Benign paroxysmal positional vertigo (BPPV) is characterized by brief episodes of vertigo triggered by changes in head position caused by the displacement of otoliths from the utricle to the semicircular canals, particularly the posterior canal. This study explored the potential link between BPPV, the patient\'s preexisting conditions, and surgery-related factors including surgical positioning, duration of the procedure, exposure to vibratory forces, and anesthesia effects. This report presents two cases of BPPV following major joint replacement surgery. The first case involved a 65-year-old male with a history of diet-controlled diabetes who had undergone right-sided total hip replacement. The second case was that of a 60-year-old female with a history of osteoporosis managed with bisphosphonate therapy and left-sided knee replacement. Both patients developed vertigo symptoms one day postoperatively and were diagnosed with BPPV. In both cases, the Dix-Hallpike test confirmed the right-sided posterior canal BPPV diagnosis, and the patients were successfully treated using the Epley maneuver. Notably, there was no recurrence of vertigo at the four-week follow-up. These cases highlight the importance of considering BPPV in patients presenting with vertigo symptoms after joint replacement surgery, especially in the presence of comorbidities like diabetes and osteoporosis which possibly increase susceptibility to BPPV. This article presents two cases of benign paroxysmal positional vertigo (BPPV) following non-otologic surgery. It explores the pathophysiological mechanism underlying BPPV after such surgeries and also discusses the diagnosis and treatment approaches. This underscores the need for prompt diagnosis and treatment of BPPV to improve postoperative outcomes.

UNASSIGNED: This case report demonstrates a virtual hybrid hospital-at-home program can provide inpatient-level postoperative and rehabilitative care after total knee arthroplasty to a medically complex patient in the comfort of their own home.
UNASSIGNED: Advanced Care at Home combines virtual providers with in-home care delivery. We report a case of virtual postoperative and rehabilitative care in a medically complex patient who underwent a total knee arthroplasty. This new model of care delivery allows effective patient-provider communication and meets patient needs in the postoperative period.

Osteoarthritis (OA) is a degenerative and progressive joint disease. When all three compartments are involved, end-stage OA is treated with a total knee arthroplasty (TKA). Unicompartmental knee arthroplasty (UKA) is a primary treatment for isolated osteoarthritis. UKA has a quicker recovery time than TKA, as well as less morbidity and more tissue sparing. At the time of surgery, 17% of patients have a tricompartmental disease and most patients with a Kellegren-Lawrence grade >3 have an intact anterior cruciate ligament (ACL). Conventional TKA sacrifices the ACL. Patients with concurrent medial and lateral osteoarthritis and a functional ACL may receive a primary bi-unicondylar arthroplasty. Combined partial knee arthroplasty (CPKA) is an established practice either in bicompartmental femoro-tibial OA or in OA progression after UKA, with the addition of another UKA. A conversion of a lateral UKA to a tricompartmental joint replacement has been reported in the literature. In our case report, we describe a one-stage hypoallergenic tricompartmental UKA, with improved clinical score and no sign of early failure at the last follow-up.

Coccidioidomycosis is a fungal infection endemic to certain regions of the Americas. In some cases, the organism may infect the musculoskeletal system, resulting in a prosthetic joint infection (PJI). Due to its difficulty in diagnosis, treatment of coccidioidomycosis in PJI is often delayed. Furthermore, with limited number of case reports, a standard of care in treatment has yet to be established. We present 2 cases of coccidioidomycosis PJI, the extensive evaluation that led to the diagnosis, and the treatment provided. This report highlights the natural progression of coccidioidomycosis in a prosthetic joint, the diagnostic features including histology, advanced imaging, and final treatment administered.

BACKGROUND: Neuroarthropathy of the knee or Charcot knee, leading to chronic joint destruction, is a rare disease that is difficult to diagnose. The treatment of this condition is difficult and controversial.
METHODS: A 74-year-old Asian woman has had bilateral knee pain for 22 years and deformity for 10 years, which has been aggravating for 2 months. Physical examination showed bilateral knee varus deformity greater than 15°, and -20 to 90° range of motion. X-ray revealed bilateral varus deformity with massive free body hyperplasia. Combined with medical history as syringomyelia, the patient was diagnosed with bilateral Charcot knees and bilateral joint replacements were performed using Legacy Constrained Condylar Knee prostheses (LCCK; Zimmer, USA). The patient reported satisfactory treatment outcomes, pain relief, and improved range of motion in both knees, without postoperative complications or prosthesis loosening at 2 year after operation.
CONCLUSIONS: Total knee arthroplasty (TKA) may be considered a viable option for treating the Charcot knee. The use of constrained condylar prostheses can produce satisfactory results. Attention should be given to survival risks, complications, and other potential determining factors associated with TKA when devising a treatment strategy for the Charcot knee.

OBJECTIVE: The purpose of the study was to compare clinical and radiological results between kinematic alignment (KA) and mechanical alignment (MA) with a posterior-stabilized (PS) total knee arthroplasty (TKA) with a post-cam mechanism at a minimum follow-up of 3 years. The authors hypothesized a higher risk of aseptic loosening when performing KA using PS TKA.
METHODS: A retrospective monocentric single surgeon case control study was performed comparing 100 matched patients who had TKA performed using a MA philosophy to 50 patients receiving TKA with a KA technique between January 2016 and October 2017. All patients had the same knee prosthesis (GMK primary posterior-stabilized, Medacta®, Switzerland). Patient specific cutting blocks were used in both groups and a restricted KA (rKA) was aimed in the KA group. A hybrid cementation technique was performed. The new Knee Society Score (KSS) and radiological assessment were collected preoperatively and at the final follow-up. Comparisons between groups were done with the T test or Fisher exact test. Global survival curves were estimated with Kaplan-Meier model. Significance was set at p < 0.05.
RESULTS: Mean follow-up was 42.9 months ± 3.6 (range 37.6-46.7) and 53.3 months ± 4.1 (range 45.5-59.8) for rKA and MA groups. Postoperatively, no significant differences were found for clinical scores between both groups. Radiological assessment found similar postoperative Hip-Knee-Ankle angle for rKA and MA groups (178° versus 179° respectively, NS). At last follow-up, a significant higher survivorship was found for the MA group compared to the rKA group (97 versus 84%; p < 0.001) for aseptic loosening revision as the endpoint.
CONCLUSIONS: An increased risk of tibial implant loosening was found with rKA compared to MA using a posterior-stabilized TKA with a post-cam system at short-term follow-up. Caution should be taken when choosing the TKA design while performing rKA.
METHODS: Retrospective case-control study, Level IV.

Anterior tibiofemoral dislocation after total knee arthroplasty is an extremely rare and serious event. Amongst English-published papers, we found only 15 cases, 3 of which presented vascular complications. This manuscript aims to present a 77-year-old woman with a TC-Plus (Smith & Nephew) cruciate-retaining type in first time of knee prosthesis, who suffered an anterior tibiofemoral dislocation and were admitted to our hospital. The clinical management and outcome were evaluated. Furthermore, a review of literature was performed. We concluded that early detection and surgical intervention of the vascular injury is the key in the survival of the limbs. If there is still knee instability after acute recovery, it seems that revision surgery with constrained total knee arthroplasty can bring about good clinical and functional results.

OBJECTIVE: Very few studies focus on lateral unicompartmental arthroplasty (LUKA) in the setting of post-traumatic osteoarthritis (PTOA). The hypothesis of our study is that LUKA is an effective procedure for isolated lateral PTOA with similar outcomes to non-traumatic LUKA.
METHODS: Between 1990 and 2016, eighteen LUKA performed for isolated lateral tibiofemoral osteoarthritis secondary to tibial plateau fracture were retrospectively reviewed (post-traumatic group) and matched with a control group of thirty-six LUKA performed for non-traumatic OA. Clinical (International Knee Score), radiological outcomes and revision rate were compared between the two groups with a minimum follow-up of three years.
RESULTS: With a mean follow-up of 10.1 years, postoperative IKS scores were similar between the two groups (IKS Knee: 89.1 (control) versus 85 (p = 0.03) and IKS Function: 85.9 (control) versus 77.9 (n.s.). Clinical improvement was greater for the post-traumatic group. No difference was observed with regard to revision rate (3/18 (16.7%) cases in the post-traumatic group and 7/36 (19.4%) in the control group, n.s.) or polyethylene wear per year between the two groups. The revision free-survival rate was 64.8% for the post-traumatic group and 58.8% for the control group at 22-year follow-up (n.s.).
CONCLUSIONS: LUKA is an effective procedure at long-term for patients suffering from isolated lateral PTOA with similar clinical and radiographic results compared to LUKA performed for non-traumatic OA and without increased risk of revision or prosthetic wear.
METHODS: IV.

OBJECTIVE: To investigate the impact of insurance coverage on the adoption of customized individually made (CIM) knee implants and to compare patient outcomes and cost effectiveness of off-the-shelf and CIM implants.
METHODS: A system dynamics simulation model was developed to study adoption dynamics of CIM and meet the research objectives. The model reproduced the historical data on primary and revision knee replacement implants obtained from the literature and the Nationwide Inpatient Sample. Then the dynamics of adoption of CIM implants were simulated from 2018 to 2026. The rate of 90-day readmission, 3-year revision surgery, recovery period, time savings in operating rooms, and the associated cost within 3 years of primary knee replacement implants were used as performance metrics.
RESULTS: The simulation results indicate that by 2026, an adoption rate of 90% for CIM implants can reduce the number of readmissions and revision surgeries by 62% and 39%, respectively, and can save hospitals and surgeons 6% on procedure time and cut down cumulative healthcare costs by approximately $38 billion.
CONCLUSIONS: CIM implants have the potential to deliver high-quality care while decreasing overall healthcare costs, but their adoption requires the expansion of current insurance coverage. This work presents the first systematic study to understand the dynamics of adoption of CIM knee implants and instrumentation. More broadly, the current modeling approach and systems thinking perspective could be used to consider the adoption of any emerging customized therapies for personalized medicine.

The aim of this study was to measure the association between exposure to commonly used oral osteoarthritis (OA) therapies and relevant confounding risk factors on the occurrence of knee replacement (KR), using the Osteoarthritis Initiative (OAI) database.
In this nested case-control design study, participants who had a KR after cohort entry were defined as \"cases\" and were matched with up to four controls for age, gender, income, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain, Kellgren-Lawrence grade, and duration of follow up. Exposure to oral OA therapies (acetaminophen, non-steroidal anti-inflammatory drugs (NSAIDs), cyclooxygenase-2 (COX-2) inhibitors, narcotics, and glucosamine/chondroitin sulfate) was determined within the 3 years prior to the date of the KR. Conditional regression analyses were performed to estimate the association between KR and exposure to oral OA therapies and other potential confounding risk factors.
A total of 218 participants who underwent a KR (cases) were matched to 540 controls. The median time to KR was 4.3 years among cases. The majority in both groups were Caucasian with mean age of 69 years and 61% were female. Numerically, cases were more exposed to acetaminophen, NSAIDs, and COX-2 inhibitors. Exposure to narcotics and glucosamine/chondroitin sulfate was relatively similar between cases and controls. No significant association was found between the occurrence of KR and exposure to any of the oral OA therapies within the 3 years prior to KR. A significantly higher occurrence of KR was found in Caucasian subjects (OR 1.84; 95% CI, 1.13-2.99; p = 0.015) and subjects with body mass index (BMI) ≥ 27 kg/m2 (OR 1.65; 95% CI, 1.06-2.58; p = 0.027).
This study provides evidence that the main risk factors leading to KR are disease severity, symptoms and high BMI. Importantly, exposure to oral OA therapies was not associated with the occurrence of KR.