Incidence and risk factors for aseptic baseplate loosening of reverse total shoulder arthroplasty.

BACKGROUND: Aseptic glenoid baseplate loosening (AGBL) is a catastrophic complication after reverse total shoulder arthroplasty (RTSA). Our goals were to determine the incidence of AGBL in patients who underwent RTSA and identify risk factors for AGBL after RTSA. METHODS: We analyzed 202 shoulders that underwent primary or revision RTSA using 1 implant system and evaluated baseplate loosening at a minimum 2-year follow-up. The associations between AGBL and the following variables were investigated: patient age, sex, primary vs. revision RTSA, scapular notching, use of bone graft, and type of baseplate screw fixation. RESULTS: AGBL occurred in 6 shoulders (3.0%). The incidence of AGBL after revision RTSA (10%) was significantly higher than that after primary RTSA (1.2%; P = .014). There were significant associations between AGBL and the use of bone graft and the use of nonlocking screws. Scapular notching, glenosphere center-of-rotation offset, patient age, and sex were not associated with AGBL. Multiple logistic regression analysis showed that the use of all peripheral nonlocking 3.5-mm screws (odds ratio, 10.6; 95% confidence interval, 1.1- 39) and the use of bone graft (odds ratio, 7.5; 95% confidence interval, 1.9-30) were independent risk factors for AGBL. CONCLUSIONS: The rate of baseplate failure after primary RTSA is low (1.2%) but is significantly higher after revision RTSA (10%). Major risk factors for baseplate failure are the use of all 3.5-mm nonlocking screws for peripheral baseplate fixation and the use of a bone graft to address deficiencies in bony support beneath the baseplate.

Extra-Axial Chordoma of the Hand.

Chordomas are low-grade malignant tumors that are locally aggressive and have the potential to metastasize. They most often occur in the sacrococcygeal and spheno-occipital portions of the vertebral column. Morphologically similar tumors have been found outside the axial skeleton and are referred to as extra-axial chordomas. Several case reports have described the radiologic, microscopic, and immunologic profiles of these tumors and their similarities to axial chordomas. The authors report a 24-year-old man who presented with a mass in his left hand and underwent surgical excision. Specimens stained positive for pancytokeratin, S100, and brachyury. Brachyury is a protein that is present during embryogenesis and is expressed by chordomas. This is the first report of an extra-axial chordoma within the interosseous muscle compartment of the hand in a young patient.

Sarcoma Happens: A Reminder for Arthroscopic Surgeons.

Primary intra-articular sarcomas are rare and present with nonspecific symptoms such as pain or swelling. Due to nonspecific symptoms, patients may undergo routine diagnostic arthroscopy, which ultimately leads to sarcoma diagnosis. Here we present four patients with intra-articular sarcomas of the knee diagnosed after arthroscopy. The goal of this study is to highlight the importance of including malignant bone and soft-tissue sarcomas in the differential diagnosis of patients with nonspecific knee symptoms. A case series was developed from a retrospective review of prospectively collected data from our institution's orthopedic oncology database. Patients who underwent arthroscopic procedures on the knee and who were diagnosed with intra-articular sarcomas postoperatively from 2014 to 2019 were identified. All patients underwent diagnosis, staging, and multidisciplinary evaluation and treatment. Clinical characteristics, oncologic considerations, and surgical outcomes are described. Four patients with intra-articular sarcomas of the knee diagnosed after arthroscopy for non-oncologic concerns were identified: two synovial sarcomas, one Ewing sarcoma of bone, and one osteosarcoma. All surgical plans and treatment options were significantly affected by the previous arthroscopic procedures. One patient underwent above-the-knee amputation; one patient underwent extra-articular wide resection of the knee, including portal sites with distal femur/total knee reconstruction; one patient underwent rotationplasty, and one patient was treated with therapeutic radiation (no surgery). All patients received chemotherapy. Although intra-articular sarcomas are rare, orthopaedic surgeons must remain vigilant when proceeding with arthroscopic procedures if the clinical history, physical exam, and imaging findings are not perfectly aligned.

Conversion of anatomic total shoulder arthroplasty to reverse shoulder arthroplasty using a unique hybrid glenoid component: technique and preliminary results.

Background: Degenerative arthritis of the shoulder is a common condition that is successfully treated with anatomic total shoulder arthroplasty (TSA). Rotator cuff disease has evolved as a leading cause of failure of anatomic TSA, requiring revision to reverse shoulder arthroplasty (RSA). This revision procedure can be extremely complex, particularly if removal of a well-fixed glenoid component is necessary. This case series outlines the technique and preliminary clinical results of conversion of anatomic TSA to RSA utilizing both modular humeral and hybrid glenoid components. Methods: From July 2017 to December 2019, the senior author (PMC) performed 84 consecutive anatomic TSA procedures utilizing a modular humeral arthroplasty system and a unique hybrid glenoid component. Three cases (3/84, or 3.6%) required conversion from anatomic TSA to RSA because of postoperative traumatic rotator cuff failure. All modular revision cases were performed without humeral stem removal and with utilization of the existing, well-fixed hybrid glenoid central titanium peg as the foundation for glenoid component revision. Preoperative and postoperative American Shoulder and Elbow Surgeons scores, visual analog scale pain scores, forward flexion, and patient satisfaction were analyzed in this modular revision group. In addition, several perioperative variables including operative time, blood loss, and length of stay were compared between this modular revision group and a nonmodular anatomic TSA to RSA revision comparative cohort. Results: At an average follow-up of 24 months, average active forward flexion, postoperative American Shoulder and Elbow Surgeons scores, and visual analog scale pain scores improved significantly compared with preoperative scores in the modular revision group. All three patients were satisfied with their outcome. The average total operative time (109 minutes vs. 154 minutes, P = .02), blood loss (183 cc vs. 500 cc, P = .08), and length of hospital stay (26.3 hours vs. 36.6 hours P < .05) were lower in the modular revision group than those in a nonmodular revision cohort. Conclusion: Revision of anatomic TSA to RSA utilizing a modular humeral system and a convertible hybrid glenoid component that does not require removal of a well-fixed central titanium peg which serves as the foundation for glenoid component revision was performed efficiently, safely, and successfully in three cases. This technique results in significantly improved clinical outcomes when revision to RSA is needed while potentially decreasing perioperative complications in the revision setting.

Sagittal plane alignment affects the strength of pin fixation in supracondylar humerus fractures.

ABSTRACT: Closed reduction with percutaneous pin fixation is commonly used to treat pediatric supracondylar humerus fractures. Various pin configurations of varying biomechanical strength have been described. However, to our knowledge, no biomechanical study has focused on pin alignment in the sagittal plane. Our goal was to compare the stability of fixation using 3 different pin constructs: 3 lateral pins diverging in the coronal plane but parallel in the sagittal plane (3LDP), 3 lateral pins diverging in the coronal and sagittal planes (3LDD), and 2 crossed pins (1 medial and 1 lateral).Transverse fractures were made through the olecranon fossa of 48 synthetic humeri, which were then reduced and pinned in the 3LDP, 3LDD, and crossed-pin configurations (16 specimens per group) using 1.6-mm Kirschner wires. The sagittal plane pin spread was significantly greater in the 3LDD group than in the 3LDP group, whereas we found no difference in the coronal plane. Sagittal extension testing was performed from 0° to 20° at 1°/s for 10 cycles using a mechanical torque stand. The torque required to extend the distal fragment 20° from neutral was compared between groups using one-way analysis of variance with multiple comparison post-hoc analysis. P values ≤.05 were considered significant.The 3LDD configuration was more stable than the 3LDP and crossed-pin configurations. The mean torque required to displace the pinned fractures was 5.7 Nm in the 3LDD group versus 4.1 Nm in the 3LDP group and 3.7 Nm in the crossed-pin group (both, P < .01). We found no difference in stability between the 3LDP and crossed-pin groups (P = .45).In a synthetic biomechanical model of supracondylar humerus fracture, sagittal alignment influenced pin construct stability, and greater pin spread in the sagittal plane increased construct stability when using 3 lateral pins. The lateral pin configurations were superior in stability to the crossed-pin configuration.Level of Evidence: Level V.

Diabetes is an independent risk factor for infection after non-arthroplasty shoulder surgery: a national database study.

OBJECTIVES: Diabetes has been associated with poor healing and prior literature has shown worse functional outcomes in diabetic patients undergoing both open and arthroscopic shoulder surgery. However, the effects of diabetes on perioperative complications for patients undergoing non-arthroplasty type shoulder procedures are not well defined. The purpose of this study was to analyze the effects of diabetes on 30-day complications following non-arthroplasty shoulder surgery. METHODS: The American College of Surgeons National Surgical Quality Improvement Program was used to identify patients who underwent open and arthroscopic shoulder procedures (excluding arthroplasty) from 2011 to 2018. Diabetic patients were identified and compared to a non-diabetic cohort. Demographic data and postoperative complications within 30 days were analyzed. Multivariable regression was used to determine the effect of diabetes on shoulder surgery. RESULTS: We identified 99,970 patients who underwent shoulder surgery in our cohort and 13.9% (13,857 patients) of these patients were diabetics. Within the diabetic cohort, 4,394 (31.7%) were insulin dependent. Diabetics were more likely to be older, female, and have a higher body mass index (P < 0.01). Diabetics had a higher rate of associated medial comorbidities (P < 0.05). Diabetics were less likely to be smokers and on average had shorter surgeries (P < 0.05). Univariate analysis showed that diabetes was associated with increased risk for infectious and other major and minor complications; however, multivariate regression revealed that diabetes was only independently associated with infection (OR 1.33, P = 0.38). CONCLUSION: While diabetes is associated with increased likelihood of infection following shoulder surgery, absent commonly associated comorbidities, they are not at increased risk for other 30-day postoperative complications.

Toileting ability of patients after primary reverse total shoulder arthroplasty.

BACKGROUND: This study aimed to determine the toileting ability (TA) of patients undergoing primary reverse total shoulder arthroplasty (RTSA) and identify factors associated with TA postoperatively. METHODS: A questionnaire regarding toileting was administered to 119 patients who underwent primary RTSA with a minimum 1-year follow-up. Patients were separated into 2 groups based on whether the arm that underwent RTSA was the one used for toileting (study group, n = 74) or not (control group, n = 45). Patient-reported TA was calculated both before and after RTSA. Multivariate analysis was performed to identify factors associated with TA postoperatively. RESULTS: Impairment in TA before RTSA was higher in the study group and affected almost three-quarters of the patients (72%). In the study group, primary RTSA resulted in a statistically significant improvement in TA (P < .001), and no difference in TA was found between groups after RTSA (P = .076). Postoperatively, 92% of the patients in the study group were able to manage toileting with the involved extremity (54% without difficulty and 38% with some degree of difficulty). Only 1 patient (1.3%) was totally unable to manage toileting with either arm postoperatively. The patients at risk of toileting difficulties postoperatively were those who had preoperative toileting difficulties and lower postoperative internal rotation range of motion. CONCLUSIONS: Over 90% of patients can manage toileting after primary RTSA, and total toileting inability is rare after the procedure (1.3%). Patients should be counseled that after primary RTSA, they have a high probability of being able to manage toileting with independence even if it is with some difficulty.

Patient Positioning in Shoulder Arthroscopy: Which is Best?

When performing diagnostic and surgical arthroscopic procedures on the shoulder, the importance of patient positioning cannot be understated. The optimum patient positioning for shoulder arthroscopy should enhance intraoperative joint visualization and surgical accessibility while minimizing potential perioperative risk to the patient. Most shoulder arthroscopy procedures can be reliably performed with the patient either in the lateral decubitus (LD) or beach chair (BC) position. Although patient positioning for shoulder arthroscopy has been subject of controversy, there is no conclusive evidence to suggest superiority of one position versus another. Each position offers advantages and disadvantages and surgeon's experience and training are pivotal on selecting one position versus another. Regardless of the position, a proper positioning of the patient should provide adequate access to the joint while minimizing complications. The purpose of this review is to summarize setup and technical aspects, the advantages and disadvantages, and the possible complications of the LD and BC positions in shoulder arthroscopy.

Incidence of clinically evident isolated axillary nerve injury in 869 primary anatomic and reverse total shoulder arthroplasties without routine identification of the axillary nerve.

BACKGROUND: It has been suggested that, during primary shoulder arthroplasty, surgeons should identify the axillary nerve through direct visualization, palpation, or the "tug test" to prevent iatrogenic nerve injury. Our goal was to document the rate of isolated axillary nerve injury (IANI) in patients who had undergone primary anatomic total shoulder arthroplasty (TSA) or reverse total shoulder arthroplasty (RTSA) without routine identification of the axillary nerve. METHODS: Data on 869 cases of primary shoulder arthroplasty (338 TSAs and 531 RTSAs) performed by 1 surgeon between 2003 and 2017 were reviewed. Neither the tug test nor identification of the axillary nerve through palpation or visualization was used in any case. The primary outcome was new IANI documented within 3 months after arthroplasty. The frequency of IANI was summarized using point estimates and 95% confidence intervals (CIs). RESULTS: Six cases met the criteria for IANI. The overall incidence of IANI was 0.7% (95% CI, 0.3%-1.4%). The incidence of IANI was 0.3% (95% CI, 0%-1.6%) after TSA and 0.9% (95% CI, 0.3%-2.1%) after RTSA. All IANIs were cases of neurapraxia, and all patients had experienced complete neurologic recovery at last follow-up. CONCLUSION: Complete, permanent IANI resulting from direct surgical trauma during primary shoulder arthroplasty can be avoided without using the tug test or routine identification of the nerve. A low incidence of partial temporary IANI can be expected, which may be related to indirect traction injuries.

Driving after Upper or Lower Extremity Orthopaedic Surgery.

Orthopaedic procedures can affect patients' ability to perform activities of daily living, such as driving automobiles or other vehicles that require coordinated use of the upper and lower extremities. Many variables affect the time needed before a patient can drive competently after undergoing orthopaedic surgery to the extremities. These variables include whether the patient underwent upper or lower extremity surgery, the country in which the patient resides, whether the right or left lower extremity is involved, whether the dominant arm is involved, whether the extremity is in a cast or brace, whether the patient has adequate strength to control the steering wheel, and whether the patient is taking pain medication. The type and complexity of the procedure also influence the speed of return of driving ability. Few studies provide definitive data on driving ability after upper or lower extremity surgery. Patients should be counseled not to drive until they can control the steering wheel and the pedals competently and can drive well enough to prevent further harm to themselves or to others. This review discusses the limited recommendations in the literature regarding driving motorized vehicles after upper or lower extremity orthopaedic surgery.