Sanchez-Sotelo, Joaquin

Aims Arthrofibrosis is a relatively common complication after joint injuries and surgery, particularly in the knee. The present study used a previously described and validated rabbit model to assess the biomechanical, histopathological, and molecular effects of the mast cell stabilizer ketotifen on surgically induced knee joint contractures in female rabbits. Methods A group of 12 skeletally mature rabbits were randomly divided into two groups. One group received subcutaneous (SQ) saline, and a second group received SQ ketotifen injections. Biomechanical data were collected at eight, ten, 16, and 24 weeks. At the time of necropsy, posterior capsule tissue was collected for histopathological and gene expression analyses (messenger RNA (mRNA) and protein). Results At the 24-week timepoint, there was a statistically significant increase in passive extension among rabbits treated with ketotifen compared to those treated with saline (p = 0.03). However, no difference in capsular stiffness was detected. Histopathological data failed to demonstrate a decrease in the density of fibrous tissue or a decrease in α-smooth muscle actin (α-SMA) staining with ketotifen treatment. In contrast, tryptase and α-SMA protein expression in the ketotifen group were decreased when compared to saline controls (p = 0.007 and p = 0.01, respectively). Furthermore, there was a significant decrease in α-SMA (ACTA2) gene expression in the ketotifen group compared to the control group (p < 0.001). Conclusion Collectively, these data suggest that ketotifen mitigates the severity of contracture formation in a rabbit model of arthrofibrosis. Cite this article: Bone Joint Res 2020;9(6):302–310.

AbstractPurposeTo compare rates of recurrent instability, revision surgery and functional outcomes following arthroscopic anterior capsulolabral repair for recurrent anterior instability using knot‐tying versus knotless suture anchor techniques.MethodsPatients who had undergone arthroscopic anterior labrum and capsular repair for recurrent anterior glenohumeral instability using knotless anchors were identified. Those with minimum 2‐year follow‐up were matched (1:2) to knot‐tying anchor repair patients. Rates of failure and recurrent instability were compared, as well as Visual Analog Scale (VAS), Single Assessment Numeric Evaluation (SANE), Quick Disabilities of the Arm, Shoulder and Hand (QuickDASH), University of California Los Angeles (UCLA) and Rowe scores.ResultsOne hundred and two patients (89 males, 13 females) with a mean age of 24.3 ± 9.6 were included. Repair was performed with knotless anchors in 34 and knot‐tying anchors in 68 shoulders. At mean follow‐up of 4.8 ± 2.5 years, re‐dislocation rates between groups were not significantly different (knotless anchor: 9% versus knot‐tying group: 15%, n.s.), but the knot‐tying group showed a higher re‐subluxation rate (p = 0.039). 12 (18%) revisions were performed in the knot‐tying group at a mean 2.9 years after surgery and 1 (3%) revision in the knotless anchors group at 1.4 years (n.s.). There was no difference in mean VAS with use (1.3 ± 1.9 versus 0.8 ± 1.5, n.s.), SANE scores (91.8 ± 12.7 versus 92.0 ± 11.0, n.s.), QuickDASH scores (4.1 ± 5.5 versus 3.0 ± 6.5, n.s.), UCLA Shoulder Score (32.5 ± 3.6 versus 33.2 ± 3.1, n.s.), or Rowe scores (90.5 ± 18.5 versus 92.2 ± 16.6, n.s.) between knotless and knot‐tying groups, respectively. VAS at rest was higher in the knotless group (0.7 ± 1.5 vs 0.1 ± 0.4, p = 0.021).ConclusionsKnotless anchors demonstrated similar rates of re‐dislocation and revision surgery, and lower rates of recurrent subluxation, compared to knot‐tying anchors. Patients achieved good‐to‐excellent functional outcomes. This supports the efficacy of knotless anchors as an alternative to knot‐tying anchors for arthroscopic anterior labral repair of recurrent anterior shoulder dislocation.Level of evidenceIII.

Abstract Despite recent improvements in surgical implants and techniques, distal humerus nonunion does occur between 8% and 25% of the time. Careful identification and improvement of any modifiable risk factors such as smoking, metabolic disorders, immunosuppressant medications, poor nutritional status and infection is mandatory. A recent computed tomography scan is paramount to determine the nonunion pattern, assess residual bone stock, identify previously placed hardware, and determine whether there is evidence of osteoarthritis or malunion of the articular surface. Internal fixation is the treatment of choice in the majority of patients presenting with reasonable bone stock and preserved articular cartilage; total elbow arthroplasty is an appealing alternative for elbows with severe destruction of the articular cartilage or severe bone loss at the articular segment, especially in older, female patients. Internal fixation requires not only achieving a stable fixation, but also releasing associated elbow contractures and the liberal use of bone graft or substitutes. Although reported union rates after internal fixation of distal humerus nonunions are excellent (over 95%), the complication rate remains very high, and unsatisfactory results do occur. Cite this article: EFORT Open Rev 2020;5:289-298. DOI: 10.1302/2058-5241.5.190050

AbstractThe dense formation of abnormal scar tissue after total knee arthroplasty results in arthrofibrosis, an unfortunate sequela of inflammation. The purpose of this study was to use a validated rabbit model to assess the effects on surgically‐induced knee joint contractures of two combined pharmacological interventions: celecoxib (CXB) loaded on an implanted collagen membrane, and subcutaneously (SQ) injected ketotifen. Thirty rabbits were randomly divided into five groups. The first group received no intervention after the index surgery. The remaining four groups underwent intra‐articular implantation of collagen membranes loaded with or without CXB at the time of the index surgery; two of which were also treated with SQ ketotifen. Biomechanical joint contracture data were collected at 8, 10, 16, and 24 weeks. At the time of necropsy (24 weeks), posterior capsule tissue was collected for messenger RNA and histopathologic analyses. At 24 weeks, there was a statistically significant increase in passive extension among rabbits in all groups treated with CXB and/or ketotifen compared to those in the contracture control group. There was a statistically significant decrease in COL3A1, COL6A1, and ACTA2 gene expression in the treatment groups compared to the contracture control group (P < .001). Histopathologic data also demonstrated a trend towards decreased fibrous tissue density in the CXB membrane group compared to the vehicle membrane group. The present data suggest that intra‐articular placement of a treated collagen membrane blunts the severity of contracture development in a rabbit model of arthrofibrosis, and that ketotifen and CXB may independently contribute to the prevention of arthrofibrosis. Statement of clinical significance: Current literature has demonstrated that arthrofibrosis may affect up to 5% of primary total knee arthroplasty patients. For that reason, novel pharmacologic prophylaxis and treatment modalities are critical to mitigating reoperations and revisions while improving the quality of life for patients with this debilitating condition.

Aims Reverse shoulder arthroplasty (RSA) reliably improves shoulder pain and function for a variety of indications. However, the safety and efficacy of RSA in elderly patients is largely unknown. The purpose of this study was to report the mortality, morbidity, complications, reoperations, and outcomes of primary RSA in patients aged > 80 years. Patients and Methods Between 2004 and 2013, 242 consecutive primary RSAs were performed in patients aged > 80 years (mean 83.3 years (sd 3.1)). Of these, 53 were lost to follow-up before two years and ten had died within two years of surgery, leaving 179 for analysis of survivorship, pain, motion, and strength at a minimum of two years or until revision surgery. All 242 patients were considered for the analysis of 90-day, one-year, and overall mortality, medical complications (90-day and overall), surgical complications, and reoperations. The indications for surgery included rotator cuff arthropathy, osteoarthritis, fracture, the sequela of trauma, avascular necrosis, and rheumatoid arthritis. A retrospective review of the medical records was performed to collect all variables. Survivorship free of revision surgery was calculated at two and five years. Results One patient (0.4%) died within the first 90 days. A total of 45 patients (19%) were known to have died at the time of the final follow-up, with a median time to death of 67.7 months (interquartile range 40.4 to 94.7) postoperatively. Medical complications occurred in six patients (3%) and surgical complications occurred in 21/179 patients (12%). Survivorship free from revision was 98.9% at two years and 98.3% at five years; survivorship free from loosening was 99.5% at final follow-up. The presence of peripheral vascular disease correlated with a higher complication rate. Conclusion Primary RSA was safe and effective in patients aged > 80 years, with a relatively low rate of medical and surgical complications. Thus, age alone should not be a contraindication to primary RSA in patients aged > 80 years. However, a careful evaluation of comorbidities is required in this age group when considering primary RSA. Cite this article: Bone Joint J 2019;101-B:1520–1525

Background: While a large volume of literature has focused on risk factors for anterior shoulder instability, the rates of recurrence are inconsistent and require additional population-based epidemiologic data. Purpose/Hypothesis: The purpose was to report the effect of patient age on the number of instability events before physician consultation, rate of surgical stabilization, recurrent instability, and progression to osteoarthritis in patients <40 years old with anterior shoulder instability, utilizing an established US geographic population. We hypothesized that younger patients would be more likely to experience multiple episodes of instability before evaluation, undergo surgery, and experience recurrent instability after surgical intervention. Study Design: Descriptive epidemiologic study. Methods: An established geographic database of more than 500,000 patients was used to identify patients <40 years of age with anterior shoulder instability between 1994 and 2016. Medical records were reviewed to obtain patient characteristics, history, imaging, surgical details, and outcomes. Patients were divided into 5 groups based on age (≤15, 16-20, 21-25, 26-30, and 31-40 years) at initial instability. Comparative analysis was performed to identify differences between groups. Results: The study population consisted of 654 patients with a mean follow-up of 11.1 years (range, 2.0-25.2 years). This resulted in 118 patients (18%) ≤15 years of age at initial instability; 250 (38%), 16 to 20 years; 110 (17%), 21 to 25 years; 80 (12%), 26 to 30 years; and 96 (15%), 31 to 40 years. Of patients ≤15 years old at initial instability 47% had 3+ instability events, compared with 12% of patients aged 31 to 40 years ( P < .001). At 10 years of follow-up, patients ≤15 and 16 to 20 years old demonstrated the highest recurrent instability rates of 38.8% and 47.1% after nonoperative management, respectively. Patients 16 to 20 years old demonstrated the highest rates of both surgical intervention (40.4%) and recurrence after surgery (24.8%). Patients 31 to 40 years of age were significantly more likely to develop clinically symptomatic osteoarthritis (15.6%) than all other age groups. Conclusion: In a US epidemiologic population of patients <40 years old, the rate of recurrent anterior shoulder instability was roughly one-third after initial physician consultation. Younger patients, particularly those ≤15 and 16 to 20 years of age, were more likely to have experienced multiple instability events at the time of initial evaluation, require surgery, and experience recurrent instability compared with older patients. For every year of decrease in age at initial instability, the risk of recurrent instability or surgical intervention after physician consultation increased by 4.1% and 2.8%, respectively.

ABSTRACTArthrofibrosis is a common complication following total knee arthroplasty caused by pathologic fibroblast activation and excessive collagen deposition around a synovial joint leading to debilitating loss of motion. Treatment options are limited because the pathologic mechanisms remain to be characterized. Dysregulation of the inflammatory cascade may lead to communication between myofibroblasts and immune cells triggering tissue metaplasia, and excessive collagen deposition described clinically as arthrofibrosis. We explored the novel use of celecoxib (selective cyclooxygenase‐2 [COX‐2] inhibitor) to disrupt the downstream effects of the post‐traumatic inflammatory cascade and inhibit scar tissue formation in a validated rabbit model of arthrofibrosis combined with new parameters for quantifying the stiffness of the posterior capsule. Biomechanical and molecular analyses, of contracted rabbit knee posterior capsule tissue after COX‐2 inhibition revealed increased maximal passive extension and down‐regulation of collagen messenger RNA compared with controls. Histopathologic examination suggested a trend of decreased quantities of dense fibrous connective tissue with COX‐2 inhibition. These data may suggest that inhibiting the inflammatory cascade could potentially reduce pathologic myofibroblast activation, thereby reducing scar tissue formation and increasing the range of motion in arthrofibrotic joints. Implementing a multi‐modal pharmacologic approach may simultaneously target numerous cellular components contributing to the complex process of arthrofibrogenesis. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:2609–2620, 2019

Abstract Although anterior shoulder instability is most commonly treated with arthroscopic fixation, open labral repair with capsular shift may be best for select patients and in cases of revision stabilization without significant bone loss. The technique described in this article uses the deltopectoral interval; it involves careful dissection of the subscapularis from the anterior capsule, repair of the Bankart lesion, and a lateral and superior capsular shift using all‐suture anchors in the humeral head. Advantages of this technique include meticulous control of anchor placement and the ability to provide additional stability via a lateral and superiorly directed capsular shift. This operation can be performed in a reliable, efficient, and reproducible manner. Technique Video video See video under supplementary data.

ABSTRACT Musculoskeletal infections (MSKI) remain the bane of orthopedic surgery, and result in grievous illness and inordinate costs that threaten healthcare systems. As prevention, diagnosis, and treatment has remained largely unchanged over the last 50 years, a 2nd International Consensus Meeting on Musculoskeletal Infection (ICM 2018, https://icmphilly.com ) was completed. Questions pertaining to all areas of MSKI were extensively researched to prepare recommendations, which were discussed and voted on by the delegates using the Delphi methodology. The questions, including the General Assembly (GA) results, have been published ( GA questions ). However, as critical outcomes include: (i) incidence and cost data that substantiate the problems, and (ii) establishment of research priorities; an ICM 2018 research workgroup (RW) was assembled to accomplish these tasks. Here, we present the result of the RW consensus on the current and projected incidence of infection, and the costs per patient, for all orthopedic subspecialties, which range from 0.1% to 30%, and $17,000 to $150,000. The RW also identified the most important research questions. The Delphi methodology was utilized to initially derive four objective criteria to define a subset of the 164 GA questions that are high priority for future research. Thirty‐eight questions (23% of all GA questions) achieved the requisite > 70% agreement vote, and are highlighted in this Consensus article within six thematic categories: acute versus chronic infection, host immunity, antibiotics, diagnosis, research caveats, and modifiable factors. Finally, the RW emphasizes that without appropriate funding to address these high priority research questions, a 3rd ICM on MSKI to address similar issues at greater cost is inevitable.

Background Preoperative planning software has been developed to measure glenoid version, glenoid inclination, and humeral head subluxation on computed tomography (CT) for shoulder arthroplasty. However, most studies analyzing the effect of glenoid positioning on outcome were done prior to the introduction of planning software. Thus, measurements obtained from the software can only be extrapolated to predict failure provided they are similar to classic measurements. The purpose of this study was to compare measurements obtained using classic manual measuring techniques and measurements generated from automated image analysis software. Methods Ninety-five two-dimensional computed tomography scans of shoulders with primary glenohumeral osteoarthritis were measured for version according to Friedman method, inclination according to Maurer method, and subluxation according to Walch method. DICOM files were loaded into an image analysis software (Blueprint, Wright Medical) and the output was compared with values obtained manually using a paired sample t-test. Results Average manual measurements included 13.8° version, 13.2° inclination, and 56.2% subluxation. Average image analysis software values included 17.4° version (3.5° difference, p < 0.0001), 9.2° inclination (3.9° difference, p < 0.001), and 74.2% for subluxation (18% difference, p < 0.0001). Conclusions Glenoid version and inclination values from the software and manual measurement on two-dimensional computed tomography were relatively similar, within approximately 4°. However, subluxation measurements differed by approximately 20%.