The number of total shoulder arthroplasty (TSA) cases continues to increase year over year. In a nationwide review within the United States from 2016 to 2020, more than 154,400 patients were identified as having undergone a primary TSA.1 By 2020, reverse total shoulder arthroplasty (rTSA) accounted for nearly 70% of all primary shoulder replacement cases, representing a 15% increase from 2016. With increased utilization, there is an expected rise in complications, such as glenoid or humeral stem loosening, infection, and periprosthetic fractures. Historic rTSA complication rate is estimated to be 10% to 47%, which is a wide range due to the differences in how studies define major and minor complications and the evolution of prosthesis design since the procedure was first introduced more than 30 years ago.2 Modern studies estimate the rate is lower (10% to 20%) now with advances in surgical technique and generational experience with reverse total shoulder arthroplasty.3 Nonetheless, this is still a relatively high rate. Periprosthetic fractures, which are generally considered major complications, can occur in 1% to 2% of all rTSA cases.4 For patients who are older, active, and have several medical comorbidities (eg, osteoporosis, diabetes mellitus, rheumatoid arthritis, and obesity), there is a greater chance of these fractures occurring because of poor overall bone quality. Treatment options include nonoperative care, open reduction and internal fixation (ORIF), and revision total shoulder arthroplasty. Early design choices in humeral component size, particularly length and endosteal fit, can make ORIF difficult due to a lack of area around the stem for fixation and concern for fixation failure.3 In addition, rTSA done for proximal humeral fractures often results in tuberosity resorption, causing worsened postoperative range of motion and further limitation of proximal fixation points, which is a concern when considering ORIF. Currently, operative management is difficult, and there is no superior option to gain robust fixation about the humeral component. Dual plating constructs have been shown to be biomechanically superior to single plate constructs in diaphyseal humerus fractures.5 However, large humeral stems that fill the proximal canal can potentially eliminate the possibility of proximal screw fixation necessary for these constructs. Thus, the authors present a retrospective case series fashioning a lateral blade-like compression plate augmented by an anterior compression plate and circumferential cerclage cables to create a robust fixation construct for complex periprosthetic fractures around a well-fixed large diameter humeral stem that does not rely on proximal screw fixation. This technique allows patients with limited proximal screw fixation options and an ingrown stable humeral stem not amenable to revision arthroplasty to undergo stable and predictable fixation of their periprosthetic fracture. TECHNIQUE After inducing adequate general anesthesia, the patient was positioned supine on a radiolucent table with the head of the bed slightly elevated, and a bump was placed under the ipsilateral scapula. The operative arm was placed on a radiolucent arm board to obtain appropriate orthogonal radiographs (ie, Grashey and Scapular-Y views) to assess the glenohumeral joint and prosthesis. The left upper extremity was prepped and draped in normal sterile fashion before the timeout was performed. To expose the surgical site, the previous reverse total shoulder arthroplasty incision was extended distally and proximally as necessary. The deltopectoral interval was then developed without exposing the glenohumeral joint. The deltoid insertion was only elevated in as much was required to place the lateral like blade plate. The brachialis was split longitudinally along the anterior aspect of the humerus to gain access to the fracture site, which was debrided. Fracture edges were debrided using sharp dissection. Fracture reduction is the most challenging aspect of this technique because the periprosthetic fracture tends to be transverse. To reduce and stabilize the fracture provisionally, manual manipulation, pointed reduction clamps, and modified reduction clamps were used. Intraoperative fluoroscopy was used to assess the quality of reduction. Following anatomic reduction, circumferential dissection was done around the proximal aspect of the humerus, staying proximal to the insertion of latissimus dorsi. Two to three 2.0 mm cerclage cables were then passed proximally to the latissimus dorsi but not tensioned. It is important to be aware of the radial nerve to decrease the risk of iatrogenic nerve injury. Staying as close as possible to the latissimus dorsi and tracking the position of the radial nerve ensures its safety. An appropriate length VariAx 2 Compression Plate (Stryker Orthopedics, Portage, MI, USA) was then bent to a near 90-degree angle using a combination of tabletop and bending irons. The plate was cut between the holes creating an extended right-angle blade-like construct. The deltoid muscle was retracted, exposing the shoulder of the prosthesis. Residual overlying soft tissue at the lateral shoulder of the prosthesis was split just enough to allow the blade-like construct to sit directly on the shoulder of the prosthesis and to serve as a point of fixation. To compress across the fracture, eccentric screws were placed distally in the oblong holes. Similar to a traditional blade plate inserted into bone, the blade component serves as a fixed-angle rigid point of fixation proximal to the fracture by resting on the shoulder of the prosthesis in lieu of bone. This allows for fracture compression courtesy of eccentric screw placement distal to the fracture (Fig. 1A).FIGURE 1: (A) Blade perched on the shoulder of the prosthesis to allow for a point of fixation to compress against while placing distal fixation. (B) Compression of the proximal plate to the humerus by tensioning the proximal cables with the blade fully engaging the shoulder of the prosthesis. (C) Final intraoperative lateral fluoroscopic image.A second appropriate-length VariAx 2 Compression Plate (Stryker Orthopedics, Portage, MI) was placed along the anterior surface of the humerus with anterior-to-posterior screws placed distal to the stem. The previously placed cerclage cables were then terminally tightened around both plates, providing fixation proximally to where bone stock was minimal due to the large humeral stem and resorption of tuberosities (Fig. 1B). The titanium composition of the plates utilized functionally allowed for the flexibility necessary for the plates to contour appropriately to the humerus while tensioning (Fig. 1C). The deltopectoral interval and deep subcutaneous tissue were then closed with Vicryl 0 suture. Interrupted Monocryl 2-0 sutures close the more superficial layer, and a running subcuticular Monocryl 3-0 suture fully closed the incision. Postoperatively, patients were made nonweight-bearing and instructed to avoid pushing, pulling, and lifting motions with the operative arm. A standard sling was provided for comfort, which they could wean out of at 6 weeks as tolerated. Patients were encouraged to do Codman pendulums, along with elbow, wrist, and hand range of motion, following surgery, while unrestricted active and passive shoulder range of motion was allowed after the 2-week postoperative visit. Given the transition to unrestricted range of motion at 2 weeks, we feel that the lack of shoulder motion at final follow-up was related in large part to a prefracture lack of motion, although we could not objectively verify this. Weight bearing as tolerated commenced following fracture union. EXPECTED OUTCOMES Institutional review board approval was not necessary because the series consisted of only up to 3 patients in accordance with the policies by Allina Health Institutional Review Board. All patients included in the retrospective case series had a moderately displaced periprosthetic fracture at or distal to a well-fitted left reverse total shoulder arthroplasty (rTSA) stem that did not allow for adequate proximal screw fixation given its large diameter filling the entire medullary canal and were classified as American Society of Anesthesiologists Physical Status III. The periprosthetic fractures were caused by a low-energy ground-level mechanical fall. Table 1 has the full demographic, follow-up, and range of motion (ROM) data that were collected. TABLE 1 - All 3 Cases’ Demographics, Injury Classifications, Follow-Up, and Range of Motion Compared With One Another With Averages as Applicable N = 3 Case 1 Case 2 Case 3 Average Sex Female Male Female — Age at ORIF, y 79 67 51 65.7 BMI 38.4 22.3 18.6 26.4 ASA classification III III III — Wright and Cofield fracture classification A A A — Time from ORIF to union, mo 3.5 13.9 3.2 6.9 Time from ORIF to final follow-up, mo 18.1 13.9 34.5 22.2 Active ROM (Abd), degrees 75 45 90 70.0 Active ROM (FE) degrees 80 30 90 66.7 Passive ROM, degrees 95-100 110 100 102.5 Abd indicates abduction; ASA, American Society of Anesthesiologists; BMI, body mass index; FE, flexion-extension; ORIF, open reduction internal fixation; ROM, range of motion. Case 1 This is a 79-year-old female with a significant history of hypothyroidism, hyperlipidemia, diabetes mellitus type II complicated by polyneuropathy, obesity (body mass index: 38.4), former smoker (quit in 1975, 11 pack years), and pulmonary hypertension. She underwent elective rTSA due to chronic left shoulder pain then fell from a scooter 1 year later where she injured her left shoulder and developed a moderately displaced humeral periprosthetic fracture. Approximately 1 year after undergoing the modified revision fixation technique, she was noted to have 75 degrees of active abduction, 80 degrees of active flexion-extension, and 100 degrees of passive ROM. Union was achieved at 3.5 months postoperatively. Case 2 A 67-year-old male who had been smoking for 52 years (started with 2 packs a day at 15 y old then reduced to 0.5 packs a day in his 30s) and spent most of his adult life drinking heavily (complicated by chronic alcohol-associated liver disease) had a fall while intoxicated that resulted in a significantly displaced subacute humeral fracture. This was treated with rTSA. About 1 year later, he slipped in cooking oil and experienced a mildly comminuted fracture with moderate angulation deformity and moderate displacement. This patient was lost to follow-up after his 6-week appointment, only to return 14 months postfixation following a second fall directly onto the left elbow 2 weeks earlier. His periprosthetic fracture was healed, and it was noted that his prosthesis had subsided 1 centimeter making this the only known complication (Fig. 2E-F). Fortunately, his fixation was robust enough to prevent a second periprosthetic fracture. He was noted to have improved by 25 degrees of active abduction (20 vs. 45 degrees) and 20 degrees of passive ROM (90 vs. 110 degrees) postfixation as compared with post-rTSA (Fig. 2). Union was documented at 13.9 months, although this was likely inaccurate because the patient was lost to follow-up for several months.FIGURE 2: A 67-year-old male who demonstrates tuberosity resorption and a large humeral stem with minimal bone stock available at injury on (A) anteroposterior and (B) lateral. He had radiographs taken at 6 weeks postoperatively (C-D). His final postoperative radiographs taken at the 14-month mark show subsidence of 1 cm after sustaining a second fall(E-F).Case 3 A 51-year-old female with a significant history of diabetes mellitus type I, chronic pancreatitis treated with pancreatectomy and islet cells transplant, prior heavy usage of alcohol, and a current smoker of 15 years at 0.5 packs a day. After a fall that resulted in rTSA, she had another fall at home where she developed a mildly comminuted and moderately displaced humeral periprosthetic fracture. She underwent the modified revision fixation procedure due to uncontrollable pain. Within the last year, she had multiple visits to the emergency department for falls, likely due to alcohol intoxication, and that has caused persistent pain. Her postfixation ROM was good with 90 degrees of abduction, 90 degrees of flexion-extension, and 100 degrees passively. Union was achieved at 3.2 months postoperatively (Fig. 3).FIGURE 3: A 51-year-old female who demonstrates tuberosity resorption and a large humeral stem with minimal bone stock available at injury on (A) anteroposterior and (B) lateral. She had final postoperative radiographs taken 21 months after the revision fixation procedure (C-D).COMPLICATIONS Despite the patients’ many severe comorbidities increasing the risk of complications, there were no failures of fixation, additional reoperations, nor any iatrogenic nerve injuries. Radiographic imaging demonstrated fully healed periprosthetic fractures, stable hardware, and no evidence of septic loosening. All patients went on to union at an average of 6.9 months (range 3.2 to 13.9 mo). Radiographic union was defined as callus bridging or, for direct healing, callus bridging across the fracture line. A limitation of this study is that it is a retrospective single-surgeon case series with a small cohort of 3 patients. Despite the small sample size, all patients had >1 year follow-up with a mean follow-up length after fixation of 22.2 months (range: 18.1 to 34.5 mo). A wide array of ages was represented (mean: 65.7 y; range: 51 to 79 y), which allows for some generalizability of the results. In addition, this technique provides robust fixation around large diameter humeral stems and is easily reproducible by other orthopedic surgeons. Future studies could be designed to directly compare the results of the present study’s fixation construct with other types of internal fixation for periprosthetic humeral fractures. Patients could also be followed for a longer period to improve long-term outcomes and complication reporting. Another limitation is the lack of patient-reported outcomes. In the future, a prospective study could be designed to collect patient-reported outcomes. CONCLUSION The authors describe a novel modified method of fixation that consists of a lateral blade-like compression plate that was augmented by an anterior compression plate and circumferential cerclage cables. As evidenced by the retrospective case series, this technique allows for robust proximal humeral fixation in patients with poor bone stock and a large index reverse total shoulder arthroplasty stem. The fixation can withstand additional low-energy falls after the procedure and can be easily reproduced by other orthopedic surgeons. It resulted in an average time to union of 6.9 months (range: 3.2 to 13.9 mo).
Parkulo et al. (Mon,) studied this question.