Biomechanical comparison of elbow stability constructs

BACKGROUND

Despite surgical stabilization of complex elbow trauma, additional fixation to maintain joint congruity and stability may be required. Multiple biomechanical constructs include a static external fixator (SEF), a hinged external fixator (HEF), an internal joint stabilizer (IJS), and a hinged elbow orthosis (HEO). The optimal adjunct fixation to surgical reduction is yet to be determined.

METHODS

Eight matched cadaveric upper extremities were tested in a biomechanical model. Anteroposterior stress radiographs were obtained of the elbow in full supination at 0° and 45° of elbow flexion with the weight of the hand serving as a varus load as the baseline. A 360° capsuloligamentous soft-tissue release was performed around the elbow. The biomechanical constructs were applied in the same sequential order: SEF, HEF, IJS, and HEO. For each construct, 0 kg (0-lb) and 2.3 kg (5-lb) of weight were applied to the distal arm. At both weights, radiographs were obtained with the elbow at 0° and 45° of flexion, with subsequent measurement of displacement, congruence at the ulnohumeral joint, and the ulnohumeral opening angle. Statistical analysis was performed to quantify the strength and stability of each construct.

RESULTS

Compared with the control group at 0° with and without 2.3 kg (5-lb) of varus force and at 45° with and without 2.3 kg (5-lb) of varus force, no difference was noted in the medial ulnohumeral joint space, lateral ulnohumeral joint space, or ulnohumeral opening angle between the SEF, HEF, and IJS. The gap change after exertion of a 2.3-kg (5-lb) force between the control condition and application of each construct demonstrated no difference between the SEF, HEF, and IJS. Comparison among destabilized elbows showed no significant difference between the SEF, HEF, and IJS. The HEO catastrophically failed in each position at 0 kg (0-lb) of weight.

CONCLUSION

The SEF, HEF, and IJS are neither superior nor inferior at maintaining elbow congruity with the weight of the arm and 2.3 kg (5-lb) of varus stress. The HEO did not provide additional stability to the unstable elbow.

Does Undergoing Outpatient Hand Surgery Lead to Prolonged Opioid Use? A Comparison of Surgical and Nonsurgical Patients

BACKGROUND

Orthopedic surgical patients in general have been found to be at higher risk for developing opioid dependence in the postoperative period. However, there is conflicting evidence in the literature whether opioid exposure after hand surgery leads to prolonged use. In the absence of a nonoperative control group, it is not clear whether prolonged opioid use in hand surgical patients is related to undergoing a surgical intervention. The purpose of our study to compare opioid prescription fulfillment patterns in surgical and nonoperative patients in a hand surgery practice.

METHODS

We retrospectively compared 320 patients that underwent elbow, wrist, and hand surgery procedures with 741 nonoperative patients treated by 2 hand surgeons. The Pennsylvania Drug Monitoring Program (PDMP), a mandatory statewide database, was used to evaluate the primary outcomes of filling more than one opioid prescription and filling opioid prescriptions beyond 6 months of the index surgery or clinic visit. Bivariate and multivariable logistic regression analysis was performed using the following variables: surgery, prior benzodiazepine use, and prior opioid use.

RESULTS

There was no difference in prior opioid use (15.2% vs 16.9%, P = .51) or prior benzodiazepine (10.4% vs 8.4%, P = .33) use between the nonoperative and operative groups. Patients that underwent surgery had a higher incidence of filling more than one opioid prescription (20.9% vs 8.8%, P < .001). However, continued opioid use was not statistically different between nonoperative and operative patients (2.8% vs 5%, P = .08). Bivariate analysis demonstrated that prior opioids (odds ratio [OR] = 12.94, P < .001) and prior benzodiazepines (OR = 1.95, P < .001) were significant independent risk factors for prolonged opioid use. Multivariable analysis demonstrated prior opioid use to be the only independent risk factor for prolonged opioid use (OR = 12.58, P < .001).

CONCLUSION

Undergoing outpatient hand surgery do not appear to be an independent risk factor for filling opioid prescriptions beyond 6 months. Significant risk factors for prolonged opioid use include prior use of controlled substances, particularly prior opioid use.

Efficacy of Waterproof Cast Protectors and Their Ability to Keep Casts Dry

PURPOSE

The purpose of the study was to compare the efficacy of 6 different commercially available waterproof cast protectors in their ability to maintain a dry environment and evaluate whether cast protectors perform better than a plastic bag secured with tape in keeping casts dry.

METHODS

We enrolled 23 adult participants to test 6 different commercially available cast protectors and a plastic bag. Participants trialed all cast protectors twice, with and without motion, by fully submerging each cast protector in water with a paper towel held between their index and middle fingers. Moisture accumulation within the cast protectors was estimated by the change in weight of paper towel. An analysis of variance test was performed to compare differences between cast protectors in their ability to maintain a dry internal environment.

RESULTS

The plastic bag showed an average moisture accumulation of 5.50 g without motion compared with all other cast protectors, which had 0.0 g of moisture accumulation. One cast protector and the plastic bag had an average moisture accumulation of 0.46 g and 4.51 g with motion compared to all other cast protectors. The plastic bag was ranked the worst by 100% of participants.

CONCLUSION

Cast protectors appear to offer superior protection from moisture compared with a plastic bag.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Contactless Remote 3D Splinting during COVID-19: Report of Two Patients

We used calibrated 2D images uploaded by patients to an online platform to generate a 3D digital model of the limb. This was used to 3D print a splint. This method of 3D printing of splints was used for two patients who were not able to visit the hospital in person due to restrictions placed by the COVID-19 pandemic. Both patients were satisfied with the splint. We feel that this technology could be used to offer additional options to conventional splinting that allows contactless splint fitting. Level of Evidence: Level V (Therapeutic).

Optimal Position of the Suture Button Suspensionplasty (TightRope) for Thumb Basal Joint Arthritis

Background: Surgical treatment of basal joint arthritis commonly consists of trapeziectomy followed by various suspensionplasty techniques to provide stability to the thumb ray. Our study goal was to assess the motion and stability of the thumb ray after trapeziectomy and placement of a suture button (Mini TightRope®, Arthrex, Naples, Florida) in a high- or low-angle trajectory. We hypothesized that a low-angle trajectory would yield the greatest stability while providing maximal motion of the thumb. Methods: Eleven fresh-frozen cadaver arms were imaged fluoroscopically in anterior-posterior and lateral views before and after trapeziectomy, and after placement of low- and high-angle suture buttons. The intermetacarpal angle between the thumb and index metacarpals was measured after application of a standard force. Radial abduction, opposition, subsidence, palmar abduction, adduction, and subsidence were measured. Results: Compared to posttrapeziectomy constructs, low- and high-angle TightRope constructs demonstrated less subsidence, low-angle TightRopes had less palmar abduction, and high-angle TightRope constructs had less radial abduction and adduction. High-angle TightRopes allowed more palmar abduction than low-angle constructs. The high-angle TightRopes trended toward more subsidence than low-angle constructs, although it was not significant. Conclusions: Both TightRope constructs provided improved axial stability after trapeziectomy while not excessively limiting any one motion of the thumb. Compared to the high-angle trajectory, the low-angle TightRope placement provided a more stable construct with respect to subsidence and angular motion. Given the concern for excessive motion of the first metacarpal base with the high-angle construct, we recommend a low-angle trajectory TightRope placement.

The Effects of Distal Pole Scaphoid Resection on Wrist Biomechanics

BACKGROUND

Distal pole scaphoid resection (DPSR) is an effective way to manage chronic scaphoid non-union with limited degenerative arthritis. Studies have reported positive results in terms of pain relief, wrist range of motion and grip strength, and patient satisfaction. However, the biomechanical consequences of DPSR remain unclear. This study evaluates the effects of DPSR on carpal mechanics by assessing changes in radiographic parameters with varying quantities of scaphoid removal.

METHODS

Six fresh frozen cadaveric upper extremities were used. Resections of 25%, 50%, and 75% of the length of each scaphoid were performed under fluoroscopic image guidance. For the intact scaphoid and each resection level, the following radiographic parameters were assessed: radiolunate and capitolunate angles; carpal height and first metacarpal subsidence ratios, and ulnar carpal translation. Measurements were then repeated for grip and pinch as well as radial and ulnar wrist deviation positions. Radial styloid to trapezium distance in wrist radial deviation was also measured to assess for impingement.

RESULTS

There was a statistically significant increase in the mean radiolunate angle with increasing scaphoid resection quantities. No statistically significant correlations were found between radial styloid clearance and increasing scaphoid resection percentages. Changes in the remaining variables did not reach statistical significance.

CONCLUSION

Increasing levels of scaphoid resection is associated with progressive signs of carpal malalignment best depicted by increasing radiolunate angles. Diminishing radial styloid clearance was clinically evident as more scaphoid was resected. For this, prophylactic radial styloidectomy may be considered to avoid bony impingement.

Scaphotrapezoid Assessment during Thumb Carpometacarpal Arthroplasty: A Cadaveric Study

Background  Due to limited sensitivity of radiographs for scaphotrapeziotrapezoid (STT) arthritis and the high rate of concurrence between thumb carpometacarpal (CMC) and STT arthritis, intraoperative visualization of the STT joint is recommended during CMC arthroplasty. Purpose  We quantified the percentage of trapezoid facet of the scaphotrapezoid (ST) joint that could be visualized during this approach, and compared it to the degree of preoperative radiographic STT arthritis. Methods  We performed dorsal surgical approach to the thumb CMC joint after obtaining fluoroscopic anteroposterior, lateral, and oblique wrist radiographs of 11 cadaver wrists. After trapeziectomy, the ST joint was inspected and the visualized portion of the trapezoid articulation marked with an electrocautery. The trapezoid was removed, photographed, and the marked articular surface area and total surface area were independently measured by two authors using an image analysis software. The radiographs were analyzed for the presence of STT arthritis. Results  The mean visualized trapezoid surface area during standard approach for CMC arthroplasty was 60.3% (standard deviation: 24.6%). The visualized percentage ranged widely from 16.7 to 96.5%. There was no significant correlation between degree of radiographic arthritis and visualized percentage of the joint ( p  = 0.77). Conclusions:  On average, 60% of the trapezoid joint surface was visualized during routine approach to the thumb CMC joint, but with very large variability. Direct visualization of the joint did not correlate with the degree of radiographic STT arthritis. Clinical Relevance  A combination of clinical examination, pre- and intraoperative radiographs, and intraoperative visualization should be utilized to assess for STT osteoarthritis and determine the need for surgical treatment. Level of Evidence  This is a Cadaveric Research Article.

Overall Opioid Consumption Is Not Associated With the Amount of Opioids Administered and Prescribed on the Day of Upper Extremity Surgery

Background: Orthopedic surgeons need to better understand the effect their opioid-prescribing habits have on patients. The purpose of our study was to evaluate whether the type of procedure or initial amount of opioids prescribed postoperatively leads to increased consumption of opioids. Methods: Consecutive patients undergoing upper extremity surgery were enrolled. The medical record and Pennsylvania Prescription Drug Monitoring Program Web site were used to record all prescriptions of controlled substances consumed intraoperatively, in the recovery room, and in prescriptions filled 6 months postoperatively. Morphine equivalent units (MEUs) were used to quantify the amount of opioids. Results: Two hundred ninety patients were included in the study. The mean MEU administered intraoperatively was 25.1 (0-50). The MEU provided in the recovery room was 2.9 (0-60). The MEU prescribed on the day of surgery was 155.6 (137-178). We used the Pearson correlation coefficient of r = 0, meaning no/weak correlation, and r = 1, meaning a strong correlation. Neither MEUs provided intraoperatively or in recovery, nor MEUs prescribed postoperatively correlated with prescriptions filled (r = 0.13, 0.02, 0.09, respectively). Although patients undergoing bony procedures were prescribed more opioids (P < .001), opioid consumption intraoperatively, in recovery, and in prescriptions filled was not significantly different. Conclusions: The MEUs administered and prescribed on the day of surgery did not affect the amount of prescriptions filled postoperatively. Finally, patients undergoing bony procedures were prescribed more opioids than those undergoing soft tissue procedures, but they did not consume or fill more opioids postoperatively.

Three Dimensionally Printed Versus Conventional Casts in Pediatric Wrist Fractures

Background and objective With significant advancement in the field of biomaterials, alternatives to conventional fiberglass casts such as customized three-dimensional (3D) orthotics have been developed. However, there is a scarcity of reported experience regarding 3D-printed orthoses. The purpose of this study was to compare radiographic outcomes and patient satisfaction with fractures treated with either conventional or 3D-printed casts. Materials and methods We included 23 limbs from 22 patients, who were aged between 8-18 years, and with a diagnosis of an acute nondisplaced wrist or forearm fracture. Patients were randomized into two groups: consisting of those treated with a 3D-printed orthosis and those with conventional fiberglass cast. Outcomes included X-ray alignment and healing, cast fit, the appearance of the skin, ease of care, and overall satisfaction. Results Of note, 10/11 (91%) in the 3D cast group healed in an excellent position, and 1/11 healed in an acceptable position. Also, 11/12 (92%) in the conventional cast group healed in an excellent position, and 1/12 healed in an acceptable position. Radiographically, 11/11 (100%) of the fractures in the 3D group and 11/12 (92%) in the conventional cast group were found to be fully healed. No differences were found in terms of skin irritation by a blinded hand therapist. Patients reported significant differences in skin irritation, comfort, satisfaction, and cast care favoring 3D casts (p<0.05). Conclusions 3D orthoses offer a promising opportunity to improve patients' experiences with upper extremity casting while also providing appropriate immobilization.

Time to Improvement After Corticosteroid Injection for Trigger Finger

Purpose

Trigger finger is a commonly occurring hand condition that presents with symptoms of pain, clicking, locking, and catching of the finger. A common non-operative management option is corticosteroid injection. The purpose of this study was to evaluate the short-term patient response to corticosteroid injections for trigger finger. 

Methods

The patients of six fellowship-trained orthopedic hand surgeons who underwent a corticosteroid injection for trigger finger between June 2019 and October 2019 were invited to participate in this study. Patients were contacted by phone at one week, two weeks, and three weeks after the injection to complete a questionnaire regarding their pain and triggering symptoms. Medical records were also reviewed to collect basic demographic data.

Results

A total of 452 patients were included in the study. At the final follow-up, 82.4% of patients reported complete pain relief, 16.3% had partial relief, and 1.2% had no relief from their pain. For their triggering symptoms, 65.9% reported complete triggering relief, 30.4% had partial relief, and 3.5% had no triggering relief. It took an average of 6.6 days following injection for patients to experience complete pain relief, and an average of 8.1 days for patients to experience complete triggering relief.

Conclusions

This analysis found that most patients experience relief of pain and triggering at three weeks following corticosteroid injection. The majority of patients experienced some pain relief within the first week following corticosteroid injection, while improvement in triggering appeared to lag behind pain relief.

An Evaluation of the Bacterial Adherence to Casting Materials

Introduction: The purpose of this study was to evaluate bacterial adherence to common casting materials including plaster of Paris (plaster), fiberglass, three-dimensional (3D) printed plastic, and silicone-coated 3D printed plastic.

Methods: The minimal inhibitory concentration of a phosphate-free detergent (Palmolive) needed to achieve total bacterial kill off was determined. 3D printed polylactic acid plastic samples were coated with silicone. Plaster, fiberglass, plastic, and silicone-coated plastic samples were inoculated with Staphylococcus aureus. After bacterial inoculation, scanning electron microscopy of the samples was performed to visualize bacterial adherence to the materials' surface. Using either sterile water or a 5% detergent solution, the materials were subjected to washings. Each material was run in 30 replicates: 6 without washing, 6 with sterile water for 1 minute, 6 with detergent for 1 minute, 6 with sterile water for 3 minutes, and 6 with detergent for 3 minutes. The replicates that did not undergo a washing trial represented the initial bacterial inoculation. Samples were then rinsed and sonicated in polysorbate to isolate the remaining adherent bacteria on the materials’ surface. The sonicated solutions were plated, incubated, and counted for quantification of colony forming units (CFU) of bacteria. This protocol was repeated for a total of four trials.

Results: During inoculation, there were significantly less bacteria that adhered to silicone-coated 3D printed plastic (58879 CFU) compared to plastic (217479 CFU), plaster (140063 CFU), and fiberglass (550546 CFU). Silicone coating showed further superiority. Silicone-coated 3D printed plastic was able to be decontaminated as demonstrated by significantly fewer remaining bacteria (9.3%) on its surface after being washed with a 5% detergent solution (1797 CFU) compared to sterile water (19321 CFU). The mean remaining bacteria on silicone-coated 3D printed plastic was significantly less than that remaining on all other materials when washed with either sterile water or a detergent solution for both durations of 1 minute and 3 minutes.

Conclusions: The current study demonstrates that significantly less bacteria adhere to the surface of 3D printed plastic with silicone coating showing added protection and that this material can be decontaminated to a greater degree with washing than conventional casting materials. These results provide evidence that 3D printed casts can be washed and successfully decontaminated during a patient’s period of immobilization, which is advantageous especially during an infectious crisis such as the coronavirus disease 2019 (COVID-19) pandemic.

Mechanisms of reducing joint stiffness by blocking collagen fibrillogenesis in a rabbit model of posttraumatic arthrofibrosis

Posttraumatic fibrotic scarring is a significant medical problem that alters the proper functioning of injured tissues. Current methods to reduce posttraumatic fibrosis rely on anti-inflammatory and anti-proliferative agents with broad intracellular targets. As a result, their use is not fully effective and may cause unwanted side effects. Our group previously demonstrated that extracellular collagen fibrillogenesis is a valid and specific target to reduce collagen-rich scar buildup. Our previous studies showed that a rationally designed antibody that binds the C-terminal telopeptide of the α2(I) chain involved in the aggregation of collagen molecules limits fibril assembly in vitro and reduces scar formation in vivo. Here, we have utilized a clinically relevant arthrofibrosis model to study the broad mechanisms of the anti-scarring activity of this antibody. Moreover, we analyzed the effects of targeting collagen fibril formation on the quality of healed joint tissues, including the posterior capsule, patellar tendon, and subchondral bone. Our results show that blocking collagen fibrillogenesis not only reduces collagen content in the scar, but also accelerates the remodeling of healing tissues and changes the collagen fibrils’ cross-linking. In total, this study demonstrated that targeting collagen fibrillogenesis to limit arthrofibrosis affects neither the quality of healing of the joint tissues nor disturbs vital tissues and organs.

Recurrence of Ganglion Cysts Following Re-excision

Background

The recurrence of ganglion cysts after surgical excision has a reported rate of 4% to 40%. Recurrence rate after revision surgical excision is unknown. The purpose of this study was to define the incidence of recurrent ganglion cysts in patients who underwent a secondary excision procedure.

Methods

With Institutional Review Board approval, we retrospectively identified by CPT code and reviewed charts of patients who had recurrent ganglion cyst excision performed over a five-year period (2010 - 2014). Recurrence was defined as reappearance of a cyst in the same area as it was previously. Demographic information including recurrences and revision surgeries was collected in addition to outcome variables such as patient satisfaction, pain levels, and functional limitations.

Results

Out of the 42 revision cases identified 20 patients were reached. Mean time to recurrence of the cyst after the first ganglion cyst excision was 2.5 years (range: 1 month - 12 years). After the second ganglion cyst excision, three patients (15%) had a recurrence, each occurring within one year (mean: 11 months; range: 9-12). One of the three patients underwent a third successful ganglion cyst excision. The other two patients declined surgical intervention to date. Patients without a second recurrence (n=17) reported an average pain score of 0.1 (range: 0-2) on a scale of 1-10. Three (18%) reported some difficulty with day-to-day activities due to their scar. Seven (41%) patients reported at least transient numbness or tingling. Mean satisfaction was 9.8 on a scale of 1-10, and 100% reported that they would undergo another ganglion cyst excision should they ever have another recurrence.

Conclusion

Patients should be advised about the risk of recurrence after re-excision of ganglion cysts, which was noted to be 15% in our cohort. This rate of recurrence is similar to that of primarily excised cysts.

The Accuracy of 3D Printed Carpal Bones Generated from Cadaveric Specimens

Background

Computer assisted three-dimensional (3D) printing of anatomic models using advanced imaging has wide applications within orthopaedics. The purpose of this study is to evaluate the 3D printing accuracy of carpal bones.

Methods

Seven cadaveric wrists underwent CT scanning, after which select carpal bones (scaphoid, capitate, lunate, and trapezium) were dissected in toto. Dimensions including length, circumference, and volume were measured directly from the cadaver bones. The CT images were converted into 3D printable stereolithography (STL) files. The STL files were converted into solid prints using a commercially available 3D printer. The 3D printed models' dimensions were measured and compared to those of the cadaver bones. A paired t-test was performed to determine if a statistically significant difference existed between the mean measurements of the cadavers and 3D printed models. The intraclass correlation coefficients (ICC) between the two groups were calculated to measure the degree of agreement.

Results

On average, the length and circumference of the 3D printed models were within 2.3 mm and 2.2 mm, respectively, of the cadaveric bones. There was a larger discrepancy in the volume measured, which on average was within 0.65 cc (15.9%) of the cadaveric bones. These differences were not statistically significant (P > 0.05). There was strong agreement between all measurements except the capitate's length and lunate's volume.

Conclusion

3D printing can add value to patient care and improve outcomes. This study demonstrates that 3D printing can both accurately and reproducibly fabricate boney models that closely resemble the corresponding cadaveric anatomy.

Patient Perceptions of COVID-19 Precautions and Their Effects on Experiences With Hand Surgery

Purpose

The purpose of this study is to evaluate patient perceptions of COVID-19 precautions and how these precautions have affected their hand and upper extremity surgery experience.

Methods

We sent an 18-item survey to 1,213 patients who underwent elective hand and upper extremity surgery at 1 academic institution from October 2020 to January 2021. The survey consisted of questions related to patient demographics, treatment delays due to COVID-19, and patient perceptions of COVID-19 precautions. Descriptive statistics were performed to analyze the survey responses. Responses for patients aged 18–50 and 51+ were compared using a chi-square analysis for categorical variables and a Student t-test for continuous variables.

Results

Out of 1,213 invitations, 384 survey respondents completed the survey (31.6%). Of the respondents, 16.8% reported delaying medical treatment for an average of 123.2 days because of COVID-19. The preventative measures were found to be adequate by 95% of patients. Only 2.6% of patients reported experiencing surgical delays due to preoperative COVID-19 testing or other COVID-19-related precautions. COVID-19 testing was seen as necessary by 88% of patients, and 74% did not find COVID-19 testing to be a barrier to their surgery. Patients aged 51+ were more likely to delay seeking medical treatment than younger patients (19.3% vs 9.1%, respectively). Furthermore, those that did delay seeking treatment waited longer on average than their younger counterparts (136.1 vs 72.9 days, respectively).

Conclusions

In conclusion, patients undergoing hand and upper extremity surgery typically do not find COVID-19 precautions to be a significant barrier to care and understand their importance. Despite this, many patients, particularly older ones, are delaying medical care for extended periods of time. It is important for hand surgeons to acknowledge their patients’ perspectives and work to educate patients on evolving surgical safety guidelines.

Clinical relevance

Patient perspectives of current COVID-19 precautions can help inform hand surgeons on areas for continued patient education.

The Use of 3D Printed Customized Casts in Children with Upper Extremity Fractures: A Report of Two Cases

3D printing is an evolving technology which has a potential application in the treatment pediatric forearm fractures. Very little has been published with regard to 3D casting in children. We present two cases in which upper extremity fractures in pediatric patients were treated by wearing a custom made 3D printed cast. At latest follow-up at least one year post-injury, the clinical outcomes were excellent. Orthopaedic surgeons may benefit from familiarizing themselves with the potential of 3D printing technology and utilizing its current applications, as well as devising future applications, in clinical practice.

Sterility of Ethyl Chloride Spray After Use in the Clinic

Background: Ethyl chloride spray is used frequently in the outpatient setting as a local anesthetic for injections and aspirations with varying consensus about the sterility of the spray. We hypothesize that ethyl chloride spray remains sterile and would show no bacterial growth during routine clinical use. Methods: Thirteen ethyl chloride bottles were collected for testing. Two unopened bottles were used as controls. Eleven unopened bottles were placed in orthopedic clinics and recollected after varying duration of use. The final volume and duration of use were recorded. Each bottle was sprayed in a separate test tube and allowed to evaporate. Trypticase soy broth was added to each tube and incubated for 48 hours. Control test tubes with broth alone were prepared and incubated under the same conditions. Cultures were evaluated at 24 and 48 hours. Results: The mean duration of ethyl chloride bottle use prior to culturing was 26 days. The average volume used per day was 1.9 mL. Each ethyl chloride bottle had an initial volume of 103.5 mL. Using the average daily volume usage, an extrapolated lifespan of each bottle was estimated at 7.7 weeks. None of the samples showed bacterial or fungal growth at 24 or 48 hours. Conclusion: Ethyl chloride bottles used in the clinical settings showed no bacterial or fungal contamination through their shelf life and routine use. The duration and amount of use did not affect sterility. Although the antimicrobial activity of ethyl chloride spray on skin is debated, ethyl chloride itself remains sterile through clinical use.

An Evaluation of Complications Following Ultrasound-Guided Regional Block Anesthesia in Outpatient Hand Surgery

Background: Ultrasound-guided (USG) assistance has contributed to the acceptance of regional anesthesia as a safe and efficient alternative to traditional general anesthesia. However, limited data exist regarding the safety of supraclavicular blocks used in common hand surgery procedures. The purpose of this retrospective study was to evaluate a large sample of cases to determine the effectiveness and complication rate of supraclavicular nerve blocks and confirm the safety of its use within the ambulatory surgery center (ASC) setting. Methods: Nerve blocks for the upper extremity were performed via the supraclavicular approach using the USG technique. Records were analyzed for all patients monitored during the immediate postoperative recovery and step-down phases at the ASC and contacted by phone or evaluated within 2 weeks at their first postoperative visit. Adverse outcomes related to the regional block anesthesia were identified via phone interview or postoperative surgical visit and documented. Results: In all, 713 records were reviewed with 56% female (n = 398) and 44% male (n = 315) patients. Of the 713 cases, 4 adverse events were identified (0.6%, 95% confidence interval [%]), including 2 abnormal reactions to the nerve block and 2 incomplete blocks with inadequate pain control. Conclusions: This study is the first report to evaluate a large sample of outpatient hand procedures at a high-volume ASC. We can report no clinically significant pulmonary or neurovascular complications with the use of USG supraclavicular nerve block techniques, further supporting its establishment as a safe and efficient procedure, yielding a low complication rate.

Low Rate of Complications Following Intramedullary Headless Compression Screw Fixation of Metacarpal Fractures

Background: There has been a recent increase in the use of headless compression screws for fixation of metacarpal neck and shaft fractures as they offer several advantages, and minimal complications have been reported. This study aimed to evaluate the clinical complications and their solutions following retrograde intramedullary headless compression screw fixation of metacarpal fractures. We describe complications and the approach to their management. Methods: We performed a multicenter case series through retrospective review of all patients treated with intramedullary headless screw fixation of metacarpal fractures by 3 fellowship-trained hand surgeons. Patient demographics, implant used, type of complication, pre- and postoperative radiographs, operative reports, and sequelae were reviewed for each case. We defined complications as infection, loss of fixation, hardware failure, malrotation, nonunion, malunion, metal allergy, and any repeat surgical intervention. Results: Four complications (2.5%) were identified through the review of 160 total metacarpal fractures. One complication was a nickel allergy, one was a broken screw after repeat trauma, and 2 patients had bent intramedullary screws. Screw removal in 3 patients was simple and without complications or persistent limitations. One bent screw with a refracture was left in place. No serious complications were seen. Conclusion: Intramedullary screw fixation of metacarpal fractures is safe with a low incidence of complications (2.5%) that can be safely and effectively managed.

Ultrasound Evaluation for Incomplete Carpal Tunnel Release

Background: Ultrasound can provide evaluation of the anatomy of the carpal tunnel in a convenient, noninvasive office setting. This study is intended to determine the accuracy and diagnostic performance of ultrasound, used by surgeons, for the evaluation of completeness of carpal tunnel release (CTR). Methods: Ten cadaver arms underwent randomized sectioning of 0%, 25%, 50%, 75%, or 100% of the transverse carpal ligament. Following a brief training session, a blinded observer used ultrasound to evaluate the percentage of the transverse carpal ligament release. The release amount was then confirmed with an open exposure of the transverse carpal ligament. Results: Cronbach α and Pearson correlation coefficients were 0.92 and 0.87, demonstrating excellent reliability and validity of the technique. Diagnostic performance including sensitivity, specificity, positive predictive value, and negative predictive value was 100%, 75%, 86%, and 100%, respectively, for the diagnosis of incomplete release of the transverse carpal ligament by a novice sonographer orthopedic surgeon. Conclusions: The ultrasound is a highly accurate tool for the diagnosis of incomplete transverse carpal ligament release and requires a minimal amount of training to use for this purpose. It provides a rapid means of diagnosing incomplete release of the transverse carpal ligament following CTR.

Collagen-rich deposit formation in the sciatic nerve after injury and surgical repair: A study of collagen-producing cells in a rabbit model

INTRODUCTION

Posttraumatic scarring of peripheral nerves produces unwanted adhesions that block axonal growth. In the context of surgical nerve repair, the organization of the scar tissue adjacent to conduits used to span the gap between the stumps of transected nerves is poorly understood. The goal of this study was to elucidate the patterns of distribution of collagen-rich scar tissue and analyze the spatial organization of cells that produce fibrotic deposits around and within the conduit's lumen.

METHODS

Employing a rabbit model of sciatic nerve transection injury, we studied the formation of collagen-rich scar tissue both inside and outside conduits used to bridge the injury sites. Utilizing quantitative immunohistology and Fourier-transform infrared spectroscopy methods, we measured cellular and structural elements present in the extraneural and the intraneural scar of the proximal and distal nerve fragments.

RESULTS

Analysis of cells producing collagen-rich deposits revealed that alpha-smooth muscle actin-positive myofibroblasts were only present in the margins of the stumps. In contrast, heat shock protein 47-positive fibroblasts actively producing collagenous proteins were abundant within the entire scar tissue. The most prominent site of transected sciatic nerves with the highest number of cells actively producing collagen-rich scar was the proximal stump.

CONCLUSION

Our findings suggest the proximal region of the injury site plays a prominent role in pro-fibrotic processes associated with the formation of collagen-rich deposits. Moreover, they show that the role of canonical myofibroblasts in peripheral nerve regeneration is limited to wound contracture and that a distinct population of fibroblastic cells produce the collagenous proteins that form scar tissue. As scarring after nerve injury remains a clinical problem with poor outcomes due to incomplete nerve recovery, further elucidation of the cellular and spatial aspects of neural fibrosis will lead to more targeted treatments in the clinical setting.

Telemedicine Evaluation and Techniques in Hand Surgery

The demand for telemedicine has been increasing over the past several years with the growth of technology and digital connectivity in our daily lives. With the impact of the global coronavirus disease 2019 pandemic, telemedicine implementation has become a necessity for many specialties because social distancing measures have greatly affected access to routine medical care. This article presents a detailed and systematic approach to conducting a hand physical examination during a video telemedicine encounter. Although the telemedicine physical examination has limitations, most components of the normal physical examination can be completed remotely with a systematic approach. We enumerate modifications to maximize examination remotely and present considerations for improved delivery of telemedicine care. These methods may be beneficial to providers incorporating telemedicine into their practice.

Safety and Efficacy of Casting during COVID-19 Pandemic: A Comparison of the Mechanical Properties of Polymers Used for 3D Printing to Conventional Materials Used for the Generation of Orthopaedic Orthoses

To reduce the risk of spread of the novel coronavirus (COVID-19), the emerging protocols are advising for less physician-patient contact, shortening the contact time, and keeping a safe distance. It is recommended that unnecessary casting be avoided in the events that alternative methods can be applied such as in stable ankle fractures, and hindfoot/midfoot/forefoot injuries. Fiberglass casts are suboptimal because they require a follow up for cast removal while a conventional plaster cast is amenable to self-removal by submerging in water and cutting the cotton bandages with scissors. At present, only fiberglass casts are widely available to allow waterproof casting. To reduce the contact time during casting, a custom-made 3D printed casts/splints can be ordered remotely which reduces the number of visits and shortens the contact time while it allows for self-removal by the patient. The cast is printed after the limb is 3D scanned in 5-10 seconds using the commercially available 3D scanners. In contrast to the conventional casting, a 3D printed cast/splint is washable which is an advantage during an infectious crisis such as the COVID-19 pandemic.

Predictive Factors for Return to Driving following Volar Plate Fixation of Distal Radius Fracture

Background  A common query by patients undergoing distal radius fracture (DRF) repair is when (s)he can resume driving postoperatively. A prospective cohort analysis was performed to assess fracture and patient factors on a patient's self-reported ability to return to driving to better inform patients and surgeons. Methods  Consecutive patients undergoing DRF repair with locking volar plate were enrolled. Preoperative demographic and radiographic characteristics, and postoperative time to return to driving were collected. Data collected included age, sex, hand dominance, body mass index (BMI), level of education, concomitant ulnar fracture, fracture setting prior to surgery, and AO fracture classification. Results  A total of 131 patients were enrolled (108 women, 23 men) with 36 AO type A, 22 AO type B, and 73 AO type C DRFs, with an average age of 59.5 years. Fracture severity by classification did not significantly affect time to return to driving. However, BMI, sex, and age were found to significantly affect time to return to driving. Patients aged 19 to 59 years, 60 to 75 years, and over 75 years returned to driving 13.1, 15.4, and 30.1 days following surgery, respectively ( p  < 0.01). Classified by BMI, patients that were normal weight, overweight, and obese returned to driving 11.5, 13.1, and 21.0 days following surgery, respectively ( p  < 0.05). Men returned to driving 8.8 days and women 17.3 days postoperatively ( p  = 0.001). Conclusion  Patients severity of fracture as determined by AO fracture type did not affect time to driving, while increased BMI, female sex, and increased age were found to be significant factors in patients' return to driving time after distal radius fracture repair. Level of Evidence  This is a Level II, prospective cohort study.