Muscle Detachment Research Articles

Structural and Functional Alterations of the Deltoid Muscle After Arthroscopic Rotator Cuff Repair: A 2-Year Longitudinal Observation Study.

Deltoid muscle detachment and atrophy have been reported to occur after shoulder surgery. To investigate the 2-year changes in deltoid muscle structure and function after arthroscopic rotator cuff repair (ARCR) using magnetic resonance imaging (MRI) and electrophysical examination. Case series; Level of evidence, 4. A total of 72 patients (72 shoulders) who underwent ARCR between 2015 and 2020 were enrolled. Whole deltoid muscle volume and regional (anterior, lateral, and posterior) muscle thicknesses were determined on T2-weighted MRI scans of both shoulders taken preoperatively and at 1, 3, 6, 12, and 24 months postoperatively, and their correlations with compound muscle action potentials (CMAPs), shoulder abduction muscle strength, and Constant scores were investigated. Comparison between groups was performed using paired or Student t tests, and the relationship between deltoid muscle volume and various factors was determined using Pearson correlation analysis. The volume of the deltoid muscle on the affected side decreased from 44,369 ± 12,371 mm3 preoperatively to 38,139 ± 10,615 mm3 at 1 month postoperatively (P < .05), representing a 14% decrease. The deltoid muscle volume of the contralateral side also significantly decreased during the same time frame, from 43,278 ± 12,248 to 40,273 ± 11,464 mm3 (P < .05), representing a 7% decrease at 1 month postoperatively. Subsequently, the deltoid muscle volume on both sides recovered to preoperative levels at 12 months and was maintained at 24 months. Only the thickness of the anterior part of the deltoid was markedly decreased, from 13.9 ± 3.7 mm preoperatively to 12.0 ± 3.2 mm at 1 month postoperatively (P < .05), representing a 14% reduction. The CMAP amplitude showed a significant decrease at 1 month postoperatively; however, no significant difference was observed after 12 months when compared with the preoperative values or the values on the contralateral side. Positive correlations were found between deltoid muscle volume and CMAP amplitude at 24 months as well as between deltoid muscle volume and shoulder abduction muscle strength (R 2 = 0.698; P < .05) and Constant score (R 2 = 0.133; P < .05). Our study demonstrated that the early structural and functional decline of the deltoid muscle after ARCR was fully recovered within 1 year, confirming that this procedure does not negatively affect the deltoid muscle.

Correction of Post-Surgical Temporal Hollowing with Adipo-Dermal Grafts: A Case Series.

Background: Surgical dissection and partial detachment of the temporalis muscle during neurosurgical procedures might result in a temporal depression known as "temporal hollowing". Reconstructive procedures to correct this condition include the implantation of synthetic materials (e.g., hydroxyapatite, methacrylate or polyethylene), injection of autologous fat or fillers as well as the use of flaps (e.g., temporo-parietal local flap and latissimus dorsi free flap). However, none of these techniques proved to be an ideal option due to a high complication rate or need for invasive and complex surgery. Adipo-dermal grafts are autologous; the resorption rate seems to be limited and the complexity of the procedure is minor. Moreover, autologous fat grafting can be performed to enhance the final outcome by correcting residual contour deformities. Methods: In this series of five patients, an institutional experience is presented using multi-layered adipo-dermal grafts harvested from the supra-pubic area for the restoration of volume and contour in post-surgical temporal hollowing. During the last follow-up, patients were asked to express their satisfaction, which was assessed by a survey. Results: this approach demonstrates a marked improvement in temporal hollowing associated with a low complication rate and good patient satisfaction. Conclusions: the aim of this consecutive case series is to emphasize the effectiveness of this surgical technique as one of the options to address temporal hollowing.

Pathomechanics of lumbrical and flexor digitorum profundus muscle tears in climbers: A cadaveric model

Lumbrical muscles originate on the flexor digitorum profundus (FDP) tendons and, during fist making, they move in the same direction when FDP muscle produces maximal proximal tendon gliding. Injuries of the bipennate lumbricals have been described when a shear force acts between the origins on adjacent tendons of the FDP, as they glide in opposite directions in asymmetric hand postures. Other structures of the deep flexors complex can be affected during this injury mechanism, due to the so-called quadriga effect, which can commonly occur during sport climbing practise. Biomechanical studies are needed to better understand the pathomechanism. A cadaveric study was designed to analyse the effects of load during the fourth lumbrical muscle injury mechanism. The amount of FDP tendon gliding and metacarpophalangeal (MCP) joint flexion of the 5th finger were calculated. Ten fresh-frozen cadaveric specimens (ten non-paired forearms and hands) were used. The specimens were placed on a custom-made loading apparatus. The FDP of the 5th finger was loaded, inducing isolated flexion of the 5th finger, until rupture. The rupture occurred in all specimens, under a load of 11 kg (SD 4.94), at 9.23 mm of proximal tendon gliding (SD 3.55) and at 21.4° (SD 28.91) of MCP joint flexion. Lumbrical muscle detachment from the 4th FDP was observed, from distal to proximal, and changes in FDP tendons at the distal forearm level too. The quadriga effect can lead to injury of the bipennate lumbrical muscles and the deep flexors complex in the hand and forearm.

Effect of Arthroscopic Acromioplasty on the Isometric Abduction Strength.

Introduction Acromioplasty is a widely performed procedure for various rotator cuff pathologies with good outcomes and high patient satisfaction. However, few studies have focused on its potential complications. Previous cadaveric studies have demonstrated that a considerable portion of the deltoid muscle is detached from its acromial origin following arthroscopic acromioplasty, but the clinical relevance of this muscle detachment has not been investigated. The goal of our research was to examine the influence of arthroscopic acromioplasty on abduction strength and to assess whether acromial anatomy plays a role in any potential effect. Methods From a preliminary sample of 87 individuals who were diagnosed with isolated impingement syndrome and underwent arthroscopic acromioplasty, 74 patients who met the inclusion criteria were ultimately included in the study. The patients were divided into two groups according to their acromion morphology: Bigliani type 2 (33 patients) and type 3 (41 patients). The isometric abduction strength of the two groups was measured by a handheld dynamometer (Isobex®; Cursor AG, Berne, Switzerland) at different abduction angles preoperatively and at the first, third, and sixth months following surgery and was statistically compared. Results Both groups showed reduced abduction strength postoperatively; however, the strength of abduction in the Bigliani type 3 group returned to near preoperative values in the third month. Although increased mean abduction strength was recorded at 30° abduction in the sixth month, this difference was not statistically significant (p=0.78). In the Bigliani type 2 group, compared with those in the sixth-month group, the preoperative abduction strength decreased from 8.32 kg to 6.0 kg (p = 0.047), 6.57 kg to 5.15 (p = 0.025), and 6.1 kg to 4.56 kg (p = 0.006) at 30, 60, and 90° abduction, respectively. Conclusions Arthroscopic acromioplasty decreased isometric abduction strength in patients with a Bigliani type 2 acromion. Patients should be counseled about this loss, which might be especially important for professional athletes and heavy manual workers.

Robotic-assisted plate fixation of the anterior acetabulum - clinical description of a new technique

IntroductionWe present a detailed procedure for the robotic-assisted plate osteosynthesis of an anterior acetabular fracture. The purpose of this work was to describe a robotic-assisted minimally invasive technique as a possible method for reducing complications, pain, and hospitalization. Another goal was to present technical recommendations and to assess potential pitfalls and problems of the new surgical approach.MethodsSurgery was performed in an interdisciplinary setting by an experienced orthopedic surgeon and a urologist. The DaVinci System with standard instruments was used. Reduction was achieved through indirect traction of a pin that was introduced into the femoral neck and direct manipulation via the plate. The plate position and fixation were achieved through 7 additional minimally invasive incisions.ResultsThe technique has multiple advantages, such as no detachment of the rectus abdominal muscle, a small skin incision, and minimal blood loss. Furthermore, this approach might lower the incidence of hernia formation, infection, and postoperative pain.DiscussionWe see the presented technique as a demanding yet progressive and innovative surgical method for treating acetabular fractures with indications for anterior plate fixation.Trial registrationThe study was approved by the local institutional review board (Nr. 248/18).

Bilateral Obturator Osteotomy: A Novel Osteotomy for Bladder Exstrophy Closure

BackgroundAbdominal and pelvic closure remains a challenge during bladder exstrophy initial repair. We aimed to report on the feasibility and results of a novel technique of bilateral obturator osteotomy. MethodsRetrospective study of prospective collected data of children who underwent single-stage delayed bladder exstrophy closure combined with RSTM (Radical Soft Tissue Mobilization) for BEEC (Bladder Exstrophy Epispadias Complex) by the same team at different institutions between December 2017 and May 2021. When pubic approximation was not feasible at the end of the procedure, bilateral obturator osteotomy was performed through the same approach, consisting in bilateral divisions of the ilio-pubic rami, ischio-pubic rami, obturator membrane, and detachment of the internal obturator muscle. Pubic bone fragments were approximated together on the midline. Immobilization in a thermoformed posterior splint was indicated for 3 weeks. The main outcome criterion was the bladder dehiscence rate at 6 months, assessed by physical inspection. Secondary outcome criteria included neurovascular obturator pedicle injury, analyzed during orthopedic physical examination, wound or bone infections, gait acquisition, reported by parents and evaluated during medical examination, and vascular penile impairment, judged by penile and glans coloration. Results17 children (11 males, 6 females) were included, at a median age of 2 months [1–33]; and representing 29% (17/58) of the children with bladder exstrophy who underwent the same surgical approach during the time of study. There was no postoperative bladder dehiscence with a median follow-up of 34 months [6–47]. No complication was observed. Pelvic X-rays showed bilateral normal ossification process. Neither gait abnormality, nor clinical indication of obturator nerve deficiency was observed during follow-up. ConclusionWhen pubic bones approximation is not possible, bilateral obturator osteotomy is a useful adjunct in bladder exstrophy closure, feasible by the pediatric urologist through the same approach, and not requiring external fixator. Level of EvidenceIV.

AN ANATOMICAL STUDY OF THE THORACIC LIMB OF THE GIANT ANTEATER (MYRMECOPHAGA TRIDACTYLA) COMPARED WITH THE DOMESTIC DOG TO GUIDE SURGICAL APPROACHES TO THE HUMERUS AND RADIUS.

The giant anteater (Myrmecophaga tridactyla) is a neotropical mammal considered to be vulnerable to extinction. Recent increased interest in veterinary care in the giant anteater has prompted renewed interest in anatomical descriptions in this species. The terrestrial habits and slow movements of the giant anteater contribute to its susceptibility to vehicular trauma on highways, which is a significant cause of mortality in the species. This study describes the muscular anatomy of the thoracic limb and variations of the long bones with emphasis on the structures surrounding the humerus and radius. It also describes the possible surgical approaches for the management of fractures of humerus and radius, comparing these with the surgical approaches described in dogs (Canis lupus familiaris). Three giant anteater and three domestic dog cadavers, from deaths not related to this project, were used. The medial approach to the humeral diaphysis of the giant anteater resulted in the least tissue trauma, and provided access to the flattest surface for implant attachment. The lateral approach to the radius proved challenging, requiring total detachment of the extensor carpi radialis muscle and incision of the very robust abductor digitorum longus muscle to access the distal diaphysis. Although the giant anteater shares many similarities of the thoracic limb anatomy with the domestic dog, important differences exist. This comparative knowledge will allow veterinary practitioners to directly apply the principles of fracture repair in these species. Safe access to these bones for possible osteosynthesis is essential to allow implant placement and minimize postoperative complications in this species.

The Lateral Supraorbital Approach: 2-Dimensional Operative Video.

The lateral supraorbital approach (LSO), a minimally invasive alternative to the pterional approach, can be used for anterior circulation aneurysms (except distal anterior cerebral artery), some posterior circulation aneurysms, and tumors located around the sellar and suprasellar regions. Performing one-layer myocutaneous flap that is retracted anteriorly, exposure of the superior temporal line, and zygomatic process of the frontal bone and the inferior limit of the craniotomy represent the upper edge of the Sylvian fissure, exposing the anterolateral skull base. Skin incision behind the hairline, one-layer myocutaneous flap retracted anteriorly, minimal detachment of the temporalis muscle, burr hole over the superior temporal line, and craniotomy of 4 cm in diameter (inferior limit of the craniotomy represents the Sylvian fissure). Potential risks include opening of the frontal sinus, entering the orbit and exposure of the orbital fat, wrong craniotomy location, and limited exposure. Inadequate craniotomy size limits instruments maneuverability. To avoid complication, identification of anatomic landmarks, sinus closure, preoperative evaluation of computed tomography scans, and use of neuronavigation are necessary. This requires surgical expertise and familiarity of minimal invasive craniotomies. Anatomic limitations of the LSO include temporomesial region, distal Sylvian +/-, posterior communicating artery aneurysms medial projection, retro carotid space, and carotid cave. For pathologies requiring an additional lateral trajectory, we use an extended LSO, drilling the sphenoid wing through the fronto-pterio-orbital window without drilling of the temporal bone. Additional variations include performing an intradural or extradural clinoidectomy. The patient consented to the procedure and to the publication of their image.

Standardized reduction and palmar plating of dorsally displaced distal radius fractures for safe and atraumatic reconstruction of the anatomy of the radius

Standardization of palmar plate osteosynthesis in order to consequently achieve physiologic anatomy of the distal radius end. Unstable dorsally displaced distal radius fractures or fractures that should be treated functionally. Severe intraarticular joint depression that cannot be reduced with either apalmar or arthroscopic assisted approach. Patient in supine position with the forearm supinated on arm table. Radiopalmar incision along the radial border of the flexor carpi radialis tendon. Detachment of the pronator quadratus muscle from radial to ulnar. Gross reduction with eventual correction of adorsal or radial shift. Placement of the angular stable plate and preliminary fixation with anonangular stable cortical screw in the long hole at the radius shaft. Fluoroscopic control of axial alignment in the anteroposterior view and of correct distal position of the plate in the lateral view under reduction condition. Placement of one or two angular stable screws at the shaft. Under subtle reduction with flexion, ulnar deviation and axial traction placement of two K‑wires via the holes at the distal edge of the plate. These wires mostly keep reduction maintained while reduction maneuver can be paused. Fluoroscopic control in two planes. Replacement of the wires by distal angular stable screws with the help of the wires as an orientation. In case of insufficient reduction, reduction maneuver can be repeated while the first angular stable screw is locked. Final fluoroscopic control in two planes and ulnar deviation, eventually also in tangential view and clinical testing for stability of the distal radioulnar joint. Wound closure only by skin suture. Application of asterile dressing and apalmar cast. Arm consequently in upright position and active and complete movement of fingers. Palmar below-elbow cast for 2weeks, then movement of wrist without exertion. After regular radiographic control 4-5weeks postoperatively, increase of axial load to normal and, if needed, physiotherapy. Clinical control for irritation of tendons by plate or screws after 1year and eventual plate removal.

Poster 269: 4-in-1 Quadricepsplasty for Habitual and Fixed Lateral Patellar Dislocation in Children

Poster 269: 4-in-1 Quadricepsplasty for Habitual and Fixed Lateral Patellar Dislocation in Children

Upper cervical anterior fusion to C2 with temporary infrahyoid muscle detachment: a clinical case series and description of surgical technique

BackgroundAnterior cervical spine surgery to C2 (ACSS-C2) is a challenging procedure that often results in postoperative persistent dysphagia or dyspnea due to injury to the internal branch of the superior laryngeal nerve (iSLN) or the relatively narrow and soft oropharynx. This study aimed to describe the surgical outcomes of our modified approach with temporary infrahyoid muscle detachment during ACSS-C2.MethodsPatients who underwent ACSS-C2 at two institutions between June 2015 and January 2022 were prospectively enrolled. Intraoperatively, we performed temporary detachment of the infrahyoid muscle from the hyoid bone to improve laryngeal mobility and accessibility to C2. This procedure also allowed for the easy identification and preservation of the iSLN. We retrospectively investigated the surgery-related complications and outcomes of bony fusion.ResultsTwelve patients were enrolled in this study; five and seven patients underwent single- and multi-level fusion surgery, respectively. Intraoperative preservation of the iSLN and proper visualization of C2 were achieved in all cases. Subsequent decompression and instrumentation were successfully performed. Two older patients (78 and 81 years) who underwent multi-level fusion experienced transient postoperative dysphagia. None of the patients required unplanned reintubation or revision surgery because of instrumentation failure. Solid bony fusion was achieved in all cases.ConclusionsOur modified approach with temporary infrahyoid muscle detachment during ACSS-C2 reduces the incidence of postoperative persistent dysphagia and dyspnea. However, in older patients at high risk for postoperative dysphagia, multi-level fusion should be avoided, and alternative procedures should be considered.

Appearance of levator ani muscle subdivision defects on level III vaginal support structures in women with and without pelvic organ prolapse: an MRI study

Introduction and hypothesisInjury of the levator ani muscle (LAM) is a significant risk factor for pelvic organ prolapse (POP). The puborectalis (PRM) and pubovisceral (PVM) subdivisions are level III vaginal support structures. The null hypothesis was that there is no significant difference in patterns of LAM subdivisions in healthy nulliparous women. Secondarily, we evaluated the presence of different LAM injury in a POP-symptomatic cohort.MethodsThis retrospective magnetic resonance imaging study included: 64 nulligravidae without any pelvic floor dysfunction (PFD) and 526 women of various parity with symptomatic POP. Primary outcome was PVM and PRM morphology on the axial planes: the attachment site on the pubic bone, and the visible separation/border between the PVM and PRM. The attachment was scored as “normal” or “abnormal”. The “abnormal” attachment was divided in two types: “type I”—loss of the muscle substance, but preservation of the overall muscle architecture—and “type II”—muscle detachment from the pubic bone.ResultsThe puboanal muscle (PAM) subdivision was evaluated as a representative part of the PVM. The PAM and PRM attachments and separation were distinguished in all asymptomatic nulliparae. PAM and PRM attachments did not significantly differ. POP group characteristics were parity 1.9 ± 0.8, instrumental delivery 5.6%, hysterectomy or POP surgery 60%, all Pelvic Organ Prolapse Quantification (POP-Q) stages, LAM defect 77.6% (PRM: 77.1%; PAM: 51.3%). Type I injuries were more frequent (PRM 54.7%; PAM 53.9%) compared with type II (PRM 29.4%; PAM 42.1%).ConclusionsA LAM defect was present in 77.6% of women with symptomatic POP. In PRM and PAM subdivisions type I injury was more frequent than type II.

Does the pronator-sparing approach improve functional outcome, compared to a standard volar approach, in volar plating of distal radius fractures? A prospective, randomized controlled trial

BackgroundThis study aimed to compare functional outcomes of a volar plate osteosynthesis for distal radius fractures (DRF) performed with either a standard volar approach (SVA), which required detachment of the pronator quadratus muscle, or a pronator-sparing approach (PqSA).Materials and methodsThis prospective randomized controlled study included 106 patients scheduled for volar plate osteosyntheses. Patients were allocated to either the SVA group (n = 53) or the PqSA group (n = 53). Patients were blinded to treatment until completion of the study. The primary outcome measure was the Patient-Rated Wrist Evaluation (PRWE). Secondary outcome parameters were the Disabilities of the Arm, Shoulder, and Hand (DASH) score and the Modified Mayo Wrist Score (MMWS). Follow-up examinations were performed at 8 weeks and 3, 6, and 12 months postoperatively.ResultsOverall, 91 patients were included in the final analysis: 48 in the SVA group and 43 in the PqSA group. The two cohorts were not significantly different in demographic characteristics, including age, sex, injuries on the dominant side, type of injury, and fracture classification. We found significant differences between groups at 6 months in the mean PRWE (SVA: 12.3 ± 10.4, PqSA: 18.9 ± 14.11 points) and in the mean DASH score (SVA: 12.3 ± 11.9, PqSA: 19.3 ± 16.7 points), which favoured the SVA. We found no significant differences between groups in the MMWS or in the PRWE and DASH scores at any other time points.ConclusionsThis randomized comparative clinical trial failed to demonstrate that a volar plate osteosynthesis performed with a PqSA could improve the outcome, compared to the SVA, in patients with DRF.Level of evidenceIITrial registration Comparison of Two Volar Plating Systems for Distal Radius Fractures, ClinicalTrials.gov (NCT03474445), registered 22 March 2018, retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT03474445?cond=radius&cntry=AT&draw=2&rank=1

Surgical Site Infection Following the Correction of Adolescent Idiopathic Scoliosis With ApiFix: A Retrospective Study Analyzing Its Incidence and Recurrence.

Background and objective ApiFix (OrthoPediatrics, Warsaw, IN) is an internal brace used for the correction of adolescent idiopathic scoliosis (AIS) classified as Lenke 1 or 5 with a Cobb angle of 35-60 degrees that decreases to ≤30 degrees on lateral side-bending radiographs. Since the indications are very specific, it is not a common procedure. Our study aimed to evaluate the incidence of surgical site infection (SSI) and its recurrence following treatment with ApiFix. Materials and methods A retrospective study of 44 cases of AIS treated at our center from 2016 to 2022 with ApifiX was conducted. Two patients who presented with SSI were initially treated with irrigation and debridement (I&D) following antibiotic therapy. Results A total of 44 patients with a mean age of 15.1 years were evaluated. Two of our patients presented with early-onset infection while one of them presented after the end of treatment with a skin ulcer due to septic screw loosening. The removal of the ApiFix implant revealed a pedicle abscess during the screw removal. Conclusions In this study of 44 patients, we observed two cases of infection and one case of reinfection. Given the limited muscle detachment and short operating time needed for Apifix, statistics suggest that the risk of SSIis always present. Further randomized trials are needed to gather more evidence on this subject.

Facet joint violation after open and percutaneous posterior instrumentation: a comparative study

PurposePosterior instrumentation is the state-of-the-art surgical treatment for fractures of the thoracic and lumbar spine. Options for pedicle screw placement comprise open or minimally invasive techniques. Open instrumentation causes large approach related muscle detachment, which minimally invasive techniques aim to reduce. However, concerns of accurate pedicle screw placement are still a matter of debate. Beside neurological complications due to pedicle screw malplacement, also affection of the facet joints and thus motion dependent pain is known as a complication. The aim of this study was to assess accuracy of pedicle screw placement concerning facet joint violation (FJV) after open- and minimally invasive posterior instrumentation.MethodsA retrospective data analysis of postoperative computer tomographic scans of 219 patients (1124 pedicle screws) was conducted. A total of 116 patients underwent open screw insertion (634 screws) and 103 patients underwent minimally invasive, percutaneous screw insertion (490 screws). ResultsIn the lumbar spine (segments L3, L4, L5), there were significantly more and higher grade (open = 0.55 vs. percutaneous = 1.2; p = 0.001) FJV’s after percutaneously compared to openly inserted screws. In the thoracic spine, no significant difference concerning rate and grade of FJV was found (p > 0.56).ConclusionFJV is more likely to occur in percutaneously placed pedicle screws. Additionally, higher grade FJV’s occur after percutaneous instrumentation. However, in the thoracic spine we didn’t find a significant difference between open and percutaneous technique. Our results suggest a precise consideration concerning surgical technique according to the fractured vertebrae in the light of the individual anatomic structures in the preop CT.

Subfascial dissection and extended temporal muscle detachment for middle fossa approach.

The soft tissue dissection for the middle fossa approach requires adequate management of the neuro, vascular, and muscular structures in order to maximize exposure and diminish morbidities. An incision anterior to the tragus is performed, extending from the zygomatic process to the superior temporal line. The superior temporal artery is exposed, followed by a subfascial dissection of the frontalis nerve. The temporal muscle is dissected and released from the zygoma. All cranial landmarks are exposed for the 5 × 5cm temporal fossa craniotomy. This novel approach provides a safe and adequate access to perform an extended middle fossa craniotomy.

Lyophilized bovine acellular tendon linear fiber material for the reconstruction of attachment structure of paraspinous muscles: an animal in vivo study

Low back pain is common after lumbar spine surgery and the injury from extensive detachment of paraspinal muscles during the surgery may play a vital role. Previously, we prepared a bovine acellular tendon fiber (ATF) material through lyophilization and proved that it could retain its original fibrillar structure and mechanical properties. The objective of this study is to evaluate the effectiveness of this new fiber material used for attachment structure reconstruction of paraspinal muscle. Defect of spinous process, interspinous and supraspinous ligament was established on lumbar spine in rabbit and rat and ATF linear material was implanted to reconstruct the attachment structure. Ultrasound showed the cross-sectional area of the paraspinal muscle in ATF group was larger than that of control group in rats. MRI showed the irregular shape and high signal changes in control group, but regular shape and uniform signal in the ATF group in rabbit. For Electromyogram, the frequency of evoked potential in control group was lower than ATF group and normal rats. HE and Masson staining showed good tissue healing, and immunohistochemical results showed the immune rejection of ATF is significantly lower than that of suture. Reconstruction of the attachment structure of paraspinous muscles with ATF linear material could maintain the morphology, volume and function of paraspinal muscle. ATF material has the potential to be used to manufacture personalized ligaments and other tissue engineering scaffolds.Graphical abstract

Clinical Results According to Inferior Oblique Manipulation in Patients with Inferomedial Blowout Fracture Involving the Orbital Strut.

Detachment of the inferior oblique muscle may be necessary under certain circumstances to repair a large inferomedial orbital fracture involving the orbital strut. This study aimed to evaluate the outcomes of patients who underwent surgeries with and without inferior oblique muscle reattachment after its detachment to repair the orbital wall fractures. Forty patients who underwent repair of combined floor and medial orbital wall fracture involving the orbital strut at a single tertiary institution between January 2014 and December 2020 were reviewed. Groups 1 and 2 comprised 20 patients each, who underwent surgery with inferior oblique muscle detachment without and with reattachment, respectively, and were followed up for at least 6 months postoperatively. Enophthalmos, Goldmann diplopia test, alignment test, ocular motility test, and orbital inferomedial angle ratio were the outcome measures. Statistically significant improvement was observed in ocular motility, diplopia, and enophthalmos postoperatively at the 1- and 6-month follow-up (p < 0.01). The mean postoperative inferomedial angle ratio (102.28 ± 10.62%) was improved significantly compared with the preoperative inferomedial angle ratio (115.61 ± 4.38%) (p = 0.004) in all patients. After surgery, inferior oblique muscle underaction was observed in seven and six patients in groups 1 and 2, respectively, which was associated with preoperative extraocular movement limitation and strabismus. Two patients showed diplopia in both groups at the last follow-up; they had inferior oblique muscle underaction but no enophthalmos. Orbital fracture repair with or without inferior oblique muscle reattachment was clinically effective and safe; however, patients with preoperative strabismus and extraocular motility limitation should be informed of the increased risk of postoperative complications.

Requirement for PINCH in skeletal myoblast differentiation

PINCH, an adaptor of focal adhesion complex, plays essential roles in multiple cellular processes and organogenesis. Here, we ablated PINCH1 or both of PINCH1 and PINCH2 in skeletal muscle progenitors using MyoD-Cre. Double ablation of PINCH1 and PINCH2 resulted in early postnatal lethality with reduced size of skeletal muscles and detachment of diaphragm muscles from the body wall. PINCH mutant myofibers failed to undergo multinucleation and exhibited disrupted sarcomere structures. The mutant myoblasts in culture were able to adhere to newly formed myotubes but impeded in cell fusion and subsequent sarcomere genesis and cytoskeleton organization. Consistent with this, expression of integrin β1 and some cytoskeleton proteins and phosphorylation of ERK and AKT were significantly reduced in PINCH mutants. However, N-cadherin was correctly expressed at cell adhesion sites in PINCH mutant cells, suggesting that PINCH may play a direct role in myoblast fusion. Expression of MRF4, the most highly expressed myogenic factor at late stages of myogenesis, was abolished in PINCH mutants that could contribute to observed phenotypes. In addition, mice with PINCH1 being ablated in myogenic progenitors exhibited only mild centronuclear myopathic changes, suggesting a compensatory role of PINCH2 in myogenic differentiation. Our results revealed a critical role of PINCH proteins in myogenic differentiation.

Monitored Anesthesia Care Protocol for Awake Craniotomy and Patient's Perspective on the Procedure

There is ongoing discussion on pros and cons in terms of different anesthesia protocols for awake craniotomy (AC) with direct brain stimulation. The aim of this study is to share our anesthesia protocol and present our patients' perspectives. We conducted an analysis of prospectively collected data from 53 (54 procedures) consecutive patients. Most of the patients (50) underwent surgery due to primary brain lesions. Eight procedures were performed in patients with lesions in the nondominant hemisphere for language. Four of all procedures were reoperations, and one patient was operated on in awake conditions twice. The psychological evaluation of patients was performed 2 times: 2days before and after surgery. A visual analog scale for pain and stress levels as well as structured interviews was used. Most patients tolerated ACwell. Patients reported that discomfort was mostly related to urinary catheter insertion, head holder placement, and temporal muscle detachment in cases of frontotemporal craniotomies. The intensity of stress measured with the visual analog scale before surgery was negatively associated with age and positively correlated with stress experienced in the operating room. In all patients, we were able to finish the procedure according to the monitored anesthesia care protocol without the need for conversion to general anesthesia. We observed 3 (5.6%) intraoperative seizures that required deepening of sedation. AC using the monitored anesthesia care protocol was a safe and well-tolerated procedure with satisfactory patient experience. Extensive preoperative preparation should be considered a key part of the procedure.