielding. Important Tips: This technique is optimal for elderly patients with osteoporotic bone, comminuted fractures, glenohumeral arthritis, and/or rotator cuff pathology. Long comminuted fractures require bridging fixation, spanning 2 canal diameters beyond the fracture site. Patients with compromised proximal humeral bone stock may require allograft strut augmentation. The surgical principle integrates standard arthroplasty for joint length restoration, a relative fracture stability concept by spanning complex fracture segments, and an absolute stability concept by direct fragment alignment. Acronyms and Abbreviations: RTSA = reverse total shoulder arthroplasty IMN = intramedullary nail ORIF = open reduction and internal fixation AVN = avascular necrosis AP = anteroposterior CT = computed topography TSA = total shoulder arthroplasty XR = plain radiographs FU = follow-up SST = simple shoulder test ASES = American Shoulder and Elbow Surgeons DASH = Disabilities of the Arm, Shoulder and Hand PROM = patient-reported outcome measures ROM = range of motion

Background: With the increased utilization of reverse total shoulder arthroplasty (RTSA), there has been a corresponding increase in the incidence of and demand for revision RTSA ³ . In cases in which the patient has undergone multiple previous surgeries and presents with well-fixed shoulder implants, even the most experienced shoulder surgeon can be overwhelmed and frustrated. Having a simple and reproducible treatment algorithm to plan and execute a successful revision surgery will ease the anxiety of a revision operation and avoid future additional revisions. The extraction techniques described here strive to preserve the humeral and glenoid anatomy, hopefully facilitating the reimplantation steps to follow. Description: The main principles of implant removal include several consistent, simple steps. In order to revise a well-fixed humeral implant, (1) identify the old implants; (2) create a preoperative plan that systematically evaluates the glenoid and humeral deficiencies; (3) prepare consistent surgical tools, such as an oscillating saw, osteotomes, and/or a tamp; (4) follow the deltoid; (5) dissect the soft tissue with a sponge; (6) dissect the bone with use of an osteotome; and (7) remove the humeral stem in rotation. In cases in which there is also a well-fixed glenoid implant, the surgical procedure will require additional steps, including (8) exposure of the anteroinferior glenoid, (9) disengagement of the glenosphere, and (10) removal of the glenoid baseplate in rotation. Alternatives: Alternatives to revision RTSA include nonoperative treatment, implant retention with conversion of modular components, extensile revision surgical techniques, and/or mechanical implant removal. With the advent of modular humeral and glenoid components, surgeons may choose to change the implant components instead of removing the entire humeral and glenoid implants; however, repeat complications may occur if the previous implant or implant position was not completely revised. When confronted with a tough humeral explantation, an extensile surgical approach involves creating a cortical window or humeral osteotomy to expose the humeral implant. This approach can compromise the humeral shaft integrity, leading to alternative and less ideal reconstruction implant choices, the use of cerclage wires, and/or the use of a strut graft, all of which may complicate postoperative mobilization. If glenoid implant removal is necessary, the glenosphere is removed first, followed by the underlying baseplate component(s). If the glenosphere is stuck or if screws are cold-welded, the use of a conventional mechanical extraction technique with a burr or diamond saw may be required; however, this may lead to additional metal debris and intraoperative sparks. Rationale: Revision RTSA can lead to high complication rates, ranging from 12% to 70% ² , which will often require additional revision surgeries ⁴ . The first steps to all revision RTSA procedures include careful surgical exposure and component explantation. A simplified approach to expose the humerus and glenoid, coupled with a systematic and atraumatic approach to remove the implants without inadvertent injuries, will prevent surgical complications and the need for re-revision. The proposed comprehensive technique hopefully will allow precise removal of the humeral and glenoid implants while also preserving the remnant humerus or glenoid for future reconstruction. Expected Outcomes: Few studies have evaluated postoperative patient outcomes in revision RTSA. Chalmers et al. performed a meta-analysis and found that patients were able to achieve a mean elevation of 106°, a mean American Shoulder and Elbow Surgeons score of 63, and a mean Single Assessment Numeric Evaluation score of 52 ² . Boileau showed very similar outcomes, with a mean elevation of 107° and a mean adjusted Constant score of 62 ¹ . These outcomes are slightly inferior to those of primary RTSA, but patients remain satisfied with their improvement from their preoperative function. Important Tips: Preoperative preparation will reduce intraoperative reparation. Know the existing implant and the unique features of its design, understand the patient anatomy including bone defects, and anticipate all of the potential tools that may be needed. Know your anatomy. The anteromedial deltoid edge will help you identify the scarred-in humeral shaft. Da Vinci said that simplicity is the ultimate sophistication. Some of the most common surgical tools and instruments can be more effective than custom-designed ones. The implant should be removed in rotation. There are some company-specific explantation instruments that can be very helpful. Give the appropriate ones a try, but be prepared to consider alternative solutions. Acronyms and Abbreviations: RTSA = reverse total shoulder arthroplasty CT = computed tomography FE = forward elevation