Pain Interference Prior to and 1 Year After Surgery for Adult Traumatic Brachial Plexus Injury.

PURPOSE: Pain after brachial plexus injury (BPI) can be severely debilitating and is poorly understood. We hypothesized that pain interference (PI) ("the extent to which pain hinders engagement in life") would be predicted by depression, anxiety, severity of pain symptoms, and poorer preoperative muscle function. METHODS: Among patients in a prospective multicenter BPI cohort study, 37 completed Patient-Reported Outcomes Measurement Information System (PROMIS) PI questionnaires before and 1 year after surgery. At both times, participants completed anxiety and depression questionnaires and BPI-specific measures of pain symptoms, physical limitations, and emotional recovery. Surgeon-graded muscle testing, injury severity, age at the time of injury, body mass index, and time from injury to surgery were included. We performed a bivariate analysis of predictors for preoperative and 1-year PROMIS PI followed by multivariable regression modeling using stepwise selection and Bayesian Information Criterion to select covariates. RESULTS: Before surgery, the mean PROMIS PI score was 60.8 ± 11.0, with moderate correlations between PROMIS PI and depression, as well as between PROMIS PI and functional limitations. At 1 year after surgery, the mean PROMIS PI score was 59.7 ± 9.5. There was no difference in preoperative and 1-year PROMIS PI. There were strong correlations between PROMIS PI and pain symptoms, functional limitations, and emotional aspects of recovery at the 1-year follow-up that remained significant in multivariable regression. There were no notable associations between muscle testing and PI. CONCLUSIONS: Pain interference remained substantial and elevated in BPI patients 1 year after surgery. We noted strong associations between PI and pain symptoms, functional limitations, and emotional aspects of recovery. These findings demonstrate the persistence of pain as a feature throughout life after BPI and that its treatment should be considered a priority alongside efforts to improve extremity function. TYPE OF STUDY/LEVEL OF EVIDENCE: Prognosis IV.

Referral Patterns Associated With Delayed Care for Traumatic Brachial Plexus Injuries.

PURPOSE: Traumatic brachial plexus injuries (BPI) are devastating, time-sensitive conditions that often require definitive treatment at academic tertiary care centers. Delays to presentation and surgery have been associated with inferior outcomes. In this study, we evaluate referral patterns associated with delayed presentation and late surgery in traumatic BPI patients. METHODS: Patients diagnosed with a traumatic BPI at our institution from 2000 to 2020 were identified. Medical charts were reviewed for demographic characteristics, prereferral work-up, and referring provider characteristics. Delayed presentation was defined as greater than 3 months from date of injury to initial evaluation by our brachial plexus specialists. Late surgery was defined as greater than 6 months from date of injury. Multivariable logistic regression was used to identify factors associated with delayed presentation or surgery. RESULTS: A total of 99 patients were included, 71 of whom underwent surgery. Sixty-two patients presented delayed (62.6%), with 26 receiving late surgery (36.6%). There were similar rates of delayed presentation or late surgery by referring provider specialty. Patients whose initial diagnostic EMG was ordered by the referring provider prior to initial presentation at our institution were more likely to have a delayed presentation (76.2% vs 31.3%) and undergo late surgery (44.9% vs 10.0%). CONCLUSIONS: Delayed presentation and late surgery in traumatic BPI patients were associated with initial diagnostic EMG ordered by the referring provider. CLINICAL RELEVANCE: Delayed presentation and surgery have been associated with inferior outcomes in traumatic BPI patients. We recommend that providers direct patients with clinical concern of traumatic BPI directly to a brachial plexus center without further work-up before referral and encourage referral centers to accept these patients.

The Influence of Psychosocial Factors on Disability and Expected Improvement Before Surgery for Adult Traumatic Brachial Plexus Injury.

PURPOSE: Psychosocial factors influence pain and recovery after extremity trauma and may be targets for early intervention. This may be of particular interest for patients with adult traumatic brachial plexus injury (BPI), given the broad and devastating impact of the injury. We hypothesized that there would be an association between depressive symptoms, anxiety, and pain interference with preoperative disability and expectations for improvement after BPI surgery. METHODS: We enrolled 34 patients into a prospective multicenter cohort study for those undergoing surgery for adult traumatic BPI. Before surgery, participants completed Patient-Reported Outcome Measurement Information System scales for pain interference, anxiety, and depressive symptoms, and a validated BPI-specific measure of disability and expected improvement. We performed Pearson correlation analysis between pain interference, anxiety symptoms, and depressive symptoms with (A) disability and (B) expected improvement. We created separate linear regression models for (A) disability and (B) expected improvement including adjustment for severity of plexus injury, age, sex, and race. RESULTS: Among 34 patients, there was a moderate, statistically significant, correlation between preoperative depressive symptoms and higher disability. This remained significant in a linear regression model adjusted for severity of plexus injury, age, sex, and race. There was no association between severity of plexus injury and disability. Depressive symptoms also were moderately, but significantly, correlated with higher expected improvement. This remained significant in a linear regression model adjusted for severity of plexus injury, age, sex, and race. CONCLUSIONS: Depressive symptoms are associated with greater disability and higher expected improvement before BPI surgery. Screening for depressive symptoms can help BPI teams identify patients who would benefit from early referral to mental health specialists and tailor appropriate expectations counseling for functional recovery. We did not find an association between severity of BPI and patient-reported disability, suggesting either that the scale may lack validity or that the sample is biased. LEVEL OF EVIDENCE: Prognostic II.

Role of high-resolution peripheral nerve magnetic resonance imaging in diagnosing median nerve tethering in a case of both-bone forearm fracture in a child.

Forearm fractures are common injuries in pediatric patients. We present a case of median nerve tethering as a complication of both-bone forearm fracture in a child, with an emphasis on MRI as an appropriate and important complement to clinical and electrodiagnostic examination. Early intervention is essential because delayed surgical management of median nerve tethering can result in poor clinical outcomes as a result of irreversible muscle denervation. In this case, we highlight the importance of MRI to facilitate management, including early surgical intervention when appropriate, in median neuropathy following forearm fractures.

Long-term radiographic outcomes and functional evaluation of ulnar shortening osteotomy in patients with ulnar impaction syndrome and reverse oblique sigmoid notch: a retrospective case series study.

BACKGROUND: Ulnar shortening osteotomy (USO) is an effective treatment for ulnar impaction syndrome. However, there have been reports of osteoarthritis (OA) at the distal radioulnar joint (DRUJ) when USO was performed on patients with a reverse oblique sigmoid notch. This study aimed to evaluate the radiographic and functional outcomes following USO in patients with a reverse oblique sigmoid notch. METHODS: We retrospectively reviewed patients having a reverse oblique sigmoid notch who underwent USO for ulnar impaction syndrome between 2002 and 2013. We evaluated radiographic changes of the DRUJ and functional outcomes of patients. RESULTS: We enrolled 22 patients (22 wrists) with an average age of 49.6 years and a mean follow-up of 93.2 (range, 36-179; standard deviation [SD], 38.2) months. We found that there were changes in the inclination angle of the sigmoid notch, from an average reverse oblique of 14.9o (range, 11o-23o; SD, 3.4o) preoperatively to a more parallel 5.1o (range, 0o-11o; SD, 3.2o) at the final follow-up. The functional results at the final follow-up were good, with a mean visual analogue scale for pain of 0.2 (range, 0-1; SD, 0.4) at rest and 1.3 (range, 0-3; SD, 0.9) during activity, QuickDASH of 15.1 (range, 2.3-34.1; SD, 8.8), and modified Mayo Wrist Score of 91.6 (range, 70-100; SD, 6.4). Seven wrists (31.8%) had changes compatible with OA, but the wrists did not exhibit a significantly worse function when compared to wrists without OA changes, except for supination motion and grip strength. CONCLUSIONS: For patients with a reverse oblique sigmoid inclination following USO, we observed that the inclination angle had a tendency to become parallel and some patients developed OA at the DRUJ. However, long-term functional outcomes could still be good. The reverse oblique sigmoid inclination does not seem to be an absolute contraindication for USO.

A Cadaveric Study on the Utility of the Levator Scapulae Motor Nerve as a Donor for Brachial Plexus Reconstruction.

PURPOSE: The purpose of the study was to evaluate the utility of the levator scapulae motor nerve (LSN) as a donor nerve for brachial plexus nerve transfer. We hypothesized that the LSN could be transferred to the suprascapular nerve (SSN) or long thoracic nerve (LTN) with a reliable tension-free coaptation and appropriate donor-to-recipient axon count ratio. METHODS: Twelve brachial plexus dissections were performed on 6 adult cadavers, bilaterally. We identified the LSN, spinal accessory nerve (SAN), SSN, and LTN. Each nerve was prepared for transfer and nerve redundancies were calculated. Cross-sections of each nerve were examined histologically, and axons counted. We transferred the LSN to target first the SSN and then the LTN, in a tension-free coaptation. For reference, we transferred the distal SAN to target the SSN and LTN and compared transfer parameters. RESULTS: Three cadavers demonstrated 2 LSN branches supplying the levator scapulae. The axon count ratio of donor-to-recipient nerve was 1:4.0 (LSN:SSN) and 1:2.1 (LSN:LTN) for a single LSN branch and 1:3.0 (LSN:SSN) and 1:1.6 (LSN:LTN) when 2 LSN branches were available. Comparatively, the axon count ratio of donor-to-recipient nerve was 1:2.5 and 1:1.3 for the SAN to the SSN and the LTN, respectively. The mean redundancy from the LSN to the SSN and the LTN was 1.7 cm (SD, 3.1 cm) and 2.9 cm (SD, 2.8 cm), and the redundancy from the SAN to the SSN and the LTN was 4.5 (SD, 0.7 cm) and 0.75 cm (SD, 1.0 cm). CONCLUSIONS: These data support the use of the LSN as a potential donor for direct nerve transfer to the SSN and LTN, given its adequate redundancy and size match. CLINICAL RELEVANCE: The LSN should be considered as an alternative nerve donor source for brachial plexus reconstruction, especially in 5-level injuries with scarce donor nerves. If used in lieu of the SAN during primary nerve reconstruction, trapezius tendon transfer for improved external rotation would be enabled.

Surgical Treatment of Iatrogenic Nerve Injury Following Arthroscopic Capsulolabral Repair.

PURPOSE: Case reports of nerve injuries following arthroscopic capsulolabral repair emphasize the proximity of major nerves to the glenoid. This study describes preoperative localization using nerve-sensitive magnetic resonance imaging in a small cohort of patients with iatrogenic nerve injuries following arthroscopic capsulolabral repair and the outcomes of nerve repair in these patients. METHODS: Cases of iatrogenic nerve injury following arthroscopic capsulolabral repair referred to 2 surgeons from January 2017 to December 2019 were identified. Clinical charts, electrodiagnostic testing, magnetic resonance imaging studies, and operative reports were reviewed. RESULTS: Four cases of iatrogenic nerve injury were identified. The time to presentation to our institution ranged from 2 weeks to 8 years. The axillary nerves in 3 cases were tethered by a suture at the inferior glenoid, whereas 1 case had a suture tied around the radial and median nerves inferior to the glenohumeral joint capsule. One case underwent excision and nerve transfer, 1 underwent excision and nerve repair, and 2 underwent suture removal and neurolysis. Open and arthroscopic approaches, including a recently described approach to the axillary nerve in the "blind zone," were used. Three cases demonstrated good recovery of all affected motor and sensory functions after surgery. At the 10-month follow-up, 1 case had persistent weakness, but there was evidence of axonal regeneration on electrodiagnostic testing. CONCLUSIONS: Arthroscopic capsulolabral repair places regional nerves, particularly the axillary nerve, at risk owing to their proximity to the joint capsule and inferior glenoid. Patients with neuropathic pain in the distribution of affected nerves with corresponding sensorimotor loss following arthroscopic capsulolabral surgery should undergo focused magnetic resonance imaging with nerve-sensitive sequences and electrodiagnostic testing to localize the injury. The use of multiple surgical windows to the axillary nerve in the "blind zone" enables full visualization for neurolysis, suture removal, and nerve repair or transfer. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic V.

Outcomes of Microneurolysis of Hourglass Constrictions in Chronic Neuralgic Amyotrophy.

PURPOSE: Wide variability in the recovery of patients affected by neuralgic amyotrophy (NA) is recognized, with up to 30% experiencing residual motor deficits. Using magnetic resonance imaging and ultrasound (US), we identified hourglass constrictions (HGCs) in all affected nerves of patients with chronic motor paralysis from NA. We hypothesized that chronic NA patients undergoing microsurgical epineurolysis and perineurolysis of constrictions would experience greater recovery compared with patients managed nonsurgically. METHODS: We treated 24 patients with chronic motor palsy from NA and HGCs identified on magnetic resonance imaging and US either with microsurgical epineurolysis and perineurolysis of HGCs (11 of 24) or nonsurgically (13 of 24). Muscle strength (both groups) and electrodiagnostic testing (EDX) (operative group) was performed before and after surgery. Preoperative EDX confirmed muscle denervation in the distribution of affected nerve(s). All patients met criteria for microneurolysis: 12 months without improvement since onset or failure of clinical and EDX improvement after 6 months documented by 3 successive examinations, each at least 6 weeks apart. RESULTS: Mean time from onset to surgery was 12.5 ± 4.0 months. Average time to most recent post-onset follow-up occurred at 27.3 months (range, 18-42 months; 15 nerves). Average time to latest follow-up among nonsurgical patients was 33.6 months (range, 18-108 months; 16 nerves). Constrictions involved individual fascicular groups (FCs) of the median nerve and the suprascapular, axillary and radial nerves proper (HGCs). Nine of 11 operative patients experienced clinical recovery compared with 3 of 13 nonsurgical patients. EMG revealed significant motor unit recovery from axonal regeneration in the operative group. CONCLUSIONS: Microsurgical epineurolysis and perineurolysis of FCs and HGCs was associated with significantly improved clinical and nerve regeneration at an average follow-up of 14.8 months compared with nonsurgical management. We recommend microneurolysis of HGCs and FCs as a treatment option for patients with chronic NA who have failed to improve with nonsurgical treatment. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Fascicular constrictions above elbow typify anterior interosseous nerve syndrome.

INTRODUCTION: In this study we tested the hypothesis that fascicular constrictions (FCs) of the median nerve proximal to the elbow joint characterize anterior interosseous nerve syndrome (AINS). METHODS: Magnetic resonance neurography (MRN) and ultrasound (US) examinations were evaluated in 45 patients with clinically suspected AINS. All 22 patients at site 1 underwent MRN and 8 underwent US; all 23 patients at site 2 underwent US. RESULTS: Median nerve FCs were identified in all MRN cases; FCs and/or fascicular enlargements were identified in 88% of US cases. Most FCs were in the mediannerve posterior/posteromedial region and were proximal to the elbow joint line (mean distance: MRN, 5.4 cm; US, 7.5 cm), with the exception of a single FC (located 1 cm distal). No extrinsic compression of median or anterior interosseous nerves was identified in the arm or forearm. DISCUSSION: AINS is a noncompressive neuropathy characterized by median nerve FCs in the arm.

Overcoming the Axillary Nerve Blind Spot Through the Deltopectoral and Axillary Approaches: A Cadaveric Study.

PURPOSE: The aim of this study was to evaluate the feasibility of exploring the axillary nerve (AN) at the 6 o'clock position (blind spot) using the deltopectoral approach, with the interval lateral to the conjoint tendon (CJT) or combined with the axillary approach. METHODS: Four ANs were dissected combining the deltopectoral approach-medial to the CJ (A), the deltopectoral approach-lateral to the CJT (B) and the axillary approach (C) in 3 sequences: A-B-C, B-A-C, and C-B-A. After the first approach was completed, the proximal and distal margins were marked. Additional exposure with the second and third approaches and the 6 o'clock position were also marked. Then, the AN was excised and the amount of exposed nerve with the 3 approaches was measured. RESULTS: The deltopectoral approach-medial to the conjoint tendon did not allow exposure of the AN at the 6 o'clock position. Six o'clock position exposure was accomplished using the lateral interval of the deltopectoral and the axillary approaches. A deltopectoral approach lateral to the CJT allowed exploration of the AN at the blind spot, but not the terminal branches. The axillary approach was able to expose the AN at the 6 o'clock position, the terminal branches, but not the nerve-muscle junction. Combining the 3 approaches exposed 81% to 94% of the total length of the AN. CONCLUSIONS: The deltopectoral approach allowed visualization of the AN at the 6 o'clock position when explored lateral to the CJT. The axillary approach allowed visualization of the terminal branches of the AN and the 6 o'clock position of the glenoid. CLINICAL RELEVANCE: The deltopectoral approach lateral to the conjoint tendon allows the surgeon to assess continuity of the AN at the 6-o'clock position and to perform a neurolysis. If nerve repair, nerve grafting, or nerve transfer is attempted, a combination of the 3 approaches could be used.

Cadaveric Evaluation of Myelinated Nerve Fiber Count in the Nerve to the Gracilis Muscle in Relation to Use as a Free Functional Muscle Transfer for Elbow Flexion.

BACKGROUND: Optimizing axon count is essential for successful nerve transfer surgery, and a donor-to-recipient axon count ratio greater than 0.7:1 has been associated with improved outcomes. A gracilis free functioning muscle transfer (FFMT) is an option to restore elbow flexion, but its axon count has not been evaluated. Our aim was to quantify the axon count of the nerve to the gracilis muscle. METHODS: The nerve to the gracilis was dissected in 10 fresh frozen adult cadaveric hindquarter specimens (four females and six males). The length of the nerve to the gracilis was measured and a biopsy taken. A validated histologic preparation technique was utilized, and axons were counted. The mean length and axon counts were calculated. RESULTS: The average axon count in the nerve to the gracilis was 818 (range = 684-1,000, standard deviation [SD] = 116). The average length was 98 mm (range = 81-115 mm, SD = 13 mm). CONCLUSION: Our study found the average axon count in the nerve to the gracilis was 818. Prior literature suggests axon count ratio greater than 0.7:1 is associated with better clinical outcomes. Using data from prior studies, the spinal accessory, three intercostal, and two intercostal nerves are all sufficient for the transfer to the nerve to the gracilis with donor to recipient ratios of 1.7:1, 1.3:1, and 0.9:1, respectively.

Biomechanical Properties of Nitinol Staples: Effects of Troughing, Effective Leg Length, and 2-Staple Constructs.

PURPOSE: Nitinol memory compression staples are a recent addition to carpal bone fixation. Compared with traditional staples, they have been shown to have superior compression at the far cortex relative to standard and traditional compression staples. The purpose of this study was to (1) determine the effective leg length of different nitinol staples, (2) confirm the effect of 1 versus 2 staples on biomechanical compression, and (3) determine the effect of troughing (countersinking the staple into bone) the bone on staple biomechanical properties. METHODS: Three commonly used nitinol staples of various bridge and leg lengths were used in a bicortical sawbones block construct. There were 3 separate constructs tested, which included single staple, double staple, and troughed. We measured compression force, stiffness, and bending strength for each construct before and after cyclical 4-point bending. Compression mapping was used to determine the effective leg length of each staple, which included the distance that compression extended beyond the tips of the staple legs. RESULTS: Effective leg length for each staple construct extended 2 mm distal to the tip of the shortest staple leg. Two staple constructs more than doubled compressive force and increased bending strength by greater than 90% in all staple types. There was no loss of compressive force before or after loading for single, double, or troughed constructs with any staple type. CONCLUSIONS: This study supports that nitinol staples do not have to be placed bicortically to achieve adequate compression; placing staples 2 mm short of the far cortex has the same compression as bicortical placement; and troughing of the bone will not significantly diminish the biomechanical properties of the construct. CLINICAL RELEVANCE: Better understanding of the effective leg length of nitinol staples provides support that bicortical placement is not necessary for adequate compression. This study supports troughing bone to minimize implant prominence.

A Comparison Between Two Collagen Nerve Conduits and Nerve Autograft: A Rat Model of Motor Nerve Regeneration.

PURPOSE: To compare recovery in a rat model of sciatic nerve injury using a novel polyglycolic acid (PGA) conduit, which contains collagen fibers within the tube, as compared with both a hollow collagen conduit and nerve autograft. We hypothesize that a conduit with a scaffold will provide improved nerve regeneration over hollow conduits and demonstrate no significant differences when compared with autograft. METHODS: A total of 72 Sprague-Dawley rats were randomized into 3 experimental groups, in which a unilateral 10-mm sciatic defect was repaired using either nerve autograft, a hollow collagen conduit, or a PGA collagen-filled conduit. Outcomes were measured at 12 and 16 weeks after surgery, and included bilateral tibialis anterior muscle weight, voltage and force maximal contractility, assessment of ankle contracture, and nerve histology. RESULTS: In all groups, outcomes improved between 12 and 16 weeks. On average, the autograft group outperformed both conduit groups, and the hollow conduit demonstrated improved outcomes when compared with the PGA collagen-filled conduit. Differences in contractile force, however, were significant only at 12 weeks (autograft > hollow collagen conduit > PGA collagen-filled conduit). At 16 weeks, contractile force demonstrated no significant difference but corroborated the same absolute results (autograft > hollow collagen conduit > PGA collagen-filled conduit). CONCLUSIONS: Nerve repair using autograft provided superior motor nerve recovery over the 2 conduits for a 10-mm nerve gap in a murine acute transection injury model. The hollow collagen conduit demonstrated superior results when compared with the PGA collagen-filled conduit. CLINICAL RELEVANCE: The use of a hollow collagen conduit provides superior motor nerve recovery as compared with a PGA collagen-filled conduit.

Brachial plexitis or neuritis? MRI features of lesion distribution in Parsonage-Turner syndrome.

INTRODUCTION: This study seeks to characterize lesion distribution in Parsonage-Turner Syndrome (PTS) using high-resolution MRI. METHODS: MRIs of 27 patients with clinically confirmed PTS were reviewed. Two radiologists independently evaluated the brachial plexus proper, side and terminal plexus branches, and more distal, upper extremity nerves. RESULTS: All patients had at least 1 clinically involved nerve. MRI revealed that the plexus appeared normal in 24 of 27 patients; in 3 other patients, signal hyperintensity was seen immediately proximal to the take-off of abnormal side or terminal branch nerves. Focal intrinsic constrictions were detected in 32 of 38 nerves. MRI interobserver agreement was high (Cohen's κ = 0.839). DISCUSSION: MRI findings, corroborated by electrodiagnostic testing, localized abnormalities to plexus branches and peripheral nerves, suggesting that PTS is characterized by 1 or more mononeuropathies rather than changes involving a portion of or the complete plexus proper. These results may improve diagnosis, prognostication, and management. Muscle Nerve 58: 359-366, 2018.

The Psychological Impact of Adult Traumatic Brachial Plexus Injury.

PURPOSE: There is a high incidence of posttraumatic stress disorder (PTSD), depression, suicide risk, and psychological distress after orthopedic trauma and hand and upper-extremity injury. Although patients with traumatic adult brachial plexus injury are particularly vulnerable to psychologic distress, minimal clinical data exist about this cohort of patients. In this study, we sought to discover the prevalence of depression, PTSD, suicidal ideation, and substance abuse. METHODS: Between February, 2013 and July, 2014, during scheduled preoperative and/or postoperative appointments, the social worker at a metropolitan brachial plexus center conducted psychosocial assessments and questionnaire assessments of 21 patients evaluating for PTSD, depression, and substance use using 3 validated scales: PTSD Checklist-Specific, Patient Health Questionnaire-8, and National Institute on Drug Abuse Quick Screen. RESULTS: Brachial plexus injury strongly affected self-reported psychological well-being; 7 of 21 (33.3%) divulged suicidal ideation. Diagnosticand Statistical Manual of Mental Disorders, Fifth Edition (DSM-V) diagnosis was supported by PTSD Checklist-Specific and Patient Health Questionnaire-8 results: 4 of 21 (19.0%) met criteria for PTSD and 4 of 21 (19.0%) exhibited clinical depression. Patients reported no changes in social alcohol and tobacco use or substance abuse. CONCLUSIONS: Brachial plexus injury significantly influences psychological well-being and daily functioning. As a result, patients experience a high prevalence of PTSD, depression, and suicidal ideation. Patients with brachial plexus injury have a high prevalence of psychological concerns and challenges that require continued attention throughout treatment. TYPE OF STUDY/LEVEL OF EVIDENCE: Prognostic IV.

The electrodiagnostic natural history of parsonage-turner syndrome.

INTRODUCTION: Recovery from Parsonage-Turner syndrome (PTS) is generally favorable, although recovery times have been shown to vary, in part because there are no universally accepted outcome measures. In this study, we describe the electrodiagnostic natural history of this condition based on objective electrodiagnostic testing, and propose that complete electrodiagnostic recovery can be seen as early as 1 year. METHODS: Twenty-six subjects with 29 affected nerves confirmed as PTS were followed every 3 months for electrodiagnostic testing, or until full reinnervation was confirmed. RESULTS: Twenty-three cases (79.3%) demonstrated electrodiagnostic evidence of initial recovery at a mean of 5.8 months. Nine cases (31%) showed complete electrodiagnostic recovery at a mean of 1 year. When excluding cases with <1 year of follow-up, 52.9% achieved complete electrodiagnostic recovery. CONCLUSIONS: In contrast to previous reports, full electrodiagnostic recovery of PTS was demonstrated at a mean of 1 year in > 50% of patients with longer term follow-up. Muscle Nerve 56: 737-743, 2017.

MRI bullseye sign: An indicator of peripheral nerve constriction in parsonage-turner syndrome.

INTRODUCTION: The role of MRI in identifying hourglass constrictions (HGCs) of nerves in Parsonage-Turner syndrome (PTS) is largely unknown. METHODS: Six patients with PTS and absent or minimal recovery underwent MRI. Surgical exploration was performed at identified pathologic sites. RESULTS: The time between symptom onset and surgery was 12.4 ± 6.9 months; the time between MRI and surgery was 1.3 ± 0.6 months. Involved nerves included suprascapular, axillary, radial, and median nerve anterior interosseous and pronator teres fascicles. Twenty-three constriction sites in 10 nerves were identified on MRI. A "bullseye sign" of the nerve, identified immediately proximal to 21 of 23 sites, manifested as peripheral signal hyperintensity and central hypointensity orthogonal to the long axis of the nerve. All constrictions were confirmed operatively. CONCLUSIONS: In PTS, a bullseye sign on MRI can accurately localize HGCs, a previously unreported finding. Causes of HGCs and the bullseye sign are unknown. Muscle Nerve 56: 99-106, 2017.

What Demographic and Clinical Characteristics Correlate With Expectations With Trapeziometacarpal Arthritis?

BACKGROUND: Pretreatment variables have been shown to be associated with the fulfillment of patient expectations, yet in treating thumb trapeziometacarpal osteoarthritis (OA) it remains unclear how patient expectations correlate with the effectiveness of treatment. An increased understanding of the variables that affect patient expectations enables tailored patient education and patient-provider communication. QUESTIONS/PURPOSES: (1) Is there a correlation between patient demographics and clinical characteristics, and the expectations the patients have when seeking treatment for trapeziometacarpal OA? (2) What factors are independently associated with the total expectations score and frequency of expecting "back to normal" among patients treated for trapeziometacarpal OA? METHODS: Between March 2011 and October 2013, 89 patients of all 96 eligible patients seeking treatment for trapeziometacarpal OA were approached and agreed to participate in this study. Participants completed a validated expectations survey measuring the number of expectations and the degree of improvement expected. Comparative analysis of demographic and clinical characteristics and multivariate regression analysis against patients' expectations were performed to assess and identify factors that correlate with the number and degree of expectations. Sample size was determined with an a priori power analysis (with 80% power and statistical significance set at p < 0.05), which showed that 88 patients were needed to detect the minimal clinical difference of 12 points in the Michigan Hand Questionnaire; we then increased this by 10% to allow for potential dropouts. RESULTS: After controlling for potential confounding variables such as age, hand dominance, and work status, the following factors were associated with a higher expectations score: choice of surgery (ß = 11.5; 95% CI, 0.7-23.8; p = 0.044), female gender (ß = 19.0; 95% CI, 5.3-32.7; p = 0.007), and dominant side affected (ß = -41.6; 95% CI, -63.7 to -19.5; p < 0.001). For the frequency of "back to normal" responses, surgical treatment (ß = 7.4; 95% CI, 2.3-12.4; p = 0.005) and history of previous injury (ß = 8.2; 95% CI, 0.1-16.3; p = 0.047) were independently associated factors after controlling for confounding variables. There were no independent associations with age, marital status, work status, depression or anxiety, or prior contralateral surgery. CONCLUSIONS: Patients whose dominant side was affected, were female, and chose surgical treatment, had higher total expectations. Patients who reported an antecedent injury and chose surgical treatment more frequently expected a return to normal. With identification of these factors, orthopaedic surgeons can recognize patients who are prone to higher expectations, and, thus, have the opportunity to implement efficient pretreatment education. In addition, identification of specific factors enables a focused measure of the effect of these factors on the fulfillment of expectations. LEVEL OF EVIDENCE: Level II, prognostic study.

Patients With Thumb Carpometacarpal Arthritis Have Quantifiable Characteristic Expectations That Can Be Measured With a Survey.

BACKGROUND: Although patient expectations associated with major orthopaedic conditions have shown clinically relevant and variable effects on outcomes, expectations associated with thumb carpometacarpal (CMC) arthritis have not been identified, described, or analyzed before, to our knowledge. QUESTIONS/PURPOSES: We asked: (1) Do patients with thumb CMC arthritis express characteristic expectations that are quantifiable and have measurable frequency? (2) Can a survey on expectations developed from patient-derived data quantitate expectations in patients with thumb CMC arthritis? METHODS: The study was a prospective cohort study. The first phase was a 12-month-period involving interviews of 42 patients with thumb CMC arthritis to define their expectations of treatment. The interview process used techniques and principles of qualitative methodology including open-ended interview questions, unrestricted time, and study size determined by data saturation. Verbatim responses provided content for the draft survey. The second phase was a 12-month period assessing the survey for test-retest reliability with the recruitment of 36 participants who completed the survey twice. The survey was finalized from clinically relevant content, frequency of endorsement, weighted kappa values for concordance of responses, and intraclass coefficient and Cronbach's alpha for interrater reliability and internal consistency. RESULTS: Thirty-two patients volunteered 256 characteristic expectations, which consisted of 21 discrete categories. Expectations with similar concepts were combined by eliminating redundancy while maintaining original terminology. These were reduced to 19 items that comprised a one-page survey. This survey showed high concordance, interrater reliability, and internal consistency, with weighted kappa values between 0.58 and 0.78 (95% CI, 0.39-0.78; p < 0.001); intraclass correlation coefficient of 0.94 (95% CI, 0.94-0.98; p < 0.001), and Cronbach's alpha values of 0.94 and 0.95 (95% CI, 0.91-0.96; p < 0.001). The thumb CMC arthritis expectations survey score is convertible to an overall score between 0 to 100 points calculated on the basis of the number of expectations and the degree of improvement expected, with higher scores indicating higher expectations. CONCLUSIONS: Patients with thumb CMC arthritis volunteer a characteristic and quantifiable set of expectations. Using responses recorded verbatim from patient interviews, a clinically relevant, valid, and reliable expectations survey was developed that measures the physical and psychosocial expectations of patients seeking treatment for CMC arthritis. The survey provides a calculable score that can record patients' expectations. Clinical application of this survey includes identification of factors that influence fulfilment of these expectations. LEVEL OF EVIDENCE: Level II, prospective study.

Axon Counts Yield Multiple Options for Triceps Fascicular Nerve to Axillary Nerve Transfer.

PURPOSE: To evaluate the relative axonal match between potential donor and recipient nerves, so that maximal reinnervation potential may be reached with the least chance of donor site morbidity. METHODS: In 10 fresh-frozen cadaveric specimens, the main trunk and anterior, posterior, sensory and teres minor branches of the axillary nerve were identified, as were the radial nerve branches to the long, medial, and lateral heads of the triceps. The swing distances of the triceps fascicular nerve branches and the axillary nerve branches relative to the inferior border of the teres major muscle were recorded. Histomorphological analysis and axon counts were performed on sections of each branch. RESULTS: The median number of axons in the main axillary trunk was 7,887, with 4,052, 1,242, and 1,161 axons in the anterior, posterior, and teres minor branches, respectively. All specimens had a single long head triceps branch (median, 2,302 axons), a range of 1 to 3 branches to the medial head of the triceps (composite axon count, 2,198 axons), and 1 to 3 branches to the lateral head of the triceps (composite average, 1,462 axons). The medial and lateral head branches had sufficient swing distance to reach the anterior branch of the axillary nerve in all 10 specimens, with only 4 specimens having adequate long head branch swing distances. CONCLUSIONS: It is anatomically feasible to transfer multiple branches of the radial nerve supplying the medial, lateral, and sometimes, long head of the triceps to all branches of the axillary nerve in an attempt to reinnervate the deltoid and teres minor muscles. CLINICAL RELEVANCE: Understanding the axon counts of the different possible transfer combinations will improve operative flexibility and enable peripheral nerve surgeons to reinnervate for both abduction and external rotation with the highest donor/recipient axon count ratios.