Modified Langenskiöld Procedure for Congenital Patella Dislocations in Pediatric Patients

Background: Great difficulty and more failures were the descriptions of the treatment of congenital patella dislocation in pediatric patients. This study aims to evaluate the outcomes of patients with congenital patellar dislocations treated with the modified Langenskiöld procedure. Methods: The medical records of 16 knees in 11 patients with a diagnosis of congenital patella dislocation were collected from September 2016 to March 2019. They were treated with the modified Langenskiöld procedure. The mean follow-up period was 37.8 months. The outcome measures were the Lysholm score, Kujala score, patellar stability, and knee range of motion. Results: Eleven patients, namely, eight girls and three boys, with 16 knees were enrolled. The mean age at the time of operation was 3.1 years. The post-operative mean Lysholm score was 94.8 (SD 5.1; 87–100), whereas the Kujala score was 95 (SD 5.9; 86–100). There were no recurrent dislocations, and all patients had full extension postoperatively. Conclusion: The modified Langenskiöld procedure is a promising solution for the treatment of congenital patella dislocations. Level of evidence: Level IV; Case Series; Treatment Study

Effect of the Knee and Hip Angles on Knee Extensor Torque: Neural, Architectural, and Mechanical Considerations

This study examined the influence of knee extensors’ hip and knee angle on force production capacity and their neuromuscular and architectural consequences. Sixteen healthy men performed sub-maximal and maximal voluntary isometric contractions (MVIC) of knee extensors with four different combinations of the knee and hip angles. Muscle architecture, excitation-contraction coupling process, muscular activity, and corticospinal excitability were evaluated on the vastus lateralis (VL) and rectus femoris (RF) muscles. MVIC and evoked peak twitch (Pt) torques of knee extensors increased significantly (p < 0.05) by 42 ± 12% and 47 ± 16% on average, respectively, under knee flexed positions (110° flexion, 0° = full extension) compared to knee extended positions (20° flexion) but were not different between hip positions (i.e., 0° or 60° flexion). Knee flexion also affected VL and RF muscle and fascicle lengths toward greater length than under knee extended position, while pennation angle decreased for both muscles with knee flexion. Pennation angles of the VL muscle were also lower under extended hip positions. Alternatively, no change in maximal muscle activation or corticospinal activity occurred for the VL and RF muscles across the different positions. Altogether these findings evidenced that MVIC torque of knee extensors depended particularly upon peripheral contractile elements, such as VL and RF muscle and fascicle lengths, but was unaffected by central factors (i.e., muscle activation). Furthermore, the hip position can affect the pennation angle of the VL, while VL muscle length can affect the pennation angle of the RF muscle. These elements suggest that the VL and RF muscles exert a mutual influence on their architecture, probably related to the rectus-vastus aponeurosis.

Outcome of rest with or without bandaging for treatment of carpal flexural contracture deformities in puppies: 47 puppies and 75 joints (2000–2018)

OBJECTIVE To review outcome of dogs with carpal flexural contracture deformities treated with rest alone or with rest and bandaging. ANIMALS 47 dogs (75 joints). PROCEDURES Medical records of dogs with unilateral or bilateral carpal flexural contracture deformities were reviewed, and dogs were grouped according to deformity severity grade (graded on a scale from 1 to 3) at the time of diagnosis. Two treatment groups were compared: rest only and rest with a modified Robert-Jones bandage. All dogs were reevaluated weekly until recovery (ie, resolution of the deformity and lameness). RESULTS All dogs responded to conservative management, with all dogs regaining full extension of the antebrachiocarpal joint and ambulating normally at the time of the final visit. Mean ± SD time from initial diagnosis to recovery (ie, resolution of the deformity and lameness) was 2.9 ± 2.2 weeks (median, 2 weeks; range, 1 to 9 weeks). For dogs with grade 1 or 2 severity, mean time to recovery did not differ significantly between treatment groups. For dogs with grade 3 severity, however, mean time to recovery was significantly shorter for dogs treated with rest and bandaging than for dogs treated with rest alone. CLINICAL RELEVANCE Results suggested that conservative management (rest alone or rest and bandaging) was a successful treatment option for puppies with carpal flexural contracture deformity and that bandaging resulted in a shorter time to recovery for dogs that were severely affected.

A Novel Clinical-Driven Design for Robotic Hand Rehabilitation: Combining Sensory Training, Effortless Setup, and Large Range of Motion in a Palmar Device

Neurorehabilitation research suggests that not only high training intensity, but also somatosensory information plays a fundamental role in the recovery of stroke patients. Yet, there is currently a lack of easy-to-use robotic solutions for sensorimotor hand rehabilitation. We addressed this shortcoming by developing a novel clinical-driven robotic hand rehabilitation device, which is capable of fine haptic rendering, and that supports physiological full flexion/extension of the fingers while offering an effortless setup. Our palmar design, based on a parallelogram coupled to a principal revolute joint, introduces the following novelties: (1) While allowing for an effortless installation of the user's hand, it offers large range of motion of the fingers (full extension to 180° flexion). (2) The kinematic design ensures that all fingers are supported through the full range of motion and that the little finger does not lose contact with the finger support in extension. (3) We took into consideration that a handle is usually comfortably grasped such that its longitudinal axis runs obliquely from the metacarpophalangeal joint of the index finger to the base of the hypothenar eminence. (4) The fingertip path was optimized to guarantee physiologically correct finger movements for a large variety of hand sizes. Moreover, the device possesses a high mechanical transparency, which was achieved using a backdrivable cable transmission. The transparency was further improved with the implementation of friction and gravity compensation. In a test with six healthy participants, the root mean square of the human-robot interaction force was found to remain as low as 1.37 N in a dynamic task. With its clinical-driven design and easy-to-use setup, our robotic device for hand sensorimotor rehabilitation has the potential for high clinical acceptance, applicability and effectiveness.

Correlation between Morphological Features of the Anterior Cruciate Ligament: A Quantitative Study Using a Porcine Model

Background: Inadequate restoration of the rotational knee stability is often reported after ACL reconstruction, mainly due to insufficient restoration of the morphology of the ACL. This study aimed to explore the quantitative correlation between morphological features of the ACL, thus to provide useful information for improving anatomical reconstruction techniques and designing artificial ligaments. Methods: Porcine model was used in this study mainly because the morphology and function of porcine ACLs have been reported to be similar to those of the human ACL. 19 porcine knees (1 year, male) were fixed at full extension using 10% formalin and were dissected to expose the ACL. ACL lengths were measured using a caliper. Mid-substances of the ACL were cut and scanned using X-ray microscopy, and the cross-sectional area (CSA) was measured at the isthmus. Margins of direct and indirect bone insertion sites were distinguished and marked. Measurements were performed on digital photographs to obtain the areas of bone insertions. Statistical analysis using nonlinear regression was used to identify potential correlations among the measurements. Results: The results showed large individual differences on all of the measurements (e.g. the CSA at ACL isthmus ranged from 44.7 to 87.2 mm2, when the area of its femoral and tibial insertion sites ranged from 188.1 and 233.6 mm2 to 258.4 and 412.0 mm2, respectively). The CSA at the isthmus was significantly correlated with the total area of the bone insertion sites and the area of tibial insertion. The area of the tibial insertion was significantly correlated with the area of its direct insertion site. In contrast, the area of the femoral insertion was significantly correlated with the area of its indirect insertion site. The area of the indirect tibial insertion showed a weak correlation with the length of ACL, whereas the length of the ACL was not able to predict or be predicted by any other parameters.Conclusions: The CSA at the ACL isthmus might be more suitable for assessing the morphology of the ACL. However, ACL length has little correlation with the CSA of the isthmus or bone insertion sites, thus should be evaluated independently before surgery.

miR-409-3p represses Cited2 at the evolutionary emergence of the callosal and corticospinal projections

Callosal projection neurons are a broad population of interhemispheric projection neurons that extend an axon across the corpus callosum to connect the two cerebral hemispheres. The corticospinal tract, comprised of the axons of corticospinal projection neurons, is unique to mammals, and its full extension to the lumbar segments that control walking is, like the corpus callosum, unique to placental mammals. The emergence of these two distinct axonal tracts is thought to underpin the evolutionary expansion of complex motor and cognitive abilities. The molecular mechanisms regulating the divergence of corticospinal and callosal projection neurons are incompletely understood. Our recent work identifies a genomic cluster of microRNAs (12qF1/Mirg) unique to placental mammals. These clustered miRNAs are specifically expressed by corticospinal vs. callosal projection neurons during the molecular refinement of corticospinal vs. callosal projection neuron fate (1). One of these, miR-409-3p, can convert layer V callosal into corticospinal projection neurons, acting in part through repression of the callosal-expressed transcriptional regulator Lmo4. This conversion is partial, however, suggesting that miR-409-3p represses multiple callosal projection neuron control genes in order to specify corticospinal projection neurons. One potential additional target of miR-409-3p repression is the callosal-expressed transcriptional co-activator Cited2. Cited2 interacts genetically with Lmo4, and Lmo4 can partially functionally compensate for Cited2 in thymus development(2). Further, Cited2 and Lmo4 function as opposing molecular controls over specific areal identity within superficial layer callosal projection neurons of the somatosensory and motor cortices, respectively (3). Cited2 is highly expressed by callosal, relative to corticospinal, projection neurons from the earliest stages of neurogenesis. Cited2 is necessary for the expansion of intermediate progenitor cells (IPCs) in the subventricular zone (SVZ), and the resulting generation of superficial layer callosal projection neurons. Here we show that miR-409-3p and Cited2 interact in IPCs and in corticospinal vs. deep layer callosal projection neuron development. miR-409-3p represses the Cited2 3UTR in luciferase assays. Mirg, which encodes miR-409-3p, and Cited2, are reciprocally expressed in IPCs at e15.5 by qPCR. Furthermore, miR-409-3p gain-of-function results in a phenocopy of established Cited2 loss-of-function in IPCs. Later on, miR-409-3p and Cited2 exert opposing effects on the adoption of corticospinal vs. callosal projection neuron subtype identity. Taken together, our work suggests that miR-409-3p, and possibly other 12qF1 miRNAs, represses Cited2 in IPCs to limit their proliferation, and in developing corticospinal and deep layer callosal projection neurons to favor corticospinal fate.

Lateral Patellofemoral Ligament Reconstruction With a Hamstring Allograft

Background: Medial patellar instability is rare but may occur after lateral retinacular release. The lateral patellofemoral ligament is a significant stabilizer for medial and lateral patellar displacement, and soft tissue–based reconstruction may restore its stabilizing effect. Indications: Lateral patellofemoral ligament reconstruction (LPFLR) is indicated for patellar instability failing exhaustive nonoperative measures. Technique Description: Diagnostic arthroscopy for medial patellofemoral ligament (MPFL) status, patellar tracking, chondral status, and postoperative changes of lateral retinacular release is conducted. A 5-cm incision is made between the midpoint of the patella and the lateral epicondyle, or a single midline incision can be used if performing a concomitant MPFL reconstruction. Dissection is carried down to the lateral retinaculum and capsule, and two 1-cm incisions are made at the distal and proximal patella through the patellar and quadriceps tendon, respectively. The lateral epicondyle is then directly palpated, and two 1-cm incisions are made directly anterior and posterior to the epicondyle into the iliotibial band in full extension. A hamstring allograft is then shuttled in a V-shaped configuration from the quadriceps tendon through the iliotibial band and finally to the patellar tendon. Excess graft is trimmed and doubled over proximally and distally to replicate the normal (or contralateral) 0° to 15° of patellar eversion. Trial resting length and tension is set with temporary sutures through the proximal and distal doubled graft in full extension. The knee is taken through full range of motion to ensure there is no graft tightening in flexion or loosening in full extension. Eversion and patellar translation are then examined. Heavy nonabsorbable sutures are used to set length of the doubled allograft proximally and distally. Results: Case series of LPFLR have demonstrated significant improvements in patients’ pain, Lysholm score and Knee Injury and Osteoarthritis Outcome Score, and kinesiophobia with no instability events and normal range of motion at short-term follow-up. Discussion/Conclusion: Medial patellar instability can occur following lateral retinacular release and patients experiencing instability despite nonoperative treatment are likely to benefit from a soft tissue–based LPFLR. Although other nongraft-based techniques may confer similar outcomes, the authors find it more reliable to perform a lateral reconstruction as described.

Arthroscopic Medial Meniscus Root Repair With Transtibial Ripstop Technique

Background: Meniscal root tears are radial tears occurring at or within 1 cm of the meniscal root attachment. These injuries have been shown to be the biomechanical equivalent of a total meniscectomy and are thought to be responsible for a rapid progression of osteoarthritis if left untreated. Indications: Meniscal root repair is indicated if possible, with the exception of patients who have diffuse Outerbridge 3-4 osteoarthritis of the ipsilateral compartment, those who are poor surgical candidates due to age or medical comorbidity, or in whom nonsymptomatic tears are found incidentally. Technique Description: Standard 2-portal arthroscopy is performed. Once a medial root tear has been identified and concomitant pathology has been addressed, we typically begin the repair by trephinating the deep medial collateral ligament with an 18-gauge needle to enhance visualization and avoid iatrogenic cartilage injury. Arthroscopic shaver is used to debride the meniscal root as needed. A meniscal root guide is introduced into the joint and an incision is made on the anteromedial tibia for outside-in drilling of a transosseous tunnel. Drilling is performed with a 5-mm retroreaming device, and a 10-mm socket is created. Nonabsorbable suture is then passed through the meniscus using a self-capture device in an inverted mattress configuration, following by 2 cinch stitches. The sutures are then shuttled into the transosseous tunnel, and the meniscal root is reduced and tensioned in full extension, with the sutures being fixated into a suture anchor on the anteromedial tibia. Results: A recent large systematic review of 1086 patients undergoing treatment of meniscal root tear via either debridement or nonoperative management compared with meniscal repair found that conversion to total knee arthroplasty occurred in 11% to 54% of those managed via debridement or nonoperative care versus 0% to 1% for those with root repair. Discussion/Conclusion: Currently, meniscal root repair offers the greatest improvement and lowest risk of conversion to arthroplasty following meniscal root tear. The present technique offers a durable repair that we believe combines ease of execution with decreased risk of suture pull-out, by creating a ripstop-type construct. Long-term outcome studies are needed for this and other root repair techniques.

CONSERVATIVE REHABILITATION OF PARTIAL ANTERIOR CRUCIATE LIGAMENT TEAR FOR BETTER FUNCTIONAL OUTCOME

To stabilize the knee joint, the anterior cruciate ligament (ACL) is one of the important ligaments. For normal movement and mechanics of the knee joint, ACL is important. If the ACL is torn, people notice problems in stability function of knee joint and there the feeling of ‘giving away’ while weight bearing. The function of anterior cruciate ligament is to restrain translation of the tibia on the femur. However, this role is divided by either anteromedial or the posterolateral bundle, depending on the knee flexion angle. The posterolateral bundle is stretched when the knee is close to full extension; as the knee flexes, the posterolateral bundle loosens and the anteromedial bundle becomes tight. In this report, a 32-year-old male who had a history of twisting of the leg while jogging, started by him since 40 days, lead to partial thickness tear of ACL, minimal joint effusion along the periarticular surface of the right knee and was diagnosed by radiological findings and MRI. As patient was not ready for surgery, he decided to opt for physiotherapy management. The aim of this study is to study effects on functional outcomes after physiotherapy rehabilitation of ACL injury without any invasive procedure.

Range of Motion Comparison Following Total Knee Arthroplasty with and without Patella Resurfacing

Background: Despite significant evaluation, no consensus has been reach for best clinical practice for resurfacing the patella during total knee arthroplasty. Further complicating the ability to reach a conclusion is the inclusion of several different implant types used in previous research. Questions/Purpose: The purpose of this study was to compare post-TKA outcomes between two cruciate retaining implants with or without patella resurfacing. Methods: This retrospective review included 289 patients (380 knees) with a minimum six-month follow-up. All patients received a CR implant, with either a symmetric or an asymmetric tibial baseplate. Post-TKA knee flexion was categorized as <120° and ≥120° and knee extension classified as 0° or >0° and required knee manipulations were noted. Descriptive, nonparametric statistics were performed and a multivariate logistic regression was performed to determine risk of poor range of motion and manipulations. Results: Age was significantly lower in the resurfaced group (p=0.001) and the resurfaced group had longer tourniquet time (p=0.003). The symmetric-resurfaced group had ≥120° of flexion and full extension in 72% and 98.7% of patients, respectively. Compared to symmetric-resurfaced, all other groups had a significantly greater risk of not reaching 120° of knee flexion (p<0.05). There were no significant differences in the risk of requiring a MUA between groups (p>0.06). Conclusions: The effect of resurfacing the patella on post-TKA outcomes may be influenced by tibial implant design. Compared to all other combinations, a symmetric tibial baseplate and resurfaced patella resulted in the highest percentage of patients reaching ≥120°, with a low incidence of manipulations.