Muscle Transplantation Research Articles

Engraftment of FACS Isolated Muscle Stem Cells into Injured Skeletal Muscle.

Skeletal muscle stem cell (MuSC) isolation and transplantation are invaluable tools to assess their capacity for self-renewal and tissue repair. Significant technical advances in recent years have led to the optimization of these approaches, improving our ability to assess MuSC regenerative potential. Here, we describe the procedures for Fluorescent Activated Cell Sorting (FACS)-based isolation of MuSC, their intramuscular transplantation, and analysis of their engraftment into host tissues.

Extracorporeal perfusion - reduced to a one-way infusion.

Extracorporeal perfusion (EP) is moving into focus of research in reconstructive and transplantation medicine for the preservation of amputates and free tissue transplants. The idea behind EP is the reduction of ischemia-related cell damage between separation from blood circulation and reanastomosis of the transplant. Most experimental approaches are based on a complex system that moves the perfusate in a circular course. In this study, we aimed to evaluate if a simple perfusion by an infusion bag filled with an electrolyte solution can provide acceptable results in terms of flow stability, oxygen supply and viability conservation for EP of a muscle transplant. The results are compared to muscles perfused with a pump system as well as muscles stored under ischemic conditions after a one-time intravasal flushing with Jonosteril. With this simple method a sufficient oxygen supply could be achieved and functionality could be maintained between 3.35 times and 4.60 times longer compared to the control group. Annexin V positive nuclei, indicating apoptosis, increased by 9.7% in the perfused group compared to 24.4% in the control group. Overall, by decreasing the complexity of the system, EP by one-way infusion can become more feasible in clinical situations.

The Spinal Accessory Nerve for Functional Muscle Innervation in Facial Reanimation Surgery: An Anatomical and Histomorphometric Study.

Facial reanimation surgery is performed in severe cases of facial palsy to restore facial function. In a 1-stage procedure, the spinal accessory nerve can be used as a donor nerve to power a free gracilis muscle transplant for the reanimation of the mouth. The aim of this study was to describe the surgical anatomy of the spinal accessory nerve, provide a guide for reliable donor nerve dissection, and analyze the available donor axon counts. Dissections were performed on 10 nonembalmed cadavers (measurements of 20 nerves). Surgical anatomy of the spinal accessory nerve was described and distances to important landmarks were measured. Nerve biopsies were obtained of the main nerve trunk distal to the skull base, caudoposterior to the sternocleidomastoid muscle, proximal to the trapezius muscle and at the level of donor nerve harvest to analyze the myelinated axon count throughout the course of the spinal accessory nerve. The donor nerve length and available donor nerve axon count were the primary outcome parameters in this study. The mean donor nerve length was 11.6 cm. The spinal accessory nerve was transferred to the mandibular angle without tension for ideal coaptation to the free muscle transplant. After retraction of the trapezius muscle, a small distal nerve branch that leaves the main nerve trunk at a 90-degree angle medially was used as a landmark to indicate the level of donor nerve transection. On average, 1400 myelinated donor axons were available for innervation of the gracilis muscle transplant. This study gives a practical guide for spinal accessory nerve dissection for its application in facial reanimation as a motor source for the innervation of a free muscle transplant.

Hydroxyethyl starch solution for extracorporeal tissue perfusion

In the field of free flap transfer in reconstructive surgery, the trans- or replanted tissue always undergoes cell damage during ischemia to a more or less strong extent. In previous studies we already showed that conserving muscle transplants by means of extracorporeal perfusion over a period of 6 hours by using a crystalloid solution for perfusion. However, we observed significant edema formation. In this study we aimed at reducing the edema formation by using an iso-oncotic colloid as perfusion solution. This way we wanted to evaluate a possible new application of hydroxyl-ethyl starch in an extracorporeal setup to exploit potential benefits of the colloid.Examined parameters include the muscles' functionality with external field stimulation, histological examination and edema formation. Perfused muscles showed a statistically significant higher ability to exert force compared to nonperfused ones. These findings can be confirmed using Annexin V as marker for cell damage, as perfusion of muscle tissue limits damage significantly compared to nonperfused tissue. Substituting the electrolyte perfusion solution with a colloidal one shows the tendency to reduce the edema formation however without statistical significance.

Feasibility, repeatability, and safety of ultrasound-guided stimulation of the first cervical nerve at the alar foramen in horses.

OBJECTIVE To develop and assess the feasibility, repeatability, and safety of an ultrasound-guided technique to stimulate the first cervical nerve (FCN) at the level of the alar foramen of the atlas of horses. ANIMALS 4 equine cadavers and 6 clinically normal Standardbreds. PROCEDURES In each cadaver, the FCN pathway was determined by dissection, and any anastomosis between the first and second cervical nerves was identified. Subsequently, each of 6 live horses underwent a bilateral ultrasound-guided stimulation of the FCN at the alar foramen 3 times at 3-week intervals. After each procedure, horses were examined daily for 5 days. RESULTS In each cadaver, the FCN passed through the alar foramen; a communicating branch between the FCN and the accessory nerve and anastomoses between the ventral branches of the FCN and second cervical nerve were identified. The anastomoses were located in the upper third of the FCN pathway between the wing of the atlas and the nerve's entry in the omohyoideus muscle. Successful ultrasound-guided electrical stimulation was confirmed by twitching of the ipsilateral omohyoideus muscle in all 6 live horses; this finding was observed bilaterally during each of the 3 experimental sessions. No complications developed at the site of stimulation. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that ultrasound-guided stimulation of the FCN at the alar foramen appears to be a safe and straightforward procedure in horses. The procedure may have potential for use in horses with naturally occurring recurrent laryngeal neuropathy to assess reinnervation after FCN transplantation or nerve-muscle pedicle implantation in the cricoarytenoideus dorsalis muscle.

Adipose-Derived Stem Cells Enhance Axonal Regeneration through Cross-Facial Nerve Grafting in a Rat Model of Facial Paralysis.

Cross-face nerve grafting combined with functional muscle transplantation has become the standard in reconstructing an emotionally controlled smile in complete irreversible facial palsy. However, the efficacy of this procedure depends on the ability of regenerating axons to breach two nerve coaptations and reinnervate endplates in denervated muscle. The current study tested the hypothesis that adipose-derived stem cells would enhance axonal regeneration through a cross-facial nerve graft and thereby enhance recovery of the facial nerve function. Twelve rats underwent transection of the right facial nerve, and cross-facial nerve grafting using the sciatic nerve as an interpositional graft, with coaptations to the ipsilateral and contralateral buccal branches, was carried out. Rats were divided equally into two groups: a grafted but nontreated control group and a grafted and adipose-derived stem cell-treated group. Three months after surgery, biometric and electrophysiologic assessments of vibrissae movements were performed. Histologically, the spectra of fiber density, myelin sheath thickness, fiber diameter, and g ratio of the nerve were analyzed. Immunohistochemical staining was performed for the evaluation of acetylcholine in the neuromuscular junctions. The data from the biometric and electrophysiologic analysis of vibrissae movements, immunohistochemical analysis, and histologic assessment of the nerve showed that adipose-derived stem cells significantly enhanced axonal regeneration through the graft. These observations suggest that adipose-derived stem cells could be a clinically translatable route toward new methods to enhance recovery after cross-facial nerve grafting.

True muscle transplantation for very large angle esotropia: long term results

A very large-angle esotropia could not be corrected by a single eye surgery. We present a series of 16 patients with large angle estoropia treated with muscle transplantation.

Rectus muscle transplantation combined with Jensen procedure for the correction of special strabismus

Objective To evaluate the efficacy of the combined surgery of rectus muscle transplantation and Jensen procedure in the correction of special types of paralytic strabismus. Methods Partial transplantation of the superior and inferior rectus were performed on the horizontal strabismus, while partial transplantation of the medial and lateral rectus were performed on the vertical strabismus. There were two stages in the combined surgery. On the first stage, recession operation of the antagonist muscles associated to the paralyzed or dysplastic muscle was performed. On the second stage, Jensen procedure was performed by combining the transplanted muscle and the paralyzed or dysplastic rectus on the basis of partial rectus transplantation. Results The postoperative eye position was finely corrected and the ocular movement was significantly improved. Besides, part of visual functions were improved, and the complication of anterior segment ischemia wasn't been observed. Conclusion This combined operation not only corrects the eye position of large angle strabismus, but also improves the ocular movement, as well as the binocular visual functions. Key words: Strabismus, paralytic, special type; Rectus muscle transplantation, partial; Jensen procedure; Combined surgery

Facial animation with gracilis muscle transplant reinnervated via cross-face graft: Does it change patients' quality of life?

Gracilis muscle reinnervated by the contralateral facial nerve via cross-graft technique is nowadays considered to be a first-line procedure for facial animation in unilateral palsies. Despite the wide number of papers published analyzing technical aspects, refinements, functional results, and cosmetic outcomes, only a few authors have focused their publications on the patient's perspective and impact on QOL of these procedures. Changes in quality of life in 42 patients treated with gracilis muscle transplant reinnervated via cross-face graft were analyzed through a comparison of preoperative and postoperative items on the Facial Disability Index questionnaire. Statistical evaluation with a paired t-test was performed concerning overall results and specific items modifications. Overall improvement of QOL was found to be highly significant (p=0.001). Mouth and eye functions were the most improved (p=0.001), whereas isolation (p=0.004) and feeling calm and peaceful (p=0.001) were the most improved among the social functions. Facial animation with gracilis neuromuscular transplantation reinnervated with contralateral healthy facial nerve via a cross-graft procedure has been demonstrated to be a safe and reliable procedure in the treatment of congenital or established facial palsies. Our results on quality of life impact support that these operations are not only reliable and safe but also of primary relevance to patients' everyday lives.

Effect of latissimus dorsi flap breast reconstruction on the strength profile of the upper extremity

Objective: Dissection of the latissimus dorsi (LD) flap may have a distinct impact on upper extremity function and strength. To date, insufficient differentiation has been made between loss of muscular strength and shoulder function by dissection of the LD muscle per se and loss of function resulting from all excisional surgery, radiation therapy, and reconstructive procedures at the donor site and the recipient site that may have been combined near the shoulder region. Methods: This study determines the long-term effect of the LD breast reconstruction on the strength profiles of the upper extremity by measuring the isometric torque strength both in seven synergistic- and two contra-movement directions. The Biodex System 3 Pro (Biodex Medical Systems, New York, NY) was used in 12 patients at a mean of 3.5 years after surgery, and in 20 matched controls. Because loss of LD muscle may not result in significant impairment of activities of daily live (ADL) even in cases where objective measurements are decreased, this study simultaneously assessed the subjective function by use of the standardised Disability of Arm, Shoulder and Hand (DASH) questionnaire. Results: This study observed a significant long-term loss of 8.8 Nm or 19% LD torque strength in synergistic movement directions after transplantation of the LD muscle. This loss correlated significantly with an increase of the mean DASH score among the patients. Conclusions: Because no significant loss of contra-movement torque strength was observed, it was concluded that the loss of synergistic torque strength appears to result from the loss of LD function per se.

Restoration of finger and thumb movement using one-stage free muscle transplantation

Objective: Functional reconstruction following severe traumatic muscle loss may cause problems for reconstructive surgeons. In such situations, functioning free muscle transplantation (FFMT) represents an important alternative treatment option.Methods: The clinico-demographic characteristics of 11 patients receiving modified FFMT between 2005–2013 were retrospectively reviewed. The muscle strength, range of joint motion (ROM), total active motion (TAM) of the fingers, and Disability of Arm Shoulder and Hand (DASH) score were adopted to assess the functional results.Results: All FFMTs were performed in the secondary stage. The authors found that the mean ROM, TAM, ratio of TAM compared with the contralateral side, and DASH score were 112 degrees, 150 degrees, 62%, and 22.8, respectively; and eight and nine patients achieved greatly improved grip function and M4 muscle strength, respectively.Conclusion: Using one-stage free muscle transplantation to restore finger and thumb movement simultaneously is an effective method for functional restoration following traumatic multi-muscle loss.

Brown adipose tissue transplantation ameliorates polycystic ovary syndrome

Polycystic ovary syndrome (PCOS), which is characterized by anovulation, hyperandrogenism, and polycystic ovaries, is a complex endocrinopathy. Because the cause of PCOS at the molecular level is largely unknown, there is no cure or specific treatment for PCOS. Here, we show that transplantation of brown adipose tissue (BAT) reversed anovulation, hyperandrogenism, and polycystic ovaries in a dehydroepiandrosterone (DHEA)-induced PCOS rat. BAT transplantation into a PCOS rat significantly stabilized menstrual irregularity and improved systemic insulin sensitivity up to a normal level, which was not shown in a sham-operated or muscle-transplanted PCOS rat. Moreover, BAT transplantation, not sham operation or muscle transplantation, surprisingly improved fertility in PCOS rats. Interestingly, BAT transplantation activated endogenous BAT and thereby increased the circulating level of adiponectin, which plays a prominent role in whole-body energy metabolism and ovarian physiology. Consistent with BAT transplantation, administration of adiponectin protein dramatically rescued DHEA-induced PCOS phenotypes. These results highlight that endogenous BAT activity is closely related to the development of PCOS phenotypes and that BAT activation might be a promising therapeutic option for the treatment of PCOS.

Flow-through anastomosis using a T-shaped vascular pedicle for gracilis functioning free muscle transplantation in brachial plexus injury

OBJECTIVE:In gracilis functioning free muscle transplantation, the limited caliber of the dominant vascular pedicle increases the complexity of the anastomosis and the risk of vascular compromise. The purpose of this study was to characterize the results of using a T-shaped vascular pedicle for flow-through anastomosis in gracilis functioning free muscle transplantation for brachial plexus injury.METHODS:The outcomes of patients with brachial plexus injury who received gracilis functioning free muscle transplantation with either conventional end-to-end anastomosis or flow-through anastomosis from 2005 to 2013 were retrospectively compared. In the flow-through group, the pedicle comprised a segment of the profunda femoris and the nutrient artery of the gracilis. The recipient artery was interposed by the T-shaped pedicle.RESULTS:A total of 46 patients received flow-through anastomosis, and 25 patients received conventional end-to-end anastomosis. The surgical time was similar between the groups. The diameter of the arterial anastomosis in the flow-through group was significantly larger than that in the end-to-end group (3.87 mm vs. 2.06 mm, respectively, p<0.001), and there were significantly fewer cases of vascular compromise in the flow-through group (2 [4.35%] vs. 6 [24%], respectively, p=0.019). All flaps in the flow-through group survived, whereas 2 in the end-to-end group failed. Minimal donor-site morbidity was noted in both groups.CONCLUSIONS:Flow-through anastomosis in gracilis functioning free muscle transplantation for brachial plexus injury can decrease the complexity of anastomosis, reduce the risk of flap loss, and allow for more variation in muscle placement.

Assessing viability of extracorporeal preserved muscle transplants using external field stimulation: a novel tool to improve methods prolonging bridge-to-transplantation time.

Preventing ischemia-related cell damage is a priority when preserving tissue for transplantation. Perfusion protocols have been established for a variety of applications and proven to be superior to procedures used in clinical routine. Extracorporeal perfusion of muscle tissue though cumbersome is highly desirable since it is highly susceptible to ischemia-related damage. To show the efficacy of different perfusion protocols external field stimulation can be used to immediately visualize improvement or deterioration of the tissue during active and running perfusion protocols. This method has been used to show the superiority of extracorporeal perfusion using porcine rectus abdominis muscles perfused with heparinized saline solution. Perfused muscles showed statistically significant higher ability to exert force compared to nonperfused ones. These findings can be confirmed using Annexin V as marker for cell damage, perfusion of muscle tissue limits damage significantly compared to nonperfused tissue. The combination of extracorporeal perfusion and external field stimulation may improve organ conservation research.

Facial paralysis and the role of free muscle transplantation

Facial paralysis can have significant functional, psychological and aesthetic concerns that alter the lives of our patients. These effects can be functional, affecting the eye, nose and mouth, or aesthetic, affecting the symmetry of the face and particularly the mimetic function of smile. Several reanimation procedures have been described to address this. In this chapter, we will outline our technique for reanimation utilizing segmental gracilis muscle transplants to the face. These are innervated either by the contralateral normal 7thnerve via a cross face nerve graft, or a different ipsilateral motor where no 7thnerve is available or would not produce the required result. The other ipsilateral motor that we have found extremely effective is the motor nerve to masseter. This can power a segmental gracilis muscle transplant and lead to excursion that is near normal. These techniques will be described in detail.

Effectiveness of plastic procedures managed with anatomic sub-unit zone on advanced facial paralysis

Objective To investigate the surgical efficacy of the anatomic subunit zone and affiliated procedures on long-standing facial palsy. Methods A total of 533 long-standing facial palsy cases were treated from Mar. 2003 to Dec. 2013 according to the anatomic division into the subunit: eyebrow, upper eyelid and lower eyelid, upper lip and lower lip, and chin. The surgical procedures were done to prevent complications: skin resection for eyebrow plasty, heavy implant for upper eyelid plasty, temporal muscle transfer for lower eyelid plasty, and mini muscle transplantation for lip and chin. We evaluated the surgical effects by Douglas Harrison standard and the paralysis appearance by Stennert international score system. Results Of the above 533 cases evaluated by Douglas Harrison methods, 475 (89%) were good, 48 (9%) were satisfactory, and 6 (1%) were not obviously improved. The paralysis appearance evaluated by Stennert score system showed that 533 (100%) cases were less than 1 of static state score (full score was 4), 475 (89.1%) cases were less than 2 of dynamic state score (full score of 6). Conclusions The proper procedures combined with the deformity location and symptoms with subunit anatomy in facial palsy cases seem to be safe and effective, which not only improve the successful rate of surgery, but also prevent the complications. Key words: Long-standing facial paralysis; Synthetic plasty; Complication; Prevention

Plastic surgical management in lower extremity sarcoma reconstruction

Tumors in the lower extremity with a critical size of over 5 cm diameter should principally be tested for being malignant soft-tissue sarcomas. If a soft-tissue sarcoma is present, radical oncological resection with sufficiently wide surgical margins is the most important cornerstone of curative therapy. No neoadjuvant or adjuvant treatment (radiotherapy or chemotherapy) can replace this treatment approach. Modern techniques of tumor resection as well as plastic-reconstructive surgery permit one to perform radical tumor excision in more than 95% of cases and to close large defects and to largely preserve function of the extremity by transplantation of muscles, tendons and bones as well as transplantations of nerves and blood vessels. The plastic reconstructions after radical tumor resection are often demanding and complex and require intensive interdisciplinary cooperation. This consists of the full spectrum of plastic surgical options, which should be performed in specialized centers and be specifically adapted to the patient and case profile. In this review different options for functional reconstruction after radical oncological removal of soft-tissue sarcomas are presented.

Facial Paralysis Grading System

Various facial paralysis grading systems have been introduced to evaluate the results of both spontaneous recovery and facial palsy reconstruction. The aim of the present study was to introduce and evaluate an objective new and quick Smile Excursion Score system which is readily applicable and easy to follow. It has been applied over the past 25 years for preoperative and postoperative result evaluation of smile reconstruction at Chang Gung Memorial Hospital. A standardized evaluation method was described for the assessment of the upper lip movement preoperatively and postoperatively with at least 1 year follow-up after functioning muscle transplantation. The evaluation was scored by the number of maxillary teeth exposed when smiling with teeth showing. Reliability of this technique was assessed by using 3 independent examiners who each evaluated the smiles of 34 unilateral facial paralysis patients 4 times, creating 408 sets of measurements. The intraclass correlation coefficients for interrater and intrarater reliability exceeded 0.94, which is considered as excellent and reliable. Chuang's Smile Excursion Score system is simple, quick, and accurate in evaluating smile after reanimation of paralyzed face effecting free functional muscle transplantation with no additional tools.

MAR-Mediated Dystrophin Expression in Mesoangioblasts for Duchenne Muscular Dystrophy Cell Therapy

A cornerstone of autologous cell therapy for Duchenne muscular dystrophy is the engineering of suitable cells to express dystrophin in a stable fashion upon differentiation to muscle fibers. Most viral transduction methods are typically restricted to the expression of truncated recombinant dystrophin derivatives and by the risk of insertional mutagenesis, while non-viral vectors often suffer from inefficient transfer, expression and/or silencing. Here we addressed such limitations by using plasmid vectors containing nuclear matrix attachment regions (MAR). Using in vitro transfection and intra muscular transplantation in nude and immunosuppressed mdx mice, we show that clones of mesoangioblast skeletal muscle progenitors can be generated to mediate stable expression from MAR-containing vectors, while maintaining their ability to differentiate in vitro and in vivo and to express dystrophin after transplantation in dystrophic mouse muscles. We conclude that the incorporation of MARs into plasmid vectors may improve non-viral plasmid-based cell therapy feasibility.

Normal and Malignant Muscle Cell Transplantation into Immune Compromised Adult Zebrafish

Zebrafish have become a powerful tool for assessing development, regeneration, and cancer. More recently, allograft cell transplantation protocols have been developed that permit engraftment of normal and malignant cells into irradiated, syngeneic, and immune compromised adult zebrafish. These models when coupled with optimized cell transplantation protocols allow for the rapid assessment of stem cell function, regeneration following injury, and cancer. Here, we present a method for cell transplantation of zebrafish adult skeletal muscle and embryonal rhabdomyosarcoma (ERMS), a pediatric sarcoma that shares features with embryonic muscle, into immune compromised adult rag2E450fs homozygous mutant zebrafish. Importantly, these animals lack T cells and have reduced B cell function, facilitating engraftment of a wide range of tissues from unrelated donor animals. Our optimized protocols show that fluorescently labeled muscle cell preparations from α-actin-RFP transgenic zebrafish engraft robustly when implanted into the dorsal musculature of rag2 homozygous mutant fish. We also demonstrate engraftment of fluorescent-transgenic ERMS where fluorescence is confined to cells based on differentiation status. Specifically, ERMS were created in AB-strain myf5-GFP; mylpfa-mCherry double transgenic animals and tumors injected into the peritoneum of adult immune compromised fish. The utility of these protocols extends to engraftment of a wide range of normal and malignant donor cells that can be implanted into dorsal musculature or peritoneum of adult zebrafish.