Knee dislocations and associated fractures: risk factors for surgical reduction.

INTRODUCTION: Dissociation of the knee joint, or knee dislocations (KD), can lead to severe complications, often resulting in multiligament injuries. A subset of these injuries are irreducible by closed reduction and require open reduction. Identifying KDs that necessitate surgical intervention is crucial for optimal outcomes. While previous studies have explored various risk factors, the influence of associated fractures is less understood. MATERIALS AND METHODS: We queried the Trauma Quality Improvement Program (TQIP) database from 2017 to 2021, for non-congenital closed knee dislocations requiring surgery. Demographic variables were collected, and ICD-10 codes were used to identify associated tibia, femur, acetabular, and fibula fractures. ICD-10 codes were also used to identify nerve injuries and vascular injuries. Multivariate logistic regression was used to assess factors influencing the need for surgical reduction (SR). RESULTS: A total of 1,467 patients with KDs were included in the study, of which 411 (28.0%) underwent open surgical reduction (SR) while 1,056 (72.0%) were treated with nonsurgical closed reduction (nSR). Factors associated with SR included concomitant tibia fracture (OR = 1.683, C.I: 1.255-2.256, p < 0.001) and fibula fracture (OR = 1.457, C.I: 1.056-2.011, p = 0.022). Vascular injury had lower odds of SR (OR = 0.455, C.I: 0.292-0.708, p < 0.001). CONCLUSION: Our study demonstrated that KDs presenting with concomitant tibia and/or fibula fractures are more likely to require SR. The difficulty posed to closed reduction may be due to the influence of these fracture patterns on surrounding soft tissue as well as the lack of a stable bone structure necessary for achieving proper reduction. Physicians should be aware of the potential risk of this fracture pattern when caring for patients with KDs.

A novel large animal model of posttraumatic osteoarthritis induced by inflammation with mechanical stability.

OBJECTIVES: Animal models are needed to reliably separate the effects of mechanical joint instability and inflammation on posttraumatic osteoarthritis (PTOA) pathogenesis. We hypothesized that our modified intra-articular drilling (mIAD) procedure induces cartilage damage and synovial changes through increased inflammation without causing changes in gait. METHODS: Twenty-four Yucatan minipigs were randomized into the mIAD (n=12) or sham control group (n=12). mIAD animals had two osseous tunnels drilled into each of the tibia and femur adjacent to the anterior cruciate ligament (ACL) attachment sites on the left hind knee. Surgical and contralateral limbs were harvested 15 weeks post-surgery. Cartilage degeneration was evaluated macroscopically and histologically. Synovial changes were evaluated histologically. Interleukin-1 beta (IL-1ß), nuclear factor kappa B (NF-κB), and tumor necrosis factor alpha (TNF-α) mRNA expression levels in the synovial membrane were measured using quantitative real-time polymerase chain reaction. IL-1ß and NF-κB levels in chondrocytes were assessed using immunohistochemistry. Load asymmetry during gait was recorded by a pressure-sensing walkway system before and after surgery. RESULTS: The mIAD surgical knees demonstrated greater gross and histological cartilage damage than contralateral (P<.01) and sham knees (P<.05). Synovitis was present only in the mIAD surgical knee. Synovial inflammatory marker (IL-1ß, NF-κB, and TNF-α) expression was three times higher in the mIAD surgical knee than the contralateral (P<.05). Chondrocyte IL-1ß and NF-κB levels were highest in the mIAD surgical knee. In general, there were no significant changes in gait. CONCLUSIONS: The mIAD model induced PTOA through inflammation without affecting gait mechanics. This large animal model has significant applications for evaluating the role of inflammation in PTOA and for developing therapies aimed at reducing inflammation following joint injury.

Risk Factors and Outcomes for Preoperative Stiffness Requiring Intervention Before Anterior Cruciate Ligament Reconstruction.

Background: To date, there is a scarcity of literature related to the incidence of prolonged stiffness after an anterior cruciate ligament (ACL) tear that requires manipulation under anesthesia/lysis of adhesions (MUA/LOA) in the preoperative period before ACL reconstruction (ACLR) and how preoperative stiffness influences outcomes after ACLR. Hypothesis: Preoperative stiffness requiring MUA/LOA would increase the risk for postoperative stiffness, postoperative complications, and the need for subsequent procedures after ACLR. Study Design: Cohort study; Level of evidence, 3. Methods: The PearlDiver Research Program was used to identify patients who sustained an ACL tear and underwent ACLR using their respective International Classification of Diseases, 9th or 10th Revision, and Current Procedure Terminology (CPT) codes. Within this group, patients with preoperative stiffness were identified using the CPT codes for MUA or LOA. Significant risk factors for preoperative stiffness were identified through univariate and multivariate logistic regression analyses. Outcomes after ACLR were analyzed between patients with and without preoperative stiffness using multivariate logistic regression, controlling for age, sex, and Elixhauser Comorbidity Index. Results: Between 2008 and 2018, 187,071 patients who underwent ACLR were identified. Of these patients, 241 (0.13%) underwent MUA/LOA before ACLR. Patients with preoperative stiffness began preoperative physical therapy significantly later than patients without stiffness (P = .0478) and had a delay in time to ACLR (P = .0003). Univariate logistic regression demonstrated that female sex, older age, anxiety/depression, obesity, and anticoagulation use were significant risk factors for preoperative stiffness (P < .05 for all). After multivariate regression, anticoagulation use was the only independent risk factor deemed significant (odds ratio, 6.69 [95% CI, 4.01-10.51]; P < .001). Patients with preoperative stiffness were at an increased risk of experiencing postoperative stiffness, deep vein thrombosis, pulmonary embolism, surgical-site infection, and septic knee arthritis after ACLR (P < .05 for all). Conclusion: Although the risk of preoperative stiffness requiring an MUA/LOA before ACLR is low, the study findings indicated that patients with preoperative stiffness were at increased risk for postoperative complications compared with patients with no stiffness before ACLR.

Localized Pigmented Villonodular Synovitis Originating from the Lateral Meniscus in a 17-year-old: Case Report and Literature Review of Meniscal-Associated Localized PVNS.

Tenosynovial giant cell tumors (TSGCT) are benign tumors originating from the synovial joint, bursa, or tendon sheath. Localized pigmented villonodular synovitis (PVNS), a subtype of TSGCT, commonly affects the hands and feet and has also been reported in the literature in the knee joint. There is sparse literature on localized PVNS arising specifically from meniscal tissue. We present a case report of a 17-year- old male with symptoms and MRI findings consistent with a lateral meniscus tear. Intraoperatively, the patient was found to have a mass originating from the torn meniscal tissue, which was confirmed by pathology to be a TSGCT. We performed a literature review of intra-articular localized PVNS within the knee presenting as a meniscal tear.

A Review of Abductor Tendon Tears: The Hidden Lesion of the Hip.

¼: Greater trochanteric pain syndrome consists of a group of associated conditions involving the lateral hip that can be debilitating to patients, mostly women between ages 40 and 60 years. ¼: Abductor tendon tears are becoming a more recognized cause of lateral hip pain in patients without hip osteoarthritis. ¼: Diagnosis of this condition is critical to patient care because misdiagnosis often leads to unnecessary prolonged pain and even unnecessary procedures that address different pathologies. ¼: Treatment strategies consists of nonoperative modalities such as nonsteroidal anti-inflammatory medications, corticosteroid injections, and physical therapy, but for refractory cases, surgical techniques including repair, augmentation, and reconstruction have been well-described in the literature providing patients with acceptable outcomes.

Electromyography as a surrogate for estimating metabolic energy expenditure during locomotion.

Minimizing metabolic energy expenditure (MEE) plays an important role in increasing mobility in people with locomotor disabilities, as movements that require high energy lead to less activity. Rehabilitation programs and devices use MEE to determine how effective they are, but using indirect calorimetry is limiting due to time delays and non-real-world conditions. Electromyography (EMG) offers insight into how muscles activate; thus, the purpose of this study was to develop a real-time MEE feedback system through the utilization of EMG signals. Participants completed five walking conditions at different stride frequencies (preferred, +/- 15%, +/- 30%), while breath-by-breath gas exchange, ground reaction forces and EMG signals were collected. The live EMG signal was numerically integrated and separated into strides, then scaled by a cost of force (COF) coefficient. MEE had the expected quadratic relationship seen in previous literature (R2 = 0.967), along with COF data (R2 = 0.701). The EMG method stabilized between 75.1% - 133.1%, which is not within a close range (90% - 110%) of MEE; thus, future studies must investigate other mathematical methods. Our results indicate a qualitative association between MEE and EMG activity, which could be used to increase mobility and quality of life for populations with disability.

The Physiological Effects, Including Risks and Potential Benefits, of Cannabis for Patients Undergoing Elective Orthopedic Procedures.

Given the evolving regulations regarding and availability of cannabis in the United States, physicians should understand the risks and benefits associated with its use. Patients are interested in learning about the use of cannabis for the management of orthopedic pain and any potential risks associated with it when undergoing elective surgery. Edible and topical cannabis products appear to have fewer side effects than inhaled cannabis products. A review of the literature was performed regarding different modes of administration and their related risks and potential benefits specifically regarding perioperative concerns for elective orthopedic procedures. Larger studies are necessary to further determine the efficacy, safety, and side effect profile of cannabis. [Orthopedics. 2021;44(3):e314-e319.].

Early success of the arthroscopic-assisted locked loop suprapectoral biceps tenodesis.

Background: There is wide variability in surgical technique for biceps tenodesis. Prior biomechanical studies have demonstrated superior ultimate and fatigue strength with a Krakow-type locked loop when compared with simple suture and lasso-loop configurations; however, this had not yet been clinically studied. The purpose of this study was to assess the short-term results an arthroscopic-assisted locked loop (ALL) suprapectoral biceps tenodesis technique. Methods: All patients who underwent an ALL suprapectoral biceps tenodesis by a single surgeon from 2012 and 2019 with a minimum of 12-month follow-up were analyzed. Data collected included demographics, surgical indications, concomitant operative procedures, and postoperative complications of anterior shoulder "groove" pain, "Popeye deformity," biceps muscle cramping pain, and need for revision surgery. Results: Forty patients who underwent an ALL suprapectoral biceps tenodesis met inclusion criteria. Patients were 55.6 ± 8.6 years of age, consisting of 28 men (57%) and 21 women (43%). The median follow-up was 19.3 months. At the latest follow-up, 1 (2%) patient had anterior shoulder "groove" pain, and no patients had a Popeye deformity or biceps muscle cramping. There were no revision biceps tenodesis procedures. Conclusion: The ALL suprapectoral biceps tenodesis technique results in a low incidence of postoperative complications. At a short-term follow-up of 1 year, no patients had reoperations or revisions for failed biceps tenodesis. Groove pain was nearly absent in this series of patients.

Distal Radius Fractures in Patients Aged 50 Years or Older: Obstacles to Bone Health Analysis and Follow-Up in a Community Setting.

Purpose: To determine barriers to implementing an osteoporosis protocol in a community institution following distal radius (DR) fragility fracture to help prevent subsequent fragility fractures. Methods: This cross-sectional study included elderly patients with DR fractures that occurred between 2016 and 2018. Exclusion criteria were age under 50 years, high-energy mechanism, and inability to follow-up locally. Patients were directed to follow-up with the hospital's osteoporosis center (OC) or an endocrinologist. Patients were contacted to identify if care was established with the OC and screened for potential barriers in evaluation for bone health. Primary outcomes included the completion of a follow-up visit with an osteoporosis care provider and identification of barriers for patients who did not complete this visit. Secondary outcomes included whether or not patients obtained bone health labs, dual-energy x-ray absorptiometry (DEXA) scans, and/or underwent medical treatment for osteoporosis. Results: One hundred seventy-five patients met final inclusion criteria and were contacted after discharge. Fifty patients agreed to follow-up with the OC, voicemails were left for 66 patients, only 70 (60.3%) patients actually followed up for bone health analysis. Patients were lost to follow-up due to lack of accessibility (32 patients; death, incorrect phone number, no voicemail, or impaired cognition), and lack of interest (27 patients). Ninety-six (54.9%) patients received appropriate treatment based on bone health labs and/or DEXA scan. Ninety (51.4%) patients had chemical treatment for osteoporosis. Fifty-five patients underwent DEXA scans with equal distribution of patients with normal, osteopenic, and osteoporotic bone. Forty-three (78%) patients who had DEXA scans underwent treatment. Conclusions: Establishing a protocol for follow-up for bone health assessment following a DR fracture is challenging. Only half of the patients underwent evaluation and management of their bone health. It is imperative to understand the barriers for at-risk patients to provide them with care that will improve their quality of life. Type of study/level of evidence: Diagnostic III.

Live imaging analysis of human gastric epithelial spheroids reveals spontaneous rupture, rotation and fusion events.

Three-dimensional cultures of primary epithelial cells including organoids, enteroids and epithelial spheroids have become increasingly popular for studies of gastrointestinal development, mucosal immunology and epithelial infection. However, little is known about the behavior of these complex cultures in their three-dimensional culture matrix. Therefore, we performed extended time-lapse imaging analysis (up to 4 days) of human gastric epithelial spheroids generated from adult tissue samples in order to visualize the dynamics of the spheroids in detail. Human gastric epithelial spheroids cultured in our laboratory grew to an average diameter of 443.9 ± 34.6 µm after 12 days, with the largest spheroids reaching diameters of >1000 µm. Live imaging analysis revealed that spheroid growth was associated with cyclic rupture of the epithelial shell at a frequency of 0.32 ± 0.1/day, which led to the release of luminal contents. Spheroid rupture usually resulted in an initial collapse, followed by spontaneous re-formation of the spheres. Moreover, spheroids frequently rotated around their axes within the Matrigel matrix, possibly propelled by basolateral pseudopodia-like formations of the epithelial cells. Interestingly, adjacent spheroids occasionally underwent luminal fusion, as visualized by injection of individual spheroids with FITC-Dextran (4 kDa). In summary, our analysis revealed unexpected dynamics in human gastric spheroids that challenge our current view of cultured epithelia as static entities and that may need to be considered when performing spheroid infection experiments.