Differences in Achilles tendon mechanical properties between professional ballet dancers and collegiate athletes utilizing shear wave elastography.

PURPOSE: To report normative stiffness parameters obtained using shear wave elastography in dorsiflexion from the Achilles tendons in asymptomatic professional ballet dancers and compare them with college-level athletes. METHODS: An Institutional Review Board (IRB)-approved study consists of 28 professional ballet dancers and 64 asymptomatic collegiate athletes. The athletes were further subdivided into runner and non-runner disciplines. Shear wave elastography (SWE) measurements were made in maximum ankle dorsiflexion position. RESULTS AND DISCUSSION: Forty-eight (52%) males and 44 (48%) females were examined with an overall mean age of 22.2 (± 3.8 years). There were no significant SWE differences between dominant and non-dominant legs in both groups and comparing spin vs. non-spin leg of ballet dancers (p > 0.05). Ballet dancers had significantly higher short-axis velocity values than runners and non-runners (2.34 m/s increase and 2.79 m/s increase, respectively, p < 0.001). Long-axis velocity was significantly higher in ballet dancers compared to non-runners (by 0.80 m/s, p < 0.001), but was not different between ballet dancers and runners (p > 0.05). Short-axis modulus was significantly higher in dancers compared to runners and non-runners (by 135.2 kPa and 159.2 kPa, respectively, p < 0.001). Long-axis modulus (LAM) was not significantly different in ballet dancers when compared to runners. CONCLUSION: Asymptomatic professional ballet dancers exhibit greater short-axis tendon stiffness compared to athletes and greater long-axis tendon stiffness compared to non-runners but similar to runners. The functional benefit from elevated short-axis stiffness in dancers is not clear but may be related to greater axial loading and adaptations of the tendon matrix.

Feasibility of Multiparametric Perfusion Assessment in Diabetic Foot Ulcer Using Intravoxel Incoherent Motion and Blood Oxygenation-Level Dependent MRI.

BACKGROUND: Patients with type-2 diabetes (T2DM) are at increased risk of developing diabetic foot ulcers (DFU) and experiencing impaired wound healing related to underlying microvascular disease. PURPOSE: To evaluate the sensitivity of intra-voxel incoherent motion (IVIM) and blood oxygen level dependent (BOLD) MRI to microvascular changes in patients with DFUs. STUDY TYPE: Case-control. POPULATION: 20 volunteers who were age and body mass index matched, including T2DM patients with DFUs (N = 10, mean age = 57.5 years), T2DM patients with controlled glycemia and without DFUs (DC, N = 5, mean age = 57.4 years) and healthy controls (HC, N = 5, mean age = 52.8 years). FIELD STRENGTH/SEQUENCE: 3T/multi-b-value IVIM and dynamic BOLD. ASSESSMENT: Resting IVIM parameters were obtained using a multi-b-value diffusion-weighted imaging sequence and two IVIM models were fit to obtain diffusion coefficient (D), pseudo-diffusion coefficient (D*), perfusion fraction (f) and microvascular volume fraction (MVF) parameters. Microvascular reactivity was evaluated by inducing an ischemic state in the foot with a blood pressure cuff during dynamic BOLD imaging. Perfusion indices were assessed in two regions of the foot: the medial plantar (MP) and lateral plantar (LP) regions. STATISTICAL TESTS: Effect sizes of group mean differences were assessed using Hedge's g adjusted for small sample sizes. RESULTS: DFU participants exhibited elevated D*, f, and MVF values in both regions (g ≥ 1.10) and increased D (g = 1.07) in the MP region compared to DC participants. DC participants showed reduced f and MVF compared to HC participants in the MP region (g ≥ 1.06). Finally, the DFU group showed reduced tolerance for ischemia in the LP region (g = -1.51) and blunted reperfusion response in both regions (g < -2.32) compared to the DC group during the cuff-occlusion challenge. DATA CONCLUSION: The combined use of IVIM and BOLD MRI shows promise in differentiating perfusion abnormalities in the feet of diabetic patients and suggests hyperperfusion in DFU patients. LEVEL OF EVIDENCE: 1 TECHNICAL EFFICACY: Stage 1.

Differences in peripheral microcirculatory blood flow regulation in chronic kidney disease based on wavelet analysis of resting near-infrared spectroscopy.

Vascular impairment is closely related to increased mortality in chronic kidney disease (CKD). The objective of this study was to assess impairments in the regulation of peripheral microvascular perfusion in patients with CKD based on time-frequency spectral analysis of resting near-infrared spectroscopy (NIRS) signals. Total hemoglobin (tHb) concentration and tissue saturation index (TSI) signals were collected using NIRS for a continuous 5 mins at 10 Hz from the forearm of 55 participants (34 CKD including 5 with end-stage renal disease, and 21 age-matched control). Continuous wavelet transform-based spectral analysis was used to quantify the spectral amplitude within five pre-defined frequency intervals (I, 0.0095-0.021 Hz; II, 0.021-0.052 Hz; III, 0.052-0.145 Hz; IV, 0.145-0.6 Hz and V, 0.6-2.0 Hz), representing endothelial, neurogenic, myogenic, respiratory and heartbeat activity, respectively. CKD patients showed lower tHb average spectral amplitude within the neurogenic frequency interval compared with controls (p = 0.014), consistent with an increased sympathetic outflow observed in CKD. CKD patients also showed lower TSI average spectral amplitude within the endothelial frequency interval compared with controls (p = 0.046), consistent with a reduced endothelial function in CKD. These findings demonstrate the potential of wavelet analysis of NIRS to provide complementary information on peripheral microvascular regulation in CKD.

Age-related changes in human skeletal muscle microstructure and architecture assessed by diffusion-tensor magnetic resonance imaging and their association with muscle strength.

Diffusion-tensor magnetic resonance imaging (DT-MRI) offers objective measures of muscle characteristics, providing insights into age-related changes. We used DT-MRI to probe skeletal muscle microstructure and architecture in a large healthy-aging cohort, with the aim of characterizing age-related differences and comparing these to muscle strength. We recruited 94 participants (43 female; median age = 56, range = 22-89 years) and measured microstructure parameters-fractional anisotropy (FA) and mean diffusivity (MD)-in 12 thigh muscles, and architecture parameters-pennation angle, fascicle length, fiber curvature, and physiological cross-sectional area (PCSA)-in the rectus femoris (RF) and biceps femoris longus (BFL). Knee extension and flexion torques were also measured for comparison to architecture measures. FA and MD were associated with age (ß = 0.33, p = 0.001, R2 = 0.10; and ß = -0.36, p < 0.001, R2 = 0.12), and FA was negatively associated with Type I fiber proportions from the literature (ß = -0.70, p = 0.024, and R2 = 0.43). Pennation angle, fiber curvature, fascicle length, and PCSA were associated with age in the RF (ß = -0.22, 0.26, -0.23, and -0.31, respectively; p < 0.05), while in the BFL only curvature and fascicle length were associated with age (ß = 0.36, and -0.40, respectively; p < 0.001). In the RF, pennation angle and PCSA were associated with strength (ß = 0.29, and 0.46, respectively; p < 0.01); in the BFL, only PCSA was associated with strength (ß = 0.43; p < 0.001). Our results show skeletal muscle architectural changes with aging and intermuscular differences in the microstructure. DT-MRI may prove useful for elucidating muscle changes in the early stages of sarcopenia and monitoring interventions aimed at preventing age-associated microstructural changes in muscle that lead to functional impairment.

Multi-frame biomechanical and relaxometry analysis during in vivo loading of the human knee by spiral dualMRI and compressed sensing.

PURPOSE: Knee cartilage experiences repetitive loading during physical activities, which is altered during the pathogenesis of diseases like osteoarthritis. Analyzing the biomechanics during motion provides a clear understanding of the dynamics of cartilage deformation and may establish essential imaging biomarkers of early-stage disease. However, in vivo biomechanical analysis of cartilage during rapid motion is not well established. METHODS: We used spiral displacement encoding with stimulated echoes (DENSE) MRI on in vivo human tibiofemoral cartilage during cyclic varus loading (0.5 Hz) and used compressed sensing on the k-space data. The applied compressive load was set for each participant at 0.5 times body weight on the medial condyle. Relaxometry methods were measured on the cartilage before (T1ρ , T2 ) and after (T1ρ ) varus load. RESULTS: Displacement and strain maps showed a gradual shift of displacement and strain in time. Compressive strain was observed in the medial condyle cartilage and shear strain was roughly half of the compressive strain. Male participants had more displacement in the loading direction compared to females, and T1ρ values did not change after cyclic varus load. Compressed sensing reduced the scanning time up to 25% to 40% when comparing the displacement maps and substantially lowered the noise levels. CONCLUSION: These results demonstrated the ease of which spiral DENSE MRI could be applied to clinical studies because of the shortened imaging time, while quantifying realistic cartilage deformations that occur through daily activities and that could serve as biomarkers of early osteoarthritis.

Increased adiposity is associated with altered skeletal muscle energetics.

The objective of this pilot study was to characterize relationships between skeletal muscle energy metabolism and body composition in healthy adults with varied amounts and distribution of adipose tissue. In vivo muscle energetics were quantified using dynamic 31P magnetic resonance spectroscopy with knee extension exercise standardized to subject lean body mass. Spearman's correlation analysis examined relationships between muscle metabolism indices and measures of adiposity including body mass index (BMI), total body fat, and quadriceps intermuscular adipose tissue (IMAT). Post hoc partial correlations were examined controlling for additional body composition measures. Kruskal-Wallis tests with Dunn-Sidak post hoc comparisons evaluated group differences in energy metabolism based on body composition profiles (i.e., lean, normal-weight obese, and overweight-obese) and IMAT tertiles. BMI negatively correlated with end-exercise muscle pH after correcting for IMAT and total body fat (r = -0.46, P = 0.034). Total adiposity negatively correlated with maximum oxidative capacity after correcting for IMAT (r = -0.54, P = 0.013). IMAT positively correlated with muscle proton buffering capacity after correcting for total body fat (r = 0.53, P = 0.023). Body composition groups showed differences in end-exercise fall in [PCr] with normalized workload (P = 0.036; post hoc: overweight-obese < lean, P = 0.029) and maximum oxidative capacity (P = 0.021; post hoc: normal-weight obese < lean, P = 0.016). IMAT tertiles showed differences in end-exercise fall in [PCr] with normalized workload (P = 0.035; post hoc: 3rd < 1st, P = 0.047). Taken together, these results support increased adiposity is associated with reduced muscle energetic efficiency with more reliance on glycolysis, and when accompanied with reduced lean mass, is associated with reduced maximum oxidative capacity.NEW & NOTEWORTHY Skeletal muscle energy production is influenced by both lean body mass and adipose tissue but the effect of their distribution on energy metabolism is unclear. This study examined variations in quadriceps muscle energy metabolism in healthy adults with varied relative amounts of lean and adipose tissue. Results suggest increased adiposity is associated with reduced muscle energetic efficiency with more reliance on glycolysis, and when accompanied with reduced lean mass, is associated with reduced maximum oxidative capacity.

Genicular Nerve Ablation Review Using Cooled-Radiofrequency Nerve Ablation.

Osteoarthritis (OA) is globally the most prevalent joint disease and causes patients great pain, limited joint mobility, and psychological distress. Short- and long-term therapies like steroid injections and arthroplasty exist, respectively. Joint arthroplasty can effectively treat symptomatic end-stage OA, but most patients do not go through with surgery because they are not qualified, have comorbidities, or do not wish to undergo surgery. As a result, patients can turn to opioid agonists for pain relief, which contributes to the growing opioid epidemic that mars our communities. Cooled radiofrequency ablation (C-RFA) is an effective treatment modality that can alleviate the pain associated with moderate to severe OA, especially in patients who have tried and failed conservative therapy. This review article elucidates the benefits of C-RFA, while also walking through the technical steps to performing the procedure. For patients suffering from debilitating joint OA, especially of the knee, C-RFA is a minimally invasive procedure that ensures pain relief.

Does Postoperative Spine Infection Bacterial Gram Type Affect Surgical Debridement or Antibiotic Duration?

STUDY DESIGN: This is a retrospective cohort study. OBJECTIVE: The aim was to evaluate differences in readmission rates, number of debridements, and length of antibiotic therapy when comparing bacterial gram type following lumbar spinal fusion infections. SUMMARY OF BACKGROUND DATA: Surgical site infections (SSIs) after spinal fusion serve as a significant source of patient morbidity. It remains to be elucidated how bacterial classification of the infecting organism affects the management of postoperative spinal SSI. METHODS: Patients who underwent spinal fusion with a subsequent diagnosis of SSI between 2013 and 2019 were retrospectively identified. Patients were grouped based on bacterial infection type (gram-positive, gram-negative, or mixed infections). Poisson regressions analyzed the relationship between the type of bacterial infection and the number of irrigation and debridement (I&D) reoperations, and the duration of intravenous (IV) antibiotic therapy. Significance was set at P <0.05. RESULTS: Of 190 patients, 92 had gram-positive (G+) infections, 57 had gram-negative (G-) infections, and 33 had mixed (M) infections. There was no difference in 30 or 90-day readmissions for infection between groups (both P =0.051). Patients in the M group had longer durations of IV antibiotic treatment (G+: 46.4 vs. G-: 41.0 vs. M: 55.9 d, P =0.002). Regression analysis demonstrated mixed infections were 46% more likely to require a greater number of debridements ( P =0.001) and 18% more likely to require an increased duration of IV antibiotic therapy ( P <0.001), while gram-negative infections were 10% less likely to require an increased duration of IV antibiotic therapy ( P <0.001) when compared with G- infections. CONCLUSION: Spinal SSI due to a mixed bacterial gram type results in an increased number of debridements and a longer duration of IV antibiotics required to resolve the infection compared with gram-negative or gram-positive infections. LEVEL OF EVIDENCE: Level III.

Sex differences in the relationships between body composition, fat distribution, and mitochondrial energy metabolism: a pilot study.

BACKGROUND: Adiposity and mitochondrial dysfunction are related factors contributing to metabolic disease development. This pilot study examined whether in vivo and ex vivo indices of mitochondrial metabolism were differentially associated with body composition in males and females. METHODS: Thirty-four participants including 19 females (mean 27 yr) and 15 males (mean 29 yr) had body composition assessed by dual energy x-ray absorptiometry and magnetic resonance (MR) imaging. Monocyte reserve capacity and maximal oxygen consumption rate (OCR) were determined ex vivo using extracellular flux analysis. In vivo quadriceps mitochondrial function was measured using 31P-MR spectroscopy based on post-exercise recovery kinetics (τPCr). The homeostatic model assessment of insulin resistance (HOMA-IR) was calculated from fasting glucose and insulin levels. Variables were log-transformed, and Pearson correlations and partial correlations were used for analyses. RESULTS: Mitochondrial metabolism was similar between sexes (p > 0.05). In males only, higher fat mass percent (FM%) was correlated with lower reserve capacity (r = - 0.73; p = 0.002) and reduced muscle mitochondrial function (r = 0.58, p = 0.02). Thigh subcutaneous adipose tissue was inversely related to reserve capacity in males (r = - 0.75, p = 0.001), but in females was correlated to higher maximal OCR (r = 0.48, p = 0.046), independent of FM. In females, lean mass was related to greater reserve capacity (r = 0.47, p = 0.04). In all participants, insulin (r = 0.35; p = 0.04) and HOMA-IR (r = 0.34; p = 0.05) were associated with a higher τPCr. CONCLUSIONS: These novel findings demonstrate distinct sex-dependent associations between monocyte and skeletal muscle mitochondrial metabolism with body composition. With further study, increased understanding of these relationships may inform sex-specific interventions to improve mitochondrial function and metabolic health.

What Is the Impact of Smoking on Patient-Reported Outcomes Following Posterior Cervical Decompression and Fusion?

OBJECTIVE: The purpose of this retrospective cohort study was to investigate the impact of smoking on patient-reported outcome measures (PROMs) following elective posterior cervical decompression and fusion (PCF). METHODS: Electronic medical records at a single institution were reviewed for patients undergoing elective PCF. Patients were grouped based on smoking history: current smokers, former smokers, and never smokers. A delta score (Δ) was calculated for all PROMs (postoperative minus preoperative scores). Continuous and categorical data were compared using analysis of variance or χ2 tests. Regression analysis controlled for demographics. Patients were then regrouped into current smokers and nonsmokers for reanalysis. RESULTS: A total of 195 patients were included, of whom 35 (22.1%) were current smokers, 51 (26.2%) were former smokers, and 101 (51.8%) were never smokers. Preoperative and postoperative Short-Form 12 Mental Component Score (MCS-12) were significantly lower in the current smoker group (preoperative: current 42.7, former 49.9, and never 46.6; P = 0.024; postoperative: current 44.6, former 53.7, and never 52.2; P = 0.003). Only never smokers improved in MCS-12 and Neck Disability Index following surgery. On regrouping, current smokers had significantly lower preoperative MCS-12 (42.7 vs. 47.7, P = 0.031), lower preoperative modified Japanese Orthopaedic Association (12.2 vs. 14.0, P = 0.039), greater preoperative visual analog scale Arm (6.39 vs. 4.94, P = 0.025), and lower postoperative MCS-12 (44.6 vs. 52.7, P = 0.001). Only the nonsmokers improved in MCS-12 and Neck Disability Index following surgery. On regression analysis, smoking was not an independent predictor of ΔPROMs. CONCLUSIONS: Univariate analysis found that smokers have worse symptoms at baseline. However, smoking status was not an independent predictor of improvement in ΔPROMs following elective PCF.

Brain Activity During Experimental Knee Pain and Its Relationship With Kinesiophobia in Patients With Patellofemoral Pain: A Preliminary Functional Magnetic Resonance Imaging Investigation.

CONTEXT: The etiology of patellofemoral pain has remained elusive, potentially due to an incomplete understanding of how pain, motor control, and kinesiophobia disrupt central nervous system functioning. OBJECTIVE: To directly evaluate brain activity during experimental knee pain and its relationship to kinesiophobia in patients with patellofemoral pain. DESIGN: Cross-sectional. METHODS: Young females clinically diagnosed with patellofemoral pain (n = 14; 14.4 [3.3] y; body mass index = 22.4 [3.8]; height = 1.61 [0.1] m; body mass = 58.4 [12.7] kg). A modified Clarke test (experimental pain condition with noxious induction via patella pressure and quadriceps contraction) was administered to the nondominant knee (to minimize limb dominance confounds) of patients during brain functional magnetic resonance imaging (fMRI) acquisition. Patients also completed a quadriceps contraction without application of external pressure (control contraction). Kinesiophobia was measured using the Tampa Scale of Kinesiophobia. The fMRI analyses assessed brain activation during the modified Clarke test and control contraction and assessed relationships between task-induced brain activity and kinesiophobia. Standard processing for neuroimaging and appropriate cluster-wise statistical thresholds to determine significance were applied to the fMRI data (z > 3.1, P < .05). RESULTS: The fMRI revealed widespread neural activation in the frontal, parietal, and occipital lobes, and cerebellum during the modified Clarke test (all zs > 4.4, all Ps < .04), whereas neural activation was localized primarily to frontal and cerebellar regions during the control contraction test (all zs > 4.4, all Ps < .01). Greater kinesiophobia was positively associated with greater activity in the cerebello-frontal network for the modified Clarke test (all zs > 5.0, all Ps < .01), but no relationships between kinesiophobia and brain activity were observed for the control contraction test (all zs < 3.1, all Ps > .05). CONCLUSIONS: Our novel experimental knee pain condition was associated with alterations in central nociceptive processing. These findings may provide novel complementary pathways for targeted restoration of patient function.

Pilot study for treatment of symptomatic shoulder arthritis utilizing cooled radiofrequency ablation: a novel technique.

OBJECTIVE: To introduce cooled radiofrequency nerve ablation (C-RFA) as an alternative to managing symptomatically moderate to severe glenohumeral osteoarthritis (OA) in patients who have failed other conservative treatments and who are not surgical candidates or refuse surgery. MATERIAL AND METHODS: This prospective pilot study includes a total of 12 patients experiencing chronic shoulder pain from moderate to severe glenohumeral OA. Patients underwent anesthetic blocks of the axillary, lateral pectoral, and suprascapular nerves to determine candidacy for C-RFA treatment. Adequate response after anesthetic block was over 50% immediate pain relief. Once patients were deemed candidates, they underwent C-RFA of the three nerves 2-3 weeks later. Treatment response was evaluated using the clinically validated American Shoulder and Elbow Surgeons (ASES) score and visual analog scale (VAS) to assess pain, stiffness, and functional activities of daily living. Follow-up outcome scores were collected up to 6 months after C-RFA procedure. RESULTS: Twelve patients underwent C-RFA procedure for shoulder OA. VAS scores significantly improved from 8.8 ± 0.6 to 2.2 ± 0.4 6 months after the C-RFA treatment (p < 0.001). Patient's ASES score results significantly improved in total ASES from 17.2 ± 6.6 to 65.7 ± 5.9 (p < 0.0005). No major complications arose. No patients received re-treatment or underwent shoulder arthroplasty. CONCLUSION: Image-guided axillary, lateral pectoral, and suprascapular nerve C-RFA has minimal complications and is a promising alternative to treat chronic shoulder pain and stiffness from glenohumeral arthritis.

Alternative treatment of hip pain from advanced hip osteoarthritis utilizing cooled radiofrequency ablation: single institution pilot study.

OBJECTIVE: To establish the effectiveness of cooled radiofrequency ablation in managing hip pain from osteoarthritis at 6 months after receiving treatment in patients who failed conservative treatments and are not surgical candidates due to comorbidities or unwillingness to undergo arthroplasty surgery by targeting the femoral and obturator branches and assessing the degree of hip pain relief and change of function. MATERIALS AND METHODS: This prospective pilot study includes a total of 11 consecutive patients experiencing persistent chronic hip pain in the setting of advanced osteoarthritis. Patients initially underwent anesthetic blocks of the obturator and femoral nerve branches to determine cooled radiofrequency ablation candidacy. After adequate response to the anesthetic blocks (> 50% immediate pain relief), patients were subjected to the procedures 2-3 weeks later. Treatment response was evaluated utilizing clinically validated questionnaires and visual analog score in order to assess impact on pain severity, stiffness, and functional activities of daily living. Follow-up outcome scores were collected up to 6 months after cooled radiofrequency ablation procedure. RESULTS: A total of 11 hips were treated consecutively between August 2019 and March 2020 (mean patient age 61.4 years; 8 M:3F). The mean total HOOS score improved significantly from baseline at 17.0 ± 6.0 to 52.9 ± 5.4 at a mean of 6.2 months after treatment (p < 0.0001), with significant improvement in mean pain score from 16.1 ± 6.6 to 53.4 ± 7.4 (p < 0.0001) and mean stiffness score from 15.0 ± 8.1 to 53.6 ± 11.0 (p < 0.0001). No major complications were encountered. No patients went on to re-treatment, surgery, or other intervention. CONCLUSION: Image-guided obturator and femoral nerve cooled radiofrequency ablation is effective and safe in treating chronic hip pain/stiffness in the setting of advanced osteoarthritis.

Intravoxel Incoherent Motion Magnetic Resonance Imaging in Skeletal Muscle: Review and Future Directions.

Throughout the body, muscle structure and function can be interrogated using a variety of noninvasive magnetic resonance imaging (MRI) methods. Recently, intravoxel incoherent motion (IVIM) MRI has gained momentum as a method to evaluate components of blood flow and tissue diffusion simultaneously. Much of the prior research has focused on highly vascularized organs, including the brain, kidney, and liver. Unique aspects of skeletal muscle, including the relatively low perfusion at rest and large dynamic range of perfusion between resting and maximal hyperemic states, may influence the acquisition, postprocessing, and interpretation of IVIM data. Here, we introduce several of those unique features of skeletal muscle; review existing studies of IVIM in skeletal muscle at rest, in response to exercise, and in disease states; and consider possible confounds that should be addressed for muscle-specific evaluations. Most studies used segmented nonlinear least squares fitting with a b-value threshold of 200 sec/mm2 to obtain IVIM parameters of perfusion fraction (f), pseudo-diffusion coefficient (D*), and diffusion coefficient (D). In healthy individuals, across all muscles, the average ± standard deviation of D was 1.46 ± 0.30 × 10-3  mm2 /sec, D* was 29.7 ± 38.1 × 10-3  mm2 /sec, and f was 11.1 ± 6.7%. Comparisons of reported IVIM parameters in muscles of the back, thigh, and leg of healthy individuals showed no significant difference between anatomic locations. Throughout the body, exercise elicited a positive change of all IVIM parameters. Future directions including advanced postprocessing models and potential sequence modifications are discussed. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY: Stage 2.

Comparison of Outcomes Including or Excluding the Level of Listhesis After ACDF in the Setting of Degenerative Spondylolisthesis.

STUDY DESIGN: This was a retrospective cohort study. OBJECTIVE: The goal of this study is to evaluate the outcomes of patients with cervical degenerative spondylolisthesis (DS) undergoing anterior cervical discectomy and fusion (ACDF), specifically comparing surgeries that include versus exclude the DS level. SUMMARY OF BACKGROUND DATA: DS has been extensively studied in the lumbar spine associated with both back and leg pain leading to worse patient quality of life measures. Conversely, there is a relative dearth of literature regarding surgical and clinical outcomes in the setting of cervical DS. MATERIALS AND METHODS: A total of 315 patients undergoing ACDF between 2014 and 2018 with minimum of 1-year postoperative patient-reported outcome measures (PROMs) were retrospectively reviewed. Forty-six patients were found to have DS and were categorized based on whether an ACDF was performed at the same level (SL) or at a different level (DL) than the spondylolisthesis. Patient demographics, surgical parameters, preoperative and postoperative radiographs, and PROMs were compared between groups. RESULTS: Of the 315 patients, a total of 46 met the inclusion criteria including 21 SL and 25 DL patients. There were no significant differences in patient demographics between the groups. The SL cohort had a significantly worse preoperative sagittal vertical axis (SL: 34.4 vs. 26.1, P=0.025) but no difference in postoperative or delta sagittal vertical axis. Both patient cohorts reported significant postoperative improvement in all PROMs, except Short-Form 12 Mental Component Score in the SL group. There were no differences between the groups regarding Visual Analog Scale Neck, Visual Analog Scale Arm, Neck Disability Index, or Short-Form 12 Physical Component Score. Regression analysis demonstrated SL to be a significant negative predictor for improvement in Short-Form 12 Mental Component Score (ß: -11.27, P=0.10). CONCLUSION: Patients treated only at their neurologically symptomatic levels, excluding asymptomatic listhesis in their construct, can expect equivalent radiographic as well as physical function, disability, and pain outcomes 1 year after ACDF compared with patients whose listhetic level was included in their construct. LEVEL OF EVIDENCE: Level III.

Cervical Alignment and Proximal and Distal Junctional Failure in Posterior Cervical Fusion: A Multicenter Comparison of 2 Surgical Approaches.

STUDY DESIGN: This was a multicenter retrospective cohort study. OBJECTIVE: The purpose of this study was to compare the surgical and radiographic outcomes of patients undergoing posterior cervical fusion (PCF) with constructs extending from C2 to T2 to patients with constructs extending from C3 to T1. SUMMARY OF BACKGROUND DATA: Limited evidence exists regarding the appropriate level of proximal and distal extension of PCF constructs. METHODS: A multicenter retrospective cohort study of patients who underwent PCF between 2012 and 2020 was performed. Surgical and radiographic outcomes were compared between those who had C3-T1 or C2-T2 constructs. RESULTS: A total of 155 patients were included in the study (C2-T2: 106 patients, C3-T1: 49 patients). There were no significant differences in demographics or preoperative symptoms between cohorts. Fusion rates were significantly higher in the C2-T2 (93%) than the C3-T1 (80%, P=0.040) cohort. When comparing the C2-T2 to the C3-T1 cohort, the C3-T1 cohort had a significantly greater rate of proximal junctional failure (2% vs. 10%, P=0.006), distal junctional failure (1% vs. 20%, P<0.001) and distal screw loosening (4% vs. 15%, P=0.02). Although ∆C2-C7 sagittal vertical axis increased significantly in both cohorts (C2-T2: 6.2 mm, P=0.04; C3-T1: 8.4 mm, P<0.001), correction did not significantly differ between groups (P=0.32). The C3-T1 cohort had a significantly greater increase in ∆C2 slope (8.0 vs. 3.1 degrees, P=0.03) and ∆C0-C2 Cobb angle (6.4 vs. 1.2 degrees, P=0.04). CONCLUSION: In patients undergoing PCF, a C2-T2 construct demonstrated lower rates of pseudarthrosis, distal junctional failure, proximal junctional failure, and compensatory upper cervical hyperextension compared with a C3-T1 construct.

Patients With Preoperative Cervical Deformity Experience Similar Clinical Outcomes to Those Without Deformity Following 1-3 Level Anterior Cervical Decompression and Fusion.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: The aim was to compare the outcomes of patients with incompletely corrected cervical deformity against those without deformity following short-segment anterior cervical decompression and fusion for clinically significant radiculopathy or myelopathy. SUMMARY OF BACKGROUND DATA: Cervical deformity has increasingly been recognized as a driver of disability and has been linked to worse patient-reported outcomes measures (PROMs) after surgery. METHODS: Patients 18 years or above who underwent 1-3 level anterior cervical decompression and fusion to address radiculopathy and/or myelopathy at a single institution between 2014 and 2018 with at least 1 year of PROMs were reviewed. Patients were categorized based on cervical deformity into 2 groups: sagittal vertebral axis (cSVA) ≥40 mm as the deformity group, and cSVA <40 mm as the nondeformity group. Patient demographics, surgical parameters, preoperative and postoperative radiographs, and minimum 1-year PROMs were compared. RESULTS: Of the 230 patients, 191 (83%) were in the nondeformity group and 39 (17%) in the deformity group. Patients with deformity were more likely to be male (69.2% vs. 40.3%, P<0.001) and have a greater body mass index (32.8 vs. 29.7, P=0.028). The deformity group had significantly greater postoperative cSVA (44.2 vs. 25.1 mm, P<0.001) but also had significantly greater ∆cSVA (-4.87 vs. 0.25 mm, P=0.007) than the nondeformity group. Both groups had significant improvements in visual analog scale arm, visual analog scale neck, Short-Form 12 Physical Component Score, and neck disability index (NDI) (P<0.001). However, the deformity group experienced significantly greater ∆NDI and ∆mental component score (MCS)-12 scores (-19.45 vs. -11.11, P=0.027 and 7.68 vs. 1.32, P=0.009). CONCLUSIONS: Patients with preoperative cervical sagittal deformity experienced relatively greater improvements in NDI and MCS-12 scores than those without preoperative deformity. These results suggest that complete correction of sagittal alignment is not required for patients to achieve significant clinical improvement. LEVEL OF EVIDENCE: III.

Sagittal alignment differences on the operating room table compared to preoperative and postoperative imaging in anterior cervical discectomy and fusion.

Study Design: The study design used was a retrospective cohort. Objective: The objective of this study is to determine if intraoperative improvements in sagittal alignment on the operating table persisted on postoperative standing radiographs. Summary of Background Data: Cervical sagittal alignment may be correlated to postoperative outcomes. Since anterior cervical discectomy and fusions (ACDFs) can restore some cervical lordosis through intervertebral grafts/cages, it is important to understand if intraoperative radiographic measurements correlate with persistent postoperative radiographic changes. Materials and Methods: Patients undergoing elective primary ACDF were screened for the presence of lateral cervical radiographs preoperatively, intraoperatively, and postoperatively. Patients were excluded if their first postoperative radiograph was more than 3 months following the procedure or if cervical lordosis was not able to be measured at each time point. Paired t-tests were utilized to compare differences in measurements between time points. Statistical significance was set at P < 0.05. Results: Of 46 included patients, 26 (56.5%) were female, and the mean age was 55.2 ± 11.6 years. C0-C2 lordosis significantly increased from the preoperative to intraoperative time point (delta [Δ] = 4.49, P = 0.029) and significantly decreased from the intraoperative to postoperative time period (Δ = -6.57, P < 0.001), but this resulted in no significant preoperative to postoperative change (Δ = -2.08, P = 0.096). C2 slope decreased from the preoperative to the intraoperative time point (Δ = -3.84, P = 0.043) and significantly increased from the intraoperative to the postoperative time point (Δ = 3.68, P = 0.047), which also resulted in no net change in alignment between the preoperative and postoperative periods (Δ = -0.16, P = 0.848). There was no significant difference in the C2-C7 SVA from the preoperative to intraoperative (Δ = 0.85, P = 0.724) or intraoperative to postoperative periods (Δ = 2.04, P = 0.401); however, the C2-C7 SVA significantly increased from the preoperative to postoperative period (Δ = 2.88, P = 0.006). Conclusions: Intraoperative positioning predominantly affects the mobile upper cervical spine, particularly C0-C2 lordosis and C2 slope, but these changes do not persist postoperatively.

Review of Extraosseous Applications of Thermal Ablation in the Treatment of Moderate to Severe Large Joint Osteoarthritis.

Osteoarthritis (OA) is the most common joint disease worldwide, leading to significant pain, restricted range of motion, and disability. A gap exists between short- and long-term symptom-relieving therapies. Although arthroplasty is an effective treatment for symptomatic end-stage disease, most patients ultimately do not receive a joint replacement due to suboptimal surgical qualifications, comorbidities, or an aversion to surgery. The lack of additional treatment options in this setting makes opioid agonists a commonly used pharmacologic agent, contributing to the addiction epidemic that greatly afflicts our communities. Cooled radiofrequency ablation (CRFA) has arisen as a treatment modality in the setting of moderate to severe OA among patients refractory to conservative management, generally showing greater efficacy compared with other existing strategies. This review focuses on the benefits of CRFA and its technical feasibility as a management option among patients experiencing debilitating large joint OA with limited clinical options.

Contribution of Intramyocellular Lipids to Decreased Computed Tomography Muscle Density With Age.

Skeletal muscle density, as determined by computed tomography (CT), has been shown to decline with age, resulting in increased frailty and morbidity. However, the mechanism underlying this decrease in muscle density remains elusive. We sought to investigate the role of intramyocellular lipid (IMCL) accumulation in the age-related decline in muscle density. Muscle density was measured using computerized tomography (CT), and IMCL content was quantified using in vivo proton magnetic resonance spectroscopy (1H-MRS). The study population consisted of 314 healthy participants (142 men, 32-98 years) of the Baltimore Longitudinal Study of Aging (BLSA). In addition to IMCL quantification, obesity-related covariates were measured, including body mass index (BMI), waist circumference, and circulating triglyceride concentration. Higher IMCL concentrations were significantly correlated with lower muscle density in older individuals, independent of age, sex, race, and the obesity-associated covariates (p < 0.01). Lower muscle density was also significantly associated with greater age-adjusted IMCL, a variable we constructed using LOESS regression (p < 0.05). Our results suggest that the accumulation of IMCL may be associated with a decrease in muscle density. This may serve to define a potential therapeutic target for treatment of age-associated decreased muscle function.