Editorial Commentary: Multimodal, Opioid-Free Pain Management After Rotator Cuff Repair May Be Safe and Effective, and Decreases the Risk of Drug Abuse.

In 2020, approximately 94,000 people died in the United States due to drug overdose, a grim 78% increase since release of the American Academy of Orthopaedic Surgeons (AAOS) information statement on opioid abuse nearly 5 years ago. Annual opioid-related mortality rates now far surpass those stemming from either car crashes or gun violence. Multiple risk factors exist for opioid misuse and abuse, including a major risk factor under the orthopaedic surgeon's control-exposure to opioid medication. Prescription protocols that decrease a patient's access to narcotic medication could lead to a decrease in overall opioid abuse, while also avoiding second-order effects, such as drug diversion. Multimodal, nonopioid pain protocols often employ peripheral nerve blocks, acetaminophen, nonsteroidal anti-inflammatory medication (NSAIDs), gabapentinoids, and antispasmodic muscle relaxants, and this has yielded promising results after arthroscopic rotator cuff surgery. As good stewards of the musculoskeletal community, we should proactively employ evidence-based practices for establishing realistic postoperative patient expectations, common analgesic care pathways, and standardized pill counts stratified by procedure type.

Editorial Commentary: Repairing Retracted Rotator Cuff Tears: Histologically Different, but Success Still Achievable With "Failure in Continuity".

Failure after rotator cuff repair continues to occur despite advances in our understanding of the native tendon enthesis. Recurrent postoperative tendon defects are common, and the impact of nonhealing on postoperative outcomes remains controversial. Rotator cuff tears (RCT) of all patterns commonly present with some degree of retraction, and it is, therefore, critical to understand and examine the biology and biomechanics of the retracted RCT to address why a repaired tendon may fail. An article in this issue reports on retracted tears forming more disorganized fibrous tissue with similar biomechanical properties compared to nonretracted tear tissue. It provides insight into what lies "beneath the surface" after retracted rotator cuff repair, but it is unclear whether the fibrous tissue formed after their acute partial tendon excision adequately reflects the tissue found in more chronic, retracted human rotator cuff tears, particularly with varying degrees of retraction. Facilitating a more favorable "scar-forming" environment and optimizing this postoperative fibrous tissue may be crucial to improving rotator cuff repairs in the future.

Current Concepts in the Management of Dupuytren Disease of the Hand.

Dupuytren disease is a fibroproliferative disorder of the palmar fascia of the hand. Little agreement and remarkable variability exists in treatment algorithms between surgeons. Because the cellular and molecular etiology of Dupuytren has been elucidated, ongoing efforts have been made to identify potential chemotherapeutic targets that could modulate the phenotypic expression of the disease. Although these efforts may dramatically alter the approach to treating this disease in the future, these approaches are largely experimental at this point. Over the past decade, the mainstay nonsurgical options have continued to be percutaneous needle aponeurotomy and collagenase Clostridium hystoliticum, and the most common surgical option is limited fasciectomy.

Transcriptional profiling of synovium in a porcine model of early post-traumatic osteoarthritis.

To determine the transcriptional profile of synovium during the molecular phase of post-traumatic osteoarthritis, anterior cruciate ligament transections (ACL) were performed in 36 Yucatan minipigs. Equal numbers were randomly assigned to no further treatment, ACL reconstruction or repair. Perimeniscal synovium for histopathology and RNA-sequencing was harvested at 1 and 4 weeks post-operatively and from six healthy control animals. Microscopic synovitis scores significantly worsened at 1 (p < 0.001) and 4 weeks (p = 0.003) post-surgery relative to controls, and were driven by intimal hyperplasia and increased stromal cellularity without inflammatory infiltrates. Synovitis scores were similar between no treatment, reconstruction, and repair groups (p ≥ 0.668). Relative to no treatment at 1 week, 88 and 367 genes were differentially expressed in the reconstruction and repair groups, respectively (227 and 277 at 4 weeks). Relative to controls and with the treatment groups pooled, 1,683 transcripts were concordantly differentially expressed throughout the post-surgery time-course. Affected pathways included, proteolysis_connective tissue degradation (including upregulations of protease-encoding MMP1, MMP13, and ADAMTS4), and development_cartilage development (including upregulations of ACAN, SOX9, and RUNX2), among others. Using linear regression, significant associations of post-surgery synovial expression levels of 20 genes with the articular cartilage glycosaminoglycan loss were identified. These genes were predominantly related to embryonic skeletal system development and included RUNX2. In conclusion, this study confirmed an increased synovial expression of genes that may serve as targets to prevent cartilage degradation, including MMP1, MMP13, and ADAMTS4, in knees with microscopic synovitis and cartilage proteoglycan loss. Attractive novel targets include regulators of embryonic developmental processes in synovium. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res.

Preoperative KOOS and SF-36 Scores Are Associated With the Development of Symptomatic Knee Osteoarthritis at 7 Years After Anterior Cruciate Ligament Reconstruction.

BACKGROUND: Anterior cruciate ligament (ACL) tears are associated with the development of knee osteoarthritis despite ACL reconstruction surgery. However, little evidence is available to determine which patients will develop symptomatic knee osteoarthritis. PURPOSE: To determine if preoperative outcome measures-KOOS (Knee injury and Osteoarthritis Outcome Score) and SF-36 (36-item Short Form Health Survey)-were associated with the development of a symptomatic knee 7 years after ACL reconstruction. A secondary goal was to examine the relationship between imaging evidence of knee osteoarthritis and development of knee pain. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: Prospectively collected data from 72 patients were reviewed with 7-year follow-up after unilateral ACL reconstruction. Patients were divided into symptomatic and asymptomatic groups based on the previously defined KOOS pain ≤72. Demographic variables and preoperative KOOS and SF-36 scores were compared between groups. Radiographic and magnetic resonance imaging data were used to evaluate differences in joint space width, Osteoarthritis Research Society International radiographic score, and the Whole-Organ Magnetic Resonance Imaging Score between groups. Univariate and multivariate analyses were performed to identify potential predictors of pain at 7-year follow-up. Wilcoxon sum rank and t tests were used to compare imaging findings between the symptomatic and asymptomatic patients at 7 years. RESULTS: According to KOOS pain, 7 of the 72 patients available at 7-year follow-up formed the symptomatic group. No differences were found between groups in regard to demographic variables or intraoperative findings. In multivariate analysis, lower preoperative scores for KOOS sports/recreation ( P = .005) and SF-36 mental health ( P = .025) were associated with a painful knee at 7 years, with increased odds of 82% and 68% per 10-unit decrease, respectively. The Whole-Organ Magnetic Resonance Imaging Score at 7 years showed evidence of osteoarthritic changes in the symptomatic group as compared with the asymptomatic group ( P = .047). However, there were no significant differences in the Osteoarthritis Research Society International radiographic score ( P = .051) or joint space width ( P = .488) between groups. CONCLUSION: Lower preoperative KOOS and SF-36 scores were associated with those patients who developed symptomatic knee osteoarthritis 7 years after ACL reconstruction.

Transcriptional profiling of articular cartilage in a porcine model of early post-traumatic osteoarthritis.

To identify the molecular pathophysiology present in early post-traumatic osteoarthritis (PTOA), the transcriptional profile of articular cartilage and its response to surgical PTOA induction were determined. Thirty six Yucatan minipigs underwent anterior cruciate ligament (ACL) transection and were randomly assigned in equal numbers to no further treatment, reconstruction or ligament repair. Cartilage was harvested at 1 and 4 weeks post-operatively and histology and RNA-sequencing were performed and compared to controls. Microscopic cartilage scores significantly worsened at 1 (p = 0.028) and 4 weeks (p = 0.001) post-surgery relative to controls, but did not differ between untreated, reconstruction or repair groups. Gene expression after ACL reconstruction and ACL transection were similar, with only 0.03% (including SERPINB7 and CR2) and 0.2% of transcripts (including INHBA) differentially expressed at 1 and 4 weeks respectively. COL2A1, COMP, SPARC, CHAD, and EF1ALPHA were the most highly expressed non ribosomal, non mitochondrial genes in the controls and remained abundant after surgery. A total of 1,275 genes were differentially expressed between 1 and 4 weeks post-surgery. With the treatment groups pooled, 682 genes were differentially expressed at both time-points, with the most significant changes observed in MMP1, COCH, POSTN, CYTL1, and PTGFR. This study confirmed the development of a microscopic PTOA stage after ACL surgery in the porcine model. Upregulation of multiple proteases (including MMP1 and ADAMTS4) were found; however, the level of expression remained orders of magnitude below that of extracellular matrix protein-coding genes (including COL2A1 and ACAN). In summary, genes with established roles in PTOA as well as novel targets for specific intervention were identified. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:318-329, 2018.

Comparison of 2 Radiographic Techniques for Measurement of Tibiofemoral Joint Space Width.

BACKGROUND: No consensus is available regarding the best method for measuring tibiofemoral joint space width (JSW) on radiographs to quantify joint changes after injury. Studies that track articular cartilage thickness after injury frequently use patients' uninjured contralateral knees as controls, although the literature supporting this comparison is limited. PURPOSE: (1) To compare JSW measurements using 2 established measurement techniques in healthy control participants and (2) to determine whether the mean JSW of the uninjured contralateral knee in a cohort with anterior cruciate ligament (ACL) reconstruction is different from that obtained from a true control population. STUDY DESIGN: Cohort study (diagnosis); Level of evidence, 2. METHODS: Medial and lateral JSWs were measured on standardized, bilateral, semiflexed metatarsophalangeal positioning, posteroanterior radiographs of 60 healthy individuals (26 females; mean ± SD age, 25 ± 6.2 years; no history of knee injury) via 2 published techniques: a computerized surface-delineation method (surface-fit method) and a manual digitization method (midpoint method). Bland-Altman method was used to examine the agreement between JSW measurements obtained with the 2 methods and to examine the agreement between measurements obtained on left and right knees within a participant for each measurement method. Within- and between-participant variance components and intraclass correlation coefficients (ICCs) were computed for JSW measurements corresponding to each method. Two-sample t tests were used to compare the surface-fit method measurements of mean JSW of the true control group (n = 60) with the previously published mean JSW measurements from the Multicenter Orthopaedics Outcomes Network (MOON) nested cohort of 262 contralateral uninjured knees 2 to 3 years after ACL reconstruction. RESULTS: For JSW in the medial compartment, the surface-fit method had lower within-participant interknee variability (σ2within, 0.064; 95% CI, 0.04-0.09) compared with the midpoint method (σ2within, 0.28; 95% CI, 0.20-0.43) and a higher ICC (0.93 vs 0.65; P < .001). Lateral JSW values were similar for the surface-fit method (σ2within, 0.27; 95% CI, 0.18-0.43) and the midpoint method (σ2within, 0.20; 95% CI, 0.14-0.31), with ICCs of 0.75 and 0.77, respectively (P = .80). With the surface-fit method, mean JSW measurements of the medial and lateral compartments of a control population were not significantly different from the contralateral uninjured knees of patients after ACL reconstruction. CONCLUSION: For measuring medial JSW, the surface-fit method was less variable across knees within a participant than the midpoint method, as evidenced by larger ICCs and lower interknee variability. For measuring lateral JSW, the 2 methods were similar. The JSW measurements of uninjured contralateral knees of patients with ACL reconstruction at 2 to 3 years postsurgery were not significantly different from those of a cohort of healthy control participants. Future work should be performed to demonstrate the validity of these methods for documenting change over time in the ACL-reconstructed knee.

Effect of Matching or Overconstraining Knee Laxity During Anterior Cruciate Ligament Reconstruction on Knee Osteoarthritis and Clinical Outcomes: A Randomized Controlled Trial With 84-Month Follow-up.

BACKGROUND: The "initial graft tension" applied at the time of graft fixation during anterior cruciate ligament (ACL) reconstruction surgery modulates joint contact mechanics, which in turn may promote posttraumatic osteoarthritis (OA). PURPOSE/HYPOTHESES: The study objectives were to compare clinical, functional, patient-reported, and OA imaging outcomes between 2 different initial laxity-based graft tension cohorts and a matched uninjured control group as well as to evaluate the effects of laxity-based graft tension on OA development at 84-month follow-up. The 2 laxity-based tension protocols were (1) to restore normal anteroposterior (AP) laxity at the time of surgery relative to the contralateral uninjured knee (low-tension group) or (2) to overconstrain AP laxity by 2 mm relative to the contralateral uninjured knee (high-tension group). The hypotheses were that (1) the high-tension group would have improved outcomes and decreased OA compared with the low-tension group after 84 months, and (2) the outcomes for the high-tension group would be equivalent to those for an age-, sex-, race-, and activity-matched group of control participants with uninjured knees. STUDY DESIGN: Randomized controlled trial; Level of evidence, 1. METHODS: Patients had their ACLs reconstructed with either a bone-patellar tendon-bone or 4-stranded hamstring autograft, and outcomes were compared with a matched control group. Outcomes were evaluated preoperatively and at 60 and 84 months postoperatively and included clinical (KT-1000 arthrometer AP laxity measurement and International Knee Documentation Committee [IKDC] examination score), functional (1-legged hop for distance and knee extensor torque), patient-reported (Knee injury and Osteoarthritis Outcome Score [KOOS], Short Form-36 [SF-36], and patient satisfaction survey), and OA imaging (measurement of joint space width [JSW], Osteoarthritis Research Society International [OARSI] radiographic score, and Whole-Organ Magnetic Resonance Imaging Score [WORMS]) components. Repeated-measures analyses of variance were used to evaluate differences in outcomes between the treatment groups and the control group. RESULTS: There were significant differences between the 2 tension groups in 1 of 5 KOOS subscales (sports and recreation; P = .04) and 2 of 8 SF-36 subscales (vitality, mental health; P < .04) at 84 and 60 months, respectively. Both tension groups scored significantly worse than the control group in the IKDC examination (P < .001), 1-legged hop (P ≤ .017), KOOS quality of life and symptoms subscales (P < .03), and OARSI radiographic score (P ≤ .02) at 84 months. The low-tension group performed significantly worse than the control group on the KOOS pain subscale (P = .03), SF-36 general health and social functioning (P < .04), OARSI radiographic score (P < .001), and WORMS (P = .001), while the high-tension group had statistically different results than the control group in AP knee laxity (P < .001), radiographic JSW (P = .003), and OARSI radiographic score (P = .02) as well as significantly more subsequent knee injuries (P = .02) at 84 months. CONCLUSION: The results do not support the hypotheses that the high-tension group would have improved outcomes when compared with the low-tension group after 84 months of healing or that the outcomes for the high-tension group would be equivalent to those for the matched control group. While there were minor differences in patient-reported outcomes between the 2 laxity-based tension groups, all other outcomes were similar. REGISTRATION: NCT00434837.

Extracellular matrix-blood composite injection reduces post-traumatic osteoarthritis after anterior cruciate ligament injury in the rat.

The objective of this study was to determine if an injection of a novel extracellular matrix scaffold and blood composite (EMBC) after anterior cruciate ligament (ACL) injury would have a mitigating effect on post-traumatic osteoarthritis (PTOA) development in rat knees. Lewis rats underwent unilateral ACL transection and were divided into three groups as follows: (1) no further treatment (ACLT; n = 10); (2) an intra-articular injection of EMBC on day 0 (INJ0; n = 11); and (3) an intra-articular injection of EMBC on day 14 (INJ14; n = 11). Ten additional animals received capsulotomy only (n = 10, SHAM group). The OARSI histology scoring of the tibial cartilage and micro-CT of the tibial epiphysis were performed after 35 days. The ratio of intact/treated hind limb forces during gait was determined using a variable resistor walkway. The OARSI cartilage degradation sum score and total degeneration width were significantly greater in the ACLT group when compared to the INJ0 (p = 0.031, and p = 0.005) and INJ14 (p = 0.022 and p = 0.04) group. Weight bearing on the operated limb only decreased significantly in the ACLT group (p = 0.048). In the rat ACL transection model, early or delayed injection of EMBC ameliorated the significant decrease in weight bearing and cartilage degradation seen in knees subjected to ACL transection without injection. The results indicate that the injection of EMBC may slow the process of PTOA following ACL injury and may provide a promising treatment for PTOA. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:995-1003, 2016.

MRI volume and signal intensity of ACL graft predict clinical, functional, and patient-oriented outcome measures after ACL reconstruction.

BACKGROUND: Clinical, functional, and patient-oriented outcomes are commonly used to evaluate the efficacy of treatments after anterior cruciate ligament (ACL) injury; however, these evaluation techniques do not directly measure the biomechanical changes that occur with healing. PURPOSE: To determine if the magnetic resonance (MR) image-derived parameters of graft volume and signal intensity (SI), which have been used to predict the biomechanical (ie, structural) properties of the graft in animal models, correlate with commonly used clinical (anteroposterior [AP] knee laxity), functional (1-legged hop), and patient-oriented outcome measures (Knee Injury and Osteoarthritis Outcome Score [KOOS]) in patients 3 and 5 years after ACL reconstruction. STUDY DESIGN: Cohort study (diagnosis); Level of evidence, 3. METHODS: Based on a subset of participants enrolled in an ongoing ACL reconstruction clinical trial, AP knee laxity, 1-legged hop test, and KOOS were assessed at 3- and 5-year follow-up. Three-dimensional, T1-weighted MR images were collected at each visit. Both the volume and median SI of the healing graft were determined and used as predictors in a multiple regression linear model to predict the traditional outcome measures. RESULTS: Graft volume combined with median SI in a multiple linear regression model predicted 1-legged hop test at both the 3- and 5-year follow-up visits (R(2) = 0.40, P = .008 and R(2) = 0.62, P = .003, respectively). Similar results were found at the 5-year follow-up for the KOOS quality of life (R(2) = 0.49, P = .012), sport/function (R(2) = 0.37, P = .048), pain (R(2) = 0.46, P = .017), and symptoms (R(2) = 0.45, P = .021) subscores, although these variables were not significant at 3 years. The multiple linear regression model for AP knee laxity at 5-year follow-up approached significance (R(2) = 0.36, P = .088). CONCLUSION: The MR parameters (volume and median SI) used to predict ex vivo biomechanical properties of the graft in an animal model have the ability to predict clinical or in vivo outcome measures in patients at 3- and 5-year follow-up. CLINICAL RELEVANCE: Results from this study may enhance clinical evaluation of graft health by relating the MR parameters of volume and median SI to traditional outcome measures and could potentially aid researchers in determining the appropriate timing for athletes to return to sport.

Pendulum mass affects the measurement of articular friction coefficient.

Friction measurements of articular cartilage are important to determine the relative tribologic contributions made by synovial fluid or cartilage, and to assess the efficacy of therapies for preventing the development of post-traumatic osteoarthritis. Stanton's equation is the most frequently used formula for estimating the whole joint friction coefficient (µ) of an articular pendulum, and assumes pendulum energy loss through a mass-independent mechanism. This study examines if articular pendulum energy loss is indeed mass independent, and compares Stanton's model to an alternative model, which incorporates viscous damping, for calculating µ. Ten loads (25-100% body weight) were applied in a random order to an articular pendulum using the knees of adult male Hartley guinea pigs (n=4) as the fulcrum. Motion of the decaying pendulum was recorded and µ was estimated using two models: Stanton's equation, and an exponential decay function incorporating a viscous damping coefficient. µ estimates decreased as mass increased for both models. Exponential decay model fit error values were 82% less than the Stanton model. These results indicate that µ decreases with increasing mass, and that an exponential decay model provides a better fit for articular pendulum data at all mass values. In conclusion, inter-study comparisons of articular pendulum µ values should not be made without recognizing the loads used, as µ values are mass dependent.