Donor Muscle Research Articles

Subdivision of the sural nerve: Step towards individual facial reanimation

Long term facial paralysis is a serious affliction and upsetting for the patient. Dynamic facial reanimation has become the treatment of choice. Various techniques that use different donor muscles have been developed since the first functional muscle transplant for facial paralysis more than 30 years ago. The concept of using a single muscle was refined into the use of dividable muscle slips such as serratus muscle or separate muscular subunits to avoid the resulting mass movements. Because the results are still not satisfactory, efforts were put into also dividing the donor nerve transplant into corresponding subunits to create a continuous line of individual action. Twenty human cadaveric sural nerves were successfully dissected into three completely separate subunits, transecting the interfascicular bridges. This anatomical study gives the potential to allow an independent triple innervation of three separate serratus anterior muscle slips, so decreasing further the mass movement after facial reanimation.

Complications, Pitfalls, and Outcomes After Chest Wall Reconstruction

Chest wall and mediastinal wounds may be life-threatening. Although modern reconstruction methods with various muscle flaps have reduced morbidity and mortality, chest wall reconstruction presents unique challenges. Major categories of adverse outcomes include (1) persistent infection; (2) interference with respiratory mechanics; (3) functional deficits of the shoulder; and (4) hernias. Persistent infection may be resolved by providing coverage via muscle or omental flap, performing thorough debridement, filling the "dead space" with adequate volume, buttressing repair of visceral fistulae, and covering exposed prosthetic material with vascularized flaps. Potential deficits in respiratory mechanics and shoulder function may be avoided by stabilizing the chest wall skeleton and decreasing donor muscle functional loss. Hernias may be minimized by maintaining visceral "right of domain" to the chest and abdominal cavities. Complex reconstructive cases represent an intricate interplay of physiology, structural protection, and aesthetic considerations and require integration of several management principles.

Comparison of Wrist and Elbow Stabilization Following Pinch Reconstruction in Tetraplegia

Individuals with spinal cord injuries resulting in tetraplegia may receive tendon transfer surgery to restore grasp and pinch function. These procedures often involve rerouting the brachioradialis (Br) and the extensor carpi radialis longus tendons volar to the flexion-extension axis of the wrist, leaving the extensor carpi radialis brevis (ECRB) muscle to provide wrist extension strength. The purpose of this study was to determine whether externally stabilizing the wrist after transfer procedures would improve the ability to activate the transferred Br and resulting pinch force, similar to the effect observed when the elbow is externally stabilized. We used a one-way repeated-measures study design to determine the effect of 3 support conditions on muscle activation and lateral pinch force magnitude in 8 individuals with tetraplegia and previous tendon transfer surgeries. Muscle activation was recorded from Br and ECRB with intramuscular electrodes and from biceps and triceps muscles with surface electrodes. We quantified pinch strength with a 6-axis force sensor and custom grip. We recorded measurements in 3 support conditions: with the arm self-stabilized, with elbow stabilization, and with elbow and wrist stabilization. Pairwise differences were tested using Wilcoxon signed-rank tests. Maximum effort pinch force magnitude and Br activation were significantly increased in both supported conditions compared with the self-supported trials. The addition of wrist stabilization had no significant effect compared with elbow stabilization alone. A strong ECRB has adequate strength to extend the wrist, even after multiple transfers that contribute an additional flexion moment from strong activation of donor muscles. Anatomical and functional differences between the wrist and elbow musculature are important determinants for self-stabilizing joints proximal to the tendon transfer. The ability to increase Br activation and resulting pinch force may be determined, in part, by the individual's ability to develop new coordination strategies.

Mechanical Feasibility of Immediate Mobilization of the Brachioradialis Muscle After Tendon Transfer

Tendon transfer is often used to restore key pinch after cervical spinal cord injury. Current postoperative recommendations include elbow immobilization in a flexed position to protect the brachioradialis-flexor pollicis longus (BR-FPL) repair. The purpose of this study was to measure the BR-FPL tendon tension across a range of wrist and elbow joint angles to determine whether joint motion could cause repair rupture. We performed BR-to-FPL tendon transfers on fresh-frozen cadaveric arms (n = 8) and instrumented the BR-FPL tendon with a buckle transducer. Arms were ranged at 4 wrist angles from 45 degrees of flexion to 45 degrees of extension and 8 elbow angles from 90 degrees of flexion to full extension, measuring tension across the BR-FPL repair at each angle. Subsequently, the BR-FPL tendon constructs were removed and elongated to failure. Over a wide wrist and elbow range of motion, BR-FPL tendon tension was under 20 N. Two-way analysis of variance with repeated measures revealed a significant effect of wrist joint angle (p<.001) and elbow joint angle (p<.001) with significant interaction between elbow and joint angles (p<.001). Because the failure load of the repair site was 203 +/- 19 N, over 10 times the loads that would be expected to occur at the repair site, our results demonstrate that the repair has a safety factor of at least 10. Our tendon force measurements support the assertion that the elbow joint need not be immobilized when the BR is used as a donor muscle in tendon transfer to the FPL. This is based on the fact that maximum passive tendon tension was only about 20 N in our cadaveric model and the failure strength of this specific repair was over 200 N. We suggest that it is possible to consider performing multiple tendon transfers in a single stage, avoiding immobilization, which may adversely affect functional recovery. These results must be qualified by the fact that issues unique to living tissues such as postoperative edema and tendon gliding cannot be accounted for by this cadaveric model.

Update of the Physiology and Biomechanics of Tendon Transfer Surgery

Tendon transfer surgery has evolved over the past decade. Unique muscle properties have been elucidated in terms of potential force generation, excursion, and metabolic properties. The choice of an appropriate donor muscle is becoming more of a science than an art. The measurement of sarcomere length has progressed from the laboratory into surgery. Methods of tendon coaptation have advanced to allow early mobilization. This article reviews recent advances in our understanding of tendon transfer surgery of the hand and upper extremity.

Long Head of the Triceps Muscle Transfer for Active Elbow Flexion in Arthrogryposis

Arthrogryposis is a condition characterized by symmetric, nonprogressive joint contractures and weak or absent musculature that is present at birth. The amyoplasia form is the most common, and in this group, the elbow is frequently involved, typically in an extension contracture bilaterally. Active elbow flexion is weak or absent, but active extension is spared. This elbow dysfunction poses a significant disability for affected children. Sensation and cognitive development is normal in children with arthrogryposis, and as a group they demonstrate a remarkable degree of adaptability to their deformities. The goal of any treatment is to facilitate the child's functional independence. This article describes the surgical technique of transfer of the long head of the triceps into the proximal ulna to provide active elbow flexion in children with arthrogryposis. The goal of the procedure is to reliably achieve antigravity active flexion while preserving active extension. It has the advantages of technical simplicity and minimal donor site morbidity. By adding this procedure to the existing options for treating this challenging condition, a surgeon is better able to tailor intervention to an individual child's strength and available donor muscles.

Asynchronous Muscle and Tendon Adaptation After Surgical Tensioning Procedures

Donor muscles are often highly stretched in tendon transfer surgery. Despite literature reports that showed adaptation of the serial sarcomere number to moderate stretch, little is known regarding adaptation to stretch outside of the physiological range (commonly seen in clinical tendon transfer). This study was performed to evaluate muscle-tendon-unit adaptation to tendon transfer surgery in an animal model. Thirty-seven male New Zealand White rabbits were used for muscle analysis, and twenty-five of those rabbits were also used for biological analysis of the tendons after the experiment. The extensor digitorum muscle of the second toe was transferred at a specific sarcomere length of 3.7 microm, chosen to be near the end of the descending limb of the rabbit sarcomere length-tension curve. Animals were killed at five time points, at which complete muscle architectural analysis as well as measurements of tendon dimension, tendon water content, and tendon cytokine transcript levels were performed. As expected, a rapid increase in the serial sarcomere number (mean and standard error of the mean, 4658 +/- 154 in the transferred muscle compared with 3609 +/- 80 in the control muscle) was found one week after the surgery. From this time point until eight weeks, this increased serial sarcomere number paradoxically decreased, while the sarcomere length remained constant. Eventually, at eight weeks, it reached the same value (3749 +/- 83) as that in the control muscle (3767 +/- 61). Tendon adaptation was delayed relative to muscle adaptation, but it was no less dramatic. Tendon length increased by 1.43 +/- 0.74 mm over the eight-week time period, corresponding to a strain of 15.55% +/- 4.08%. To our knowledge, this is the first report of biphasic adaptation of the serial sarcomere number followed by tendon adaptation, and it indicates that muscle adapts more quickly than tendon does. Taken together, these results illustrate a complex and unique interaction between muscles and tendons that occurs during adaptation to stretching during tendon transfer.

Use of genetically modified muscle and fat grafts to repair defects in bone and cartilage

We report a novel technology for the rapid healing of large osseous and chondral defects, based upon the genetic modification of autologous skeletal muscle and fat grafts. These tissues were selected because they not only possess mesenchymal progenitor cells and scaffolding properties, but also can be biopsied, genetically modified and returned to the patient in a single operative session. First generation adenovirus vector carrying cDNA encoding human bone morphogenetic protein-2 (Ad.BMP-2) was used for gene transfer to biopsies of muscle and fat. To assess bone healing, the genetically modified ("gene activated") tissues were implanted into 5mm-long critical size, mid-diaphyseal, stabilized defects in the femora of Fischer rats. Unlike control defects, those receiving gene-activated muscle underwent rapid healing, with evidence of radiologic bridging as early as 10 days after implantation and restoration of full mechanical strength by 8 weeks. Histologic analysis suggests that the grafts rapidly differentiated into cartilage, followed by efficient endochondral ossification. Fluorescence in situ hybridization detection of Y-chromosomes following the transfer of male donor muscle into female rats demonstrated that at least some of the osteoblasts of the healed bone were derived from donor muscle. Gene activated fat also healed critical sized defects, but less quickly than muscle and with more variability. Anti-adenovirus antibodies were not detected. Pilot studies in a rabbit osteochondral defect model demonstrated the promise of this technology for healing cartilage defects. Further development of these methods should provide ways to heal bone and cartilage more expeditiously, and at lower cost, than is presently possible.

Current opportunities and challenges in skeletal muscle tissue engineering

The purpose of this article is to give a concise review of the current state of the art in tissue engineering (TE) of skeletal muscle and the opportunities and challenges for future clinical applicability. The endogenous progenitor cells of skeletal muscle, i.e. satellite cells, show a high proneness to muscular differentiation, in particular exhibiting the same characteristics and function as its donor muscle. This suggests that it is important to use an appropriate progenitor cell, especially in TE facial muscles, which have a exceptional anatomical and fibre composition compared to other skeletal muscle. Muscle TE requires an instructive scaffold for structural support and to regulate the proliferation and differentiation of muscle progenitor cells. Current literature suggests that optimal scaffolding could comprise of a fibrin gel and cultured monolayers of muscle satellite cells obtained through the cell sheet technique. Tissue-engineered muscle constructs require an adequate connection to the vascular system for efficient transport of oxygen, carbon dioxide, nutrients and waste products. Finally, functional and clinically applicable muscle constructs depend on adequate neuromuscular junctions with neural cells. To reach this, it seems important to apply optimal electrical, chemotropic and mechanical stimulation during engineering and discover other factors that influence its formation. Thus, in addition to approaches for myogenesis, we discuss the current status of strategies for angiogenesis and neurogenesis of TE muscle constructs and the significance for future clinical use.

Secondary Procedures for Elbow Flexion Restoration in Late Obstetric Brachial Plexus Palsy

Even though total absence of elbow flexion in obstetric brachial plexus palsy (OBPP) is rare, weakness is a frequent problem. Numerous procedures for elbow flexion restoration in late obstetric brachial plexus palsy have been described. In this study, children with OBPP who underwent secondary reconstruction for elbow flexion restoration were studied. A retrospective review of 15 patients (16 elbows) who underwent 16 pedicled and eight free-muscle transfers for elbow flexion restoration was conducted. The mean follow-up period was 8.4 ± 2.9years (range, 25months to 12.2years). The mean age at operation (elbow surgery) was 5.4 ± 1.9years. The total arc of elbow motion was the result of the active elbow flexion less the flexion contracture. There was significant improvement in biceps muscle power from an average grading of 2.49 ± 0.80 preoperatively to 3.64 ± 0.46 postoperatively (p < 0.001). Thirteen of 16 elbows (81%) achieved good and excellent results (≥M3+); and three elbows (19%) fair results (M3- or M3). The average arc of motion was significantly improved from 36° ± 25° preoperatively to 94° ± 26° postoperatively (p < 0.001). The preoperative and postoperative average elbow flexion contracture was 10.9° ± 8.9° and 20° ± 12.2°, respectively. Pedicled and/or free-muscle transfers can significantly improve elbow flexion in late obstetric brachial plexus palsy. Choice of the procedure should be individualized and determined on the basis of the type of paralysis, availability of donor muscles, previous reconstruction, and experience of the surgeon.

The Utilization of Teres Major Muscle in Facial Paralysis Reanimation

This study explores vascular and morphologic anatomy of the teres major muscle, which can be an alternative to donor muscles used in functional muscle transfer in long-standing facial paralysis reanimation. A total of 14 teres major muscles from 7 embalmed cadavers were dissected and examined. Diameters and lengths of major and minor arteries supplying the muscle, venous pedicle diameter, neural pedicle diameter and length, their entrances into the muscle, the extendibility of neurovascular pedicles, when necessary, and the morphology of muscle were evaluated. Mean results obtained for teres major muscle in the study were as follows: the longest distance between the starting point and the area where the tendon started was 17.1 +/- 0.34 cm (range, 14.5-18.8 cm), the distance between the widest points was 5.8 +/- 0.5 cm (range, 5.1-6.2 cm), the thickest area was 3.4 +/- 0.9 cm (range, 2.8-3.9 cm), and surface area was 58.2 +/- 1.02 cm2 (range, 48.1-62.7 cm2). The major pedicle of the muscle, which is type 2 according to Mahtnes-Nahai classification, has a length of 3.0 +/- 0.6 cm (range, 2.4-3.6 cm) and a diameter of 2.7 +/- 0.21 mm (range, 1.85-3.4 mm). The nerve that provides motor innervation to the muscle is 5.9 cm (range, 4.1-9.9 cm) in length and 1.7 mm (range, 1.2-2.5 mm) in diameter. As a result of this preliminary study, we think that morphologic and neurovascular structures of this muscle is suitable for use in long-standing facial paralysis reanimation.

Management of Total Paralysis of the Brachial Plexus by the Double Free-muscle Transfer Technique

The double free-muscle transfer technique achieved a dramatic revolution in the treatment of total paralysis of the brachial plexus by providing universal prehensile function, although several requirements such as successful free-muscle transfers, stability of the proximal joints and prolonged postoperative rehabilitation are necessary for the success of this procedure. To obtain the best outcome of double free-muscle transfer, it is imperative to understand the key factors, viz. selection of the donor muscle, meticulous microsurgical technique, importance of proximal joint stability, selection of the kind of grip and postoperative rehabilitation. Double free-muscle transfer is not a simple microsurgical muscle transfer for finger movement, but a universal reconstructive procedure for total paralysis of the upper limb.

Intrinsic Laryngeal Muscle Reinnervation Using the Muscle-Nerve-Muscle Technique

This study was performed to investigate the muscle-nerve-muscle reinnervation technique in the larynx, in which a nerve conduit implanted into an innervated muscle conducts axonal sprouting into a denervated muscle while maintaining function of the donor muscle. In this study, the muscle-nerve-muscle technique was used to direct superior laryngeal nerve axons to reinnervate intrinsic laryngeal muscles by implanting the recurrent laryngeal nerve stump into the cricothyroid muscle in 8 dogs. In 4 of the dogs, the recurrent laryngeal nerve trunk to the adductor muscles was divided so that all axonal sprouting was directed to the posterior cricoarytenoid muscle. Six-month electromyography data were obtained from 6 of the 8 dogs. All 6 dogs showed evidence of successful reinnervation of the thyroarytenoid or posterior cricoarytenoid muscles with action potentials that corresponded to spontaneous respiratory efforts, while the donor cricothyroid muscles retained their phasic contraction. These responses were obliterated when the recurrent laryngeal nerve conduit was divided. Histologic examination of the intrinsic laryngeal muscles demonstrated successful reinnervation. The results confirm that intrinsic laryngeal muscles may be successfully reinnervated by the superior laryngeal nerve with the muscle-nerve-muscle technique, without sacrifice of function of the cricothyroid muscle. This method offers an alternative source of appropriately firing axons for laryngeal reinnervation procedures.

MyBP-C phosphorylation in donor, failing and HOCM human heart muscle

MyBP-C phosphorylation in donor, failing and HOCM human heart muscle

A Comparative Anatomical Study of Brachioradialis and Flexor Carpi Ulnaris Muscles: Implications for Total Tongue Reconstruction

Total or subtotal glossectomy following resection of intraoral tumors causes significant morbidity. Recent surgical endeavors have focused on the creation of a neotongue with both sensory and motor innervation. Although various local or regional free flaps have been used for this purpose, the optimal donor site remains undecided. The authors compared the neurovascular anatomy of the brachioradialis and flexor carpi ulnaris to assess their suitability as donor muscles together with overlying skin for functional total or subtotal tongue reconstruction. Eighty-eight brachioradialis and 80 flexor carpi ulnaris muscles were studied, comprising 120 dissected specimens, 18 arterial studies, two venous studies, 20 histologic studies, and eight neurovascular studies. The dominant vascular pattern of the brachioradialis varied. The major pedicle arose from the radial (38 percent), radial recurrent (42 percent), and brachial arteries (20 percent). The muscle also lacked a single neurovascular pedicle. The vasculature of the flexor carpi ulnaris was consistent. The ulnar artery supplied the dominant pedicle in 86 percent of cases. The entry point of motor innervation is near that of the vascular pedicles. A minor distal nerve accompanied the main vascular pedicle in 65 percent of cases. The overlying skin was supplied by musculocutaneous perforators. The lower lateral cutaneous nerve of the arm supplied the skin over the brachioradialis, and the medial cutaneous nerves of the arm and forearm provided sensation over the flexor carpi ulnaris. The authors delineated the anatomical advantages of the flexor carpi ulnaris over the brachioradialis for total or subtotal tongue reconstruction.

Nervale und muskuläre Ersatzoperationen zur Wiederherstellung der gelähmten Ellenbogenfunktion

Paralysis of elbow flexion or extension leads to major impairment of upper extremity function. Surgical reconstruction can be achieved using several procedures. If the time interval since the nerve injury is short, anatomic reconstruction by means of nerve suture or nerve transplantation should be attempted. Alternatively, nerve transposition is possible. If more than 12-18 months have elapsed, reinnervation of arm muscles can no longer be expected. In this case, muscle transposition is helpful. Restoring flexion is predominantly required following brachial plexus injury, when the function of the biceps, brachioradialis and brachialis muscles are lost. As donor muscles the latissimus dorsi, pectoralis major and triceps brachii can be used, alternatively a transfer of the flexor-pronator muscles of the forearm is possible. Latissimus dorsi transfer to reconstruct elbow flexion is also indicated in defects of the anterior upper arm muscle compartiment due to trauma, ischemia, or tumor. Patients with proximal radial nerve lesions may benefit from latissimus transfer to reachieve elbow flexion extension. In tetraplegic patients, elbow extension is restored mainly by transfer of the posterior deltoid muscle extended with a tendon graft, or by means of a biceps-to-triceps transfer.

Use of a novel collagen matrix with oriented pore structure for muscle cell differentiation in cell culture and in grafts

Tissue engineering of skeletal muscle from cultured cells has been attempted using a variety of synthetic and natural macromolecular scaffolds. Our study describes the application of artificial scaffolds (collagen sponges, CS) consisting of collagen-I with parallel pores (width 20–50 μm) using the permanent myogenic cell line C2C12. CS were infiltrated with a high-density cell suspension, incubated in medium for proliferation of myoblasts prior to further culture in fusion medium to induce differentiation and formation of multinucleated myotubes. This resulted in a parallel arrangement of myotubes within the pore structures. CS with either proliferating cells or with myotubes were grafted into the beds of excised anterior tibial muscles of immunodeficient host mice. The recipient mice were transgenic for enhanced green fluorescent protein (eGFP) to determine a host contribution to the regenerated muscle tissue. Histological analysis 14–50 days after surgery showed that donor muscle fibres had formed in situ with host contributions in the outer portions of the regenerates. The function of the regenerates was assessed by direct electrical stimulation which resulted in the generation of mechanical force. Our study demonstrated that biodegradable CS with parallel pores support the formation of oriented muscle fibres and are compatible with force generation in regenerated muscle.

Functional gracilis flap in thenar reconstruction

Restoration of lost opposition in the context of significant thenar soft tissue defects represents a tremendous reconstructive challenge. Free functioning muscle transfer has been described in this context and has the advantage of providing both a functioning muscle unit as well as soft tissue coverage in a single reconstructive procedure. It adds to the injured limb, and by sparing donor tendons avoids the need for re-education of motor function. We describe the use of a free innervated gracilis muscle flap for functional thenar reconstruction in two unique cases following extensive traumatic loss of thenar skin and musculature. Crucially, in each case, the recurrent motor branch of the median nerve had been destroyed at its point of insertion into the thenar muscle remnants. To date, the main reported disadvantages of free functioning muscle transfer in thenar reconstruction include difficult flap dissections, donor site morbidity, inadequate strength and excursion of the transplanted muscle and excessively bulky flaps. Our aim was, as far as possible, to address these issues. Each thenar defect was measured and a corresponding segment of gracilis muscle, measured in situ, was raised on the proximal neurovascular pedicle. End-side microvascular anastomosis was performed between the medial circumflex femoral artery and the radial artery. The venae comitantes of the pedicle were anastomosed end-end with those of the radial artery and also with the cephalic vein. Epineural anastomosis was performed between the motor branch of the obturator nerve and the recurrent motor branch of the median nerve. Each flap was covered with a split thickness skin graft. Both flaps survived without any complication. Both patients regained excellent voluntary thumb opposition, sufficient to allow return to full-time employment, and had restoration of sufficient thenar bulk. This was achieved with minimal donor site morbidity. Restoration of lost opposition, in the context of significant thenar soft tissue defects, can be achieved using a free functional gracilis flap. This produces clinically excellent functional results and can be carried out as a single stage reconstructive procedure. This is a novel application of a tremendously versatile donor muscle in functioning free muscle transfer.

Fusogenic lipid vesicles loaded with adenosine triphosphate (ATP) deliver energy to rat skeletal muscle

In rat transplant studies, donor hindlimbs (HLs) perfused with a solution containing fusogenic lipid vesicles loaded with ATP (FLVs-ATP) remained viable after 13h of warm ischemia and transplantation. Histological analysis of donor muscles 7 days post-op revealed that myocytes were regenerating. It was not clear whether FLVs-ATP were delivering ATP to skeletal muscle. The purpose of this study was to determine whether HLs perfused with FLVs-ATP delivered ATP to myocytes. We hypothesized that if FLVs-ATP delivered ATP intracellularly the hydrolysis rate of phosphocreatine (PCr) would be prolonged in treated muscles. To test this hypothesis phosphate spectra from HL muscles were analyzed using 31Phosphate Nuclear Magnetic Resonance (31P NMR). Rat HLs were allocated into 6 groups (n=10/group) and perfused with one of the following solutions: Heparinized Lactated Ringer’s (HLR); ATP only 5mM and 10mM; empty FLVs (no ATP); FLVs-ATP 10mM and 20mM. 31P NMR spectra were recorded for 3 h, and PCr half-life was calculated using peak intensity values. The PCr half-life of muscles treated with FLVs-ATP 20mM (16.9 ±0.7 min) and ATP 10mM (18.2 ±0.8 min) was significant (p<0.05) when compared to both HLR (13.7 ±0.8 min) and empty FLVs (6.1±2.2 min). Means for HLR and empty FLVs were significantly different (p<0.05). We conclude that both FLVs-ATP and free ATP had a PCr sparing effect, however, the mechanisms are not clear.

Flexor Pollicis Brevis Adductorplasty

Loss of pinch power associated with loss of coordinated movement of thumb and index fingers is the major disability in patients with ulnar nerve paralysis. Several tendon transfer methods utilizing different donor muscles have been used to restore adductor pollicis muscle function in ulnar nerve paralysis. In this paper, we discuss the transfer of flexor digitorum brevis muscle to the tendon of adductor pollicis muscle as an alternative method to restore key pinch in ulnar nerve paralysis. The technique was applied to 4 patients with ulnar nerve paralysis. Before clinical application, an anatomic study was carried out in 6 cadaver hands. In cadavers, radial and ulnar arteries were injected with latex and arterial pedicles of flexor pollicis brevis muscle were dissected under 4x magnification. Also, motor branches from the median nerve were shown at the entrance point to the muscle. In surgical practice, the superficial head of the muscle is detached from its insertion and the minor pedicle of the muscle is cut. Muscle is dissected proximally up to two thirds of its length. The dominant pedicle of the muscle originating from superficial palmar arcus is preserved, and the muscle is sutured to the tendon of the adductor pollicis muscle close to its insertion. Patients were evaluated in terms of key pinch strength preoperatively and at the postoperative sixth month using a pinch meter (Chattanooga Group, Inc). Key pinch strengths were recorded and expressed as percentage of the strength of the contralateral uninvolved hand. Mean key pinch strength of our patients was 29.7%. In conclusion, we believe in that flexor pollicis brevis adductorplasty may be an alternative method for restoration of adductor pollicis muscle function in ulnar nerve paralysis.