Prevalence of alternative lengthening of telomeres in pediatric sarcomas determined by the telomeric DNA C-circle assay.

Introduction: Alternative lengthening of telomeres (ALT) occurs in sarcomas and ALT cancers share common mechanisms of therapy resistance or sensitivity. Telomeric DNA C-circles are self-primed circular telomeric repeats detected with a PCR assay that provide a sensitive and specific biomarker exclusive to ALT cancers. We have previously shown that 23% of high-risk neuroblastomas are of the ALT phenotype. Here, we investigate the frequency of ALT in Ewing's family sarcoma (EFS), rhabdomyosarcoma (RMS), and osteosarcoma (OS) by analyzing DNA from fresh frozen primary tumor samples utilizing the real-time PCR C-circle Assay (CCA). Methods: We reviewed prior publications on ALT detection in pediatric sarcomas. DNA was extracted from fresh frozen primary tumors, fluorometrically quantified, C-circles were selectively enriched by isothermal rolling cycle amplification and detected by real-time PCR. Results: The sample cohort consisted of DNA from 95 EFS, 191 RMS, and 87 OS primary tumors. One EFS and 4 RMS samples were inevaluable. Using C-circle positive (CC+) cutoffs previously defined for high-risk neuroblastoma, we observed 0 of 94 EFS, 5 of 187 RMS, and 62 of 87 OS CC+ tumors. Conclusions: Utilizing the ALT-specific CCA we observed ALT in 0% of EFS, 2.7% of RMS, and 71% of OS. These data are comparable to prior studies in EFS and OS using less specific ALT markers. The CCA can provide a robust and sensitive means of identifying ALT in sarcomas and has potential as a companion diagnostic for ALT targeted therapeutics.

A systematic review and meta-analysis:comparing the efficacy of the Ilizarov technique alone with lengthening over a nail for lower extremity bone defects.

PURPOSE: The task faced by surgeons becomes significantly more challenging when they encounter lower extremity bone defects due to a variety of causes requiring lengthening. The most discussed and successful approach is the Illizarov technique, or lengthening over a nail (LON):distraction osteogenesis is also widely performed with monoliteral external fixators and intramedullarylengthening nails have increasingly been used in the last decade. METHODS: The data were collected from PubMed, Cochrane Library, Embase, and the Web of Science for all available studies comparing the outcomes of Ilizarov technique alone and LON technique (from January 1, 1997, to November 30, 2023). The outcomes of interest encompassed the external fixation index (EFI) (month/cm), mean duration of follow-up (MFT) (month), length gained (LG) (cm), consolidation index (CIx) (month/cm), and bone healing index (BHI) (month/cm).Complications include pin tract infection rate (PTI), axial deviation rate (AD), occurrence of intramedullary infection (II), delayed consolidation rate (DC), as well as data categorized into three levels of problems, obstacles, and sequelae based on the severity of complications.Two reviewers independently assessed each study for quality and extracted data. The case-control or respective cohort studies were evaluated using the Newcastle-Ottawa scale (NOS) to determine their techniqueological rigor.The Cochrane Collaboration's risk assessment tool was employed to perform quality evaluations for randomized controlled trials. RESULTS: This review included thirteen studies comprising a total of 629 patients.The external fixation index (month/cm) was significantly smaller in the LON technique compared to the Ilizarov technique alone [Mean Difference(MD) = -29.59, 95% CI -39.68--19.49, P < 0.00001].In terms of the mean follow-up time(month) (MD = -0.92, 95% CI -3.49-1.65, P = 0.57), length gained (cm) (MD = -0.87, 95%CI -2.80-1.07, P = 0.38), consolidation index (month/cm) (MD = 0.66, 95% CI -3.44-4.77, P = 0.75), and bone healing index (month/cm) (MD = -3.33, 95% CI -13.07-6.41, P = 0.5), there were no significant differences observed. The LON technique exhibited a lower incidence of axial deviation [Odds Ratio(OR) = 0.06, 95%CI 0.03-0.16, P < 0.00001] and pin tract infection (OR = 0.30, 95%CI 0.18-0.50, P < 0.00001) compared to the Ilizarov technique alone.The remaining complications, such as intramedullary infection rate (OR = 0.93, 95%CI 0.42-2.06, P = 0.85) and delayed consolidation rate(OR = 0.61, 95%CI 0.20-1.86, P = 0.38), did not exhibit statistically significant differences.Our findings demonstrated that the LON technique results in lower incidences of problems (38.5%vs.58.6%) and sequelae (16.6% vs.30.9%) when compared to the Ilizarov technique alone. However, the rates of obstacles (32.4% vs.32.3%) were comparable between the two methods. CONCLUSIONS: Our findings indicate that patients treated with the LON technique experienced significantly shorter external fixation durations and a lower incidence of complications (e.g., pin tract infections and axial deviation) compared to those treated with the Ilizarov technique alone. Other outcome metrics showed no significant differences between the two techniques. However, the LON technique offers substantial benefits, including reduced external fixation times and increased comfort, which enhance patient compliance. In conclusion, the LON technique is a safe, reliable, and effective method for treating tibial and femoral defects.

Calcaneal Lengthening after Tarsal Bone Fusion for Massive Calcaneus Defect Reconstruction.

OBJECTIVES: Calcaneus defect remains challenging with limited strategies for reconstruction. Current methods, including graft transplantation, substitution, and distraction osteogenesis, showed limited advantages with certain shortcomings. Current calcaneus lengthening for partial calcaneus loss reconstruction requires bone loss of less than 35%. We introduced our combination of tarsal bone fusion and gradual lengthening method in treating massive calcaneus loss. METHODS: From January 2015 to December 2021, tarsal bone fusion and calcaneus gradual lengthening were performed in six patients with unilateral massive traumatic loss of the calcaneal tuberosity. A retrospective study was held to evaluate the outcomes of this novel technique. Clinical outcomes were assessed based on the American Orthopedic Foot and Ankle Score (AOFAS). Radiological data were assessed, which included tibio-calcaneal angle (TCA), calcaneal interface angle (CIA), metatarsal declination angle (MDA), angle of longitudinal arch (ALA), and the amount of calcaneus axial lengthening (CAL). RESULTS: The mean calcaneal axial lengthening was 43.8 ± 3.1 mm (range, 39-49.5 mm), and the mean proportion of the lengthened calcaneus was 47.8% ± 3.7% (range, 42.8-55.3%). The mean external fixation time was 104.8 ± 67.5 days (range, 69 to 242 days), and the mean external fixation index was 2.4 ± 1.6 days/cm. All patients stuck to the postoperative follow-up plan with an average follow-up time (FT) of 35.0 ± 6.7 months (range, 26-40 months). Deformities of the injured limbs were all corrected according to radiography. Based on the AOFAS, three excellent and three good results were achieved. CONCLUSION: The Ilizarov technique remains an option for calcaneus reconstruction with a great amount of loss once combined with tarsal bone fusion. The function of the injured foot and ankle can be satisfactorily restored using these techniques in our study. Apart from calcaneus elongation, tarsal bone fusion is somehow necessary to reinforce the proximal segment of the distracted calcaneus for creating a larger distraction callus, correcting concomitant foot deformities, and enhancing hindfoot stability. It is necessary to choose flexibly when tarsal bones should be fused.

Patient-Reported Outcomes After Periodontal Surgical Procedures.

Background Patient satisfaction is the primary focus of the healthcare system. Patient-reported outcome measures (PROMs) are standardized and valid measures obtained directly from the patients and are used to assess and compare the efficacy of healthcare services. This can help improve the service provided by the healthcare system. Therefore, this study aimed to assess PROMs during the first week post-surgery across different periodontal surgical procedures and explore their correlation with surgical duration. Furthermore, the study sought to evaluate the occurrence of postoperative complications. Methodology A total of 30 healthy patients with no systemic history, requiring periodontal surgical procedures such as crown lengthening (CLP), open flap debridement (OFD), and soft tissue grafting (STG) were included in the study. The Visual Analog Scale (VAS) was utilized for gathering PROMs concerning bleeding, swelling, bruising, and pain at intervals of days zero, three, five, and seven after the surgical procedure. Results On the surgical day and over seven days, VAS scores were the lowest for CLP and highest for STG procedures. This result is in accordance with the duration required for surgery. VAS scores for OFD were intermediate. Prevalence of 20% soft tissue graft dehiscence and 40% tenderness on palpation was observed. Swelling and bleeding were noticed in 10% and 20% of OFD cases. Conclusions One week post-surgically, the mean VAS scores were minimum for CLP, whereas maximum for STG procedures. As CLP and OFD require less duration compared to STG, duration plays a significant role in post-surgical outcomes. Prevalence of the post-surgical complications is also related to the duration of the surgery.

What's new in pediatric lower limb reconstruction?

The last years brought many advances relevant to lower limb reconstruction. It feels like guided growth has been looked at from every angle, and still there are new emerging concepts like rotational guided growth waiting to be validated. New hexapod external devices are more accurate and easier to use, and new unilateral fixators allow for more versatile and stable fixation and lengthening. Intramedullary nail lengthening has found its place as a standard procedure for various diagnoses in children and young adults. First results of new and exciting approaches like extramedullary implantable nail lengthening and lengthening plates have been reported. Pharmaceutical treatment has changed the course of certain diseases and must be integrated and considered when making a reconstructive treatment plan. As reconstructive surgery is rapidly advancing so are the technical options for prosthetic fitting, which makes it difficult for caregivers as well as for parents to make the decision between reconstruction and amputation surgery for the most severe cases of congenital deficiencies. This review is highlighting new developments of lower limb reconstruction and is reviewing the current literature.

Single procedure tibialis anterior tendon shortening in combination with Achilles tendon lengthening in unilateral cerebral palsy improves swing phase dorsiflexion in gait.

Purpose: Tibialis anterior tendon shortening combined with tendon Achilles lengthening showed satisfactory short- and long-term outcomes for pes equinus treatment. This retrospective study aimed to evaluate the effectiveness of a single tibialis anterior tendon shortening-tendon Achilles lengthening procedure for treating pes equinus, in a homogeneous unilateral cerebral palsy patient group. Methods: Gait analysis was conducted on 22 unilateral cerebral palsy patients (mean age at surgery = 13.3 years, standard deviation = 3 years) before and within 2.5 years (standard deviation = 0.61 years) after the tibialis anterior tendon shortening-tendon Achilles lengthening procedure. Primary outcome measures included foot drop occurrence in swing, foot dorsiflexion and the first ankle rocker presence compared to healthy reference data. Movement analysis profile and gait profile score were also calculated for the entire gait cycle. The clinical exam and the A2 peak ankle power were analyzed. Statistical analysis used the paired Wilcoxon's sign rank test (p < 0.05). Results: Post-operatively, significant improvements were observed in ankle dorsiflexion during swing (p = 0.0006) and reduced foot drop in swing (p = 0.0107). The occurrence of a first ankle rocker did not significantly change (p = 0.1489). Significant improvements in gait profile score and movement analysis profile for all joints and planes indicate overall gait quality improvement. The foot progression changed significantly (p = 0.0285), with a greater external orientation. Nineteen out of 22 patients were able to quit wearing their ankle foot orthoses. Conclusion: Tibialis anterior tendon shortening and tendon Achilles lengthening combination yielded positive outcomes, showing increased foot dorsiflexion, first ankle rocker presence, and overall improved gait quality. These findings support the effectiveness of this surgical approach for treating pes equinus in children with unilateral spastic cerebral palsy.

Innovative Application of the Ilizarov Technique for Long Nerve Defect Reconstruction: A Detailed Case Report.

BACKGROUND: Traditionally known for bone regeneration, the Ilizarov technique's effectiveness in nerve reconstruction, particularly for extensive nerve damage, has yet to be widely recognized. CASE PRESENTATION: This report presents a case study and proposes the innovative use of the Ilizarov technique for reconstructing extended nerve defects. In this study, we reviewed a 43-year-old male diagnosed with an open fracture of the right tibia combined with soft tissue injury resulting in a mangled injury in which a large part of his right tibial bone and nerve were lost. The patient was cured and the sensorimotor function was recovered after distraction osteogenesis by the Ilizarov technique, which is a unique application of this technique to repair a substantial long nerve defect, a rare occurrence in medical literature. It highlights the method of nerve lengthening, which is achieved by attaching the nerve stump to the bone stump. This approach allows for significant nerve regeneration and ensures a stable progression of the nerve, as the bone stump acts as a carrier, overcoming the challenges of direct nerve lengthening. CONCLUSIONS: The adaptability and effectiveness of the Ilizarov technique in a new area suggests the need to reconsider traditional approaches to complex nerve reconstruction. Placing this case within the context of current medical knowledge underscores the potential of this technique to revolutionize the treatment of extended nerve defects, offering hope for improved outcomes in challenging scenarios.

The results of femoral lengthening using domestic unilateral external fixation and then plating: the first case series in Vietnam.

Introduction and importance: This study aimed to assess the results of femoral lengthening using an external fixator and then plating. Case presentation: This prospective case series study enrolled 11 patients who underwent femoral lengthening and then plating (LATP) between January 2019 and April 2023. The average age of patients was 14.45 ± 7.54 years. One patient with a femur was lengthened and plated, and one tibia was lengthened over a nail simultaneously. The average femoral lengthening was 8.41 ± 1.35 cm. Clinical discussion: The femoral healing result was excellent in seven femurs and good in four femurs; the functional outcome was excellent in five patients and good in six patients. Pin-track infection occurred in all patients. A limited range of motion of knee flexion occurred in eight patients. Femoral varus and procurvatum deviation occurred during distraction in four and two patients. Femoral LATP was considered an attractive alternative to intramedullary lengthening nails in a low-income country. Conclusion: Our research suggests that femoral LATP was an effective method. However, the most common complications were pin-site infection and extensive knee contracture. Further research should be done with a larger sample size and longer follow-up time. Level of evidence: Level IV-prospective observational case series study.

Preliminary Outcomes of Calcaneal Body Lengthening for the Calcaneus Shortening.

For lengthening irregular bones, such as calcaneus, there are few reports in the literature. This study aimed to introduce the treatment strategy and preliminary outcomes for calcaneus shortening using calcaneal body lengthening. From January 2017 to January 2022, calcaneal lengthening was conducted for three patients (two males and one female) who suffered from traumatic calcaneal shortening. The Achilles tendon was lengthened in one patient. After osteotomy of the calcaneus, an Ilizarov frame was used to gradually (1 mm/day) distract the calcaneal fragment. The lengthening procedure was stopped when the calcaneal height and length were restored based on radiography. The fixator was removed after bone union. The average follow-up length was 18 months (range, 14-24 months). X-ray was used for radiological assessments. Patients reported satisfaction using the 100-mm visual analog scale (VAS). Clinical outcome was evaluated following the American Orthopedic Foot and Ankle score. All data were assessed by two physicians blind to clinical assessments. The wound healed primarily in three cases. The bone got solid union without refracture and malunion. The distraction time was 30 days (range, 25-45 days). The fixation time was 113.3 days (average, 80-150 days). Calcaneal lengthening was 26 mm (range, 15-43 mm). The height and length of the calcaneus were restored nearly to the same as the opposite foot. The mean preoperative calcaneal pitch angle increased from 2.6 degrees to an average of 19.0 degrees after the surgery. The AOFAS score increased from 60.0 to 86.0. One patient experienced pin infection. The infection healed after changing the dressing. Calcaneal lengthening using an Ilizarov external fixator is a preferable technique to restore the length and height of the calcaneus and can achieve satisfactory foot function.

[Perioperative nursing for patients undergoing autologous dermis grafting for penile girth augmentation and penile lengthening].

OBJECTIVE: To explore the perioperative nursing methods of autologous dermal transplantation for penile girth enhancement combined with penile lengthening surgery. METHODS: Summarize the perioperative nursing data of 5 patients with small penis who underwent autologous groin dermal transplantation for penile girth enhancement combined with penile lengthening surgery. RESULTS: After comprehensive perioperative nursing, all 5 patients recovered well after the surgery. The preoperative APPSSI scores of the patients were 4.60±0.48, which were all less than 6 points. The postoperative APPSSI scores at 2 months, 6 months, and 12 months were 9－12 (10.6±1.02), 10－12 (11.2±0.98), and 10－12 (11.2±0.98) respectively, showing satisfaction with the surgical outcomes. There was a statistically significant difference compared to the preoperative APPSSI scores (ï¼°<0.05). The preoperative SAS scores were 45－58 (52.2±4.35), and the SAS scores at 2 months, 6 months, and 12 months postoperatively were 31－40 (34.2±3.31), 30-41 (35.8±3.65), and 33－40 (35.6±2.33) respectively, indicating a reduction in anxiety levels after the surgery, with a statistically significant difference compared to the preoperative SAS scores (P<0.05). The preoperative IIEF-5 scores were 7－15 (10.4±2.87), and the IIEF-5 scores at 2 months, 6 months, and 1 year postoperatively were 16－24 (19.8±2.71), 18－25 (21.2±2.48), and 18－24 (20.8±2.39) respectively, showing a significant improvement postoperatively, with statistical significance (P<0.05). The preoperative NPTR examination showed a sustained erection time of 18－25 (21.2±2.59) minutes, and the NPTR examination at 2 months, 6 months, and 1 year postoperatively showed sustained erection times of 18－24 (21.8±2.28), 20-25 (23.4±2.30), and 24－27 (25.4±1.14) minutes respectively. There was no statistically significant difference in the sustained erection time at 2 months and 6 months postoperatively compared to preoperative NPTR examination, but there was a statistically significant difference at 12 months postoperatively (P<0.01). CONCLUSION: Comprehensive perioperative nursing is an important factor in achieving high satisfaction with the surgery, promoting postoperative recovery, and improving the quality of sexual life for patients undergoing autologous groin dermal transplantation for penile girth enhancement combined with penile lengthening surgery.

HLTF resolves G4s and promotes G4-induced replication fork slowing to maintain genome stability.

G-quadruplexes (G4s) form throughout the genome and influence important cellular processes. Their deregulation can challenge DNA replication fork progression and threaten genome stability. Here, we demonstrate an unexpected role for the double-stranded DNA (dsDNA) translocase helicase-like transcription factor (HLTF) in responding to G4s. We show that HLTF, which is enriched at G4s in the human genome, can directly unfold G4s in vitro and uses this ATP-dependent translocase function to suppress G4 accumulation throughout the cell cycle. Additionally, MSH2 (a component of MutS heterodimers that bind G4s) and HLTF act synergistically to suppress G4 accumulation, restrict alternative lengthening of telomeres, and promote resistance to G4-stabilizing drugs. In a discrete but complementary role, HLTF restrains DNA synthesis when G4s are stabilized by suppressing primase-polymerase (PrimPol)-dependent repriming. Together, the distinct roles of HLTF in the G4 response prevent DNA damage and potentially mutagenic replication to safeguard genome stability.

Effects of detraining on neuromuscular function and structural adaptations following once- or twice-weekly eccentric resistance training in older adults.

BACKGROUND: Eccentric resistance training elicits greater preservation of training-induced muscular adaptations compared with other training modalities, however the detraining profiles of different training dosages remain unknown. AIMS: To examine the detraining effects following once- or twice-weekly eccentric-specific resistance training in older adults. METHODS: Twenty-one older adults (age = 70.5 ± 6.0 year) completed a 12-week detraining period following the 12-week eccentric training programmes with neuromuscular function and muscle structure assessed six (mid-detraining) and 12 (post-detraining) weeks following training cessation. RESULTS: From post-training to post-detraining, no significant regression of the training-induced improvements (collapsed group data reported) occurred in power (0%), strength (eccentric = 0%, isometric = 39%), or explosive strength over numerous epochs (0-32%), resulting in values that remained significantly greater than at pre-training. However, significant regression in the improvements in muscle thickness (91%) and fascicle angle (100%) occurred, resulting in values that were not significantly greater than pre-training. DISCUSSION: The limited regression in neuromuscular function following a 12-week detraining period has important implications for supporting eccentric exercise prescription in older adults who often face periods of inactivity. However, further work is required to develop an effective maintenance dosage strategy that preserves improvements in muscle structure. CONCLUSIONS: Eccentric resistance training elicits improvements in the neuromuscular function of older adults, which are sustained for at least 12 weeks after eccentric training cessation.

From Simple to Complex: Preserving and Reconstructing the Traumatized Thumb.

Traumatic thumb injuries significantly affect overall hand function and may result in considerable disability. Reconstructing the traumatized thumb requires a detailed preoperative assessment of the defect and evaluation of the patient's social history and medical comorbidities. Reconstructive techniques can be stratified by the level of thumb injury. The goals of thumb reconstruction are to restore length, stability, mobility, and sensibility. This article reviews reconstructive principles and operative techniques for reconstructing the traumatized thumb.

Joint Preservation Surgery Using Supramalleolar Osteotomy Combined with Posterior Tibial Tendon Release and Lateral Ligament Augmentation in Advanced Varus Ankle Arthritis.

Background: Recent studies utilizing weight-bearing computed tomography have identified abnormal internal rotation of the talus in advanced varus ankle arthritis (VAA) with a large talar tilt (TT), influenced by the posterior tibial tendon (PTT). This study aimed to evaluate the clinical and radiographic results of supramalleolar osteotomy (SMO) combined with PTT release and lateral ligament augmentation for VAA with a large TT. Methods: From January 2015 to September 2018, 15 patients with VAA and a large TT (greater than 5°) underwent SMO combined with PTT release. Clinical results, including visual analog scale (VAS) for pain, American Orthopedic Foot and Ankle Society (AOFAS) ankle-hindfoot score, and ankle osteoarthritis scale (AOS), were assessed. Radiographic results were assessed with various parameters, including medial distal tibial angle (MDTA), anterior distal tibial angle (ADTA), talar tilt (TT), talus center migration (TCM), Meary angle, hindfoot alignment angle (HAA), and hindfoot moment arm (HMA) on foot and ankle weight-bearing radiographs. Clinical and radiographic results were evaluated preoperatively and at the last follow-up. Results: VAS, AOFAS ankle-hindfoot score, and AOS improved significantly from 7.5, 54.4, and 72.6 preoperatively to 3.1, 82.5, and 34.5 postoperatively, respectively. All radiographic parameters exhibited significant changes postoperatively, with the exception of the Meary angle, which demonstrated no significant change. Four patients exhibited improvement in radiographic stage postoperatively; however, average radiographic stage did not significantly improve postoperatively in all patients. One patient progressed to end-stage arthritis postoperatively, necessitating additional ankle arthrodesis. Conclusions: In conclusion, lengthening and lateral ligament augmentation combined with bony realignment procedures may be a reasonable option for treating VAA with a large TT greater that 5°.

Postoperative Calcaneocuboid Joint Subluxation and Midtarsal Joint Changes in Pediatric Idiopathic Flexible Flatfoot Treated With Calcaneal Lengthening Osteotomy: A Midterm Follow-up Study.

BACKGROUND: Calcaneal lengthening osteotomy (CLO) is one of the main surgical options for treatment of pediatric idiopathic flexible flatfoot (FFF). Reportedly, calcaneocuboid (CC) joint subluxation occurs after CLO; however, its effect on the midfoot remains unclear. This study aimed to investigate the radiologic midterm results after CLO treatment in pediatric idiopathic FFF. METHODS: We evaluated 23 pediatric patients with idiopathic FFF aged ≥8 years, who underwent CLO from 1999 to 2017 owing to moderate to severe flatfoot deformity (assessed by visual inspection). Patients aged between 8 and 14 years were included (mean follow-up: 6.3 years; range, 3.1-11.4 years). Anteroposterior and lateral weightbearing foot radiographs were assessed for radiologic parameters preoperatively and at the 3-month, 1-year, and final follow-ups postoperatively. RESULTS: All patients had immediate postoperative radiologic correction of the flatfoot deformity, and these improvements were maintained until the final follow-up. The mean allograft length inserted was 9 (range, 8-10) mm. There was increased CC joint subluxation after CLO, but it improved continuously until the final follow-up. A CC joint spur was newly noted in 1 case. There were 24 cases (24/39, 61.5%) of talonavicular (TN) joint spurs at the final follow-up, but 19 of these were already present on the preoperative radiographs (19/24, 79.2%). Further, the new-onset TN joint spurs were not associated with preoperative clinicoradiologic factors. CONCLUSION: In pediatric patients with idiopathic FFF receiving CLO treatment, preoperative radiologic angles improved. CC joint subluxation increased after surgery; however, it gradually reduced without evidence of CC joint arthritic changes over the time period studied in this cohort.

The Prevalence of Persistent Toe Walking in Children with and without Autism Spectrum Disorder and the Odds of Subsequent Surgery.

Persistent toe walking is associated with autism spectrum disorder. The true prevalence of persistent toe walking and odds of progression to surgery in children with and without autism remains unclear. This retrospective descriptive study identified patients ages 3 - 17 years who were enrolled in our healthcare system over a two-year period. Using international classification of disease codes, we identified all children with autism and persistent toe walking, and excluded children with conditions that may independently cause toe walking. Data on Achilles lengthening surgeries, sex, race and body mass index was gathered. The toe walking prevalence amongst children with and without autism was calculated. Multivariable logistic regression analysis controlling for sex, race and body mass index was used to determine independent risk factors for persistent toe walking and surgery. Of the children who met inclusion criteria (N = 284,925), 4,622 (1.6%) had persistent toe walking. Prevalence of persistent toe walking was higher amongst children with autism (6.3% versus 1.5%, p < 0.01), as were odds of persistent toe walking (OR 4.13, 95% CI 3.74 - 4.56, p < 0.01). Males and White patients had higher odds of persistent toe walking compared to females and patients of any other race, respectively (p < 0.01 for all). Although children with autism and toe walking had higher rates of surgery than their counterparts without autism (4.3% versus 2.6%, p = 0.04), this difference was not significant after controlling for sex, race and BMI (OR 1.59, 95% CI 0.95 - 2.69, p > 0.05). LEVEL OF CLINICAL EVIDENCE: III.

The impacts of muscle-specific force-velocity properties on predictions of mouse muscle function during locomotion.

Introduction: The accuracy of musculoskeletal models and simulations as methods for predicting muscle functional outputs is always improving. However, even the most complex models contain various assumptions and simplifications in how muscle force generation is simulated. One common example is the application of a generalised ("generic") force-velocity relationship, derived from a limited data set to each muscle within a model, uniformly across all muscles irrespective of whether those muscles have "fast" or "slow" contractile properties. Methods: Using a previously built and validated musculoskeletal model and simulation of trotting in the mouse hindlimb, this work examines the predicted functional impact of applying muscle-specific force-velocity properties to typically fast (extensor digitorum longus; EDL) and slow-contracting (soleus; SOL) muscles. Results: Using "real" data led to EDL producing more positive work and acting significantly more spring-like, and soleus producing more negative work and acting more brake-like in function compared to muscles modelled using "generic" force-velocity data. Extrapolating these force-velocity properties to other muscles considered "fast" or "slow" also substantially impacted their predicted function. Importantly, this also further impacted EDL and SOL function beyond that seen when changing only their properties alone, to a point where they show an improved match to ex vivo experimental data. Discussion: These data suggest that further improvements to how musculoskeletal models and simulations predict muscle function should include the use of different values defining their force-velocity relationship depending on their fibre-type composition.

[VY-plasty for chronic quadriceps tendon rupture]. / VY-Plastik bei chronischer Ruptur der Quadrizepssehne.

OBJECTIVE: Lengthening of the quadriceps tendon for dehiscence in chronic rupture. INDICATIONS: Chronic rupture of the quadriceps tendon with delayed diagnosis or failure of primary refixation with a dehiscence between 1 and 5 cm. CONTRAINDICATIONS: Dehiscence of more than 5 cm. SURGICAL TECHNIQUE: Reopen the old incision and lengthen it to about 20-25 cm if necessary. Visualize the rupture. Debridement of the tendon and the insertion. Measurement of the dehiscence. Creation of a V-flap and reinforcement with a holding seam. Gradual mobilization of the V­flap distally and reinforcement with two strong suture cords (braided suture size 5). Drilling of three obliquely ascending drill holes through the patella. Transosseous threading of the two reinforcement cords through the three drill holes. Knotting the reinforcement cords on the patella. Closure of the gap between the patella and the superficial tendon leaflet with a #2 braided suture. Closure of the gap between the V­flap and the quadriceps tendon. POSTOPERATIVE MANAGEMENT: Six weeks of partial weight-bearing with 20 kg in a straight orthosis. Mobility: weeks 1-4 E/F 0-0-60, weeks 5 and 6 E/F 0-0-90. RESULTS: We were able to follow-up 8 patients (mean age: 63.1 ± 4.5 years), who underwent this surgery in the manner described. All patients were able to perform an active extension postoperatively. The Lysholm score increased from 46.4 (±â€¯5.4) points preoperatively to 81.6 (±â€¯6.5) points postoperatively. No further rupture was detectable in the ultrasound examination at latest follow-up after an average of 27 (18-36) months.

Pseudoaneurysm as an unusual complication in bone lengthening.

One of the risks of distraction osteogenesis-based techniques is the development of vascular complications, such as pseudoaneurysms associated with the osteotomies performed or the fixation elements of the external fixator used in the procedure. Pseudoaneurysm are formed when the tunica adventitia of the artery is injured, resulting in a gradual and persistent blood extravasation into the surrounding tissues that is encapsulated and connected to the arterial lumen. This report describes a rare case of a late-presentation pseudoaneurysm in the anterior tibial artery resulting from a tibial lengthening procedure aimed at addressing a leg length discrepancy in a 57-year-old female with severe peripheral neuropathy resulting from long-standing poorly controlled diabetes mellitus. We describe the diagnostic process, the treatment options and confirm how the shape of the bony callus can be a reliable indicator of this pathology, as has already been described in the literature.