Alder, Kareme D.

Case: A right-hand dominant, 38-year-old man presented to clinic with atraumatic left wrist pain of 1 year duration in the setting of bilateral bipartite lunate. Both wrists ultimately became symptomatic and were treated with proximal row carpectomy. The patient had durable pain relief in both wrists after proximal row carpectomy. Conclusion: Bipartite lunate is a rare developmental anomaly that is usually asymptomatic. Operative intervention directed at treating involved osteoarthritic joints is warranted in the rare symptomatic patient. Clinicians should be aware of the pathology given its high rate of misdiagnosis.

Arthrofibrosis is a common complication following total knee arthroplasty and is the result of a dysregulated immuno-inflammatory cascade, which culminates in excessive scar deposition by myofibroblasts within the knee joint. Pharmacotherapies for arthrofibrosis are limited, with treatment reliant on manipulation under anesthesia or lysis of adhesions with or without component revision. Bupivacaine (a local anesthetic) and meloxicam (a nonsteroidal anti-inflammatory drug) combination therapy may exert antifibrotic properties by limiting inflammatory cell recruitment and the subsequent release of profibrotic cytokines. The purpose of this study was to evaluate the effects of this combination therapy in a rabbit model of arthrofibrosis by evaluating live and postsacrifice knee biomechanics and gene expression of posterior knee capsule tissue. Forty New Zealand white rabbits were equally divided into two experimental groups and prospectively studied to assess knee passive extension angles (PEA), terminal posterior capsular stiffness, and the inflammatory milieu of the posterior knee joint capsule. Experimental limbs with and without combination therapy showed similar live PEAs and terminal posterior capsular stiffness, with no significant differences between the groups. Gene expression analysis, however, revealed significant reduction in inflammatory genes but not profibrotic genes. In summary, bupivacaine and meloxicam combination therapy did not exert antifibrotic effects in a rabbit model of arthrofibrosis but significantly reduced the expression of inflammatory markers in the local environment of the posterior capsule.

Background: Outcomes after arthroscopic rotator cuff repair (RCR) are frequently measured through clinically significant outcomes (CSOs) such as the minimal clinically important difference, the substantial clinical benefit, and the Patient Acceptable Symptom State. Global achievement of CSOs is challenging to predict. Purpose: To determine if unsupervised machine learning can identify distinct patient subgroups based on CSO achievement after elective arthroscopic RCR. Study Design: Case-control study; Level of evidence, 3. Methods: A prospectively collected database was analyzed to identify patients who underwent elective arthroscopic RCR from 2015 to 2017. Tear dimensions were measured on magnetic resonance imaging utilizing a validated technique. CSO achievements on the American Shoulder and Elbow Surgeons, the Single Assessment Numeric Evaluation, and the Constant-Murley subjective score at 2-year follow-up were calculated. An unsupervised random forest algorithm was utilized to develop and internally validate patient subgroups with significantly different rates of CSO achievement. Patient subgroup membership, along with a total of 30 demographic and clinical variables, as well as preoperative patient-reported outcomes, were incorporated into a stepwise multivariable logistic regression to identify factors predictive of optimal CSO achievement. Results: A total of 346 patients (192 male; mean ± SD age, 57.2 ± 9.1 years; body mass index, 30.1 ± 5.4 kg/m 2 ) were eligible for inclusion and followed for a mean of 3.8 years (range, 2.0-6.2 years) Of these, a total of 333 patients were partitioned by the random forest algorithm into 2 subgroups (stability, 0.16; connectivity: 180.8; Dunn: 0.16; silhouette: 0.05), with 176 patients in the optimal achievement subgroup and 157 patients in the suboptimal achievement subgroup. The 2 subgroups differed significantly (all P ≤ .004) in the likelihood of achievement of all CSOs. Stepwise multivariable logistic regression identified an increase of 1 mm in tear size in the sagittal dimension beyond 1.9 cm to predict a 10% increase in the probability of suboptimal achievement. Additional risk factors for suboptimal CSO achievement included increasing number of tendons involved (odds ratio [OR], 14.07; 95% CI, 4.50-44.02; P < .001), subscapularis involvement (OR, 8.67; 95% CI, 2.45-30.71; P = .01), and increased preoperative CMS score (OR, 1.11; 95% CI, 1.04-1.18; P = .001). Protective factors included performance of a subpectoral biceps tenodesis compared with biceps tenotomy (OR, 0.22; 95% CI, 0.05-0.92; P = .03). Conclusion: Clinically meaningful subgroups were uncovered using an unsupervised machine learning algorithm in patients undergoing arthroscopic RCR. Tear size, number of tendons involved, and subscapularis involvement were significant and additive predictors of suboptimal CSO achievement at 2-year minimum follow-up. Treatment of concurrent biceps pathology with tenodesis conferred 78% increased likelihood of CSO achievement compared with tenotomy.

Experimental analyses of knee joint contractures have traditionally utilized a 6-month rabbit model as the gold standard. However, this model is time-intensive and costly. The purpose of this study was to develop an abbreviated rabbit model of knee contractures and compare it to the well-established longer model. Twenty female New Zealand White rabbits were divided into two equal groups and prospectively studied to assess knee passive extension angles (PEA), contracture angles (CA), and terminal posterior capsular stiffness. Experimental knees were immobilized for either 4 weeks ( n = 10) with an 8-week remobilization period in the abbreviated model (i.e., 3 months) or for 8 weeks ( n = 10) with a 16-week remobilization period in the standard model (i.e., 6 months). PEAs were assessed at remobilization and several time points using differing vertical forces. At sacrifice, terminal biomechanical data were collected to assess posterior capsular stiffness. Analysis of PEAs in live animals at each torque value and time point demonstrated increased PEAs and decreased CAs in the 3-month abbreviated model as compared to the 6-month standard model. At sacrifice, biomechanical analysis demonstrated that the posterior capsules of the 3-month experimental limbs were significantly more stiff than the contralateral limb (2.4 vs. 0.05 Ncm/°, p < 0.0001), but significantly less stiff compared to the 6-month experimental limbs (2.4 vs. 4.7 Ncm/°, p < 0.0001). Our study suggests that the 6-month standard rabbit knee model of arthrofibrosis should continue to be used in the laboratory assessment of arthrofibrosis. However, the abbreviated model may be beneficial under selected experimental conditions.

Background: Arthroscopic diagnosis and treatment of femoroacetabular pathology has experienced significant growth in the last 30 years; nevertheless, reduced utilization of orthopaedic procedures has been observed among the underrepresented population. Purpose/Hypothesis: The purpose of this study was to examine racial differences in case incidence rates, outcomes, and complications in patients undergoing hip arthroscopy. It was hypothesized that racial and ethnic minority patients would undergo hip arthroscopy at a decreased rate compared with their White counterparts but that there would be no differences in clinical outcomes. Study Design: Cross-sectional study. Methods: The State Ambulatory Surgery and Services Database and the State Emergency Department Database of New York were queried for patients undergoing hip arthroscopy between 2011 and 2017. Patients were stratified into White and racial and ethnic minority races, and intergroup comparisons were performed for utilization over time, total charges billed per encounter, 90-day emergency department (ED) visits, and revision hip arthroscopy. Temporal trends in the utilization of hip arthroscopy were identified, and racial differences in secondary outcomes were analyzed with a semiparametric method known as targeted maximum likelihood estimation (TMLE) backed by a library of machine learning algorithms. Results: A total of 9745 patients underwent hip arthroscopy during the study period, with 1081 patients of minority race (11.1%). White patients underwent hip arthroscopy at 5.68 (95% CI, 4.98-6.48) times the incidence rate of racial and ethnic minority patients; these incidence rates grew annually at a ratio of 1.11 in White patients compared with 1.03 in racial and ethnic minority patients ( P < .001). Based on the TMLE, racial and ethnic minority patients were significantly more likely to incur higher costs ( P < .001) and visit the ED within 90 days ( P = .049) but had negligible differences in reoperation rates at a 2-year follow-up ( P = .53). Subgroup analysis identified that higher likelihood for 90-day ED admissions among racial and ethnic minority patients compared with White patients was associated with Medicare insurance ( P = .002), median income in the lowest quartile ( P = .012), and residence in low-income neighborhoods ( P = .006). Conclusion: Irrespective of insurance status, racial and ethnic minority patients undergo hip arthroscopy at a lower incidence and incur higher costs per surgical encounter.

ABSTRACT Purpose: To determine and evaluate the distal forearm and wrist's cutaneous blood supply and vascular territories. Methods: Four cadaveric upper extremities were injected with a radiopaque, lead-based contrast agent through the brachial artery. After the lead-based contrast agent set, the cadaveric limbs underwent computed tomographic (CT) scanning to assess the perforators to the cutaneous skin of the distal forearm and wrist. High-resolution axial CT and three-dimensional reconstructions were generated to highlight perforating vessels stemming from their parent arteries. Subsequently, anatomic microdissections were performed to identify and trace the perforating vessels identified on CT. Results: CT analysis and anatomic microdissection demonstrated that the dorsal surface of the distal forearm and wrist are supplied by numerous perforators stemming predominantly from the anterior interosseous artery with some anastomotic contribution from the posterior interosseous, radial, and ulnar arteries. Perforators from the radial and ulnar arteries supply the volar surface. There are large anastomotic networks formed between the perforating vessels. Conclusions: The distal forearm and wrist have a robust anastomotic blood supply that has contributions from the anterior interosseous, posterior interosseous, radial, and ulnar arteries. Clinical relevance: The extensive perforator-derived blood supply to the skin likely accounts for the excellent soft tissue healing potential of the wrist following surgery utilizing multiple incisions. Highlights Distal radius fractures may require multiple incisions for anatomic reduction and fixation.Multiple incisions about the wrist are thought to predispose to wound complications and/or skin breakdown.The distal forearm and wrist have a robust anastomotic blood supply from the anterior interosseous, posterior interosseous, radial, and ulnar arteries.Multiple incisions do not necessarily predispose to wound complications given robust anastamosis.

Purpose To compare 3 separate blood flow restriction (BFR) systems in their capacity to reduce repetitions to failure, impact perceptual responses, and cause adverse events during a low‐load free‐flow exercise. Methods The study included healthy subjects aged 18 years or older who presented to an ambulatory‐care sports medicine clinic. On day 1, participants’ demographic characteristics and anthropomorphic measurements were recorded. Each participant performed dumbbell biceps curl repetitions to failure using 20% of his or her 1‐repetition maximum weight with each arm. Participants were exposed to 3 different tourniquet systems for familiarization. On day 2, each participant’s arm was randomized to a cuff system, and the participant performed 2 sets of biceps curl repetitions to failure with the cuff inflated. Repetitions to failure, rating of perceived effort (RPE), rating of perceived discomfort, and pulse oxygenation levels were recorded after each set. On day 3, participants completed a survey of their perceived delayed‐onset muscle soreness. Results The final analysis was performed on 42 arms, with 14 limbs per system. The study population had a mean age of 28.7 ± 2.4 years and a mean body mass index of 24.9 ± 4.3. All 3 systems successfully reduced repetitions to failure compared with unrestricted low‐load exercise from baseline to BFR set 1 and from baseline to BFR set 2. There were no significant between‐group differences among BFR systems regarding the number of repetitions to failure performed at baseline versus BFR set 1 or BFR set 2. The Delfi Personalized Tourniquet System (PTS) cohort had the greatest reductions in repetitions to failure from BFR set 1 to BFR set 2 ( P = .002) and reported the highest RPE after set 2 ( P = .025). Conclusions The Delfi PTS, SmartCuffs Pro, and BStrong BFR systems were each safe and were able to significantly reduce repetitions to failure compared with a low‐load free‐flow condition when used in a BFR exercise protocol. The Delfi PTS system may produce a higher RPE with prolonged use in comparison to the other systems. Level of Evidence Level II, prospective cohort study.

» The scaphotrapeziotrapezoid (STT) joint is a common location of degenerative osteoarthritis (OA) in the wrist. » STT OA may occur in isolation or with concomitant thumb carpometacarpal joint (CMCJ) OA or scapholunate advanced collapse (SLAC) and other wrist OA patterns. » Nonoperative management strategies include activity modification, bracing, anti-inflammatory medications, occupational therapy, and injections. » Surgical treatment may be determined by whether the STT OA occurs in isolation or with concomitant thumb CMCJ or SLAC OA and includes STT arthrodesis, distal scaphoid excision with or without interposition or implant arthroplasty, trapeziectomy with proximal trapezoid excision, four-corner fusion in combination with scaphoid/radial column excision, and proximal row carpectomy.

Objectives: Background: Arthroscopic diagnosis and treatment of femoroacetabular pathology has been increasingly used in the past thirty years with interventions resulting in improved hip function and ultimate delay of hip arthroplasty in a minimally invasive manner. Unfortunately, previous investigations have observed decreased rates of access, utilization of, and outcomes following orthopedic interventions such as hip arthroplasty in underrepresented patients. The purpose of this study is to examine racial differences in procedural rates, outcomes, and complications in patients undergoing hip arthroscopy. Methods: The State Ambulatory Surgery and Services Database (SASD) and State Emergency Department Database (SEDD) of New York were queried for patients undergoing hip arthroscopy from 2011 to 2017. The primary outcomes investigated were utilization over time, total charges billed per encounter, 90-day emergency department visits, and revision hip arthroscopy. Patients were stratified into White and non-White race, and intergroup differences were evaluated with descriptive statistics. Subgroup analysis was performed with linear mixed-effects models to identify significant interactions between race and individual variables that contributed to any differences in the outcomes of interest. Temporal trends in utilization of hip arthroscopy and concomitant procedures between the two groups were analyzed with Poisson regression modeling. Finally, targeted maximum likelihood estimation (TMLE) was performed to provide nonparametric estimates of the specific differences in the outcomes studied using machine learning ensembles while controlling for patient risk factors. Results: A total of 9,745 patients underwent hip arthroscopy during the study period, with 1,081 patients of non-White race (11.9%). Results of Poisson regression demonstrated an annual increase of 1.11 in the incidence rate of hip arthroscopy among White patients, compared to 1.03 for non-White patients (p<0.001), with this disparity projected to increase by 2040. Based on TMLE utilizing an ensemble of machine learning models, non-White patients were significantly more likely to incur higher costs (OR: 1.30, 95% CI: 1.24-1.37, p<0.001) and visit the emergency department within 90-days (OR: 1.09, 95% CI: 1.01, 1.18, p=0.05), but had negligible differences in reoperation rates at 90 days to 2 years (OR: 1.13, 95% CI: 0.78-1.63, p=0.53). Subgroup analysis identified higher likelihood for 90-day emergency department admissions among non-White patients compared to White patients, which were significantly compounded by Medicare insurance (OR: 2.95, 95% CI 1.46-5.95, p=0.002), median income in the lowest quartile (OR: 1.84, 95% CI: 1.2-2.61, p=0.012), and residence in low-income neighborhoods (OR: 2.05, 95% CI: 1.31-3.2, p=0.006). Subgroup analysis for charges billed and reoperation did not identify significant findings. Conclusions: Hip arthroscopy remains an increasingly utilized surgical technique for the treatment of a myriad of hip disorders. Unfortunately, racial disparities exist and are worsening over time. Irrespective of insurance status, non-white patients undergo hip arthroscopy at a lower rate, incur higher costs, and more frequently experience unexpected returns to the emergency department. Improved initiatives to improve the disparity in access to and outcomes following hip arthroscopy must be addressed to further its utility for all patients.

Abstract Despite the development of various therapeutic options, surgical management of irreparable rotator cuff tears (IRCTs) remains controversial. Recently, implantation of a biodegradable subacromial balloon spacer (InSpace, Stryker Corporation; Kalamazoo, MI) has gained considerable interest for the treatment of certain IRCTs. The reported outcome of balloon implantation has not been consistent, likely due to differing indications and technical approaches. The purpose of this article is to present a reproducible arthroscopic technique for implantation of a subacromial balloon and to review the literature published to date, regarding the efficacy and outcomes of this procedure. Technique Video video See video under supplementary data.