Successful restoration of knee extension after transferring of the anterior branch of the obturator nerve: a case study.

Objective: Femoral nerve palsy occurs after trauma, surgical procedures and tumors and leads to loss of quadriceps functions, disability and decreased quality of life. The aim of this report was to describe a successful restoration of knee extension by transferring the anterior branch of the obturator nerve to selective branches of the femoral nerve at the thigh level.Methods: We describe a 27-year-old male who had quadriceps femoris muscle paralysis after surgical evacuation for retroperitoneal hematoma five months ago. Since proximal stump of femoral nerve was not accessible, we transferred anterior branch of obturator nerve to selective branches of femoral nerve for reconstruction of quadriceps femoris muscle.Results: After four months, he regained quadriceps muscle strength M3 and began to walk. He achieved full muscle strength (M5) nine months after surgery and was able to walk up-stairs easily 14 months after surgery and atrophy of the quadriceps was improved.Conclusion: The anterior branch of the obturator nerve is an available donor nerve with an excellent functional recovery for the reconstruction of knee extension when proximal stump of femoral nerve is not reachable or the repair needs a long graft.

Anatomical study of the masseteric and obturator nerves: Application to face transplant and reanimation procedures.

The masseteric nerve (MN) and the anterior branch of the obturator nerve (ON) that innervate the transferred gracilis muscle have proved highly efficient for reanimating paralyzed facial muscles when muscle transfer is required. Previous researchers have published the total axonal load for myelinated fibers in both nerves. However, the real motor axonal load has not been established. We performed the study on 20 MN and 13 ON. The segments of the MN and the ON were embedded in paraffin, sectioned at 10 µm, and stained following a standard immunohistochemical procedure using anti-choline acetyltransferase to visualize the motor fibers. The MN has a higher axonal load than the ON. There were statistically significant differences between the axonal load of the proximal segment of the MN and the ON. These findings confirm that end-to-end anastomoses between the MN and the ON should preferably use the proximal segment. However, MN neurotomy should ideally be performed between the proximal and distal segments, preserving innervation to the deep fascicles. Our results show that the MN is ideal as a donor motor nerve for reinnervating transplanted muscle for dynamic reanimation of the paralyzed face. The neurotomy should ideally be performed between the first and second collateral branches of the MN. Clin. Anat. 32:612-617, 2019. © 2019 Wiley Periodicals, Inc.

The Distal Stump of the Intramuscular Motor Branch of the Obturator Nerve Is Useful for the Reconstruction of Long-Standing Facial Paralysis Using a Double-Powered Free Gracilis Muscle Flap Transfer.

BACKGROUND: Double innervation of the transferred muscle with the contralateral facial nerve and the ipsilateral masseteric nerve has recently been reported by some authors. The aim of this study was to assess the utility of our procedure of double innervation of free gracilis muscle for reconstruction of long-standing facial palsy. PATIENTS AND METHODS: In our department, 6 cases of long-standing facial paralysis (4 cases of complete palsy and 2 of incomplete palsy) were reconstructed using a free gracilis muscle double innervated with the masseteric and contralateral facial nerves. The patient age ranged from 37 to 79 years (average 56.7 ±â€Š15.7). In our procedure, the intramuscular motor branch of the transferred muscle was identified and sutured to the ipsilateral masseteric nerve in an end-to-end fashion, and the obturator nerve of the transferred muscle was sutured to the cross-facial nerve graft, which was coapted with the contralateral facial nerve by end-to-end suturing. RESULTS: All patients were followed up for >18 months and recovered their smiling function. The voluntary movement of the transferred muscle with teeth clenching was observed at approximately 4.7 months, and this movement combined with contralateral mouth angle elevation was observed at approximately 9.5 months after the surgery. CONCLUSIONS: Our experience suggests that the distal stump of the intramuscular motor branch of the obturator nerve may be useful for facial reanimation via double-powered free gracilis muscle flap transfer.

Obturator Nerve Transfer to the Branch of the Tibial Nerve Innervating the Gastrocnemius Muscle for the Treatment of Sacral Plexus Nerve Injury.

BACKGROUND: Lower-limb function is severely impaired after sacral plexus nerve injury. Nerve transfer is a useful reconstructive technique for proximal nerve injuries. OBJECTIVE: To investigate the clinical effectiveness and safety of transferring the ipsilateral obturator nerve to the branch of the tibial nerve innervating the medial head of the gastrocnemius muscle to recover knee and ankle flexion. METHODS: From 2007 to 2011, 5 patients with sacral plexus nerve injury underwent ipsilateral obturator nerve transfer as part of a strategy for surgical reconstruction of their plexuses. The mean patient age was 31.4 years (range, 19-45 years), and the mean interval from injury to surgery was 5.8 months (range, 3-8 months). The anterior branch of the obturator nerve was coapted to the branch of the tibial nerve innervating the medial head of the gastrocnemius muscle by autogenous nerve grafting. RESULTS: Patient follow-up ranged from 24 to 38 months. There were no complications related to the surgery. Three patients recovered to Medical Research Council grade 3 or better in the medial head of the gastrocnemius muscle. Thigh adduction function was not affected in any patient. CONCLUSION: Knee and ankle flexion can be achieved by transferring the anterior branch of the obturator nerve to the branch of the tibial nerve innervating the medial head of the gastrocnemius muscle, which is useful for balance. This procedure can be used as a new method for treating sacral plexus nerve injury. ABBREVIATION: MRC, Medical Research Council.

Obturator nerve anatomy and relevance to one-stage facial reanimation: limitations of a retroperitoneal approach.

BACKGROUND: Single-stage facial reanimation with a partial gracilis muscle coapted to the contralateral facial nerve seems an optimal surgical solution yet has not supplanted the two-stage approach. Insufficient obturator nerve length may limit reach to sizable contralateral facial nerve branches (possibly necessitating interposition nerve grafting), compromise optimal muscle positioning, or risk nerve coaptation under tension. This study evaluates whether retroperitoneal obturator nerve dissection would effectively lengthen the nerve, thus obviating the aforementioned limitations. METHODS: Ten hemifaces and obturator nerves of five cadavers were dissected. Facial measurements included modiolus to contralateral facial nerve branches of sufficient size at the vertical line of the lateral orbital rim. Obturator nerve measurements included gracilis neurovascular hilum to (1) obturator canal entry point (ab), (2) intraobturator canal point where additional adductor branches are inseparable by internal neurolysis (ac), and (3) retroperitoneal point of separation between anterior and posterior obturator branches (ad). Obturator nerve reach for cross-facial nerve coaptation was assessed. RESULTS: Successful coaptation was achieved with obturator nerve dissection to point b approximately 20 percent of the time, to point c 60 to 70 percent of the time, and to retroperitoneal point d 90 to 100 percent of the time CONCLUSIONS: Successful coaptation to large contralateral facial nerve branches is feasible in 90 to 100 percent of cases if the entire anterior obturator branch is harvested. However, the increased risk of retroperitoneal dissection and sacrifice of additional adductor branches decreases the viability of this approach. Obturator canal dissection (point c) provides reach in 60 to 70 percent of cases, but short interposition nerve grafting may prove necessary.

Obturator nerve transfer for femoral nerve reconstruction: anatomic study and clinical application.

BACKGROUND: Femoral nerve lesion causes significant disability. In many cases, the availability of the proximal stump is in question and further complicates surgical management by severely limiting reconstructive options and precluding nerve graft reconstruction. The purpose of this report is to describe the successful restoration of quadriceps function by distal nerve transfer at the level of the thigh without functional donor morbidity and the findings of cadaveric dissections of the obturator and femoral nerve branches. METHODS: Eight fresh frozen cadaveric lower limbs were dissected at the region of the groin and thigh. Two patients were referred to us with complete femoral nerve palsy and unavailability of the proximal femoral nerve for reconstruction by conventional methods. Distal nerve transfers were performed using the anterior branch of the obturator nerve and in one case, the motor branch to the tensor fasciae latae to reinnervate the rectus femoris and vastus medialis muscles. RESULTS: As measured in cadaveric specimens, the transferable lengths of each donor nerve branch when used to innervate any combination of quadriceps muscles provide plenty of length for tension-free end-to-end coaptations. One patient recovered 3 to 4/5 Medical Research Council grade knee extension and the other 4+/5 knee extension. The latter patient is able to walk, run, and use stairs normally, whereas the former still has difficulty with fast ambulation, running, and stairs. CONCLUSION: The authors present a novel reconstructive approach that yields good clinical outcomes, as well as an anatomic study that demonstrates the feasibility of this technique.

Anterior branch of the obturator nerve: a novel motor autograft for complex peripheral nerve reconstruction.

BACKGROUND: Autografting is the optimal reconstruction for many nerve gaps, because the retained nerve architecture serves as a regenerative scaffold. Experimental evidence suggests that motor regeneration is favored with the use of a motor nerve graft as compared with sensory nerve autografts, but clinical descriptions are lacking in the literature. As a novel solution, we report our use of the anterior branch of the obturator nerve as a large segment motor nerve graft with minimal functional morbidity. CASE: A 17-year-old boy reported progressive weakness and atrophy of the right thigh due to a multifascicular femoral nerve tumor. Motor branch defects of 7 and 4 cm were reconstructed using autografts from the motor nerve to the gracilis (MNG). The patient noted gradual clinical improvement in quadriceps strength, and repeat electromyography at 8- and 13-month follow-ups demonstrated improving motor unit action potentials and quadriceps muscle recruitment. DISCUSSION: The MNG is readily available, with an average total donor length of 11.4 cm. The use of motor nerve grafts is supported by experimental models demonstrating superior nerve regeneration. The MNG is a compelling choice for clinical use because donor-site morbidity is minimized by redundancy of the thigh adductors and a favorable incision location. CONCLUSION: This is the first published description of successful use of the anterior branch of the obturator nerve as a robust donor motor nerve graft. Clinical use of this graft may maximize functional outcomes and minimizes donor-site morbidity compared with traditional sensory nerve grafts.

Free tissue transfer for the treatment of facial paralysis.

Long-standing facial paralysis requires the introduction of viable, innervated dynamic muscle to restore facial movement. The options include regional muscle transfer and microvascular free tissue transfer. There are advantages and disadvantages of each. Briefly, the regional muscle transfer procedures are reliable and provide immediate return of movement. However, the movement is not of a spontaneous mimetic nature. Free tissue transfer, in contrast, offers the possibility of synchronous, mimetic movement. It does, however, require a prolonged healing time in comparison with that of regional muscle transfer. The choice is made by physician and patient together, taking into account their preferences and biases. Muscle-alone free tissue transfer is our preferred option for reanimation of uncomplicated facial paralysis without skin or soft tissue deficits. Combined muscle and other tissue (most are skin flap) is another preferred option for more challenging complex facial paralysis with skin or soft tissue deficits after tumor excision. Gracilis flap is the author's first choice of muscle transplantation for both reconstructions. From 1986 to 2006, gracilis functioning free muscle transplantation (FFMT) was performed at Chang Gung Memorial Hospital for facial reanimation in 249 cases of facial paralysis. The main etiology is postoperative complication and Bell's palsy. The innervating nerve comes mostly from contralateral facial nerve branches, few from ipsilateral facial nerve due to tumor ablation, and from ipsilateral motor branch to masseter or spinal accessory nerve due to Möbius syndrome. We have evolutionally used a short nerve graft (10 to 15 cm) to cross the face in the first stage; after a 6- to 9-month waiting period, gracilis FFMT was performed for the second stage of the reconstruction. The technique of evolution has shown encouraging results to achieve the goal of rapid restoration and fewer scars on the donor leg.

[Electrophysiological study on motor nerve implantation after ectopic transplantation of skeletal muscle in rat].

OBJECTIVE: To study the effect of motor nerve implantation after ectopic transplantation of skeletal muscle on nerve regeneration in rat. METHODS: Sixty Sprague-Dewley male 8-monthold rats were randomly divided into 3 groups: control group, in situ implantation group and ectopic transplantation group. In control group, obturator nerve controlling right gracilis was cut off. In in situ implantation group, the right gracilis was cut off and replanted to its original site, and the obturator nerve was implanted to the muscle. In ectopic transplantation group, the right gracilis was cut off and transplanted to the muscle of the left leg, and the obturator nerve was implanted to the muscle. After 25 weeks, the neurophysiological information was collected through electromyography and the weight of the muscle was measured. RESULTS: The potential without control of the nerve existed in control group. There were no significant differences in latency, amplitude and conduct velocity between in situ implantation group and ectopic transplantation group (P > 0.05). The atrophy of gracilis was dominant in control group, the weight of the muscle was 158.0 +/- 19.3 mg. The weights of the muscle were 509.6 +/- 14.5 mg in ectopic transplantation group and 516.8 +/- 12.7 mg in in situ implantation group, showing no significant difference (P > 0.05). The weights of the muscle in in situ implantation and ectopic transplantation group were larger than that in control group, showing significant difference (P < 0.05). CONCLUSION: Motor nerve implantation after ectopic transplantation of skeletal muscle could prevent the atrophy of the muscle and resume partial function of nerve.