A PRISMA-IPD systematic review and meta-analysis: does age and follow-up improve active range of motion of the wrist and forearm following pediatric upper extremity cerebral palsy surgery?

Purpose: Surgical treatments such as tendon transfers and muscle lengthening play a significant role in cerebral palsy management,but timing of upper extremity cerebral palsy surgery remains controversial. This study systematically reviews the current literature and investigates the correlation between age at surgery and follow-up time with surgical outcomes in pediatric upper extremity cerebral palsy patients. Methods: A comprehensive search of PubMed, Cochrane, Web of Science, and CINAHL databases was performed from inception to July 2020 and articles were screened using PRISMA guidelines to include full-text, English papers. Data analysis was performed using itemized data points for age at surgery, follow-up length, and surgery outcomes, reported as changes in active forearm and wrist motion. A 3D linear model was performed, to analyze the relationship between age, follow-up length, and surgery outcomes. Results: A total of 3,855 papers were identified using the search terms and a total of 8 studies with itemized patient data (n=126) were included in the study. The studies overall possessed moderate bias according to the ROBINS-I scale. Regression analysis showed that age is a significant predictor of change (|t| > 2) in active forearm supination (Estimate = -2.3465, Std. Error = 1.0938, t-value= -2.145) and wrist flexion (Estimate = -2.8474, Std. Error = 1.0771, t-value = -2.643) post-intervention, with older individuals showing lesser improvements. The duration of follow-up is a significant predictor of improvement in forearm supination (Estimate = 0.3664, Std. Error = 0.1797, t-value = 2.039) and wrist extension (Estimate = 0.7747, Std. Error = 0.2750, t-value = 2.817). In contrast, forearm pronation (Estimate = -0.23756, Std. Error = 0.09648, t-value = -2.462) and wrist flexion (Estimate = -0.4243, Std. Error=0.1859, t-value = -2.282) have a significant negative association with follow-up time. Conclusion: These results suggest that there is significant correlation between the age and follow up after surgery with range of motion gains. Most notably, increased age at surgery had a significant negative correlation with select active range of motion postoperative outcomes. Future research should focus on identifying other factors that could affect results of surgical treatment in upper extremity.

Intercostal Nerve Transfer for Biceps Reinnervation in Obstetrical Brachial Plexus Palsy: A Preferred Reporting Items for Systematic Reviews and Meta-Analysis for Individual Patient Data Systematic Review using Individualized Fusion and Comparison to Supraclavicular Exploration and Nerve Grafting.

Introduction: The objective of this study was to search existing literature on nerve reconstruction surgery in patients with obstetric brachial plexus palsy to determine whether treatment with supraclavicular exploration and nerve grafting produced better elbow flexion outcomes compared to intercostal nerve transfer. Methods: This study was a systematic review following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis for Individual Patient Data guidelines. A systematic search was conducted using multiple databases. An ordinal regression model was used to analyze the effect of using supraclavicular exploration and nerve grafting or intercostal nerve on elbow flexion with the two scores measured: elbow flexion Medical Research Council scores and Toronto active movements scale scores for elbow flexion. Results: A final patient database from 6 published articles consisted of 83 supraclavicular exploration and nerve grafting patients (73 patients with Medical Research Council and 10 patients with Toronto score) and 7 published articles which consisted of 131 intercostal nerve patients (84 patients with Medical Research Council and 47 patients with Toronto scores). Patients who underwent supraclavicular exploration and nerve grafting presented with an average Medical Research Council score of 3.9 ± 0.72 and an average Toronto score of 6.2 ± 2.2. Patients who underwent intercostal nerve transfer presented with an average Medical Research Council score of 3.9 ± 0.71 and an average Toronto score of 6.4 ± 1.2. There was no statistical difference between supraclavicular exploration and nerve grafting and intercostal nerve transfer when utilizing Medical Research Council elbow flexion scores (ordinal regression: 0.3821, standard error: 0.4590, p = 0.2551) or Toronto Active Movement Scale score for elbow flexion (ordinal regression: 0.7154, standard error: 0.8487, p = 0.2188). Conclusion: Regardless of surgical intervention utilized (supraclavicular exploration and nerve grafting or intercostal nerve transfers), patients had excellent outcomes for elbow flexion following obstetric brachial plexus palsy when utilizing Medical Research Council or Toronto scores for elbow flexion. The difference between these scores was not statistically significant. Type of study/Level of evidence: Therapeutic Study: Investigating the Result of Treatment/level III.

Forearm and elbow secondary surgical procedures in neonatal brachial plexus palsy: a systematic scoping review.

Background: Neonatal Brachial plexus palsy is an injury during delivery that can lead to loss of motor function and limited range of motion in patients due to damage of nerves in the brachial plexus. This scoping review aims to explore types of procedures performed and assess outcomes of forearm and elbow secondary surgery in pediatric patients. Methods: Searches of PubMed, Cochrane, Cumulative Index to Nursing and Allied Health Literature, Web of Sciences, and Scopus were completed to obtain studies describing surgical treatment of elbow and forearm in pediatric patients with neonatal Brachial plexus palsy. 865 abstracts and titles were screened by two independent reviewers resulting in 295 full text papers; after applying of inclusion and exclusion criteria 18 articles were included. The level of evidence of this study is level IV. Results: Ten main procedures were performed to regain function of the forearm and elbow in neonatal brachial plexus birth palsy patients. Procedures had different aims, with supination contracture (6) and elbow flexion restoration (5) being the most prevalent. The variance between preoperative and postoperative soft tissue and bony procedures outcomes decreased and showed improvement with respect to the aim of each procedure category. For soft tissue procedures, a statistically significant increase was found between preoperative and postoperative values for active elbow flexion, passive supination, and active supination. For bony procedures, there was a statistically significant decrease between preoperative and postoperative values of passive and active supination. Conclusion: Overall, all procedures completed in the assessed articles of this study were successful in their aim. Bony procedures, specifically osteotomies, were found to have a wider range of results, whereas soft tissue procedures were found to be more consistent and reproducible with respect to their outcomes. Bony and soft tissue procedures were found vary in their aims and outcomes. This study indicates the need for further research to augment knowledge about indications and long-term benefits to each procedure.

Rehabilitation protocols in neonates undergoing primary nerve surgery for upper brachial plexus palsy: A scoping review.

INTRODUCTION: Surgical management is recommended in patients with severe neonatal brachial plexus palsy (NBPP) within the first 6 months of age to regain best possible function. Rehabilitation post-surgery remains relatively unexplored. This is a scoping review that explores, which rehabilitation modalities exist and how they vary for different microsurgical approaches in NBPP. MATERIALS AND METHODS: A systematic search was conducted to include articles about upper trunk obstetric brachial plexus nerve microsurgery in pediatric patients that made mention of rehabilitation protocols. The aims of rehabilitation modalities varied and were grouped: "passive" movement to prevent joint contracture or stiffness, "active" or task-oriented movement to improve motor function, or "providing initial motor recovery". Surgical approach was described as either exploration of the brachial plexus (EBP) or nerve transfer without root exploration (NTwoRE). Technique was categorized into transfers and non-transfers. RESULTS: Thirty-six full-text articles were included. Initiation of rehabilitation was 22.26 days post-surgery. Twenty-eight studies were EBP, and six were NTwoRE. Of studies classifiable by aims, nine were "passive", nine were "active", and five were "providing initial motor recovery". Only 27.7% of EBP studies mentioned active therapy, while 75.0% of NTwoRE studies mentioned active therapy. The average age of patients in the EBP procedure category was 7.70 months, and NTwoRE was 17.76 months. Within transfers, the spinal accessory to suprascapular group was more likely to describe an active shoulder exercise therapy, whereas contralateral C7 group was more likely to describe "initial motor recovery", especially through the use of electrostimulation. All articles on electrostimulation recommended 15-20-minute daily treatment. CONCLUSION: Information on rehabilitation is limited post-nerve surgery in NBPP. However, when mentioned, the aims of these therapies vary with respect to surgical approach and technique. The type of therapy to employ may be a multifaceted decision, involving factors such as patient age, initial deformity, and goals of the care team.

Educational quality of YouTube content on brachial plexus injury and treatment.

INTRODUCTION: While surgical literature exists on birth-related brachial plexus injury (BPI), there are not validated sources of information on BPI for patients, which can impact patient autonomy and decision-making. With YouTube as a popular source for patients to research diagnoses, this study aims to evaluate the quality of information regarding BPI and its treatment available on the platform. MATERIALS AND METHODS: BPI YouTube videos were screened independently by two reviewers. Videos were categorized by source: (1) academic, government, and non-profit organizations; (2) private practices, companies, and for-profit organizations; (3) independent users. Each video was evaluated for reliability, credibility, and quality using the modified DISCERN criteria (scale, 0-5), Journal of the American Medical Association (JAMA) criteria (scale, 0-4), and Global Quality Scale (GQS; scale, 1-5). Surgical treatment videos were analyzed by the senior author using a modified "treatment" DISCERN criteria (scale, 8-40). Non-English videos were excluded from this study. Analysis of variance tests were used to compare means. RESULTS: One hundred and fifteen videos were selected for final analysis. The mean modified DISCERN score was 3.26; JAMA was 2.31; GQS was 3.48. Videos were subdivided according to source. Group 1, 2, and 3 had 45, 24, and 46 videos, respectively. Modified DISCERN score was greater for Group 1 than Group 2 (3.58 vs. 3.04, p < .001) and Group 3 (3.58 vs. 3.07, p < .001). JAMA score was greater for Group 1 than Group 2 (2.63 vs 2.15, p = .041) and Group 3 (2.63 vs. 2.08, p = .002). GQS score was greater for Group 1 than Group 2 (3.93 vs. 3.31, p = .031) and Group 3 (3.93 vs. 3.13, p < .001). Of the 34 videos (44.7%) that mentioned treatment, the DISCERN score was 14.32. CONCLUSION: The videos analyzed were found to have moderate reliability, credibility, and quality. The reliability of information regarding treatments for BPI was poor. Healthcare providers should supply additional information on treatment of BPI.

Magnetic resonance imaging for diagnosis of suspected neurogenic thoracic outlet syndrome-a systematic scoping review.

Background: Neurogenic Thoracic Outlet Syndrome (nTOS) is a rare pathology caused by dynamic conditions or compression of neurovascular structures in the thoracic outlet region. nTOS can be difficult to diagnose due to nonspecific symptoms and magnetic resonance imaging (MRI) techniques are increasingly used to aid the diagnosis and surgical planning. This scoping systematic review explores how MRI is used for diagnosing nTOS and summarizes details of published MRI protocols. Methods: A systematic screening of PubMed, Cochrane, Web of Science, and CINAHL databases using PRISMA-IPD guidelines was conducted in September 2022 to include full-text English papers on MRI and nTOS. Inclusion criteria involved studies describing MRI protocols for the diagnosis of TOS, with a focus on the imaging sequences and protocols. Results: 6289 papers were screened to include 28 papers containing details of MRI protocols. The details of MRI protocols in the analyzed articles were incomplete in all studies. Most authors used 1.5T systems and included T1 and T2-weighted sequences. Most studies applied fat suppression, mainly with STIR. Positioning of the arm differed between studies, including neutral, hyperabducted and abducted and externally rotated positions. Conclusion: Our review highlights a prevalent lack of detailed MRI protocol documentation for brachial plexus. Authors primarily rely on conventional 1.5T systems, employing standard T1 and T2-weighted sequences. The adoption of novel MRI sequences is notably lacking, and fat suppression techniques predominantly adhere to older methods as STIR. There is a clear imperative for authors to provide more comprehensive reporting of the MRI protocols utilized in their studies, ultimately enhancing comparability and clinical applicability. Establishing clear protocol reporting guidelines is crucial to allow for comparison between studies.

Outcomes of humeral osteotomies versus soft-tissue procedures in secondary surgical procedures for neonatal brachial plexus palsy: a meta-analysis.

Secondary surgical procedures can be used in brachial plexus birth injury to correct shoulder movement imbalances. This study compares outcomes of the two secondary surgical procedure types: humeral osteotomies and soft tissue procedures. Outcome measures assessed included active and passive internal and external rotation, active and passive abduction and adduction, active and passive flexion and extension, percentage of the humeral head anterior to the middle glenoid fossa, glenoid version, and Mallet Score. Nineteen full-text articles were included in the analysis. Humeral osteotomies resulted in a loss of internal rotation postoperatively (-15.94°). Active internal rotation was not evaluated for soft tissue procedures. All other assessed outcomes were improved postoperatively for bony and soft tissue procedures. Bony procedures exhibited a greater degree of active external rotation postoperatively when compared to soft tissue procedures (+67° vs. +40°). Both bony and soft tissue procedures Improve shoulder function in children with neonatal brachial plexus palsy, however, soft tissue procedures showed greater consistency in outcomes. Level of Evidence: IV.

When theory meets reality- a mismatch in communication: a qualitative study of clinical transition from communication skills training to the surgical ward.

BACKGROUND: Communication skills training in patient centered communication is an integral part of the medical undergraduate education and has been shown to improve various components of communication. While the effects of different educational interventions have been investigated, little is known about the transfer from theoretical settings to clinical practice in the context of communication skills courses not integrated in the clinical curriculum. Most studies focus on single factors affecting transfer without considering the comprehensive perspective of the students themselves. The aim of this study is to explore how the students experience the transition to clinical practice and what they perceive as challenges in using patient centered communication. METHODS: Fifteen 4th year medical students were interviewed 3 weeks after the transition from an advanced communication skills course to surgical internship using semi-structured interviews. Qualitative content analysis was used to analyze the interviews. RESULTS: The analysis resulted in a theme 'When theory meets reality- a mismatch in communication'. It was comprised of four categories that encompassed the transfer process, from theoretical education, practical communication training and surgical internship to students' wishes and perceived needs. CONCLUSIONS: We concluded that preparing the students through theoretical and practical training should reflect the reality they will face when entering clinical practice. When educating medical students as a group, their proclivity for perfectionism, high performance environment and achievement-related stress should be taken into consideration. The role of tutors being role models, offering guidance, giving feedback and providing support plays a major part in facilitating transfer of communication skills. To enable transfer to a larger extent, the environment needs to promote patient centeredness and students need more opportunities to practice communication with their patients.

Trends of Age and Geographical Location in Microsurgical Treatment of Obstetric Brachial Plexus Palsy.

BACKGROUND: Debate over the optimal age at time of surgery for treatment of brachial plexus birth injury (BPBI) remains controversial, and there exists geographical varia- tion in surgical preference for age at time of surgery. The objective of this review was to analyze trends in age and geography in brachial plexus microsurgery for treatment of brachial plexus birth injury (BPBI) over time. METHODS: Review of the literature in this study was con- ducted according to the Preferred Reporting Items for Sys- tematic Reviews and Meta-Analysis (PRISMA) guidelines. PubMed, Cochrane, Web of Science, and the Cumulative Index to Nursing and Allied Health Literature (CINAHL) databases were searched. RESULTS: Pediatric patients undergoing brachial plexus microsurgery described in published reports before 2011 had a mean of 7.15 ± 6.56 months of age, while pediatric patients undergoing brachial plexus microsurgery surgery described in published reports after 2011 had a mean of 11.23 ± 9.76 months of age (p < 0.05). The mean age at surgery was lower in publications from Asian countries (6.29 months) than in publications from North America (11.34 months; p < 0.05). CONCLUSIONS: Age at time of microsurgery for treatment of BPBI is increasing, with mean age at surgeries occurring in and after 2011 being 4 months higher than thos occuring before 2011. The mean age at surgery was about 5 months higher in North American publications than in Asian pub- lications.

Magnetic resonance imaging of the brachial plexus. Part 2: Traumatic injuries.

The most common indications for magnetic resonance imaging (MRI) of the brachial plexus (BP) are traumatic injuries. The role of MRI of the BP has increased because of recent trends favoring earlier surgery. Determining preganglionic vs. postganglionic injury is essential, as different treatment strategies are required. Thus, MRI of the BP should be supplemented with cervical spine MRI to assess the intradural part of the spinal nerves, including highly T2-weighted techniques. Acute preganglionic injuries usually manifest as various combinations of post-traumatic pseudomeningocele, the absence of roots, deformity of nerve root sleeves, displacement of the spinal cord, hemorrhage in the spinal canal, presence of scars in the spinal canal, denervation of the back muscles, and syrinx. Spinal nerve root absence is more specific than pseudomeningocele on MRI. Acute postganglionic injuries can present as lesions in continuity or tears. The following signs indicate injury to the BP: side-to-side difference, swelling, partial, or total BP rupture. Injury patterns and localization are associated with the mechanism of trauma, which implies a significant role for MRI in the work-up of patients. The identification and description of traumatic lesions involving the brachial plexus need to be systematic and detailed. Using an appropriate MRI protocol, obtaining details about the injury, applying a systematic anatomical approach, and correlating imaging findings to relevant clinical data to make a correct diagnosis. Information about the presence or suspicion of root avulsion should always be provided.

Surgical timing in neonatal brachial plexus palsy: A PRISMA-IPD systematic review.

BACKGROUND: Neonatal brachial plexus palsy (NBPP) is a serious complication of high-risk deliveries with controversy surrounding timing of corrective nerve surgery. This review systematically examines the existing literature and investigates correlations between age at time of upper trunk brachial plexus microsurgery and surgical outcomes. METHODS: A systematic screening of PubMed, Cochrane, Web of Science, and CINAHL databases using PRISMA-IPD guidelines was conducted in January 2020 to include full-text English papers with microsurgery in upper trunk palsy, pediatric patients. Spearman rank correlation analysis and two-tailed t-tests were performed using individual patient data to determine the relationship between mean age at time of surgery and outcome as determined by the Mallet, Medical Research Council (MRC), or Active Movement Scale (AMS) subscores. RESULTS: Two thousand nine hundred thirty six papers were screened to finalize 25 papers containing individual patient data (n = 256) with low to moderate risk of bias, as assessed by the ROBINS-I assessment tool. Mallet subscore for hand-to-mouth and shoulder abduction, AMS subscore for elbow flexion and external rotation, and MRC subscore for elbow flexion were analyzed alongside the respective age of patients at surgery. Spearman rank correlation analysis revealed a significant negative correlation (ρ = -0.30, p < .01, n = 89) between increasing age (5.50 ± 2.09 months) and Mallet subscore for hand-to-mouth (3.43 ± 0.83). T-tests revealed a significant decrease in Mallet hand-to-mouth subscores after 6 months (p < .05) and 9 months (p < .05) of age. No significant effects were observed for Mallet shoulder abduction, MRC elbow flexion, or AMS elbow flexion and external rotation. CONCLUSION: The cumulative evidence suggests a significant negative correlation between age at microsurgery and Mallet subscores for hand-to-mouth. However, a similar correlation with age at surgery was not observed for Mallet shoulder abduction, MRC elbow flexion, AMS external rotation, and AMS elbow flexion subscores.

Motion Analytics of Trapezius Muscle Activity in an 18-Year-Old Female with Extended Upper Brachial Plexus Birth Palsy.

Background The trapezius muscle is often utilized as a muscle or nerve donor for repairing shoulder function in those with brachial plexus birth palsy (BPBP). To evaluate the native role of the trapezius in the affected limb, we demonstrate use of the Motion Browser, a novel visual analytics system to assess an adolescent with BPBP. Method An 18-year-old female with extended upper trunk (C5-6-7) BPBP underwent bilateral upper extremity three-dimensional motion analysis with Motion Browser. Surface electromyography (EMG) from eight muscles in each limb which was recorded during six upper extremity movements, distinguishing between upper trapezius (UT) and lower trapezius (LT). The Motion Browser calculated active range of motion (AROM), compiled the EMG data into measures of muscle activity, and displayed the results in charts. Results All movements, excluding shoulder abduction, had similar AROM in affected and unaffected limbs. In the unaffected limb, LT was more active in proximal movements of shoulder abduction, and shoulder external and internal rotations. In the affected limb, LT was more active in distal movements of forearm pronation and supination; UT was more active in shoulder abduction. Conclusion In this female with BPBP, Motion Browser demonstrated that the native LT in the affected limb contributed to distal movements. Her results suggest that sacrificing her trapezius as a muscle or nerve donor may affect her distal functionality. Clinicians should exercise caution when considering nerve transfers in children with BPBP and consider individualized assessment of functionality before pursuing surgery.

The Pathogenesis of Glenohumeral Deformity and Contracture Formation in Obstetric Brachial Plexus Palsy-A Review.

Contractures of the shoulder joint and glenohumeral joint dysplasia are well known complications to obstetrical brachial plexus palsy. Despite extensive description of these sequelae, the exact pathogenesis remains unknown. The prevailing theory to explain the contractures and glenohumeral joint dysplasia states that upper trunk injury leads to nonuniform muscle recovery and thus imbalance between internal and external rotators of the shoulder. More recently, another explanation has been proposed, hypothesizing that denervation leads to reduced growth of developing muscles and that reinnervation might suppress contracture formation. An understanding of the pathogenesis is desirable for development of effective prophylactic treatment. This article aims to describe the current state of knowledge regarding these important complications.

Effects of early nerve repair on experimental brachial plexus injury in neonatal rats.

Obstetrical brachial plexus injury refers to injury observed at the time of delivery, which may lead to major functional impairment in the upper limb. In this study, the neuroprotective effect of early nerve repair following complete brachial plexus injury in neonatal rats was examined. Brachial plexus injury induced 90% loss of spinal motoneurons and 70% decrease in biceps muscle weight at 28 days after injury. Retrograde degeneration in spinal cord was associated with decreased density of dendritic branches and presynaptic boutons and increased density of astrocytes and macrophages/microglial cells. Early repair of the injured brachial plexus significantly delayed retrograde degeneration of spinal motoneurons and reduced the degree of macrophage/microglial reaction but had no effect on muscle atrophy. The results demonstrate that early nerve repair of neonatal brachial plexus injury could promote survival of injured motoneurons and attenuate neuroinflammation in spinal cord.

Long-Term Effects of Fibrin Conduit with Human Mesenchymal Stem Cells and Immunosuppression after Peripheral Nerve Repair in a Xenogenic Model.

INTRODUCTION: Previously we showed that a fibrin glue conduit with human mesenchymal stem cells (hMSCs) and cyclosporine A (CsA) enhanced early nerve regeneration. In this study long term effects of this conduit are investigated. METHODS: In a rat model, the sciatic nerve was repaired with fibrin conduit containing fibrin matrix, fibrin conduit containing fibrin matrix with CsA treatment and fibrin conduit containing fibrin matrix with hMSCs and CsA treatment, and also with nerve graft as control. RESULTS: At 12 weeks 34% of motoneurons of the control group regenerated axons through the fibrin conduit. CsA treatment alone or with hMSCs resulted in axon regeneration of 67% and 64% motoneurons respectively. The gastrocnemius muscle weight was reduced in the conduit with fibrin matrix. The treatment with CsA or CsA with hMSCs induced recovery of the muscle weight and size of fast type fibers towards the levels of the nerve graft group. DISCUSSION: The transplantation of hMSCs for peripheral nerve injury should be optimized to demonstrate their beneficial effects. The CsA may have its own effect on nerve regeneration.

Proximal versus Distal Nerve Transfer for Biceps Reinnervation-A Comparative Study in a Rat's Brachial Plexus Injury Model.

BACKGROUND: The exact role of proximal and distal nerve transfers in reconstruction strategies of brachial plexus injury remains controversial. We compared proximal with distal nerve reconstruction strategies in a rat model of brachial plexus injury. METHODS: In rats, the C6 spinal nerve with a nerve graft (proximal nerve transfer model, n = 30, group A) and 50% of ulnar nerve (distal nerve transfer model, n = 30, group B) were used as the donor nerves. The targets were the musculocutaneous nerve and the biceps muscle. Outcomes were recorded at 4, 8, 12, and 16 weeks postoperatively. Outcome parameters included grooming test, biceps muscle weight, compound muscle action potentials, tetanic contraction force, and axonal morphology of the donor and target nerves. RESULTS: The axonal morphology of the 2 donor nerves revealed no significant difference. Time interval analysis in the proximal nerve transfer group showed peak axon counts at 12 weeks and a trend of improvement in all functional and physiologic parameters across all time points with statistically significant differences for grooming test, biceps compound action potentials, tetanic muscle contraction force, and muscle weight at 16 weeks. In contrast, in the distal nerve transfer group, the only statistically significant difference was observed between the 4 and 8 week time points, followed by a plateau from 8 to 16 weeks. CONCLUSIONS: Outcomes of proximal nerve transfers are ultimately superior to distal nerve transfers in our experimental model. Possible explanations for the superior results include a reduced need for cortical adaptation and higher proportions of motor units in the proximal nerve transfers.

A Simplified Lateral Hinge Approach to the Proximal Interphalangeal Joint.

Proximal interphalangeal joint replacement is an effective treatment for painful arthritis affecting the joint. However, the complication rate is relatively high, with many of these complications related to soft-tissue imbalance or instability. Volar, dorsal, and lateral approaches have all been described with varying results. We describe a new simplified lateral hinge approach that splits the collateral ligament to provide adequate exposure of the joint. Following insertion of the prosthesis the collateral ligament is simply repaired, side-to-side, which stabilizes the joint. As the central slip, opposite collateral ligament, flexor and extensor tendons have not been violated, early active mobilization without splinting is possible, and the risk of instability, swan-neck, and boutonniere deformity are reduced. The indications, contraindications, surgical technique, and rehabilitation protocol are described.

Effect of delayed peripheral nerve repair on nerve regeneration, Schwann cell function and target muscle recovery.

Despite advances in surgical techniques for peripheral nerve repair, functional restitution remains incomplete. The timing of surgery is one factor influencing the extent of recovery but it is not yet clearly defined how long a delay may be tolerated before repair becomes futile. In this study, rats underwent sciatic nerve transection before immediate (0) or 1, 3, or 6 months delayed repair with a nerve graft. Regeneration of spinal motoneurons, 13 weeks after nerve repair, was assessed using retrograde labeling. Nerve tissue was also collected from the proximal and distal stumps and from the nerve graft, together with the medial gastrocnemius (MG) muscles. A dramatic decline in the number of regenerating motoneurons and myelinated axons in the distal nerve stump was observed in the 3- and 6-months delayed groups. After 3 months delay, the axonal number in the proximal stump increased 2-3 folds, accompanied by a smaller axonal area. RT-PCR of distal nerve segments revealed a decline in Schwann cells (SC) markers, most notably in the 3 and 6 month delayed repair samples. There was also a progressive increase in fibrosis and proteoglycan scar markers in the distal nerve with increased delayed repair time. The yield of SC isolated from the distal nerve segments progressively fell with increased delay in repair time but cultured SC from all groups proliferated at similar rates. MG muscle at 3- and 6-months delay repair showed a significant decline in weight (61% and 27% compared with contra-lateral side). Muscle fiber atrophy and changes to neuromuscular junctions were observed with increased delayed repair time suggestive of progressively impaired reinnervation. This study demonstrates that one of the main limiting factors for nerve regeneration after delayed repair is the distal stump. The critical time point after which the outcome of regeneration becomes too poor appears to be 3-months.

Fibrin conduit supplemented with human mesenchymal stem cells and immunosuppressive treatment enhances regeneration after peripheral nerve injury.

To address the need for the development of bioengineered replacement of a nerve graft, a novel two component fibrin glue conduit was combined with human mesenchymal stem cells (MSC) and immunosupressive treatment with cyclosporine A. The effects of MSC on axonal regeneration in the conduit and reaction of activated macrophages were investigated using sciatic nerve injury model. A 10mm gap in the sciatic nerve of a rat was created and repaired either with fibrin glue conduit containing diluted fibrin matrix or fibrin glue conduit containing fibrin matrix with MSC at concentration of 80×10(6) cells/ml. Cells were labeled with PKH26 prior to transplantation. The animals received daily injections of cyclosporine A. After 3 weeks the distance of regeneration and area occupied by regenerating axons and ED1 positives macrophages was measured. MSC survived in the conduit and enhanced axonal regeneration only when transplantation was combined with cyclosporine A treatment. Moreover, addition of cyclosporine A to the conduits with transplanted MSC significantly reduced the ED1 macrophage reaction.

Muscle recovery after repair of short and long peripheral nerve gaps using fibrin conduits.

Peripheral nerve injuries with loss of nervous tissue are a significant clinical problem and are currently treated using autologous nerve transplants. To avoid the need for donor nerve, which results in additional morbidity such as loss of sensation and scarring, alternative bridging methods have been sought. Recently we showed that an artificial nerve conduit moulded from fibrin glue is biocompatible to nerve regeneration. In this present study, we have used the fibrin conduit or a nerve graft to bridge either a 10 mm or 20 mm sciatic nerve gap and analyzed the muscle recovery in adult rats after 16 weeks. The gastrocnemius muscle weights of the operated side were similar for both gap sizes when treated with nerve graft. In contrast, muscle weight was 48.32 ± 4.96% of the contra-lateral side for the 10 mm gap repaired with fibrin conduit but only 25.20 ± 2.50% for the 20 mm gap repaired with fibrin conduit. The morphology of the muscles in the nerve graft groups showed an intact, ordered structure, with the muscle fibers grouped in fascicles whereas the 20 mm nerve gap fibrin group had a more chaotic appearance. The mean area and diameter of fast type fibers in the 20 mm gap repaired with fibrin conduits were significantly (P<0.01) worse than those of the corresponding 10 mm gap group. In contrast, both gap sizes treated with nerve graft showed similar fiber size. Furthermore, the 10 mm gaps repaired with either nerve graft or fibrin conduit showed similar muscle fiber size. These results indicate that the fibrin conduit can effectively treat short nerve gaps but further modification such as the inclusion of regenerative cells may be required to attain the outcomes of nerve graft for long gaps.