Diagnosis of Ulnar Neuropathy at the Elbow Using Ultrasound - A Comparison to Electrophysiologic Studies.

PURPOSE: Given the relatively high false negative rate of electrodiagnostic studies (EDX) in patients with clinically diagnosed ulnar neuropathy at the elbow (UNE), we sought to determine whether an alternative objective test could more effectively detect UNE. Additionally, we proposed to determine the relationship between the cross-sectional area (CSA) of the ulnar nerve on ultrasound (US), EDX, and clinical symptoms. METHODS: This was a retrospective study of patients presenting with symptomatic UNE. The performance characteristics of EDX versus ultrasound were calculated using the clinical diagnosis of UNE as the reference standard. Standard EDX studies and US of the ulnar nerve were analyzed. Maximal CSA of the ulnar nerve and EDX severity were analyzed for patients with each combination of US-positive/negative and EDX-positive/negative findings. RESULTS: Analysis was performed on 89 patients and 115 nerves with signs and symptoms of cubital tunnel syndrome. In total, 56 (49%) nerves were diagnosed as mild UNE, 32 (28%) nerves were diagnosed as moderate UNE, 17 (15%) nerves were diagnosed as severe UNE, and 10 (8%) nerves were negative for UNE by EDX. Maximal-maximal CSA was highly correlated with disease severity as determined by nerve conduction studies/electromyography. Compared with EDX+/US+, patients with EDX-/US+ showed higher rates of ulnar sensory loss and elbow tenderness with similar rates of positive Tinel and intrinsic muscle atrophy. In this sample of patients with clinically diagnosed UNE, 91.3% of the patients demonstrated positive EDX studies, whereas 94.8% had a positive US. CONCLUSIONS: Ultrasound is an alternative to EDX that could be incorporated clinically in the diagnosis and management of UNE. Ultrasound was able to consistently detect clinically positive cubital tunnel syndrome demonstrating its utility as a confirmatory or supplemental test to the clinical assessment if one is required. Ultrasound additionally may be able to better identify patients with early stages of UNE with negative EDX findings. TYPE OF STUDY/LEVEL OF EVIDENCE: Diagnostic IV.

Where Does Ultrasound Fit in the Diagnostic Algorithm for Cubital Tunnel Syndrome?

BACKGROUND: Ultrasound (US) has emerged as a promising supplement to electrodiagnostic studies (EDX) in the diagnosis of cubital tunnel syndrome (CuTS) and has potential to be performed by novice operators. Our objective is to understand the discrepancies in assessment between the two modalities and to assess the utility of US in CuTS diagnosis by a novice operator. METHODS: Patients who presented to a single tertiary academic medical center and clinically diagnosed with CuTS were prospectively enrolled. Electrodiagnostic studies were performed along with US measurements of the cross-sectional area (CSA) of the ulnar nerve by both a board-certified physiatrist and novice operator. Electrodiagnostic study and US outcomes were compared among four diagnostic impression groups: EDX-/US-, EDX+/US-, EDX-/US+, and EDX+/US+. RESULTS: Sixteen patients were classified as abnormal by both EDX and US, 14 were classified abnormal by US only, 3 were classified abnormal by EDX only, and 6 were classified normal by both EDX and US (P = .008, K = 0.14). The EDX+/US+ group had a significantly reduced sensory amplitude compared with the EDX-/US+ (P = .04) group. Diagnostic classifications between a board-certified physiatrist and novice operator were in moderate agreement (K = 0.58, P = .08). CONCLUSIONS: Ultrasound detected a greater proportion of patients as abnormal than EDX. A subset of patients with clinical diagnoses of CuTS had normal sensory amplitudes but increased maximum nerve CSAs. Competency in US may be easily acquired with minimal training, suggesting its potential to be extended for use by other members of the health care team.

Ultrasound Assessment of the Ulnar Nerve Around the Elbow and Diagnosis of Cubital Tunnel Syndrome, Clinical Outcomes.

BACKGROUND: There is increased interest in ultrasound (US) for the diagnosis of cubital tunnel syndrome (CuTS). We hypothesize that ulnar nerve cross-sectional area (CSA) correlates with disease severity and electrodiagnostic studies (EDX). METHODS: ARetrospective review was performed at a tertiary medical center. One hundred seventeen patients (166 ulnar nerves) were evaluated. Maximum CSA at 3 points around the elbow (proximal, groove, and distal) and EDX results (American Board of Electrodiagnostic Medicine-certified physiatrist's interpretations) were collected. RESULTS: US was positive (CSA > 0.1 cm2) in 95/117 cases (81.20%) versus 84/117 (71.79%) positive for EDX. CuTS patients treated surgically had significantly greater (0.13 cm2, standard deviation [SD] 0.038) preoperative CSA than non-operative patients (0.10 cm2, SD 0.033) (p = .003). CSA increased as EDX increased in severity; mild (0.116 cm2, SD 0.031), moderate (0.121 cm2, SD 0.035), and severe (0.163 cm2, SD 0.047) with a significant difference between the mild and severe groups (P = .001) and between the moderate and severe groups (p = .01). Significant differences were seen between patients with positive US and EDX studies compared to those with negative US and EDX in the average physical function scores (57.26, SD 8.57 versus 43.18, SD 7.70; p < .001); average sleep scores (50.14, SD 9.53 versus 56.62, SD 7.31; p = .02); average physical function scores (43.04, SD 8.68 versus 57.08, SD 6.34; p < .001) and average depression scores (49.10, SD 10.88 versus 45.043, SD 7.06; p = .02). CONCLUSIONS: US is a reliable tool for diagnosis and surgical decision-making for CuTS. TYPE OF STUDY/LEVEL OF EVIDENCE: Diagnostic/III.

Association of Patient-Reported Outcomes Measurement Information System Measures With Injection and Surgical Treatment Response in Patients With De Quervain Tenosynovitis.

PURPOSE: Treatment of de Quervain tenosynovitis is largely empiric. Patient-Reported Outcomes Management Information System (PROMIS) scores at the time of diagnosis might provide insights into the probability of success of nonsurgical management and predict the necessity for surgical treatment. We aimed to identify which, if any, of the PROMIS metrics may be used to identify patients who will opt for surgery or be managed with injection alone. METHODS: Patients presenting to a tertiary academic medical center from 2014 to 2019, with a sole diagnosis of de Quervain tenosynovitis, were identified and separated by initial and most invasive treatment of either injection or surgery. These groups were then dichotomized using cut points of more than one SD from the mean on the PROMIS physical function and pain interference scales, and a logistic regression model was used to determine the odds ratio of surgical intervention. RESULTS: Patients who had low physical function or high pain interference had significantly increased odds of ultimately undergoing surgery. Age ranging from 40 to 60 years and female sex were also associated with increased odds of undergoing surgery. CONCLUSIONS: Patients who scored lower than 40 for physical function or higher than 60 for pain interference had significantly increased odds of eventually undergoing surgical release for de Quervain tenosynovitis. PROMIS scores may identify patients who are likely to fail steroid injections as a sole nonsurgical intervention and inform an individualized discussion about surgical management of this condition. TYPE OF STUDY/LEVEL OF EVIDENCE: Prognostic IV.

Epitenon-derived cells comprise a distinct progenitor population that contributes to both tendon fibrosis and regeneration following acute injury.

Flexor tendon injuries are common and heal poorly owing to both the deposition of function- limiting peritendinous scar tissue and insufficient healing of the tendon itself. Therapeutic options are limited due to a lack of understanding of the cell populations that contribute to these processes. Here, we identified a bi-fated progenitor cell population that originates from the epitenon and goes on to contribute to both peritendinous fibrosis and regenerative tendon healing following acute tendon injury. Using a combination of genetic lineage tracing and single cell RNA-sequencing (scRNA-seq), we profiled the behavior and contributions of each cell fate to the healing process in a spatio-temporal manner. Branched pseudotime trajectory analysis identified distinct transcription factors responsible for regulation of each fate. Finally, integrated scRNA-seq analysis of mouse healing with human peritendinous scar tissue revealed remarkable transcriptional similarity between mouse epitenon- derived cells and fibroblasts present in human peritendinous scar tissue, which was further validated by immunofluorescent staining for conserved markers. Combined, these results clearly identify the epitenon as the cellular origin of an important progenitor cell population that could be leveraged to improve tendon healing.

Initial PROMIS Scores Correlate With Operative and Nonoperative Management of Lateral Epicondylitis.

BACKGROUND: Lateral epicondylitis (LE) is a common source of elbow pain. Treatment options include physical therapy (PT), corticosteroid injection, or surgery, but the efficacy of each remains unclear. In this study, we compare Patient-Reported Outcomes Measurement Information System (PROMIS) scores between patients treated both operatively and nonoperatively for LE. METHODS: Patients presenting to a tertiary academic medical center from February 2015 to December 2018 with a diagnosis of LE were identified. Those with initial and follow-up PROMIS physical function (PF), pain interference (PI), and Depression scores were included and stratified according to treatment. Single-factor analysis of variance testing was used to compare PROMIS scores between intervention types. RESULTS: In all, 982 patients were initially identified with the diagnosis of LE and documented PROMIS scores. Initial treatment consisted of 266 patients receiving formal PT, 238 patients receiving injections, 20 patients undergoing surgery, and 296 patients receiving no formal treatment. At final follow-up, 235 (44.8%) patients had been treated with isolated PT, 237 (45.1%) with injections, and 52 (9.9%) with surgery. Patients who underwent formal PT had the highest initial PF scores when compared with all other interventions. Patients who underwent operative management had higher initial PI scores than those who pursued nonoperative management. CONCLUSIONS: Patient-Reported Outcomes Measurement Information System PF and PI may be useful for determining which treatment course patients suffering from LE are likely to pursue. Pain as a limiting factor in daily living may be a better indication for operative management as opposed to physical metrics.

Development of a Murine Model of Pyogenic Flexor Tenosynovitis.

BACKGROUND: Pyogenic flexor tenosynovitis is a debilitating infection of the hand flexor tendon sheath with high morbidity despite standard treatments of empiric antibiotics with irrigation and debridement. In vivo studies in the available literature have used avian models, but these models are difficult to scale and maintain. The purpose of this study was to demonstrate the plausibility of a murine model of pyogenic flexor tenosynovitis utilizing bioluminescence imaging and tissue analysis at harvest. METHODS: A 2-µL inoculate of bioluminescent Xen29 Staphylococcus aureus or sterile phosphate-buffered saline solution (sPBS) was administered to the tendon sheath of 36 male C57BL/6J mice. The infectious course was monitored by bioluminescence imaging (BLI) via an in vivo imaging system, gross anatomic deformity, and weight change. The infected hind paws were harvested at 4 time points: 24 hours, 72 hours, 1 week, and 2 weeks for histological analysis using Alcian blue, hematoxylin, and Orange-G staining. Two-way analysis of variance with the Sidak multiple comparison test was used to assess differences in bioluminescence and weight at each time point. RESULTS: The infected cohort displayed significantly elevated bioluminescence values, had reductions in weight, and exhibited swelling of the infected digit throughout the course of infection. By day 4, most infected mice saw a substantial decrease in BLI signal intensity; however, 2 infected mice exhibited persistent BLI intensity through day 14. Histological analysis of the infected cohort showed tissue disorganization and the presence of a cellular infiltrate in and around the flexor tendon sheath. CONCLUSIONS: A murine model of pyogenic flexor tenosynovitis is possible and can serve as an experimental platform for further investigation of the pathophysiology of pyogenic flexor tenosynovitis. CLINICAL RELEVANCE: This animal model can be utilized in elucidating the basic molecular and/or cellular mechanisms of pyogenic flexor tenosynovitis while simultaneously evaluating novel therapeutic strategies.

Clinical utilization of species-specific immunoassays for identification of Staphylococcus aureus and Streptococcus agalactiae in orthopedic infections.

Staphylococcus aureus and Streptococcus agalactiae (Group B streptococcus, GBS) are common causes of deep musculoskeletal infections (MSKI) and result in significant patient morbidity and cost to the healthcare system. One of the major challenges with MSKI is the lack of faithful diagnostics to correctly identify the primary pathogen, as standard culture-based assays are prone to false positives in the case of polymicrobial infections, and false negatives due to limitations in sample acquisition and antibiotic use before presentation. To improve upon our current diagnostic methods for MSKI, we developed a multiplex immunoassay for antigen-specific IgGs in serum (Luminex), and medium enriched for newly synthesized antibodies (MENSA) for anti-S. aureus and GBS generated from cultured peripheral blood mononuclear cells (PBMCs) of orthopedic infection patients undergoing surgical treatment. Samples were obtained from 110 MSKI patients: 80 diabetic foot ulcer, 21 periprosthetic joint infection, 5 septic arthritis, 2 spine, 1 hand, and 1 fracture-related infection (FRI). Anti-S. aureus and anti-GBS antibody titers were compared to culture results to assess their concordance in identifying the pathogens. Immunoassay, particularly MENSA, showed high diagnostic potential for monomicrobial S. aureus and GBS orthopedic infections (AUC > 0.95). MENSA also demonstrated diagnostic potential for GBS polymicrobial orthopedic infection and for GBS DFU (AUC > 0.83 for both). Serum showed high diagnostic potential for S. aureus PJI (AUC > 0.95). Taken together, these findings support the development of species-specific immunoassays for the identification of causal pathogens in active MSKI, especially in conjunction with standard culture.

NF-κB activation persists into the remodeling phase of tendon healing and promotes myofibroblast survival.

Although inflammation is necessary during the early phases of tissue repair, persistent inflammation contributes to fibrosis. Acute tendon injuries often heal through a fibrotic mechanism, which impedes regeneration and functional recovery. Because inflammation mediated by nuclear factor κB (NF-κB) signaling is implicated in this process, we examined the spatial, temporal, and cell type-specific activation profile of canonical NF-κB signaling during tendon healing. NF-κB signaling was maintained through all phases of tendon healing in mice, including the remodeling phase, and tenocytes and myofibroblasts from the Scleraxis (Scx) lineage were the predominant populations that retained NF-κB activation into the late stages of repair. We confirmed persistent NF-κB activation in myofibroblasts in human tendon scar tissue. Deleting the canonical NF-κB kinase, IKKß, in Scx-lineage cells in mice increased apoptosis and the deposition of the matrix protein periostin during the late stages of tendon repair, suggesting that persistent NF-κB signaling may facilitate myofibroblast survival and fibrotic progression. Consistent with this, myofibroblasts in human tendon scar samples displayed enhanced prosurvival signaling compared to control tissue. Together, these data suggest that NF-κB may contribute to fibrotic tendon healing through both inflammation-dependent and inflammation-independent functions, such as NF-κB-mediated cell survival.

A Comparison of PROMIS Physical Function and Pain Interference Scores in Patients With Carpal Tunnel Syndrome: Research Collection Versus Routine Clinical Collection.

Background: There is a concern that patients may answer patient-reported outcome (PRO) questionnaires differently depending on the purpose-clinical care or research (eg, "Hawthorne effect"). We sought to determine whether Patient-Reported Outcomes Management Information System (PROMIS) scores differ at the same clinic visit based on whether a patient was completing the PRO tool for study or clinical care purposes. Methods: Patients presenting to one surgeon at an academic medical center hand clinic were asked to complete PROMIS Physical Function (PF) and Pain Interference (PI) questionnaires as part of routine care. Those diagnosed with carpal tunnel syndrome from February 2015 to April 2017 were then asked to participate in a clinical research project, which had them complete PROMIS PF and PROMIS PI again. Data from those who completed both routine and research PROs at each visit were compared. Between the 2 settings, test-retest reliability was determined using Pearson correlation coefficients (r), and internal consistency was evaluated using Cronbach α. Results: A total of 128 unique office visits representing 67 patients fit our inclusion criteria. There was a strong correlation between PROMIS PF and PI in the research and patient care setting (PF: r = 0.82, P < .01; PI: r = 0.83, P < .01). Both domains had a Cronbach α of 0.90. The PROMIS PF scores were not different between the 2 groups (P = .19), but the PROMIS PI scores were slightly different (P < .01). Conclusions: Patients appear to be consistent when completing PROMIS for both clinical care and research, supporting the idea that data obtained in either setting are generalizable and appropriate for research purposes.

Reduction Loss After Distal Radius Fracture Fixation With Locked Volar Plates.

Distal radius fractures are among the most common injuries in the upper extremity. While many studies have looked at the maintenance of reduction with volar locking plates, there is a paucity of literature comparing the ability of different plates to maintain reduction over time. This study reviews the ability of various plates to maintain radiographic reduction at union after distal radius fracture treatment. Loss of some aspect of fracture reduction was routinely observed following locked volar plating regardless of implant. However, choice of implant did have a significant impact on final radiographic alignment, particularly with respect to volar tilt and ulnar variance. Yet, selecting between a fixed angle versus a variable angle was not found to make a difference in maintaining reduction. The authors recommend that surgeons take these findings into consideration when selecting a volar locking plate. (Journal of Surgical Orthopaedic Advances.

Neurolysis with Amniotic Membrane Nerve Wrapping for Treatment of Secondary Wartenberg Syndrome: A Preliminary Report.

BACKGROUND: Entrapment of the superficial sensory branch of the radial nerve (SRN) commonly results in debilitating pain of the dorsoradial wrist. Symptom relief following SRN neurolysis is often incomplete or temporary due to recurrent perineural scarring. METHODS: We performed a retrospective review with prospective follow-up of all patients with SRN neuropathy who were treated with neurolysis and nerve wrapping using an amnion-based allograft adhesion barrier over a one-year interval. Measured outcomes included pain rated by Visual Analog Scale (VAS) and Quick Disabilities of the Arm, Shoulder and Hand (QuickDASH) functional outcome scores. RESULTS: Three females satisfied inclusion. At mean follow-up of 28.9 months, all three patients exhibited improved pain (mean VAS change -4.7 ± 0.6), function (mean QuickDASH change -40 ± 5), and subjective satisfaction. No adverse events or reactions to the implanted tissue occurred. CONCLUSIONS: SRN entrapment neuropathy was safely and effectively treated with neurolysis and amnion nerve wrapping in this small series. Use of this technique for perineural scar prevention warrants additional study in larger groups of patients and in other upper extremity entrapment neuropathies.

Timing of Debridement and Infection Rates in Open Fractures of the Hand: A Systematic Review.

Background: Literature on open fracture infections has focused primarily on long bones, with limited guidelines available for open hand fractures. In this study, we systematically review the available hand surgery literature to determine infection rates and the effect of debridement timing and antibiotic administration. Methods: Searches of the MEDLINE, EMBASE, and Cochrane computerized literature databases and manual bibliography searches were performed. Descriptive/quantitative data were extracted, and a meta-analysis of different patient cohorts and treatment modalities was performed to compare infection rates. Results: The initial search yielded 61 references. Twelve articles (4 prospective, 8 retrospective) on open hand fractures were included (1669 open fractures). There were 77 total infections (4.6%): 61 (4.4%) of 1391 patients received preoperative antibiotics and 16 (9.4%) of 171 patients did not receive antibiotics. In 7 studies (1106 open fractures), superficial infections (requiring oral antibiotics only) accounted for 86%, whereas deep infections (requiring operative debridement) accounted for 14%. Debridement within 6 hours of injury (2 studies, 188 fractures) resulted in a 4.2% infection rate, whereas debridement within 12 hours of injury (1 study, 193 fractures) resulted in a 3.6% infection rate. Two studies found no correlation of infection and timing to debridement. Conclusions: Overall, the infection rate after open hand fracture remains relatively low. Correlation does exist between the administration of antibiotics and infection, but the majority of infections can be treated with antibiotics alone. Timing of debridement, has not been shown to alter infection rates.

Rethinking Pyogenic Flexor Tenosynovitis: Biofilm Formation Treated in a Cadaveric Model.

Introduction Pyogenic flexor tenosynovitis (PFT) of the hand remains a challenging problem that often requires surgical irrigation and parenteral or oral antibiotics. The authors hypothesize that the pathophysiology and microenvironment of PFT can be likened to that of periprosthetic joint infections (PJIs), in which bacteria thrive in a closed synovial space with limited blood supply. As such, they postulate that PFT is also facilitated by bacterial attachment and biofilm formation rendering standard treatments less effective. In this study, they evaluate infected tendons for the presence of biofilm and explore new treatment strategies. Methods Fresh human cadaveric hand tendons were harvested and divided into 0.5-cm segments. Samples were sterilized and inoculated with 1 × 10 4 CFU/mL green fluorescent Staphylococcus aureus (GFP-SA) for 48 hours at 37°C. After saline washing to remove plank tonic bacteria, samples were treated for 24 hours with (1) saline irrigation, (2) antibiotics (vancomycin), (3) corticosteroids, or (4) antibiotics/corticosteroid combined. Samples were visualized using confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). Results Following bacterial challenge, CLSM revealed heterogeneous green fluorescence representing bacterial attachment with dense biofilm formation. SEM at > 3,000X, also demonstrated bacterial colonization in grape-like clusters consisted with a thick matrix characteristic of biofilm. Bacterial load by direct colony counting decreased by 18.5% with saline irrigation alone, 42.6% with steroids, 54.4% with antibiotics, and 77.3% with antibiotics/steroids combined ( p < 0.05). Conclusion Staphylococcus aureus readily formed thick biofilm on human cadaveric tendons. The addition of both local antibiotics and corticosteroids resulted in greater decreases in biofilm formation on flexor tendons than the traditional treatment of saline irrigation alone. We suggest rethinking the current treatment of PFT and recommend considering a strategy more analogous to PJI management with the adjunctive use of local antibiotics, corticosteroids, and mechanical agitation.

Wide Awake Trigger Finger Release Surgery: Prospective Comparison of Lidocaine, Marcaine, and Exparel.

BACKGROUND: Local anesthetics are routinely used in hand surgery for procedures such as trigger finger releases (TFRs). However, little is known as to the difference in efficacy and patient experience with various local anesthetics. We prospectively evaluated the efficacy of Lidocaine (L), Marcaine (M), and Exparel (E) to elucidate differences in pain scores and opioid consumption between these groups. METHODS: All consecutive TFR performed over a 6-month period in 2014 at our institution were divided to receive Lidocaine, Marcaine, or Marcaine with postoperative Exparel. Pain levels, daily opioid consumption, and adverse reactions were recorded and analyzed for postoperative day (POD) 0-3. RESULTS: A total of 154 patients were enrolled (L:53, M:50, E:51). The Lidocaine group reported the highest pain levels for POD 0-1. Marcaine pain levels were similar to Exparel on POD 0 but higher on POD 1. Opioid consumption on POD 0-1 was significantly different with E:27%, M:58% and L:59% as was the number of pills consumed (E:0.70, M: 1.08 and L:1.62). In addition, 50% of Exparel patients required no pain medications and experienced significantly less adverse reactions (E:4%, M:10%, L:13%). By POD 2-3, there were no statistical differences between the 3 groups. CONCLUSIONS: Patients treated with Marcaine attain better pain control than Lidocaine on POD 0-1but only patients who received Exparel maintained the lowest pain levels through POD 0-3 while using little-to-no opioid medications and with less adverse reactions than Lidocaine or Marcaine alone.

Optimal Positioning for Volar Plate Fixation of a Distal Radius Fracture: Determining the Distal Dorsal Cortical Distance.

Distal radius fractures are currently among the most common fractures of the musculoskeletal system. With a population that is living longer, being more active, and the increasing incidence of osteoporosis, these injuries will continue to become increasingly prevalent. When operative fixation is indicated, the volar locking plate has recently become the treatment of choice. However, despite its success, suboptimal position of the volar locking plate can still result in radiographic loss of reduction. The distal dorsal cortical distance is being introduced as an intraoperative radiographic tool to help optimize plate position and minimize late loss of fracture reduction.