Osteology: The 3 bones that comprise the elbow joint (distal humerus, proximal ulna, and proximal radius) allow it to function as a trochoginglymus joint, providing both flexion/extension as well as pronation-supination. Distal humerus: transitions from the shaft to the medial and lateral columns, which support the articular surface (Figure 1-1) Lateral column Lateral supracondylar ridge: attachment of brachioradialis (BR) and extensor carpi radialis longus anteriorly and triceps posteriorly (Figure 1-2) Avascular zone between BR and triceps marks the lateral column for surgical exposure Lateral epicondyle: attachment of common extensor-supinator tendon and lateral ulnar collateral ligament (LUCL) posteriorly Tendinitis of extensor carpi brachialis brevis (deep in common extensor mass) is cause of lateral epicondylitis 1 (Figure 1-3) Lateral epicondyle debridement: must stay anterior to LUCL to avoid creating posterior rotatory instability Medial column The medial supracondylar ridge is more narrow than lateral, thus more prone to fracture The medial epicondyle is more prominent than the lateral, serves as attachment of medial ulnar collateral ligament and flexor-pronator mass Figure 1-1 (A) The articular surfaces of the elbow joint. Note the anterior capsular attachment to the coronoid. This also demonstrates the more anterior/distal projection of the medial trochlea, which creates the valgus carrying angle in elbow extension. (B) Osteology of the distal humerus. Note the coronoid fossa and olecranon fossa anteriorly and posteriorly, respectively. The lateral view demonstrates the anterior angulation of the distal humerus to aid in full flexion. https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9781003524243/e2a244c3-6295-4c82-b6fb-c3937c885478/content/fig1-1.jpg" xmlns:xlink="https://www.w3.org/1999/xlink"/> Supracondylar process is seen in 1% to 3% of patients, attachment for ligament of Struthers may cause median nerve impingement (pronator syndrome) 2 Articular surfaces: angulated 30 degrees anteriorly, matches 30 degrees posterior angulation of greater sigmoid notch of the ulna Trochlea: articulates with greater sigmoid notch of ulna, 300 degrees covered with articular cartilage, medial portion is more distal than lateral, bordered anterosuperiorly by coronoid fossa and posterosuperiorly by olecranon fossa Figure 1-2 Superficial view of the lateral humerus demonstrates the fascial layer of the common extensor mass, the anconeus, and the triceps at the top of the figure. https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9781003524243/e2a244c3-6295-4c82-b6fb-c3937c885478/content/fig1-2.jpg" xmlns:xlink="https://www.w3.org/1999/xlink"/> Figure 1-3 The superficial layer of the common extensor mass is reflected to demonstrate the deeper layer containing the tendinous insertion of the extensor carpi radialis brevis. This is the tendon affected by lateral epicondylitis at the tendon's insertion to the lateral epicondyle. https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9781003524243/e2a244c3-6295-4c82-b6fb-c3937c885478/content/fig1-3.jpg" xmlns:xlink="https://www.w3.org/1999/xlink"/> Capitellum: articulates with radial head, spheroidal in shape, thick cartilage layer (approximately 2 mm) anteriorly Proximal ulna: subcutaneous along posteromedial aspect of forearm (Figure 1-4) Olecranon process: posterior and proximal portion of the ulna, serves as an attachment site for the triceps tendon Coronoid process: anterior portion of ulnohumeral articulation, serves as a buttress to maintain anterior stability of the joint, attachment site of the brachialis tendon and anterior joint capsule Greater sigmoid notch: cartilage-covered grooved surface that articulates with the trochlea of the distal humerus and allows flexion and extension of the joint, 30 degrees of posterior angulation to match that of the trochlea Lesser sigmoid notch: distal-lateral to the greater sigmoid notch, small cartilage-covered groove that articulates the ulna with the radial head Can serve as an alignment landmark for reconstruction or replacement of radial head fractures 3 Supinator crest: raised area distal and posterior to lesser sigmoid notch, attachment site of lateral collateral ligament and important landmark for reconstruction of this structure Proximal radius: primary role is to allow pronation and supination of the elbow Radial head: Central depression that articulates with the capitellum, the radial head should always point at the capitellum on x-ray at all ranges of motion. There is a 240-degree rim of articular cartilage around the radial head that articulates with the Figure 1-4 Osteology of the proximal ulna. https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9781003524243/e2a244c3-6295-4c82-b6fb-c3937c885478/content/fig1-4.jpg" xmlns:xlink="https://www.w3.org/1999/xlink"/> lesser sigmoid notch (proximal radioulnar joint); the remaining 120 degrees does not articulate and thus is a safe zone for hardware placement. The safe zone can be identified using distal radius landmarks such as the arc between the radial styloid and Lister tubercle. 4 Radial tuberosity: medial aspect of the proximal radius and serves as the attachment site of the distal biceps tendon Radial neck: distal to the radial head, transition point to the shaft, has 15 degrees of valgus angulation that should be taken into account during radial head replacement 3

BACKGROUND:For anatomic total arthroscopic repair, cementless humeral fixation has recently gained popularity. However, few studies have compared clinical, radiographic, and patient-reported outcomes between cemented and press-fit humeral fixation, and none have performed follow-up for longer than 5 years. In this study, we compared long-term postoperative outcomes in patients receiving a cemented versus press-fit humeral stem anatomic arthroscopic repair.METHODS:This study retrospectively analyzed 169 shoulders that required primary anatomic total shoulder arthroplasty (aTSA). Shoulders were stratified by humeral stem fixation technique: cementation or press-fit. Data were collected pre- and postoperatively. Primary outcome measures included range of motion, patient reported outcomes, and radiographic measures.RESULTS:One hundred thirty-eight cemented humeral stems and 31 press-fit stems were included. Significant improvements in range of motion were seen in all aTSA patients with no significant differences between final cemented and press-fit stems (forward elevation: P=0.12, external rotation: P=0.60, and internal rotation: P=0.77). Patient reported outcome metrics also exhibited sustained improvement through final follow-up. However, at final follow-up, the press-fit stem cohort had significantly better overall scores when compared to the cemented cohort (visual analog score: P=0.04, American Shoulder and Elbow Surgeon Score: P<0.01, Simple Shoulder Test score: P=0.03). Humeral radiolucency was noted in two cemented implants and one press-fit implant. No significant differences in implant survival were observed between the two cohorts (P=0.75).CONCLUSIONS:In this series, we found that irrespective of humeral fixation technique, aTSA significantly improves shoulder function. However, within this cohort, press-fit stems provided significantly better outcomes than cemented stems in terms of patient reported outcome scores. Level of evidence: III.

BACKGROUND:In the past decade, the number of anatomic total shoulder arthroplasty (aTSA) procedures has steadily increased. Patients over 65 years of age comprise the vast majority of recipients, and outcomes have been well documented; however, patients are opting for definitive surgical treatment at younger ages.We aim to report on the effects of age on the long-term clinical outcomes following aTSA.METHODS:Among the patients who underwent TSA, 119 shoulders were retrospectively analyzed. Preoperative and postoperative clinical outcome data were collected. Linear regression analysis (univariate and multivariate) was conducted to evaluate the associations of clinical outcomes with age. Kaplan-Meier curves and Cox regression analyses were performed to evaluate implant survival.RESULTS:At final follow-up, patients of all ages undergoing aTSA experienced significant and sustained improvements in all primary outcome measures compared with preoperative values. Based on multivariate analysis, age at the time of surgery was a significant predictor of postoperative outcomes. Excellent implant survival was observed over the course of this study, and Cox regression survival analysis indicated age and sex to not be associated with an increased risk of implant failure.CONCLUSIONS:When controlling for sex and follow-up duration, older age was associated with significantly better patient-reported outcome measures. Despite this difference, we noted no significant effects on range of motion or implant survival. Level of evidence: IV.

Background: The short-term results of total shoulder arthroplasty with an inlay glenoid component performed by a single surgeon in patients with glenoid bone loss have previously been reported. The purpose of this study was to investigate the mid-to long-term clinical and radiographic outcomes of these patients.Methods: We identified a cohort of patients who underwent total shoulder arthroplasty with an inlay glenoid component performed by a single surgeon between 2010 and 2019 for severe glenoid dysplasia and/or glenoid bone loss. Patients with a minimum of 2 years' follow-up were evaluated regarding preoperative and postoperative range of motion, radiographic findings, visual analog scale pain scores, and Single Assessment Numeric Evaluation scores.Results: Overall, 39 shoulders in 33 patients were treated with an inlay glenoid component for severe glenoid bone loss. Four patients were lost to follow-up, and 1 patient died with a well-functioning implant in place. The final cohort included 34 shoulders in 28 patients (46.4% female patients [13 of 28] and 53.6% male patients [15 of 28]) with a mean age of 66.9 years (range, 58-81 years) and mean follow-up period of 68.3 months. Of the 34 cases, 5 were revision cases. One patient died following 2-year follow-up. Of the shoulders, 10 were classified as Walch type A2, 4 were classified as Walch type B3, and 15 were classified as Walch type C; 5 shoulders were unable to be classified. We observed statistically significant increases in range of motion (forward elevation, 38.1 degrees [P < .001]; external rotation, 18.8 degrees [P < .001]) and improvement in the Single Assessment Numeric Evaluation score (from 26.6 to 81.0, P < .001). Two patients underwent conversion to reverse shoulder arthroplasty at 2.2 and 1.7 years postoperatively.Conclusion: Inlay glenoid components provide a low rate of revision and improved clinical and functional outcomes at mid-to long-term follow-up.Level of evidence: Level IV; Case Series; Treatment Study (c) 2022 Journal of Shoulder and Elbow Surgery Board of Trustees. All rights reserved.

BACKGROUND:The purpose of this study was to determine patient-specific risk factors and clinical intervention rates for abnormal postoperative Chem-7 panels in shoulder arthroplasty patients.METHODS:Retrospectively, all primary anatomic total (aTSA) and reverse shoulder (RTSA) arthroplasties (between 2007-2013) performed at a single institution were identified. All patients underwent routine preoperative and postoperative day one (POD1) chemistry panels. Each clinically significant component of the Chem-7 panel was independently evaluated using a multivariate analysis to identify risk factors for abnormal results. Associated clinical intervention rates were also calculated.RESULTS:Data from 1,012 patients (248 RTSA; 764 aTSA) was analyzed. 5.4% of patients had at least one preoperative abnormal chemistry result. On multivariate analysis, patients with abnormal preoperative Chem-7 labs and a history of renal disease had significantly increased risk for abnormal POD1 labs (P<0.001). Although 25.6% (259/1,012) of patients had at least one abnormal POD1 lab result, the total postoperative clinical intervention rate was 15.1% (39/259).CONCLUSION:Renal disease and a preoperative abnormal chemistry result are important risk factors for abnormal postoperative Chem-7. Optimizing renal status and correcting abnormal blood chemistry results preoperatively may reduce the incidence of abnormal postoperative chemistry results.

BACKGROUND:Glenoid bone loss and severe retroversion can pose difficulties when implanting a glenoid component for total shoulder arthroplasty for primary osteoarthritis. Mini-glenoid implants may be useful in the setting of severe glenoid wear in which a standard pegged glenoid component cannot be placed. MATERIALS AND METHODS:This study is a retrospective review, performed over a 3-year period, of patients who received a total shoulder arthroplasty using an inset mini-glenoid in the setting of severe glenoid dysplasia and/or medial glenoid bone loss. We identified patients with a minimum of 2 years' follow-up and evaluated preoperative and postoperative range of motion, visual analog scale scores, Single Assessment Numeric Evaluation scores, complications, and patient satisfaction. RESULTS:Seven patients (4 female and 3 male patients; 9 shoulders) with a mean age of 66 years were treated with the described procedure and had a mean follow-up of 34 months. There were 6 primary arthroplasties and 3 revision cases. Four shoulders were classified as Walch type A2 glenoids, 2 were classified as Walch type C, and 3 were unable to be classified. There was a statistically significant increase in range of motion (forward elevation, 48°; external rotation, 14°), decrease in pain scores (8 points to 1 point), and improvement in Single Assessment Numeric Evaluation scores (31.7% to 89.4%). The mean patient satisfaction score was 8.6 points on a 10-point scale. CONCLUSION:At 2-year follow-up, total shoulder arthroplasty with a mini-glenoid component can offer adequate pain relief and functional results in the setting of glenoid bone loss or severe retroversion.