Journal of Musculoskeletal Research

Background: Osteoarthritis (OA) is a leading cause of morbidity affecting 54 million Americans per year at an annual cost of 304 billion dollars to the US healthcare system. OA is characterized as a disease of joint wear and tear, but mounting evidence suggests a role for aberrant activation of immunity to contribute to disease progression. Methods: We hypothesized that OA patients have differential profiles of immunity between peripheral and synovial compartments as an indication that in situ immunity is affected by OA or vice versa. We used FACS analysis to phenotype T cell and myeloid populations between peripheral and synovial compartments from 16 patients undergoing total joint replacement due to advanced OA. Results: Our finding that Foxp3$+$ T regulatory (Tregs) increasingly comprise SF immunity of OA patients is novel ($p=0.034$). Though the periphery harbored greater numbers of lymphocyte and myeloid cells compared to synovial fluid ($p=0.068$), the synovial fluid revealed elevated percentages of myeloid (Cd11b$+$) cells that comprised the CD45$+$ population ($p=0.021$). Further, characterization elucidated that CD45/CD11b/CD14$+$/CD15- cells upregulated HLADR in the affected synovial fluid ($p=0.039$) and that these cells increase expression of CD68 ($p=0.062$). Conclusions: Our data indicate that the affected joint space in OA patients harbors phenotypically distinct T-cell and myeloid populations compared to autologous-matched peripheral immunity. The contribution of aberrant immune populations to development and progression of OA is of interest for novel immunotherapies.

Peri-implant debris certainly lead to osteolysis, necrosis, pseudotumor formation, tissue granulation, fibrous capsule contractions, and even implant failure. For the three-dimensional (3D) printed cage, impaction during cage insertion is one of the most potential sources of fracture debris. A finite-element study was carried out to reduce the impact-induced debris of the 3D-printed cage. This study focused on the design strategy of solid and cellular structures along the load-transferring path. Using the finite-element method, the cellular structure of the transforaminal lumbar interbody fusion (TLIF) cage was systematically modified in the following four variations: a noncellular cage (NC), a fully cellular (FC) cage, a solid cage with a cellular structure in the middle concave (MC) zone, and a strengthened cage (SC) in the MC zone. Three comparison indices were considered: the stresses at the cage-instrument interfaces, in the MC zone, and along the specific load-transferring path. The NC and FC were the least and most highly stressed variations at the cage-instrument interfaces and in the MC zone, respectively. Along the entirely load-transferring path, the FC was still the most highly stressed variation. It showed a higher risk of stress fracture for the FC cage. For the MC and SC, the MC zone was consistently more stressed than the directly impacted zone. The further strengthened design of the SC had a lower peak stress (approximately 29.2%) in the MC zone compared with the MC. Prior to 3D printing, the load-transferring path from the cage-instrument interfaces to the cage-tissue interfaces should be determined. The cage-instrument interfaces should be printed as a solid structure to avoid impact-induced fracture. The other stress-concentrated zones should be cautiously designed to optimize the coexistence strategy of the solid and cellular structures.

Objective: Patient-specific positioning guides have been designed to improve precision in total knee arthroplasty. The aim of this study is to evaluate the medium-term clinical and radiological outcomes with magnetic resonance imaging-based patient-specific positioning guides. Material and methods: We retrospectively reviewed patients from two centers treated with total knee arthroplasty performed with patient-specific positioning guides. We enrolled patients operated on between January 2011 and December 2013, with a minimum follow-up of 5 years. Preoperative and postoperative hip knee angle (HKA) and position of each component in the coronal plane were assessed. Overall malalignment was defined as an outlier of more than $3^{\circ }$ from the neutral mechanical axis and specific malalignment as when any component showed more than $2^{\circ }$ of deviation. Clinical outcomes were evaluated using the Hospital for Special Surgery (HSS) knee Score. Results: This study included 68 patients with a mean age of 72 years. The mean postoperative alignment (HKA) was $181.5^{\circ }$ and 26.5% of patients showed coronal malalignment $>3^{\circ }$. Regarding femoral components, 19.1% showed specific malalignment $(>\pm 2^{\circ })$, while 11.7% of tibial components were classified as outliers. The mean HSS Knee Score at final follow up was 89.2. Patients whose implants were mechanically aligned did not obtain better functional outcomes ($p=0.3$). Conclusion: In our series, the use of patient-specific positioning guides resulted in a range of mechanical malalignment, similar to conventional instrumentation results reported in the literature.

Multiple sclerosis (MS) is a type of degenerative syndrome that causes impaired physical function, decreased walking, imbalance, spasticity, sensory impairment, muscle weakness, fatigue, and demyelination of the central nervous system. The purpose of this review was to critically examine available studies on the efficacy of whole-body vibration (WBV) in patients with MS during rehabilitation training to increase strength, balance, and functional mobility. An organized literature search was performed on databases from various sources, including PubMed, MEDLINE, CINAHL, and EMBASE, to identify relevant randomized clinical trials (RCTs). Eight studies were finally selected based on exclusion and inclusion criteria. Attempts were made to identify factors affecting the improvement in muscle strength, balance, and functional mobility in MS patients as a result of WBV. A meta-analysis was performed if two or more studies measured the same outcome of interest. The meta-analysis found that the WBV intervention showed significant improvement over control groups in Body Balance Score (BBS) (MD = $-$2.86, 95%CI = $-$5.29 $-$ 0.43; $Z=2.31$, $p=0.02$, heterogeneity ($I^2=91$%). In addition, walking endurance (6MWT) favored control groups over WBV intervention (MD $=59.86$, 95%CI $=20.3$$-$ 99.41; $Z$ = 2.97, $p=0.003$). Timed-Up-and-Go Test (TUG) and Expanded Disability Status Scale (EDSS) ($p>0.05$) had no significant effect on WBV. Restoration of balance and functional mobility appeared to respond better to WBV with additional exercise protocols compared to WBV alone. Although there is evidence of an overall effect of WBV on strength and some measures of balance and mobility, its impact remains inconclusive. Therefore, more robust RCTs examining exposure to WBV on balance and functional mobility in patients with MS are warranted.

Purpose: To assess the preoperative body mass indices of various orthopaedic conditions, there are a few previous nutritional studies in surgical patients, and none did solely the BMI study in general population in Korea. The current authors planned indirectly to evaluate the Koreans’ obesity. Methods: BMI was used to assess the obesity status of the 2063 orthopaedic patients who were subjected to surgeries; 1272 fractures, 490 various elective surgeries, 232 arthroplasties, 59 musculoskeletal infections, and 10 uninfected diabetics, in Jeju island. Results: Among total 2063 patients, 101 patients (4.8%) had underweight, normal weight in 1220 patients (59.1%), overweight in 630 (30.5%), and the so-called “obese” in 124 cases (6.0%). The obesity in detail of each group is listed in Table 2–6.

Among 1272 fracture cases, underweight in 79 (6.2%), normal weight in 752 (61.5%), overweight in 345 (27.1%), and overall class I–III obese in 66 (5.1%). 490 elective surgery patients had overweight in 34.5% and obese in 7.1%. The incidences of obesity in each condition are nearly similar, ranging from 5.2% to 7.3% except for the diabetic one. Conclusions: This study on BMI of the orthopaedic patients disclosed that the incidence of obesity is not high yet in Jeju islanders, in spite of the highly improved living standard.

Background: Chronic nonspecific low back pain (CNSLBP) is the leading cause of long-term pain and disability. There is evidence suggesting a relationship between CNSLBP in adult women and altered hip kinematics and gluteus medius (GM) muscle function. However, this association has been less studied in young women. Objective: To assess the association between lower limb and pelvis kinematics in the frontal plane, and GM strength and electromyographic activity in young women with CNSLBP compared with an age-matched control group of asymptomatic women. Methods: In this cross-sectional study, 32 young women with CNSLBP ($>6$ months of pain; Oswestry index range: 21–40%) and 20 healthy age-matched women were included. The frontal plane projection angle (FPPA) and contralateral pelvis drop (CPD) at the endpoint of the single-leg squat (SLS) test were measured through photogrammetry. Mean GM muscle activity during the SLS and peak isometric GM strength was measured using surface electromyography (sEMG) and hand-held dynamometry, respectively. Results: The Hotelling’s trace showed no significant differences between groups when the variables were considered as a composite ($F=0.69$; $p=0.76$). Also, the univariate results showed no individual differences between groups considering each variable separately. Conclusions: The results showed no association between CNSLBP, hip and pelvis kinematics, and GM strength and activity in young women.

Background: A comparative analysis of the role of various proximal femoral nail antirotation (PFNA) lengths in the union of trochanteric fracture in elderly patients treated with long and short PFNA. Objective: To investigate the significance of PFNA length in trochanteric fracture union in elderly patient. Materials and methods: A retrospective review study was conducted in elderly patients with trochanteric fractures treated between March 2010 and December 2017 in a tertiary care hospital. Hospital records of 517 patients who were treated for trochanteric fracture with various sizes of PFNA, were analyzed as per inclusion criteria and finally 503 patients records were included in the study, of which 261 were treated with short PFNA and 242 with long PFNA. The patients were allocated to two groups: those treated with long nail ($n=242$) and short nail ($n=261$). Demographic data were comparatively analyzed regarding the time of fracture union and complications. Results: In this study, no remarkable differences were noted between two groups with regards to types of fracture, time from injury to surgery and duration of hospital stay. The duration of surgery in a short PFNA was significantly less (60.5min) compared to that of a long PFNA (82.2min). However, the time taken for fracture to unite was not statistically significant. Conclusions: The variation in the length of the nail whether short or long does not affect union in trochanteric fracture in the elderly however surgical duration for short nail was much less than the long nail.