Effectiveness of orthopedic implant removal surgery in patients with no implant-related symptoms after fracture union of isolated lower extremity shaft fractures: patient-centered evaluation.

INTRODUCTION: Routine orthopedic implant removal surgery (OIRS) in patients with no implant-related symptoms after union is controversial. Various factors, such as various fracture sites, fracture types, and accompanying fractures at other sites, act as error variables in the evaluation of routine OIRS. The purpose of this study is to evaluate the benefits of orthopedic implant removal surgery (OIRS) in patients with no implant-related symptoms such as infection and soft tissue irritation after union of isolated lower extremity shaft fractures from a patient-centered evaluation MATERIALS AND METHODS: Eighty-four patients who achieved fracture union after internal fixation of femoral shaft or tibial shaft fractures (March 2004 to December 2018) and who showed no implant-related symptoms were evaluated retrospectively. Minimum post-OIRS follow-up period was 1 year. Thirty-eight patients were treated with intramedullary nail and 13 were treated with plate and screws for femoral shaft fracture. Twenty patients were treated with intramedullary nail and 13 were treated with plate and screws for tibial shaft fracture. All patients subsequently underwent OIRS. Quality of life (QoL) and lower extremity pain using visual analogue scale (VAS) were evaluated 1 day before OIRS. Patient satisfaction with the OIRS, VAS, and QoL were assessed at least 1 year after OIRS using the SF-36 questionnaire. RESULTS: The physical component score, mental component score, and scores of all eight domains showed significant improvement after OIRS (p < 0.01). Patients with femoral shaft fractures tended to have lower pre- and post-OIRS SF-36 scores than those with tibial shaft fracture. Among patients with femoral shaft fracture, SF-36 scores were comparable in the nail and plate groups. Among patients with tibial shaft fracture, nail group showed relatively better QoL than the plate group, before and after OIRS in spite of several complications such as formation of scar tissue, nerve damage, and refracture. CONCLUSIONS: Patients with no implant-related symptoms showed significant improvement in QoL and satisfaction after OIRS. This suggests that OIRS is beneficial from the patients' evaluation. LEVEL OF EVIDENCE: Therapeutic Level II.

Biomechanical Analysis of Three Different Reconstruction Techniques for Scapholunate Instability: A Cadaveric Study.

Background: This study aimed to compare the biomechanical strength of 360° scapholunate interosseous ligament (SLIL) reconstruction only using an artificial material (AM), double dorsal limb (DDL) SLIL reconstruction only using AM, and the modified Brunelli technique (MBT) with ligament. Methods: Eight cadaver wrists were used for this study. The SL interval, SL angle, and radiolunate (RL) angle were recorded with MicroScribe. The SL distance was measured after dividing the volar and dorsal aspects. We utilized four different wrist postures (neutral, flexion, extension, and clenched fist) to compare five conditions: intact wrist, SLIL resection, 360° SLIL reconstruction using AM, DDL SLIL reconstruction using AM, and MBT SLIL reconstruction with ligament. Results: The dorsal SL distance in the SLIL resection was widened in all wrist positions. The dorsal SL distance was restored with all three techniques and in all wrist positions. The volar SL distance in the wrist extension position was widened in the SLIL resection condition. The volar SL distance was restored in the extension position after 360° SLIL reconstruction using AM condition. There were no statistically significant differences in SL and RL angles among the conditions. Conclusions: All three reconstruction techniques could restore the dorsal SL distance. However, only the 360° SLIL reconstruction using AM restored the volar SL distance in the wrist extension position. DDL SLIL reconstruction using AM tended to overcorrect, whereas 360° SLIL reconstruction using AM effectively stopped volar SL interval widening.

Electrostatically Controllable Channel Thickness and Tunable Low-Frequency Noise Characteristics of Double-Gated Multilayer MoS2 Field-Effect Transistors with h-BN Dielectric.

Two-dimensional transition-metal dichalcogenide (TMD) materials have attracted increasing attention in efforts to overcome fundamental issues faced by the complementary metal-oxide-semiconductor industry. Multilayer TMD materials such as MoS2 can be used for high-performance transistor-based applications; the drive currents are high and the materials handle low-frequency (LF) noise well. We fabricated double-gated multilayer MoS2 transistors using the h-BN dielectric for the top gate and silicon dioxide for the bottom gate. We systemically investigated the bottom gate voltage (Vb)-controlled electrical characteristics and the top/bottom interface-coupling effects. The effective thickness of the MoS2 channel (tMoS2_eff) was well modulated by Vb, and tMoS2_eff reduction by negative Vb dramatically improved the Ion/Ioff ratio. Numerical simulation and analytical modeling with a variation of the depletion depth under different bias conditions verified the experimental results. We were also the first to observe Vb-tuned LF noise characteristics. Here, we discuss the Vb-affected series resistance and carrier mobility in detail. Our findings greatly enhance the understanding of how double-gated multilayer MoS2 transistors operate and will facilitate performance optimization in the real world.

Comparison of Fusion Rate and Functional Outcome Between Local Cancellous Bone Plus Demineralized Bone Matrix and Local Bone in 1-Level Posterior Lumbar Interbody Fusion.

STUDY DESIGN: Retrospective study with prospectively collected data. OBJECTIVE: The purpose of this study is to investigate the difference in fusion rate and clinical outcome of patients with local bone as filler for the graft and demineralized bone matrix (DBM) plus only the cancellous bone from local bone as a filler for cage in 1-level posterior lumbar interbody fusion (PLIF) with cage. SUMMARY OF BACKGROUND DATA: Cancellous bone is more advantageous than cortical bone in the local bone for improving bone formation in spine fusion surgery. There are little studies on the difference in fusion rate and reduction of fusion time using only these cancellous bones. METHODS: Of the 40 patients who underwent 1-level PLIF using cage, 20 patients in group A used local bone and 20 patients in group B used mixture of cancellous bone extracted separately from local bone and commercially available DBM as filler for cage. Changes in fusion rate and intervertebral spacing were measured using lateral radiography, and fusion was determined as nonunion using the Brantigan-Steffee classification. The clinical outcome was evaluated. RESULTS: There was no difference in height change over time between the two groups. Regarding union grade, group B showed better union grade than group A. However, no difference in union grade change over time was observed between the 2 groups. In group B, Oswestry Disability Index (ODI), Rolland-Morris Disability Questionnaire (RMDQ), and SF-36 mental component score (MCS) significantly decreased, but there was no difference in change over time. CONCLUSIONS: In 1-level PLIF for degenerative lumbar disease, better fusion rate was observed in the group that used only cancellous bone from local bone plus DBM than that in the group that used local bone; however, there was no difference in fusion grade change over time in the 2 groups.

Usefulness of the additional contrast agents to identify offending nerve root in selective nerve root block.

ABSTRACT: It is hypothesized that if it is confirmed that the pain caused by the injection needle coincides with the lower leg radiating pain(LLRP) that the patient mainly complains of, then the contrast agents may be used less. This study aims to understand if the identification of lancinating identical pain in the procedure could replace the use of contrast agents that causes additional pain provocation using control arm of randomized clinical trial.This retrospective study included 165 patients who met exclusion criteria from among patients who underwent Selective nerve root block for the treatment of LLRP. With the identical and lancinating pain confirmed in the same site of the patient, consistent with that of the original symptom, the subjects were divided into 2 groups: 1 without contrast injection (Non-Dye [ND] group; 57 patients) and the other with contrast injection (Dye [D] group; 108 patients). The degree of LLRP in the 2 groups was evaluated using visual analog scale (VAS) before injection, 2, 6, and 12 weeks after injection. Functional outcomes were measured using Owestry Disability Index and Rolland-Morris Disability Questionnair, whereas quality of life was measured using Physical component score and Mental component score of Short Form 36 (SF-36) before injection and 3 months after injection.There was no statistically significant difference in the LLRP severity in both groups at all times and no statistical difference in the degree of VAS improvement relative to the before-injection VAS value between the 2 groups at 2 and 6 weeks after injection (all P > .05). At 12 weeks after injection, there was a statistically significant difference, but they were below Minimum Clinical Important Difference, bearing little clinical implications. There was no statistically significant difference between the 2 groups in Owestry Disability Index, Rolland-Morris Disability Questionnair, SF-36 Physical component score, and SF-36 Mental component score at every interval (all P > .05).Instead of contrast agent injections that have been used for accurate nerve root identification during Selective Nerve Root Block, the method of merely checking if the needle-induced pain under fluoroscopic imaging is consistent with the LLRP that the patient predominantly experiences shows the same effect in the patient's pain control and functional outcome.

Effects of vitamin D supplementation on the functional outcome in patients with osteoporotic vertebral compression fracture and vitamin D deficiency.

BACKGROUND: In osteoporotic vertebral compression fractures, supplementation using vitamin D preparations and maintenance of blood vitamin D level within the normal range are necessary for proper fracture union, enhancement of muscle strength, and maintenance of body balance. The purpose of this study is to investigate the effects of vitamin D supplementation on blood vitamin D level, pain relief, union time, and functional outcome in patients with osteoporotic vertebral compression fracture and vitamin D deficiency. METHODS: One hundred thirty patients who were deficient in blood vitamin D level and had osteoporotic vertebral compression fracture were divided into supplementation group and non-supplementation group. Initially, 3 months, 6 months, and 12 months after the injury, radiographs were taken to assess fracture union, and questionnaires were evaluated to evaluate the functional outcome and quality of life. RESULTS: The mean age of the 130 patients (36 males and 94 females) was 74.75 ± 7.25 years. There were no statistically significant differences in initial severity of low back pain, functional outcome, and quality of life between the insufficient group and the deficient group (all p values were > 0.05). There was no significant time-by-group interaction between the supplementation group and the non-supplementation group (p = 0.194). In terms of SF-36 physical component score, there was no significant time-by-group interaction between the supplementation group and the non-supplementation group (p = 0.934). CONCLUSIONS: Fracture union was achieved in all patients regardless of serum vitamin D level, and there were significant improvements in severity of low back pain, functional outcome, and quality of life over 12 months in patients with osteoporotic vertebral compression fracture. Short-term vitamin D supplementation of patients with osteoporotic vertebral compression fracture and deficiency of vitamin D did not result in significant differences in fracture union status, functional outcome, and quality of life between the supplementation groups and the non-supplementation groups of patients.

Kinematic analysis of two scapholunate ligament reconstruction techniques.

PURPOSE: This study compares the kinematic changes after the procedures for scapholunate interosseous ligament (SLIL) reconstruction-the modified Brunelli technique (MBT) and Mark Henry's technique (MHT). METHODS: Ten cadaveric wrists were used. The scapholunate (SL) interval and angle and radiolunate (RL) angle were recorded using the MicroScribe system. The SL interval was measured by dividing the volar and dorsal portions. Four motions of the wrist were performed-neutral, flexion, extension, and clenched fist (CF) positions-and compared among five conditions: (1) intact wrist, (2) volar SLIL resection, (3) whole SLIL resection, (4) MBT reconstruction, and (5) MHT reconstruction. RESULTS: Under the whole SLIL resection condition, the dorsal SL intervals were widened in all positions. In all positions, the dorsal SL intervals were restored after MBT and MHT. The volar SL interval widened in the extension position after volar SLIL resection. The volar SL interval was not restored in the extension position after MBT and MHT. The SL angle increased in the neutral and CF positions under the whole SLIL resection condition. The SL angle was not restored in the neutral and CF positions after MBT and MHT. The RL angle increased in the neutral and CF positions under the whole SLIL resection condition. The RL angle was not restored in the neutral and CF positions after MBT and MHT. CONCLUSION: The MBT and MHT may restore the dorsal SL interval. No significant differences in restoration of the SL interval between MBT and MHT were found in the cadaveric models. CLINICAL RELEVANCE: No significant differences between MBT and MHT were found in the cadaveric models for SLIL reconstruction. When considering the complications due to volar incision and additional procedures in MHT, MBT may be a more efficient technique in terms of operative time and injury of the anterior structures during surgery, but further research is needed.

Comparison of the effects of corticosteroid and hyaluronic acid-carboxymethylcellulose solution on selective nerve root block for lumbar radiculopathy: A prospective, double-blind, randomized controlled clinical trial.

BACKGROUND: Selective nerve root block (SNRB) was shown to effectively control radiating pain and reduce the need for surgical intervention. However, repetitive injections may trigger corticosteroid-induced side effects (hypercorticism, hyperglycemia, or fluid retention). This study aims to compare the potency of hyaluronic acid-carboxymethylcellulose (HA-CMC) solution versus that of corticosteroids regarding lower leg radiating pain (LLRP) improvement and functional outcome. METHODS: Among 128 patients, 44 patients who complain about having LLRP due to lumbar spinal stenosis and do not have neurological symptoms requiring surgery were enrolled for this study. Group A with 22 patients injected with cocktail A (local anesthetics and corticosteroid) and group B with 22 patients injected with cocktail B (local anesthetics and HA-CMC). Outcome measures were the visual analog scale (VAS), Oswestry Disability Index (ODI), and short form-36 (SF-36). All patients were asked to fill in the questionnaires during the follow-up assessment period at 3 days, 7 days, 2 weeks, 6 weeks, and 12 weeks. RESULTS: In all time periods, there were no statistical differences between the two groups for VAS scores and VAS improvement over time, ODI scores and ODI improvement over time, and SF-36 PCS scores and SF-36 mental component score scores. Additionally, the 95% confidence interval of the difference in VAS score improvement between the 2 groups in all time periods was within VAS 5.0, which is the minimum clinically relevant difference. CONCLUSIONS: Considering the adverse effects of corticosteroids, and the similar LLRP improvements, functional outcome, and quality of life, the HA-CMC solution may be an alternative option to corticosteroid in SNRB.

Results of Primary Total Hip Arthroplasty Using 36 mm Femoral Heads on 1st Generation Highly Cross Linked Polyethylene in Patients 50 Years and Less with Minimum Five Year Follow-up.

PURPOSE: We evaluated the clinical and radiographic midterm results of primary total hip arthroplasty (THA) using a 36 mm diameter femoral head on 1st generation highly cross-linked polyethylene (HXLPE) in patients 50 years and less with minimum five year follow-up. MATERIALS AND METHODS: We retrospectively reviewed 31 patients (41 hips) aged 50 years and less underwent primary THA with a 36 mm diameter femoral head on HXLPE between 2004 and 2010. Clinical follow-ups included specific measurements like modified Harris hip scores (HHS) and Merle d'Aubigne and Postel score. For radiologic evaluations, together with position of acetabular cup at six weeks later of postoperation, we separately calculated the penentrations of femoral head into polyethylene liners during postoperation and one year later check-ups, and during one year later check-ups and final check-ups. RESULTS: There were no major complications except for one case of dislocation. Average modified HHS at final follow-up was 88 (81-98), and Merle d'Aubigne and Postel scores were more than 15. Mean acetabular cup inclination and anteversion were 45.81°(36.33°-54.91°) and 13.26°(6.72°-27.71°), respectively. Average femoral head penetration of steady-state wear rate determined using radiographs taken at one-year postoperatively and at latest follow-up was 0.042±0.001 mm/year. CONCLUSION: Based on minimum 5 years clinical results, we think 36 mm metal head coupling with HXLPE as the good alternate articulation surface when planning THA for patients aged 50 years and less.