Favorable short-term outcomes of micronized allogenic cartilage scaffold for glenoid cartilage defects associated with posterior glenohumeral instability.

Purpose: To determine clinical outcomes associated with micronized allogenic cartilage scaffold use for treatment of posterior glenoid cartilage defects at 2 years. Study Design: Case series. Methods: A retrospective analysis of prospectively collected data was performed on a consecutive series of patients who underwent arthroscopic treatment of a symptomatic posterior glenoid cartilage defect with micronized allogenic cartilage scaffold between January 2019 and December 2020. The primary outcome was subjective shoulder value (SSV) at latest follow-up. Secondary outcomes included visual analog scale (VAS), recurrence of instability, and range of motion (ROM). Results: Seven patients, including 4 in the setting of primary posterior instability and 3 in the setting of recurrent symptoms after arthroscopic posterior glenohumeral stabilization, were included in the analysis with a mean follow up of 2.6 years (range, 2-3.7 years). Statistically significant improvements were seen in SSV (median = 40, interquartile range [IQR] = 40-50 before surgery; vs median = 85, IQR = 67.5-87.5 after surgery; P = .018) and VAS (median = 4, IQR = 4-6.3 before surgery; vs median = 1, IQR = 0-1.5 after surgery; P = .010). No significant differences were seen in ROM. There were no cases of recurrent instability or reoperation. Conclusions: The use of micronized allogenic cartilage scaffold for glenoid cartilage defects is associated with clinical improvement at 2-year follow-up. This is the case when performed in conjunction with index posterior labral repair when there is a concomitant glenoid cartilage defect or when performed in the setting of persistent pain and mechanical symptoms after prior posterior labral repair. Level of Evidence: Level IV, therapeutic case series.

Hounsfield Unit-Calculated Bone Mineral Density Loss Following Combat-Related Lower Extremity Amputations.

BACKGROUND: After combat-related lower extremity amputations, patients rapidly lose bone mineral density (BMD). As serial dual x-ray absorptiometry (DXA) scans are rarely performed in this setting, it is difficult to determine the timeline for bone loss and recovery or the role of interventions. However, a strong correlation has been demonstrated between DXA BMD and computed tomography (CT) signal attenuation. We sought to leverage multiple CT scans obtained after trauma to develop a predictive model for BMD after combat-related lower extremity amputations. METHODS: We reviewed amputations performed within the United States military between 2003 and 2016 in patients with multiple CT scans. We collected pertinent clinical information, including amputation level(s), complications, and time to weight-bearing. The primary outcome measure was the development of low BMD, estimated in Hounsfield units (HU) from CT scans with use of a previously validated method. One hundred and twenty-eight patients with 613 femoral neck CT scans were available for analysis. A least absolute shrinkage and selection operator (LASSO) multiple logistic regression analysis was applied to determine the effects of modifiable and non-modifiable variables on BMD. A random-effects model was applied to determine which factors were most predictive of low BMD and to quantify their effects. RESULTS: Both amputated and non-amputated extremities demonstrated substantial BMD loss, which stabilized approximately 3 years after the injury. Loss of BMD followed a logarithmic pattern, stabilizing after 1,000 days. On average, amputated limbs lost approximately 100 HU of BMD after 1,000 days. Other factors identified by the mixed-effects model included nonambulatory status (-33.5 HU), age at injury (-3.4 HU per year), surgical complications delaying weight-bearing (-21.3 HU), transtibial amputation (20.9 HU), and active vitamin-D treatment (-19.7 HU). CONCLUSIONS: Patients with combat-related lower extremity amputations experience an initially rapid decline in BMD in both intact and amputated limbs as a result of both modifiable and non-modifiable influences, including time to walking, amputation level, surgical complications, and age. The paradoxical association of vitamin-D supplementation with lower HU likely reflects this treatment being assigned to patients with low BMD. This model may assist with clinical decision-making prior to performing lower extremity amputation and also may assist providers with postoperative decision-making to optimize management for prophylaxis against osteoporosis. LEVEL OF EVIDENCE: Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence.

Utilization of a Clinic-Based Hand Surgery Procedure Room in the US Military Health System: A Performance Improvement Analysis of Resource Savings and Patient Satisfaction.

PURPOSE: Recent studies examining the implementation of clinic-based procedure rooms (PRs) for wide-awake hand surgery have reported cost reduction, decreased burden on hospital systems, and improved patient satisfaction. This study evaluates other resource savings, primarily time spent by patients in the hospital. METHODS: Thirty-two patients were enrolled in a PR or the operating room group for prospective evaluation. Time spent in the hospital on the day of surgery, several preprocedure appointments, complications, and cost comparisons were evaluated between the two groups. Patient-reported outcomes were also evaluated with postoperative surveys assessing anxiety, pain, and satisfaction. RESULTS: Significant time savings were noted between the groups. The median time spent in the hospital on the day of surgery for the patients in the operating room group was 256 minutes versus 90 minutes for the PR group, a time savings of approximately 3 hours. Eight additional preoperative clinic visits for operating room patients were generated compared with no additional preoperative visits for PR patients. Cost savings for surgeries performed in the clinic-based procedure amounted to $232,411. No postoperative complications were observed in the clinic setting. CONCLUSIONS: Continued utilization of the clinical PR for select hand surgery procedures will reduce the cost and time burdens for procedures while maintaining satisfaction and safety. CLINICAL RELEVANCE: A clinic-based PR for performing minor hand surgeries saves the patient time and ostensibly allows the operating room to be used for more complex surgeries that are not easily amenable to a wide-awake in-clinic procedure.

Surgical and Patient-Centered Outcomes of Open versus Arthroscopic Ganglion Cyst Excision: A Systematic Review.

Introduction As the popularity of wrist arthroscopy grows, it continues to prove useful in the treatment of ganglion cysts. Previous studies comparing an arthroscopic technique to traditional open excision have demonstrated generally equivalent results regarding complications and cyst recurrence. However, this systematic review compares the two treatment methods not only regarding cyst recurrence but also regarding patient-centered outcomes. Additionally, new studies in the available literature may allow for further analysis. Methods This systematic review identified 23 articles published between 2000 and 2021 that met inclusion criteria. Articles were assessed for quality, and reported cyst recurrence rates, patient satisfaction, patients' preoperative and postoperative pain, and complications associated with either open or arthroscopic excisions were pooled into open excision and arthroscopic excision groups for analysis. Results In total, 23 studies accounted for 1,670 cases. Pooled data for patient-centered outcomes indicated a significantly higher patient satisfaction rate (89.2 vs 85.6%, p < 0.001) and higher reported pain relief (69.5 vs. 66.7%, p = 0.011) associated with arthroscopic excision versus open excision. Recurrence rates were also significantly lower for the arthroscopic excision group (9.4 vs. 11.2%, p < 0.001). Overall, the complication rate was significantly lower for arthroscopic excision (7.5 vs. 10.7%, p < 0.001), but the complication profile distinctly differed between the two methods. Conclusions Both arthroscopic and open excision of dorsal wrist ganglions are viable treatment options. However, the results of this meta-analysis suggest benefits associated with the arthroscopic technique in both patient-centered outcomes and in traditional, surgical outcomes. This may prove advantageous as wrist arthroscopy becomes more common.

Bone Morphogenic Protein-2 Use for the Surgical Treatment of Acute Scaphoid Fractures and Scaphoid Nonunions.

BACKGROUND: Bone morphogenic protein-2 has demonstrated promise as an adjunct to surgically treating fractures. Its reported use in the upper extremity is limited. This study reports union rates, outcomes, and complications of scaphoid fractures treated with adjunctive bone morphogenic protein-2 to further characterize bone morphogenic protein-2 use in the hand and wrist. METHODS: Retrospective review of scaphoid fractures treated surgically in one region of the Military Health System from 2009 to 2019 was conducted to identify cases using bone morphogenic protein-2. Fracture healing was determined by computed tomography. Primary outcomes were union rate, time to union, and complications. Secondary outcomes included union rates for prior nonunions, union rates at 4 and 6 weeks, and functional outcomes. RESULTS: Fourteen patients met inclusion criteria. Nonunions accounted for 50 percent of included fractures. The total union rate was 93 percent. Mean time to union was 6.2 weeks. All acute fractures healed with a mean time to union of 4.8 weeks. Nonunions had a union rate of 86 percent, with a mean time to union of 7.7 weeks. Four patients (29 percent) developed radiographic heterotopic ossification; however, no significant decrease in motion was appreciated. Thirteen patients (93 percent) resumed the push-ups portion of the military fitness test. No major complications were identified during follow-up. CONCLUSIONS: Adjunctive use of bone morphogenic protein-2 in operative fixation of scaphoid fractures resulted in desirable union rates without major complications. Larger, prospective studies are needed to assess whether adjunctive bone morphogenic protein-2 use in scaphoid fractures provides significant benefit compared with other treatments. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

Validation of a High-Fidelity Fracture Fixation Model for Skill Acquisition in Orthopedic Surgery Residents.

OBJECTIVE: Simulation has become a widely accepted part of training and credentialing processes due to its ability to supplement technical skill acquisition outside of the operating room (OR). This project explores implementation of a bench-top simulation of open reduction with internal fixation (ORIF) as a cost-effective method for practicing and evaluating surgical skill. DESIGN, SETTING, AND PARTICIPANTS: Participants ranging from intern to attending surgeon performed ORIF using a standard fixation set and a bovine or porcine tibia/radius model. Performance was recorded and scored by blinded reviewers based on a modified global rating scale (GRS), objective structured assessment of technical skills (OSATS) procedure-specific checklist, and critical-mistakes (CM) model. We calculated Fleiss' kappa for inter-rater reliability, Cronbach's alpha for internal consistency of scoring systems, and used univariate analysis to determine the ability of this model to discriminate between training levels. We also performed a normalized performance-versus-cost analysis to characterize perceived value of this simulation compared to other modalities. RESULTS: Twenty subjects completed the fracture fixation exercise. Fleiss' kappa for all scoring systems indicated substantial inter-rater agreement (k = 0.81, 0.80, and 0.74 for GRS, OSATS, and CM, respectively). Internal consistency reliability for GRS and OSATS were high with Cronbach's alpha 0.96(95%CI 0.94-0.97) and 0.94(95%CI 0.91-0.96), respectively. Using a Kuskal-Wallis rank sum test, GRS, OSATS, and CM were found effective for measuring differences between resident levels (p < 0.001, p < 0.001, and p = 0.002, respectively). Qualitative valuation of the exercise indicated similar value for education compared to time spent in the OR and surgical skills labs. CONCLUSIONS: This benchtop surgical simulation provides quantitative measurement of operative skills progression, increases trainee familiarity with ORIF principles, and permits targeted education by senior surgeons with the goal of training safe graduates. Procedure-specific checklist grading tools reliably differentiated between training levels with high internal validity. Implementing this model may decrease training costs and accelerate skill acquisition.

Surgical Management of Ulnar Metacarpal Base Fracture-Dislocations: A Systematic Review.

BACKGROUND: Ulnar metacarpal base fractures can destabilize the carpometacarpal (CMC) joint, prompting surgical stabilization. Studies investigating this injury are limited by small case volumes. Our purpose is to review the surgical techniques, outcomes, and complications of ulnar CMC joint stabilization. METHODS: A literature search was performed of all articles published on the surgical treatment and outcomes of ulnar CMC fracture dislocations using PubMed and Google Scholar databases between the years 2014 and 2019. Data were pooled and analyzed, assessing surgical techniques and hand outcome measures: union, recurrent dislocations, range of motion, grip strength, and complications. RESULTS: Six studies met inclusion criteria. All surgical patients, regardless of technique, went on to union with no incidents of recurrent instability. Grip strength was significantly decreased postoperatively (82.7% of uninjured side). Patients with CMC dislocations of both the fourth and fifth ray had similar postoperative outcomes to those with CMC dislocations of the fifth ray alone. One third of plate and screw constructs required plate removal, due to breakage (2) or implant-related pain (4). Plate-related symptoms resolved after removal in all cases. Delayed treatment decreased the effectiveness of nonoperative treatment, and increased the likelihood of postoperative pain, chronic deformity, malunion, and CMC osteoarthritis. CONCLUSIONS: Closed reduction percutaneous pinning, open reduction percutaneous pinning, and open reduction internal fixation with CMC joint bridging or dorsal buttress plating are all well described, safe techniques with low complication rates. Early, accurate diagnosis of fourth and fifth CMC joint fracture-dislocations is crucial for optimizing hand function and postoperative outcomes.

Biomechanical Comparison of Anatomic Restoration of the Ulnar Footprint vs Traditional Ulnar Tunnels in Ulnar Collateral Ligament Reconstruction.

BACKGROUND: Current techniques for ulnar collateral ligament (UCL) reconstruction do not reproduce the anatomic ulnar footprint of the UCL. The purpose of this study was to describe a novel UCL reconstruction technique that utilizes proximal-to-distal ulnar bone tunnels to better re-create the anatomy of the UCL and to compare the biomechanical profile at time zero among this technique, the native UCL, and the traditional docking technique. HYPOTHESIS: The biomechanical profile of the anatomic technique is similar to the native UCL and traditional docking technique. STUDY DESIGN: Controlled laboratory study. METHODS: Ten matched cadaveric elbows were potted with the forearm in neutral rotation. The palmaris longus tendon graft was harvested, and bones were sectioned 14 cm proximal and distal to the elbow joint. Specimen testing included (1) native UCL testing performed at 90° of flexion with 0.5 N·m of valgus moment preload, (2) cyclic loading from 0.5 to 5 N·m of valgus moment for 1000 cycles at 1 Hz, and (3) load to failure at 0.2 mm/s. Elbows then underwent UCL reconstruction with 1 elbow of each pair receiving the classic docking technique using either anatomic (proximal to distal) or traditional (anterior to posterior) tunnel locations. Specimen testing was then repeated as described. RESULTS: There were no differences in maximum load at failure between the anatomic and traditional tunnel location techniques (mean ± SD, 34.90 ± 10.65 vs 37.28 ± 14.26 N·m; P = .644) or when including the native UCL (45.83 ± 17.03 N·m; P = .099). Additionally, there were no differences in valgus angle after 1000 cycles across the anatomic technique (4.58°± 1.47°), traditional technique (4.08°± 1.28°), and native UCL (4.07°± 1.99°). The anatomic group and the native UCL had similar valgus angles at failure (24.13°± 5.86° vs 20.13°± 5.70°; P = .083), while the traditional group had a higher valgus angle at failure when compared with the native UCL (24.88°± 6.18° vs 19.44°± 5.86°; P = .015). CONCLUSION: In this cadaveric model, UCL reconstruction with the docking technique utilizing proximal-to-distal ulnar tunnels better restored the ulnar footprint while providing valgus stability comparable with reconstruction with the docking technique using traditional anterior-to-posterior ulnar tunnel locations. These results suggest that utilization of the anatomic tunnel location in UCL reconstruction has similar biomechanical properties to the traditional method at the time of initial fixation (ie, not accounting for healing after reconstruction in vivo) while keeping the ulnar tunnels farther from the ulnar nerve. Further studies are warranted to determine if an anatomically based UCL reconstruction results in differing outcomes than traditional reconstruction techniques. CLINICAL RELEVANCE: Current UCL reconstruction techniques do not accurately re-create the ulnar UCL footprint. The UCL is a dynamic constraint to valgus loads at the elbow, and a more anatomic reconstruction may afford more natural joint kinematics. This more anatomic technique performs similarly to the traditional docking technique at time zero, and the results of this study may offer a starting point for future in vivo studies.

Risk Factors for Distal Radius Osteotomy Nonunion.

BACKGROUND: Osteotomy-site nonunion after distal radius corrective osteotomy is a detrimental complication. This retrospective study aims to identify patient and surgical factors associated with nonunion risk to help mitigate this. The authors hypothesize that patient factors and potentially modifiable surgical factors are contributory. METHODS: Thirty-three patients who underwent corrective osteotomy of the distal radius for prior fracture malunion were identified. Radiographs and patient records were reviewed for demographics, comorbidities, nutritional status, plate position, angle and length of osteotomy correction, and graft used. The primary study outcome was osteotomy nonunion. Descriptive and bivariate statistics were used to identify covariates relevant to nonunion. Backward, stepwise logistic regression was applied to investigate the multivariate effects on outcome, and regression analysis was adjusted for confounders. RESULTS: Seven patients (21 percent) experienced nonunion after initial corrective osteotomy. Risk factors associated with nonunion included correction length of osteotomy of 5 mm or greater and prior treatment with open reduction and internal fixation. Autograft use was protective against nonunion. History of osteoporosis showed a trend toward increased risk. Angle of osteotomy correction, nutritional deficit, age, diabetes, smoking status, and obesity were not identified as risk factors by the multivariate model. CONCLUSIONS: Distraction length at the osteotomy site, graft selection, and prior internal fixation were significant risk factors for distal radius osteotomy nonunion, but other factors traditionally associated with nonunion did not appear to impact risk. The authors recommend using autograft bone augmentation, particularly when distracting the osteotomy beyond 5 mm or after prior internal fixation. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, III.

C-terminal domain small phosphatase 1 (CTDSP1) regulates growth factor expression and axonal regeneration in peripheral nerve tissue.

Peripheral Nerve Injury (PNI) represents a major clinical and economic burden. Despite the ability of peripheral neurons to regenerate their axons after an injury, patients are often left with motor and/or sensory disability and may develop chronic pain. Successful regeneration and target organ reinnervation require comprehensive transcriptional changes in both injured neurons and support cells located at the site of injury. The expression of most of the genes required for axon growth and guidance and for synapsis formation is repressed by a single master transcriptional regulator, the Repressor Element 1 Silencing Transcription factor (REST). Sustained increase of REST levels after injury inhibits axon regeneration and leads to chronic pain. As targeting of transcription factors is challenging, we tested whether modulation of REST activity could be achieved through knockdown of carboxy-terminal domain small phosphatase 1 (CTDSP1), the enzyme that stabilizes REST by preventing its targeting to the proteasome. To test whether knockdown of CTDSP1 promotes neurotrophic factor expression in both support cells located at the site of injury and in peripheral neurons, we transfected mesenchymal progenitor cells (MPCs), a type of support cells that are present at high concentrations at the site of injury, and dorsal root ganglion (DRG) neurons with REST or CTDSP1 specific siRNA. We quantified neurotrophic factor expression by RT-qPCR and Western blot, and brain-derived neurotrophic factor (BDNF) release in the cell culture medium by ELISA, and we measured neurite outgrowth of DRG neurons in culture. Our results show that CTDSP1 knockdown promotes neurotrophic factor expression in both DRG neurons and the support cells MPCs, and promotes DRG neuron regeneration. Therapeutics targeting CTDSP1 activity may, therefore, represent a novel epigenetic strategy to promote peripheral nerve regeneration after PNI by promoting the regenerative program repressed by injury-induced increased levels of REST in both neurons and support cells.

Dorsal Bridge Plate for Distal Radius Fractures: A Systematic Review.

PURPOSE: This study presents patient demographics, injury characteristics, outcomes, and complications associated with dorsal bridge plating (DBP) in the treatment of distal radius fractures. METHODS: A literature search performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines identified 206 articles, 12 of which met inclusion criteria, accounting for 310 patients. Included articles contained the results of DBP for treatment of distal radius fractures with reported outcomes between 1988 and 2018. Data were pooled and analyzed focusing on patient demographics, as well as 3 primary outcomes of complications, range of motion (ROM), and Disabilities of the Arm, Shoulder, and Hand (DASH) and QuickDASH scores. RESULTS: Average age was 55 years, median follow-up was 24 months, and the most common use was in comminuted (92%) intra-articular (92%) distal radius fracture caused by fall (58%), or motor vehicle collision or motorcycle collision (27%). A minority of patients had open fractures (16%) and most were cases of polytrauma (65%). Median time from placement to DBP removal was 17 weeks (mean, 119 days). At final follow-up, mean wrist ROM was 45° flexion, 50° extension, 75° pronation, and 73° supination. Mean DASH score was 26.1, and mean QuickDASH score was 19.8. The overall rate for any complication was 13%; the most common was hardware failure (3%) followed by symptomatic malunion or nonunion (3%), and persistent pain after hardware removal (2%). CONCLUSIONS: Dorsal bridge plating was found to be used most commonly in intra-articular, comminuted distal radius fractures with overall functional wrist ROM, moderate patient-reported disability, and a 13% complication rate at follow-up. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Surgical Elbow Dislocation Approach to the Distal Humerus for Apparent Capitellar and Lateral Condyle Fractures in Adults.

OBJECTIVES: Access to fractures of the distal humeral capitellum, trochlea, and lateral condyle is difficult through traditional approaches due to limited anterior articular exposure for direct reduction and fixation. The purpose of this study is to evaluate the relative articular exposure of a surgical dislocation (SD) approach to the distal humerus compared with olecranon osteotomy (OO). METHODS: Eight paired elbows from 4 cadavers underwent either SD or OO approach. Methylene blue staining demarcated visualized articular surface before disarticulation of the elbows. The main outcome measures were average visualized total distal humeral articular surface and anterior and posterior surface, and capitellar surface relative to the total surfaces was compared for each surgical approach using unpaired parametric t-tests. RESULTS: Intraclass correlation between raters was 0.995. The median exposed articular surface for SD and OO approaches was 90.0% and 62.8%, respectively. The overall exposure was significantly greater for the dislocation technique (P = 0.0003). With respect to specific regions of the distal humeral articular surface, SD allowed significantly greater visualization of the anterior surface (95.9% vs. 48.9%, P < 0.0001) and capitellum (100% vs. 40.4%, P < 0.0001). CONCLUSION: The surgical elbow dislocation approach to the distal humerus permits near total exposure of the anterior articular surface and the entire capitellum. Our data support this approach for anterior articular fractures of the distal humerus, to include those fractures that extend to the medial surface of the trochlea.

Femoral Neck Hounsfield Units as an Adjunct for Bone Mineral Density After Combat-Related Lower Extremity Amputation.

OBJECTIVES: To correlate femoral neck Hounsfield units (HUs) measured on a computed tomography (CT) scan to dual-energy x-ray absorptiometry (DEXA) T-scores allowing evaluation of bone mineral density (BMD) over time after lower extremity trauma-related amputation. DESIGN: Retrospective cohort study. SETTING: United States military trauma referral center. PATIENTS: Military combat-related lower extremity amputees with both DEXA and CT scans within 6 months of each other. INTERVENTION: None. MAIN OUTCOME MEASURES: Correlation between femoral neck comprehensive mean HUs and BMD and HUs threshold for low BMD. RESULTS: Regression model correlation (r) between CT HU and DEXA T-score was r = 0.84 [95% confidence interval (CI) 0.52-0.94] and r = 0.81 (95% CI 0.57-0.92) when CT imaging was separated from DEXA by less than 4 and 5 months, respectively. Beyond 5 months separation, correlation decreased to r = 0.60 (95% CI 0.29-0.80). Using a receiver operator characteristic curve for mean comprehensive HUs to determine low BMD with 4-month cut-off, a threshold of 151 HUs was 97% sensitive and 84% specific to identify low BMD, whereas 98 HUs was 100% sensitive and 100% specific to identify osteoporosis. CONCLUSION: Using opportunistic CT, clinicians can reliably estimate BMD in trauma-related amputees. This information will inform providers making decisions regarding weightbearing and bisphosphonate therapy to limit further loss. Future phases of this study will aim to use this correlation to study the effects of weightbearing advancement timing, bisphosphonate therapy, and interventions on the natural history of bone density after amputation. LEVEL OF EVIDENCE: Diagnostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

SARS-CoV-2 and limb ischemia: A systematic review.

BACKGROUND: Recent spread of severe acute respiratory coronavirus syndrome-2 (SARS-CoV-2) has led to the coronavirus disease (COVID-19) pandemic, resulting in new challenges across all medical specialties. Limb and digit ischemia have been associated with COVID-19 infection. This systematic review includes primary studies of COVID-19 limb ischemia to identify risk factors, comorbidities, case characteristics, and treatment strategies to better understand the nature of this disease and its effects on the extremities. METHODS: A literature search for studies detailing COVID-19 infected patients with limb or digit ischemia was performed, identifying 157 articles, 12 of which met inclusion criteria, accounting for 47 patients. Inclusion criteria were (1) primary studies, (2) positive disease diagnosis (3) limb ischemia, (4) reported treatment. Demographic data, case characteristics, treatments, outcomes and mortality were collected and pooled. RESULTS: The average patient age was 67.6 years, predominantly male (79.6%). Of the 44 cases discussing treatment, 13 (30%) patients underwent medical treatment alone, while 23 (52.3%) patients underwent medical plus surgical treatment. Four patients (9.1%) were treated with observation. In 10 of the 12 studies, lab findings, thrombosis, or conclusions supporting a hypercoagulable state as a cause of limb/digit ischemia were cited. Five patients (10.6%) were on vasopressors and 8 patients (17.0%) were on a ventilator. Of those treated with observation alone, there was 100% resolution of symptoms. Of those treated medically without surgical intervention (17 patients), 6 patients (35.3%) were reported to have revascularization, 6 patients (35.3%) died, and the remaining outcomes were not reported. Medical and surgical treatment resulted in one limb amputation (4.4%) and altogether 74% of patients achieved revascularization of the affected limb/digit. Mortality rate was 45%. CONCLUSIONS: COVID-19 infection may be associated with increased risk of limb or digital ischemia, although the quality of evidence supporting this theory is limited. Evidence of inflammatory-mediated thrombosis and endothelial injury are possible explanations which would support the use of immunotherapy in addition to anticoagulation for treatment or prevention of thromboembolic events. Current outcomes and treatment strategies are variable. LEVEL OF EVIDENCE: IV.

Management of Postoperative Facet Cysts: A Report of 3 Cases.

CASE: The exact underlying etiology behind synovial facet cysts remains unclear, and optimal surgical management continues to be a challenge. The authors present a series of 3 patients who underwent primary lumbar decompression and developed postoperative facet cysts within 6 months of index surgery requiring operative intervention. No patients had radiographic evidence of instability. Average follow-up after revision surgery was 14 months. CONCLUSION: We report on the 3 cases with the phenomenon of postoperative facet cysts and present a complication that falls within the spectrum of lumbar decompression surgery with several successful treatment options.

A Case Report of Rapid Aseptic Intervertebral Disc Destruction After Lumbar Microdiscectomy: A Case Report.

CASE: A previously healthy military recruit underwent routine microdiscectomy after lumbar disc herniation. After a period of improvement, he developed recurrent pain without repeat injury. Advanced imaging showing loss of marrow signal, and disc height was concerning for discitis. Inflammatory markers remained negative. Conservative treatment without antibiotics led to symptom resolution. CONCLUSION: This case demonstrates an unusual complication after lumbar microdiscectomy in a healthy individual. The recurrent symptoms and imaging changes were likely secondary to aseptic discitis and rapid degeneration rather than infection. A stepwise approach is critical for determining the cause of pain exacerbation after spinal procedures.

The impact of pre-existing ulnar nerve instability on the surgical treatment of cubital tunnel syndrome: a systematic review.

BACKGROUND: The decision to perform nerve transposition (NT) or in situ decompression (SD) during surgical treatment of cubital tunnel syndrome is often based on nerve subluxation through elbow motion. This review assesses what impact nerve instability has on study design and reported outcomes. METHODS: A search was performed with Boolean operators: "ulnar nerve" OR "cubital tunnel" AND "decompression" OR "transposition" on PubMed, Clinical Key, and CINAHL to identify primary studies comparing NT and SD that report pre-existing nerve instability. Primary outcome was the effect of instability on study design. Secondary outcomes were nerve instability, patient-reported scores, and complications. RESULTS: Five studies met criteria after screening 134 articles. In 3 studies, nerve instability dictated treatment. Prospective randomization was maintained in 1 study. Included cases totaled 464 SD and 304 NT. The complication rate was 8.6% overall, 4.3% for SD and 21.1% for NT. Bishop scores were 56.9% excellent and 37.3% good for stable nerves and 62.0% excellent and 29.3% good for unstable nerves. CONCLUSIONS: Very few studies report ulnar nerve instability, and study design is biased by ulnar nerve subluxation. Outcomes showed similar symptomatic improvement for both decompressed and transposed groups with higher complication rates for the transposed group.

Validation of PATHFx 2.0: An open-source tool for estimating survival in patients undergoing pathologic fracture fixation.

Treatment decisions in patients with metastatic bone disease rely on accurate survival estimation. We developed the original PATHFx models using expensive, proprietary software and now seek to provide a more cost-effective solution. Using open-source machine learning software to create PATHFx version 2.0, we asked whether PATHFx 2.0 could be created using open-source methods and externally validated in two unique patient populations. The training set of a well-characterized, database records of 189 patients and the bnlearn package within R Version 3.5.1 (R Foundation for Statistical Computing), was used to establish a series of Bayesian belief network models designed to predict survival at 1, 3, 6, 12, 18, and 24 months. Each was externally validated in both a Scandinavian (n = 815 patients) and a Japanese (n = 261 patients) data set. Brier scores and receiver operating characteristic curves to assessed discriminatory ability. Decision curve analysis (DCA) evaluated whether models should be used clinically. DCA showed that the model should be used clinically at all time points in the Scandinavian data set. For the 1-month time point, DCA of the Japanese data set suggested to expect better outcomes assuming all patients will survive greater than 1 month. Brier scores for each curve demonstrate that the models are accurate at each time point. Statement of Clinical Significance: we successfully transitioned to PATHFx 2.0 using open-source software and externally validated it in two unique patient populations, which can be used as a cost-effective option to guide surgical decisions in patients with metastatic bone disease.