Free functional muscle transfer for lower extremity reconstruction.

BACKGROUND: Free functional muscle transfer is a reconstructive strategy for the reconstruction of lost muscle units in the lower extremity after oncologic resection, trauma, compartment syndrome, or severe nerve injuries. Under appropriate circumstances, free functional muscle transfer may be the only suitable reconstructive option. This article reviews the underlying principles of free functional muscle transfer, its application to lower extremity reconstruction, appropriate patient selection, and surgical techniques. METHODS: The underlying principles of free functional muscle transfer, its application to lower extremity reconstruction, appropriate patient selection, and surgical techniques are presented. Commonly used donor muscles appropriate for each type of functional defect are discussed. A review of recent publications on free functional muscle transfer in the lower extremity was also performed. RESULTS: Good functional recovery with a Medical Research Council grade of up to 4/5 and full range of motion can be attained with free functional muscle transfer. Clinical outcomes and specific parameters for published case series in lower extremity free functional muscle transfer are presented and an illustrative case. CONCLUSION: Free functional muscle transfer is a suitable treatment for the appropriate patient to restore essential functions and potentially regain ambulation. However, additional published clinical outcomes are needed and represent a major area for further investigation.

A Simple Brochure Improves Disposal of Unused Opioids: An Observational Cross-Sectional Study.

BACKGROUND: We evaluated the effectiveness of a simple, low-cost educational brochure in improving disposal rates of unused opioids after outpatient upper extremity surgery. METHODS: This cross-sectional study enrolled eligible adult patients from a peripheral nerve clinic between November 2017 and September 2018. Patients either received or did not receive the educational brochure, which outlined a simple method to dispose of unused opioids and completed a survey at 2 weeks after surgery. We compared the proportion of patients who disposed of unused opioids after surgery between the group that had received the brochure and the group that had not. Categorical data were analyzed with χ2 test, proportions data with binomial tests, and numerical data with Mann-Whitney U test, all with a significance level of P < .05. RESULTS: There were 339 survey respondents. Nineteen patients who did not meet inclusion criteria were excluded. Of the 320 remaining patients, 139 received the brochure and 181 did not. An additional 55 patients were excluded due to preoperative opioid use. Overall, 35.3% of recipients and 38.3% of those who did not receive the brochure used all of their prescribed opioid medication (P = .625; confidence interval = -14.6%-8.8%). Among patients with unused opioid medication, a significantly higher proportion of brochure recipients disposed of the medicine compared with those who did not receive the brochure (46.7% vs 19.6%, P < .001). CONCLUSIONS: Distribution of an educational brochure significantly improved disposal of unused opioids after surgery. This easily implemented intervention can improve disposal of unused opioids and ultimately decrease excess opioids available for diverted use in the community.

Adductor magnus muscle transfer to restore knee extension: Anatomical studies and clinical applications.

BACKGROUND: Loss of knee extension causes significant impairment. Though nerve-based reconstruction is preferable in cases of femoral nerve palsy or injury, these surgeries are not always appropriate if the pathology involves the quadriceps muscles or presentation too late for muscle reinnervation. Muscle transfers are another option that has been underutilized in the lower extremity. We describe the successful restoration of knee extension by adductor magnus muscle transfer without functional donor morbidity, along with anatomical considerations. METHODS: Ten fresh frozen cadaveric lower limbs were dissected at the groin and thigh. In addition, three patients presented with femoral nerve palsy for which nerve-based reconstruction was not appropriate because of late presentation. In these patients, adductor magnus muscle transfers were performed, along with sartorius, gracilis, and tensor fasciae latae transfers if available and healthy. RESULTS: In cadavers, the pedicle for the adductor magnus is at the level of the gracilis and adequate for muscle transfer, with sufficient weavable tendon length. The only major structure at risk is the femoral neurovascular bundle, which is in a reliable anatomic position. Two patients recovered 4/5 active knee extension and ambulation without assistive devices. A third required reoperation for a loosened tendon weave, after which the noted improved stability and strength with ambulation but did not regain strong active knee extension and continued to require a cane. CONCLUSIONS: We present a novel reconstructive approach for loss of quadriceps function in patients, which yields good clinical outcomes, with anatomic and technical details to demonstrate the utility of this technique. Ongoing evaluation of optimal technique and rehabilitation to maximize functional outcomes is still needed.

Stem cell-based approaches to enhance nerve regeneration and improve functional outcomes in vascularized composite allotransplantation.

PURPOSE OF REVIEW: The current review will discuss the current understanding of nerve regeneration in vascularized composite allotransplantation (VCA). The success of proximal arm and leg transplants has been hampered by the limitations of nerve regrowth across long distances resulting in poor regeneration and functional recovery. Relevant research in stem-cell therapies to overcome these issues will be reviewed. RECENT FINDINGS: The effect of rejection on nerve regeneration in the VCA may be unpredictable and may be quite different for the nerve allograft. The issues that limit functional outcome are likely common to both VCA and proximal nerve injuries or replantation. Stem-cell therapies have focused on augmenting Schwann cell function and appear promising. SUMMARY: A better understanding of the effects of transplant rejection on nerve regeneration and function, as well as the factors that affect regeneration over long distances may inform further therapeutic approaches for improvement.

Lower Extremity Reconstruction with Free Gracilis Flaps.

Background There have been significant advancements in lower extremity reconstruction over the last several decades, and the plastic surgeon's armamentarium has grown to include free muscle and fasciocutaneous flaps along with local perforator and propeller flaps. While we have found a use for a variety of techniques for lower extremity reconstruction, the free gracilis has been our workhorse flap due to the ease of harvest, reliability, and low donor site morbidity. Methods This is a retrospective review of a single surgeon's series of free gracilis flaps utilized for lower extremity reconstruction. Demographic information, comorbidities, outcomes, and secondary procedures were analyzed. Results We identified 24 free gracilis flaps. The duration from injury to free flap coverage was ≤ 7 days in 6 patients, 8-30 days in 11 patients, 31-90 days in 4 patients, and > 90 days in 3 patients. There were 22 (92%) successful flaps and an overall limb salvage rate of 92%. There was one partial flap loss. Two flaps underwent incision and drainage in the operating room for infection. Two patients developed donor site hematomas. Four patients underwent secondary procedures for contouring. Our subset of pediatric patients had 100% flap survival and no secondary procedures at a mean 30-month follow-up. Conclusion This study demonstrates the utility of the free gracilis flap in reconstruction of small- to medium-sized defects of the lower extremity. This flap has a high success rate and a low donor site morbidity. Atrophy of the denervated muscle over time allows for good shoe fit, often obviating the need for secondary contouring procedures.

Internal mammary artery perforator propeller flap for contralateral mastectomy defect: A case report.

The internal mammary artery perforator (IMAP) flap can be used as either loco-regional or free flap, and provides thin flexible coverage for defects of the chest wall and cervical regions. In this report, we present a bilateral mastectomy case in which the left mastectomy defect was closed with an IMAP propeller flap harvested from the right breast. Our patient with a history of left breast conservation therapy was diagnosed invasive ductal carcinoma in her left breast 14 years later. On physical examination, the patient's left breast displayed the stigmata of radiotherapy including dark discoloration and firmness to palpation, compared to contralateral pendulous breast. After bilateral mastectomy, an IMAP flap with a size of 26 cm × 11 cm was harvested from right chest and was transposed 180 degrees clockwise in a propeller fashion to the left mastectomy defect without any tension. The flap survived without any complication and the patient was free of recurrence or metastases during the follow-up of 18 months. The patient was satisfied with the outcome. IMAP propeller flap could be harvested safely to the anterior axillary fold in the subcutaneous fat plane. It may provide a large skin paddle especially in large breasted women. © 2016 Wiley Periodicals, Inc. Microsurgery 36:507-510, 2016.

Free Functional Muscle Transfers to Restore Upper Extremity Function.

Free functional muscle transfer provides an option for functional restoration when nerve reconstruction and tendon transfers are not feasible. To ensure a successful outcome, many factors need to be optimized, including proper patient selection, timing of intervention, donor muscle and motor nerve selection, optimal microneurovascular technique and tension setting, proper postoperative management, and appropriate rehabilitation. Functional outcomes of various applications to the upper extremity and the authors' algorithm for the use of free functional muscle transfer are also included in this article.

Predictive Value of Nutritional Markers for Wound Healing Complications in Bariatric Patients Undergoing Panniculectomy.

BACKGROUND: Hypoproteinemia and nutritional deficiencies are common after bariatric surgery, and although massive weight loss (MWL) patients experience increased wound complication rates, the association has not been causatively determined. OBJECTIVES: This study investigated preoperative nutritional parameters and wound complications in MWL patients (postbariatric and diet-controlled) undergoing panniculectomy at 2 academic institutions. METHODS: One hundred sixty-one consecutive patients undergoing elective panniculectomy after bariatric surgery or diet-controlled weight loss were identified. Patient demographics and nutritional indices (serum protein, albumin, and micronutrient levels) were analyzed. Complications including wound separation, infection, and operative debridements were compared. Post hoc comparisons tested for correlation between complications and nutritional markers. RESULTS: Postbariatric patients lost an average of 151 lb and presented at an average of 32 months after gastric bypass. Diet-controlled weight loss patients lost an average of 124 lb. Despite MWL, albumin levels were higher in the bariatric group (3.8 vs 3.4 g/dL, P < 0.05). Conversely, bariatric patients experienced increased wound complications (27% vs 14%; P < 0.05). Factors which were found to correlate to increased risk of wound dehiscence and infection were elevated body mass index at time of panniculectomy and amount of tissue removed. Multivariate analysis did not show serum albumin or percent weight loss to independently predict complications. CONCLUSIONS: Bariatric patients presenting for elective operations are at risk for protein and micronutrient deficiency. Despite aggressive replacement and normalization of nutritional markers, bariatric patients experience increased wound complications when compared to nonbariatric patients and traditional measures of nutritional evaluation for surgery may be insufficient in bariatric patients.

Motor and sensory nerve transfers in the forearm and hand.

BACKGROUND: Peripheral nerve injury is a significant problem affecting more than 1 million people around the world each year and poses major challenges to the plastic and reconstructive surgeon. For high upper extremity nerve injuries, distal muscle reinnervation and functional outcomes are generally poor. Tendon transfer has been the traditional reconstructive option in these cases to restore hand function. More recently, nerve transfers have been described in the forearm and hand to recover hand and wrist function and critical sensation. METHODS: This article reviews the surgical principles, donor nerve options, indications, and outcomes of distal nerve transfers for high upper extremity nerve injuries. RESULTS: The functional results of nerve transfers to date have been comparable to tendon transfers. The primary advantage is the potential for individual finger motion from a donor nerve with singular function. The disadvantage is the longer recovery time required for muscle reinnervation. CONCLUSIONS: Nerve transfers are a viable option for peripheral nerve injuries distal to the brachial plexus. The choice of management will depend on the patient's individual goals and priorities in terms of the need or desire for individual finger movement and the length of the recovery period.

Nerve transfers.

This article provides an update of the current state of motor and sensory nerve transfers for the functional reconstruction of proximal and distal nerve lesions of the upper extremity. General principles, indications, surgical options, and functional outcomes are summarized for conventional transfers used in brachial plexus reconstruction, more recently described distal nerve transfers for isolated nerve injuries in the extremity, and sensory nerve transfers performed both proximally and distally.

Direct radial to ulnar nerve transfer to restore intrinsic muscle function in combined proximal median and ulnar nerve injury: case report and surgical technique.

A distal median to ulnar nerve transfer for timely restoration of critical intrinsic muscle function is possible in isolated ulnar nerve injuries but not for combined ulnar and median nerve injuries. We used a distal nerve transfer to restore ulnar intrinsic function in the case of a proximal combined median and ulnar nerve injury. Transfer of the nonessential radial nerve branches to the abductor pollicis longus, extensor pollicis brevis, and extensor indicis proprius to the motor branch of the ulnar nerve was performed in a direct end-to-end fashion via an interosseous tunnel. This method safely and effectively restored intrinsic function before terminal muscle degeneration.

Nerve gaps.

SUMMARY: Peripheral nerve injury is a significant problem affecting greater that 1 million people around the world each year and poses major challenges to the plastic and reconstructive surgeon. When primary nerve repair is not possible, several options for management of the nerve gap include a nerve autograft, nerve conduit, and acellular nerve allograft. For extensive and proximal nerve injuries, cellular nerve allografts and nerve transfers may be considered. This article reviews the indications and outcomes for each option, as in many cases more than one option may be acceptable.

Nerve regeneration in rat limb allografts: evaluation of acute rejection rescue.

BACKGROUND: Successful nerve regeneration is critical to the functional success of composite tissue allografts. The present study was designed to characterize the effect of acute rejection on nerve regeneration and functional recovery in the setting of orthotopic limb transplantation. METHODS: A rat orthotopic limb transplantation model was used to evaluate the effects of acute rejection on nerve regeneration and motor recovery. Continuous administration of FK506 (full suppression), administration of FK506 for the first 8 of 12 weeks (late rejection), or delayed administration of FK506/dexamethasone following noticeable rejection (early rejection) was used to preclude or induce rejection following limb transplantation. Twelve weeks postoperatively, nerve regeneration was assessed by means of histomorphometric analysis of explanted sciatic nerve, and motor recovery was assessed by means of evoked muscle force measurement in extensor digitorum longus muscle. RESULTS: A single episode of acute rejection that occurs immediately or late after reconstruction does not significantly alter the number of regenerating axonal fibers. Acute rejection occurring late after reconstruction adversely affects extensor digitorum longus muscle function in composite tissue allografts. CONCLUSIONS: Collected data reinforce that adequate immunosuppressant administration in cases of allogeneic limb transplantation ensures levels of nerve regeneration and motor functional recovery equivalent to that of syngeneic transplants. Prompt rescue following acute rejection was further demonstrated not to significantly affect nerve regeneration and functional recovery postoperatively. However, instances of acute rejection that occur late after reconstruction affect graft function. In total, the present study begins to characterize the effect of immunosuppression regimens on nerve regeneration and motor recovery in the setting of composite tissue allografts.

Transfer of the extensor digiti minimi and extensor carpi ulnaris branches of the posterior interosseous nerve to restore intrinsic hand function: case report and anatomic study.

PURPOSE: To present a technique for restoration of ulnar intrinsic function using a nerve transfer of the extensor carpi ulnaris (ECU) and extensor digiti minimi (EDM) nerve branches of the posterior interosseous nerve (PIN) to the deep branch of the ulnar nerve in the forearm when the anterior interosseous nerve is unavailable. METHODS: We dissected 6 cadaveric upper extremities to identify the location of the EDM and ECU branches of the PIN and their distance to the ulnar nerve near the wrist. We present a case of a high combined median and ulnar nerve injury. We performed transfer of the EDM branch and 1 of the branches to the ECU of the PIN to the motor component of the ulnar nerve for intrinsic hand function. RESULTS: Our anatomic data demonstrate the branching pattern of the PIN and the length of regeneration and nerve graft required. Our patient required a 10-cm nerve graft, and the length of regeneration to reach the wrist was 19 cm. The patient recovered useful but incomplete reinnervation of the intrinsic muscles and rated hand recovery at 70%. CONCLUSIONS: Transfer of the EDM and ECU branches of the PIN to the motor component of the ulnar nerve is feasible with the use of a nerve graft. Using some of the branches to the ECU as well increases the axonal load to maximize muscle reinnervation. CLINICAL RELEVANCE: Proximal ulnar nerve injuries with paralysis of the intrinsic hand muscles lead to severe disability. Distal nerve transfers eliminate key factors that result in poor outcomes by allowing for faster muscle reinnervation. This nerve transfer had no functional donor morbidity and could be useful in the setting of a combined high median and ulnar nerve injury.

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.

Nerve transfers: indications, techniques, and outcomes.

This article provides an update of the current strategies of motor and sensory nerve transfers for peripheral nerve lesions of the upper extremity. Indications, techniques, and outcomes are summarized for both well-established transfers used in the management of proximal and brachial plexus injuries as well as those more recently developed for more distal and isolated nerve injuries in the forearm and hand.

Multiple costimulatory blockade in the peripheral nerve allograft.

BACKGROUND: In the nerve allograft model, costimulation blockade has permitted good regeneration but is still inferior to the nerve isograft. We hypothesize that a short course of multiple costimulatory pathway blockade will be more effective in inhibiting the redundancy of the immune response and improve nerve regeneration through the nerve allograft. METHODS: The murine sciatic nerve allograft model was used to reconstruct a 1 cm sciatic nerve gap. Treatment consisted of the inhibition of the CD40, CD28/B7 and ICOS pathways and was compared with only single or double costimulation blockade. Assessment methods included quantitative histomorphometry and ELISPOT assay to quantify the host immune response after 3 weeks post-operatively. RESULTS: Triple costimulation blockade permitted regeneration through the nerve allograft that was equivalent to the nerve isograft. A short course of three doses was more effective than a single dose for all combinations tested. ELISPOT assay demonstrated minimal in vitro immune response with a short course of double or triple pathway-blocking agents. CONCLUSION: Costimulation blockade, especially with the simultaneous inhibition of multiple pathways, remains a promising strategy to promote regeneration through the peripheral nerve allograft, and may be uniquely suited to the temporary immunosuppressive requirements of the peripheral nerve allograft.

Tacrolimus (FK506): Safety and Applications in Reconstructive Surgery.

Tacrolimus (FK506) is a macrolide immunosuppressive drug that is approved for the prevention of allograft rejection. It is a standard component of immunosuppressive regimens currently in use for organ and reconstructive tissue transplants. The experimental literature has demonstrated potential efficacy in the management of other diseases for which transplantation does not play a role. The ability of tacrolimus to modulate the immune system and inhibit T cell activation provides a potential benefit for the treatment of disorders in which autoimmune phenomena are central to their pathogenesis such as rheumatoid arthritis and inflammatory bowel disease. Tacrolimus also has well-established neuroprotective and neuroregenerative properties through both similar and different mechanisms that have been extensively demonstrated in both small and large animal models. However, as a potent immunosuppressive agent, it can cause serious adverse effects, some of which are irreversible and potentially life threatening. This article reviews its safety under different therapeutic requirements and applications in both allogeneic and autogenous tissue reconstruction.

Nerve transfer for elbow flexion in radiation-induced brachial plexopathy: a case report.

Radiation-induced brachial plexopathy is an uncommon but devastating late complication seen in patients receiving radiation therapy to the chest wall and axilla. Treatment options are unfortunately limited. We report a case of a 59-year-old woman treated with radiation therapy for breast cancer 12 years earlier, who presented with loss of elbow flexion and marked shoulder weakness. Electromyogram and intraoperative stimulation of the musculocutaneous nerve branches were consistent with a proximal motor nerve conduction block. Microsurgical transfer of median and ulnar nerve fascicles to the biceps and brachialis branches of the musculocutaneous nerve, respectively, were performed. The patient recovered MRC grade 4/5 elbow flexion after surgery. The characteristics of this disorder and surgical treatment options are reviewed.