Remnant-Sparing Anterior Cruciate Ligament Reconstruction Results in Similar Clinical, Functional, and Quality-of-Life Outcomes to Anatomic Single-Bundle Anterior Cruciate Ligament Reconstruction.

Purpose: To compare a large cohort of patients who underwent remnant-sparing anterior cruciate ligament reconstruction (rACLR) with a matched group of patients who underwent anatomic single-bundle anterior cruciate ligament reconstruction (ACLR) with respect to clinical laxity, patient-reported outcomes, and functional testing. Methods: Patients who underwent rACLR between January 2010 and December 2015 were matched according to age, sex, body mass index, and graft type to patients who underwent ACLR. The primary outcome measure was the ACL Quality of Life (ACL-QOL) score at final follow-up of 24 months. Secondary outcomes included functional tests and clinical laxity measurements at 6, 12, and 24 months postoperatively. Concurrent intra-articular pathology at the time of surgery and postoperative complications were also recorded. Statistical analyses included the dependent t test and the Wilcoxon signed rank test. Results: A total of 210 rACLR patients were successfully matched to a corresponding cohort of 210 ACLR patients. There were no statistically significant differences in ACL Quality of Life (ACL-QOL) or functional testing results between the groups; however, scores in both groups showed a steady and statistically significant improvement over time. A statistically significant difference was noted with respect to the Lachman test findings, favoring the rACLR cohort (Z = -2.79, P = .005); no between-group difference was seen for the pivot-shift test (Z = -0.36, P = .72). The rACLR group had a significantly lower rate of concurrent meniscal and chondral injury. There was no difference in complications between the groups (Z = -0.49, P = .63). Conclusions: There was no difference in patient-reported or functional testing outcomes in patients undergoing remnant-sparing compared with anatomic single-bundle ACLR. There was, however, a significantly lower rate of positive Lachman test findings after rACLR. Furthermore, the rate of concurrent meniscal and chondral pathology was lower in the rACLR group. Level of Evidence: Level III, retrospective cohort study.

Arthroscopy Association of Canada Position Statement on Opioid Prescription After Arthroscopic Surgery.

Background: Despite the ongoing opioid epidemic, most patients are still prescribed a significant number of opioid medications for pain management after arthroscopic surgery. There is a need for consensus among orthopaedic surgeons and solutions to aid providers in analgesic strategies that reduce the use of opioid pain medications. Purpose: This position statement was developed with a comprehensive systematic review and meta-analysis of exclusively randomized controlled trials (RCTs) to synthesize the best available evidence for managing acute postoperative pain after arthroscopic surgery. Study Design: Position statement. Methods: The Embase, MEDLINE, PubMed, Scopus, and Web of Science databases were searched from inception until August 10, 2022. Keywords included arthroscopy, opioids, analgesia, and pain, and associated variations. We included exclusively RCTs on adult patients to gather the best available evidence for managing acute postoperative pain after arthroscopic surgery. Patient characteristics, pain, and opioid data were extracted, data were analyzed, and trial bias was evaluated. Results: A total of 21 RCTs were identified related to the prescription of opioid-sparing pain medication after arthroscopic surgery. The following recommendations regarding noninvasive, postoperative pain management strategies were made: (1) multimodal oral nonopioid analgesic regimens-including at least 1 of acetaminophen-a nonsteroidal anti-inflammatory drug-can significantly reduce opioid consumption with no change in pain scores; (2) cryotherapy is likely to help with pain management, although the evidence on the optimal method of application (continuous-flow vs ice pack application) is unclear; (3) and (4) limited RCT evidence supports the efficacy of transcutaneous electrical nerve stimulation and relaxation exercises in reducing opioid consumption after arthroscopy; and (5) limited RCT evidence exists against the efficacy of transdermal lidocaine patches in reducing opioid consumption. Conclusion: A range of nonopioid strategies exist that can reduce postarthroscopic procedural opioid consumption with equivalent vocal pain outcomes. Optimal strategies include multimodal analgesia with education and restricted/reduced opioid prescription.

Female and Younger Orthopaedic Sport Medicine Patients Are More Negatively Affected by COVID-19-Related Health Care Closures.

PURPOSE: To determine whether sex or age influence whether coronavirus disease 2019 (COVID-19) health care closures affect the health, recovery, and access to resources of preoperative and postoperative orthopaedic sports medicine patients. METHODS: Electronic questionnaires assessing physical and emotional health, the value of virtual care, and access to resources were distributed to patients with postponed (PP) orthopaedic restorative surgeries and those within 3 months' postoperative (PO), at the time of the COVID-19 health care closures. The EQ-5D-3L was included as a standardized measure of general health. Chi-square tests compared responses between sexes and age groups. Unpaired t-tests compared the EQ visual analog scale (VAS) by sex, and a one-way analysis of variance (ANOVA) compared the EQ VAS by age. RESULTS: Females in the PO group were more likely to report that their recovery was delayed (49.5% vs 36%) and that closures had negatively affected their recovery (P = .013). Females in the PP group reported more symptoms of pain/discomfort on the EQ-5D-3L (P = .023). In the PP group, patients aged 25 to 44 years were most likely to identify pain as a concern (P = .54). In the PO group, patients younger than 45 years reported a significantly lower mean EQ VAS health state (P = .017). For the final analysis, there were 115 subjects in the PP group and 198 in the PO group. CONCLUSION: This study demonstrated significant sex- and age-specific differences in health and recovery among orthopaedic sports medicine patients as a result of the COVID-19 health care closures. Females reported significantly more pain, anxiety, and delay in their rehabilitation, while younger patients reported greater negative impacts and worse overall health state.

Arthroscopy Association of Canada Position Statement on Exercise for Knee Osteoarthritis: A Systematic Review of Guidelines.

BACKGROUND: Exercise is widely regarded to improve pain and function in patients with knee osteoarthritis (OA) through building supportive muscle mass, facilitating weight loss, and through the other beneficial effects associated with it. PURPOSE: To explore literature that presents clinical guidelines for the use of exercise in the treatment of knee OA to inform an evidence-based position statement for the Arthroscopy Association of Canada. STUDY DESIGN: Position statement. METHODS: PubMed, MEDLINE, Embase, and Cochrane databases were searched for guidelines commenting on the role of exercise for knee OA. The search was limited to guidelines published in the last 10 years. Articles were screened for relevance, focusing on recently published research with clinical guidelines. Inclusion criteria involved all articles providing clinical guidelines for exercise and knee OA. RESULTS: Eight guidelines were identified. All eight recommended exercise as an important component of treatment for knee OA, with 6/8 strongly recommending it. CONCLUSION: Exercise is an effective and important component of the non-pharmacological management of knee OA. The Arthroscopy Association of Canada strongly recommends the use of exercise in the management of knee OA.

Human serum mast cell tryptase levels in elbow fractures or dislocations and its association with injury severity.

Mast cells contain an abundance of tryptase, and preclinical models have shown elevated serum mast cell tryptase (SMCT) in the setting of posttraumatic joint contractures. Therefore, SMCT emerged as a potential biomarker to help recognize patients with more severe injuries and a higher likelihood of developing contractures. The objective of this study is to assess SMCT levels in participants with varying severity of elbow fractures and/or dislocations. A prospective cohort including 13 participants with more severe injuries that required an operation and 28 participants with less severe injuries managed nonoperatively were evaluated. A control group of eight individuals without elbow injuries was also evaluated. The SMCT levels were measured using an enzyme-linked immunosorbent assay kit specific for human mast cell tryptase. A one-way analysis of variance and Tukey's Honest Significance test was used to assess for statistical significance among and between the three groups. The average time from injury to the collection of the blood samples was 4 ± 2 days. Highly significant differences were identified between the operative, nonoperative, and control groups (P = .0005). In the operative group, SMCT levels were significantly higher than the nonoperative group (P = .0005) and the control group (P = .009), suggesting a correlation between SMCT levels and injury severity. There was no statistically significant difference in SMCT levels between the nonoperative and control groups. The SMCT levels were elevated in participants with acute elbow injuries requiring operative intervention, suggesting that SMCT levels were higher in injuries regarded as more severe.

Can glenoid wear be accurately assessed using x-ray imaging? Evaluating agreement of x-ray and magnetic resonance imaging (MRI) Walch classification.

BACKGROUND: The Walch classification is the most recognized means of assessing glenoid wear in preoperative planning for shoulder arthroplasty. This classification relies on advanced imaging, which is more expensive and less practical than plain radiographs. The purpose of this study was to determine whether the Walch classification could be accurately applied to x-ray images compared with magnetic resonance imaging (MRI) as the gold standard. We hypothesized that x-ray images cannot adequately replace advanced imaging in the evaluation of glenoid wear. METHODS: Preoperative axillary x-ray images and MRI scans of 50 patients assessed for shoulder arthroplasty were independently reviewed by 5 raters. Glenoid wear was individually classified according to the Walch classification using each imaging modality. The raters then collectively reviewed the MRI scans and assigned a consensus classification to serve as the gold standard. The κ coefficient was used to determine interobserver agreement for x-ray images and independent MRI reads, as well as the agreement between x-ray images and consensus MRI. RESULTS: The inter-rater agreement for x-ray images and MRIs was "moderate" (κ = 0.42 and κ = 0.47, respectively) for the 5-category Walch classification (A1, A2, B1, B2, C) and "moderate" (κ = 0.54 and κ = 0.59, respectively) for the 3-category Walch classification (A, B, C). The agreement between x-ray images and consensus MRI was much lower: "fair-to-moderate" (κ = 0.21-0.51) for the 5-category and "moderate" (κ = 0.36-0.60) for the 3-category Walch classification. DISCUSSION: The inter-rater agreement between x-ray images and consensus MRI is "fair-to-moderate." This is lower than the previously reported reliability of the Walch classification using computed tomography scans. Accordingly, x-ray images are inferior to advanced imaging when assessing glenoid wear.

Serum Mast Cell Tryptase as a Marker of Posttraumatic Joint Contracture in a Rabbit Model.

OBJECTIVES: Mast cells have been identified as key mediators of posttraumatic joint contracture, and stabilizing medications (ketotifen) have been shown to decrease contracture severity. Serum mast cell tryptase (SMCT) levels are used clinically to monitor mast cell-mediated conditions. The goals of this study were to determine if SMCT levels are elevated in the setting of joint contracture, if they can be decreased in association with ketotifen therapy, and if they correlate with contracture severity. METHODS: This study used a previously developed rabbit model in which 39 animals were divided into 4 groups: operatively created joint contracture (ORC, n = 13), operatively created contracture treated with ketotifen at 2 doses (KF0.5, n = 9; KF1.0, n = 9), and healthy rabbits (NC, n = 8). Range of motion measures were performed at 8 weeks after the surgery. Serum samples were collected on postoperative days 1, 3, 5, 7, 21, 35, and 49. SMCT levels were measured using a rabbit-specific enzyme-linked immunosorbent assay. RESULTS: Levels of SMCT were highest in the operatively created joint contracture group and were significantly greater compared with both ketotifen groups (P < 0.001). Levels were highest at postoperative day 1 with a trend to decrease over time. A positive correlation between SMCT levels and contracture severity was observed in all operative groups (P < 0.05). CONCLUSIONS: Levels of SMCT are elevated in the setting of joint contracture, decreased in association with ketotifen therapy, and positively correlated with contracture severity. This is the first study to establish a relationship between SMCT and joint injury. Measurement of SMCT may be valuable in identifying those at risk of posttraumatic joint contracture.

The Use of Biologic Agents in Athletes with Knee Injuries.

Biologic agents are gaining popularity in the management of bony and soft tissue conditions about the knee. They are becoming the mainstay of nonoperative therapy in the high-demand athletic population. The most well-studied agents include platelet-rich plasma (PRP) and stem cells-both of which have shown promise in the treatment of various conditions. Animal and clinical studies have demonstrated improved outcomes following PRP treatment in early osteoarthritis of the knee, as well as in chronic patellar tendinopathy. Early clinical evidence also lends support for PRP in the augmentation of anterior cruciate ligament (ACL) reconstruction. Research investigating the role of biologic agents in collateral ligament and meniscal injuries is ongoing. Studies assessing the utility of stem cells have shown encouraging results in the setting of osteoarthritis. Unfortunately, strict regulations by the FDA continue to restrict their application in clinical practice. A major limitation in the interpretation of current data is the significant variability in the harvesting and preparation of both PRP and stem cells. As the volume and quality of evidence continue to grow, biologic agents are poised to become an integral component of comprehensive patient care throughout all orthopedic specialties.

The use of magnetic resonance imaging in acute knee injuries can be reduced by non-physician expert clinics.

INTRODUCTION: The routine use of magnetic resonance imaging (MRI) for the assessment of acute knee injuries is controversial. The goal of this study is to present an audit of patients seen in a dedicated Acute Knee Injury Clinic (AKIC) to determine the frequency and appropriateness of MRI utilization. METHODS: A retrospective review identified all patients who had an MRI and a randomly selected control group without MRI. The MRI was classified based on whether it was ordered by the AKIC team or by an external clinician. The consensus-based 'Indications for Urgent MRI in Acute Soft Tissue Knee Problems' were applied to both groups. An MRI was considered appropriate if any of the indications were met. RESULTS: The overall MRI utilization rate was 23% (142/611). Of the MRIs performed, 32% (46/142) met the indications. About 94% (33/35) of the MRIs ordered by the AKIC experts met the indications, compared to only 12% (13/107) of those ordered externally. No patients in the control group met the indications. Diagnoses were similar between groups. DISCUSSION: These results suggest that application of guidelines by experts in knee evaluation can significantly reduce expensive MRI utilization in patients with acute knee injuries without negatively impacting the appropriate diagnosis and disposition.

Technique of Reverse Smith Petersen Osteotomy (RSPO) in a patient with fixed lumbar hyperlordosis and negative sagittal imbalance.

STUDY DESIGN: Case report. OBJECTIVE: To determine the viability and safety of Reverse Smith Petersen Osteotomy (RSPO) to re-established sagittal balance in patients with fixed lumbar hyperlordosis. SUMMARY AND BACKGROUND DATA: Lumbar hyperlordosis is seen as a compensatory mechanism in thoracic Scheuermann disease and in sagittal decompensation in severe neuromuscular scoliosis. Hyperlordosis may also be seen after overcorrection with spinal osteotomies, but rarely causes clinically significant negative sagittal imbalance because of the thoracic compensation. We describe a case using a kyphosing osteotomy to treat hyperlordosis in a patient that was treated with a pedicle subtraction osteotomy for post-Harrington kyphosis. METHODS: The radiographs and clinical chart were reviewed of a patient treated with a RSPO at L2-L3 to correct the negative sagittal imbalance created by a previous extension of her fusion to the sacrum with a pedicle subtraction osteotomy. RESULTS: A reduction in the lumbar lordosis by 20 degrees at L2-L3 and restoration of the global sagittal balance was achieved with the RSPO. CONCLUSION: RSPO is a viable surgical technique that can be used to re-establish sagittal balance in patients with fixed lumbar hyperlordosis. Appreciation of a patient's balanced sagittal alignment and available compensatory mechanisms can help ensure appropriate osteotomies are performed.

A technique of anterior screw removal through a posterior costotransversectomy approach for posterior-based osteotomies.

STUDY DESIGN: Case report. OBJECTIVE: To describe a novel technique to remove anterior instrumentation from a posterior approach while performing posterior-based osteotomies for spinal deformities. SUMMARY OF BACKGROUND DATA: Posterior-based osteotomies such as pedicle subtraction osteotomies (PSOs) and vertebral column resections are performed to restore sagittal alignment. The removal of previously placed anterior implants at the desired osteotomy level can often be challenging. We propose a technique for the removal of anterior instrumentation through a posterior approach to facilitate osteotomy closure and deformity correction, while avoiding the need for an anterior incision. METHODS: A 34-year-old woman presented with a residual deformity after several anterior and posterior procedures. The residual coronal Cobb angle measured 60 degrees between T7 and L2, with a 46 degrees thoracolumbar kyphosis between T10 and L2. The screw head at the desired osteotomy level was in close proximity to the liver after the previous right-sided thoracoabdominal approach. Therefore, the T11 anterior screw was accessed through a posterior costotransversectomy approach and disconnected from the rod proximally and distally with a high-speed side-cutting burr. A portion of the right lateral vertebral body of T11 was removed to expose the neck of the screw, which was separated from the shaft with the same burr. A PSO was performed at T11 and the remaining screw shank was removed with the posterior-based osteotomy. RESULTS: No major complications were encountered during the procedure. The anterior screw at T11 was removed from posteriorly, and the PSO was completed successfully. Postoperative recovery was without incident, and the patient was very satisfied with her results. CONCLUSION: This technique describes a novel, safe, and effective method to deal with anterior instrumentation from the posterior approach while performing posterior-based osteotomies for rigid spinal deformities.

Ruggedness in the folding landscape of protein L.

By exploring the folding pathways of the B1 domain of protein L with a series of equilibrium and rapid kinetic experiments, we have found its unfolded state to be more complex than suggested by two-state folding models. Using an ultrarapid mixer to initiate protein folding within approximately 2-4 microseconds, we observe folding kinetics by intrinsic tryptophan fluorescence and fluorescence resonance energy transfer. We detect at least two processes faster than 100 mus that would be hidden within the burst phase of a stopped-flow instrument measuring tryptophan fluorescence. Previously reported measurements of slow intramolecular diffusion are commensurate with the slower of the two observed fast phases. These results suggest that a multidimensional energy landscape is necessary to describe the folding of protein L, and that the dynamics of the unfolded state is dominated by multiple small energy barriers.

Dynamic similarity of the unfolded states of proteins L and G.

The formation of specific intramolecular contacts has been studied under a range of denaturing conditions in single domains of the immunoglobulin-binding proteins L and G. Although they share no significant sequence similarity and have dissimilar folding pathways, the two domains have a similar native fold. Our measurements show that the rates of forming corresponding contacts in the unfolded states of both proteins are remarkably similar and even exhibit similar dependence on denaturant concentration. The unfolded proteins were modeled using Szabo, Schulten, and Schulten (SSS) theory as wormlike chains with excluded volume; when combined with our experimental data, the SSS analysis suggests that the unfolded state becomes uniformly more compact and less diffusive (i.e., rearranges more slowly) with decreasing denaturant concentrations.