Tumors of the Brachial Plexus: A Critical Analysis Review.

¼ Tumors of the brachial plexus are uncommon and can present as a mass, with or without neurological symptoms. At times, asymptomatic tumors are also picked up incidentally when imaging is performed for other reasons.¼ Magnetic resonance imaging is the main imaging modality used to evaluate tumors of the brachial plexus. Other imaging modalities can be used as required.¼ Benign tumors that are asymptomatic should be observed. Excision can be considered for those that are found to be growing over time.¼ Biopsies of tumors of the brachial plexus are associated with the risk of nerve injury. Despite this, they should be performed for tumors that are suspected to be malignant before starting definitive treatment.¼ For malignant tumors, treatment decisions should be discussed at multidisciplinary tumor boards, and include both the oncology and peripheral nerve surgical team, musculoskeletal radiology, neuroradiology, and general radiology.

Outcomes of complete neurotomy and immediate repair of the musculocutaneous nerve for treatment of elbow spasticity.

Neurotomy interrupts the stretch reflex and can be used for the treatment of spasticity. We hypothesized that neurotomy with nerve repair reduces spasticity while preserving motor function due to the preferential recovery of efferent over afferent fibres. This study reports the 1-year outcomes of neurotomy and immediate repair of the musculocutaneous nerve in the proximal arm for treatment of elbow flexor spasticity, comparing these to outcomes in the literature for neurectomy without nerve repair. A total of 10 adult patients with spasticity of the elbow flexors from stroke or traumatic brain injury who had undergone neurotomy and immediate repair of the musculocutaneous nerve were prospectively studied. The results suggest that this procedure effectively reduces elbow flexor spasticity, improves elbow resting position, active elbow extension and is useful for achieving patient goals with effects lasting at least 12 months.Level of evidence: IV (therapeutic).

Scapular Elevation Sign - A New Sign in Evaluation of Thoracic Outlet Syndrome.

Background: We noted that patients with thoracic outlet syndrome (TOS) have elevation of the ipsilateral scapula and named this the scapular elevation sign (SES). The aim was to determine the prevalence of SES in a normal cohort, compare SES with other provocative tests and to determine the treatment effect on SES. Methods: First, normal asymptomatic subjects were prospectively assessed to determine the prevalence of SES in a normal cohort. Second, patients with TOS were retrospectively examined for the presence of SES and four provocative tests: supraclavicular pressure, scalene test, elevated arm stress test (EAST) and the military brace manoeuvre. All patients were initially treated non-surgically. Surgery was offered to patients with persistent symptoms at 6 months. Patients were re-examined for the presence of the SES after treatment. Results: The prevalence of SES in our normal cohort was 4% (2/53). Our study cohort included 20 patients with TOS. The SES was positive in 18 patients (90%). Supraclavicular pressure was positive in 11 (55%), scalene test in 13 (65%), EAST in 9 (45%) and military brace manoeuvre in 11 patients (55%). Following non-surgical treatment, six patients had symptom resolution, three had improvement, nine persistent symptoms and two were lost to follow-up. The SES was positive in one out of six patients with symptom resolution, two out of three patients with improvement and in all nine patients with persistent symptoms. Patients with persistent symptoms underwent surgery with symptom resolution in eight and improvement in one patient. The SES remained positive in two patients after surgical treatment. Conclusions: The SES is simple and sensitive, does not rely on variations in performance of the test and suitable for diagnosis and assessment of outcomes of TOS. Level of Evidence: Level III (Diagnostic).

Updates in peripheral nerve surgery of the upper extremity: diagnosis and treatment options.

The loss of function resulting from peripheral nerve injuries confers a significant burden to the patient and society. The treatment of peripheral nerve injuries requires an accurate diagnosis and formulation of a functional reconstructive plan. Advances in peripheral nerve imaging complement electrodiagnostic studies, and provide us with detailed information regarding the status of nerve injury, repair, and regeneration in order to prognosticate recovery and determine the need for surgical intervention. When direct nerve repair is not possible, the methods for bridging a nerve gap are the nerve autograft, allograft and conduit. While current research supports the use of conduits and nerve allografts for shorter nerve gaps, the nerve autograft still remains the gold standard for bridging a nerve gap. When direct nerve repair or nerve grafting fails, or is anticipated to be insufficient, nerve transfers are an alternative for reconstruction. Knowledge of axonal counts, upper limb innervation patterns, location and clustering of upper limb peripheral nerves allows for the design of new nerve transfers. The options of nerve transfers for radial, ulnar and median nerve injuries are outlined, as well as their outcomes. Nerve transfers are an attractive option for restoring motor and sensory function while minimizing donor site morbidity. However, one must consider their limitations, and preserve donor sites for secondary tendon transfer options. This article presents the latest information regarding the imaging of peripheral nerves, methods to bridge a nerve gap, and nerve transfers to aid the peripheral nerve surgeon in choosing a reconstructive plan.

Norwegian Open Fracture Management System: Outcomes After 10 Years Working in Low-Resource Settings in Cambodian Hospitals.

INTRODUCTION: The treatment of open lower limb fractures represents a major challenge for any trauma surgeon, and this even more so in resource-limited areas. The aim of the study is to describe the intervention, report the treatment plan, and observe the effectiveness of the Norwegian Open Fracture Management System in saving lower limbs in rural settings. MATERIALS AND METHODS: A retrospective and prospective interventional study was carried out in the period 2011 through 2017 in six rural hospitals in Cambodia. The fractures were managed with locally produced external fixators and orthosis developed in 2007. Based on skills and living locations, two local surgeons and one paramedic without reconstructive surgery experience were selected to reach the top of the reconstructive ladder and perform limb salvage surgeries. This study evaluated 56 fractures using the Ganga Hospital Open Injury Score (GHOIS) for Gustilo-Anderson Type IIIA and Type IIIB open fracture classification groups. RESULTS: The primary success rate in open tibia fractures was 64.3% (95% CI, 50.3 - 76.3). The average treatment time to complete healing for all of the patients was 39.6 weeks (95% CI, 34.8 - 44.4). A percentage of 23.2% (95% CI, 13.4 - 36.7) experienced a deep infection. Fifteen of the patients had to undergo soft tissue reconstruction and 22 flaps were performed. Due to non-union, a total of 15 bone grafts were performed. All of the 56 patients in the study gained limb salvage and went back to work. CONCLUSION: The given fracture management program proves that low-resource countries are able to produce essential surgical tools at high quality and low price. Treatment with external fixation and functional bracing, combined with high-level training of local surgeons, demonstrates that a skilled surgical team can perform advanced limb salvage surgery in low-resource settings.

SARS-CoV-2 in migrant worker dormitories: Geospatial epidemiology supporting outbreak management.

BACKGROUND: Migrant worker dormitories-residential complexes where 10-24 workers share living spaces-account for the majority of cases of SARS-CoV-2 infection in Singapore. To prevent overspill of transmission to the wider population, starting in early April 2020, residents were confined to their dormitories while measures were put in place to arrest the spread of infection. This descriptive study presents epidemiological data for a population of more than 60 000 migrant workers living in two barracks-style and four apartment-style dormitories located in western Singapore from April 3 to June 10, 2020. METHODS: Our report draws from data obtained over the first 50 days of outbreak management in order to describe SARS-CoV-2 transmission in high-density housing environments. Cumulative counts of SARS-CoV-2 cases and numbers of housing units affected were analyzed to report the harmonic means of harmonic means of doubling times and their 95% confidence intervals (CI). RESULTS: Multiple transmission peaks were identified involving at least 5467 cases of SARS-CoV-2 infection across six dormitories. Our geospatial heat maps gave an early indication of outbreak severity in affected buildings. We found that the number of cases of SARS-CoV-2 infection doubled every 1.56 days (95% CI 1.29-1.96) in barracks-style buildings. The corresponding doubling time for apartment-style buildings was 2.65 days (95% CI 2.01-3.87). CONCLUSIONS: Geospatial epidemiology was useful in shaping outbreak management strategies in dormitories. Our results indicate that building design plays an integral role in transmission and should be considered in the prevention of future outbreaks.

Emergency Hand and Reconstructive Microsurgery in the COVID-19-Positive Patient.

The case spectrum in hand surgery is one of extremes-purely elective day surgery cases under local anesthesia to mangling limb injuries that require immediate, and frequently, lengthy, surgery. Despite the cancellation of most elective orthopedic and plastic surgical procedures, hand surgeons around the world continue to see a steady stream of limb-threatening cases such as severe trauma and infections that require emergent surgical care. With the increase in community-spread, an increasing number of COVID-19-infected patients may be asymptomatic or have mild, nonspecific or atypical symptoms. Some of them may already have an ongoing, severe infection. The time-sensitive nature of some of these cases means that hand surgeons may need to operate urgently on patients who may be suspected of COVID-19 infections, often before confirmatory test results are available. General guidelines for perioperative care of the COVID-19-positive patient have been published. However, our practices differ from those of general orthopedic and plastic surgery, primarily because of the focus on trauma. This article discusses the perioperative and technical considerations that are essential to manage the COVID-19 patient requiring emergency care, without compromising clinical outcomes and while ensuring the safety of the attending staff.

Functional Restoration Following Resection of Malignant Peripheral Nerve Sheath Tumour of the Median Nerve: A Case Report.

Management of malignant peripheral nerve sheath tumours (MPNSTs) is primarily surgical, involving surgical resection with wide margins, and frequently radiation therapy. When a MPNST involves a major peripheral nerve, wide resection leads to significant distal neurologic deficits. A patient who underwent resection of a MPNST involving the median nerve above the elbow is presented. Staged tendon and nerve transfers were performed to restore sensation to the thumb and index finger, thumb opposition and flexion, finger flexion and forearm pronation. These included: 1. radial sensory nerve branches to digital nerves of thumb and index finger, 2. ulnar nerve branch of flexor carpi ulnaris to pronator teres, 3. brachioradialis to flexor pollicis longus, 4. side-to-side transfer of flexor digitorum profundus tendon of index finger to middle, ring and little fingers, 5. extensor indicis proprius to abductor pollicis brevis. The rationale, approach, and favourable results of functional reconstruction in this patient are detailed.

Upper Extremity Axon Counts and Clinical Implications for Motor Nerve Transfer.

BACKGROUND: Nerve transfers are planned based on the following parameters: location, number of branches, and axon count matching of the donor and recipient nerves. The authors have previously defined the former two in upper limb muscles. In the literature, axon counts are obtained from various sources, using different methods of histomorphometry. This study describes the axon counts of the same primary motor nerve branches from the authors' previous study using a uniform method of manual histomorphometry and completes the authors' blueprint of upper limb neuromuscular anatomy for reconstructive surgery. METHODS: The distal ends of the primary nerve branches of 23 upper limb muscles were harvested from 10 fresh frozen cadaveric upper limbs. Manual quantitative histomorphometry was performed by two independent investigators, and the average was reported. RESULTS: The primary nerve branches of the arm muscles had higher average axon counts (range, 882 to 1835) compared with those of the forearm muscles (range, 267 to 883). In the forearm, wrist flexor (range, 659 to 746) and extensor (range, 543 to 745) nerve branches had axons counts that were similar to those of potential donors (e.g., supinator, n = 602; pronator teres, n = 625; flexor digitorum superficialis, n = 883; and flexor digitorum profundus, n = 832). CONCLUSIONS: Apart from describing the axon counts of the upper limb, the authors have found that the forearm axon counts are very comparable. This insight, when combined with information on the location and number of primary nerve branches, will empower surgeons to tailor bespoke nerve transfers for every clinical situation.

Nerve Compression in the Upper Limb.

Nerve compression occurs in fibro-osseous tunnels as the nerves cross joints. The pathology involves traction and adhesion, aside from compression. This can occur at multiple sites along the course of the nerve. Regardless of level, clinical assessment is standard and a systematic approach to uncover all sites of compression is advised. Evolution of management for carpal tunnel and cubital tunnel syndrome is reviewed with an emphasis on natural history and nonsurgical treatment, which are not commonly discussed. Treatment is multimodal and the systemic factors that contribute to nerve dysfunction should also be addressed.

Structural Adaptations of the Primate Flexor Carpi Ulnaris After Tendon Transfer.

PURPOSE: Muscle remodeling occurs after tendon transfer. However, it is not known whether these adaptations are permanent and clinically significant. This study examined the early and late structural adaptations following a standard tendon transfer in a primate model. METHODS: A flexor carpi ulnaris (FCU) to extensor digitorum communis (EDC) transfer was performed in 8 adult monkeys. A sham operation was performed in the contralateral forearm. Four animals were sacrificed at 5 months (early cohort) and 4 at 16 months (late cohort). The transferred FCU, contralateral FCU, and EDC muscles were removed for analysis. Fiber length (FL), physiological cross-sectional area (PCSA), and gross morphology of the transferred FCU were compared with the contralateral EDC and FCU. RESULTS: In the early cohort, the FL of the transferred FCU was longer than the control FCU and similar to the contralateral EDC. The PCSA of the transferred FCU was lower than that of the control FCU but greater than the control EDC. In the late cohort, the difference in FL and PCSA between the transferred FCU and the control FCU persisted. The PCSA of the transferred FCU was similar to that of the control EDC. The bipennate transferred FCU had also undergone gross morphological changes to resemble the multipennate EDC. CONCLUSIONS: This study demonstrates, in a primate model, that the FCU undergoes structural adaptations to resemble the EDC following an FCU-to-EDC transfer. However, these adaptations are incomplete and not sustained over time. CLINICAL RELEVANCE: This study demonstrates that there is muscle plasticity in tendon transfers in a primate model. However, it is important to match potential donor muscles to the recipient during tendon transfer.

Time needed to resolve patient complaints and factors influencing it: a cohort study.

OBJECTIVE: There has been an increase in the number and complexity of patient complaints against healthcare institutions. An understanding of the resources needed in this area is important for proper planning. DESIGN: Cohort study. SETTING: A 1250-bed tertiary-care teaching hospital. PARTICIPANTS: All patient complaints received between 1 February 2014 and 31 January 2015 were prospectively included in this cohort study. MAIN OUTCOME MEASURES: The amount of time spent on the investigation and liaising with the complainant for each case was recorded. The complainant's personal details and characteristics were recorded anonymously. RESULTS: In total, 908 patient complaints were recorded from 801 individuals during the study period. Longer median person-hours were spent on managing complaints that were brought forward by men (1.48 h), those who were distant relatives of the patients (2.08 h), foreigners (1.58 h) and non-subsidised patients (1.83 h). Patient complaints falling into the categories of clinical domain (3.00 h) and patient rights (2.54 h), quality (3.00 h) and safety (2.83 h) required the longest median time to manage. Multiple logistic regression analysis revealed that the total amount of time spent on the complaints was predicted by the gender of the complainant, the relationship of the complainant with the patient, the subsidy status of the patient, the severity and the domain of the complaint. CONCLUSIONS: This study reported the time required to manage patient complaints in a larger tertiary-care academic medical centre. Predictors of the time spent on resolving patient complaints can be used as parameters for resource planning.

Upper Extremity Innervation Patterns and Clinical Implications for Nerve and Tendon Transfer.

BACKGROUND: The authors previously studied the intramuscular innervation of 150 upper limb muscles and demonstrated that certain patterns of intramuscular innervation allowed muscles to be split into compartments with independent function. This study aims to determine the location, extramuscular course, and number of motor nerve branches of upper limb peripheral nerves. The authors want to combine this information with their previous work to create a blueprint of upper limb neuromuscular anatomy that would be useful in reconstructive surgery. METHODS: Ten fresh frozen cadaveric upper limbs were dissected. The origin of branches from the peripheral nerve trunk, their course, and the number of motor nerves per muscle were determined. The authors reviewed all the images of the Sihler-stained muscles from their earlier study. RESULTS: Motor nerve branches arise at the intersection of nerve trunk and muscle belly and are clustered near the origin of muscle groups. Two patterns of extramuscular innervation were noted, with one group having a single motor nerve and another group with consistently more than one motor nerve. A modified classification of muscles was proposed based on the orientation of muscle fibers to the long axis of the limb, the number of muscle compartments, and the number of heads of origin or the tendons of insertion. CONCLUSIONS: Motor nerve clusters can be located based on fixed anatomical landmarks. Muscles with multiple motor nerves have morphology that allows them to be split into individual compartments. The authors created a muscle and nerve blueprint that helps in planning nerve and split muscle transfers.

Impact of inpatient Care in Emergency Department on outcomes: a quasi-experimental cohort study.

BACKGROUND: Hospitals around the world are faced with the issue of boarders in emergency department (ED), patients marked for admission but with no available inpatient bed. Boarder status is known to be associated with delayed inpatient care and suboptimal outcomes. A new care delivery system was developed in our institution where boarders received full inpatient care from a designated medical team, acute medical team (AMT), while still residing at ED. The current study examines the impact of this AMT intervention on patient outcomes. METHODS: We conducted a retrospective quasi-experimental cohort study to analyze outcomes between the AMT intervention and conventional care in a 1250-bed acute care tertiary academic hospital in Singapore. Study participants included patients who received care from the AMT, a matched cohort of patients admitted directly to inpatient wards (non-AMT) and a sample of patients prior to the intervention (pre-AMT group). Primary outcomes were length of hospital stay (LOS), early discharges (within 24 h) and bed placement. Secondary outcomes included unplanned readmissions within 3 months, and patient's bill size. χ2- and Mann-Whitney U tests were used to test for differences between the cohorts on dichotomous and continuous variables respectively. RESULTS: The sample comprised of 2279 patients (1092 in AMT, 1027 in non-AMT, and 160 in pre-AMT groups). Higher rates of early discharge (without significant differences in the readmission rates) and shorter LOS were noted for the AMT patients. They were also more likely to be admitted into a ward allocated to their discipline and had lower bill size compared to non AMT patients. CONCLUSIONS: The AMT intervention improved patient outcomes and resource utilization. This model was noted to be sustainable and provides a potential solution for hospitals' ED boarders who face a gap in inpatient care during their crucial first few hours of admissions while waiting for an inpatient bed.

Bone Marrow Derived Mesenchymal Stem Cell Augmentation of Rabbit Flexor Tendon Healing.

BACKGROUND: This study investigated the effect of mesenchymal stem cell implantation on flexor tendon healing using a rabbit model of flexor tendon repair. Specifically, we compared the difference between autologous and allogeneic stem cells. The influence of cell number on the outcome of flexor tendon healing was also investigated. METHODS: Repaired tendons on the rear paws of rabbits were randomly assigned into four groups: control group, 1 million autologous cells, 1 million allogeneic cells, and 4 million allogeneic cells. Rabbits were sacrificed at 3 or 8 weeks after surgery. RESULTS: Implantation of 4 million stem cells resulted in a significant increase in range of motion compared with control group at three weeks after surgery. The positive staining of collagen I in healing tendons was enhanced in stem cell treated groups three weeks after surgery. However, stem cells did not improve biomechanical properties of flexor tendons. CONCLUSIONS: High dose stem cells attenuated adhesions in the early time point following flexor tendon repair. Further work is needed determine the value of stem cell therapy in flexor tendon healing in humans.

The value of the tender muscle sign in detecting motor recovery after peripheral nerve reconstruction.

PURPOSE: Squeezing a denervated muscle a few weeks after nerve repair produces a characteristic response in patients. This response is observed before any clinical evidence of motor recovery. We called this response the tender muscle sign (TMS) and wanted to determine whether this sign was related to the recovery of motor power. METHODS: We studied 31 adults with unilateral brachial plexus injuries who underwent 50 procedures for reinnervation of the supraspinatus, deltoid, and biceps. Follow-up was monthly for the first year and at 3-monthly intervals thereafter. Average duration of follow-up was 3.3 years. The TMS was sought at each visit. The presence of the TMS, when it was first observed, and time to Medical Research Council (MRC) grade 1 and 3 recoveries were recorded. The sensitivity, specificity, and predictive values of TMS for motor recovery were calculated. RESULTS: The TMS was always detected earlier than palpable muscle contraction. It was significantly associated with recovery of MRC grade 1 and 3 motor power. The sensitivity of TMS for MRC grade 1 recovery was 96% and specificity was 100%. For MRC grade 3 recovery, it had 97% sensitivity and 27% specificity. The positive predictive value was 100% for MRC grade 1 recovery and 83% for MRC grade 3. The negative predictive value was 50% for MRC grade 1 recovery and 75% for MRC grade 3. CONCLUSIONS: Previous studies have demonstrated the presence of nocioceptive receptors in human skeletal muscle. The reinnervation of these receptors by the regenerating axons results in cramp-like tenderness when the muscle is squeezed. This response is specific to a reinnervated muscle and cannot be elicited in denervated or normally innervated muscle. The TMS is a simple, clear, and early indicator of muscle reinnervation that is useful in monitoring motor recovery after nerve regeneration. TYPE OF STUDY/LEVEL OF EVIDENCE: Diagnostic IV.

Biomechanical comparison of different suturing techniques in rabbit medial gastrocnemius muscle laceration repair.

INTRODUCTION: Skeletal muscle laceration is a common injury. Repair of disrupted delicate tissue is still a clinical challenge for surgeons. A few different muscle repair techniques have been reported. However, the best muscle repair technique has not been identified. The aim of the present study is to compare the biomechanical features of different repair techniques in muscles to identify the most effective one. MATERIAL AND METHODS: New Zealand white rabbits (2.5-3 kg) were euthanized and medial gastrocnemius muscles were isolated. The muscles were completely transected with scalpels and then repaired by 3 different techniques, namely, (1) 2-strand mattress, (2) 4-strand Kessler (with epitendinous suture), and (3) Mason-Allen. To measure suture performance, the repaired specimens were mounted onto a mechanical testing machine Instron 5543. The muscles were loaded to failure at a constant speed of 60 mm/min. Data collected from Merlin v5.31 software were used to compute the biomechanical properties of each specimen. RESULTS: There was no significant difference in the mean maximum load of Kessler group (15.5 N) and Mason-Allen group (13.2 N), whereas the mean maximum load of the control (Mattress) group (4.4 N) was significantly smaller than the other 2 groups. Moreover, Kessler stitches were the stiffest among the 3. It is noteworthy that the mechanisms of failure were different: Kessler stitches were all pulled out longitudinally, whereas Mason-Allen stitches transmitted load across the laceration and ruptures occur at areas adjacent to the stitches, indicating that muscle is the weakest element in the biomechanical testing. CONCLUSIONS: Both Kessler and Mason-Allen stitches have shown better biomechanical features compared with the control group. Further study has to be done to compare the effect of these 2 techniques on muscle regeneration and scar formation in an in vivo model.

The dorsal metatarsal artery perforator flap.

Few options exist for the resurfacing of web-space and small soft tissue defects of the dorsum of the distal foot. The study examines the anatomy of the second to fourth dorsal metatarsal arteries in 16 fresh frozen cadavers to determine if the anatomy correlates to that in the hand, permitting the design of local flaps based on perforators of these vessels. A clinical case is also presented, illustrating the efficacy of such a perforator-based flap.Sixteen Asian cadaveric lower limbs were used for this study. The specimens were prepared with latex dye injection. Dissection under loupe magnification was carried out to determine the position and caliber of the cutaneous perforators from the dorsal metatarsal arteries, and the spread of the latex dye in the skin from these cutaneous perforators. One clinical case illustration of this perforator-based flap for distal foot defect resurfacing is presented.In our cadaveric study, each second to fourth dorsal metatarsal artery had between 2 and 5 cutaneous perforators with calibers of 0.5 to 0.7 mm in diameter. The most distal cutaneous perforator was present consistently, always arising between the heads of the respective metatarsals.In conclusion, the vascular anatomy of the second to fourth dorsal metatarsal arteries is similar to that in the hand, thus allowing for the design of reliable perforator-based flaps for distal foot resurfacing.