Thrower\u27s Exostosis of the Shoulder: A Systematic Review with a Novel Classification

Background: A variety of thrower\u27s exostoses are grouped under the term Bennett lesion, which makes understanding diagnosis and treatment difficult. Purpose: To identify all types of reported thrower\u27s and overhead athlete\u27s exostoses and categorize them into a classification system to allow a morphology-based classification. Study Design: Systematic review; Level of evidence, 4. Methods: A systematic review of all articles pertaining to Bennett lesions and thrower\u27s exostosis was performed. The classification and treatments were evaluated to describe the types, proposed causes, diagnosis, and treatment options. Results: A total of 27 studies were included in the systematic review. The anatomic locations referenced in the study demonstrated posteroinferior, posterior, and posterosuperior glenoid lesions. Aggregate radiographic data demonstrated 158 of 306 patients (52%) with a thrower\u27s exostosis of any type and location. Of these 158 patients with a radiographic lesion, 119 (75%) patients were symptomatic. The locations were posteroinferior in 110 patients (70%), directly posterior in 2 patients (1.3%), posterosuperior in 44 patients (28%), and unknown in 2 patients (1.3%). Avulsed lesions were present in 9 (5.7%) posteroinferior lesions, 0 direct posterior lesions, and 2 (1.3%) posterosuperior lesions. Treatment plans included both nonoperative and operative strategies, but operative intervention was more commonly reported for detached lesions. After operative intervention, only 61% of reported athletes returned to preinjury performance. Conclusion: Based on a comprehensive review of the literature, we identified several anatomic locations for a thrower\u27s exostosis beyond the classic Bennett lesion. We categorized the reported exostoses into a new classification system for description of location and type (subperiosteal or free fragment) of the thrower\u27s exostosis, which may be used to study future treatments. Current treatment strategies recommend that surgical treatment of thrower\u27s exostosis is considered only after exhausting nonoperative management because reported return to sport is variable after surgery. The effectiveness of excision or repair for both subperiosteal and detached lesions has not been established

PIEZO1 is downregulated in glenohumeral chondrocytes in early cuff tear arthropathy following a massive rotator cuff tear in a mouse model

Introduction: A massive rotator cuff tear (RCT) leads to glenohumeral joint destabilization and characteristic degenerative changes, termed cuff tear arthropathy (CTA). Understanding the response of articular cartilage to a massive RCT will elucidate opportunities to promote homeostasis following restoration of joint biomechanics with rotator cuff repair. Mechanically activated calcium-permeating channels, in part, modulate the response of distal femoral chondrocytes in the knee against injurious loading and inflammation. The objective of this study was to investigate PIEZO1-mediated mechanotransduction of glenohumeral articular chondrocytes in the altered biomechanical environment following RCT to ultimately identify potential therapeutic targets to attenuate cartilage degeneration after rotator cuff repair.Methods: First, we quantified mechanical susceptibility of chondrocytes in mouse humeral head cartilage ex vivo with treatments of specific chemical agonists targeting PIEZO1 and TRPV4 channels. Second, using a massive RCT mouse model, chondrocytes were assessed for mechano-vulnerability, PIEZO1 expression, and calcium signaling activity 14-week post-injury, an early stage of CTA.Results: In native humeral head chondrocytes, chemical activation of PIEZO1 (Yoda1) significantly increased chondrocyte mechanical susceptibility against impact loads, while TRPV4 activation (GSK101) significantly decreased impact-induced chondrocyte death. A massive RCT caused morphologic and histologic changes to the glenohumeral joint with decreased sphericity and characteristic bone bruising of the posterior superior quadrant of the humeral head. At early CTA, chondrocytes in RCT limbs exhibit a significantly decreased functional expression of PIEZO1 compared with uninjured or sham controls.Discussion: In contrast to the hypothesis, PIEZO1 expression and activity is not increased, but rather downregulated, after massive RCT at the early stage of cuff tear arthropathy. These results may be secondary to the decreased axial loading after glenohumeral joint decoupling in RCT limbs

Basic Hip Arthroscopy: Supine Patient Positioning and Dynamic Fluoroscopic Evaluation

Hip arthroscopy serves as both a diagnostic and therapeutic tool for the management of various conditions that afflict the hip. This article reviews the basics of hip arthroscopy by demonstrating supine patient positioning, fluoroscopic evaluation of the hip under anesthesia, and sterile preparation and draping. Careful attention to detail during the operating theater setup ensures adequate access to the various compartments of the hip to facilitate the diagnosis of disease and treatment with minimally invasive arthroscopy. Furthermore, having a routine method for patient positioning and operative setup improves patient safety, as well as operative efficiency, as the operative team becomes familiar with the surgeon's standard approach to hip arthroscopy cases

Arthroscopic Treatment of Slipped Capital Femoral Epiphysis Screw Impingement and Concomitant Hip Pathology

Impingement caused by screws used for stabilization of slipped capital femoral epiphysis can be treated arthroscopically. Although troublesome screws have traditionally been removed by open techniques, arthroscopic removal can successfully be achieved. In addition to affording the patient the benefits of minimally invasive surgery, surgeons also have the ability to arthroscopically address any concomitant hip pathology responsible for pain, including femoroacetabular impingement and labral tears

Notchplasty for the Arthroscopic Treatment of Limited Knee Extension

Knee osteoarthritis may lead to narrowing of the intercondylar notch due to osteophyte formation, thereby causing changes in native knee biomechanics. The normal close contact between the condyles and the anterior cruciate ligament (ACL) during knee extension may be compromised due to narrowing of the notch and result in ACL damage, progression of knee osteoarthritis, and loss of knee extension. Outcomes after a notchplasty procedure are well reported for ACL reconstruction in young patients. However, there remains a lack of studies evaluating this procedure in the setting of knee osteoarthritis in patients with a symptomatic loss of knee extension. The purpose of this Technical Note is to present our preferred surgical technique for the treatment of loss of knee extension in the setting of knee osteoarthritis in conjunction with osteophyte formation in the intercondylar notch

Arthroscopic Debridement of Pediatric Accessory Anterolateral Talar Facet Causing Impingement

Symptomatic subfibular and/or lateral talocalcaneal impingement in pediatric patients may result from an accessory anterolateral talar facet (AALTF). This impingement may cause pain and disability and may limit athletic performance in high-level athletes. We report the case of a 12-year-old female competitive gymnast who had refractory, lateral-sided right ankle pain for 4 months and underwent right ankle arthroscopic resection of the AALTF causing impingement. Standard medial and anterolateral portals with the addition of an accessory anterolateral-distal portal were used in conjunction with a 30° 2.7-mm-diameter arthroscope. The AALTF was resected with a combination of a shaver and a motorized rasp. Intraoperative fluoroscopy was used to verify successful debridement of the bony facet. This case illustrates that arthroscopic debridement is a technique to treat subfibular and/or talocalcaneal impingement associated with an AALTF

Arthroscopic Treatment of Bucket-Handle Labral Tear and Acetabular Fracture

Traumatic hip dislocations are associated with chondral and labral pathology as well as loose bodies that can be incarcerated in the joint. These types of injury often lead to traumatic arthritis. In some cases an osseo-labral fragment may become incarcerated in the joint that is not readily visualized preoperatively. In place of open surgery, hip arthroscopy permits a technique to remove loose bodies and repair labral tears to restore joint congruity and achieve fracture reduction and fixation

Arthroscopic Focal Subspinal Decompression and Management of Pincer-Type Femoroacetabular Impingement

Femoroacetabular impingement syndrome is a common hip pathology significantly affecting not only the intra- and extra-articular structures but also the biomechanical function of the joint. Cam and pincer bony lesions have been extensively studied. However, during recent years, other types of extra-articular impingement between the pelvic and femoral bone have been investigated. When a prominent or morphologically abnormal anterior-inferior iliac spine (AIIS) impinges repetitively on the femoral side during motion, the subspinal acetabular region becomes prominent and extends toward the intra-articular part of the joint. This results in restriction of the range of motion of the hip and pain, especially with flexion. Therefore, during hip arthroscopy, it is necessary to evaluate the subspinal region (triangular area located at 1:30 to 2:30 o'clock using the acetabular clock face system). For the correction of the acetabular bone pathology to be complete, the surgeon should focus both on the pincer and subspinal impingement lesions. This article describes our preferred technique to successfully address subspinal and pincer acetabular impingement during hip arthroscopy. The pearls and pitfalls of this technique are discussed

Basic Shoulder Arthroscopy: Lateral Decubitus Patient Positioning

Shoulder arthroscopy offers a minimally invasive surgical approach to treat a variety of shoulder pathologies. The patient can be positioned in either the lateral decubitus or the beach chair position. This note and accompanying video describe the operating room setup for shoulder arthroscopy in the lateral decubitus position, including positioning of the arms, head, and sterile preparation and draping. Appropriate lateral decubitus positioning for shoulder arthroscopy with careful attention to detail will promote ease of surgical intervention and minimize complications