Three-dimensional motion analysis of pre- and postoperative thumb movement in trapeziometacarpal joint osteoarthritis-Comparison of arthrodesis and trapeziectomy with suspensionplasty

Trapeziometacarpal osteoarthritis (TMC-OA) reduces the range of motion (ROM) of the thumb. However, the kinematic change achieved through surgical treatment remains unclear. Therefore, to quantify the kinematic change following TMC-OA surgery, we performed a three-dimensional motion analysis of the thumb using an optical motion capture system preoperatively and 1 year postoperatively in 23 patients with TMC-OA scheduled for arthrodesis (AD) or trapeziectomy with suspensionplasty (TS). Eighteen hands of nine healthy volunteers were also included as controls. Both procedures improved postoperative pain and Disability of the Arm, Shoulder and Hand scores, and AD increased pinch strength. The ROM of the base of the thumb was preserved in AD, which was thought to be due to the appearance of compensatory movements of adjacent joints even if the ROM of the TMC joint was lost. TS did not improve ROM. Quantifying thumb kinematic changes following TMC-OA surgery can improve our understanding of TMC-OA treatment and help select surgical procedures and postoperative assessment.

Differentiating Neurodegenerative Disease From Compressive Cervical Myelopathy Using Motor-Evoked Potentials

STUDY DESIGN

A retrospective case-control study.

OBJECTIVE

To differentiate neurodegenerative diseases from compressive cervical myelopathy (CCM) using motor-evoked potentials (MEPs).

SUMMARY OF BACKGROUND DATA

When considering surgery for CCM, it may be necessary to differentiate the condition from a neurodegenerative disease.

MATERIALS AND METHODS

A total of 30 healthy volunteers, 52 typical CCM patients with single-level compression of the spinal cord at C4-5 or C5-6, 7 patients with amyotrophic lateral sclerosis (ALS), and 12 patients with demyelinating disease of the central nervous system, including 11 patients with multiple sclerosis and 1 patient with neuromyelitis optica spectrum disorder, formed our study population. MEPs were recorded from the bilateral abductor digiti minimi (ADM) and abductor hallucis (AH) muscles using transcranial magnetic stimulation and electrical stimulation of the ulnar and tibial nerves. Central motor conduction time, peripheral conduction time, amplitude of MEPs, and frequency of F waves were evaluated. Receiver operating characteristic curve analysis was used to determine the cutoff value for distinguishing between CCM and ALS.

RESULTS

Significant differences were observed in the amplitude of MEPs and frequency of F waves evoked by peripheral nerve stimulation between patients with CCM and ALS. The MEP amplitude of AH was more accurate in differentiating between the two diseases compared with ADM (cutoff value, 11.2 mV, sensitivity, 87.5%; specificity, 85.7%). All 7 patients with ALS showed reduced frequency of F waves from ADM or AH, but none of the healthy volunteers or patients with other diseases demonstrated this finding. Moreover, there were no significant differences between CCM and demyelinating disease of the central nervous system in any of the assessments.

CONCLUSION

The amplitude of MEPs and frequency of F waves evoked by peripheral nerve stimulation could be helpful in differentiating ALS from CCM.

Medial meniscus extrusion during gait is associated with decrease in knee rotation in early-stage knee osteoarthritis

BACKGROUND

In patients with medial knee osteoarthritis (OA), medial meniscus extrusion during gait is aggravated by mechanical stress, such as knee adduction moment (KAM). Conversely, the decrease in the range of knee rotation during stance phase is also one of the important issues in early knee OA, whereas the correlation between medial meniscus extrusion and knee rotation during gait are unclear.

RESEARCH QUESTION

To investigate the correlation between increase in medial meniscus extrusion and range of knee rotation during gait in patients with early- and late-stage of knee OA.

METHODS

Forty patients with medial knee OA were enrolled and divided into early- and late-OA group by Kellgren-Lawrence grading scale. During gait tasks, the extent of medial meniscus extrusion was measured using ultrasonography and kinetic/kinematic data were measured using three-dimensional motion analysis system. The correlation between medial meniscus extrusion and the range of knee rotation or KAM were evaluated in the overall, early-, and late- OA groups.

RESULTS

A significant negative correlation was observed between an increase in medial meniscus extrusion and range of knee rotation angle in early-OA group only. However, an increase in medial meniscus extrusion significantly correlated with the second KAM peak in the overall and early-OA groups.

SIGNIFICANCE

The decrease in range of knee rotation during stance phase may be associated with the increase in medial meniscus extrusion during gait in patients with early knee OA.

Evaluation of the long-term patient-reported outcomes after hip arthroplasty or joint preserving with Sugioka femoral osteotomy in patients with femoral head osteonecrosis

PURPOSE

This study retrospectively evaluated long-term clinical outcomes and patient-reported outcome measures (PROMs) in patients with osteonecrosis of the femoral head (ONFH) who underwent transtrochanteric rotational osteotomy (TRO), curved varus osteotomy (CVO), and total hip arthroplasty (THA).

METHODS

We retrospectively reviewed the 109 hips in 96 patients (46 men, 50 women) who underwent CVO, TRO, or THA for ONFH treatment. The mean follow-up period for the TRO, CVO, and THA groups was 14.8, 11.5, and 13.3 years, respectively.

RESULTS

The THA conversion rate of the TRO patients was significantly higher than that of the patients with CVO, and the final clinical scores in the patients with TRO did not improve compared with preoperative scores. Postoperative PROMs showed that the total and pain scores of the patients with THA were significantly higher than those of patients with TRO and CVO, while the PROM score did not change between patients with TRO and CVO. The analysis further showed that the preoperative type C2, stage 3A, or postoperative type C1 and C2 were significant predictors of decreased final PROM scores.

CONCLUSION

This study found that CVO and THA are clinically effective treatments for ONFH, with significant improvements compared with preoperative scores. However, THA was associated with significantly higher PROMs and pain scores than those of CVO and TRO in long-term follow-up. Furthermore, our results suggest that postoperative PROMs depend mainly on the preoperative level of collapse and postoperative transposed intact ratio of the articular surface of the femoral head.

Differentiation Between Compressive Cervical and Thoracic Myelopathy Using the Central Motor Conduction Time Ratio

PURPOSE

Thoracic myelopathy is a rare condition whose diagnosis is often missed or delayed. This study aimed to differentiate between cervical and thoracic myelopathy using motor-evoked potential testing.

METHODS

The authors included 835 patients with compressive cervical myelopathy and 94 patients with compressive thoracic myelopathy. Myelopathy using motor-evoked potentials were recorded from the bilateral abductor digiti minimi and abductor hallucis muscles through transcranial magnetic stimulation. The peripheral conduction time was measured through electrical stimulation of the ulnar and tibial nerves; moreover, the central motor conduction time (CMCT) was calculated by subtracting the peripheral conduction time from the myelopathy using motor-evoked potential latency.

RESULTS

The most accurate differentiation between compressive cervical myelopathy and compressive thoracic myelopathy was achieved by the CMCT ratios (CMCT-ADM:CMCT-AH; cutoff value of 0.490, sensitivity of 83.0%, and specificity of 80.5%). After excluding patients with compressive cervical myelopathy who had spinal cord compression at C6-7, the cutoff value was 0.490, with a sensitivity of 83.0% and specificity of 87.3%.

CONCLUSIONS

Determining the CMCT ratio (cutoff value of 0.490) through motor-evoked potential testing could facilitate differentiation between compressive cervical myelopathy and compressive thoracic myelopathy.

The Relationship Between Calcaneofibular Ligament Injury and Ankle Osteoarthritis Progression: A Comprehensive Analysis of Stress Distribution and Osteophyte Formation in the Subtalar Joint

BACKGROUND

Ankle osteoarthritis (OA) mainly arises from trauma, particularly lateral ligament injuries. Among lateral ligament injuries, ankles with calcaneofibular ligament (CFL) injuries exhibit increased instability and can be a risk factor ankle OA progression. However, the relationship between CFL injury and OA progression remains unclear. Therefore, this study aims to assess the relationship between CFL injuries and ankle OA by investigating stress changes and osteophyte formation in subtalar joint.

METHODS

We retrospectively reviewed the magnetic resonance imaging (MRI) and plain radiographic evaluations of 100 ankles of 91 patients presenting with chronic ankle instability (CAI), ankle OA, or other ankle conditions. The association between CFL injuries on the oblique view of MRI and the severity of ankle OA (based on Takakura-Tanaka classification) was statistically evaluated. Additionally, 71 ankles were further subjected to CT evaluation to determine the association between the CFL injuries and the Hounsfield unit (HU) ratios of the subtalar joint and medial gutter, and the correlation between the subtalar HU ratios and osteophyte severity were statistically evaluated.

RESULTS

CFL injury was observed in 35.9% (14/39) of patients with stage 0, 42.9% (9/21) with stage 1, 50.0% (10/20) with stage 2, 100% (9/9) with stage 3a, and 90.9% (10/11) with stage 3b. CFL-injured ankles exhibited higher HU ratios in the medial gutter and lower ratios in the medial posterior subtalar joint compared to uninjured ankles. A negative correlation was observed between medial osteophyte severity and the medial subtalar joint HU ratio.

CONCLUSION

Our findings suggest that CFL injuries are common in severe ankle OA impairing the compensatory function of the subtalar joint through abnormal stress distribution and osteophyte formation.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

Dependence on visual information in patients with ACL injury for multi-joint coordination during single-leg squats: a case control study

BACKGROUND

The influence of vision on multi-joint control during dynamic tasks in anterior cruciate ligament (ACL) deficient patients is unknown. Thus, the purpose of this study was to establish a new method for quantifying neuromuscular control by focusing on the variability of multi-joint movement under conditions with different visual information and to determine the cutoff for potential biomarkers of injury risk in ACL deficient individuals.

METHODS

Twenty-three ACL deficient patients and 23 healthy subjects participated in this study. They performed single-leg squats under two different conditions: open eyes (OE) and closed eyes (CE). Multi-joint coordination was calculated with the coupling angle of hip flexion, hip abduction and knee flexion. Non-linear analyses were performed on the coupling angle. Dependence on vision was compared between groups by calculating the CE/OE index for each variable. Cutoff values were calculated using ROC curves with ACL injury as the dependent variable and significant variables as independent variables.

RESULTS

The sample entropy of the coupling angle was increased in all groups under the CE condition (P < 0.001). The CE/OE index of coupling angle variability during the descending phase was higher in ACL deficient limbs than in the limbs of healthy participants (P = 0.036). The CE/OE index of sample entropy was higher in the uninjured limbs of ACL deficient patients than in the limbs of healthy participants (P = 0.027). The cutoff value of the CE/OE index of sample entropy was calculated to be 1.477 (Sensitivity 0.957, specificity 0.478).

CONCLUSION

ACL deficient patients depended on vision to control multiple joint movements not only on the ACL deficient side but also on the uninjured side during single leg squat task. These findings underscore the importance of considering visual dependence in the assessment and rehabilitation of neuromuscular control in ACL deficient individuals.

Temporary meniscus extrusion is caused by cumulative stress from uphill and downhill tasks in healthy volunteers

Purpose

Excessive mechanical stress accumulates and causes knee injury. Meniscal extrusion is a key factor in detecting the reaction to cumulative mechanical stress. The accumulation of stress strongly depends on environmental conditions such as flat ground or uphill/downhill, and accumulates in knee compartments; only a few studies have reported the effects of different environments on lateral and medial meniscus extrusion. This study aimed to investigate the effects of cumulative uphill/downhill stress on the meniscal extrusion in each compartment.

Methods

A total of 30 healthy volunteers with 30 affected knees were involved in this cohort study (mean age, 22.0 ± 1.1 years; men, n = 14). The participants were divided into flat-walking, uphill/downhill-walking, and uphill/downhill-jogging groups and their numbers of steps taken were recorded during the effort. Moreover, medial and lateral meniscal extrusions during walking were evaluated using ultrasound three times, before and after efforts (T1) and (T2), and one day after efforts (T3), respectively.

Results

In the flat-walking group, no significant differences were observed between the follow-up periods. Conversely, in the uphill/downhill-walking and jogging groups, the medial meniscus extrusion at T2 was significantly higher than that at T1. Conversely, the medial meniscus extrusion at T3 was significantly lower than that at T2. By contrast, the lateral meniscus did not show any difference between the follow-up periods in any group.

Conclusion

Temporary extrusion of the meniscus occurred after uphill/downhill tasks in healthy volunteers, and its reaction was observed only in the medial meniscus.

Functional electrostimulation therapy for vastus medialis decreases the varus thrust during gait

[Purpose] This study aimed to investigate whether modification of vastus medialis activity can delay the varus thrust. [Participants and Methods] Ten participants (Kellgren-Laurence grades I: n=2, II: n=6, and III: n=2) diagnosed with knee osteoarthritis were enrolled. The intervention involved free walking on a 10-m walkway at any speed after donning a functional electrical stimulation set to contract the vastus medialis before heel contact. Using a Vicon Nexus ground reaction force meter and a wireless electromyograph DELSYS, varus thrust, maximal knee extension angle, maximal knee adduction moment, and vastus medialis onset time were assessed both before and after intervention. [Results] A significant difference in varus thrust was detected from before to after the intervention (2.7 ± 1.1° vs. 2.2 ± 1.3°). Both the vastus medialis activation time (-0.06 ± 0.09 vs. -0.21 ± 0.1) and the knee-joint extension angle (8.7 ± 5.1° vs. 5.5 ± 5.9°) decreased following intervention, whereas the knee adduction moment significantly increased (0.50 ± 0.20° vs 0.56 ± 0.18°). [Conclusion] Wearing the functional electrical stimulation set caused the vastus medialis to act earlier in response to heel strike, thereby improving the knee-joint extension angle and suppressing varus thrust.

Association between three-dimensional motion analysis of the thumb and clinical parameters in patients with carpal tunnel syndrome

We analysed the relationship between motor dysfunction of the thumb and the clinical parameters of carpal tunnel syndrome using three-dimensional motion analysis. This single-centred, prospective study included 65 hands in 51 patients with idiopathic carpal tunnel syndrome and 30 healthy hands. Three-dimensional thumb kinematics were acquired using a motion capture system with a retroreflective surface-based marker method. The trajectory area of thumb tip, adduction and abduction of the trapeziometacarpal joints and metacarpophalangeal joints were correlated with the clinical parameters. There was no significant correlation between the results of motion analysis values and patient-reported outcomes measures. Thumb movement disorder associated with carpal tunnel syndrome affected specific activities of daily living based on the pinching movements, such as 'writing' and 'buttoning clothes' among the patient-reported outcome measure items.Level of evidence: III.

Combined over-the-top reconstruction with posterolateral bundle remnant re-tensioning in pediatric anterior cruciate ligament reconstruction: A technical note

Epiphyseal injury, particular on femoral side, is a major concern in pediatric anterior cruciate ligament (ACL) reconstruction. Therefore, the over-the-top route (OTTR) method has frequently been selected in pediatric ACL reconstruction, with good clinical results reported. However, a cadaver study reported the inferior rotational stability of the OTTR method to that of anatomical single bundle reconstruction. In recent years, a new method of reconstruction, which involves the remnant being detached, re-tensioned, and re-attached, achieved good short-term results. We developed a surgical method to restore the remnant to the posterolateral (PL) bundle footprint and obtain rotational stability in patients, thereby preserving the remnant. We hypothesized that repairing the residual remnant to the PL bundle footprint in pediatric ACL reconstruction could achieve rotational stability. This report offers the surgical techniques for PL bundle tensioning repair using remnants in the pediatric ACL OTTR procedure.

Nonunion of Isolated Medial Cuneiform Fracture Fixed With a Compression Screw and Compression Staple: A Case Report

Isolated cuneiform fractures are rare and account for only 1.7% of all midfoot fractures. Medial cuneiform fractures can be treated conservatively or surgically, with good clinical outcomes. However, nonunion is a rare complication of medial cuneiform fractures, and only a few cases have been reported in the literature. We report a case of a medial cuneiform fracture requiring surgical treatment that had a good clinical outcome. A 15-year-old boy presented to an orthopedic clinic with a complaint of pain in his right foot. The patient had landed on the foot during a handball game and was treated conservatively for several months. However, his symptoms persisted, and he was referred to our clinic for further evaluation, where he was diagnosed with medial cuneiform nonunion of the right foot. Open reduction and internal fixation surgery using a compression screw and staple and autologous bone grafting were performed. Postoperatively, bone union was observed, and the patient returned to full competition with no complaints of pain during exercise. The Self-Administered Foot Evaluation Questionnaire (SAFE-Q) score at 21 months after surgery was 100.0 for the following subscales: Pain & Pain-Related; Physical Functioning & Daily Living; Social Functioning; Shoe-Related; General Health & Well-Being; and Sport (handball). We encountered a case of an isolated medial cuneiform fracture that required surgical treatment. During the surgical treatment, fixation with a combination of compression staples and screws may be considered simple and useful for achieving strong fixation because the medial cuneiform fracture has a small bone fragment.

First tarsometatarsal joint mobility in hallux valgus during gait: A synchronized ultrasound and three-dimensional motion capture analysis

PURPOSE

To quantify the vertical translation between the first metatarsal and medial cuneiform during the stance phase of gait in young individuals with and without hallux valgus.

DESIGN

This cross-sectional observational study included 34 young adults (male, n = 4; female, n = 30) who were divided into three groups according to the hallux valgus angle: control (< 20°, n = 13), mild hallux valgus (≥ 20° to < 30°, n = 12), and moderate hallux valgus (≥ 30°, n = 9). The mobility of the first tarsometatarsal joint was evaluated during the stance phase using B-mode ultrasound synchronized with a motion analysis system.

RESULTS

The medial cuneiform shifted more plantar during the early phase in mild hallux valgus and during the middle and terminal phases in moderate hallux valgus than in control. The severity of the hallux valgus was correlated with a trend toward plantar shift of the medial cuneiform. The first metatarsal was located more dorsal than the medial cuneiform; however, there was no significant variation. No significant differences in the peak ankle plantarflexion angle and moment were noted between the groups.

CONCLUSION

The hypermobility of the first tarsometatarsal joint, especially plantar displacement of the medial cuneiform in the sagittal plane, was found in young individuals with hallux valgus during the stance phase of gait, and the mobility increased with the severity of hallux valgus. Our findings suggest the significance of preventing hallux valgus deformity early in life.

Effect of lateral wedge length on knee adduction moment reduction mechanics during gait

Lateral wedge insole (LWI) wear is a well-known conservative treatment for patients with knee osteoarthritis and is expected to decrease knee joint loading. Although the effect of LWI length on knee adduction moment (KAM) has been investigated, the biomechanical mechanism has not been fully investigated. Twelve healthy young subjects walked in the laboratory with and without 2 different lengths of LWIs. Three-dimensional motion analysis was performed to calculate the first and second peaks and impulses of the KAM during the stance phase. In addition, the knee-ground reaction force lever arm (KLA) and center of pressure (COP), ankle eversion moment, and ankle eversion angle were calculated. The first peak of KAM was lower, COP was displaced outward, and KLA was shorter with both LWIs attached. On the other hand, the second peak of KAM was lower with longer LWIs, COP was displaced outward, and KLA was shorter. The KAM impulse was significantly smaller in the condition with longer LWI than in the other conditions with smaller ankle eversion motion; longer LWI induced COP to the lateral side through the stance phase and kept KLA short, thus reducing the KAM impulse.

Myelin-Specific microRNA-23a/b Cluster Deletion Inhibits Myelination in the Central Nervous System during Postnatal Growth and Aging

Microribonucleic acids (miRNAs) comprising miR-23a/b clusters, specifically miR-23a and miR-27a, are recognized for their divergent roles in myelination within the central nervous system. However, cluster-specific miRNA functions remain controversial as miRNAs within the same cluster have been suggested to function complementarily. This study aims to clarify the role of miR-23a/b clusters in myelination using mice with a miR-23a/b cluster deletion (KO mice), specifically in myelin expressing proteolipid protein (PLP). Inducible conditional KO mice were generated by crossing miR-23a/b clusterflox/flox mice with PlpCre-ERT2 mice; the offspring were injected with tamoxifen at 10 days or 10 weeks of age to induce a myelin-specific miR-23a/b cluster deletion. Evaluation was performed at 10 weeks or 12 months of age and compared with control mice that were not treated with tamoxifen. KO mice exhibit impaired motor function and hypoplastic myelin sheaths in the brain and spinal cord at 10 weeks and 12 months of age. Simultaneously, significant decreases in myelin basic protein (MBP) and PLP expression occur in KO mice. The percentages of oligodendrocyte precursors and mature oligodendrocytes are consistent between the KO and control mice. However, the proportion of oligodendrocytes expressing MBP is significantly lower in KO mice. Moreover, changes in protein expression occur in KO mice, with increased leucine zipper-like transcriptional regulator 1 expression, decreased R-RAS expression, and decreased phosphorylation of extracellular signal-regulated kinases. These findings highlight the significant influence of miR-23a/b clusters on myelination during postnatal growth and aging.

Effect of a compression staple on correction of varus deformity during arthroscopic ankle arthrodesis

BACKGROUND

Arthroscopic ankle arthrodesis (AAA) has become popular because of its higher rate of bone union, lower invasiveness, and shorter hospital stays compared to those of open arthrodesis. However, postoperative malalignment is often observed for severe varus deformity, which can cause nonunion, pain, and adjacent joint arthrosis. A compression staple can provide a persistent, strong compressive force on the bone surface. This study aimed to clarify the difference in alignment correction in AAA by comparing a compression staple and screws fixation with screws-only fixation pre- and postoperatively.

METHODS

Seventy ankles in 67 patients undergoing AAA were retrospectively reviewed. AAA with three screws through the distal tibia was performed in 53 ankles, and 17 ankles underwent AAA with a compression staple and two screws. After the preparation of the joint surface arthroscopically, patients in the S group had three canulated cancellous screws inserted through the medial tibia. Patients in the CS group had a compression staple placed at the lateral aspect of the tibiotalar joint and two screws inserted through the medial side. Clinical scores and pre-and postoperative alignment on plain radiographs were compared between the two procedures.

RESULTS

There were no significant differences in the pre-and postoperative Japanese Society for Surgery of the Foot scale. One ankle in the S group exhibited nonunion. There were no significant differences in talar tilt and tibiotalar angles between the groups. The tibial plafond angle in the CS group was significantly lower than that in the S group (p < 0.05). Postoperatively, talar tilt and tibiotalar angles on the coronal image, and the lateral tibiotalar angle in the CS group were significantly lower than those in the S group (p < 0.05).

CONCLUSION

AAA with a compression staple and two-screw fixations could obtain more optimal alignments than AAA with screw-only fixation, even in cases with severe varus deformity.

Evaluation of Epiconus and Conus Medullaris Disorders due to Thoracolumbar Vertebral Fracture using Motor Evoked Potentials

STUDY DESIGN

A retrospective case-control study.

OBJECTIVE

To characterize the motor evoked potential (MEP) when the epiconus or conus medullaris is compressed by a fracture of the T12 or L1 vertebra.

SUMMARY OF BACKGROUND DATA

Although the characteristics of compressive cervical and thoracic myelopathy with transcranial magnetic stimulation MEP have been reported, the MEP parameters in compressive disorders of the epiconus and conus medullaris have not yet been characterized.

METHODS

Twenty patients with T12 or L1 vertebral fractures who had lower extremity symptoms due to compression of the epiconus or conus medullaris were included. These patients were compared with 28 healthy controls and 32 patients with cervical spondylotic radiculopathy (CSR) without spinal cord compression. MEPs of abductor hallucis muscles were recorded using transcranial magnetic stimulation and electrical stimulation of the tibial nerve. MEP latency, central motor conduction time (CMCT), and peripheral conduction time (PCT) were evaluated.

RESULTS

MEP latency, CMCT, and PCT were significantly longer in patients with fractures than in healthy controls and patients with CSR. MEP latency was most accurate for differentiating patients with fracture from healthy controls (cutoff value, 40.0 ms, sensitivity, 95.0%; specificity, 100%), and CMCT was most accurate for comparing patients with fracture and CSR (cutoff value, 15.5 ms, sensitivity, 80.0%; specificity, 93.8%). In the distinction between patients with fracture and CSR, 16 of the 20 patients with fracture exceeded the cutoff values for any of the parameters, and 12 of them exceeded the cutoff values for all parameters. There was no significant correlation between the linear distance from the most inferior end of the spinal cord to the site of compression and any of the MEP parameters.

CONCLUSION

Both CMCT and PCT are often prolonged in compressive lesions of the epiconus and conus medullaris, and MEP latency and CMCT are useful in the diagnosis.

Development of a novel animal model of lumbar vertebral endplate lesion by intervertebral disk injection of monosodium iodoacetate in rats

PURPOSE

Vertebral endplate lesions (EPLs) caused by severe disk degeneration are associated with low back pain. However, its pathophysiology remains unclear. In this study, we aimed to develop a vertebral EPL rat model mimicking severe intervertebral disk (IVD) degeneration by injecting monosodium iodoacetate (MIA) into the IVDs and evaluating it by assessing pain-related behavior, micro-computed tomography (CT) findings, and histological changes.

METHODS

MIA was injected into the L4-5 and L5-6 IVDs of Sprague-Dawley rats. Their behavior was examined by measuring the total distance traveled and the total number of rearing in an open square arena. Bone alterations and volume around the vertebral endplate were assessed using micro-CT. Safranin-O staining, immunohistochemistry, and tartrate-resistant acid phosphatase (TRAP) staining were performed for histological assessment.

RESULTS

The total distance and number of rearing times in the open field were significantly reduced in a time-dependent manner. Micro-CT revealed intervertebral osteophytes and irregularities in the endplates at 12 weeks. The bone volume/tissue volume (BV/TV) around the endplates significantly increased from 6 weeks onward. Safranin-O staining revealed severe degeneration of IVDs and endplate disorders in a dose- and time-dependent manner. Calcitonin gene-related peptide-positive nerve fibers significantly increased from 6 weeks onward. However, the number of osteoclasts decreased over time.

CONCLUSION

Our rat EPL model showed progressive morphological vertebral endplate changes in a time- and concentration-dependent manner, similar to the degenerative changes in human IVDs. This model can be used as an animal model of severe IVD degeneration to better understand the pathophysiology of EPL.

Short-segment spinal fusion for chronic low back pain with bone marrow edema adjacent to the vertebral endplate in adult spinal deformity

PURPOSE

Corrective long spinal fusion is a widely accepted surgical method for patients with adult spinal deformities. However, instrumented long fusion is associated with a significant risk of complications. Therefore, we aimed to assess the success of short-segment spinal fusion, particularly for bone marrow edema (BME) adjacent to the vertebral endplate, in patients with low back pain (LBP) and spinal deformity.

METHODS

A prospective study was performed at multiple hospitals wherein we monitored patients with spinal deformities and accompanying LBP. Patients aged ≥ 50 years with a minimum LBP severity score of 40 mm on the visual analog scale (VAS) were included in the study. We also included patients with lumbar BME on magnetic resonance imaging. Short spinal fusion was performed on segments with BME. Clinical evaluations of LBP on VAS and Oswestry Disability Index (ODI), and radiological parameters for sagittal vertical axis (SVA), pelvic incidence (PI), lumbar lordosis (LL) and pelvic tilt (PT) were carried out.

RESULTS

Overall, 35 patients (22 men and 13 women), with a mean age of 66.7 years and a mean follow-up period of 32 months, were included in the study. The mean VAS and ODI scores were 72.4 mm and 49.0% before surgery and 25.5 mm and 29.9% at the final follow-up, respectively; these parameters significantly improved after surgery. The SVA, PI-LL, and PT scores were 70.1 mm, 20.9°, and 22.8° before surgery and 85.4 mm, 13.8°, and 22.7° at the final follow-up, respectively. The spinal alignment parameters did not change significantly after surgery.

CONCLUSIONS

Short-segment spinal fusion is effective for treating LBP and spinal deformity with BME adjacent to the vertebral endplate without spinal correction.

Factors affecting stress shielding and osteolysis after reverse shoulder arthroplasty: A multicenter study in a Japanese population

BACKGROUND

Stress shielding and osteolysis around the humeral stem after reverse shoulder arthroplasty causes loosening and periprosthetic fractures and reduces bone stock during revision surgery. In Japanese patients, who have relatively small bodies, different characteristics may exist regarding the occurrence of these changes compared with the characteristics of Westerners, who have relatively larger frames. The purpose of this multicenter study was to investigate the incidence and clarify the predictors of stress shielding and osteolysis in Japanese individuals who underwent reverse shoulder arthroplasty.

METHODS

The occurrence of stress shielding and osteolysis was investigated in 135 shoulders that had undergone reverse shoulder arthroplasty at least 2 years prior in five Japanese hospitals. During post-surgical follow-up, which was conducted every 3 months, the locations of the stress shielding occurrences, such as cortical thinning and osteopenia (which primarily occurred in zones 1, 2, and 7, where 1 is the greater tuberosity and 7 is the calcar part), spot weld, and condensation lines, were recorded. Cases without any abnormal findings on radiographs obtained up to ≥2 years after surgery were regarded as having no abnormalities. Finally, the predictors of cortical thinning and proximal humeral osteolysis were assessed using univariate and multivariate regression analyses.

RESULTS

Cortical thinning and osteopenia occurred in 68 shoulders, a condensation line occurred in 37 shoulders, and spot weld occurred in 23 shoulders. In particular, greater tuberosity and calcar osteolysis occurred in 40 and 47 shoulders, respectively. Long stem, cementless stem, and a larger proximal filling ratio were independent predictors of cortical thinning and osteopenia, whereas a cementless stem, larger metaphysis diameter, and a larger proximal filling ratio were associated with proximal humeral osteolysis.

CONCLUSIONS

The predictors of stress shielding and osteolysis included the use of long stems, cementless stems, larger proximal filling ratios, and larger metaphysis diameters.

LEVEL OF EVIDENCE

retrospective comparative study (Level III).

Temporal validation of a clinical prediction rule for distinguishing locomotive syndromes in community-dwelling older adults: A cross-sectional study from the DETECt-L study

Objectives

Clinical prediction rules are used to discriminate patients with locomotive syndrome and may enable early detection. This study aimed to validate the clinical predictive rules for locomotive syndrome in community-dwelling older adults.

Methods

We assessed the clinical prediction rules for locomotive syndrome in a cross-sectional setting. The age, sex, and body mass index of participants were recorded. Five physical function tests-grip strength, single-leg standing time, timed up-and-go test, and preferred and maximum walking speeds-were measured as predictive factors. Three previously developed clinical prediction models for determining the severity of locomotive syndrome were assessed using a decision tree analysis. To assess validity, the sensitivity, specificity, likelihood ratio, and post-test probability of the clinical prediction rules were calculated using receiver operating characteristic curve analysis for each model.

Results

Overall, 280 older adults were included (240 women; mean age, 74.8 ± 5.2 years), and 232 (82.9%), 68 (24.3%), and 28 (10.0%) participants had locomotive syndrome stages ≥ 1, ≥ 2, and = 3, respectively. The areas under the receiver operating characteristics curves were 0.701, 0.709, and 0.603, in models 1, 2, and 3, respectively. The accuracies of models 1 and 2 were moderate.

Conclusions

These findings indicate that the models are reliable for community-dwelling older adults.

Comparison of Clinical Outcomes With Arthroscopic ATFL Repair With the CFL Repair and Open ATFL and CFL Repair in Chronic Lateral Ankle Instability

It is important to eliminate instability related to chronic lateral ankle instability (CLAI) to prevent osteoarthritis progression. We performed arthroscopic anterior talofibular ligament (ATFL) repair and performed calcaneofibular ligament (CFL) repair if instability remained. This study aimed to assess the clinical outcomes of our arthroscopic procedure compared to that of open surgery. Forty ankles underwent arthroscopic surgery and 23 ankles underwent open surgery to repair the lateral ankle ligaments for CLAI. In the arthroscopic surgery, varus stress was applied under fluoroscopy after ATFL repair, and CFL repair was performed if instability remained. Open surgery was performed using the Broström procedure with ATFL and CFL repair. To assess clinical outcomes, American Orthopaedic Foot & Ankle Society (AOFAS) and Karlsson-Peterson (KP) scores were collected preoperatively and at the final follow-up. The talar tilt angle (TTA) was measured preoperatively and 1 year postoperatively. The arthroscopic group showed significantly higher AOFAS and KP scores at the final follow-up compared to the open surgery group. There was no significant difference in TTA at 1 year between the groups. In open surgery, 2 patients required revision surgery. There were no major complications, but scar-related pain in 2 cases of open surgery was reported. Arthroscopic ATFL repair with the CFL repair gave satisfactory clinical outcomes compared to open surgery in CLAI because of low invasive to soft tissue including the joint capsule. It is important to minimize soft tissue dissection in repairing the lateral ankle ligament in patients with CLAI.

Myopericytoma of the patella with local recurrence and patellectomy: A case report

INTRODUCTION AND IMPORTANCE

Myopericytomas are tumors originating from perivascular myoid cells and exhibiting a wide range of histologic growth patterns. They rarely occur in bones, and no case of myopericytoma in the patella has been reported so far.

CASE PRESENTATION

A 74-year-old male presented with a chief complaint of pain in the left knee. Magnetic resonance imaging revealed bone tumor and osteolytic lesions of the patella. The patient underwent bone tumor curettage and filling of the cavity with artificial bone. However, as the tumor reoccurred, a patellectomy was performed. The patient regained premorbid functional status after surgery. Additionally, there was no radiological evidence of recurrence of the lesion 3 years after patellectomy.

CLINICAL DISCUSSION

Myopericytoma of the patella is very rare. However, it should be considered for the differential diagnosis of lytic lesions of the bone. Although surgery is curative, patellectomy may be necessary for recurrent cases.

CONCLUSION

In conclusion, we report the first case of patellar myopericytoma. Although patellar myopericytoma might be rare, it should be considered for the differential diagnosis of lytic lesions of the bone. Surgery is curative; however, patellectomy may be necessary in recurrent cases.

Arthroscopic Fixation Using Bioabsorbable Pins With Bone Grafting via a Medial Malleolus Approach to Treat Osteochondral Lesion of the Talus

Fixation of the osteochondral fragment has the advantage to restore the naturally congruent morphology of the talar dome with native hyaline cartilage in the treatment of the osteochondral lesion of the talus (OLT). Surgical treatment of medial talar osteochondral lesions is commonly done through a medial malleolar osteotomy. However, a medial malleolar osteotomy is an invasive procedure and gives negative impacts on clinical outcomes. Fixation for the posteromedial lesion of the OLT without the medial malleolar osteotomy may provide good clinical outcomes. We showed arthroscopic fixation for medial OLT without the medial malleolar osteotomy. Curettage and bone grafting between the fragment and its bed were performed, and then 2-mm bone tunnel in the medial malleolus was created. Bioabsorbable pins were inserted through the tunnel to fix the osteochondral fragment. Three cases (mean age 18.6 years) were treated using this technique for medial OLT and followed at 16 months (range, 12-24 months). The Japanese Society for Surgery of the Foot scale improved from 73.3 ± 1.2 points before surgery to 95.7 ± 7.5 points at the final follow-up. Bone union of the osteochondral fragment was confirmed on magnetic resonance imaging (MRI). Arthroscopic fixation for medial OLT is less invasive and yields good clinical outcomes.Levels of Evidence: Level V.

Relationship between pain and intra-articular pathology in patients with chronic lateral ankle instability

PURPOSE

Repeated ankle sprains can lead to chronic lateral ankle instability (CLAI). It is unclear whether CLAI causes pain unless complicated by intra-articular lesions. This study aimed to analyze the characteristics of pain and the relationship between pain and intra-articular pathology in patients with CLAI.

MATERIALS AND METHODS

Fifty-three ankles in 46 patients with CLAI who had undergone surgery were retrospectively reviewed. The self-administered foot evaluation questionnaire (SAFE-Q) was given to patients the day before surgery. Intra-articular lesions were assessed using arthroscopy and magnetic resonance imaging (MRI). In addition, the Hounsfield Unit (HU) on computed tomography (CT) of the medial gutter was measured. The relationship between pain and intra-articular findings was also analyzed.

RESULTS

The pain and pain-related scores in the SAFE-Q were significantly correlated with synovitis in 96.3% (rs = - 0.532). HU ratios in the tibia and talus were also significantly correlated with pain (rs = - 0.603, - 0.534, respectively). The arthroscopic synovitis score and HU ratios in patients with high pain scores were significantly higher than those in patients with low pain scores. Forty ankles (75.5%) had synovitis and articular cartilage injuries were observed in 22 ankles (41.5%). Patients with fluid collection or bone marrow lesions (BML) scored significantly lower in pain than those without, but there was no significant difference between patients with and without cartilage injury. Multiple regression analysis revealed that a high synovitis score and HU ratio of the talus were significantly associated with high pain.

CONCLUSIONS

Intra-articular lesions such as synovitis and BML were associated with pain in patients with CLAI. Osteosclerotic changes in the medial gutter also induced ankle pain, indicating that osteoarthritic changes had already begun. Therefore, lateral ankle ligament injuries after ankle sprain should be appropriately treated to avoid secondary degenerative changes.

LEVEL OF EVIDENCE: 4

On-Top Osteotomy of the Phalanx Base Combined With Modified Bilhaut: Cloquet Procedure for Atypical Radial Polydactyly

In this report, we present the combination of on-top plasty with a modified Bilhaut-Cloquet procedure for treating atypical radial polydactyly with duplication at the metacarpophalangeal (MP) joint and triphalangism of the radial and ulnar phalanges, hypoplastic middle phalanx of the radial thumb, and hypoplastic phalanx base of the ulnar thumb. To preserve the stable MP and interphalangeal joints of the radial and ulnar thumbs, respectively, on-top plasty involved osteotomizing the middle phalanx and transferring the distal end of the middle phalanx of the ulnar finger to the phalanx base of the radial thumb. A modified Bilhaut-Cloquet procedure was used to combine the tips and nails of both thumbs. Twelve months postoperatively, good joint alignment and thumb tip appearance were achieved. On-top plasties effectively combined the desirable parts of both thumbs. The modified Bilhaut-Cloquet technique is particularly well-suited for atypical cases, such as the present case.

A Novel Surgical Technique Using a Hockey Stick-Like Guided Knife to Go Through the Eyes of a Needle for Trigger Finger

Trigger finger surgery is primarily managed with open surgery accompanied by 10-14 days of postoperative recovery, which may interrupt activities of daily living. In the past, we attempted to perform percutaneous surgery by inserting a hockey stick-shaped guide knife through a scalpel incision several millimeters long. Sometimes, we encounter difficult cases wherein triggering does not disappear despite repeated attempts to release the A1 pulley through the small incision, thus forcing us to extend the incision. As a result, the postoperative recovery is sometimes prolonged. We describe our experience using a novel percutaneous procedure in which a guide knife was inserted through one or two 20-gauge needle holes, instead of a scalpel skin incision, to release the A1 pulley. We describe a new method that minimizes skin and soft tissue damage and reliably shortens posttreatment recovery.

High incidence of osteoarthritic changes in patients with osteochondral lesions of the talus without chronic lateral ankle instability

BACKGROUND

It is unclear whether osteochondral lesions of the talus (OLTs) without chronic lateral ankle instability (CLAI) progress to osteoarthritis, which affects the therapeutic strategy. Especially, the efficacy of conservative treatment for OLT remains controversial. Since various anatomical abnormalities have been reported, there may be abnormal movement of the talus in the mortise, causing ankle instability. We hypothesized that OLTs have frequent osteoarthritic changes even without CLAI. This study aimed to evaluate the incidence of osteoarthritic changes and stress distribution on the talus in OLT.

METHODS

Fifty-eight ankles with medial OLT without CLAI were retrospectively reviewed. Osteophytes and joint space narrowing on radiographs were scored using Kraus's classification and compared to ankles without OLTs. OA scores were compared between over 18 years and less than 17 years in OLTs. On computed tomography images, the area of OLTs was measured. Besides, Hounsfield Units (HU) of the talus in patients with and without OLTs were measured and compared.

RESULTS

Osteoarthritic changes were observed in 54 of the 58 ankles (94.8%) in the OLT patients. Osteophytes were frequently observed at the medial gutter and anterior tibial plafond. The OA score in patients aged over 18 years was significantly higher than that in patients aged less than 17 years (P < 0.05). HU values in the talus were significantly higher than those in non-OLT patients. OLTs more than 100 mm2 had a significantly higher osteoarthritic score than those less than 100 mm2.

CONCLUSION

Medial OLT without CLAI has frequently osteoarthritic changes, especially large lesions. Osteoarthritic changes in OLTs will progress over time, which needs to be considered when deciding whether to perform the surgical or non-surgical treatment.

Loosening of the anterolateral capsule affects the stability after arthroscopic lateral ankle ligament repair of chronic ankle instability

PURPOSE

Arthroscopic anterior talofibular ligament (ATFL) repair for chronic lateral ankle instability (CLAI) has been widely performed. The recurrence of the instability after the surgery sometimes occurs, which may cause the development of osteoarthritis. Therefore, it is important to elucidate the factors of the recurrence. This study aimed to evaluate the loosening of the capsule in the MRI and whether it affected clinical outcomes or not in arthroscopic ATFL repair.

MATERIALS AND METHODS

Thirty-eight ankles in 35 patients with CLAI treated by arthroscopic lateral ligament repair were included. The capsule protrusion area defined as the area that protruded ATFL laterally from the line connecting the fibula and talus attachment on MRI was measured. Capsule protrusion area in ankles with or without CLAI was compared and the relationships between it and clinical outcomes were assessed.

RESULTS

The capsule protrusion area in the CLAI group (74.2 ± 36.4 mm2) was significantly larger than that in the control (25.5 ± 14.3 mm2) (p < 0.01). The capsule protrusion area in the poor remnant group (93.8 ± 36.4 mm2) was significantly larger than that in the excellent (53.2 ± 40.3 mm2) (p < 0.05). The capsule protrusion area in the patients with recurrent instability (99.8 ± 35.2 mm2) was significantly larger than that without recurrent instability (62.4 ± 30.9 mm2) (p < 0.01). Clinical scores in the recurrent group were significantly lower than those in the non-recurrent group (p < 0.05).

CONCLUSIONS

Capsule loosening would be one of the causes of the recurrence of instability after arthroscopic lateral ankle ligament repair. Evaluation of the capsule protrusion area on MRI is helpful to choose appropriate surgical procedures for CLAI patients.

LEVEL OF EVIDENCE: 4

Synergistic VSV Virotherapy and Carbon Nanotube Photothermal Therapy for Osteosarcoma in Murine Models

BACKGROUND/AIM

Wide resection is usually performed for malignant bone and soft tissue tumors, but there is often functional impairment of the affected limb. In this study, we performed virotherapy with the vesicular stomatitis virus (VSV) and photothermal therapy using carbon nanotubes (CNTs) in combination for osteosarcoma, followed by marginal excision. The possibility of local treatment of the primary tumor was then assessed.

MATERIALS AND METHODS

LM-8 cells (1×107) were subcutaneously implanted into 5-week-old mice to generate an in vivo osteosarcoma mouse model. Marginectomy was performed. Four groups with six mice each were created: VSV+SWCNTs group, VSV group, SWCNTs group, and an untreated group. Tumor margin resection was performed 2 weeks after tumor cell transplantation. The primary tumor volume, local recurrence, distant metastasis, and survival rate were evaluated.

RESULTS

The combination of VSV virotherapy and CNTs photothermal therapy resulted in shrinkage of the primary tumor and reduced local recurrence after marginectomy. There was no significant difference in distant metastasis or survival rate for all groups.

CONCLUSION

Combining virotherapy with VSV and CNTs photothermal therapy is useful for local treatment of osteosarcoma in murine models, possibly allowing for smaller tumor resection margins.

Relationship between foot morphologic characteristic and postural control after jump-landing in youth competitive athletes

BACKGROUND

Foot arch dynamics play an important role in dynamic postural control. Association between foot arch dynamics and postural control among adolescent athletes remains poorly explored.

OBJECTIVE

To examine the relationship between foot arch dynamics, intrinsic foot muscle (IFM) morphology, and toe flexor strength and dynamic postural stability after jump landing and repetitive rebound jump performance in competitive adolescent athletes.

METHODS

Based on foot arch dynamics, evaluated from relative change in the foot arch height in sitting and standing positions, 50 adolescent athletes were classified as stiff, normal, or flexible. IFM morphology was evaluated by ultrasonography. Dynamic postural stability index (DPSI) was measured as participants jumped and landed with the right leg onto a force plate, whereas repetitive rebound jumping performance was assessed using the jump height and reactive jump index.

RESULTS

The stiff group had a significantly worse DPSI and vertical stability index than the normal group (p= 0.26, p= 0.44, respectively), and worse anteroposterior stability index (APSI) values than the flexible group (p= 0.005). Multivariate regression models of the relationship between the APSI and foot arch dynamics showed adequate power (probability of error = 0.912).

CONCLUSIONS

Increased foot arch stiffness negatively affects dynamic balance during jump-landing, which may deteriorate their performance.

Long-term conservative treatment outcomes for midshaft clavicle fractures: a 10-to-30-year follow-up

BACKGROUND

Few reports exist on the long-term outcomes of midshaft clavicle fracture conservative treatments. Therefore, this study investigated the long-term outcome of this treatment in patients with midshaft clavicle fractures.

METHODS

Patients were treated conservatively for midshaft clavicle fractures with a figure-of-eight bandage between 10 and 30 years ago. Subsequently, a telephone survey was used to follow-up these patients, and 38 were successfully evaluated. The mean term after trauma was 17.0 years. Afterward, the American Shoulder and Elbow Surgeons Shoulder (ASES) score and Shoulder pain and disability index (SPADI) on the affected and unaffected sides were calculated based on the filled questionnaires. We defined patients whose ASES and SPADI on the affected side were worse than the unaffected side as the symptomatic group. Furthermore, plain radiographs measured proportional changes in clavicular length and displacement.

RESULTS

The ASES scores of the affected side were significantly lower than those of the unaffected side, and the SPADI of the affected side was significantly higher than that of the unaffected side. Furthermore, the symptomatic group's proportional changes in clavicular length and displacement were significantly larger than the asymptomatic group.

CONCLUSION

The affected shoulder side was more symptomatic than the unaffected side 10 to 30 years after the trauma when midshaft clavicle fractures were treated conservatively. Moreover, several patients became symptomatic for fractures with a larger proportional change in clavicular length or displacement.

Oxidation-treated carbon nanotube yarns accelerate neurite outgrowth and induce axonal regeneration in peripheral nerve defect

Carbon nanotubes (CNTs) have the potential to promote peripheral nerve regeneration, although with limited capacity and foreign body reaction. This study investigated whether CNTs hydrophilized by oxidation can improve peripheral nerve regeneration and reduce foreign body reactions and inflammation. Three different artificial nerve conduit models were created using CNTs treated with ozone (O group), strong acid (SA group), and untreated (P group). They were implanted into a rat sciatic nerve defect model and evaluated after 8 and 16 weeks. At 16 weeks, the SA group showed significant recovery in functional and electrophysiological evaluations compared with the others. At 8 weeks, histological examination revealed a significant increase in the density of regenerated neurofilament and decreased foreign body giant cells in the SA group compared with the others. Oxidation-treated CNTs improved biocompatibility, induced nerve regeneration, and inhibited foreign-body reactions.

Decreased Joint Position Sense of the Ankle Joint Is a Risk Factor for Falls in the Elderly

BACKGROUND

Falls in the elderly are common causes of morbidity, mortality, loss of independence, and poor quality of life. We hypothesized that decreased ankle position sense is one among several risk factors that might lead to falls.

METHODS

A total of 54 feet from 28 patients over 65 years of age and 10 feet from five healthy volunteers were included. Measurements of ankle position sense, medical history, and fall history within a year were obtained, which were compared between the groups.

RESULTS

The mean replication error angle of internal and external rotation was significantly higher in the elderly, and the mean replication error angle of internal rotation was significantly higher in the group with a history of falls.

CONCLUSION

The mean replication error angle of internal rotation and a history of fractures were significant risk factors for falls. Hence, an increase in the mean replication error angle of internal rotation may increase the risk of falls in the elderly population.

Balancing ability of patients with lumbar spinal canal stenosis

PURPOSE

To determine the relationship between postural sway and the severity of lumbar spinal canal stenosis as well as the effect on postoperative improvement.

METHODS

Stabilometry was performed before and 6 months after surgery in 52 patients (29 men and 23 women; mean age, 74.1 ± 7.8 years) who underwent decompression surgery for lumbar spinal canal stenosis. The environmental area (EA; the area surrounding the circumference of the stabilogram) and locus length per EA (L/EA) were evaluated. The patients were divided into moderate (n = 22) and severe (n = 30) groups according to the severity of canal stenosis. Patient characteristics and parameters were compared between the groups before and after surgery, including the visual analog scale (VAS) score for leg pain, Oswestry Disability Index (ODI), EA, and L/EA. In addition, factors affecting EA and L/EA were evaluated using multiple regression analysis.

RESULTS

Age (p = 0.031), preoperative EA (p < 0.001), preoperative L/EA (p = 0.032), and sagittal vertical axis (p = 0.033) were significantly different between groups. The VAS score and ODI significantly improved postoperatively in both groups (p < 0.001). The EA significantly improved postoperatively only in the severe group (p < 0.001), whereas the L/EA did not significantly improve in either group. Multiple regression analysis showed that only the severity of canal stenosis was significantly associated with preoperative EA (p = 0.030), whereas age (p = 0.040) and severity of canal stenosis (p = 0.030) were significantly associated with preoperative L/EA. Diabetes was significantly associated with postoperative EA (p = 0.046) and L/EA (p = 0.030).

CONCLUSION

The severity of canal stenosis affected abnormal postural sway, which improved after decompression surgery.

Range of Motion and Muscle Strength Changes in Japanese Professional Pitchers During the Baseball Season

BACKGROUND

There are no studies examining changes in the physical function throughout the baseball season in Japanese professional players. We examined the range of motion (ROM) and muscle strength changes in professional baseball pitchers as the season progresses.

MATERIALS AND METHODS

Five professional baseball pitchers were included. ROM, flexibility, and muscle strength of the trunk and shoulder, elbow, hip, knee, and ankle joints were measured pre-season (PRE), mid-season (MID), and post-season (POST).

RESULTS

The total shoulder arc ROM of the dominant sides significantly decreased compared to that of the nondominant sides at MID and POST. Shoulder abduction muscle strength of the dominant sides significantly decreased at POST compared to that at PRE. In the trunk, lateral flexion ROM of bilateral sides significantly decreased at MID and POST compared to that at PRE, and the duration time of the side bridge test of the dominant sides significantly decreased at POST to that at PRE. Hip extension ROM and muscle strength and internal rotation ROM of the push-off leg significantly decreased at POST compared to that at PRE.

CONCLUSION

The total shoulder arc ROM and shoulder abductor muscle strength of the dominant sides, trunk lateral flexion ROM and muscle strength, push-off leg hip joint extension muscle strength and ROM, and internal rotation ROM were more susceptible to changes as the season progressed. In order to maintain performance and prevent a throwing disorder, it is necessary to focus on these movements during the season and to appropriately train and condition these muscle groups.

Vascularized Origami Medial Femoral Condyle Flap for Finger Joint Reconstruction

SUMMARY

Total finger joint reconstruction is challenging. Vascularized toe joint transfer is currently used for reconstruction, but it is difficult to perform, fails to achieve maximal joint flexibility, and is associated with donor-site complications. As an alternative, the authors developed a vascularized medial femoral condyle flap technique, wherein the vascularized corticoperiosteum is shaped via origami, with the donor tissue folded to fit the recipient site. In this article, the authors describe the use of this method for reconstruction of interphalangeal and metacarpophalangeal joints with a reduced range of motion. The mean age of the patients (three men and four women) was 51 years (range, 36 to 68 years), and the mean follow-up period was 3 years 1 month (range, 4 months to 5 years). In the reconstructed joints, the mean range of motion; Disabilities of the Arm, Shoulder, and Hand score; and pinch strength of the unaffected side were 55 degrees (range, 24 to 90 degrees), 2.3 (range, 0 to 6), and 98% (range, 70% to 38%), respectively. No donor-site morbidities were observed. Radiography and computed tomography scans revealed joint-like grafted tissue remodeling. The study findings suggest that the origami medial femoral condyle flap is useful for functional finger joint reconstruction. The procedure requires fabrication before grafting, but tissue harvest is relatively easy.

Safe Insertion Angle of the Suture Button to Avoid Saphenous Structure in Syndesmosis Injury

In placing the medial suture button for syndesmosis injury, the risk of great saphenous vein and saphenous nerve injury has been reported. This study aimed to determine the safe insertion angle of the guide pin to avoid saphenous structure injury during suture button fixation. The incidence of saphenous structure injury was investigated using 8 legs of cadavers. The greater saphenous vein was depicted on the skin using near-infrared light (VeinViewer® Flex) and the distance between the greater saphenous vein and the posterior edge of the tibia at levels of 10, 20, and 30 mm from the joint line of the tibiotalar joint was measured in the 60 legs of healthy participants. On computed tomography (CT) images, the angles between the greater saphenous vein and transmalleolar axis at levels of 10, 20, and 30 mm from the joint line of the tibiotalar joint were measured. The cadaveric study revealed that the percentages of contact with the saphenous nerve were 8.3% to 16.7%. Using near-infrared light, the vein and tibia distance was 32.9 ± 6.8 mm of 10 mm, 26.6 ± 6.4 mm of 20 mm, and 20.4 ± 6.4 mm of 30 mm. The angle between the vein and transmalleolar axis was 1.0° to 9.4°, and more proximal, the angle was smaller. The veins depicted by near-infrared light can be a landmark to identify great saphenous vein, and injury of the saphenous structure can be prevented using VeinViewer Flex or considering the insertion angle defined in this study when placing the suture button for syndesmosis injuries.Level of Evidence: Level IV.

Quantitative evaluation of calcaneofibular ligament injury on the oblique coronal view of magnetic resonance imaging in chronic lateral ankle instability

BACKGROUND

In the treatment of chronic lateral ankle instability (CLAI), the repair of the calcaneofibular ligament (CFL) and anterior talofibular ligament (ATFL) is still being discussed, possibly due to the difficulty in assessing CFL injuries. In particular, it is challenging to evaluate the extent of CFL deficiency quantitively. We hypothesized that CFL tension change would alter morphology of the CFL on magnetic resonance imaging (MRI) and that measuring this morphological change allows assessing CFL injury quantitatively. Thus, this study aimed to analyze the feasibility of quantitatively assessing CFL injuries using MRI.

METHODS

Sixty-four ankles with CLAI were included and divided into two groups: with (ATFL and CFL group, 31 ankles) or without CFL repair (ATFL group, 33 ankles) in addition to arthroscopic ATFL repair. The angle between the CFL and calcaneal axis (CFLCA) and the bending angles of the CFL was defined as the flexed CFL angle (FCA) were measured on the oblique CFL view of preoperative MRI. The diagnostic abilities of these angles for CFL injury and correlations between these angles and stress radiographs were analyzed.

RESULTS

The sensitivity and specificity of CFLCA were 86.7 % and 88.7 %, and those of FCA were 63.3 % and 77.4 %, respectively. The combination of CFLCA and FCA improved the sensitivity to 93.3 %. The cutoff points of CFLCA and FCA were 3.8° and 121.2°, respectively. There were significant moderate and weak correlations between the talar tilting angle and CFLCA or FCA (rs = -0.533, and rs = -0.402, respectively). The CFLCA and FCA were significantly smaller in the ATFL and CFL group than those in the other groups.

CONCLUSIONS

Measurement of CFLCA and FCA in oblique CFL view on MRI could be useful for the quantitative evaluation of CFL injury in patients with CLAI． LEVEL OF EVIDENCE: Level IV. case-control study.

MRI signal intensity ratio reflects the quality of the anterior talofibular and calcaneofibular ligaments in patients with chronic lateral ankle instability

BACKGROUND

Ligament quality can affect clinical outcomes of ligament repair in chronic lateral ankle instability (CLAI). Magnetic resonance imaging (MRI) is used to assess the morphological changes of ligaments, but the measurement of signal intensity enables quantitative evaluation, which can evaluate the degree of the ligament quality. This study aimed to evaluate the qualitative diagnostic capacity for anterior talofibular ligament (ATFL) and calcaneofibular ligament (CFL) injuries of the signal intensity on MRI.

METHODS

Thirty-eight and 20 ankles with and without CLAI, respectively, were included. The regions of interest (ROIs) were set in the ATFL, CFL, and tibialis anterior tendon (TAT) on MRI, and the signal intensities were measured. The signal intensities of the ATFL and CFL were corrected using TAT as the signal intensity ratio (SIR). The SIRs of the ATFL and CFL in the control and CLAI groups were compared. The relationship between the SIR of the ATFL and the arthroscopic findings was analyzed. Finally, the SIRs of the CFL in CLAI with and without CFL repair were compared.

RESULTS

The mean SIR of the ATFL in the CLAI group (6.1 ± 2.4) was significantly higher than that in the control (2.1 ± 0.4) (P < 0.01). The SIR of the ATFL was associated with the arthroscopic grading. The mean SIR of the CFL in the CLAI groups (4.1 ± 2.5) was significantly higher than that in the control (1.7 ± 0.4) (P < 0.01). The SIR of the CFL in patients with the requirement of the CFL repair (6.2 ± 1.9) was significantly higher than that without the CFL repair (2.1 ± 0.5) (P < 0.05).

CONCLUSIONS

The SIR is useful for evaluating the quality of the ATFL and CFL, which enables the decision of the treatment strategy of the CLAI.

Detecting side-to-side differences of lower limb biomechanics during single-legged forward landing after anterior cruciate ligament reconstruction

BACKGROUND

Motion analysis can be used to evaluate functional recovery after anterior cruciate ligament (ACL) reconstruction; however, the biomechanics parameters of the lower limb that are specifically altered in ACL-reconstructed knees compared to the contralateral side are not well understood. This retrospective study aimed to compare side-to-side differences in lower limb biomechanics during the first 100 milliseconds (ms) after initial contact in a single-leg forward landing task.

METHODS

Using three-dimensional motion analysis, lower joint kinematic and kinetic variables were measured 8-10 months postoperatively in 22 patients who had undergone ACL reconstruction. We determined side-to-side differences in lower limb biomechanics over the 100-ms timeframe after landing, and receiver operating characteristic (ROC) curve analyses were performed to calculate the area under the curve (AUC) for parameters showing significant side-to-side differences.

RESULTS

During the 100-ms timeframe after landing, 58 kinematic and kinetic items showed significant side-to-side differences. Side-to-side differences in lower limb biomechanics over the 40-ms timeframe after landing existed. The ROC curve analysis identified 11 items with AUC values ≥ 0.70, including hip flexion, abduction moment, and knee joint power, and their AUC values were not significantly different.

CONCLUSION

Hip flexion/abduction moment and knee power after GRF max could be used as outcomes for assessing functional recovery in patients who have undergone ACL reconstruction.

Investigating the subchondral trabecular bone microstructure in patients with osteonecrosis of the femoral head using multi-detector row computed tomography

OBJECTIVES

To analyse the microstructural changes of subchondral trabecular bone in patients with osteonecrosis of the femoral head (ONFH) using multi-detector row computed tomography (MDCT).

METHODS

We retrospectively investigated 76 hips in 50 patients diagnosed with ONFH between 2017 and 2021. Groups 1, 2, 3, and 4 comprised hips without ONFH, ONFH without femoral head collapse (FHC), ONFH with mild collapse (<2 mm), and ONFH with severe collapse (>2 mm), respectively. All patients underwent MDCT, and the subchondral trabecular bone microstructure was assessed. Regions of interests were set at the lateral boundary of the femoral head necrotic lesion and centre of the acetabular weight-bearing portion.

RESULTS

In both the femoral head and the acetabular regions, there were significant differences in Groups 2 and 3 compared to Group 1, with increased volumetric bone mineral density and apparent bone volume fraction, and more plate-like with increased connectivity, indicating that osteosclerotic changes were occurring.

CONCLUSIONS

In both the femoral head and the acetabular regions, osteosclerotic changes of subchondral trabecular bone microstructure were present before FHC.

Morphology and deformity of the distal phalanx in hallux valgus

BACKGROUND

Studies have shown that the first metatarsal contributes to hallux valgus. The proximal phalanx, another factor that defines the hallux valgus angle, also contributes to the development of hallux valgus. There have been no reports on the use of computed tomography to evaluate bone morphology of the proximal phalanx. The purpose of this study was to analyze the morphology and deformity of the proximal phalanx and its relationship to hallux valgus using computed tomography, and to consider the indications for proximal phalanx surgery in hallux valgus.

METHODS

Patients who consulted at our clinic for foot and ankle disorders and underwent both weight-bearing radiography and computed tomography between May 2019 and March 2022 were included in the study. The hallux valgus angle, sesamoid subluxation, first metatarsal length, proximal phalanx length, metatarsal-proximal phalanx ratio, proximal phalanx valgus angle, metatarsal-proximal phalanx angle, proximal phalanx rotation angle, and distal phalanx-proximal phalanx angle were measured. These parameters were compared between the hallux valgus and control groups. In the hallux valgus group, the hallux valgus and proximal phalanx valgus angles were measured and compared using weight-bearing radiographs.

RESULTS

A total of 83 feet in 65 patients were diagnosed with hallux valgus (hallux valgus group; mean age of 68.0 ± 13.8 years) and 30 feet in 22 patients without hallux valgus (control group; mean age of 67.0 ± 25.8 years) were included in the study. The proximal phalanx length, metatarsal-proximal phalanx ratio and angle, and distal phalanx-proximal phalanx angle were significantly greater in the hallux valgus group than in the control group. However, the proximal phalanx valgus and rotation angles were not significantly different between the groups.

CONCLUSION

Since there was no significant difference in the proximal phalanx morphology, except length, between the hallux valgus and control groups, the indications for osteotomy of the proximal phalanx should be carefully considered.

Development of osteophytes and joint space narrowing is associated with cartilage degeneration of the osteochondral fragment in the osteochondral lesion of the talus

BACKGROUND

During surgery for osteochondral lesions of the talus (OLT), preservation or excision of the osteochondral fragment is chosen based on the cartilage condition which influences the indication and clinical outcomes of surgical treatments. However, it is difficult to predict arthroscopic and histological findings of the cartilage on osteochondral fragments by radiographic evaluation. We focused on osteoarthritis (OA) changes on plain radiographs to predict the cartilage condition of the OLT. This study aimed to evaluate whether OA changes, including osteophyte and joint space narrowing, could predict arthroscopic and histological findings of the cartilage in OLT.

METHODS

Seventy ankles with OLT were included in this study. Osteophytes and joint space narrowing were scored on plain radiographs. Lesion sizes were measured on computed tomography images. The cartilage surfaces of fragments were arthroscopically assessed using the International Cartilage Repair Society (ICRS) grade. Biopsy specimens from 32 ankles were histologically analyzed using the Mankin score. The relationships between OA scores, lesion size, ICRS grades, and Mankin score were analyzed.

RESULTS

OA changes were frequently observed with increasing ICRS grades, especially in the medial tibiotalar joint. OA scores in patients with ICRS grade 1 were significantly lower than those in ICRS grades 2,3, and 4. The lesion sizes in patients with ICRS grade 3 and 4 were significantly smaller than those in patients with ICRS grade 1 and 2. Histological analysis showed increasing Mankin scores as the ICRS grade worsened. A mild correlation existed between the OA and Mankin scores (rs = 0.494).

CONCLUSIONS

OA changes, such as osteophyte formation and joint space narrowing, are associated with arthroscopic findings of the articular surface and cartilage degeneration in osteochondral fragment in OLT. Articular cartilage conditions can be predicted by OA changes on plain radiographs, which is useful for choosing the appropriate treatment for patients with OLT.

LEVEL OF EVIDENCE

Level Ⅳ, case series.

Relationship of Chronic Ankle Instability With Foot Alignment and Dynamic Postural Stability in Adolescent Competitive Athletes

Background

Competitive adolescent athletes should be aware of the early signs of chronic ankle instability (CAI) and the connection between the condition and performance.

Purpose

To investigate whether CAI is related to foot alignment and morphology as well as dynamic postural stability after a jump landing among adolescent competitive athletes with and without a history of a lateral ankle sprain and CAI.

Study Design

Cross-sectional study; Level of evidence, 3.

Methods

Between July 2020 and August 2021, adolescent competitive athletes (N = 85; n = 49 boys; n = 36 girls) were classified into 3 groups using Cumberland Ankle Instability Tool (CAIT) scores: healthy athletes (n = 55), coper athletes (n = 19), and athletes with CAI (n = 11). Results of foot alignment assessments involving the leg-heel angle (LHA) and navicular height, intrinsic foot muscle morphology, dynamic postural stability index (DPSI), and other parameters were compared among the 3 groups. The relationship between the CAIT score and the LHA and dynamic postural stability and instability were examined using multiple linear regression.

Results

Compared with the healthy group, the CAI group had a significantly greater LHA (8.73°± 3.22° vs 6.09°± 3.26°; P < .05), higher DPSI (0.336 ± 0.046 vs 0.298 ± 0.035), and higher vertical stability index (0.303 ± 0.048 vs 0.264 ± 0.037; P < .05 for all). Multiple regression analysis showed that the LHA (β = -0.228; P = .033) and DPSI (β = -0.240; P = .025) were significantly associated with the CAIT score .

Conclusion

Valgus rearfoot alignment and poorer dynamic postural control were associated with CAI among adolescent athletes.

Effect of limb alignment correction on medial meniscus extrusion under loading condition in high tibial osteotomy

Background

This study aimed to investigate the effect of high tibial osteotomy (HTO) on medial meniscus extrusion (MME) and the association between the changes in limb alignment and MME under weight-bearing (WB) conditions after HTO.

Methods

We included 17 patients with knee osteoarthritis (OA) who underwent HTO. MME was evaluated using ultrasonography in supine and unipedal standing positions. Knee alignment was evaluated radiographically using WB, whole-leg radiographs with the hip-knee-ankle angle (HKAA), percentage of the mechanical axis (%MA), medial proximal tibial angle (MPTA), and joint line convergence angle (JLCA). All measurements were performed serially at four time points: preoperative and 3, 6, and 12 months postoperative. Clinical outcomes were assessed by knee injury and osteoarthrosis outcome score (KOOS) and visual analogue scale (VAS) value for pain.

Results

Mean MME in the WB position was significantly greater than that in the supine position in the preoperative condition; however, MME in both supine and WB positions was significantly lowered postoperatively. The ΔMME, difference of MME between supine and WB positions, was significantly lowered postoperatively and maintained for up to 1 year. MME change in the WB position between preop and postoperative conditions was significantly correlated with change in HKAA and %MA at 1 year postoperative. KOOS and VAS score were significantly improved after HTO.

Conclusions

HTO correcting varus alignment can decrease MME in WB position and minimise the change in MME between supine and WB positions. The changes in MME after HTO were correlated with changes in the mechanical alignments.

Evaluation of meniscus extrusion during stair ambulation in healthy volunteers using dynamic ultrasonography: a feasibility study

PURPOSE

This study aimed to investigate the feasibility of evaluating medial meniscus extrusion (MME) during stair ambulation.

METHODS

Twenty healthy young participants (mean age, 22.4 ± 0.9 years) were recruited for this cross-sectional study. Synchronization between the three-dimensional motion system and ultrasonography was used to quantify the extent of meniscal extrusion and knee angles during different tasks, including gait, stair ascent, and stair descent. In particular, ultrasonography was used to record the movements of both the middle and posterior segments of the meniscus to obtain detailed information about these movements in relation to the knee angle. The difference between the maximum MME and the MME at the initial contact (ΔMME) was evaluated during each task in the stance phase.

RESULTS

Visualization of the meniscus in the middle segment was limited with increasing knee flexion angle, whereas the posterior segments were visible during all tasks. ΔMME of the posterior segment during stair ascent and descent was higher than that during gait (gait: 0.68 ± 0.20 mm, ascent: 1.00 ± 0.39 mm, descent: 0.90 ± 0.27 mm, gait-ascent: p = 0.009, gait-descent: p = 0.004).

CONCLUSIONS

Evaluation that includes the posterior segment enables visualization of the medial meniscus and detection of its specific behavior during stair ambulation. These findings demonstrate the feasibility of evaluating meniscus dynamics during stair ambulation, and could contribute to a better understanding of these dynamics.

Immediate Closed Reduction Technique for Cervical Spine Dislocations

STUDY DESIGN

Retrospective study.

PURPOSE

This research aimed to assess the clinical outcomes of patients with traumatic cervical spine dislocation who underwent closed reduction employing our approach.

OVERVIEW OF LITERATURE

Bedside closed reduction is the quickest procedure for repairing traumatic cervical spine dislocations; nevertheless, it also possesses the risk of neurological deterioration.

METHODS

For closed reduction, the patient's head was elevated on a motorized bed, the cervical spine was placed at the midline, traction of 10 kg was applied, the motorized bed was gradually returned to a flat position, the head was lifted off the bed, and the cervical spine was slowly adjusted to a flexed position. The weight of traction was elevated by 5-kg increments until the positional shift was attained. Subsequently, the bed was gradually tilted while traction was applied again to return the cervical spine to the midline position.

RESULTS

Of the 43 cases of cervical spine dislocation, closed reduction was carried out in 40 cases, of which 36 were successful. During repositioning, three patients experienced a temporary worsening of their neck pain and neurological symptoms that enhanced when the cervical spine was flexed. Closed reduction was conducted while the patient was awake; nevertheless, sedation was needed in three cases. Among the 24 patients whose pretreatment paralysis had been characterized by American Spinal Injury Association Impairment Scale (AIS) grades A-C, seven patients (29.2%) demonstrated an enhancement of two or more AIS grades at the last observation.

CONCLUSIONS

Our closed reduction approach safely repaired traumatic cervical spine dislocations.

Visualization of lateral meniscus extrusion during gait using dynamic ultrasonographic evaluation

PURPOSE

Medial meniscus extrusion is one of the risk factors for knee osteoarthritis (OA). However, lateral meniscus extrusion has not been discussed, and detailed information remains unknown. In particular, the lateral meniscus has high mobility and is expected to be difficult to evaluate in terms of its behavior under static conditions. Dynamic ultrasonographic evaluation was introduced to detect the dynamic behavior of the meniscus during walking. In this study, we aimed to investigate the behavior of the lateral meniscus during walking using dynamic ultrasonographic evaluation.

METHODS

Sixteen participants with knee OA were recruited in this study. The change of lateral meniscus extrusion during walking was recorded using ultrasonography. Medial and lateral meniscal extrusion during the stance phase was measured, and meniscal mobility was defined as the difference in meniscal extrusion between minimum and maximum values (mm), medial meniscal extrusion (∆MME), and lateral meniscal extrusion (∆LME), respectively. The walking cycle and gait forms of lateral thrust were also evaluated using three-dimensional motion analysis systems and analyzed in terms of the correlation with ∆MME and ∆LME.

RESULTS

The lateral meniscus was depicted in the articular plane, and extrusion decreased during the stance phase of the gait cycle. The ∆LME was significantly higher than the ∆MME (p < 0.01). There was a significant positive correlation between ∆LME and lateral thrust (r = 0.62, p < 0.05).

CONCLUSIONS

We found that dynamic ultrasonographic evaluation can be used to visualize lateral meniscus extrusion during walking, and that its behavior is correlated to the degree of lateral thrust.