Arthroscopic simulation has rapidly evolved recently with the introduction of higher-fidelity simulation models, such as virtual reality simulators, which provide trainees an environment to practice skills without causing undue harm to patients. Simulation training also offers a uniform approach to learn surgical skills with immediate feedback. The aim of this article is to review the recent research investigating the use of arthroscopy simulators in training and the teaching of surgical skills. A systematic review of the Embase, MEDLINE, and Cochrane Library databases for English-language articles published before December 2019 was conducted. The search terms included arthroscopy or arthroscopic in combination with simulation or simulator. We identified a total of 44 relevant studies involving benchtop or virtually simulated ankle, knee, shoulder, and hip arthroscopy environments. The majority of these studies demonstrated construct and transfer validity; considerably fewer studies demonstrated content and face validity. Our review indicates that there is a considerable evidence base regarding the use of arthroscopy simulators for training purposes. Further work should focus on the development of a more uniform simulator training course that can be compared with current intraoperative training in large-scale trials with long-term follow-up at tertiary centers.

Appropriate total hip arthroplasty (THA) reconstruction must simultaneously address component position, restoration of biomechanics, and soft-tissue balance. Preoperative planning for complex THA cases should include radiographic templating, a detailed case plan that contains backup implant options, and a thorough understanding of the patient's preoperative examination. Using a systematic approach to soft-tissue balancing in THA enhances the ability to intraoperatively execute the preoperative plan. In patients with preexisting deformities (e.g., dysplasia or prior surgery), increased attention to abductor function is necessary when assessing acetabular component placement and offset.

Given the relatively high prevalence of full-thickness articular cartilage lesions, including in patients who are <40 years of age, and an inability to detect some of these lesions until the time of arthroscopy, there is value in performing a single-stage cartilage procedure such as marrow stimulation (MS). While the positive outcomes of first-generation MS (namely microfracture) have been observed to drop off after 24 months in several studies, improvements have been seen when compared with preoperative conditions for lesions that are 2 to 3 cm2 in size, and MS is considered to be a procedure with technical simplicity, fairly short surgical times, and relatively low morbidity. A recent study showed that autologous chondrocyte implantation (ACI) and osteochondral allograft (OCA) transplantation remain viable treatment options for chondral defects of the knee in the setting of failed MS. Basic science principles that have been elucidated in recent years include (1) the creation of vertical walls during defect preparation, (2) an increased depth of subchondral penetration, (3) a smaller awl diameter, and (4) an increased number of subchondral perforations, which are all thought to help resolve issues of access to the mesenchymal stromal cells (MSCs) and the subchondral bone structure/overgrowth issues. Pioneering and evolving basic science and clinical studies have led to next-generation clinical applications, such as a hyaluronic acid-based scaffold (ongoing randomized controlled trial [RCT]), an atelocollagen-based gel (as described in a recently published RCT), a micronized allogeneic cartilage scaffold (as described in a recently completed prospective cohort study), and a biosynthetic hydrogel that is composed of polyethylene glycol (PEG) diacrylate and denatured fibrinogen (as described in an ongoing prospective study). This review summarizes important points for defect preparation and the recent advances in MS techniques and identifies specific scaffolding augmentation strategies (e.g., mesenchymal augmentation and scaffold stimulation [MASS]) that have the capacity to advance cartilage regeneration in light of recent laboratory and clinical studies.

Use of computer-assisted navigation (CAN) and robotic-assisted (RA) surgery in total knee arthroplasty (TKA) and unicompartmental knee arthroplasty (UKA) both necessitate the use of tracking pins rigidly fixed to the femur and tibia. Although periprosthetic fractures through tracking pin sites are rare, there is a paucity of literature on this potential complication. Therefore, the purpose of this study was to perform a systematic review of the current literature to assess the incidence and clinical outcomes of periprosthetic fractures through tracking pin sites following CAN and RA TKA and UKA. A systematic review was performed following PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) guidelines using the PubMed, MEDLINE, and Cochrane databases in April 2020. Studies were assessed for the presence of pin site fractures, fracture characteristics, and clinical outcomes. Seventeen clinical studies (5 case series, 1 cohort study, and 11 case reports) involving 29 pin-related fractures were included for review. The overall incidence ranged from 0.06% to 4.8%. The mean time from index arthroplasty to fracture was 9.5 weeks (range, 0 to 40 weeks). The majority of fractures occurred in the femoral diaphysis (59%). Nineteen fractures (66%) were displaced and 10 (34%) were nondisplaced or occult. The majority of cases were atraumatic in nature or involved minor trauma and were typically preceded by persistent leg pain. A transcortical pin trajectory, large pin diameter (>4 mm), diaphyseal fixation, multiple placement attempts, and the use of non-self-drilling, non-self-tapping pins were the most commonly reported risk factors for pin-related periprosthetic fractures following CAN or RA TKA. Surgeons should maintain a high index of suspicion for pin-related fractures in patients with ongoing leg or thigh pain after CAN or RA TKA in order to avoid fracture displacement and additional morbidity. As CAN and RA TKA have unique complication risks, the debate regarding the value of technology-assisted TKA and its cost-effectiveness continues. Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Cold therapy, also known as cryotherapy, includes the use of bagged ice, ice packs, compressive cryotherapy devices, or whole-body cryotherapy chambers. Cryotherapy is commonly used in postoperative care for both arthroscopic and open orthopaedic procedures. Cryotherapy is associated with an analgesic effect caused by microvasculature alterations that decrease the production of inflammatory mediators, decrease local edema, disrupt the overall inflammatory response, and reduce nerve conduction velocity. Postoperative cryotherapy using bagged ice, ice packs, or continuous cryotherapy devices reduced visual analog scale pain scores and analgesic consumption in approximately half of research studies in which these outcomes were compared with no cryotherapy (11 [44%] of 25 studies on pain and 11 [48%] of 23 studies on opioids). However, an effect was less frequently reported for increasing range of motion (3 [19%] of 16) or decreasing swelling (2 [22%] of 9). Continuous cryotherapy devices demonstrated the best outcome in orthopaedic patients after knee arthroscopy procedures, compared with all other procedures and body locations, in terms of showing a significant reduction in pain, swelling, and analgesic consumption and increase in range of motion, compared with bagged ice or ice packs. There is no consensus as to whether the use of continuous cryotherapy devices leads to superior outcomes when compared with treatment with bagged ice or ice packs. However, complications from cryotherapy, including skin irritation, frostbite, perniosis, and peripheral nerve injuries, can be avoided through patient education and reducing the duration of application. Future Level-I or II studies are needed to compare both the clinical and cost benefits of continuous cryotherapy devices to bagged ice or ice pack treatment before continuous cryotherapy devices can be recommended as a standard of care in orthopaedic surgery following injury or surgery.

Synovial chondromatosis (SC) of the ankle is a rare disorder in which metaplastic proliferation of synovia, tendon sheaths, and/or bursae leads to the formation of loose cartilaginous bodies within the joint space. While SC itself is a benign condition, its sequelae can be chronic and debilitating if left untreated, or if there is postoperative recurrence. Arthritic degeneration and malignant transformation to chondrosarcoma are among the more serious complications in the natural history of the disease; the latter occurs in approximately 5% of cases. We performed a systematic review of the literature on the arthroscopic management of ankle SC in order to better understand recurrence patterns and suggest an alternative approach to open arthrotomy. Using predetermined inclusion and exclusion criteria, the PubMed and Embase databases were searched for relevant articles related to arthroscopic surgical management of patients with confirmed SC of the ankle. Article selection and data abstraction were performed in 3 steps by 3 independent reviewers. The initial search retrieved 116 articles, of which 15 were included. Those studies included 22 patients (14 to 63 years of age; 77% male) who were followed for a mean of 27 months (range, 8 weeks to 12 years) postoperatively. The cases represented a mix of primary and secondary SC etiologies, and almost entirely stage-III disease. Arthroscopic synovectomy with excision of loose bodies was a consistent feature of treatment, and bursectomy, debridement of osteochondral lesions or involved tendons, and osteophyte resection were performed as indicated. All but 1 case employed an anterior approach including anteromedial and anterolateral portals, and in several cases a 4-portal technique was used, which was subsequently proposed as a necessary approach for the definitive treatment of ankle SC. On the basis of the available data, complication and recurrence rates following arthroscopic management were very low. A growing pool of evidence is emerging to suggest favorable outcomes for arthroscopic treatment of SC of the ankle joint. However, more data on patient and surgical variables, as well as comparative studies with longer follow-up, are needed in order to draw definitive conclusions. Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Oncologic sacrectomy is used in the curative treatment of patients with primary sacral malignancies or select locally invasive visceral malignancies. A systematic surgical approach involves preoperative imaging, diagnosis, and multidisciplinary surgical execution. Close collaboration with pediatric, medical, and radiation oncology colleagues is often necessary to individualize treatment plans.

New knowledge about the molecular biology of fracture-healing provides opportunities for intervention and reduction of risk for specific phases that are affected by disease and medications. Modifiable and nonmodifiable risk factors can prolong healing, and the informed clinician should optimize each patient to provide the best chance for union. Techniques to monitor progression of fracture-healing have not changed substantially over time; new objective modalities are needed.

There remains a dearth of research on and general knowledge with regard to materials used for wound closure and soft-tissue repair and approximation. Critical suture properties include physical configuration, fluid absorption and capillarity, caliber or diameter, tensile strength, torsion, absorbability, elasticity, plasticity, memory, coefficient of friction, and knot security. The optimal ranges of each of these characteristics remain undefined for most sutures and indications. Needle types and basic design characteristics affect suture passage and require further consideration with regard to specific suture-needle selection. Suture must perform its intended purpose with a minimum of undesirable reaction and infectious potential, adequate duration of efficacy, and adequate strength. However, stronger, or high tensile strength, suture is not always better because of the requisite increase in suture caliber as well as the potential for inadvertent tissue strangulation, possibly increasing inflammatory reactivity. Sometimes, we seek stable, watertight fascial closure; occasionally, strong and durable tendon repair; and other times, gentle, cosmetically friendly, skin eversion and opposition. A variety of common suture types differ in these critical characteristics and may be optimally utilized for contrasting, but sometimes overlapping, indications.

Infection is a devastating complication in anterior cruciate ligament reconstruction (ACLR) surgery. Given the rarity of infection, pooling individual studies via meta-analysis can allow more meaningful evaluation of factors influencing infection rates. We aimed to determine the relationship of graft type and vancomycin graft presoaking to bacterial infection rates following ACLR. A systematic literature search was conducted on PubMed, Ovid MEDLINE, Embase, and CENTRAL (Cochrane Register of Controlled Trials). Included articles were those reporting on primary arthroscopic or open ACLR procedures, using hamstring (HT) or bone-patellar tendon-bone (BPTB) autografts or allografts of any type, with regard to the outcome of infection (deep infection or septic arthritis). Meta-analyses were performed to estimate the overall infection rates in ACLR surgery according to graft type and to examine the effect of presoaking grafts in vancomycin on infection rates. We identified 306 bacterial infections in 68,453 grafts across 198 studies. The overall estimated ACL graft infection rate in our meta-analysis was 0.9% (95% confidence interval [CI] = 0.8% to 1.0%). HT autografts were associated with a higher infection rate (1.1%, CI = 0.9% to 1.2%) than BPTB autografts (0.7%, CI = 0.6% to 0.9%) and allografts (0.5%, CI = 0.4% to 0.8%) (Q = 15.58, p < 0.001). Presoaking HT autografts in vancomycin reduced infection rates to 0.1% (CI = 0.0% to 0.4%) (Q = 10.62, p = 0.001). Infection following ACLR remains a rare but serious complication. HT autografts are associated with higher infection rates than other graft types. Presoaking HT autografts in vancomycin reduces infection rates by an estimated tenfold. Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.