Relationship between increased knee joint line obliquity after medial open-wedge high tibial osteotomy and patient-reported outcome measures

INTRODUCTION

This study evaluated the correlation between postoperative knee joint line obliquity after medial open-wedge high tibial osteotomy and patient-reported outcome measures excluding excessively overcorrected knees. This study further identified preoperative radiological factors related to the increased postoperative knee joint line obliquity.

MATERIALS AND METHODS

We retrospectively evaluated patients who underwent medial open-wedge high tibial osteotomy between March 2013 and March 2021. Postoperative excessively overcorrected knees with hip-knee-ankle angle > 7° were excluded. We investigated radiological parameters and patient-reported outcome measures preoperatively and at the last follow-up. The following radiologic parameters were measured: hip-knee-ankle angle, weight-bearing line ratio, mechanical medial proximal tibial angle, mechanical lateral distal femoral angle, lateral distal tibial angle, joint line convergent angle, knee joint line obliquity, ankle joint line obliquity, hip abduction angle, tibial posterior slope, Carton-Deschamps index, and patella tilting angle. Clinical outcomes were evaluated using Japanese knee outcome measures. This assessment criterion is based on the Western Ontario McMaster Universities Arthritis Index and MOS Short Form 36. Multiple regression analysis was performed to evaluate the association between postoperative knee joint line obliquity and patient-reported outcome measures or preoperative radiological factors (P < .05).

RESULTS

A total of 52 knees were included. The mean age at the time of the surgery was 61.6 ± 9.0 years and the mean follow-up period was 30.6 ± 10.1 months. Increased postoperative knee joint line obliquity was associated with lower Japanese knee outcome measures. The preoperative hip-knee-ankle angle was significantly associated with postoperative knee joint line obliquity.

CONCLUSIONS

Increased knee joint line obliquity after medial open-wedge high tibial osteotomy is associated with inferior clinical outcomes. Care should be given to the center of the rotational angulation in around-knee osteotomy to avoid postoperative increased knee joint line obliquity.

LEVEL OF EVIDENCE

Retrospective comparative study, Level III.

Minimizing the risk of injury to the popliteal artery during pullout repair of medial meniscus posterior root tears: A cadaveric study

Background

The purpose of this study was to investigate the positional effect of guide pins used in the transtibial pullout repair of medial meniscus posterior root tears on the popliteal artery.

Methods

We used eight cadaveric knees. Two 2.4-mm guide pins were inserted into the posterior root of the medial meniscus at 50° to the articular surface from the medial edge of the tibial tuberosity (anteromedial group) and the anterior edge of the medial collateral ligament (posteromedial group) using an aiming guide placed at the posterior root attachment of the medial meniscus from the anteromedial portal. The posterior capsule was dissected, and the popliteal artery was identified. The positional effect of the guide pins on the popliteal artery was photographed arthroscopically at 0°, 30°, 60°, and 90° knee flexion angles. The popliteal artery diameter and the minimum distance between the popliteal artery center and the guide pin tip were measured.

Results

At 90° knee flexion, most of the guide pins in the anteromedial (6 knees; 75 %) and posteromedial groups (7 knees; 87.5 %) collided with the femoral intercondylar wall. The rate of collision was significantly higher at the 90° knee flexion position than that at other angles (p = 0.02). The average shortest distance between the popliteal artery center and the guide pin tip at 0° knee flexion in the posteromedial group (5.4 mm ± 3.4 mm) was significantly greater than that at other knee flexion angles, although the mean distance in the posteromedial group was so negligible that the guide pin could penetrate the popliteal artery.

Conclusions

Knee flexion at 90° causes less damage to the popliteal artery during the transtibial pullout repair of medial meniscus posterior root tears.

Less tunnel enlargement in triple-bundle versus double-bundle anterior cruciate ligament reconstruction: A randomized clinical trial

BACKGROUND

No study thus far has compared tunnel enlargement between double-bundle and triple-bundle anterior cruciate ligament reconstruction. We compared tibial tunnel enlargement and rate of tibial tunnel coalition between these two reconstructions, hypothesizing that tibial tunnel enlargement in triple-bundle reconstruction is less than that in double-bundle reconstruction, and that the tunnel coalition rate is equal between the two procedures.

METHODS

This prospective randomized clinical trial included 25 patients who underwent computed tomography 2 weeks and 1 year postoperatively. Eleven patients underwent double-bundle anterior cruciate ligament reconstruction and 14 underwent triple-bundle anterior cruciate ligament reconstruction. Tunnel positions and tunnel coalition at the tibial tunnel aperture were assessed using three-dimensional computed tomography. Tunnel enlargement rate was calculated by measuring the sagittal and axial widths of the tibial bone tunnel 10 mm from the tibial tunnel aperture. These parameters were then compared between the groups.

RESULTS

The changes in tunnel positions and tunnel coalitions between groups were not significantly different. On both sagittal and axial views, the tunnel enlargement rates of the medial and lateral sections of the anteromedial bundle in the triple-bundle group were significantly smaller than those in the double-bundle group (sagittal view, p = 0.02 and < 0.01, respectively; axial view, p = 0.02 and ≤ 0.05, respectively). The groups did not differ significantly in terms of posterolateral tunnel enlargement.

CONCLUSION

Tunnel widening in the medial and lateral sections of the anteromedial bundle-associated tibial tunnel in triple-bundle anterior cruciate ligament reconstruction was smaller than that of double-bundle reconstruction. The tunnel coalition rates between the two reconstructions were not significantly different.

The function of cruciate ligaments in bi-cruciate retaining Total knee arthroplasty with asymmetrical design

BACKGROUND

Bi-cruciate retaining total knee arthroplasty with an asymmetrical design may improve knee function and clinical outcomes. This study aimed to compare the kinematics, anteroposterior laxity, and in situ forces of the anterior and posterior cruciate ligaments of knees subjected to this treatment with those of healthy knees.

METHODS

Seven fresh-frozen cadaveric knees were tested using a robotic/universal force-moment sensor system. The kinematics during passive flexion-extension motion and anteroposterior laxity for native knee, treated knee, and treated knee with cruciate ligament transection states were investigated. The motions of the intact and treated knees during each test were repeated after anterior/posterior cruciate ligament transection to calculate the in situ force in the ligaments.

FINDINGS

The screw-home movement of normal knees disappeared after treatment. The in situ force of the anterior cruciate ligament in treated knees was higher than that in intact knees at ˃15° during flexion and at 60° and 90° against an anterior force. The in situ force of the posterior cruciate ligament in treated knees was higher at 0°, 15°, and 30° during flexion and at all flexion angles against a posterior force.

INTERPRETATION

The screw-home movement of normal knees decreased, and the in situ force of the anterior and posterior cruciate ligaments increased after treatment.

Risk factors of lower extremity injuries in youth athletes

Objective

Lower extremity sports injuries frequently occur during an individual's growth period. The object of the current study was to analyse the risk factors for lower extremity sports injuries for youth athletes. The secondary objective was to clarify the factors related to new injuries after a lower extremity injury.

Methods

We extracted information on youth athletes (aged 10-15 years) with sports-related disorders. Background data and injury situations were collected via a specific application. During the follow-up period, new injuries were also recorded. The athletes were divided into two groups according to injury location (lower extremity or other). We performed a multiple logistic regression analysis to clarify the association between injury location and background data.

Results

1575 complaints of lower extremity disorders and 328 complaints in other body parts were registered. According to the multiple regression analysis, practice time per week was significantly shorter for the lower extremity group than the other locations group (OR 0.98; 95% CI 0.963 to 0.999). Athletes whose future goal was at the recreational level had a significantly low incidence of new injuries after experiencing lower extremity disorders.

Conclusion

The practice environments and psychological factors should receive more attention to prevent lower extremity injuries.

A Comparative Study of Foot Range of Motion and Activities of Daily Living Status of Patients Following Ankle Arthrodesis and Tibiotalocalcaneal Arthrodesis

Subtalar arthrodesis in addition to ankle arthrodesis (AA) should have effect on foot motion and functional capabilities pertaining to activities of daily living (ADL); however, it is not well characterized. We compared the foot range of motion and ADL-related functional capabilities between patients who had undergone AA and tibiotalocalcaneal arthrodesis (TTC). Twenty-one AA patients and 10 TTC patients were enrolled. Foot sagittal motion arc was measured by radiographs. Patient satisfaction, ADL, footwear restriction, and rating scale scores were compared between the 2 groups. The mean sagittal motion arc in the AA group (23.5 ± 6.2°) was significantly greater than that in the TTC group (15.3 ± 3.5°). Patient satisfaction and overall ADL status was comparable in the 2 groups. Difficulties in climbing stairs, wearing rubber boots, and sitting in cross-legged position were more frequently reported in the TTC group. Our findings may be valuable for both surgeons and patients in predicting post-treatment ADL status and avoiding over expectations.

The Role of the Medial Meniscus in Anterior Knee Stability

BACKGROUND

Few studies have compared the force distribution between the anterolateral, posterolateral, and medial structures of the knee.

PURPOSE

To investigate the important structures in an intact knee contributing to force distribution in response to anterior tibial load.

STUDY DESIGN

Controlled laboratory study.

METHODS

Nine fresh-frozen cadaveric knee specimens underwent robotic testing. First, 100 N of anterior tibial load was applied to the intact knee at 0°, 15°, 30°, 60°, and 90° of knee flexion. The anterior cruciate ligament (ACL), anterolateral capsule, lateral collateral ligament, popliteal tendon, posterior root of the lateral meniscus, superficial medial collateral ligament, posterior root of the medial meniscus (MM), and posterior cruciate ligament were then completely transected in sequential order. After each transection, the authors reproduced the intact knee motion when a 100-N anterior tibial load was applied. By applying the principle of superposition, the resultant force of each structure was determined based on the 6 degrees of freedom force/torque data of each state.

RESULTS

At every measured knee flexion angle, the resultant force of the ACL was the largest of the tested structures. At knee flexion angles of 60° and 90°, the resultant force of the MM was larger than that of all other structures with the exception of the ACL.

CONCLUSION

The MM was identified as playing an important role in response to anterior tibial load at 60° and 90° of flexion.

CLINICAL RELEVANCE

In clinical settings, the ACL of patients with a poorly functioning MM, such as tear of the MM posterior root, should be monitored considering the large resultant force in response to an anterior tibial load.

Biomechanical Study of Syndesmotic Stability in AITFL and PITFL Injury Models

Category:

Basic Sciences/Biologics; Trauma

Introduction/Purpose:

Severe ankle syndesmotic injuries can cause not only anterior inferior tibiofibular ligament (AITFL) injury but also posterior inferior tibiofibular ligament (PITFL) injury. However, the biomechanical stability and the best surgical treatment method for PITFL injuries are unknown. This study aimed to evaluate the stability of AITFL and PITFL injury models and the treatment models with suture-button (SB) fixation, AITFL augmentation with suture-tape (aST), and PITFL augmentation with suture-tape (pST). We hypothesized that PITFL injury causes posterior instability of syndesmosis and that this can be stabilized with pST fixation

Methods:

This study was approved by our institution's ethics review board. Ten normal fresh-frozen cadaver legs (4 males and 6 females) that were donated to our university's department of anatomy were used. The specimens were tested with the application of traction and rotational forces for dorsiflexion and external and internal rotation of the ankle joint. The fibular rotational angle related to the tibia (FRA), anterior tibiofibular diastasis (aTFD), and posterior tibiofibular diastasis (pTFD) were measured using the magnetic tracking system. Intact, injured (AITFL, PITFL and IOM resection), SB fixation, SB + aST fixation, and SB + aST + pST fixation models were made and loaded with forces. One-way ANOVA was used to evaluate the relationship between the models. Post-hoc analysis of the differences between the models was performed using Dunnett's test. A p value of 0.05 was chosen as the level of significance.

Results:

In the injured model, both FRA and TFD were significantly increased compared with those of the intact model in all directions. In the SB fixation model, only FRA with an external rotation force was significantly increased compared with that of the intact model. In the SB+aST model, both FRA and aTFD were not significantly different from those in the intact model.

Conclusion:

The results of this study showed that there was external and internal rotational instability in the AITFL and PITFL injury models, while there was stability in the SB + aST model. SB fixation alone did not reduce FRA with an external rotation force and there was no significantly different FRA with an internal rotation force. With SB fixation alone, anterior instability was found to be greater than posterior stability, while aST fixation was associated with anterior stability. In this study, the change in syndesmosis stability after pST fixation was found to be restrictive.

Comparison of Treatment Methods for Syndesmotic Injuries With Posterior Tibiofibular Ligament Ruptures: A Cadaveric Biomechanical Study

Background:

Studies on ankle syndesmosis have focused on anterior inferior tibiofibular ligament (AITFL) and interosseous membrane injuries; however, the characteristics of posterior inferior tibiofibular ligament (PITFL) ruptures remain unclear.

Purpose/Hypothesis:

This study evaluated the biomechanical characteristics of syndesmotic instability caused by PITFL injury and compared various treatment methods. We hypothesized that PITFL injury would lead to syndesmotic internal rotational instability and that the stability would be restored with suture tape (ST) PITFL augmentation.

Study Design:

Controlled laboratory study.

Methods:

Ten uninjured fresh-frozen cadaveric leg specimens were tested via forces applied to the external and internal rotation of the ankle joint. The fibular rotational angle (FRA) related to the tibia, anterior tibiofibular diastasis (aTFD), and posterior tibiofibular diastasis (pTFD) were measured using a magnetic tracking system. Six models were created: (1) intact, (2) AITFL injury; (3) AITFL + PITFL injury; (4) suture button (SB) fixation; (5) SB + anterior ST (aST) fixation; and (6) SB + aST + posterior ST fixation. The FRA, aTFD, and pTFD were statistically compared between the intact ankle and each injury or fixation model.

Results:

In the intact state, the changes in FRA and aTFD were 1.09° and 0.33 mm when external rotation force was applied and were 0.57° and 0.41 mm when internal rotation force was applied. In the AITFL injury model, the changes in FRA and aTFD were 2.38° and 1.51 mm when external rotation force was applied, which were significantly greater versus intact (P = .032 and .008, respectively). In the AITFL + PITFL injury model, the changes in FRA and pTFD were 2.12° and 1.02 mm when internal rotation force was applied, which were significantly greater versus intact (P = .007 and .003, respectively). In the SB fixation model, the change in FRA was 2.98° when external rotation force was applied, which was significantly higher compared with intact (P < .001). There were no significant differences between the SB + aST fixation model and the intact state on any measurement.

Conclusion:

PITFL injury significantly increased syndesmotic instability when internal rotation force was applied. SB + aST fixation was effective in restoring syndesmotic stability.

Clinical Relevance:

These results suggest that SB + aST fixation is sufficient for treating severe syndesmotic injury with PITFL rupture.

Effect of Anterior Horn Tears of the Lateral Meniscus on Knee Stability

Background

Investigations on the biomechanical characteristics of the anterior horn of the lateral meniscus (AHLM) related to anterior cruciate ligament (ACL) tibial tunnel reaming have revealed increased contact pressure between the femur and tibia, decreased attachment area, and decreased ultimate failure strength.

Purpose/Hypothesis

The purpose of this study was to investigate the influence of a complete radial tear of the AHLM on force distribution in response to applied anterior and posterior drawer forces and internal and external rotation torques. We hypothesized that the AHLM plays an important role in knee stability, primarily at lower knee flexion angles.

Study Design

Controlled laboratory study.

Methods

A total of 9 fresh-frozen cadaveric knee specimens and a robotic testing system were used. Anterior and posterior drawer forces up to 89 N and internal and external rotation torques up to 4 N·m were applied at 0°, 30°, 60°, and 90° of knee flexion. A complete AHLM tear was then made 10 mm from the lateral border of the tibial attachment of the ACL, and the same tests performed in the intact state were repeated. Next, the recorded intact knee motion was reproduced in the AHLM-torn knee, and the change in the resultant force after an AHLM tear was determined by calculating the difference between the 2 states.

Results

In the torn AHLM, the reduction in the resultant force at 0° for external rotation torque (34.8 N) was larger than that at 60° (5.2 N; P < .01) and 90° (6.7 N; P < .01).

Conclusion

The AHLM played a role in facilitating knee stability against an applied posterior drawer force of 89 N and external rotation torque of 4 N·m, especially at lower knee flexion angles.

Clinical Relevance

This study provides information about the effects of AHLM injuries that may occur during single-bundle ACL reconstruction using a round tunnel.

Effects of the Ankle Flexion Angle During Anterior Talofibular Ligament Reconstruction on Ankle Kinematics, Laxity, and In Situ Forces of the Reconstructed Graft

BACKGROUND

This study aimed to evaluate the effects of the ankle flexion angle during anterior talofibular ligament (ATFL) reconstruction on ankle kinematics, laxity, and in situ force of a graft.

METHODS

Twelve cadaveric ankles were evaluated using a 6-degrees of freedom robotic system to apply passive plantar flexion and dorsiflexion motions and multidirectional loads. A repeated measures experiment was designed using the intact ATFL, transected ATFL, and reconstructed ATFL. During ATFL reconstruction (ATFLR), the graft was fixed at a neutral position (ATFLR 0 degrees), 15 degrees of plantar flexion (ATFLR PF15 degrees), and 30 degrees of plantar flexion (ATFLR PF30 degrees) with a constant initial tension of 10 N. The 3-dimensional path and reconstructed graft tension were simultaneously recorded, and the in situ force of the ATFL and reconstructed grafts were calculated using the principle of superposition.

RESULTS

The in situ forces of the reconstructed grafts in ATFLR 0 degrees and ATFLR PF 15 degrees were significantly higher than those of intact ankles. The ankle kinematics and laxity produced by ATFLR PF 30 degrees were not significantly different from those of intact ankles. The in situ force on the ATFL was 19.0 N at 30 degrees of plantar flexion. In situ forces of 41.0, 33.7, and 21.9 N were observed at 30 degrees of plantar flexion in ATFLR 0, 15, and 30 degrees, respectively.

CONCLUSION

ATFL reconstruction with the peroneus longus (PL) tendon was performed with the graft at 30 degrees of plantar flexion resulted in ankle kinematics, laxity, and in situ forces similar to those of intact ankles. ATFL reconstructions performed with the graft fixed at 0 and 15 degrees of the plantar flexion resulted in higher in situ forces on the reconstructed graft.

CLINICAL RELEVANCE

Fixing the ATFL tendon graft at 30 degrees of plantar flexion results in an in situ force closest to that of an intact ankle and avoids the excessive tension on the reconstructed graft.

The prevalence of posterior inferior tibiofibular ligament and inferior tibiofibular transverse ligament injuries in syndesmosis-injured ankles evaluated by oblique axial magnetic resonance imaging: a retrospective study

Background

Transverse ligament and posterior inferior tibiofibular ligament injuries have not been investigated till date because these are difficult to evaluate using standard magnetic resonance imaging. This study aimed to investigate the prevalence of transverse ligament and posterior inferior tibiofibular ligament injuries in syndesmosis-injured ankles using oblique axial magnetic resonance imaging.

Methods

The patients who were diagnosed with syndesmosis injury using magnetic resonance imaging (MRI) within 7 days of the trauma were included. Patients with concomitant fractures were excluded. A total of 34 patients (1 woman and 33 men) with an average age of 22 years (range, 14–64 years) were included. The anterior inferior tibiofibular, interosseous, transverse, and posterior inferior tibiofibular ligaments were classified as intact, partial tear, or complete tear using usual axial and oblique axial MRIs.

Results

There were 8 (23.5%) ankles with an intact, 21 (61.8%) ankles with a partially torn, and 5 (14.7%) ankles with a complete tear of transverse ligament. There were 20 (58.8%) ankles with an intact, 12 (35.3%) ankles with a partially torn, and 2 (5.9%) ankles with a complete tear of posterior inferior tibiofibular ligament. Overall, 50% of the transverse ligament injuries occurred without posterior inferior tibiofibular ligament involvement.

Conclusions

The oblique axial magnetic resonance imaging scan revealed that the prevalence of transverse ligament and posterior inferior tibiofibular ligament injuries in syndesmosis-injured ankles were 76.5 and 41.2%, respectively.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-022-05220-0.

Relationship Between Plantar Callosity and Foot Deformity in Hallux Valgus Using Weightbearing Computed Tomography

Plantar callosities under lesser metatarsals are often accompanied by the hallux valgus, and the cause of callosity is thought to be associated with the foot deformity, such as the metatarsal length discrepancy, the abnormal metatarsal head height, cavus, flat foot, and rheumatoid conditions. However, it is unclear which variable is most involved in the cause of callosity in hallux valgus deformity. To clarify the factors associated with the callosity with hallux valgus deformity, we conducted multiple image assessments based on weightbearing radiography and computed tomography. A retrospective review was performed based on the collection of clinical records from all patients with hallux valgus treated from 2010 to 2019 in our institution. We measured the hallux valgus angle, intermetatarsal angles, calcaneal pitch angles, talo-first metatarsal angles, metatarsal length, metatarsal head height, first metatarsal pronation angles, and sesamoid position with weightbearing radiography and computed tomography. We analyzed the relation between callosity formation and imaging assessments using univariate and multivariate logistic regression models. Fifty feet were retrospectively evaluated, and multiple logistic analyses by the stepwise method revealed that the first metatarsal-lateral-sesamoid distance was the only radiographical variable associated with callosity formation among all the tested variables (p < .001). As the grade of the callosity became more severe, the lateral shift of the lateral sesamoid increased. The position of the sesamoid bone appears to have a critical role in the assessment and choice of treatment protocols and further research needs to be conducted on the relationship with the position of sesamoid bone to elucidate the mechanism of callus formation.

Symptomatic ossicle lesion at the anterior tip of the medial malleolus in soccer players

BACKGROUND

Unfused accessory ossification centers in the medial ankle are sometimes misdiagnosed and should be distinguished from other bone lesions such as fracture, stress fracture, os subtibiale, or pseudoarthrosis of the medial malleolus. The purpose of this study was to report our experience in treating soccer players with bony elements in the subtibial region.

METHODS

We surgically treated seven soccer players who experienced medial ankle pain with bony fragments at the tip of the medial malleolus. Their ages were between 13 and 27 years. The mean duration from symptom onset to hospital visit was 4.7 years (range: 2 months to 14 years). The bony lesion located at the anterior tip of the medial malleolus in all patients and we diagnosed the lesion as an unfused accessory ossification center.

RESULTS

Three types of surgical treatments were performed in patients according to age, ossicle size, status of the epiphyseal plate, and degenerative changes around the lesion. Bony fusion was achieved in patients who underwent open reduction and fusion with bone graft. Patients who underwent focal drilling or removal of the bony fragment experienced improvement in symptoms, and all patients were allowed to resume their sports or full preinjury activities.

CONCLUSION

We believe that surgery is the first-line treatment for the patients with unfused accessory ossification centers with their prolonged symptom and favorable outcomes can be expected. Bony fusion should be attempted in the patients with the large ossicle especially in their growth period.

Prevalence of Multiple-Level Spondylolysis and the Bone Union Rates among Growth-Stage Children with Lower Back Pain

Introduction

Lumbar spondylolysis is usually single level, and only a few multiple-level cases have been reported. We investigated the frequency of multiple-level spondylolysis and the bone union rates among growth-stage children with lower back pain (LBP).

Methods

The subjects were growth-stage children examined for LBP between April 2013 and December 2018. All patients with LBP persisting for at least 2 weeks and severe enough to make playing sports difficult underwent lumbar plain radiogram, computed tomography, and magnetic resonance imaging. The cases diagnosed as multiple-level spondylolysis and classified as early or progressive stage received conservative treatment to achieve bone union.

Results

A total of 782 growth-stage children were examined for LBP. Of them, 243 children (31.1%) were diagnosed with lumbar spondylolysis. Of these 243 children, 23 (9.5%) children had multiple-level spondylolysis. Of the children diagnosed with multiple-level spondylolysis, most children (87.0%) had pars defects in the early or progressive stage in which bone union could be expected. Most children (78.3%) had pars defects in the terminal stage and combined with these defects, had pars defects in the early or progressive stage at a different spinal level.

Twenty children diagnosed with multiple-level spondylolysis who also had pars defects in the early or progressive stage received conservative treatment for bone union, which was achieved in 31 of 39 sites (79.5%). The bone union rate by stage was 92.9% (26 of 28 sites) in the early stage and 45.5% (5 of 11 sites) in the progressive stage.

Conclusions

In cases of multiple-level spondylolysis, bone union is likely to be achieved with conservative treatment when the pars defects are in the early or progressive stage. Therefore, the first choice of treatment should be conservative treatment to achieve bone union, the same for single-level spondylolysis.

Hamstring Graft Prepared With Suture Tape Is Effective in Anterior Cruciate Ligament Reconstruction: A Biomechanical Analysis

Purpose

To investigate the graft diameters and mechanical properties of hamstring tendons sutured using different materials and techniques.

Methods

This study used 30 fresh, frozen human cadaveric semitendinosus tendons; the free ends of 10 specimens each were sutured by 2 No. 3 braided polyester sutures with the Krackow technique (BP group), SutureTape with the Krackow technique (ST group), or SutureTape Loop with the locking SpeedWhip technique (SL group). First, the changes in graft diameter from before suturing to after suturing were investigated. Each graft was pre-tensioned to 100 N for 3 cycles and then cyclically loaded to 200 N for 200 cycles. Elongation after cyclic loading and displacement in the 200th cycle were calculated. Finally, each specimen was loaded to failure. The ultimate failure load and stiffness were analyzed. These mechanical properties were statistically analyzed using 1-way analysis of variance. The level of statistical significance was set at P < .05.

Results

In the BP group, the changes in graft diameter were significantly larger than those in the ST and SL groups (P = .001). The elongation values after 200 cycles in the BP and ST groups were 3.1 ± 2.0 mm and 5.9 ± 3.4 mm, respectively. In the SL group, elongation (7.7 ± 3.6 mm) was significantly larger compared with that in the BP group (P = .037). In contrast, displacement in the 200th cycle was significantly smaller in the ST and SL groups compared with the BP group (P = .017). No statistically significant difference was evident for the ultimate failure loads among the 3 groups (P = .543).

Conclusions

The results of this study suggest that SutureTape may be an appropriate option for preparing the hamstring graft in anatomic anterior cruciate ligament (ACL) reconstruction.

Clinical Relevance

This biomechanical study shows the effectiveness of SutureTape in ACL graft preparation. Clinically, SutureTape may be of benefit in single- or double-bundle ACL reconstruction.

Differential drivers of intraspecific and interspecific competition during malaria-helminth co-infection

Various host and parasite factors interact to determine the outcome of infection. We investigated the effects of two factors on the within-host dynamics of malaria in mice: initial infectious dose and co-infection with a helminth that limits the availability of red blood cells (RBCs). Using a statistical, time-series approach to model the within-host ‘epidemiology’ of malaria, we found that increasing initial dose reduced the time to peak cell-to-cell parasite propagation, but also reduced its magnitude, while helminth co-infection delayed peak cell-to-cell propagation, except at the highest malaria doses. Using a mechanistic model of within-host infection dynamics, we identified dose-dependence in parameters describing host responses to malaria infection and uncovered a plausible explanation of the observed differences in single vs co-infections. Specifically, in co-infections, our model predicted a higher background death rate of RBCs. However, at the highest dose, when intraspecific competition between malaria parasites would be highest, these effects of co-infection were not observed. Such interactions between initial dose and co-infection, although difficult to predict a priori, are key to understanding variation in the severity of disease experienced by hosts and could inform studies of malaria transmission dynamics in nature, where co-infection and low doses are the norm.

Quantitative Evaluation of Ankle Instability Using a Capacitance-Type Strain Sensor

BACKGROUND

Manual evaluation is an important method for assessing ankle instability, but it is not quantitative. Capacitance-type sensors can be used to measure the distance on the basis of the capacitance value. We applied the sensor to the noninvasive device for measuring ankle instability and showed its utility.

METHODS

First, 5 ankles embalmed by Thiel's method were used in an experiment using a cadaver. The capacitance-type sensor was fixed alongside the anterior talofibular ligament (ATFL) of a specially made brace, and the anterior drawer test was performed. The test had been performed for the intact ankle, with the ATFL transected and with both the ATFL and calcaneofibular ligament (CFL) transected. The anterior drawer distance was calculated by the sensor. Intra- and interinvestigator reliability were also analyzed.Next, as a clinical study, a brace with a sensor was fitted to 22 ankles of 20 patients with a history of ankle sprain. An anterior drawer test at a load of 150 N was conducted using a Telos stress device. The anterior drawer distances measured by the sensor and based on radiographic images were then compared.

RESULTS

The mean anterior drawer distances were 3.7 ± 1.0 mm for the intact cadavers, 6.1 ± 1.6 mm with the ATFL transected (P < .001), and 7.9 ± 1.8 mm with the ATFL and CFL transected (P < .001). The intrainvestigator intraclass correlation coefficients (ICCs) were 0.862 to 0.939, and the interinvestigator ICC was 0.815. In the experiments on patients, the mean anterior drawer distance measured by the sensor was 2.9 ± 0.9 mm, and it was 2.7 ± 0.9 mm for the radiographic images. The correlation coefficient between the sensor and the radiographic images was 0.843.

CONCLUSION

We quantitatively evaluated anterior drawer laxity using a capacitance-type sensor and found it had high reproducibility and strongly correlated with stress radiography measurements in patients with ankle instability. Capacitance-type sensors can be used for the safe, simple, and accurate evaluation of ankle instability.

Radiographic Evaluation of Medial Opening-Wedge High Tibial Osteotomy Using a New Internal Fixator with a Wedge-Shaped Spacer Block

We developed a new internal fixator: a rigid T: -shaped plate with locking screws and wedge-shaped spacer block for high tibial osteotomy. The purpose of the present study was to evaluate the radiographic outcome of opening-wedge high tibial osteotomy (OWHTO) using this new internal fixator. Sixty OWHTOs were performed in patients with medial compartment osteoarthritis and varus deformity (28 males and 23 females). Patients' mean age was 60.4 years. Preoperative and postoperative radiographs were obtained. The paired t-test was used to evaluate the differences over time with respect to radiographic variables. Union of the osteotomy gap was obtained in all patients, and no implant breakage was found. On anterior-posterior radiographs, a significant difference was observed (p < 0.01) between the preoperative and postoperative mean values of femorotibial angles (179.6 ± 3.2 vs. 170.6 ± 2.5 degrees), weight-bearing line ratios (23.8 ± 13.5 vs. 60.5 ± 11.5%), anatomical medial proximal tibial angles (84.8 ± 2.5 vs. 91.0 ± 2.6 degrees), and joint line coverage angles (3.6 ± 2.0 vs. 2.4 ± 1.7 degrees). On lateral radiographs, posterior tibial slopes were 11.5 ± 3.9 degrees preoperatively and 12.2 ± 4.0 degrees postoperatively (p < 0.01), and Insall-Salvati ratios were 1.04 ± 0.12 preoperatively and 1.06 ± 0.13 postoperatively (p = 0.24). Performing OWHTO using a new internal fixator with a wedge-shaped spacer achieves adequate correction of lower limb alignment without implant-related complications. This is a Level IV, case series study.

Tibiofibular Space Widening Assessment With a Ball-Tipped Probe in a Syndesmosis Injury Model

Assessment of syndesmotic instability is not precise with existing evaluation methods. This study was conducted to investigate the use of a ball-tipped probe under arthroscopy for quantitative assessment of tibiofibular space widening in a syndesmosis injury model. The test specimens were 5 uninjured ankles from Thiel-fixed cadavers of 2 male subjects and 3 female subjects of mean age of 82.4 years at death. The ball-tipped probe consisted of a metal probe having a ball at each end with diameters ranging from of 1.5 mm to 5.0 mm, in increments of 0.5 mm. The tibiofibular joint was observed arthroscopically as the largest-diameter ball probe as possible was inserted into its anterior third, middle, or posterior third portion with the ankle in natural plantarflexion or under external rotational stress. These measurements were performed for the uninjured ankle and then performed following Bassett's ligament sectioning, anterior inferior tibiofibular ligament sectioning, interosseous membrane distal 15 cm sectioning, or deltoid ligament, and posterior inferior tibiofibular ligament sectioning, with the sections added in this sequence and each followed by a similar assessment. The results of quantitative assessment of tibiofibular space widening with the ball-tipped probe in the syndesmosis injury model under arthroscopy were that the maximum possible diameter of ball probe that could be inserted was 1.5 to 2.0 mm in the uninjured state, 3.0 to 3.5 mm in the sectioned anterior inferior tibiofibular ligament model, and 5.0 mm in the severe-state model. The ball probe can serve as an effective tool for quantitative assessment of the intraoperative instability in cases of syndesmosis injury.

Nano-Arthroscopic Ultrasound-Guided Excision of Unresolved Osgood-Schlatter Disease

The nano-arthroscopic ultrasound-guided ossicle excision technique is used in the management of an unresolved Osgood-Schlatter disease. The NanoScope is inserted slightly lateral to the proximal patella tendon and moved on between the ossicle and anterior surface of the proximal tibia under ultrasonographic guidance. The 5-mm skin incision is made as a working portal on the medial side of the proximal patella tendon. The proximal border of the ossicle is clearly identified after bursectomy. Then, the ossicles are removed piece by piece using a 2-mm arthroscopic punch. During the resection, the remaining ossicle is continuously confirmed by ultrasound. Finally, the complete excision of the ossicle is shown by the nano-arthroscopic view and ultrasound. The patient is allowed to have a full weight-bearing and an unrestricted range of motion on the day of surgery. Patients are permitted to resume their sports activities without any restriction after 6 weeks. This technique is recommended to athletes who suffer from painful unresolved Osgood-Schlatter disease because of the benefits of it being a minimally invasive surgery with an early postoperative recovery.

Screw Internal Fixation and Ilizarov External Fixation: A Comparison of Outcomes in Ankle Arthrodesis

The purpose of this study was to compare the mid-term clinical outcomes between screw internal fixation and Ilizarov external fixation in patients who underwent ankle arthrodesis and to elucidate the differences between the 2 fixation methods. This study investigated 43 ankles in 41 patients who underwent ankle arthrodesis at 1 of the 2 study institutions. There were 15 men and 26 women, and their mean age was 66.2 (range 49 to 87) years. The primary disease included osteoarthritis (OA) (79%), rheumatoid arthritis (RA) (16.3%), and Charcot joint (4.7%). Patients were divided into 2 groups depending on the surgical approach: the screw group (S) and the Ilizarov group (I). The following items were evaluated and compared between the 2 groups: patient characteristics, Tanaka-Takakura classification based on preoperative plain X-ray images, duration of surgery, blood loss, surgical complications, time to start weightbearing, and the Japanese Society of Surgery of the Foot (JSSF) standard rating system for the ankle-hindfoot. Duration of surgery was significantly shorter in the S group (162.3 versus 194.9 min), and the amount of blood loss was also significantly lower in the S group (29.2 versus 97.5 ml). Preoperative JSSF scale was significantly lower in the I group (44.8 versus 33), but postoperative JSSF scale was not significantly different between the 2 groups (82.1 versus 77.9). The S group had satisfactory clinical outcomes with a shorter duration of surgery and smaller amount of blood loss than the I group. However, severe patients in the I group achieved similar treatment outcomes.

Tibial Plafond Attachment of the Posterior-Inferior Tibiofibular Ligament: A Cadaveric Study

Background:

Some recent studies have reported the role of the posterior malleolus as an attachment of the posterior-inferior tibiofibular ligament (PITFL) and suggested that even a small fragment should be fixed. However, there are few anatomic studies of the tibial plafond attachment of the PITFL.

Methods:

Seven Thiel-embalmed ankles were obtained. The margin of the distal tibial joint surface and the attachments of the superficial fiber of the PITFL (sPITFL) and the deep fiber (dPITFL) were identified. In the frontal view, the percentages of the attachments of the sPITFL and dPITFL of the mediolateral dimension of the posterior tibial plafond were measured. In the lateral view, the line that started from the proximal margin of the attachment of the sPITFL and parallel to the tibial axis was drawn, and the distance between that line and the posterior edge of the joint surface was measured (AP distance of the sPITFL). Then, the percentage of the AP distance of the sPITFL of the joint surface in the anteroposterior dimension of the tibial plafond was measured.

Results:

In the frontal view, the mediolateral distance of the attachment of the sPITFL was 5.0 mm, and that of the dPITFL was 19.5 mm. The percentage of the attachment of the sPITFL on the tibial plafond was 20.6%, and that of the dPITFL was 78.2%. In the lateral view, the average AP distance of the sPITFL was 0.5 mm, and the percentage in the anteroposterior dimension of the tibial plafond was 1.7%.

Conclusion:

The PITFL was attached to less than 10% of the anteroposterior dimension of the tibial plafond in most ankles. Conversely, the PITFL attached widely in the mediolateral dimension.

Clinical Relevance:

This study suggests that the size of the posterior malleolar fragment in the mediolateral dimension could help estimate how much of the PITFL attaches to the fragment which may have implications for ankle stability.

FRI0097 EFFECTS OF BIOLOGICAL DISEASE-MODIFYING ANTI-RHEUMATIC DRUG TREATMENT ON PHYSICAL ACTIVITY, MUSCLE POWER, AGILITY AND INHIBITION OF FALL IN PATIENTS WITH RHEUMATOID ARTHRITIS -THE 2-YEAR RESULTS

Background:

Treatment with biological DMARDs (bDMARDs) rapidly improves signs and symptoms in patients with rheumatoid arthritis (RA). The efficacy of these bDMARDs was evaluated using composite measures or biomarkers used in daily clinical practice or clinical studies. Although a rapid improvement in composite measures or biomarkers is important in the treatment of RA, the primary goal of treatment is improvement of long-term health-related quality of life (HR-QOL) [1]. HR-QOL is evaluated based on physical functions (PF) such as muscle power and agility. We reported the 1-year results of our study presented at EULAR 2019 [2]. The present study was conducted to investigate the 2-year results of our study by including more patents than those included in the previous one.

Objectives:

This study was aimed at investigating the efficacy of bDMARDs with respect to PF and fall risk in RA patients.

Methods:

At our institute, in addition to routine rheumatology evaluation, periodic evaluation of physical function is performed by staff members in our rehabilitation center in RA patients in whom the first bDMARD treatment was initiated in Oct. 2015–Feb. 2018. In total, 41 cases were registered in this study. Evaluation of PF included evaluation of muscle power [grasping power (GP) and knee extension power (KEP)]; agility [time up and go test (TUG) and 10-m walking time (10 mW)]; and a questionnaire using modified HAQ, portable fall risk index [3], and the 25-question geriatric locomotive function scale (locomo25) [4] at baseline (BL), which implies the time at the initiation of bDMARD treatment, i.e., 1, 3, 6, 12, and 24 months. Disease activity of RA was evaluated at the same time points. Although 2 years had elapsed from BL in 37 patients, 13 patients dropped out from the evaluation of physical function owing to cessation of bDMARD treatment, rejection of evaluation for physical function, or major joint surgery performed in a patient. The results of 24 patients who completed the evaluation at 24 months were investigated in this study.

Results:

Baseline characteristics of the 24 patients were as follows: mean age 60.8 years, RA duration 12.3 years, mean SDAI 19.0, and mean CRP level 2.1 mg/dl. The bDMARDs used in the study were abatacept in 7 patients, adalimumab in 4 patients, tocilizumab in 4 patients, golimumab in 4 patients, etanercept in 3 patients, certolizumab in 1 patient, and an infliximab biosimilar in 1 patients. Data are presented as mean values at BL and at 1, 3, 6, 12, and 24 months (Fig.1). SDAI and CRP levels were significantly improved at and after 1 month. GP and KEP were significantly improved at and after 3 and 6 months. TUG and 10 mW results were significantly improved at and after 3 and 6 months. Modified HAQ results were significantly improved at and after 3 months. Locomo25 scores were significantly improved at and after 1 month. Portable fall risk index values were significantly improved at and after 12 months.

Conclusion:

Although there was a rapid improvement in the signs and symptoms of RA after the initiation of bDMARD treatment, improvement in PF was slightly delayed. Significant improvement of muscle power and agility was achieved after 3–6 months onward. Inhibition of fall risk was achieved at and after 12 months after the initiation of bDMARD treatment. These results suggest that physiotherapy plays a vital role in RA patients who undergo treatment with bDMARDs to gain more rapid improvement of PF.

References:

[1]Smolen JS et al. Ann Rheum Dis, 2016.

[2]Hirano Y et al. Ann Rheum Dis, suppl. 2, 2019.

[3]Toba K et al. Jpn J Geriat, 2005.

[4]Seichi A at al. J Orthop Sci, 2012.

Disclosure of Interests:

Yuji Hirano Speakers bureau: Tanabe-Mitsubishi, Pfizer, Eisai, Abbie, Chugai, Bristol-Meyers, Jansen, Astellas, UCB, Eli-Lilly, Asahikasei, Daiichi-Sankyo, Amgen, Ayako Morisaka: None declared, Hironobu Kosugiyama: None declared, Shiori Inuzuka: None declared, Takeshi Kamiya: None declared, Hiroyuki Mori: None declared, Naohito Morishima: None declared, Tomoji Ishikawa: None declared

Nontraumatic Chronic Subcutaneous Extensor Digitorum Longus Tendon Rupture in a Recreational Runner: A Case Report

CASE

Nontraumatic chronic subcutaneous rupture of the extensor digitorum longus (EDL) tendon is rare. A 66-year-old man, recreational runner, suddenly injured his EDL tendon while walking. We surgically reconstructed the ruptured EDL tendon with a free palmaris longus tendon graft. During the surgery, an osteophyte was found to have penetrated the ankle joint capsule and was considered the cause of the tendon rupture. Active toe extension was restored, and the patient completed a 10-km race at 2 months postoperatively.

CONCLUSION

EDL tendon reconstruction using a free palmaris longus tendon graft is an effective surgical option for athletes.

Morphological variations of the human talus investigated using three-dimensional geometric morphometrics

INTRODUCTION

The shape of the talus determines the positional and kinematic features of the subtalar, talonavicular, and talocrural joints during walking. Thus, detailed knowledge of the pattern of sexual dimorphism of the human talus may be useful for revealing the pathogenetic mechanism of foot and knee disorders, which are more prevalent in females. The aim of this study was to characterize and visualize the three-dimensional shape variations of the talus in relation to sex and age using geometric morphometrics.

MATERIALS AND METHODS

Computed tomography images of 56 feet without talar injuries or disorders were used in this study. Thirty-seven anatomical landmarks were identified on a bone model of the talus to calculate principal components (PCs) of shape variations among specimens. PC scores were compared between sexes, and their correlations with age were also investigated.

RESULTS

The female talus had a longer neck and narrower head width than the male talus. The superior trochlea was tilted more laterally in the frontal plane in females. Furthermore, the female talar head was more twisted and was more elongated in the dorsoplantar direction.

CONCLUSIONS

Morphological features of the talus in females could alter the subtalar and talonavicular joint kinematics during walking and could be a structural factor in the pathogenetic mechanism underlying foot and knee disorders. This study contributes to the comprehensive understanding of shape variations in the human talus.

Effect of Initial Graft Tension During Anterior Talofibular Ligament Reconstruction on Ankle Kinematics, Laxity, and In Situ Forces of the Reconstructed Graft

BACKGROUND

Although a variety of surgical procedures for anterior talofibular ligament (ATFL) reconstruction have been reported, the effect of initial graft tension during ATFL reconstruction remains unclear.

PURPOSE/HYPOTHESIS

This study investigated the effects of initial graft tension on ATFL reconstruction. We hypothesized that a high degree of initial graft tension would cause abnormal kinematics and laxity.

STUDY DESIGN

Controlled laboratory study.

METHODS

Twelve cadaveric ankles were tested with a robotic system with 6 degrees of freedom to apply passive plantarflexion and dorsiflexion motions and a multidirectional load. A repeated measures experiment was designed with the intact ATFL, transected ATFL, and reconstructed ATFL at initial tension conditions of 10, 30, 50, and 70 N. The 3-dimensional path and reconstructed graft tension were simultaneously recorded, and the in situ forces of the ATFL and reconstructed graft were calculated with the principle of superposition.

RESULTS

Initial tension of 10 N was sufficient to imitate normal ankle kinematics and laxity, which were not significantly different when compared with those of the intact ankles. The in situ force on the reconstructed graft tended to increase as the initial tension increased. In situ force on the reconstructed graft >30 N was significantly greater than that of intact ankles. The in situ force on the ATFL was 19 N at 30° of plantarflexion. In situ forces of 21.9, 30.4, 38.2, and 46.8 N were observed at initial tensions of 10, 30, 50, and 70 N, respectively, at 30° of plantarflexion.

CONCLUSION

Approximate ankle kinematic patterns and sufficient laxity, even with an initial tension of 10 N, could be obtained immediately after ATFL reconstruction. Moreover, excessive initial graft tension during ATFL reconstruction caused excessive in situ force on the reconstructed graft.

CLINICAL RELEVANCE

This study revealed the effects of initial graft tension during ATFL reconstruction. These data suggest that excessive tension during ATFL reconstruction should be avoided to ensure restoration of normal ankle motion.

Denosumab prevents periprosthetic bone mineral density loss in the tibial metaphysis in total knee arthroplasty

BACKGROUND

Periprosthetic bone quality is one of the most important factors preventing early prosthesis migration and long-term failure. Although denosumab, which binds to the receptor activator of nuclear factor kappa-B ligand (RANKL), has been linked with periprosthetic bone mineral density (BMD), the effectiveness of denosumab against bone loss remains unclear. We hypothesized that denosumab treatment after total knee arthroplasty (TKA) could prevent periprosthetic bone resorption.

METHODS

In this prospective cohort study, 28 patients with primary knee osteoarthritis were divided into two groups: denosumab (denosumab and vitamin D) and control (vitamin D only) groups. All patients underwent TKA with the same implant model and received medication after surgery. We used dual-energy X-ray absorptiometry to measure periprosthetic BMD after TKA.

RESULTS

In the control group, the BMD of the proximal medial tibia decreased drastically at 12 months after TKA (-19.7%). Denosumab treatment significantly preserved this BMD loss (0.7%). The linear regression analysis revealed that denosumab intervention had the highest significantly positive relationship with BMD.

CONCLUSIONS

Our results indicate that denosumab treatment significantly reduces periprosthetic BMD loss, even at the early stages after TKA. This therapeutic strategy may facilitate early stable fixation of the prosthesis which, in turn, may help to prevent early implant migration and reduce the need for revision surgery.

Sex- and age-related morphological variations in the talar articular surfaces of the calcaneus

BACKGROUND

The prevalence of foot pathologies, such as flatfoot deformity and hallux valgus, is higher in women and increases with age. It has been reported that these types of foot disorders may also be linked to excessive mobility of the subtalar joint to the eversion direction during weight bearing. Given that the mobility of the joint is determined by its articular morphology, sex- and age-related variations in the subtalar articular surface morphology are possible. The purpose of this study was to investigate the orientation and the curvature radii of the talar articular facets of the calcaneus in relation to age and sex using three-dimensional computer tomography.

METHODS

Fifty-six feet without subtalar injuries or disorders were included in this study. The orientations of the talar articular surfaces of the calcaneus were quantified in the sagittal and coronal planes. The curvature radii of the articular surfaces of the calcaneus were also assessed based on the approximations of the sphere surfaces.

RESULTS

The talar articular surface was oriented more anteriorly and medially in the females than in the males. The curvature radius of the calcaneal posterior facet in the females exhibited a positive correlation with age, indicative of increased articular surface flattening.

CONCLUSIONS

The morphological features of the female calcaneus could induce excessive eversion and could lead to a higher prevalence of foot disorders, including flatfoot and hallux valgus, in elderly females. This study contributes to an understanding of the sexual dimorphism of the articular surfaces of the calcaneus and provides insight into the mechanisms that underline various foot disorders.

Three-Dimensional Morphological Variations of the Human Calcaneus Investigated Using Geometric Morphometrics

The shape of the calcaneus determines the mechanical interaction of the foot with the ground during the heel-strike in human walking. Detailed knowledge of the pattern of sexual dimorphism of the human calcaneus could help to clarify the pathogenetic mechanism of foot and knee disorders, which are more prevalent in females. Therefore, the aim of this study was to characterize and visualize the three-dimensional shape variations of the calcaneus in relation to sex and age using geometric morphometrics. Computed tomography images of 56 feet without subtalar injuries or disorders were used in this study. Thirty-seven anatomical landmarks were identified on the bone model of the calcaneus to calculate principal components (PCs) of shape variations among specimens. The PC scores were compared between males and females, and their correlations with age were also analyzed. The female calcaneus was longer in length and shorter in height than that of males. The medial process of the calcaneal tuberosity in females was more inferiorly projected and the tuberosity was shifted more laterally. Also, the calcaneus was wider and the sustentaculum tali thickened with aging. Female structural features of the calcaneus alter the kinematics of the foot during walking and could be a structural factor in foot and knee disorders. This study contributes to a comprehensive understanding of shape variations in the human calcaneus. Clin. Anat., 33:751-758, 2020. © 2019 Wiley Periodicals, Inc.

Can an insole for obese individuals maintain the arch of the foot against repeated hyper loading?

BACKGROUND

Insoles are often applied as preventive therapy of flatfoot deformity, but the therapeutic effects on obese individuals are still controversial. We aimed to investigate the effect of insole use on time-dependent changes in the foot arch during a repeated-loading simulation designed to represent 20,000 contiguous steps in individuals with a BMI value in the range of 30-40 kg/m2.

METHODS

Eighteen cadaveric feet were randomly divided into the following three groups: normal, obese, and insole. Ten thousand cyclic loadings of 500 N (normal group) or 1000 N (obese and insole groups) were applied to the feet. We measured time-dependent change in arch height and calculated the bony arch index (BAI), arch flexibility, and energy absorption.

RESULTS

The normal group maintained more than 0.21 BAI, which is the diagnostic criterion for a normal arch, throughout the 10,000 cycles; however, BAI was less than 0.21 at 1000 cycles in the obese group (mean, 0.203; 95% confidence interval [CI] 0.196-0.209) and at 6000 cycles in the insole group (mean, 0.200; 95% CI, 0.191-0.209). Although there was a significant time-dependent decrease in flexibility and energy absorption in both the obese and insole groups (P < 0.001), the difference between 1 and 10,000 cycles were significantly smaller in the insole group than in the obese group (P = 0.024).

CONCLUSIONS

Use of insoles for obese individuals may help to slow time-dependent foot structural changes. However, the effect was not enough to maintain the foot structure against repeated hyper loadings.

Kinematics and Laxity of the Ankle Joint in Anatomic and Nonanatomic Anterior Talofibular Ligament Repair: A Biomechanical Cadaveric Study

BACKGROUND

Although it is crucial to accurately identify the anterior talofibular ligament (ATFL) attachment site, it may not be feasible to fully observe the ATFL attachment site during arthroscopic surgery. As a result, the repair position might often be an unintentionally nonanatomic ATFL attachment site.

HYPOTHESIS

Anatomic ATFL repair restores kinematics and laxity to the ankle joint, while nonanatomic ATFL repair does not.

STUDY DESIGN

Controlled laboratory study.

METHODS

Seven normal fresh-frozen human cadaveric ankles were used. The ankles were tested with a 6 degrees of freedom robotic system. The following ankle states were evaluated: intact, ATFL injured, ATFL anatomic repair, and ATFL nonanatomic repair. The ATFL nonanatomic repair position was set 8 mm proximal from the center of the ATFL attachment site of the fibula. For each state, a passive plantarflexion (PF)-dorsiflexion (DF) kinematics test and a multidirectional loading test (anterior forces, inversion moment, and internal rotation moment) were performed.

RESULTS

The kinematics and laxity of the anatomic repair were not significantly different from those of the intact state. In nonanatomic repair, the inversion-eversion angle showed significant inversion (3.0°-3.4°) from 5° to 15° of DF, and the internal rotation-external rotation angle showed significant internal rotation (2.0°) at neutral PF-DF versus the intact state. In addition, internal rotation laxity was significantly increased (5.5°-5.8°) relative to the intact state in the nonanatomic repair at 30° and 15° of PF. There were no significant differences in anterior-posterior translation between the repairs.

CONCLUSION

Although the anatomic ATFL repair state did not show significant differences in kinematics and laxity relative to the intact state, the nonanatomic ATFL repair state demonstrated significant inversion and internal rotation kinematics and internal rotation laxity when compared with the intact state.

CLINICAL RELEVANCE

Nonanatomic repair alters kinematics and laxity from the intact condition.

Randomized clinical trial of single skin sterilization with a povidone-iodine applicator versus conventional skin sterilization in abdominal surgery

Background

The efficacy of widely used povidone–iodine applicators for skin sterilization in abdominal surgery is unclear. The aim of this trial was to evaluate whether sterilization with a povidone–iodine applicator was not inferior to a conventional sterilization method.

Methods

Patients undergoing elective abdominal surgery were assigned randomly to receive single sterilization with the applicator or conventional sterilization. The primary endpoint was wound infection rate. Secondary endpoints were rate of organ/space surgical‐site infection (SSI), adverse effects of povidone–iodine, amount of povidone–iodine used and total cost of sterilization.

Results

Of 498 patients eligible for the study between April 2015 and September 2017, 240 were assigned and analysed in the applicator group and 246 in the conventional group. Wound infection was detected in 16 patients (6·7 per cent) in the applicator group and 16 (6·5 per cent) in the conventional group (absolute difference 0·0016 (90 per cent c.i. −0·037 to 0·040) per cent; P = 0·014 for non‐inferiority). There was no difference between the groups in the organ/space SSI rate (11 patients (4·6 per cent) in the applicator group and 16 (6·5 per cent) in the conventional group. Both the amount of povidone–iodine used and the total cost of sterilization were higher in the conventional group than in the applicator group (median 76·7 versus 25 ml respectively, P < 0·001; median €7·0 versus €6·4, P < 0·001). Skin irritation was detected in three patients in the conventional group.

Conclusion

In abdominal surgery, this povidone–iodine applicator was not inferior to conventional sterilization in terms of the wound infection rate, and it is cheaper. Registration number: UMIN000018231 (http://www.umin.ac.jp/ctr/).

Talbot interferometry for imaging two-dimensional electron density distribution over discharge plasma with higher sensitivity

The basic properties of a Talbot interferometer implementing pinhole arrays were experimentally and numerically investigated for the improvement of measurement sensitivity of laser wavefront sensors utilized for electron density imaging over discharge plasmas. A numerical simulation using a plane wave decomposition method indicated that the pinhole arrays with a pitch of 300 μm and a pinhole diameter of 150 μm were most suitable for the measurement of the millimetre-scale discharge plasmas, in consideration of the spatial resolution and measurement accuracy. The plane wave decomposition simulation expected that the measurement sensitivity of the 8th-Talbot-length interferometer could be improved by a factor of 4 compared with the previously developed Shack-Hartmann type laser wavefront sensors, which was experimentally verified by the self-image behavior of the pinhole arrays. The Talbot interferometric system was successfully used for electron density imaging over the vacuum arcs generated between a 3-mm gap. The electron density image observed by the Talbot interferometers was in excellent agreement with that visualized by the previously developed Shack-Hartmann sensors. The practical notification for the pinhole array fabrication was also presented.

Investigation of factors related to the occurrence of osteochondral lesions of the talus by 3D bone morphology of the ankle

Aims

The aims of this study were to evaluate the morphology of the ankle in patients with an osteochondral lesion of the talus using 3D CT, and to investigate factors that predispose to this condition.

Patients and Methods

The study involved 19 patients (19 ankles) who underwent surgery for a medial osteochondral lesion (OLT group) and a control group of 19 healthy patients (19 ankles) without ankle pathology. The mean age was significantly lower in the OLT group than in the control group (27.0 vs 38.9 years; p = 0.02). There were 13 men and six women in each group. 3D CT models of the ankle were made based on Digital Imaging and Communications in Medicine (DICOM) data. The medial malleolar articular and tibial plafond surface, and the medial and lateral surface area of the trochlea of the talus were defined. The tibial axis-medial malleolus (TMM) angle, the medial malleolar surface area and volume (MMA and MMV) and the anterior opening angle of the talus were measured.

Results

The mean TMM angle was significantly larger in the OLT group (34.2°, sd 4.4°) than in the control group (29.2°, sd 4.8°; p = 0.002). The mean MMA and MMV were significantly smaller in the OLT group than in the control group (219.8 mm2, sd 42.4) vs (280.5 mm2, sd 38.2), and (2119.9 mm3, sd 562.5) vs (2646.4 mm3, sd 631.4; p < 0.01 and p = 0.01, respectively). The mean anterior opening angle of the talus was significantly larger in the OLT group than in the control group (15.4°, sd 3.9°) vs (10.2°, sd 3.6°; p < 0.001).

Conclusion

3D CT measurements showed that, in patients with a medial osteochondral lesion of the talus, the medial malleolus opens distally, the MMA and MMV are small, and the anterior opening angle of the talus is large. This suggests that abnormal morphology of the ankle predisposes to the development of osteochondral lesions of the talus. Cite this article: Bone Joint J 2018;100-B:1487–90.

Investigation of the Effect of Initial Graft Tension During Anterior Talofibular Ligament Reconstruction on Ankle Kinematics, Laxity, and In-situ Force

Category:

Basic Sciences/Biologics

Introduction/Purpose:

Ankle sprains are the most common sports injuries, and anterior talofibular ligament (ATFL) injury comprised 85% of all ankle sprains. Most patients recover with conservative treatment, but 20% of them progress to chronic ankle instability. Some studies have reported that anatomic reconstruction using a tendon graft is one of the best procedures to restore the ankle to its condition before symptom development. However, the effect of initial graft tension during ATFL reconstruction is still unclear. Therefore, the objective of this study was to investigate the effect of the initial graft tension during ATFL reconstruction.

Methods:

Eight fresh-frozen cadaveric ankle specimens were subjected to passive plantarflexion (PF)-dorsiflexion (DF) movement from 15° DF to 30° PF using the 6-degree-freedom robotic system. In addition, 60 N of anterior-posterior load, 1.7 Nm of inversion-eversion (IV-EV) torque, and 1.7 Nm of internal-external rotation (IR-ER) torque were applied to the ankle. During testing, 3-dimensional paths of the ankle were recorded simultaneously. Furthermore, in-situ forces of the ATFL and reconstructed graft were calculated using the principle of superposition. A repeated experiment was designed with the intact condition (intact), ATFL transection, and ATFL reconstruction with four different initial graft tensions (10 N, 30 N, 50 N, and 70 N).

Results:

AP laxity, IV-EV laxity and IR-ER laxity with ATFL transection was significantly greater than those with intact. In ATFL transection, the talus was significantly translated anteriorly with inversion and internal rotations under passive PF-DF motion compared with intact. Kinematic patterns and laxity in ATFL reconstruction with initial tension of 10 N and 30 N almost imitated intact, but in ATFL reconstruction with initial tension 70 N, the talus was significantly translated with external rotation compared with intact. As the initial graft tension during ATFL reconstruction increased, in-situ force of the reconstructed graft tended to increase during PF-DF motion. In-situ force of the reconstructed graft tension was significantly greater with initial tensions of 50 N, and 70 N than with intact during PF-DF motion (Figure 1).

Conclusion:

ATFL deficiency altered ankle kinematics and laxity. Although the optimal initial graft tension during ATFL reconstruction might restore ankle kinematics and laxity, excessive initial graft tension caused abnormal kinematics and laxity. Furthermore, the reconstructed graft tension increased as the initial tension increased. Initial tension during ATFL reconstruction has the important effect of imitating the normal ankle condition. We suggest that over-tensioning during ATFL reconstruction should be avoided in order to imitate the conditions of a normal ankle.

Factors Related to the Occurrence of Osteochondral Lesions of the Talus by 3-dimensional Bone Morphology of the Ankle

Category:

Ankle

Introduction/Purpose:

Repeated microtrauma is thought to play a major role in the occurrence of osteochondral lesions of the talus (OLTs), but much remains unknown. Two-dimensional assessments of the relationship between ankle bone morphology and OLTs are occasionally seen. The purpose of this study was to evaluate the bone morphology of the ankle in OLT 3-dimensionally using three-dimensional computed tomography (3DCT), and to investigate the factors related to the occurrence of OLTs.

Methods:

The subjects were 19 patients (19 ankles) who underwent surgery for medial OLTs (OLT group). They included 13 men and 6 women. A healthy group without ankle disease served as a control group with the same number of 19 ankles. Three-dimensional ankle joint models were made based on DICOM data obtained with CT images. In the 3D model, the medial malleolus articular surface and the tibial plafond surface, the medial surface of the trochlea of the talus, and the lateral surface of the trochlea of the talus were defined. The tibial axis-medial malleolus (TMM) angle, the medial malleolus surface area (MMA), the medial malleolus volume (MMV), and the anterior opening angle of the talus were measured 3-dimensionally and compared in the OLT and control groups.

Results:

The mean TMM angle was significantly larger in the OLT group (34.2 ± 4.4°) than in the control group (29.2 ± 4.8°; p = 0.002). The mean MMA was significantly smaller in the OLT group (219.8 ± 42.4 mm2) than in the control group (280.5 ± 38.2 mm2; p < 0.001). The mean MMV was significantly smaller in the OLT group (2119.9 ± 562.5 mm3) than in the control group (2646.4 ± 631.4 mm3; p = 0.01). The mean anterior opening angle of the talus was significantly larger in the OLT group (15.4 ± 3.9°) than in the control group (10.2 ± 3.6°; p < 0.001).

Conclusion:

It was shown with 3DCT measurements that, in medial OLT patients, the medial malleolus opens distally, the MMA and MMV are small, and the talus anterior opening angle was significantly larger than in controls. This study suggests the possibility that the 3D bone morphology of both the mortise and tenon of the ankle joint are closely related to the occurrence of OLTs.

Stability of the ankle joint in anatomical or non-anatomical anterior talofibular ligament repair

Category:

Ankle

Introduction/Purpose:

Chronic ankle instability (CAI) often needs surgical treatment if conservative treatment is ineffective. Recently, arthroscopic surgeries have become widely used to treat CAI. Although it is crucial to accurately ascertain the anterior talofibular ligament (ATFL) attachment site under arthroscopy, previous study showed that it might not be feasible to thoroughly observe the ATFL attachment site, and repair or reconstruction position were often unintentionally carried out proximal to the ATFL attachment site at the fibula as a result. Currently, there are few reports about stability of the ankle joint by different repair position of ATFL. The aim of this study was to evaluate the stability of the ankle joint by different repair position of ATFL.

Methods:

Six fresh-frozen human cadaveric ankles with the mean age of 83.5 ± 7.3 years were used. The ankles were tested using a six-degrees of freedom robotic system. The following ankle states were evaluated: intact, ATFL transection, ATFL anatomical repair, and ATFL non-anatomical repair. ATFL was transected at fibular attachment. Anatomical repair was performed at the center of original ATFL attachment of the fibula. Non-anatomical repair was set 8mm proximal from anatomical ATFL attachment of the fibula. At each state, laxity of anterior translation under 60 N load, inversion under 1.7 Nm load, and internal rotation under 1.7 Nm load were evaluated. Each test was performed at 30 degrees plantarflexion (PF), 15 degrees PF, 0 degree, and 15 degrees dorsiflexion (DF). The one-way repeated measures analysis of variance (ANOVA) with post hoc pairwise comparisons with Dunnett’s test was adopted. A P value of 0.05 was chosen as the level of significance.

Results:

Anterior translation under 60 N load was significantly increased in transection condition at 30 degrees PF compared with the intact condition (P=0.005). Anatomical repair and Non-anatomical repair did not show significant differences. Inversion under 1.7 Nm load was significantly increased in transection condition at 30 and 15 degrees PF compared with the intact condition (P=0.004, =0.049). Anatomical repair and Non-anatomical repair did not show significant differences. Internal rotation under 1.7 Nm load was significantly increased in transection condition at 30, 15 degrees PF and 0 degree compared with the intact condition (P<0.001, <0.001, and <0.001). Although anatomical repair did not show significant differences, non-anatomical repair showed significant increase at 30 and 15 degrees compared with the intact condition (P=0.006, =0.026). (Fig. 1).

Conclusion:

Anatomical repair did not show significant difference in all three loads with the intact condition. In non-anatomical repair, anterior translation and inversion did not show significant difference, but internal rotation significantly increased at 30 and 15 degrees PF compared with the intact condition. Compared with anatomical repair, non-anatomical repair might become more vertical ligament running because its attachment site of the fibula was more proximal. This difference might affect stability of the ankle joint. Anatomical repair of the ATFL might be essential to obtain the stability of the ankle joint like the intact condition.

Congenital Combined Deficiency of Factor V and Factor VIII

A case of congenital combined deficiency of factor V and factor VIII was reported. The patient, a 9 year old boy, gave a history of epistaxis, hematomas, and of hemorrhages following dental extraction since the age of 2 ; plasma levels of factor V and factor VIII were found to be 16% and 8% of normal, respectively. No one in his family had a deficiency of either factor. The effects of transfusion of normal fresh plasma and whole blood from a patient with hemophilia A were studied. While the former were similar to the pattern as seen in classical hemophilia, the latter consisted of an immediate increase of factor V activity and a delayed increase of factor VIII activity, despite the fact that factor VIII activity was almost absent from the donor’s blood.

Tibiotalocalcaneal Arthrodesis Using a Soft Tissue-Preserved Fibular Graft for Treatment of Large Bone Defects in the Ankle

BACKGROUND

Pathogenesis of ankle disorders with a large bone defect is varied and treatment for those problems is challenging for orthopaedic surgeons. The aims of this study were to present an operative technique of arthrodesis for the reconstruction of the ankle and hindfoot with a large bone defect using a soft tissue-preserved fibular strut graft and to report outcomes of consecutively treated patients.

METHODS

Twelve feet from 11 patients, including feet with aseptic necrosis of the talus and total ankle implant loosening, were treated. Bone defects were filled using iliac bone and/or resected fibula and tibiotalocalcaneal arthrodesis was performed using a retrograde intramedullary nail. A modified transfibular approach was used to expose the affected joint while preserving the lateral to posterior skin and soft tissues on the fibula. The periods of bony fusion and outcomes were radiographically and clinically evaluated. The mean follow-up period was 33.4 months.

RESULTS

Bony fusion was achieved within 3 months in all cases. Coronal and sagittal alignments were acceptable, and the mean American Orthopaedic Foot & Ankle Score improved from 53.8 to 75.5 at the final follow-up. All patients graded their results of treatment as "satisfied."

CONCLUSION

This procedure did not require special techniques and it should be applicable to complicated cases with large bone defects. High fusion rates that we believe are due to preserving blood supply to the fibular graft can be expected with preservation of the hindfoot height.

LEVEL OF EVIDENCE

Level IV, case series.

Repair of Acute Patellar Tendon Rupture Augmented with Strong Sutures

Rupture of the patellar tendon is an uncommon injury that requires acute surgical repair to restore the function of the knee. Multiple techniques for repair have been described in the literature. Complications with these repair techniques include rerupture and extensor lag caused by gap formation at the site of repair. Thus, many surgeons have suggested augmenting the standard repair. Several methods of augmentation have been described each with disadvantages. The purpose of this article was to present our case series of six patients with acute patella tendon ruptures treated by a novel procedure using strong sutures. In this method, eight strands of four-strong sutures run within the tendon. At the patellar site, a combination of suture button and figure eight pattern techniques is used, avoiding stress concentration. The optimal tension is applied to each suture, so as the patella might be positioned at the original placement. Then all sutures are secured onto the tibia. Postoperatively with a mean follow-up of 32.7 months (range: 25-48 months), all patients had a stable knee with mean flexion of 143.3 degrees (range: 140-150 degrees) and without any extension lag. With an improvement in the International Knee Documentation Committee score to 86.8 (range: 80-92), the excellent outcome was noted in all patients. The average postoperative Lysholm score was 98.8 (range: 97-100) and the average Kujala score was 95.2 (range: 92-97). All patients recovered to near-normal strength and stability of the patellar tendon as well as restoration of function after the operation. This augmentation technique offers a distinct advantage over previous augmentation methods and materials, and may be especially useful in managing patellar tendon rupture caused by rheumatoid arthritis or other systemic conditions. For these reasons, we recommend this procedure for acute patellar tendon ruptures.

Early results of multicenter phase II trial of perioperative oxaliplatin and capecitabine without radiotherapy for high-risk rectal cancer: CORONA I study

BACKGROUNDS

Perioperative introduction of developed chemotherapy into the treatment strategy for locally advanced rectal cancer (LARC) may be a promising option. However, the most prevalent treatment for high-risk LARC remains preoperative chemoradiotherapy (CRT) in Western countries.

PATIENTS AND METHODS

A phase II trial was undertaken to evaluate safety and efficacy of perioperative XELOX without radiotherapy (RT) for patients with high-risk LARC. Patients received 4 cycles of XELOX before and after surgery, respectively. Primary endpoint was disease-free survival.

RESULTS

We enrolled 41 patients between June 2012 and April 2014. The completion rate of the preoperative XELOX was 90.3%. Twenty-nine patients (70.7%) could start postoperative XELOX, 15 of these patients (51.7%) completed 4 cycles. Allergic reaction to oxaliplatin was experienced by 5 patients (17.2%) during postoperative XELOX. One patient received additional RT after preoperative XELOX. Consequently, the remaining 40 patients underwent primary resection. Major complications occurred in 6 of 40 patients (15.0%). Pathological complete response (pCR) rate was 12.2%, and good tumor regression was exhibited in 31.7%. N down-staging (cN+ to ypN0) and T down-staging were detected in 56.7% and 52.5%, respectively. Clinical T4 tumor was a predictor of poor pathological response (p < 0.001).

CONCLUSIONS

We could show the favorable pCR rate after preoperative XELOX alone. However, the T and N down-staging rate was likely to be insufficient. When tumor regression is essential for curative resection, the use of preoperative CRT is likely to be recommended. For patients with massive LN metastasis, the additional Bev to NAC might be a promising option.