Bracing improves clinical outcomes but does not affect the medial knee joint space in osteoarthritic patients during gait.

PURPOSE: Osteoarthritis (OA) of the knee is commonly treated through the use of medial compartment unloading braces which have been shown to improve clinical symptoms. The objective of this study was to assess the effects of a medial compartment unloading brace on biomechanical measurements and clinical outcomes. We hypothesized that brace usage would lead to increased medial joint space and improved clinical outcomes. METHODS: Ten patients with medial compartment OA were prescribed a medial compartment unloading brace and underwent dynamic biplane radiograph imaging while walking with and without the brace. The Western Ontario and McMaster University Osteoarthritis (WOMAC) Index was used to assess pain before brace wear and at the time of testing. The 3D position and orientation of the femur and tibia were determined using a model-based tracking technique. RESULTS: Patients saw an average improvement of 33 % in their WOMAC scores (p = 0.01). This study failed to detect any statistically significant changes in the functional joint space, knee kinematics, or contact centre location between the braced and unbraced condition (n.s.). CONCLUSION: The data from this study, using a highly accurate (±0.6 mm and ±0.6°) 3D radiograph analysis of dynamic tibiofemoral motion, suggest that the brace is ineffective at increasing joint space. However, it was shown to be effective in improving clinical outcome and therefore should continue to be prescribed to patients even though the mechanism of its effectiveness remains unknown. LEVEL OF EVIDENCE: IV.

Therapeutic Effects of Gingival Mesenchymal Stem Cells and Their Exosomes in a Chimeric Model of Rheumatoid Arthritis.

Background: Rheumatoid arthritis is a chronic systemic autoimmune disease that involves transformation of the lining of synovial joints into an invasive and destructive tissue. Synovial fibroblasts become transformed, invading and destroying bone and cartilage of the affected joint(s). Due to the significant role these cells play in the progression of the disease process, developing a therapeutic strategy to target and inhibit their invasive destructive nature could help patients who are affiicted with this debilitating disease. Gingival-derived mesenchymal stem cells are known to possess immunomodulatory properties and have been studied extensively as potential cell-based therapeutics for several autoimmune disorders. Methods: A chimeric human/mouse model of synovitis was created by surgically implanting SCID mice with a piece of human articular cartilage surrounded by RASF. Mice were injected once with either GMSC or GMSCExo at 5-7 days post-implantation. Histology and IHC were used to assess RASF invasion of the cartilage. Flow cytometry was used to understand the homing ability of GMSC in vivo and the incidence of apoptosis of RASF in vitro. Results: We demonstrate that both GMSC and GMSCExo are potent inhibitors of the deleterious effects of RASF. Both treatments were effective in inhibiting the invasive destructive properties of RASF as well as the potential of these cells to migrate to secondary locations and attack the cartilage. GMSC home to the site of the implant and induce programmed cell death of the RASF. Conclusions: Our results indicate that both GMSC and GMSCExo can block the pathological effects of RASF in this chimeric model of RA. A single dose of either GMSC or GMSCExo can inhibit the deleterious effects of RASF. These treatments can also block the invasive migration of the RASF, suggesting that they can inhibit the spread of RA to other joints. Because the gingival tissue is harvested with little difficulty, relatively small amounts of tissue are required to expand the cells, the simple in vitro expansion process, and the increasing technological advances in the production of therapeutic exosomes, we believe that GMSCExo are excellent candidates as a potential therapeutic for RA.

The therapeutic effects of gingival mesenchymal stem cells and their exosomes in a chimeric model of rheumatoid arthritis.

BACKGROUND: Rheumatoid arthritis is a chronic systemic autoimmune disease that involves transformation of the lining of synovial joints into an invasive and destructive tissue. Synovial fibroblasts become transformed, invading and destroying the bone and cartilage of the affected joint(s). Due to the significant role these cells play in the progression of the disease process, developing a therapeutic strategy to target and inhibit their invasive destructive nature could help patients who are afflicted with this debilitating disease. Gingival-derived mesenchymal stem cells are known to possess immunomodulatory properties and have been studied extensively as potential cell-based therapeutics for several autoimmune disorders. METHODS: A chimeric human/mouse model of synovitis was created by surgically implanting SCID mice with a piece of human articular cartilage surrounded by RASF. Mice were injected once with either GMSC or GMSCExo at 5-7 days post-implantation. Histology and IHC were used to assess RASF invasion of the cartilage. Flow cytometry was used to understand the homing ability of GMSC in vivo and the incidence of apoptosis of RASF in vitro. RESULTS: We demonstrate that both GMSC and GMSCExo are potent inhibitors of the deleterious effects of RASF. Both treatments were effective in inhibiting the invasive destructive properties of RASF as well as the potential for these cells to migrate to secondary locations and attack the cartilage. GMSC home to the site of the implant and induce programmed cell death of the RASF. CONCLUSIONS: Our results indicate that both GMSC and GMSCExo can block the pathological effects of RASF in this chimeric model of RA. A single dose of either GMSC or GMSCExo can inhibit the deleterious effects of RASF. These treatments can also block the invasive migration of the RASF, suggesting that they can inhibit the spread of RA to other joints. Because the gingival tissue is harvested with little difficulty, relatively small amounts of tissue are required to expand the cells, the simple in vitro expansion process, and the increasing technological advances in the production of therapeutic exosomes, we believe that GMSCExo are excellent candidates as a potential therapeutic for RA.

Females with hip-related pain display altered lower limb mechanics compared to their healthy counterparts in a drop jump task.

BACKGROUND: Hip-related pain describes femoroacetabular impingement syndrome, acetabular dysplasia, and other hip pain conditions without clear morphological features. Movement strategies in this population, notably sex-related patterns, are poorly understood and may provide insights into why females report more pain and worse function. This study examined the sex-related differences during a drop vertical jump task between those with hip-related pain and healthy controls. METHODS: Patients with hip-related pain and healthy controls completed five repetitions of a drop jump while their kinematics and kinetics were recorded using a motion capture system and force plates. Hip, knee, and ankle joint angles and external joint moments during landing were used in general estimating equations for comparison of group by sex by limb interactions. Time series data were further investigated using statistical parametric mapping. FINDINGS: Females with hip-related pain had 9.1° less hip flexion (P = .041) and 9.2° less knee flexion (P = .024) than healthy females, and 8.3° less knee flexion than male counterparts with hip-related pain (P = .039). Males demonstrated 1.4° less hip flexion on the affected side compared to their uninvolved side (P = .004). Statistical parametric mapping results showed significant differences in knee flexion angle for females with hip-related pain compared to healthy females (P = .042). There were no significant differences in hip, knee, or ankle moments. INTERPRETATION: Females with hip-related pain showed kinematic patterns distinct from healthy controls. Sex may be an important variable of interest in characterizing movement impairments in this population and movement impairments may be an appropriate target for intervention for these patients.

Mechanical comparison of meniscal repair devices with mattress suture devices in vitro.

We report the load to failure in tensile testing of the MaxFire™ meniscal repair system (Biomet Inc, Warsaw, IN) and compare it to other current meniscal repair devices and mattress suture techniques. After creating a longitudinal tear in 42 one-year-old bovine menisci, 7 specimen groups defined by the meniscal repair device, suture, and/or mattress technique used for meniscal repair were randomly established: (Group 1: Fiberwire™ vertical mattress (VM), Group 2: Fiberwire™ horizontal mattress (HM), Group 3: FasT-Fix™ VM, Group 4: FasT-Fix™ HM, Group 5: RapidLoc™, Group 6: MaxFire™ VM, Group 7: MaxFire™ HM). After completing the repairs, the meniscal specimens were cyclically pre-loaded before load to failure testing was performed. The mean load to failure for each group was: Fiberwire VM (185 ± 41 N), Fiberwire HM (183 ± 36 N), FasT-Fix VM (125 ± 8 N), FasT-Fix HM (107 ± 29 N), RapidLoc (70 ± 12 N), MaxFire VM (145 ± 44 N), MaxFire HM (139 ± 50 N). An analysis of variance demonstrated a significant difference in the mean load to failure (F = 8.31 P < 0.01). Statistically significant differences were seen between both Fiberwire groups verses FasT-Fix HM and Rapid-Loc (P < 0.05). Three modes of failure were observed: suture breakage (17/42, 40.5%), tissue failure (18/42, 42.9%), and knot failure (7/42, 16.7%). 2-0 Fiberwire™ VM and HM repairs had the highest load to failure of all groups tested. The load to failure for the MaxFire™ meniscal repair system is comparable to other available all-inside meniscal repair systems.

Independent risk factors for recurrent or multiple new injuries in CrossFit athletes.

BACKGROUND: CrossFit is a relatively new sport with rapidly growing participation rates in the United States and around the world. We sought to determine risk factors for sustaining multiple CrossFit-related injuries requiring medical evaluation. METHODS: CrossFit-related musculoskeletal injuries evaluated at a single hospital system (N.=837) were identified. For musculoskeletal injuries, use of physical therapy, injection, advanced diagnostic imaging including CT or MRI, and surgery were documented. Independent risk factors for sustaining multiple injuries requiring medical evaluation were assessed by multivariate logistic regression analysis. RESULTS: A total of 94/837 (11.2%) underwent evaluation for 2 or more CrossFit-Related injuries (74% new injury to different body part; 26% subsequent injury, same body part). Independent risk factors for repeat injury (recurrent injury or second new injury) included increased length of follow-up (per year: OR 1.50 CI: 1.29, 1.75; P<0.001), initial injury during spring season (OR 2.03 CI: 1.27, 3.26; P=0.004), advanced imaging not obtained for evaluation of initial injury (OR 2.62 CI: 1.37, 5.02; P=0.002), course of physiotherapy completed for initial injury (2.00 CI: 1.17, 3.41; P=0.008), corticosteroid injection administered for initial injury (OR 2.43 CI: 1.21, 4.88; P=0.01), and increased age (per 5 year increase: OR 1.12 CI: 1.01, 1.24; P=0.03). These risk factors in combination had moderate discriminatory ability for identifying athletes at risk for multiple injuries. CONCLUSIONS: There are multiple risk factors for sustaining a recurrent or second new CrossFit-related injury requiring medical evaluation including older age, length of participation, and spring season participation. Risk factors for repeat injury related to initial evaluation and treatment include not receiving advanced imaging, receiving a corticosteroid injection, or undergoing physical therapy. The anatomic site of initial injury was not related to risk of subsequent injury in this population.

Factors Associated with Initial Interest and Treatment Selection in Patients with Femoroacetabular Impingement Syndrome.

BACKGROUND: Outcomes for operative and nonoperative management of femoroacetabular impingement syndrome (FAIS) are variable. Understanding factors that inform patients' treatment decisions may optimize their outcomes. OBJECTIVE: To identify factors that predict which patients with FAIS proceed to surgery within 90 days of their initial evaluation by an orthopedic surgeon. The study explored potential predictors of surgical intervention, including demographic factors, activity level, symptom duration, previous treatment, hip function, pain, presence of labral tear, and patient interest in surgical and physical therapy (PT) treatment. DESIGN: Prospective cohort. SETTING: Single-site academic medical center. PATIENTS: Seventy-seven individuals with FAIS. INTERVENTION: After evaluation in a hip preservation clinic, participants reported activity level, symptom duration, treatment history, hip function [Hip Outcome Score Activities of Daily Living(HOS-ADL)], pain severity and location, and treatment interests. These variables were evaluated based on univariate analysis for entry into a multiple binomial logistic regression to identify predictors of surgery within 90 days. Adjusted marginal prevalence ratios and 95% confidence interval estimates (PR [95% CI]) were reported (P ≤ .05). MAIN OUTCOME MEASURE(S): Ninety-day treatment (surgery or not). RESULTS: Participants indicated initial interest in surgery (n = 27), PT (n = 22), both (n = 18), or neither (n = 10). Those only interested in PT had lower prevalence of diagnosed labral tear (P < .001) and previous PT for the hip (P < .001). Prevalence of previous injection was higher for those only interested in surgery than for those with any interest in PT (P < .001). Thirty-six of 77 participants (46%) underwent surgery within 90 days. Surgical interest (3.56 [1.57, 5.46]), previous hip injection (3.06 [1.73, 3.89]), younger age (0.95 [0.92, 0.98]), and worse hip function (0.97 [0.95, 0.99]) were significant (P ≤ .02) predictors of surgery. CONCLUSIONS: Treatment interest and history, patient function, and age were significantly related to participants' decision to pursue surgical intervention within 90 days. Patient engagement in the decision-making process should include considerations of patient knowledge of, and experience with, the various treatment options.

Management of Labral and Chondral Disease in Hip Preservation Surgery.

The techniques utilized for the management of articular cartilage and labrum injuries during hip preservation surgery have changed dramatically recently. Conservative treatment may involve image-guided injection of cortisone or viscosupplementation in conjunction with oral NSAIDs and physical therapy. Damage to the labrum runs a broad spectrum, and the treatments are individualized, but span from debridement to repair and reconstruction. The overarching goal of labral treatment is to restore the native functions of the labrum to allow for more normal biomechanical function. Similarly, cartilage injuries can be managed a number of different ways, including with debridement, microfracture or drilling, cartilage transplants, and higher level restorative techniques. These cartilage restoration techniques have evolved rapidly as well, and may include the use of scaffolds, allograft cartilage cells, and other stem-cell-related procedures.