Technical note: Anterior cruciate ligament reconstruction in the presence of an intramedullary femoral nail using anteromedial drilling

AIM To describe an approach to anterior cruciate ligament(ACL) reconstruction using autologous hamstring by drilling via the anteromedial portal in the presence of an intramedullary(IM) femoral nail.METHODS Once preoperative imagining has characterized the proposed location of the femoral tunnel preparations are made to remove all of the hardware(locking bolts and IM nail). A diagnostic arthroscopy is performed in the usual fashion addressing all intra-articular pathology. The ACL remnant and lateral wall soft tissues are removed from the intercondylar, to provide adequate visualization of the ACL footprint. Femoral tunnel placement is performed using a transportal ACL guide with desired offset and the knee flexed to 2.09 rad. The Beath pin is placed through the guide starting at the ACL's anatomic footprint using arthroscopic visualization and/or fluoroscopic guidance. If resistance is met while placing the Beath pin, the arthroscopy should be discontinued and the obstructing hardware should be removed under fluoroscopic guidance. When the Beath pin is successfully placed through the lateral femur, it is overdrilled with a 4.5 mm Endobutton drill. If the Endobutton drill is obstructed, the obstructing hardware should be removed under fluoroscopic guidance. In this case, the obstruction is more likely during Endobutton drilling due to its larger diameter and increased rigidity compared to the Beath pin. The femoral tunnel is then drilled using a best approximation of the graft's outer diameter. We recommend at least 7 mm diameter to minimize the risk of graft failure. Autologous hamstring grafts are generally between 6.8 and 8.6 mm in diameter. After reaming, the knee is flexed to 1.57 rad, the arthroscope placed through the anteromedial portal to confirm the femoral tunnel position, referencing the posterior wall and lateral cortex. For a quadrupled hamstring graft, the gracilis and semitendinosus tendons are then harvested in the standard fashion. The tendons are whip stitched, quadrupled and shaped to match the diameter of the prepared femoral tunnel. If the diameter of the patient's autologous hamstring graft is insufficient to fill the prepared femoral tunnel, the autograft may be supplemented with an allograft. The remainder of the reconstruction is performed according to surgeon preference. RESULTS The presence of retained hardware presents a challenge for surgeons treating patients with knee instability. In cruciate ligament reconstruction, distal femoral and proximal tibial implants hardware may confound tunnel placement, making removal of hardware necessary, unless techniques are adopted to allow for anatomic placement of the graft. CONCLUSION This report demonstrates how the femoral tunnel can be created using the anteromedial portal instead of a transtibial approach for reconstruction of the ACL.

Internal fixation and unicompartmental knee arthroplasty for an elderly patient with patellar fracture and anteromedial osteoarthritis:A case report

BACKGROUND Open reduction and internal fixation(ORIF)is the traditional surgical treatment for patellar fractures,and unicompartmental knee arthroplasty(UKA),especially Oxford UKA,has been increasingly used in patients with medial knee osteoarthritis(OA).However,the process of choosing treatment for patients with both patellar fractures and anteromedial knee OA remains unclear.We present the case of a patient with a patellar fracture and anteromedial OA.CASE SUMMARY We present the case of a 72-year-old woman with a history of bilateral medial compartment OA of the knees and a right Oxford UKA.She also experienced a recent left patellar fracture.ORIF and Oxford UKA were performed in a single stage.The patient showed excellent postoperative clinical results.CONCLUSION ORIF and Oxford UKA can be performed simultaneously for patients with patellar fracture and anteromedial OA on the same knee.

Anteromedial Plating of Humerus—An Easier and Effective Approach

Plate osteosynthesis of humeral shaft fractures is an established surgical procedure. Iatrogenic radial nerve palsy appears to be common complication in treating these fractures. A case series of 20 fracture shafts of humerus were treated with anteromedial plating through anterolateral approach. There was no radial nerve palsy in any of the cases and all achieved fracture union.

Irreducible anteromedial radial head dislocation without fracture caused by transposed biceps tendon in an adult:A case report and literature review

Irreducible anteromedial radial head dislocation(IARHD)caused by transposed biceps tendon is rare.Delayed diagnosis and surgical failure often occur.A 46-year-old fisherman presented with 10 days history of painful swelling and restricted movement of his right elbow due to strangulation injury by a fishing boat cable.On examination,the images of the right elbow reveals in a"semi-extended and pronated"elastic fixation position.Radiography and 3-dimensional reconstruction CT reveals an isolated anteromedial radial head dislocation with extreme protonation of the radius and the bicipital tuberosity towards the posterior aspect of the elbow joint,and MRI shows biceps tendon wrapping around the radial neck,similar to umbilical cord wrapping seen in newborns.The Henry approach was applied for the first time to reduce the biceps tendon.The patient achieved a good functional recovery at 26 months,which represents the first reported case of IARHD without fracture caused by biceps tendon in an adult.In treatment of IARHD,attention should be paid to the phenomenon of biceps tendon transposition.Careful clinical examination,comprehensive imaging modalities,and appropriate surgical approach are the keys to successful management.

Outcome of posterior wall blowout in anterior cruciate ligament (ACL) reconstruction via anteromedial portal approach: A retrospective research in 20 patients with 6 years follow-up

Purpose: To evaluate the clinical outcome in patients who received anterior cruciate ligament (ACL) rec on structi on via an teromedial portal with or without posterior wall blowout. Methods: Twenty patients w让h ruptured ACL, who have received ACL reconstruction via anteromedial portal between Apr 2012 and Oct 2013 were enrolled. According to the conditions of posterior wall, the patients were divided into 2 groups: posterior wall blowout group (10 patients) and posterior wall intact group (10 patients). The median follow up time were 63 (range 19-75) months and 60.5 (range 25—64) months in the 2 groups respectively. The clinical outcome was evaluated by knee joint physical examinati on, mag netic resonance imaging (MRI), the Inter national Knee Docume ntation Comm 让 tee (IKDC) 2000 subjective score, Lysholm score. Ten ger score, difference of thigh circumfere nee, KT-2000 and Biodex isokinetic dynamometer system. Results: No significant differences were found in terms of the IKDC score, Lysholm score, Tegner score, Lachman test positive rate or Pivot Shift test positive rate between the two groups. In KT-2000 and Biodex isokinetic dynamometer tests, the differenee of muscle strength between affected knees and unaffected knees in posterior wall blowout group was not significant less than that of posterior wall intact group (p > 0.05). In addition, there is no statistical difference between the two groups in signal/ noise quotient (SNQ) of the graft (p > 0.05) in post operative MRI. Conclusion: Blowout of posterior wall in ACL reconstruction via anteromedial portal does not affect the clinical outcome as long as reliable fixation has been taken intraoperatively.

Biomechanical Study of the Fixation Strength of Anteromedial Plating for Humeral Shaft Fractures

Background： Open reduction and internal fixation with plate and screws are the gold standard for the surgical treatment of humeral shaft fractures, this study was to compare the mechanical properties ofanteromedial, anterolateral, and posterior plating for humeral shaft fractures. Methods： A distal third humeral shaft fracture model was constructed using fourth-generation sawbones （#3404, composite bone）. A total of 24 sawbones with a distal third humeral shaft fracture was randomly divided into three Groups： A, B, and C （n = 8 in each group） for anteromedial, anterolateral, and posterior plating, respectively. All sawbones were subjected to horizontal torsional fatigue tests, horizontal torsional and axial compressive fatigue tests, four-point bending fatigue tests in anteroposterior （AP） and mediolateral （ML） directions and horizontal torsional destructive tests. Results： In the horizontal torsional fatigue tests, the mean torsional angle amplitude in Groups A, B, and C were 6.12°, 6.53°, and 6.81°. In horizontal torsional and axial compressive fatigue tests, the mean torsional angle amplitude in Groups A, B, and C were 5.66°, 5.67°, and 6.36°. The mean plate displacement amplitude was 0.05 mm, 0.08 mm, and 0.10 mm. Group A was smaller than Group C （P 〈 0.05）. In AP four-point bending fatigue tests, the mean plate displacement amplitude was 0.16 ram, 0.13 ram, and 0.20 mm. Group B was smaller than Group C （P 〈 0.05）. In ML lbur-point bending fatigue tests, the mean plate displacement amplitude were 0.16 mm, 0.19 ram, and 0.17 ram. In horizontal torsional destructive tests, the mean torsional rigidity in Groups A, B, and C was 0.82, 0.75, and 0.76 N·m/deg. The yielding torsional angle was 24.50°, 25.70°, and 23.86°. The mean yielding torque was 18.46, 18.05. and 16.83 N·m, respectively. Conclusions： Anteromedial plating was superior to anterolateral or posterior plating in all mechanical tests except in AP four-point bending fatigue tests compared to the anterolateral plating group. We can suggest that anteromedial plating is a clinically safe and effective way for humeral shaft fractures.

Regulation of Cued Fear Expression via Corticotropin-ReleasingFactor Neurons in the Ventral Anteromedial Thalamic Nucleus

The ventral part of the anteromedial thalamic nucleus(AMv)is in a position to convey information to the cortico-hippocampal-amygdalar circuit involved in the processing of fear memory.Corticotropin-releasing-factor(CRF)neurons are closely associated with the regulation of stress and fear.However,few studies have focused on the role of thalamic CRF neurons in fear memory.In the present study,using a conditioned fear paradigm in CRF transgenic mice,we found that the c-Fos protein in the AMv CRF neurons was significantly increased after cued fear expression.Chemogenetic activation of AMv CRF neurons enhanced cued fear expression,whereas inhibition had the opposite effect on the cued fear response.Moreover,chemogenetic manipulation of AMv CRF neurons did not affect fear acquisition or contextual fear expression.In addition,anterograde tracing of projections revealed that AMv CRF neurons project to wide areas of the cerebral cortex and the limbic system.These results uncover a critical role of AMv CRF neurons in the regulation of conditioned fear memory.

Redislocation Following Zigzag Osteotomy Combined with Fibular Allograt for Dislocation of the Hip in Children

We have reviewed 17 patients (18 hips) who required repeated open reduction for recurrent or persistent dislocation after a previous attempt at zigzag osteotomy combined with fibular allowgraft for developmental dysplasia of the hip (DDH). The purposes of this study were to examine predictors of redislocation and to evaluate the long-term outcomes after revision surgery. The mean age at primary open reduction was 24 months (13 to 36). The median time to the recognition of failure was 4.6 months. The second reduction was performed at a mean age of 26.3 months (17 to 42) and the mean age at final follow-up was 79.7 months (58 to 105) and the mean time follow-up was 42.4 months (37 to 76). We treated the hips with a new open reduction through an anteromedial approach. A constricted anteromedial capsule was always found as the main factor;all had an intact anteromedial capsule, and there was an inverted transverse ligament in five cases and a very tight psoas tendon in another four cases, eversion of the limbus in six cases, densing anterior capsule in five cases. We perform with the condition that all hips were cleared of scar tissue;five hips had adductor tenotomy;four hips required release of the psoas tendon, five eversion of the limbus. Release of the transverse ligament was required in five cases each. All hips with Kirschner wire through the femoral head into the acetabulum. Three hips required femoral shortening (average of 1.5 cm);a derotation varus osteotomy was performed in two hips from ten and twelve weeks after repeated open reduction. Postoperative results according to modified McKay criteria for clinical: excellent: 3 of 18 hips (16.7%);good: 8 of 18 hips (44.4%);fair: 6 of 18 hips (33.3%);and poor: 1 of 18 hips (5.6%). We suggest that technical failure is usually the cause for redislocation with all that has an intact anteromedial capsule. There was an inverted transverse ligament, tight psoas tendon, eversion of the limbus, and densing anterior capsule. We believe that abnormal femoral version and femoral head dysplasia are also important factors for redislocation too.

Buttress plate fixation of coronoid process fractures via a medial approach

Purpose:To assess the clinical and radiographic outcomes of coronoid process fractures surgically managed with buttress plate fixation via a medial approach.Methods:A retrospective review of all coronoid fractures surgically fixed in our institution using a buttress plate technique via a medial approach between June 2012 and April 2015 by the senior author was performed.These fractures were all sizeable fractures contributing to persistent elbow instability in terrible triad or varus posteromedial rotatory instability injury patterns.A prospective telephone questionnaire was conducted to assess patient outcomes using the disabilities of the arm,shoulder and hand(DASH)score and Mayo hlbow performance score(MEPS).Results:Twelve patients were included in the study,comprising 10 males and 2 females with an average age of 39 years(range,19-72 years).Mean follow-up was 16 months(range.4-18 months).The average time to radiographic union was 4 months(range.3-7 months).Range of motion measurements at final follow-up were obtained in 11 out of 12 patients,with one patient defaulting follow-up.All 11 patients displayed a functional elbow range of motion of at least 30°-130°.with an average arc of motion of 130°(range.110°-140°).mean elbow flexion of 134°(range.110°-140°)and mean flexion contracture of 3°(range.0°-20°).The mean DASH score was 16(range.2.5-43.8)and the mean MEPS was 75(range.65-100).Complications observed included one patient with a superfic ial wound infection which resolved with a course of oral antibiotics and one patient with radiographic evidence of heterotopic ossification which was conservatively managed.No residual elbow instability was observed and no reoperations were performed.Conclusion:Buttress plate fixation via a medial approach of coronoid process fractures that contribute to persistent elbow instability represents a reliable method of treatment that produces satisfactory and predictable outcomes.